NEWS
author wenzelm
Thu, 28 Feb 2013 16:19:08 +0100
changeset 52449 0ce544fbb509
parent 52432 71fc3776c453
child 52450 102a0a0718c5
permissions -rw-r--r--
more robust build error handling, e.g. missing outer syntax commands;
     1 Isabelle NEWS -- history user-relevant changes
     2 ==============================================
     3 
     4 New in this Isabelle version
     5 ----------------------------
     6 
     7 *** General ***
     8 
     9 * Discontinued obsolete 'uses' within theory header.  Note that
    10 commands like 'ML_file' work without separate declaration of file
    11 dependencies.  Minor INCOMPATIBILITY.
    12 
    13 * Discontinued redundant 'use' command, which was superseded by
    14 'ML_file' in Isabelle2013.  Minor INCOMPATIBILITY.
    15 
    16 
    17 *** HOL ***
    18 
    19 * Discontinued obsolete src/HOL/IsaMakefile (considered legacy since
    20 Isabelle2013).  Use "isabelle build" to operate on Isabelle sessions.
    21 
    22 * Numeric types mapped by default to target language numerals:
    23 natural (replaces former code_numeral) and integer (replaces
    24 former code_int).  Conversions are available as integer_of_natural /
    25 natural_of_integer / integer_of_nat / nat_of_integer (in HOL) and
    26 Code_Numeral.integer_of_natural / Code_Numeral.natural_of_integer (in ML).
    27 INCOMPATIBILITY.
    28 
    29 * Discontinued theories Code_Integer and Efficient_Nat by a more
    30 fine-grain stack of theories Code_Target_Int, Code_Binary_Nat,
    31 Code_Target_Nat and Code_Target_Numeral.  See the tutorial on
    32 code generation for details.  INCOMPATIBILITY.
    33 
    34 * Theory "RealVector" and "Limits": Introduce type class
    35 (lin)order_topology. Allows to generalize theorems about limits and
    36 order. Instances are reals and extended reals.
    37 
    38 * Consolidation of library theories on product orders:
    39 
    40     Product_Lattice ~> Product_Order -- pointwise order on products
    41     Product_ord ~> Product_Lexorder -- lexicographic order on products
    42 
    43 INCOMPATIBILITY.
    44 
    45 * Sledgehammer:
    46 
    47   - Renamed option:
    48       isar_shrink ~> isar_compress
    49 
    50 
    51 New in Isabelle2013 (February 2013)
    52 -----------------------------------
    53 
    54 *** General ***
    55 
    56 * Theorem status about oracles and unfinished/failed future proofs is
    57 no longer printed by default, since it is incompatible with
    58 incremental / parallel checking of the persistent document model.  ML
    59 function Thm.peek_status may be used to inspect a snapshot of the
    60 ongoing evaluation process.  Note that in batch mode --- notably
    61 isabelle build --- the system ensures that future proofs of all
    62 accessible theorems in the theory context are finished (as before).
    63 
    64 * Configuration option show_markup controls direct inlining of markup
    65 into the printed representation of formal entities --- notably type
    66 and sort constraints.  This enables Prover IDE users to retrieve that
    67 information via tooltips in the output window, for example.
    68 
    69 * Command 'ML_file' evaluates ML text from a file directly within the
    70 theory, without any predeclaration via 'uses' in the theory header.
    71 
    72 * Old command 'use' command and corresponding keyword 'uses' in the
    73 theory header are legacy features and will be discontinued soon.
    74 Tools that load their additional source files may imitate the
    75 'ML_file' implementation, such that the system can take care of
    76 dependencies properly.
    77 
    78 * Discontinued obsolete method fastsimp / tactic fast_simp_tac, which
    79 is called fastforce / fast_force_tac already since Isabelle2011-1.
    80 
    81 * Updated and extended "isar-ref" and "implementation" manual, reduced
    82 remaining material in old "ref" manual.
    83 
    84 * Improved support for auxiliary contexts that indicate block structure
    85 for specifications.  Nesting of "context fixes ... context assumes ..."
    86 and "class ... context ...".
    87 
    88 * Attribute "consumes" allows a negative value as well, which is
    89 interpreted relatively to the total number of premises of the rule in
    90 the target context.  This form of declaration is stable when exported
    91 from a nested 'context' with additional assumptions.  It is the
    92 preferred form for definitional packages, notably cases/rules produced
    93 in HOL/inductive and HOL/function.
    94 
    95 * More informative error messages for Isar proof commands involving
    96 lazy enumerations (method applications etc.).
    97 
    98 * Refined 'help' command to retrieve outer syntax commands according
    99 to name patterns (with clickable results).
   100 
   101 
   102 *** Prover IDE -- Isabelle/Scala/jEdit ***
   103 
   104 * Parallel terminal proofs ('by') are enabled by default, likewise
   105 proofs that are built into packages like 'datatype', 'function'.  This
   106 allows to "run ahead" checking the theory specifications on the
   107 surface, while the prover is still crunching on internal
   108 justifications.  Unfinished / cancelled proofs are restarted as
   109 required to complete full proof checking eventually.
   110 
   111 * Improved output panel with tooltips, hyperlinks etc. based on the
   112 same Rich_Text_Area as regular Isabelle/jEdit buffers.  Activation of
   113 tooltips leads to some window that supports the same recursively,
   114 which can lead to stacks of tooltips as the semantic document content
   115 is explored.  ESCAPE closes the whole stack, individual windows may be
   116 closed separately, or detached to become independent jEdit dockables.
   117 
   118 * Improved support for commands that produce graph output: the text
   119 message contains a clickable area to open a new instance of the graph
   120 browser on demand.
   121 
   122 * More robust incremental parsing of outer syntax (partial comments,
   123 malformed symbols).  Changing the balance of open/close quotes and
   124 comment delimiters works more conveniently with unfinished situations
   125 that frequently occur in user interaction.
   126 
   127 * More efficient painting and improved reactivity when editing large
   128 files.  More scalable management of formal document content.
   129 
   130 * Smarter handling of tracing messages: prover process pauses after
   131 certain number of messages per command transaction, with some user
   132 dialog to stop or continue.  This avoids swamping the front-end with
   133 potentially infinite message streams.
   134 
   135 * More plugin options and preferences, based on Isabelle/Scala.  The
   136 jEdit plugin option panel provides access to some Isabelle/Scala
   137 options, including tuning parameters for editor reactivity and color
   138 schemes.
   139 
   140 * Dockable window "Symbols" provides some editing support for Isabelle
   141 symbols.
   142 
   143 * Dockable window "Monitor" shows ML runtime statistics.  Note that
   144 continuous display of the chart slows down the system.
   145 
   146 * Improved editing support for control styles: subscript, superscript,
   147 bold, reset of style -- operating on single symbols or text
   148 selections.  Cf. keyboard shortcuts C+e DOWN/UP/RIGHT/LEFT.
   149 
   150 * Actions isabelle.increase-font-size and isabelle.decrease-font-size
   151 adjust the main text area font size, and its derivatives for output,
   152 tooltips etc.  Cf. keyboard shortcuts C-PLUS and C-MINUS, which often
   153 need to be adapted to local keyboard layouts.
   154 
   155 * More reactive completion popup by default: use \t (TAB) instead of
   156 \n (NEWLINE) to minimize intrusion into regular flow of editing.  See
   157 also "Plugin Options / SideKick / General / Code Completion Options".
   158 
   159 * Implicit check and build dialog of the specified logic session
   160 image.  For example, HOL, HOLCF, HOL-Nominal can be produced on
   161 demand, without bundling big platform-dependent heap images in the
   162 Isabelle distribution.
   163 
   164 * Uniform Java 7 platform on Linux, Mac OS X, Windows: recent updates
   165 from Oracle provide better multi-platform experience.  This version is
   166 now bundled exclusively with Isabelle.
   167 
   168 
   169 *** Pure ***
   170 
   171 * Code generation for Haskell: restrict unqualified imports from
   172 Haskell Prelude to a small set of fundamental operations.
   173 
   174 * Command 'export_code': relative file names are interpreted
   175 relatively to master directory of current theory rather than the
   176 rather arbitrary current working directory.  INCOMPATIBILITY.
   177 
   178 * Discontinued obsolete attribute "COMP".  Potential INCOMPATIBILITY,
   179 use regular rule composition via "OF" / "THEN", or explicit proof
   180 structure instead.  Note that Isabelle/ML provides a variety of
   181 operators like COMP, INCR_COMP, COMP_INCR, which need to be applied
   182 with some care where this is really required.
   183 
   184 * Command 'typ' supports an additional variant with explicit sort
   185 constraint, to infer and check the most general type conforming to a
   186 given sort.  Example (in HOL):
   187 
   188   typ "_ * _ * bool * unit" :: finite
   189 
   190 * Command 'locale_deps' visualizes all locales and their relations as
   191 a Hasse diagram.
   192 
   193 
   194 *** HOL ***
   195 
   196 * Sledgehammer:
   197 
   198   - Added MaSh relevance filter based on machine-learning; see the
   199     Sledgehammer manual for details.
   200   - Polished Isar proofs generated with "isar_proofs" option.
   201   - Rationalized type encodings ("type_enc" option).
   202   - Renamed "kill_provers" subcommand to "kill_all".
   203   - Renamed options:
   204       isar_proof ~> isar_proofs
   205       isar_shrink_factor ~> isar_shrink
   206       max_relevant ~> max_facts
   207       relevance_thresholds ~> fact_thresholds
   208 
   209 * Quickcheck: added an optimisation for equality premises.  It is
   210 switched on by default, and can be switched off by setting the
   211 configuration quickcheck_optimise_equality to false.
   212 
   213 * Quotient: only one quotient can be defined by quotient_type
   214 INCOMPATIBILITY.
   215 
   216 * Lifting:
   217   - generation of an abstraction function equation in lift_definition
   218   - quot_del attribute
   219   - renamed no_abs_code -> no_code (INCOMPATIBILITY.)
   220 
   221 * Simproc "finite_Collect" rewrites set comprehensions into pointfree
   222 expressions.
   223 
   224 * Preprocessing of the code generator rewrites set comprehensions into
   225 pointfree expressions.
   226 
   227 * The SMT solver Z3 has now by default a restricted set of directly
   228 supported features. For the full set of features (div/mod, nonlinear
   229 arithmetic, datatypes/records) with potential proof reconstruction
   230 failures, enable the configuration option "z3_with_extensions".  Minor
   231 INCOMPATIBILITY.
   232 
   233 * Simplified 'typedef' specifications: historical options for implicit
   234 set definition and alternative name have been discontinued.  The
   235 former behavior of "typedef (open) t = A" is now the default, but
   236 written just "typedef t = A".  INCOMPATIBILITY, need to adapt theories
   237 accordingly.
   238 
   239 * Removed constant "chars"; prefer "Enum.enum" on type "char"
   240 directly.  INCOMPATIBILITY.
   241 
   242 * Moved operation product, sublists and n_lists from theory Enum to
   243 List.  INCOMPATIBILITY.
   244 
   245 * Theorem UN_o generalized to SUP_comp.  INCOMPATIBILITY.
   246 
   247 * Class "comm_monoid_diff" formalises properties of bounded
   248 subtraction, with natural numbers and multisets as typical instances.
   249 
   250 * Added combinator "Option.these" with type "'a option set => 'a set".
   251 
   252 * Theory "Transitive_Closure": renamed lemmas
   253 
   254   reflcl_tranclp -> reflclp_tranclp
   255   rtranclp_reflcl -> rtranclp_reflclp
   256 
   257 INCOMPATIBILITY.
   258 
   259 * Theory "Rings": renamed lemmas (in class semiring)
   260 
   261   left_distrib ~> distrib_right
   262   right_distrib ~> distrib_left
   263 
   264 INCOMPATIBILITY.
   265 
   266 * Generalized the definition of limits:
   267 
   268   - Introduced the predicate filterlim (LIM x F. f x :> G) which
   269     expresses that when the input values x converge to F then the
   270     output f x converges to G.
   271 
   272   - Added filters for convergence to positive (at_top) and negative
   273     infinity (at_bot).
   274 
   275   - Moved infinity in the norm (at_infinity) from
   276     Multivariate_Analysis to Complex_Main.
   277 
   278   - Removed real_tendsto_inf, it is superseded by "LIM x F. f x :>
   279     at_top".
   280 
   281 INCOMPATIBILITY.
   282 
   283 * Theory "Library/Option_ord" provides instantiation of option type to
   284 lattice type classes.
   285 
   286 * Theory "Library/Multiset": renamed
   287 
   288     constant fold_mset ~> Multiset.fold
   289     fact fold_mset_commute ~> fold_mset_comm
   290 
   291 INCOMPATIBILITY.
   292 
   293 * Renamed theory Library/List_Prefix to Library/Sublist, with related
   294 changes as follows.
   295 
   296   - Renamed constants (and related lemmas)
   297 
   298       prefix ~> prefixeq
   299       strict_prefix ~> prefix
   300 
   301   - Replaced constant "postfix" by "suffixeq" with swapped argument
   302     order (i.e., "postfix xs ys" is now "suffixeq ys xs") and dropped
   303     old infix syntax "xs >>= ys"; use "suffixeq ys xs" instead.
   304     Renamed lemmas accordingly.
   305 
   306   - Added constant "list_hembeq" for homeomorphic embedding on
   307     lists. Added abbreviation "sublisteq" for special case
   308     "list_hembeq (op =)".
   309 
   310   - Theory Library/Sublist no longer provides "order" and "bot" type
   311     class instances for the prefix order (merely corresponding locale
   312     interpretations). The type class instances are now in theory
   313     Library/Prefix_Order.
   314 
   315   - The sublist relation of theory Library/Sublist_Order is now based
   316     on "Sublist.sublisteq".  Renamed lemmas accordingly:
   317 
   318       le_list_append_le_same_iff ~> Sublist.sublisteq_append_le_same_iff
   319       le_list_append_mono ~> Sublist.list_hembeq_append_mono
   320       le_list_below_empty ~> Sublist.list_hembeq_Nil, Sublist.list_hembeq_Nil2
   321       le_list_Cons_EX ~> Sublist.list_hembeq_ConsD
   322       le_list_drop_Cons2 ~> Sublist.sublisteq_Cons2'
   323       le_list_drop_Cons_neq ~> Sublist.sublisteq_Cons2_neq
   324       le_list_drop_Cons ~> Sublist.sublisteq_Cons'
   325       le_list_drop_many ~> Sublist.sublisteq_drop_many
   326       le_list_filter_left ~> Sublist.sublisteq_filter_left
   327       le_list_rev_drop_many ~> Sublist.sublisteq_rev_drop_many
   328       le_list_rev_take_iff ~> Sublist.sublisteq_append
   329       le_list_same_length ~> Sublist.sublisteq_same_length
   330       le_list_take_many_iff ~> Sublist.sublisteq_append'
   331       less_eq_list.drop ~> less_eq_list_drop
   332       less_eq_list.induct ~> less_eq_list_induct
   333       not_le_list_length ~> Sublist.not_sublisteq_length
   334 
   335 INCOMPATIBILITY.
   336 
   337 * New theory Library/Countable_Set.
   338 
   339 * Theory Library/Debug and Library/Parallel provide debugging and
   340 parallel execution for code generated towards Isabelle/ML.
   341 
   342 * Theory Library/FuncSet: Extended support for Pi and extensional and
   343 introduce the extensional dependent function space "PiE". Replaced
   344 extensional_funcset by an abbreviation, and renamed lemmas from
   345 extensional_funcset to PiE as follows:
   346 
   347   extensional_empty  ~>  PiE_empty
   348   extensional_funcset_empty_domain  ~>  PiE_empty_domain
   349   extensional_funcset_empty_range  ~>  PiE_empty_range
   350   extensional_funcset_arb  ~>  PiE_arb
   351   extensional_funcset_mem  ~>  PiE_mem
   352   extensional_funcset_extend_domainI  ~>  PiE_fun_upd
   353   extensional_funcset_restrict_domain  ~>  fun_upd_in_PiE
   354   extensional_funcset_extend_domain_eq  ~>  PiE_insert_eq
   355   card_extensional_funcset  ~>  card_PiE
   356   finite_extensional_funcset  ~>  finite_PiE
   357 
   358 INCOMPATIBILITY.
   359 
   360 * Theory Library/FinFun: theory of almost everywhere constant
   361 functions (supersedes the AFP entry "Code Generation for Functions as
   362 Data").
   363 
   364 * Theory Library/Phantom: generic phantom type to make a type
   365 parameter appear in a constant's type.  This alternative to adding
   366 TYPE('a) as another parameter avoids unnecessary closures in generated
   367 code.
   368 
   369 * Theory Library/RBT_Impl: efficient construction of red-black trees
   370 from sorted associative lists. Merging two trees with rbt_union may
   371 return a structurally different tree than before.  Potential
   372 INCOMPATIBILITY.
   373 
   374 * Theory Library/IArray: immutable arrays with code generation.
   375 
   376 * Theory Library/Finite_Lattice: theory of finite lattices.
   377 
   378 * HOL/Multivariate_Analysis: replaced
   379 
   380   "basis :: 'a::euclidean_space => nat => real"
   381   "\<Chi>\<Chi> :: (nat => real) => 'a::euclidean_space"
   382 
   383 on euclidean spaces by using the inner product "_ \<bullet> _" with
   384 vectors from the Basis set: "\<Chi>\<Chi> i. f i" is superseded by
   385 "SUM i : Basis. f i * r i".
   386 
   387   With this change the following constants are also changed or removed:
   388 
   389     DIM('a) :: nat  ~>  card (Basis :: 'a set)   (is an abbreviation)
   390     a $$ i  ~>  inner a i  (where i : Basis)
   391     cart_base i  removed
   392     \<pi>, \<pi>'  removed
   393 
   394   Theorems about these constants where removed.
   395 
   396   Renamed lemmas:
   397 
   398     component_le_norm  ~>  Basis_le_norm
   399     euclidean_eq  ~>  euclidean_eq_iff
   400     differential_zero_maxmin_component  ~>  differential_zero_maxmin_cart
   401     euclidean_simps  ~>  inner_simps
   402     independent_basis  ~>  independent_Basis
   403     span_basis  ~>  span_Basis
   404     in_span_basis  ~>  in_span_Basis
   405     norm_bound_component_le  ~>  norm_boound_Basis_le
   406     norm_bound_component_lt  ~>  norm_boound_Basis_lt
   407     component_le_infnorm  ~>  Basis_le_infnorm
   408 
   409 INCOMPATIBILITY.
   410 
   411 * HOL/Probability:
   412 
   413   - Added simproc "measurable" to automatically prove measurability.
   414 
   415   - Added induction rules for sigma sets with disjoint union
   416     (sigma_sets_induct_disjoint) and for Borel-measurable functions
   417     (borel_measurable_induct).
   418 
   419   - Added the Daniell-Kolmogorov theorem (the existence the limit of a
   420     projective family).
   421 
   422 * HOL/Cardinals: Theories of ordinals and cardinals (supersedes the
   423 AFP entry "Ordinals_and_Cardinals").
   424 
   425 * HOL/BNF: New (co)datatype package based on bounded natural functors
   426 with support for mixed, nested recursion and interesting non-free
   427 datatypes.
   428 
   429 * HOL/Finite_Set and Relation: added new set and relation operations
   430 expressed by Finite_Set.fold.
   431 
   432 * New theory HOL/Library/RBT_Set: implementation of sets by red-black
   433 trees for the code generator.
   434 
   435 * HOL/Library/RBT and HOL/Library/Mapping have been converted to
   436 Lifting/Transfer.
   437 possible INCOMPATIBILITY.
   438 
   439 * HOL/Set: renamed Set.project -> Set.filter
   440 INCOMPATIBILITY.
   441 
   442 
   443 *** Document preparation ***
   444 
   445 * Dropped legacy antiquotations "term_style" and "thm_style", since
   446 styles may be given as arguments to "term" and "thm" already.
   447 Discontinued legacy styles "prem1" .. "prem19".
   448 
   449 * Default LaTeX rendering for \<euro> is now based on eurosym package,
   450 instead of slightly exotic babel/greek.
   451 
   452 * Document variant NAME may use different LaTeX entry point
   453 document/root_NAME.tex if that file exists, instead of the common
   454 document/root.tex.
   455 
   456 * Simplified custom document/build script, instead of old-style
   457 document/IsaMakefile.  Minor INCOMPATIBILITY.
   458 
   459 
   460 *** ML ***
   461 
   462 * The default limit for maximum number of worker threads is now 8,
   463 instead of 4, in correspondence to capabilities of contemporary
   464 hardware and Poly/ML runtime system.
   465 
   466 * Type Seq.results and related operations support embedded error
   467 messages within lazy enumerations, and thus allow to provide
   468 informative errors in the absence of any usable results.
   469 
   470 * Renamed Position.str_of to Position.here to emphasize that this is a
   471 formal device to inline positions into message text, but not
   472 necessarily printing visible text.
   473 
   474 
   475 *** System ***
   476 
   477 * Advanced support for Isabelle sessions and build management, see
   478 "system" manual for the chapter of that name, especially the "isabelle
   479 build" tool and its examples.  The "isabelle mkroot" tool prepares
   480 session root directories for use with "isabelle build", similar to
   481 former "isabelle mkdir" for "isabelle usedir".  Note that this affects
   482 document preparation as well.  INCOMPATIBILITY, isabelle usedir /
   483 mkdir / make are rendered obsolete.
   484 
   485 * Discontinued obsolete Isabelle/build script, it is superseded by the
   486 regular isabelle build tool.  For example:
   487 
   488   isabelle build -s -b HOL
   489 
   490 * Discontinued obsolete "isabelle makeall".
   491 
   492 * Discontinued obsolete IsaMakefile and ROOT.ML files from the
   493 Isabelle distribution, except for rudimentary src/HOL/IsaMakefile that
   494 provides some traditional targets that invoke "isabelle build".  Note
   495 that this is inefficient!  Applications of Isabelle/HOL involving
   496 "isabelle make" should be upgraded to use "isabelle build" directly.
   497 
   498 * The "isabelle options" tool prints Isabelle system options, as
   499 required for "isabelle build", for example.
   500 
   501 * The "isabelle logo" tool produces EPS and PDF format simultaneously.
   502 Minor INCOMPATIBILITY in command-line options.
   503 
   504 * The "isabelle install" tool has now a simpler command-line.  Minor
   505 INCOMPATIBILITY.
   506 
   507 * The "isabelle components" tool helps to resolve add-on components
   508 that are not bundled, or referenced from a bare-bones repository
   509 version of Isabelle.
   510 
   511 * Settings variable ISABELLE_PLATFORM_FAMILY refers to the general
   512 platform family: "linux", "macos", "windows".
   513 
   514 * The ML system is configured as regular component, and no longer
   515 picked up from some surrounding directory.  Potential INCOMPATIBILITY
   516 for home-made settings.
   517 
   518 * Improved ML runtime statistics (heap, threads, future tasks etc.).
   519 
   520 * Discontinued support for Poly/ML 5.2.1, which was the last version
   521 without exception positions and advanced ML compiler/toplevel
   522 configuration.
   523 
   524 * Discontinued special treatment of Proof General -- no longer guess
   525 PROOFGENERAL_HOME based on accidental file-system layout.  Minor
   526 INCOMPATIBILITY: provide PROOFGENERAL_HOME and PROOFGENERAL_OPTIONS
   527 settings manually, or use a Proof General version that has been
   528 bundled as Isabelle component.
   529 
   530 
   531 
   532 New in Isabelle2012 (May 2012)
   533 ------------------------------
   534 
   535 *** General ***
   536 
   537 * Prover IDE (PIDE) improvements:
   538 
   539   - more robust Sledgehammer integration (as before the sledgehammer
   540     command-line needs to be typed into the source buffer)
   541   - markup for bound variables
   542   - markup for types of term variables (displayed as tooltips)
   543   - support for user-defined Isar commands within the running session
   544   - improved support for Unicode outside original 16bit range
   545     e.g. glyph for \<A> (thanks to jEdit 4.5.1)
   546 
   547 * Forward declaration of outer syntax keywords within the theory
   548 header -- minor INCOMPATIBILITY for user-defined commands.  Allow new
   549 commands to be used in the same theory where defined.
   550 
   551 * Auxiliary contexts indicate block structure for specifications with
   552 additional parameters and assumptions.  Such unnamed contexts may be
   553 nested within other targets, like 'theory', 'locale', 'class',
   554 'instantiation' etc.  Results from the local context are generalized
   555 accordingly and applied to the enclosing target context.  Example:
   556 
   557   context
   558     fixes x y z :: 'a
   559     assumes xy: "x = y" and yz: "y = z"
   560   begin
   561 
   562   lemma my_trans: "x = z" using xy yz by simp
   563 
   564   end
   565 
   566   thm my_trans
   567 
   568 The most basic application is to factor-out context elements of
   569 several fixes/assumes/shows theorem statements, e.g. see
   570 ~~/src/HOL/Isar_Examples/Group_Context.thy
   571 
   572 Any other local theory specification element works within the "context
   573 ... begin ... end" block as well.
   574 
   575 * Bundled declarations associate attributed fact expressions with a
   576 given name in the context.  These may be later included in other
   577 contexts.  This allows to manage context extensions casually, without
   578 the logical dependencies of locales and locale interpretation.  See
   579 commands 'bundle', 'include', 'including' etc. in the isar-ref manual.
   580 
   581 * Commands 'lemmas' and 'theorems' allow local variables using 'for'
   582 declaration, and results are standardized before being stored.  Thus
   583 old-style "standard" after instantiation or composition of facts
   584 becomes obsolete.  Minor INCOMPATIBILITY, due to potential change of
   585 indices of schematic variables.
   586 
   587 * Rule attributes in local theory declarations (e.g. locale or class)
   588 are now statically evaluated: the resulting theorem is stored instead
   589 of the original expression.  INCOMPATIBILITY in rare situations, where
   590 the historic accident of dynamic re-evaluation in interpretations
   591 etc. was exploited.
   592 
   593 * New tutorial "Programming and Proving in Isabelle/HOL"
   594 ("prog-prove").  It completely supersedes "A Tutorial Introduction to
   595 Structured Isar Proofs" ("isar-overview"), which has been removed.  It
   596 also supersedes "Isabelle/HOL, A Proof Assistant for Higher-Order
   597 Logic" as the recommended beginners tutorial, but does not cover all
   598 of the material of that old tutorial.
   599 
   600 * Updated and extended reference manuals: "isar-ref",
   601 "implementation", "system"; reduced remaining material in old "ref"
   602 manual.
   603 
   604 
   605 *** Pure ***
   606 
   607 * Command 'definition' no longer exports the foundational "raw_def"
   608 into the user context.  Minor INCOMPATIBILITY, may use the regular
   609 "def" result with attribute "abs_def" to imitate the old version.
   610 
   611 * Attribute "abs_def" turns an equation of the form "f x y == t" into
   612 "f == %x y. t", which ensures that "simp" or "unfold" steps always
   613 expand it.  This also works for object-logic equality.  (Formerly
   614 undocumented feature.)
   615 
   616 * Sort constraints are now propagated in simultaneous statements, just
   617 like type constraints.  INCOMPATIBILITY in rare situations, where
   618 distinct sorts used to be assigned accidentally.  For example:
   619 
   620   lemma "P (x::'a::foo)" and "Q (y::'a::bar)"  -- "now illegal"
   621 
   622   lemma "P (x::'a)" and "Q (y::'a::bar)"
   623     -- "now uniform 'a::bar instead of default sort for first occurrence (!)"
   624 
   625 * Rule composition via attribute "OF" (or ML functions OF/MRS) is more
   626 tolerant against multiple unifiers, as long as the final result is
   627 unique.  (As before, rules are composed in canonical right-to-left
   628 order to accommodate newly introduced premises.)
   629 
   630 * Renamed some inner syntax categories:
   631 
   632     num ~> num_token
   633     xnum ~> xnum_token
   634     xstr ~> str_token
   635 
   636 Minor INCOMPATIBILITY.  Note that in practice "num_const" or
   637 "num_position" etc. are mainly used instead (which also include
   638 position information via constraints).
   639 
   640 * Simplified configuration options for syntax ambiguity: see
   641 "syntax_ambiguity_warning" and "syntax_ambiguity_limit" in isar-ref
   642 manual.  Minor INCOMPATIBILITY.
   643 
   644 * Discontinued configuration option "syntax_positions": atomic terms
   645 in parse trees are always annotated by position constraints.
   646 
   647 * Old code generator for SML and its commands 'code_module',
   648 'code_library', 'consts_code', 'types_code' have been discontinued.
   649 Use commands of the generic code generator instead.  INCOMPATIBILITY.
   650 
   651 * Redundant attribute "code_inline" has been discontinued. Use
   652 "code_unfold" instead.  INCOMPATIBILITY.
   653 
   654 * Dropped attribute "code_unfold_post" in favor of the its dual
   655 "code_abbrev", which yields a common pattern in definitions like
   656 
   657   definition [code_abbrev]: "f = t"
   658 
   659 INCOMPATIBILITY.
   660 
   661 * Obsolete 'types' command has been discontinued.  Use 'type_synonym'
   662 instead.  INCOMPATIBILITY.
   663 
   664 * Discontinued old "prems" fact, which used to refer to the accidental
   665 collection of foundational premises in the context (already marked as
   666 legacy since Isabelle2011).
   667 
   668 
   669 *** HOL ***
   670 
   671 * Type 'a set is now a proper type constructor (just as before
   672 Isabelle2008).  Definitions mem_def and Collect_def have disappeared.
   673 Non-trivial INCOMPATIBILITY.  For developments keeping predicates and
   674 sets separate, it is often sufficient to rephrase some set S that has
   675 been accidentally used as predicates by "%x. x : S", and some
   676 predicate P that has been accidentally used as set by "{x. P x}".
   677 Corresponding proofs in a first step should be pruned from any
   678 tinkering with former theorems mem_def and Collect_def as far as
   679 possible.
   680 
   681 For developments which deliberately mix predicates and sets, a
   682 planning step is necessary to determine what should become a predicate
   683 and what a set.  It can be helpful to carry out that step in
   684 Isabelle2011-1 before jumping right into the current release.
   685 
   686 * Code generation by default implements sets as container type rather
   687 than predicates.  INCOMPATIBILITY.
   688 
   689 * New type synonym 'a rel = ('a * 'a) set
   690 
   691 * The representation of numerals has changed.  Datatype "num"
   692 represents strictly positive binary numerals, along with functions
   693 "numeral :: num => 'a" and "neg_numeral :: num => 'a" to represent
   694 positive and negated numeric literals, respectively.  See also
   695 definitions in ~~/src/HOL/Num.thy.  Potential INCOMPATIBILITY, some
   696 user theories may require adaptations as follows:
   697 
   698   - Theorems with number_ring or number_semiring constraints: These
   699     classes are gone; use comm_ring_1 or comm_semiring_1 instead.
   700 
   701   - Theories defining numeric types: Remove number, number_semiring,
   702     and number_ring instances. Defer all theorems about numerals until
   703     after classes one and semigroup_add have been instantiated.
   704 
   705   - Numeral-only simp rules: Replace each rule having a "number_of v"
   706     pattern with two copies, one for numeral and one for neg_numeral.
   707 
   708   - Theorems about subclasses of semiring_1 or ring_1: These classes
   709     automatically support numerals now, so more simp rules and
   710     simprocs may now apply within the proof.
   711 
   712   - Definitions and theorems using old constructors Pls/Min/Bit0/Bit1:
   713     Redefine using other integer operations.
   714 
   715 * Transfer: New package intended to generalize the existing
   716 "descending" method and related theorem attributes from the Quotient
   717 package.  (Not all functionality is implemented yet, but future
   718 development will focus on Transfer as an eventual replacement for the
   719 corresponding parts of the Quotient package.)
   720 
   721   - transfer_rule attribute: Maintains a collection of transfer rules,
   722     which relate constants at two different types. Transfer rules may
   723     relate different type instances of the same polymorphic constant,
   724     or they may relate an operation on a raw type to a corresponding
   725     operation on an abstract type (quotient or subtype). For example:
   726 
   727     ((A ===> B) ===> list_all2 A ===> list_all2 B) map map
   728     (cr_int ===> cr_int ===> cr_int) (%(x,y) (u,v). (x+u, y+v)) plus_int
   729 
   730   - transfer method: Replaces a subgoal on abstract types with an
   731     equivalent subgoal on the corresponding raw types. Constants are
   732     replaced with corresponding ones according to the transfer rules.
   733     Goals are generalized over all free variables by default; this is
   734     necessary for variables whose types change, but can be overridden
   735     for specific variables with e.g. "transfer fixing: x y z".  The
   736     variant transfer' method allows replacing a subgoal with one that
   737     is logically stronger (rather than equivalent).
   738 
   739   - relator_eq attribute: Collects identity laws for relators of
   740     various type constructors, e.g. "list_all2 (op =) = (op =)".  The
   741     transfer method uses these lemmas to infer transfer rules for
   742     non-polymorphic constants on the fly.
   743 
   744   - transfer_prover method: Assists with proving a transfer rule for a
   745     new constant, provided the constant is defined in terms of other
   746     constants that already have transfer rules. It should be applied
   747     after unfolding the constant definitions.
   748 
   749   - HOL/ex/Transfer_Int_Nat.thy: Example theory demonstrating transfer
   750     from type nat to type int.
   751 
   752 * Lifting: New package intended to generalize the quotient_definition
   753 facility of the Quotient package; designed to work with Transfer.
   754 
   755   - lift_definition command: Defines operations on an abstract type in
   756     terms of a corresponding operation on a representation
   757     type.  Example syntax:
   758 
   759     lift_definition dlist_insert :: "'a => 'a dlist => 'a dlist"
   760       is List.insert
   761 
   762     Users must discharge a respectfulness proof obligation when each
   763     constant is defined. (For a type copy, i.e. a typedef with UNIV,
   764     the proof is discharged automatically.) The obligation is
   765     presented in a user-friendly, readable form; a respectfulness
   766     theorem in the standard format and a transfer rule are generated
   767     by the package.
   768 
   769   - Integration with code_abstype: For typedefs (e.g. subtypes
   770     corresponding to a datatype invariant, such as dlist),
   771     lift_definition generates a code certificate theorem and sets up
   772     code generation for each constant.
   773 
   774   - setup_lifting command: Sets up the Lifting package to work with a
   775     user-defined type. The user must provide either a quotient theorem
   776     or a type_definition theorem.  The package configures transfer
   777     rules for equality and quantifiers on the type, and sets up the
   778     lift_definition command to work with the type.
   779 
   780   - Usage examples: See Quotient_Examples/Lift_DList.thy,
   781     Quotient_Examples/Lift_RBT.thy, Quotient_Examples/Lift_FSet.thy,
   782     Word/Word.thy and Library/Float.thy.
   783 
   784 * Quotient package:
   785 
   786   - The 'quotient_type' command now supports a 'morphisms' option with
   787     rep and abs functions, similar to typedef.
   788 
   789   - 'quotient_type' sets up new types to work with the Lifting and
   790     Transfer packages, as with 'setup_lifting'.
   791 
   792   - The 'quotient_definition' command now requires the user to prove a
   793     respectfulness property at the point where the constant is
   794     defined, similar to lift_definition; INCOMPATIBILITY.
   795 
   796   - Renamed predicate 'Quotient' to 'Quotient3', and renamed theorems
   797     accordingly, INCOMPATIBILITY.
   798 
   799 * New diagnostic command 'find_unused_assms' to find potentially
   800 superfluous assumptions in theorems using Quickcheck.
   801 
   802 * Quickcheck:
   803 
   804   - Quickcheck returns variable assignments as counterexamples, which
   805     allows to reveal the underspecification of functions under test.
   806     For example, refuting "hd xs = x", it presents the variable
   807     assignment xs = [] and x = a1 as a counterexample, assuming that
   808     any property is false whenever "hd []" occurs in it.
   809 
   810     These counterexample are marked as potentially spurious, as
   811     Quickcheck also returns "xs = []" as a counterexample to the
   812     obvious theorem "hd xs = hd xs".
   813 
   814     After finding a potentially spurious counterexample, Quickcheck
   815     continues searching for genuine ones.
   816 
   817     By default, Quickcheck shows potentially spurious and genuine
   818     counterexamples. The option "genuine_only" sets quickcheck to only
   819     show genuine counterexamples.
   820 
   821   - The command 'quickcheck_generator' creates random and exhaustive
   822     value generators for a given type and operations.
   823 
   824     It generates values by using the operations as if they were
   825     constructors of that type.
   826 
   827   - Support for multisets.
   828 
   829   - Added "use_subtype" options.
   830 
   831   - Added "quickcheck_locale" configuration to specify how to process
   832     conjectures in a locale context.
   833 
   834 * Nitpick: Fixed infinite loop caused by the 'peephole_optim' option
   835 and affecting 'rat' and 'real'.
   836 
   837 * Sledgehammer:
   838   - Integrated more tightly with SPASS, as described in the ITP 2012
   839     paper "More SPASS with Isabelle".
   840   - Made it try "smt" as a fallback if "metis" fails or times out.
   841   - Added support for the following provers: Alt-Ergo (via Why3 and
   842     TFF1), iProver, iProver-Eq.
   843   - Sped up the minimizer.
   844   - Added "lam_trans", "uncurry_aliases", and "minimize" options.
   845   - Renamed "slicing" ("no_slicing") option to "slice" ("dont_slice").
   846   - Renamed "sound" option to "strict".
   847 
   848 * Metis: Added possibility to specify lambda translations scheme as a
   849 parenthesized argument (e.g., "by (metis (lifting) ...)").
   850 
   851 * SMT: Renamed "smt_fixed" option to "smt_read_only_certificates".
   852 
   853 * Command 'try0': Renamed from 'try_methods'. INCOMPATIBILITY.
   854 
   855 * New "case_product" attribute to generate a case rule doing multiple
   856 case distinctions at the same time.  E.g.
   857 
   858   list.exhaust [case_product nat.exhaust]
   859 
   860 produces a rule which can be used to perform case distinction on both
   861 a list and a nat.
   862 
   863 * New "eventually_elim" method as a generalized variant of the
   864 eventually_elim* rules.  Supports structured proofs.
   865 
   866 * Typedef with implicit set definition is considered legacy.  Use
   867 "typedef (open)" form instead, which will eventually become the
   868 default.
   869 
   870 * Record: code generation can be switched off manually with
   871 
   872   declare [[record_coden = false]]  -- "default true"
   873 
   874 * Datatype: type parameters allow explicit sort constraints.
   875 
   876 * Concrete syntax for case expressions includes constraints for source
   877 positions, and thus produces Prover IDE markup for its bindings.
   878 INCOMPATIBILITY for old-style syntax translations that augment the
   879 pattern notation; e.g. see src/HOL/HOLCF/One.thy for translations of
   880 one_case.
   881 
   882 * Clarified attribute "mono_set": pure declaration without modifying
   883 the result of the fact expression.
   884 
   885 * More default pred/set conversions on a couple of relation operations
   886 and predicates.  Added powers of predicate relations.  Consolidation
   887 of some relation theorems:
   888 
   889   converse_def ~> converse_unfold
   890   rel_comp_def ~> relcomp_unfold
   891   symp_def ~> (modified, use symp_def and sym_def instead)
   892   transp_def ~> transp_trans
   893   Domain_def ~> Domain_unfold
   894   Range_def ~> Domain_converse [symmetric]
   895 
   896 Generalized theorems INF_INT_eq, INF_INT_eq2, SUP_UN_eq, SUP_UN_eq2.
   897 
   898 See theory "Relation" for examples for making use of pred/set
   899 conversions by means of attributes "to_set" and "to_pred".
   900 
   901 INCOMPATIBILITY.
   902 
   903 * Renamed facts about the power operation on relations, i.e., relpow
   904 to match the constant's name:
   905 
   906   rel_pow_1 ~> relpow_1
   907   rel_pow_0_I ~> relpow_0_I
   908   rel_pow_Suc_I ~> relpow_Suc_I
   909   rel_pow_Suc_I2 ~> relpow_Suc_I2
   910   rel_pow_0_E ~> relpow_0_E
   911   rel_pow_Suc_E ~> relpow_Suc_E
   912   rel_pow_E ~> relpow_E
   913   rel_pow_Suc_D2 ~> relpow_Suc_D2
   914   rel_pow_Suc_E2 ~> relpow_Suc_E2
   915   rel_pow_Suc_D2' ~> relpow_Suc_D2'
   916   rel_pow_E2 ~> relpow_E2
   917   rel_pow_add ~> relpow_add
   918   rel_pow_commute ~> relpow
   919   rel_pow_empty ~> relpow_empty:
   920   rtrancl_imp_UN_rel_pow ~> rtrancl_imp_UN_relpow
   921   rel_pow_imp_rtrancl ~> relpow_imp_rtrancl
   922   rtrancl_is_UN_rel_pow ~> rtrancl_is_UN_relpow
   923   rtrancl_imp_rel_pow ~> rtrancl_imp_relpow
   924   rel_pow_fun_conv ~> relpow_fun_conv
   925   rel_pow_finite_bounded1 ~> relpow_finite_bounded1
   926   rel_pow_finite_bounded ~> relpow_finite_bounded
   927   rtrancl_finite_eq_rel_pow ~> rtrancl_finite_eq_relpow
   928   trancl_finite_eq_rel_pow ~> trancl_finite_eq_relpow
   929   single_valued_rel_pow ~> single_valued_relpow
   930 
   931 INCOMPATIBILITY.
   932 
   933 * Theory Relation: Consolidated constant name for relation composition
   934 and corresponding theorem names:
   935 
   936   - Renamed constant rel_comp to relcomp.
   937 
   938   - Dropped abbreviation pred_comp. Use relcompp instead.
   939 
   940   - Renamed theorems:
   941 
   942     rel_compI ~> relcompI
   943     rel_compEpair ~> relcompEpair
   944     rel_compE ~> relcompE
   945     pred_comp_rel_comp_eq ~> relcompp_relcomp_eq
   946     rel_comp_empty1 ~> relcomp_empty1
   947     rel_comp_mono ~> relcomp_mono
   948     rel_comp_subset_Sigma ~> relcomp_subset_Sigma
   949     rel_comp_distrib ~> relcomp_distrib
   950     rel_comp_distrib2 ~> relcomp_distrib2
   951     rel_comp_UNION_distrib ~> relcomp_UNION_distrib
   952     rel_comp_UNION_distrib2 ~> relcomp_UNION_distrib2
   953     single_valued_rel_comp ~> single_valued_relcomp
   954     rel_comp_def ~> relcomp_unfold
   955     converse_rel_comp ~> converse_relcomp
   956     pred_compI ~> relcomppI
   957     pred_compE ~> relcomppE
   958     pred_comp_bot1 ~> relcompp_bot1
   959     pred_comp_bot2 ~> relcompp_bot2
   960     transp_pred_comp_less_eq ~> transp_relcompp_less_eq
   961     pred_comp_mono ~> relcompp_mono
   962     pred_comp_distrib ~> relcompp_distrib
   963     pred_comp_distrib2 ~> relcompp_distrib2
   964     converse_pred_comp ~> converse_relcompp
   965 
   966     finite_rel_comp ~> finite_relcomp
   967 
   968     set_rel_comp ~> set_relcomp
   969 
   970 INCOMPATIBILITY.
   971 
   972 * Theory Divides: Discontinued redundant theorems about div and mod.
   973 INCOMPATIBILITY, use the corresponding generic theorems instead.
   974 
   975   DIVISION_BY_ZERO ~> div_by_0, mod_by_0
   976   zdiv_self ~> div_self
   977   zmod_self ~> mod_self
   978   zdiv_zero ~> div_0
   979   zmod_zero ~> mod_0
   980   zdiv_zmod_equality ~> div_mod_equality2
   981   zdiv_zmod_equality2 ~> div_mod_equality
   982   zmod_zdiv_trivial ~> mod_div_trivial
   983   zdiv_zminus_zminus ~> div_minus_minus
   984   zmod_zminus_zminus ~> mod_minus_minus
   985   zdiv_zminus2 ~> div_minus_right
   986   zmod_zminus2 ~> mod_minus_right
   987   zdiv_minus1_right ~> div_minus1_right
   988   zmod_minus1_right ~> mod_minus1_right
   989   zdvd_mult_div_cancel ~> dvd_mult_div_cancel
   990   zmod_zmult1_eq ~> mod_mult_right_eq
   991   zpower_zmod ~> power_mod
   992   zdvd_zmod ~> dvd_mod
   993   zdvd_zmod_imp_zdvd ~> dvd_mod_imp_dvd
   994   mod_mult_distrib ~> mult_mod_left
   995   mod_mult_distrib2 ~> mult_mod_right
   996 
   997 * Removed redundant theorems nat_mult_2 and nat_mult_2_right; use
   998 generic mult_2 and mult_2_right instead. INCOMPATIBILITY.
   999 
  1000 * Finite_Set.fold now qualified.  INCOMPATIBILITY.
  1001 
  1002 * Consolidated theorem names concerning fold combinators:
  1003 
  1004   inf_INFI_fold_inf ~> inf_INF_fold_inf
  1005   sup_SUPR_fold_sup ~> sup_SUP_fold_sup
  1006   INFI_fold_inf ~> INF_fold_inf
  1007   SUPR_fold_sup ~> SUP_fold_sup
  1008   union_set ~> union_set_fold
  1009   minus_set ~> minus_set_fold
  1010   INFI_set_fold ~> INF_set_fold
  1011   SUPR_set_fold ~> SUP_set_fold
  1012   INF_code ~> INF_set_foldr
  1013   SUP_code ~> SUP_set_foldr
  1014   foldr.simps ~> foldr.simps (in point-free formulation)
  1015   foldr_fold_rev ~> foldr_conv_fold
  1016   foldl_fold ~> foldl_conv_fold
  1017   foldr_foldr ~> foldr_conv_foldl
  1018   foldl_foldr ~> foldl_conv_foldr
  1019   fold_set_remdups ~> fold_set_fold_remdups
  1020   fold_set ~> fold_set_fold
  1021   fold1_set ~> fold1_set_fold
  1022 
  1023 INCOMPATIBILITY.
  1024 
  1025 * Dropped rarely useful theorems concerning fold combinators:
  1026 foldl_apply, foldl_fun_comm, foldl_rev, fold_weak_invariant,
  1027 rev_foldl_cons, fold_set_remdups, fold_set, fold_set1,
  1028 concat_conv_foldl, foldl_weak_invariant, foldl_invariant,
  1029 foldr_invariant, foldl_absorb0, foldl_foldr1_lemma, foldl_foldr1,
  1030 listsum_conv_fold, listsum_foldl, sort_foldl_insort, foldl_assoc,
  1031 foldr_conv_foldl, start_le_sum, elem_le_sum, sum_eq_0_conv.
  1032 INCOMPATIBILITY.  For the common phrases "%xs. List.foldr plus xs 0"
  1033 and "List.foldl plus 0", prefer "List.listsum".  Otherwise it can be
  1034 useful to boil down "List.foldr" and "List.foldl" to "List.fold" by
  1035 unfolding "foldr_conv_fold" and "foldl_conv_fold".
  1036 
  1037 * Dropped lemmas minus_set_foldr, union_set_foldr, union_coset_foldr,
  1038 inter_coset_foldr, Inf_fin_set_foldr, Sup_fin_set_foldr,
  1039 Min_fin_set_foldr, Max_fin_set_foldr, Inf_set_foldr, Sup_set_foldr,
  1040 INF_set_foldr, SUP_set_foldr.  INCOMPATIBILITY.  Prefer corresponding
  1041 lemmas over fold rather than foldr, or make use of lemmas
  1042 fold_conv_foldr and fold_rev.
  1043 
  1044 * Congruence rules Option.map_cong and Option.bind_cong for recursion
  1045 through option types.
  1046 
  1047 * "Transitive_Closure.ntrancl": bounded transitive closure on
  1048 relations.
  1049 
  1050 * Constant "Set.not_member" now qualified.  INCOMPATIBILITY.
  1051 
  1052 * Theory Int: Discontinued many legacy theorems specific to type int.
  1053 INCOMPATIBILITY, use the corresponding generic theorems instead.
  1054 
  1055   zminus_zminus ~> minus_minus
  1056   zminus_0 ~> minus_zero
  1057   zminus_zadd_distrib ~> minus_add_distrib
  1058   zadd_commute ~> add_commute
  1059   zadd_assoc ~> add_assoc
  1060   zadd_left_commute ~> add_left_commute
  1061   zadd_ac ~> add_ac
  1062   zmult_ac ~> mult_ac
  1063   zadd_0 ~> add_0_left
  1064   zadd_0_right ~> add_0_right
  1065   zadd_zminus_inverse2 ~> left_minus
  1066   zmult_zminus ~> mult_minus_left
  1067   zmult_commute ~> mult_commute
  1068   zmult_assoc ~> mult_assoc
  1069   zadd_zmult_distrib ~> left_distrib
  1070   zadd_zmult_distrib2 ~> right_distrib
  1071   zdiff_zmult_distrib ~> left_diff_distrib
  1072   zdiff_zmult_distrib2 ~> right_diff_distrib
  1073   zmult_1 ~> mult_1_left
  1074   zmult_1_right ~> mult_1_right
  1075   zle_refl ~> order_refl
  1076   zle_trans ~> order_trans
  1077   zle_antisym ~> order_antisym
  1078   zle_linear ~> linorder_linear
  1079   zless_linear ~> linorder_less_linear
  1080   zadd_left_mono ~> add_left_mono
  1081   zadd_strict_right_mono ~> add_strict_right_mono
  1082   zadd_zless_mono ~> add_less_le_mono
  1083   int_0_less_1 ~> zero_less_one
  1084   int_0_neq_1 ~> zero_neq_one
  1085   zless_le ~> less_le
  1086   zpower_zadd_distrib ~> power_add
  1087   zero_less_zpower_abs_iff ~> zero_less_power_abs_iff
  1088   zero_le_zpower_abs ~> zero_le_power_abs
  1089 
  1090 * Theory Deriv: Renamed
  1091 
  1092   DERIV_nonneg_imp_nonincreasing ~> DERIV_nonneg_imp_nondecreasing
  1093 
  1094 * Theory Library/Multiset: Improved code generation of multisets.
  1095 
  1096 * Theory HOL/Library/Set_Algebras: Addition and multiplication on sets
  1097 are expressed via type classes again. The special syntax
  1098 \<oplus>/\<otimes> has been replaced by plain +/*. Removed constant
  1099 setsum_set, which is now subsumed by Big_Operators.setsum.
  1100 INCOMPATIBILITY.
  1101 
  1102 * Theory HOL/Library/Diagonalize has been removed. INCOMPATIBILITY,
  1103 use theory HOL/Library/Nat_Bijection instead.
  1104 
  1105 * Theory HOL/Library/RBT_Impl: Backing implementation of red-black
  1106 trees is now inside a type class context.  Names of affected
  1107 operations and lemmas have been prefixed by rbt_.  INCOMPATIBILITY for
  1108 theories working directly with raw red-black trees, adapt the names as
  1109 follows:
  1110 
  1111   Operations:
  1112   bulkload -> rbt_bulkload
  1113   del_from_left -> rbt_del_from_left
  1114   del_from_right -> rbt_del_from_right
  1115   del -> rbt_del
  1116   delete -> rbt_delete
  1117   ins -> rbt_ins
  1118   insert -> rbt_insert
  1119   insertw -> rbt_insert_with
  1120   insert_with_key -> rbt_insert_with_key
  1121   map_entry -> rbt_map_entry
  1122   lookup -> rbt_lookup
  1123   sorted -> rbt_sorted
  1124   tree_greater -> rbt_greater
  1125   tree_less -> rbt_less
  1126   tree_less_symbol -> rbt_less_symbol
  1127   union -> rbt_union
  1128   union_with -> rbt_union_with
  1129   union_with_key -> rbt_union_with_key
  1130 
  1131   Lemmas:
  1132   balance_left_sorted -> balance_left_rbt_sorted
  1133   balance_left_tree_greater -> balance_left_rbt_greater
  1134   balance_left_tree_less -> balance_left_rbt_less
  1135   balance_right_sorted -> balance_right_rbt_sorted
  1136   balance_right_tree_greater -> balance_right_rbt_greater
  1137   balance_right_tree_less -> balance_right_rbt_less
  1138   balance_sorted -> balance_rbt_sorted
  1139   balance_tree_greater -> balance_rbt_greater
  1140   balance_tree_less -> balance_rbt_less
  1141   bulkload_is_rbt -> rbt_bulkload_is_rbt
  1142   combine_sorted -> combine_rbt_sorted
  1143   combine_tree_greater -> combine_rbt_greater
  1144   combine_tree_less -> combine_rbt_less
  1145   delete_in_tree -> rbt_delete_in_tree
  1146   delete_is_rbt -> rbt_delete_is_rbt
  1147   del_from_left_tree_greater -> rbt_del_from_left_rbt_greater
  1148   del_from_left_tree_less -> rbt_del_from_left_rbt_less
  1149   del_from_right_tree_greater -> rbt_del_from_right_rbt_greater
  1150   del_from_right_tree_less -> rbt_del_from_right_rbt_less
  1151   del_in_tree -> rbt_del_in_tree
  1152   del_inv1_inv2 -> rbt_del_inv1_inv2
  1153   del_sorted -> rbt_del_rbt_sorted
  1154   del_tree_greater -> rbt_del_rbt_greater
  1155   del_tree_less -> rbt_del_rbt_less
  1156   dom_lookup_Branch -> dom_rbt_lookup_Branch
  1157   entries_lookup -> entries_rbt_lookup
  1158   finite_dom_lookup -> finite_dom_rbt_lookup
  1159   insert_sorted -> rbt_insert_rbt_sorted
  1160   insertw_is_rbt -> rbt_insertw_is_rbt
  1161   insertwk_is_rbt -> rbt_insertwk_is_rbt
  1162   insertwk_sorted -> rbt_insertwk_rbt_sorted
  1163   insertw_sorted -> rbt_insertw_rbt_sorted
  1164   ins_sorted -> ins_rbt_sorted
  1165   ins_tree_greater -> ins_rbt_greater
  1166   ins_tree_less -> ins_rbt_less
  1167   is_rbt_sorted -> is_rbt_rbt_sorted
  1168   lookup_balance -> rbt_lookup_balance
  1169   lookup_bulkload -> rbt_lookup_rbt_bulkload
  1170   lookup_delete -> rbt_lookup_rbt_delete
  1171   lookup_Empty -> rbt_lookup_Empty
  1172   lookup_from_in_tree -> rbt_lookup_from_in_tree
  1173   lookup_in_tree -> rbt_lookup_in_tree
  1174   lookup_ins -> rbt_lookup_ins
  1175   lookup_insert -> rbt_lookup_rbt_insert
  1176   lookup_insertw -> rbt_lookup_rbt_insertw
  1177   lookup_insertwk -> rbt_lookup_rbt_insertwk
  1178   lookup_keys -> rbt_lookup_keys
  1179   lookup_map -> rbt_lookup_map
  1180   lookup_map_entry -> rbt_lookup_rbt_map_entry
  1181   lookup_tree_greater -> rbt_lookup_rbt_greater
  1182   lookup_tree_less -> rbt_lookup_rbt_less
  1183   lookup_union -> rbt_lookup_rbt_union
  1184   map_entry_color_of -> rbt_map_entry_color_of
  1185   map_entry_inv1 -> rbt_map_entry_inv1
  1186   map_entry_inv2 -> rbt_map_entry_inv2
  1187   map_entry_is_rbt -> rbt_map_entry_is_rbt
  1188   map_entry_sorted -> rbt_map_entry_rbt_sorted
  1189   map_entry_tree_greater -> rbt_map_entry_rbt_greater
  1190   map_entry_tree_less -> rbt_map_entry_rbt_less
  1191   map_tree_greater -> map_rbt_greater
  1192   map_tree_less -> map_rbt_less
  1193   map_sorted -> map_rbt_sorted
  1194   paint_sorted -> paint_rbt_sorted
  1195   paint_lookup -> paint_rbt_lookup
  1196   paint_tree_greater -> paint_rbt_greater
  1197   paint_tree_less -> paint_rbt_less
  1198   sorted_entries -> rbt_sorted_entries
  1199   tree_greater_eq_trans -> rbt_greater_eq_trans
  1200   tree_greater_nit -> rbt_greater_nit
  1201   tree_greater_prop -> rbt_greater_prop
  1202   tree_greater_simps -> rbt_greater_simps
  1203   tree_greater_trans -> rbt_greater_trans
  1204   tree_less_eq_trans -> rbt_less_eq_trans
  1205   tree_less_nit -> rbt_less_nit
  1206   tree_less_prop -> rbt_less_prop
  1207   tree_less_simps -> rbt_less_simps
  1208   tree_less_trans -> rbt_less_trans
  1209   tree_ord_props -> rbt_ord_props
  1210   union_Branch -> rbt_union_Branch
  1211   union_is_rbt -> rbt_union_is_rbt
  1212   unionw_is_rbt -> rbt_unionw_is_rbt
  1213   unionwk_is_rbt -> rbt_unionwk_is_rbt
  1214   unionwk_sorted -> rbt_unionwk_rbt_sorted
  1215 
  1216 * Theory HOL/Library/Float: Floating point numbers are now defined as
  1217 a subset of the real numbers.  All operations are defined using the
  1218 lifing-framework and proofs use the transfer method.  INCOMPATIBILITY.
  1219 
  1220   Changed Operations:
  1221   float_abs -> abs
  1222   float_nprt -> nprt
  1223   float_pprt -> pprt
  1224   pow2 -> use powr
  1225   round_down -> float_round_down
  1226   round_up -> float_round_up
  1227   scale -> exponent
  1228 
  1229   Removed Operations:
  1230   ceiling_fl, lb_mult, lb_mod, ub_mult, ub_mod
  1231 
  1232   Renamed Lemmas:
  1233   abs_float_def -> Float.compute_float_abs
  1234   bitlen_ge0 -> bitlen_nonneg
  1235   bitlen.simps -> Float.compute_bitlen
  1236   float_components -> Float_mantissa_exponent
  1237   float_divl.simps -> Float.compute_float_divl
  1238   float_divr.simps -> Float.compute_float_divr
  1239   float_eq_odd -> mult_powr_eq_mult_powr_iff
  1240   float_power -> real_of_float_power
  1241   lapprox_posrat_def -> Float.compute_lapprox_posrat
  1242   lapprox_rat.simps -> Float.compute_lapprox_rat
  1243   le_float_def' -> Float.compute_float_le
  1244   le_float_def -> less_eq_float.rep_eq
  1245   less_float_def' -> Float.compute_float_less
  1246   less_float_def -> less_float.rep_eq
  1247   normfloat_def -> Float.compute_normfloat
  1248   normfloat_imp_odd_or_zero -> mantissa_not_dvd and mantissa_noteq_0
  1249   normfloat -> normfloat_def
  1250   normfloat_unique -> use normfloat_def
  1251   number_of_float_Float -> Float.compute_float_numeral, Float.compute_float_neg_numeral
  1252   one_float_def -> Float.compute_float_one
  1253   plus_float_def -> Float.compute_float_plus
  1254   rapprox_posrat_def -> Float.compute_rapprox_posrat
  1255   rapprox_rat.simps -> Float.compute_rapprox_rat
  1256   real_of_float_0 -> zero_float.rep_eq
  1257   real_of_float_1 -> one_float.rep_eq
  1258   real_of_float_abs -> abs_float.rep_eq
  1259   real_of_float_add -> plus_float.rep_eq
  1260   real_of_float_minus -> uminus_float.rep_eq
  1261   real_of_float_mult -> times_float.rep_eq
  1262   real_of_float_simp -> Float.rep_eq
  1263   real_of_float_sub -> minus_float.rep_eq
  1264   round_down.simps -> Float.compute_float_round_down
  1265   round_up.simps -> Float.compute_float_round_up
  1266   times_float_def -> Float.compute_float_times
  1267   uminus_float_def -> Float.compute_float_uminus
  1268   zero_float_def -> Float.compute_float_zero
  1269 
  1270   Lemmas not necessary anymore, use the transfer method:
  1271   bitlen_B0, bitlen_B1, bitlen_ge1, bitlen_Min, bitlen_Pls, float_divl,
  1272   float_divr, float_le_simp, float_less1_mantissa_bound,
  1273   float_less_simp, float_less_zero, float_le_zero,
  1274   float_pos_less1_e_neg, float_pos_m_pos, float_split, float_split2,
  1275   floor_pos_exp, lapprox_posrat, lapprox_posrat_bottom, lapprox_rat,
  1276   lapprox_rat_bottom, normalized_float, rapprox_posrat,
  1277   rapprox_posrat_le1, rapprox_rat, real_of_float_ge0_exp,
  1278   real_of_float_neg_exp, real_of_float_nge0_exp, round_down floor_fl,
  1279   round_up, zero_le_float, zero_less_float
  1280 
  1281 * New theory HOL/Library/DAList provides an abstract type for
  1282 association lists with distinct keys.
  1283 
  1284 * Session HOL/IMP: Added new theory of abstract interpretation of
  1285 annotated commands.
  1286 
  1287 * Session HOL-Import: Re-implementation from scratch is faster,
  1288 simpler, and more scalable.  Requires a proof bundle, which is
  1289 available as an external component.  Discontinued old (and mostly
  1290 dead) Importer for HOL4 and HOL Light.  INCOMPATIBILITY.
  1291 
  1292 * Session HOL-Word: Discontinued many redundant theorems specific to
  1293 type 'a word. INCOMPATIBILITY, use the corresponding generic theorems
  1294 instead.
  1295 
  1296   word_sub_alt ~> word_sub_wi
  1297   word_add_alt ~> word_add_def
  1298   word_mult_alt ~> word_mult_def
  1299   word_minus_alt ~> word_minus_def
  1300   word_0_alt ~> word_0_wi
  1301   word_1_alt ~> word_1_wi
  1302   word_add_0 ~> add_0_left
  1303   word_add_0_right ~> add_0_right
  1304   word_mult_1 ~> mult_1_left
  1305   word_mult_1_right ~> mult_1_right
  1306   word_add_commute ~> add_commute
  1307   word_add_assoc ~> add_assoc
  1308   word_add_left_commute ~> add_left_commute
  1309   word_mult_commute ~> mult_commute
  1310   word_mult_assoc ~> mult_assoc
  1311   word_mult_left_commute ~> mult_left_commute
  1312   word_left_distrib ~> left_distrib
  1313   word_right_distrib ~> right_distrib
  1314   word_left_minus ~> left_minus
  1315   word_diff_0_right ~> diff_0_right
  1316   word_diff_self ~> diff_self
  1317   word_sub_def ~> diff_minus
  1318   word_diff_minus ~> diff_minus
  1319   word_add_ac ~> add_ac
  1320   word_mult_ac ~> mult_ac
  1321   word_plus_ac0 ~> add_0_left add_0_right add_ac
  1322   word_times_ac1 ~> mult_1_left mult_1_right mult_ac
  1323   word_order_trans ~> order_trans
  1324   word_order_refl ~> order_refl
  1325   word_order_antisym ~> order_antisym
  1326   word_order_linear ~> linorder_linear
  1327   lenw1_zero_neq_one ~> zero_neq_one
  1328   word_number_of_eq ~> number_of_eq
  1329   word_of_int_add_hom ~> wi_hom_add
  1330   word_of_int_sub_hom ~> wi_hom_sub
  1331   word_of_int_mult_hom ~> wi_hom_mult
  1332   word_of_int_minus_hom ~> wi_hom_neg
  1333   word_of_int_succ_hom ~> wi_hom_succ
  1334   word_of_int_pred_hom ~> wi_hom_pred
  1335   word_of_int_0_hom ~> word_0_wi
  1336   word_of_int_1_hom ~> word_1_wi
  1337 
  1338 * Session HOL-Word: New proof method "word_bitwise" for splitting
  1339 machine word equalities and inequalities into logical circuits,
  1340 defined in HOL/Word/WordBitwise.thy.  Supports addition, subtraction,
  1341 multiplication, shifting by constants, bitwise operators and numeric
  1342 constants.  Requires fixed-length word types, not 'a word.  Solves
  1343 many standard word identities outright and converts more into first
  1344 order problems amenable to blast or similar.  See also examples in
  1345 HOL/Word/Examples/WordExamples.thy.
  1346 
  1347 * Session HOL-Probability: Introduced the type "'a measure" to
  1348 represent measures, this replaces the records 'a algebra and 'a
  1349 measure_space.  The locales based on subset_class now have two
  1350 locale-parameters the space \<Omega> and the set of measurable sets M.
  1351 The product of probability spaces uses now the same constant as the
  1352 finite product of sigma-finite measure spaces "PiM :: ('i => 'a)
  1353 measure".  Most constants are defined now outside of locales and gain
  1354 an additional parameter, like null_sets, almost_eventually or \<mu>'.
  1355 Measure space constructions for distributions and densities now got
  1356 their own constants distr and density.  Instead of using locales to
  1357 describe measure spaces with a finite space, the measure count_space
  1358 and point_measure is introduced.  INCOMPATIBILITY.
  1359 
  1360   Renamed constants:
  1361   measure -> emeasure
  1362   finite_measure.\<mu>' -> measure
  1363   product_algebra_generator -> prod_algebra
  1364   product_prob_space.emb -> prod_emb
  1365   product_prob_space.infprod_algebra -> PiM
  1366 
  1367   Removed locales:
  1368   completeable_measure_space
  1369   finite_measure_space
  1370   finite_prob_space
  1371   finite_product_finite_prob_space
  1372   finite_product_sigma_algebra
  1373   finite_sigma_algebra
  1374   measure_space
  1375   pair_finite_prob_space
  1376   pair_finite_sigma_algebra
  1377   pair_finite_space
  1378   pair_sigma_algebra
  1379   product_sigma_algebra
  1380 
  1381   Removed constants:
  1382   conditional_space
  1383   distribution -> use distr measure, or distributed predicate
  1384   image_space
  1385   joint_distribution -> use distr measure, or distributed predicate
  1386   pair_measure_generator
  1387   product_prob_space.infprod_algebra -> use PiM
  1388   subvimage
  1389 
  1390   Replacement theorems:
  1391   finite_additivity_sufficient -> ring_of_sets.countably_additiveI_finite
  1392   finite_measure.empty_measure -> measure_empty
  1393   finite_measure.finite_continuity_from_above -> finite_measure.finite_Lim_measure_decseq
  1394   finite_measure.finite_continuity_from_below -> finite_measure.finite_Lim_measure_incseq
  1395   finite_measure.finite_measure_countably_subadditive -> finite_measure.finite_measure_subadditive_countably
  1396   finite_measure.finite_measure_eq -> finite_measure.emeasure_eq_measure
  1397   finite_measure.finite_measure -> finite_measure.emeasure_finite
  1398   finite_measure.finite_measure_finite_singleton -> finite_measure.finite_measure_eq_setsum_singleton
  1399   finite_measure.positive_measure' -> measure_nonneg
  1400   finite_measure.real_measure -> finite_measure.emeasure_real
  1401   finite_product_prob_space.finite_measure_times -> finite_product_prob_space.finite_measure_PiM_emb
  1402   finite_product_sigma_algebra.in_P -> sets_PiM_I_finite
  1403   finite_product_sigma_algebra.P_empty -> space_PiM_empty, sets_PiM_empty
  1404   information_space.conditional_entropy_eq -> information_space.conditional_entropy_simple_distributed
  1405   information_space.conditional_entropy_positive -> information_space.conditional_entropy_nonneg_simple
  1406   information_space.conditional_mutual_information_eq_mutual_information -> information_space.conditional_mutual_information_eq_mutual_information_simple
  1407   information_space.conditional_mutual_information_generic_positive -> information_space.conditional_mutual_information_nonneg_simple
  1408   information_space.conditional_mutual_information_positive -> information_space.conditional_mutual_information_nonneg_simple
  1409   information_space.entropy_commute -> information_space.entropy_commute_simple
  1410   information_space.entropy_eq -> information_space.entropy_simple_distributed
  1411   information_space.entropy_generic_eq -> information_space.entropy_simple_distributed
  1412   information_space.entropy_positive -> information_space.entropy_nonneg_simple
  1413   information_space.entropy_uniform_max -> information_space.entropy_uniform
  1414   information_space.KL_eq_0_imp -> information_space.KL_eq_0_iff_eq
  1415   information_space.KL_eq_0 -> information_space.KL_same_eq_0
  1416   information_space.KL_ge_0 -> information_space.KL_nonneg
  1417   information_space.mutual_information_eq -> information_space.mutual_information_simple_distributed
  1418   information_space.mutual_information_positive -> information_space.mutual_information_nonneg_simple
  1419   Int_stable_cuboids -> Int_stable_atLeastAtMost
  1420   Int_stable_product_algebra_generator -> positive_integral
  1421   measure_preserving -> equality "distr M N f = N" "f : measurable M N"
  1422   measure_space.additive -> emeasure_additive
  1423   measure_space.AE_iff_null_set -> AE_iff_null
  1424   measure_space.almost_everywhere_def -> eventually_ae_filter
  1425   measure_space.almost_everywhere_vimage -> AE_distrD
  1426   measure_space.continuity_from_above -> INF_emeasure_decseq
  1427   measure_space.continuity_from_above_Lim -> Lim_emeasure_decseq
  1428   measure_space.continuity_from_below_Lim -> Lim_emeasure_incseq
  1429   measure_space.continuity_from_below -> SUP_emeasure_incseq
  1430   measure_space_density -> emeasure_density
  1431   measure_space.density_is_absolutely_continuous -> absolutely_continuousI_density
  1432   measure_space.integrable_vimage -> integrable_distr
  1433   measure_space.integral_translated_density -> integral_density
  1434   measure_space.integral_vimage -> integral_distr
  1435   measure_space.measure_additive -> plus_emeasure
  1436   measure_space.measure_compl -> emeasure_compl
  1437   measure_space.measure_countable_increasing -> emeasure_countable_increasing
  1438   measure_space.measure_countably_subadditive -> emeasure_subadditive_countably
  1439   measure_space.measure_decseq -> decseq_emeasure
  1440   measure_space.measure_Diff -> emeasure_Diff
  1441   measure_space.measure_Diff_null_set -> emeasure_Diff_null_set
  1442   measure_space.measure_eq_0 -> emeasure_eq_0
  1443   measure_space.measure_finitely_subadditive -> emeasure_subadditive_finite
  1444   measure_space.measure_finite_singleton -> emeasure_eq_setsum_singleton
  1445   measure_space.measure_incseq -> incseq_emeasure
  1446   measure_space.measure_insert -> emeasure_insert
  1447   measure_space.measure_mono -> emeasure_mono
  1448   measure_space.measure_not_negative -> emeasure_not_MInf
  1449   measure_space.measure_preserving_Int_stable -> measure_eqI_generator_eq
  1450   measure_space.measure_setsum -> setsum_emeasure
  1451   measure_space.measure_setsum_split -> setsum_emeasure_cover
  1452   measure_space.measure_space_vimage -> emeasure_distr
  1453   measure_space.measure_subadditive_finite -> emeasure_subadditive_finite
  1454   measure_space.measure_subadditive -> subadditive
  1455   measure_space.measure_top -> emeasure_space
  1456   measure_space.measure_UN_eq_0 -> emeasure_UN_eq_0
  1457   measure_space.measure_Un_null_set -> emeasure_Un_null_set
  1458   measure_space.positive_integral_translated_density -> positive_integral_density
  1459   measure_space.positive_integral_vimage -> positive_integral_distr
  1460   measure_space.real_continuity_from_above -> Lim_measure_decseq
  1461   measure_space.real_continuity_from_below -> Lim_measure_incseq
  1462   measure_space.real_measure_countably_subadditive -> measure_subadditive_countably
  1463   measure_space.real_measure_Diff -> measure_Diff
  1464   measure_space.real_measure_finite_Union -> measure_finite_Union
  1465   measure_space.real_measure_setsum_singleton -> measure_eq_setsum_singleton
  1466   measure_space.real_measure_subadditive -> measure_subadditive
  1467   measure_space.real_measure_Union -> measure_Union
  1468   measure_space.real_measure_UNION -> measure_UNION
  1469   measure_space.simple_function_vimage -> simple_function_comp
  1470   measure_space.simple_integral_vimage -> simple_integral_distr
  1471   measure_space.simple_integral_vimage -> simple_integral_distr
  1472   measure_unique_Int_stable -> measure_eqI_generator_eq
  1473   measure_unique_Int_stable_vimage -> measure_eqI_generator_eq
  1474   pair_sigma_algebra.measurable_cut_fst -> sets_Pair1
  1475   pair_sigma_algebra.measurable_cut_snd -> sets_Pair2
  1476   pair_sigma_algebra.measurable_pair_image_fst -> measurable_Pair1
  1477   pair_sigma_algebra.measurable_pair_image_snd -> measurable_Pair2
  1478   pair_sigma_algebra.measurable_product_swap -> measurable_pair_swap_iff
  1479   pair_sigma_algebra.pair_sigma_algebra_measurable -> measurable_pair_swap
  1480   pair_sigma_algebra.pair_sigma_algebra_swap_measurable -> measurable_pair_swap'
  1481   pair_sigma_algebra.sets_swap -> sets_pair_swap
  1482   pair_sigma_finite.measure_cut_measurable_fst -> pair_sigma_finite.measurable_emeasure_Pair1
  1483   pair_sigma_finite.measure_cut_measurable_snd -> pair_sigma_finite.measurable_emeasure_Pair2
  1484   pair_sigma_finite.measure_preserving_swap -> pair_sigma_finite.distr_pair_swap
  1485   pair_sigma_finite.pair_measure_alt2 -> pair_sigma_finite.emeasure_pair_measure_alt2
  1486   pair_sigma_finite.pair_measure_alt -> pair_sigma_finite.emeasure_pair_measure_alt
  1487   pair_sigma_finite.pair_measure_times -> pair_sigma_finite.emeasure_pair_measure_Times
  1488   prob_space.indep_distribution_eq_measure -> prob_space.indep_vars_iff_distr_eq_PiM
  1489   prob_space.indep_var_distributionD -> prob_space.indep_var_distribution_eq
  1490   prob_space.measure_space_1 -> prob_space.emeasure_space_1
  1491   prob_space.prob_space_vimage -> prob_space_distr
  1492   prob_space.random_variable_restrict -> measurable_restrict
  1493   prob_space_unique_Int_stable -> measure_eqI_prob_space
  1494   product_algebraE -> prod_algebraE_all
  1495   product_algebra_generator_der -> prod_algebra_eq_finite
  1496   product_algebra_generator_into_space -> prod_algebra_sets_into_space
  1497   product_algebraI -> sets_PiM_I_finite
  1498   product_measure_exists -> product_sigma_finite.sigma_finite
  1499   product_prob_space.finite_index_eq_finite_product -> product_prob_space.sets_PiM_generator
  1500   product_prob_space.finite_measure_infprod_emb_Pi -> product_prob_space.measure_PiM_emb
  1501   product_prob_space.infprod_spec -> product_prob_space.emeasure_PiM_emb_not_empty
  1502   product_prob_space.measurable_component -> measurable_component_singleton
  1503   product_prob_space.measurable_emb -> measurable_prod_emb
  1504   product_prob_space.measurable_into_infprod_algebra -> measurable_PiM_single
  1505   product_prob_space.measurable_singleton_infprod -> measurable_component_singleton
  1506   product_prob_space.measure_emb -> emeasure_prod_emb
  1507   product_prob_space.measure_preserving_restrict -> product_prob_space.distr_restrict
  1508   product_sigma_algebra.product_algebra_into_space -> space_closed
  1509   product_sigma_finite.measure_fold -> product_sigma_finite.distr_merge
  1510   product_sigma_finite.measure_preserving_component_singelton -> product_sigma_finite.distr_singleton
  1511   product_sigma_finite.measure_preserving_merge -> product_sigma_finite.distr_merge
  1512   sequence_space.measure_infprod -> sequence_space.measure_PiM_countable
  1513   sets_product_algebra -> sets_PiM
  1514   sigma_algebra.measurable_sigma -> measurable_measure_of
  1515   sigma_finite_measure.disjoint_sigma_finite -> sigma_finite_disjoint
  1516   sigma_finite_measure.RN_deriv_vimage -> sigma_finite_measure.RN_deriv_distr
  1517   sigma_product_algebra_sigma_eq -> sigma_prod_algebra_sigma_eq
  1518   space_product_algebra -> space_PiM
  1519 
  1520 * Session HOL-TPTP: support to parse and import TPTP problems (all
  1521 languages) into Isabelle/HOL.
  1522 
  1523 
  1524 *** FOL ***
  1525 
  1526 * New "case_product" attribute (see HOL).
  1527 
  1528 
  1529 *** ZF ***
  1530 
  1531 * Greater support for structured proofs involving induction or case
  1532 analysis.
  1533 
  1534 * Much greater use of mathematical symbols.
  1535 
  1536 * Removal of many ML theorem bindings.  INCOMPATIBILITY.
  1537 
  1538 
  1539 *** ML ***
  1540 
  1541 * Antiquotation @{keyword "name"} produces a parser for outer syntax
  1542 from a minor keyword introduced via theory header declaration.
  1543 
  1544 * Antiquotation @{command_spec "name"} produces the
  1545 Outer_Syntax.command_spec from a major keyword introduced via theory
  1546 header declaration; it can be passed to Outer_Syntax.command etc.
  1547 
  1548 * Local_Theory.define no longer hard-wires default theorem name
  1549 "foo_def", but retains the binding as given.  If that is Binding.empty
  1550 / Attrib.empty_binding, the result is not registered as user-level
  1551 fact.  The Local_Theory.define_internal variant allows to specify a
  1552 non-empty name (used for the foundation in the background theory),
  1553 while omitting the fact binding in the user-context.  Potential
  1554 INCOMPATIBILITY for derived definitional packages: need to specify
  1555 naming policy for primitive definitions more explicitly.
  1556 
  1557 * Renamed Thm.capply to Thm.apply, and Thm.cabs to Thm.lambda in
  1558 conformance with similar operations in structure Term and Logic.
  1559 
  1560 * Antiquotation @{attributes [...]} embeds attribute source
  1561 representation into the ML text, which is particularly useful with
  1562 declarations like Local_Theory.note.
  1563 
  1564 * Structure Proof_Context follows standard naming scheme.  Old
  1565 ProofContext has been discontinued.  INCOMPATIBILITY.
  1566 
  1567 * Refined Local_Theory.declaration {syntax, pervasive}, with subtle
  1568 change of semantics: update is applied to auxiliary local theory
  1569 context as well.
  1570 
  1571 * Modernized some old-style infix operations:
  1572 
  1573   addeqcongs    ~> Simplifier.add_eqcong
  1574   deleqcongs    ~> Simplifier.del_eqcong
  1575   addcongs      ~> Simplifier.add_cong
  1576   delcongs      ~> Simplifier.del_cong
  1577   setmksimps    ~> Simplifier.set_mksimps
  1578   setmkcong     ~> Simplifier.set_mkcong
  1579   setmksym      ~> Simplifier.set_mksym
  1580   setmkeqTrue   ~> Simplifier.set_mkeqTrue
  1581   settermless   ~> Simplifier.set_termless
  1582   setsubgoaler  ~> Simplifier.set_subgoaler
  1583   addsplits     ~> Splitter.add_split
  1584   delsplits     ~> Splitter.del_split
  1585 
  1586 
  1587 *** System ***
  1588 
  1589 * USER_HOME settings variable points to cross-platform user home
  1590 directory, which coincides with HOME on POSIX systems only.  Likewise,
  1591 the Isabelle path specification "~" now expands to $USER_HOME, instead
  1592 of former $HOME.  A different default for USER_HOME may be set
  1593 explicitly in shell environment, before Isabelle settings are
  1594 evaluated.  Minor INCOMPATIBILITY: need to adapt Isabelle path where
  1595 the generic user home was intended.
  1596 
  1597 * ISABELLE_HOME_WINDOWS refers to ISABELLE_HOME in windows file name
  1598 notation, which is useful for the jEdit file browser, for example.
  1599 
  1600 * ISABELLE_JDK_HOME settings variable points to JDK with javac and jar
  1601 (not just JRE).
  1602 
  1603 
  1604 
  1605 New in Isabelle2011-1 (October 2011)
  1606 ------------------------------------
  1607 
  1608 *** General ***
  1609 
  1610 * Improved Isabelle/jEdit Prover IDE (PIDE), which can be invoked as
  1611 "isabelle jedit" or "ISABELLE_HOME/Isabelle" on the command line.
  1612 
  1613   - Management of multiple theory files directly from the editor
  1614     buffer store -- bypassing the file-system (no requirement to save
  1615     files for checking).
  1616 
  1617   - Markup of formal entities within the text buffer, with semantic
  1618     highlighting, tooltips and hyperlinks to jump to defining source
  1619     positions.
  1620 
  1621   - Improved text rendering, with sub/superscripts in the source
  1622     buffer (including support for copy/paste wrt. output panel, HTML
  1623     theory output and other non-Isabelle text boxes).
  1624 
  1625   - Refined scheduling of proof checking and printing of results,
  1626     based on interactive editor view.  (Note: jEdit folding and
  1627     narrowing allows to restrict buffer perspectives explicitly.)
  1628 
  1629   - Reduced CPU performance requirements, usable on machines with few
  1630     cores.
  1631 
  1632   - Reduced memory requirements due to pruning of unused document
  1633     versions (garbage collection).
  1634 
  1635 See also ~~/src/Tools/jEdit/README.html for further information,
  1636 including some remaining limitations.
  1637 
  1638 * Theory loader: source files are exclusively located via the master
  1639 directory of each theory node (where the .thy file itself resides).
  1640 The global load path (such as src/HOL/Library) has been discontinued.
  1641 Note that the path element ~~ may be used to reference theories in the
  1642 Isabelle home folder -- for instance, "~~/src/HOL/Library/FuncSet".
  1643 INCOMPATIBILITY.
  1644 
  1645 * Theory loader: source files are identified by content via SHA1
  1646 digests.  Discontinued former path/modtime identification and optional
  1647 ISABELLE_FILE_IDENT plugin scripts.
  1648 
  1649 * Parallelization of nested Isar proofs is subject to
  1650 Goal.parallel_proofs_threshold (default 100).  See also isabelle
  1651 usedir option -Q.
  1652 
  1653 * Name space: former unsynchronized references are now proper
  1654 configuration options, with more conventional names:
  1655 
  1656   long_names   ~> names_long
  1657   short_names  ~> names_short
  1658   unique_names ~> names_unique
  1659 
  1660 Minor INCOMPATIBILITY, need to declare options in context like this:
  1661 
  1662   declare [[names_unique = false]]
  1663 
  1664 * Literal facts `prop` may contain dummy patterns, e.g. `_ = _`.  Note
  1665 that the result needs to be unique, which means fact specifications
  1666 may have to be refined after enriching a proof context.
  1667 
  1668 * Attribute "case_names" has been refined: the assumptions in each case
  1669 can be named now by following the case name with [name1 name2 ...].
  1670 
  1671 * Isabelle/Isar reference manual has been updated and extended:
  1672   - "Synopsis" provides a catalog of main Isar language concepts.
  1673   - Formal references in syntax diagrams, via @{rail} antiquotation.
  1674   - Updated material from classic "ref" manual, notably about
  1675     "Classical Reasoner".
  1676 
  1677 
  1678 *** HOL ***
  1679 
  1680 * Class bot and top require underlying partial order rather than
  1681 preorder: uniqueness of bot and top is guaranteed.  INCOMPATIBILITY.
  1682 
  1683 * Class complete_lattice: generalized a couple of lemmas from sets;
  1684 generalized theorems INF_cong and SUP_cong.  New type classes for
  1685 complete boolean algebras and complete linear orders.  Lemmas
  1686 Inf_less_iff, less_Sup_iff, INF_less_iff, less_SUP_iff now reside in
  1687 class complete_linorder.
  1688 
  1689 Changed proposition of lemmas Inf_bool_def, Sup_bool_def, Inf_fun_def,
  1690 Sup_fun_def, Inf_apply, Sup_apply.
  1691 
  1692 Removed redundant lemmas (the right hand side gives hints how to
  1693 replace them for (metis ...), or (simp only: ...) proofs):
  1694 
  1695   Inf_singleton ~> Inf_insert [where A="{}", unfolded Inf_empty inf_top_right]
  1696   Sup_singleton ~> Sup_insert [where A="{}", unfolded Sup_empty sup_bot_right]
  1697   Inf_binary ~> Inf_insert, Inf_empty, and inf_top_right
  1698   Sup_binary ~> Sup_insert, Sup_empty, and sup_bot_right
  1699   Int_eq_Inter ~> Inf_insert, Inf_empty, and inf_top_right
  1700   Un_eq_Union ~> Sup_insert, Sup_empty, and sup_bot_right
  1701   Inter_def ~> INF_def, image_def
  1702   Union_def ~> SUP_def, image_def
  1703   INT_eq ~> INF_def, and image_def
  1704   UN_eq ~> SUP_def, and image_def
  1705   INF_subset ~> INF_superset_mono [OF _ order_refl]
  1706 
  1707 More consistent and comprehensive names:
  1708 
  1709   INTER_eq_Inter_image ~> INF_def
  1710   UNION_eq_Union_image ~> SUP_def
  1711   INFI_def ~> INF_def
  1712   SUPR_def ~> SUP_def
  1713   INF_leI ~> INF_lower
  1714   INF_leI2 ~> INF_lower2
  1715   le_INFI ~> INF_greatest
  1716   le_SUPI ~> SUP_upper
  1717   le_SUPI2 ~> SUP_upper2
  1718   SUP_leI ~> SUP_least
  1719   INFI_bool_eq ~> INF_bool_eq
  1720   SUPR_bool_eq ~> SUP_bool_eq
  1721   INFI_apply ~> INF_apply
  1722   SUPR_apply ~> SUP_apply
  1723   INTER_def ~> INTER_eq
  1724   UNION_def ~> UNION_eq
  1725 
  1726 INCOMPATIBILITY.
  1727 
  1728 * Renamed theory Complete_Lattice to Complete_Lattices.
  1729 INCOMPATIBILITY.
  1730 
  1731 * Theory Complete_Lattices: lemmas Inf_eq_top_iff, INF_eq_top_iff,
  1732 INF_image, Inf_insert, INF_top, Inf_top_conv, INF_top_conv, SUP_bot,
  1733 Sup_bot_conv, SUP_bot_conv, Sup_eq_top_iff, SUP_eq_top_iff, SUP_image,
  1734 Sup_insert are now declared as [simp].  INCOMPATIBILITY.
  1735 
  1736 * Theory Lattice: lemmas compl_inf_bot, compl_le_comp_iff,
  1737 compl_sup_top, inf_idem, inf_left_idem, inf_sup_absorb, sup_idem,
  1738 sup_inf_absob, sup_left_idem are now declared as [simp].  Minor
  1739 INCOMPATIBILITY.
  1740 
  1741 * Added syntactic classes "inf" and "sup" for the respective
  1742 constants.  INCOMPATIBILITY: Changes in the argument order of the
  1743 (mostly internal) locale predicates for some derived classes.
  1744 
  1745 * Theorem collections ball_simps and bex_simps do not contain theorems
  1746 referring to UNION any longer; these have been moved to collection
  1747 UN_ball_bex_simps.  INCOMPATIBILITY.
  1748 
  1749 * Theory Archimedean_Field: floor now is defined as parameter of a
  1750 separate type class floor_ceiling.
  1751 
  1752 * Theory Finite_Set: more coherent development of fold_set locales:
  1753 
  1754     locale fun_left_comm ~> locale comp_fun_commute
  1755     locale fun_left_comm_idem ~> locale comp_fun_idem
  1756 
  1757 Both use point-free characterization; interpretation proofs may need
  1758 adjustment.  INCOMPATIBILITY.
  1759 
  1760 * Theory Limits: Type "'a net" has been renamed to "'a filter", in
  1761 accordance with standard mathematical terminology. INCOMPATIBILITY.
  1762 
  1763 * Theory Complex_Main: The locale interpretations for the
  1764 bounded_linear and bounded_bilinear locales have been removed, in
  1765 order to reduce the number of duplicate lemmas. Users must use the
  1766 original names for distributivity theorems, potential INCOMPATIBILITY.
  1767 
  1768   divide.add ~> add_divide_distrib
  1769   divide.diff ~> diff_divide_distrib
  1770   divide.setsum ~> setsum_divide_distrib
  1771   mult.add_right ~> right_distrib
  1772   mult.diff_right ~> right_diff_distrib
  1773   mult_right.setsum ~> setsum_right_distrib
  1774   mult_left.diff ~> left_diff_distrib
  1775 
  1776 * Theory Complex_Main: Several redundant theorems have been removed or
  1777 replaced by more general versions. INCOMPATIBILITY.
  1778 
  1779   real_diff_def ~> minus_real_def
  1780   real_divide_def ~> divide_real_def
  1781   real_less_def ~> less_le
  1782   real_abs_def ~> abs_real_def
  1783   real_sgn_def ~> sgn_real_def
  1784   real_mult_commute ~> mult_commute
  1785   real_mult_assoc ~> mult_assoc
  1786   real_mult_1 ~> mult_1_left
  1787   real_add_mult_distrib ~> left_distrib
  1788   real_zero_not_eq_one ~> zero_neq_one
  1789   real_mult_inverse_left ~> left_inverse
  1790   INVERSE_ZERO ~> inverse_zero
  1791   real_le_refl ~> order_refl
  1792   real_le_antisym ~> order_antisym
  1793   real_le_trans ~> order_trans
  1794   real_le_linear ~> linear
  1795   real_le_eq_diff ~> le_iff_diff_le_0
  1796   real_add_left_mono ~> add_left_mono
  1797   real_mult_order ~> mult_pos_pos
  1798   real_mult_less_mono2 ~> mult_strict_left_mono
  1799   real_of_int_real_of_nat ~> real_of_int_of_nat_eq
  1800   real_0_le_divide_iff ~> zero_le_divide_iff
  1801   realpow_two_disj ~> power2_eq_iff
  1802   real_squared_diff_one_factored ~> square_diff_one_factored
  1803   realpow_two_diff ~> square_diff_square_factored
  1804   reals_complete2 ~> complete_real
  1805   real_sum_squared_expand ~> power2_sum
  1806   exp_ln_eq ~> ln_unique
  1807   expi_add ~> exp_add
  1808   expi_zero ~> exp_zero
  1809   lemma_DERIV_subst ~> DERIV_cong
  1810   LIMSEQ_Zfun_iff ~> tendsto_Zfun_iff
  1811   LIMSEQ_const ~> tendsto_const
  1812   LIMSEQ_norm ~> tendsto_norm
  1813   LIMSEQ_add ~> tendsto_add
  1814   LIMSEQ_minus ~> tendsto_minus
  1815   LIMSEQ_minus_cancel ~> tendsto_minus_cancel
  1816   LIMSEQ_diff ~> tendsto_diff
  1817   bounded_linear.LIMSEQ ~> bounded_linear.tendsto
  1818   bounded_bilinear.LIMSEQ ~> bounded_bilinear.tendsto
  1819   LIMSEQ_mult ~> tendsto_mult
  1820   LIMSEQ_inverse ~> tendsto_inverse
  1821   LIMSEQ_divide ~> tendsto_divide
  1822   LIMSEQ_pow ~> tendsto_power
  1823   LIMSEQ_setsum ~> tendsto_setsum
  1824   LIMSEQ_setprod ~> tendsto_setprod
  1825   LIMSEQ_norm_zero ~> tendsto_norm_zero_iff
  1826   LIMSEQ_rabs_zero ~> tendsto_rabs_zero_iff
  1827   LIMSEQ_imp_rabs ~> tendsto_rabs
  1828   LIMSEQ_add_minus ~> tendsto_add [OF _ tendsto_minus]
  1829   LIMSEQ_add_const ~> tendsto_add [OF _ tendsto_const]
  1830   LIMSEQ_diff_const ~> tendsto_diff [OF _ tendsto_const]
  1831   LIMSEQ_Complex ~> tendsto_Complex
  1832   LIM_ident ~> tendsto_ident_at
  1833   LIM_const ~> tendsto_const
  1834   LIM_add ~> tendsto_add
  1835   LIM_add_zero ~> tendsto_add_zero
  1836   LIM_minus ~> tendsto_minus
  1837   LIM_diff ~> tendsto_diff
  1838   LIM_norm ~> tendsto_norm
  1839   LIM_norm_zero ~> tendsto_norm_zero
  1840   LIM_norm_zero_cancel ~> tendsto_norm_zero_cancel
  1841   LIM_norm_zero_iff ~> tendsto_norm_zero_iff
  1842   LIM_rabs ~> tendsto_rabs
  1843   LIM_rabs_zero ~> tendsto_rabs_zero
  1844   LIM_rabs_zero_cancel ~> tendsto_rabs_zero_cancel
  1845   LIM_rabs_zero_iff ~> tendsto_rabs_zero_iff
  1846   LIM_compose ~> tendsto_compose
  1847   LIM_mult ~> tendsto_mult
  1848   LIM_scaleR ~> tendsto_scaleR
  1849   LIM_of_real ~> tendsto_of_real
  1850   LIM_power ~> tendsto_power
  1851   LIM_inverse ~> tendsto_inverse
  1852   LIM_sgn ~> tendsto_sgn
  1853   isCont_LIM_compose ~> isCont_tendsto_compose
  1854   bounded_linear.LIM ~> bounded_linear.tendsto
  1855   bounded_linear.LIM_zero ~> bounded_linear.tendsto_zero
  1856   bounded_bilinear.LIM ~> bounded_bilinear.tendsto
  1857   bounded_bilinear.LIM_prod_zero ~> bounded_bilinear.tendsto_zero
  1858   bounded_bilinear.LIM_left_zero ~> bounded_bilinear.tendsto_left_zero
  1859   bounded_bilinear.LIM_right_zero ~> bounded_bilinear.tendsto_right_zero
  1860   LIM_inverse_fun ~> tendsto_inverse [OF tendsto_ident_at]
  1861 
  1862 * Theory Complex_Main: The definition of infinite series was
  1863 generalized.  Now it is defined on the type class {topological_space,
  1864 comm_monoid_add}.  Hence it is useable also for extended real numbers.
  1865 
  1866 * Theory Complex_Main: The complex exponential function "expi" is now
  1867 a type-constrained abbreviation for "exp :: complex => complex"; thus
  1868 several polymorphic lemmas about "exp" are now applicable to "expi".
  1869 
  1870 * Code generation:
  1871 
  1872   - Theory Library/Code_Char_ord provides native ordering of
  1873     characters in the target language.
  1874 
  1875   - Commands code_module and code_library are legacy, use export_code
  1876     instead.
  1877 
  1878   - Method "evaluation" is legacy, use method "eval" instead.
  1879 
  1880   - Legacy evaluator "SML" is deactivated by default.  May be
  1881     reactivated by the following theory command:
  1882 
  1883       setup {* Value.add_evaluator ("SML", Codegen.eval_term) *}
  1884 
  1885 * Declare ext [intro] by default.  Rare INCOMPATIBILITY.
  1886 
  1887 * New proof method "induction" that gives induction hypotheses the
  1888 name "IH", thus distinguishing them from further hypotheses that come
  1889 from rule induction.  The latter are still called "hyps".  Method
  1890 "induction" is a thin wrapper around "induct" and follows the same
  1891 syntax.
  1892 
  1893 * Method "fastsimp" has been renamed to "fastforce", but "fastsimp" is
  1894 still available as a legacy feature for some time.
  1895 
  1896 * Nitpick:
  1897   - Added "need" and "total_consts" options.
  1898   - Reintroduced "show_skolems" option by popular demand.
  1899   - Renamed attribute: nitpick_def ~> nitpick_unfold.
  1900     INCOMPATIBILITY.
  1901 
  1902 * Sledgehammer:
  1903   - Use quasi-sound (and efficient) translations by default.
  1904   - Added support for the following provers: E-ToFoF, LEO-II,
  1905     Satallax, SNARK, Waldmeister, and Z3 with TPTP syntax.
  1906   - Automatically preplay and minimize proofs before showing them if
  1907     this can be done within reasonable time.
  1908   - sledgehammer available_provers ~> sledgehammer supported_provers.
  1909     INCOMPATIBILITY.
  1910   - Added "preplay_timeout", "slicing", "type_enc", "sound",
  1911     "max_mono_iters", and "max_new_mono_instances" options.
  1912   - Removed "explicit_apply" and "full_types" options as well as "Full
  1913     Types" Proof General menu item. INCOMPATIBILITY.
  1914 
  1915 * Metis:
  1916   - Removed "metisF" -- use "metis" instead. INCOMPATIBILITY.
  1917   - Obsoleted "metisFT" -- use "metis (full_types)" instead.
  1918     INCOMPATIBILITY.
  1919 
  1920 * Command 'try':
  1921   - Renamed 'try_methods' and added "simp:", "intro:", "dest:", and
  1922     "elim:" options. INCOMPATIBILITY.
  1923   - Introduced 'try' that not only runs 'try_methods' but also
  1924     'solve_direct', 'sledgehammer', 'quickcheck', and 'nitpick'.
  1925 
  1926 * Quickcheck:
  1927   - Added "eval" option to evaluate terms for the found counterexample
  1928     (currently only supported by the default (exhaustive) tester).
  1929   - Added post-processing of terms to obtain readable counterexamples
  1930     (currently only supported by the default (exhaustive) tester).
  1931   - New counterexample generator quickcheck[narrowing] enables
  1932     narrowing-based testing.  Requires the Glasgow Haskell compiler
  1933     with its installation location defined in the Isabelle settings
  1934     environment as ISABELLE_GHC.
  1935   - Removed quickcheck tester "SML" based on the SML code generator
  1936     (formly in HOL/Library).
  1937 
  1938 * Function package: discontinued option "tailrec".  INCOMPATIBILITY,
  1939 use 'partial_function' instead.
  1940 
  1941 * Theory Library/Extended_Reals replaces now the positive extended
  1942 reals found in probability theory. This file is extended by
  1943 Multivariate_Analysis/Extended_Real_Limits.
  1944 
  1945 * Theory Library/Old_Recdef: old 'recdef' package has been moved here,
  1946 from where it must be imported explicitly if it is really required.
  1947 INCOMPATIBILITY.
  1948 
  1949 * Theory Library/Wfrec: well-founded recursion combinator "wfrec" has
  1950 been moved here.  INCOMPATIBILITY.
  1951 
  1952 * Theory Library/Saturated provides type of numbers with saturated
  1953 arithmetic.
  1954 
  1955 * Theory Library/Product_Lattice defines a pointwise ordering for the
  1956 product type 'a * 'b, and provides instance proofs for various order
  1957 and lattice type classes.
  1958 
  1959 * Theory Library/Countable now provides the "countable_datatype" proof
  1960 method for proving "countable" class instances for datatypes.
  1961 
  1962 * Theory Library/Cset_Monad allows do notation for computable sets
  1963 (cset) via the generic monad ad-hoc overloading facility.
  1964 
  1965 * Library: Theories of common data structures are split into theories
  1966 for implementation, an invariant-ensuring type, and connection to an
  1967 abstract type. INCOMPATIBILITY.
  1968 
  1969   - RBT is split into RBT and RBT_Mapping.
  1970   - AssocList is split and renamed into AList and AList_Mapping.
  1971   - DList is split into DList_Impl, DList, and DList_Cset.
  1972   - Cset is split into Cset and List_Cset.
  1973 
  1974 * Theory Library/Nat_Infinity has been renamed to
  1975 Library/Extended_Nat, with name changes of the following types and
  1976 constants:
  1977 
  1978   type inat   ~> type enat
  1979   Fin         ~> enat
  1980   Infty       ~> infinity (overloaded)
  1981   iSuc        ~> eSuc
  1982   the_Fin     ~> the_enat
  1983 
  1984 Every theorem name containing "inat", "Fin", "Infty", or "iSuc" has
  1985 been renamed accordingly. INCOMPATIBILITY.
  1986 
  1987 * Session Multivariate_Analysis: The euclidean_space type class now
  1988 fixes a constant "Basis :: 'a set" consisting of the standard
  1989 orthonormal basis for the type. Users now have the option of
  1990 quantifying over this set instead of using the "basis" function, e.g.
  1991 "ALL x:Basis. P x" vs "ALL i<DIM('a). P (basis i)".
  1992 
  1993 * Session Multivariate_Analysis: Type "('a, 'b) cart" has been renamed
  1994 to "('a, 'b) vec" (the syntax "'a ^ 'b" remains unaffected). Constants
  1995 "Cart_nth" and "Cart_lambda" have been respectively renamed to
  1996 "vec_nth" and "vec_lambda"; theorems mentioning those names have
  1997 changed to match. Definition theorems for overloaded constants now use
  1998 the standard "foo_vec_def" naming scheme. A few other theorems have
  1999 been renamed as follows (INCOMPATIBILITY):
  2000 
  2001   Cart_eq          ~> vec_eq_iff
  2002   dist_nth_le_cart ~> dist_vec_nth_le
  2003   tendsto_vector   ~> vec_tendstoI
  2004   Cauchy_vector    ~> vec_CauchyI
  2005 
  2006 * Session Multivariate_Analysis: Several duplicate theorems have been
  2007 removed, and other theorems have been renamed or replaced with more
  2008 general versions. INCOMPATIBILITY.
  2009 
  2010   finite_choice ~> finite_set_choice
  2011   eventually_conjI ~> eventually_conj
  2012   eventually_and ~> eventually_conj_iff
  2013   eventually_false ~> eventually_False
  2014   setsum_norm ~> norm_setsum
  2015   Lim_sequentially ~> LIMSEQ_def
  2016   Lim_ident_at ~> LIM_ident
  2017   Lim_const ~> tendsto_const
  2018   Lim_cmul ~> tendsto_scaleR [OF tendsto_const]
  2019   Lim_neg ~> tendsto_minus
  2020   Lim_add ~> tendsto_add
  2021   Lim_sub ~> tendsto_diff
  2022   Lim_mul ~> tendsto_scaleR
  2023   Lim_vmul ~> tendsto_scaleR [OF _ tendsto_const]
  2024   Lim_null_norm ~> tendsto_norm_zero_iff [symmetric]
  2025   Lim_linear ~> bounded_linear.tendsto
  2026   Lim_component ~> tendsto_euclidean_component
  2027   Lim_component_cart ~> tendsto_vec_nth
  2028   Lim_inner ~> tendsto_inner [OF tendsto_const]
  2029   dot_lsum ~> inner_setsum_left
  2030   dot_rsum ~> inner_setsum_right
  2031   continuous_cmul ~> continuous_scaleR [OF continuous_const]
  2032   continuous_neg ~> continuous_minus
  2033   continuous_sub ~> continuous_diff
  2034   continuous_vmul ~> continuous_scaleR [OF _ continuous_const]
  2035   continuous_mul ~> continuous_scaleR
  2036   continuous_inv ~> continuous_inverse
  2037   continuous_at_within_inv ~> continuous_at_within_inverse
  2038   continuous_at_inv ~> continuous_at_inverse
  2039   continuous_at_norm ~> continuous_norm [OF continuous_at_id]
  2040   continuous_at_infnorm ~> continuous_infnorm [OF continuous_at_id]
  2041   continuous_at_component ~> continuous_component [OF continuous_at_id]
  2042   continuous_on_neg ~> continuous_on_minus
  2043   continuous_on_sub ~> continuous_on_diff
  2044   continuous_on_cmul ~> continuous_on_scaleR [OF continuous_on_const]
  2045   continuous_on_vmul ~> continuous_on_scaleR [OF _ continuous_on_const]
  2046   continuous_on_mul ~> continuous_on_scaleR
  2047   continuous_on_mul_real ~> continuous_on_mult
  2048   continuous_on_inner ~> continuous_on_inner [OF continuous_on_const]
  2049   continuous_on_norm ~> continuous_on_norm [OF continuous_on_id]
  2050   continuous_on_inverse ~> continuous_on_inv
  2051   uniformly_continuous_on_neg ~> uniformly_continuous_on_minus
  2052   uniformly_continuous_on_sub ~> uniformly_continuous_on_diff
  2053   subset_interior ~> interior_mono
  2054   subset_closure ~> closure_mono
  2055   closure_univ ~> closure_UNIV
  2056   real_arch_lt ~> reals_Archimedean2
  2057   real_arch ~> reals_Archimedean3
  2058   real_abs_norm ~> abs_norm_cancel
  2059   real_abs_sub_norm ~> norm_triangle_ineq3
  2060   norm_cauchy_schwarz_abs ~> Cauchy_Schwarz_ineq2
  2061 
  2062 * Session HOL-Probability:
  2063   - Caratheodory's extension lemma is now proved for ring_of_sets.
  2064   - Infinite products of probability measures are now available.
  2065   - Sigma closure is independent, if the generator is independent
  2066   - Use extended reals instead of positive extended
  2067     reals. INCOMPATIBILITY.
  2068 
  2069 * Session HOLCF: Discontinued legacy theorem names, INCOMPATIBILITY.
  2070 
  2071   expand_fun_below ~> fun_below_iff
  2072   below_fun_ext ~> fun_belowI
  2073   expand_cfun_eq ~> cfun_eq_iff
  2074   ext_cfun ~> cfun_eqI
  2075   expand_cfun_below ~> cfun_below_iff
  2076   below_cfun_ext ~> cfun_belowI
  2077   monofun_fun_fun ~> fun_belowD
  2078   monofun_fun_arg ~> monofunE
  2079   monofun_lub_fun ~> adm_monofun [THEN admD]
  2080   cont_lub_fun ~> adm_cont [THEN admD]
  2081   cont2cont_Rep_CFun ~> cont2cont_APP
  2082   cont_Rep_CFun_app ~> cont_APP_app
  2083   cont_Rep_CFun_app_app ~> cont_APP_app_app
  2084   cont_cfun_fun ~> cont_Rep_cfun1 [THEN contE]
  2085   cont_cfun_arg ~> cont_Rep_cfun2 [THEN contE]
  2086   contlub_cfun ~> lub_APP [symmetric]
  2087   contlub_LAM ~> lub_LAM [symmetric]
  2088   thelubI ~> lub_eqI
  2089   UU_I ~> bottomI
  2090   lift_distinct1 ~> lift.distinct(1)
  2091   lift_distinct2 ~> lift.distinct(2)
  2092   Def_not_UU ~> lift.distinct(2)
  2093   Def_inject ~> lift.inject
  2094   below_UU_iff ~> below_bottom_iff
  2095   eq_UU_iff ~> eq_bottom_iff
  2096 
  2097 
  2098 *** Document preparation ***
  2099 
  2100 * Antiquotation @{rail} layouts railroad syntax diagrams, see also
  2101 isar-ref manual, both for description and actual application of the
  2102 same.
  2103 
  2104 * Antiquotation @{value} evaluates the given term and presents its
  2105 result.
  2106 
  2107 * Antiquotations: term style "isub" provides ad-hoc conversion of
  2108 variables x1, y23 into subscripted form x\<^isub>1,
  2109 y\<^isub>2\<^isub>3.
  2110 
  2111 * Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
  2112 (e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).
  2113 
  2114 * Localized \isabellestyle switch can be used within blocks or groups
  2115 like this:
  2116 
  2117   \isabellestyle{it}  %preferred default
  2118   {\isabellestylett @{text "typewriter stuff"}}
  2119 
  2120 * Discontinued special treatment of hard tabulators.  Implicit
  2121 tab-width is now defined as 1.  Potential INCOMPATIBILITY for visual
  2122 layouts.
  2123 
  2124 
  2125 *** ML ***
  2126 
  2127 * The inner syntax of sort/type/term/prop supports inlined YXML
  2128 representations within quoted string tokens.  By encoding logical
  2129 entities via Term_XML (in ML or Scala) concrete syntax can be
  2130 bypassed, which is particularly useful for producing bits of text
  2131 under external program control.
  2132 
  2133 * Antiquotations for ML and document preparation are managed as theory
  2134 data, which requires explicit setup.
  2135 
  2136 * Isabelle_Process.is_active allows tools to check if the official
  2137 process wrapper is running (Isabelle/Scala/jEdit) or the old TTY loop
  2138 (better known as Proof General).
  2139 
  2140 * Structure Proof_Context follows standard naming scheme.  Old
  2141 ProofContext is still available for some time as legacy alias.
  2142 
  2143 * Structure Timing provides various operations for timing; supersedes
  2144 former start_timing/end_timing etc.
  2145 
  2146 * Path.print is the official way to show file-system paths to users
  2147 (including quotes etc.).
  2148 
  2149 * Inner syntax: identifiers in parse trees of generic categories
  2150 "logic", "aprop", "idt" etc. carry position information (disguised as
  2151 type constraints).  Occasional INCOMPATIBILITY with non-compliant
  2152 translations that choke on unexpected type constraints.  Positions can
  2153 be stripped in ML translations via Syntax.strip_positions /
  2154 Syntax.strip_positions_ast, or via the syntax constant
  2155 "_strip_positions" within parse trees.  As last resort, positions can
  2156 be disabled via the configuration option Syntax.positions, which is
  2157 called "syntax_positions" in Isar attribute syntax.
  2158 
  2159 * Discontinued special status of various ML structures that contribute
  2160 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
  2161 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
  2162 refer directly to Ast.Constant, Lexicon.is_identifier,
  2163 Syntax_Trans.mk_binder_tr etc.
  2164 
  2165 * Typed print translation: discontinued show_sorts argument, which is
  2166 already available via context of "advanced" translation.
  2167 
  2168 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
  2169 goal states; body tactic needs to address all subgoals uniformly.
  2170 
  2171 * Slightly more special eq_list/eq_set, with shortcut involving
  2172 pointer equality (assumes that eq relation is reflexive).
  2173 
  2174 * Classical tactics use proper Proof.context instead of historic types
  2175 claset/clasimpset.  Old-style declarations like addIs, addEs, addDs
  2176 operate directly on Proof.context.  Raw type claset retains its use as
  2177 snapshot of the classical context, which can be recovered via
  2178 (put_claset HOL_cs) etc.  Type clasimpset has been discontinued.
  2179 INCOMPATIBILITY, classical tactics and derived proof methods require
  2180 proper Proof.context.
  2181 
  2182 
  2183 *** System ***
  2184 
  2185 * Discontinued support for Poly/ML 5.2, which was the last version
  2186 without proper multithreading and TimeLimit implementation.
  2187 
  2188 * Discontinued old lib/scripts/polyml-platform, which has been
  2189 obsolete since Isabelle2009-2.
  2190 
  2191 * Various optional external tools are referenced more robustly and
  2192 uniformly by explicit Isabelle settings as follows:
  2193 
  2194   ISABELLE_CSDP   (formerly CSDP_EXE)
  2195   ISABELLE_GHC    (formerly EXEC_GHC or GHC_PATH)
  2196   ISABELLE_OCAML  (formerly EXEC_OCAML)
  2197   ISABELLE_SWIPL  (formerly EXEC_SWIPL)
  2198   ISABELLE_YAP    (formerly EXEC_YAP)
  2199 
  2200 Note that automated detection from the file-system or search path has
  2201 been discontinued.  INCOMPATIBILITY.
  2202 
  2203 * Scala layer provides JVM method invocation service for static
  2204 methods of type (String)String, see Invoke_Scala.method in ML.  For
  2205 example:
  2206 
  2207   Invoke_Scala.method "java.lang.System.getProperty" "java.home"
  2208 
  2209 Together with YXML.string_of_body/parse_body and XML.Encode/Decode
  2210 this allows to pass structured values between ML and Scala.
  2211 
  2212 * The IsabelleText fonts includes some further glyphs to support the
  2213 Prover IDE.  Potential INCOMPATIBILITY: users who happen to have
  2214 installed a local copy (which is normally *not* required) need to
  2215 delete or update it from ~~/lib/fonts/.
  2216 
  2217 
  2218 
  2219 New in Isabelle2011 (January 2011)
  2220 ----------------------------------
  2221 
  2222 *** General ***
  2223 
  2224 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
  2225 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
  2226 useful tooltips and hyperlinks produced from its static analysis.  The
  2227 bundled component provides an executable Isabelle tool that can be run
  2228 like this:
  2229 
  2230   Isabelle2011/bin/isabelle jedit
  2231 
  2232 * Significantly improved Isabelle/Isar implementation manual.
  2233 
  2234 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
  2235 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
  2236 while the default heap location within that directory lacks that extra
  2237 suffix.  This isolates multiple Isabelle installations from each
  2238 other, avoiding problems with old settings in new versions.
  2239 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
  2240 
  2241 * Source files are always encoded as UTF-8, instead of old-fashioned
  2242 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
  2243 the following package declarations:
  2244 
  2245   \usepackage[utf8]{inputenc}
  2246   \usepackage{textcomp}
  2247 
  2248 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
  2249 a Unicode character is treated as a single symbol, not a sequence of
  2250 non-ASCII bytes as before.  Since Isabelle/ML string literals may
  2251 contain symbols without further backslash escapes, Unicode can now be
  2252 used here as well.  Recall that Symbol.explode in ML provides a
  2253 consistent view on symbols, while raw explode (or String.explode)
  2254 merely give a byte-oriented representation.
  2255 
  2256 * Theory loader: source files are primarily located via the master
  2257 directory of each theory node (where the .thy file itself resides).
  2258 The global load path is still partially available as legacy feature.
  2259 Minor INCOMPATIBILITY due to subtle change in file lookup: use
  2260 explicit paths, relatively to the theory.
  2261 
  2262 * Special treatment of ML file names has been discontinued.
  2263 Historically, optional extensions .ML or .sml were added on demand --
  2264 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
  2265 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
  2266 
  2267 * Various options that affect pretty printing etc. are now properly
  2268 handled within the context via configuration options, instead of
  2269 unsynchronized references or print modes.  There are both ML Config.T
  2270 entities and Isar declaration attributes to access these.
  2271 
  2272   ML (Config.T)                 Isar (attribute)
  2273 
  2274   eta_contract                  eta_contract
  2275   show_brackets                 show_brackets
  2276   show_sorts                    show_sorts
  2277   show_types                    show_types
  2278   show_question_marks           show_question_marks
  2279   show_consts                   show_consts
  2280   show_abbrevs                  show_abbrevs
  2281 
  2282   Syntax.ast_trace              syntax_ast_trace
  2283   Syntax.ast_stat               syntax_ast_stat
  2284   Syntax.ambiguity_level        syntax_ambiguity_level
  2285 
  2286   Goal_Display.goals_limit      goals_limit
  2287   Goal_Display.show_main_goal   show_main_goal
  2288 
  2289   Method.rule_trace             rule_trace
  2290 
  2291   Thy_Output.display            thy_output_display
  2292   Thy_Output.quotes             thy_output_quotes
  2293   Thy_Output.indent             thy_output_indent
  2294   Thy_Output.source             thy_output_source
  2295   Thy_Output.break              thy_output_break
  2296 
  2297 Note that corresponding "..._default" references in ML may only be
  2298 changed globally at the ROOT session setup, but *not* within a theory.
  2299 The option "show_abbrevs" supersedes the former print mode
  2300 "no_abbrevs" with inverted meaning.
  2301 
  2302 * More systematic naming of some configuration options.
  2303 INCOMPATIBILITY.
  2304 
  2305   trace_simp  ~>  simp_trace
  2306   debug_simp  ~>  simp_debug
  2307 
  2308 * Support for real valued configuration options, using simplistic
  2309 floating-point notation that coincides with the inner syntax for
  2310 float_token.
  2311 
  2312 * Support for real valued preferences (with approximative PGIP type):
  2313 front-ends need to accept "pgint" values in float notation.
  2314 INCOMPATIBILITY.
  2315 
  2316 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
  2317 DejaVu Sans.
  2318 
  2319 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
  2320 
  2321 
  2322 *** Pure ***
  2323 
  2324 * Command 'type_synonym' (with single argument) replaces somewhat
  2325 outdated 'types', which is still available as legacy feature for some
  2326 time.
  2327 
  2328 * Command 'nonterminal' (with 'and' separated list of arguments)
  2329 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
  2330 
  2331 * Command 'notepad' replaces former 'example_proof' for
  2332 experimentation in Isar without any result.  INCOMPATIBILITY.
  2333 
  2334 * Locale interpretation commands 'interpret' and 'sublocale' accept
  2335 lists of equations to map definitions in a locale to appropriate
  2336 entities in the context of the interpretation.  The 'interpretation'
  2337 command already provided this functionality.
  2338 
  2339 * Diagnostic command 'print_dependencies' prints the locale instances
  2340 that would be activated if the specified expression was interpreted in
  2341 the current context.  Variant "print_dependencies!" assumes a context
  2342 without interpretations.
  2343 
  2344 * Diagnostic command 'print_interps' prints interpretations in proofs
  2345 in addition to interpretations in theories.
  2346 
  2347 * Discontinued obsolete 'global' and 'local' commands to manipulate
  2348 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
  2349 Sign.root_path and Sign.local_path may be applied directly where this
  2350 feature is still required for historical reasons.
  2351 
  2352 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
  2353 'definition' instead.
  2354 
  2355 * The "prems" fact, which refers to the accidental collection of
  2356 foundational premises in the context, is now explicitly marked as
  2357 legacy feature and will be discontinued soon.  Consider using "assms"
  2358 of the head statement or reference facts by explicit names.
  2359 
  2360 * Document antiquotations @{class} and @{type} print classes and type
  2361 constructors.
  2362 
  2363 * Document antiquotation @{file} checks file/directory entries within
  2364 the local file system.
  2365 
  2366 
  2367 *** HOL ***
  2368 
  2369 * Coercive subtyping: functions can be declared as coercions and type
  2370 inference will add them as necessary upon input of a term.  Theory
  2371 Complex_Main declares real :: nat => real and real :: int => real as
  2372 coercions. A coercion function f is declared like this:
  2373 
  2374   declare [[coercion f]]
  2375 
  2376 To lift coercions through type constructors (e.g. from nat => real to
  2377 nat list => real list), map functions can be declared, e.g.
  2378 
  2379   declare [[coercion_map map]]
  2380 
  2381 Currently coercion inference is activated only in theories including
  2382 real numbers, i.e. descendants of Complex_Main.  This is controlled by
  2383 the configuration option "coercion_enabled", e.g. it can be enabled in
  2384 other theories like this:
  2385 
  2386   declare [[coercion_enabled]]
  2387 
  2388 * Command 'partial_function' provides basic support for recursive
  2389 function definitions over complete partial orders.  Concrete instances
  2390 are provided for i) the option type, ii) tail recursion on arbitrary
  2391 types, and iii) the heap monad of Imperative_HOL.  See
  2392 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
  2393 for examples.
  2394 
  2395 * Function package: f.psimps rules are no longer implicitly declared
  2396 as [simp].  INCOMPATIBILITY.
  2397 
  2398 * Datatype package: theorems generated for executable equality (class
  2399 "eq") carry proper names and are treated as default code equations.
  2400 
  2401 * Inductive package: now offers command 'inductive_simps' to
  2402 automatically derive instantiated and simplified equations for
  2403 inductive predicates, similar to 'inductive_cases'.
  2404 
  2405 * Command 'enriched_type' allows to register properties of the
  2406 functorial structure of types.
  2407 
  2408 * Improved infrastructure for term evaluation using code generator
  2409 techniques, in particular static evaluation conversions.
  2410 
  2411 * Code generator: Scala (2.8 or higher) has been added to the target
  2412 languages.
  2413 
  2414 * Code generator: globbing constant expressions "*" and "Theory.*"
  2415 have been replaced by the more idiomatic "_" and "Theory._".
  2416 INCOMPATIBILITY.
  2417 
  2418 * Code generator: export_code without explicit file declaration prints
  2419 to standard output.  INCOMPATIBILITY.
  2420 
  2421 * Code generator: do not print function definitions for case
  2422 combinators any longer.
  2423 
  2424 * Code generator: simplification with rules determined with
  2425 src/Tools/Code/code_simp.ML and method "code_simp".
  2426 
  2427 * Code generator for records: more idiomatic representation of record
  2428 types.  Warning: records are not covered by ancient SML code
  2429 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
  2430 rep_datatype declaration helps to succeed then:
  2431 
  2432   record 'a foo = ...
  2433   ...
  2434   rep_datatype foo_ext ...
  2435 
  2436 * Records: logical foundation type for records does not carry a
  2437 '_type' suffix any longer (obsolete due to authentic syntax).
  2438 INCOMPATIBILITY.
  2439 
  2440 * Quickcheck now by default uses exhaustive testing instead of random
  2441 testing.  Random testing can be invoked by "quickcheck [random]",
  2442 exhaustive testing by "quickcheck [exhaustive]".
  2443 
  2444 * Quickcheck instantiates polymorphic types with small finite
  2445 datatypes by default. This enables a simple execution mechanism to
  2446 handle quantifiers and function equality over the finite datatypes.
  2447 
  2448 * Quickcheck random generator has been renamed from "code" to
  2449 "random".  INCOMPATIBILITY.
  2450 
  2451 * Quickcheck now has a configurable time limit which is set to 30
  2452 seconds by default. This can be changed by adding [timeout = n] to the
  2453 quickcheck command. The time limit for Auto Quickcheck is still set
  2454 independently.
  2455 
  2456 * Quickcheck in locales considers interpretations of that locale for
  2457 counter example search.
  2458 
  2459 * Sledgehammer:
  2460   - Added "smt" and "remote_smt" provers based on the "smt" proof
  2461     method. See the Sledgehammer manual for details ("isabelle doc
  2462     sledgehammer").
  2463   - Renamed commands:
  2464     sledgehammer atp_info ~> sledgehammer running_provers
  2465     sledgehammer atp_kill ~> sledgehammer kill_provers
  2466     sledgehammer available_atps ~> sledgehammer available_provers
  2467     INCOMPATIBILITY.
  2468   - Renamed options:
  2469     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
  2470     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
  2471     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
  2472     (and "ms" and "min" are no longer supported)
  2473     INCOMPATIBILITY.
  2474 
  2475 * Nitpick:
  2476   - Renamed options:
  2477     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
  2478     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
  2479     INCOMPATIBILITY.
  2480   - Added support for partial quotient types.
  2481   - Added local versions of the "Nitpick.register_xxx" functions.
  2482   - Added "whack" option.
  2483   - Allow registration of quotient types as codatatypes.
  2484   - Improved "merge_type_vars" option to merge more types.
  2485   - Removed unsound "fast_descrs" option.
  2486   - Added custom symmetry breaking for datatypes, making it possible to reach
  2487     higher cardinalities.
  2488   - Prevent the expansion of too large definitions.
  2489 
  2490 * Proof methods "metis" and "meson" now have configuration options
  2491 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
  2492 to diagnose these tools. E.g.
  2493 
  2494     using [[metis_trace = true]]
  2495 
  2496 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
  2497 manually as command 'solve_direct'.
  2498 
  2499 * The default SMT solver Z3 must be enabled explicitly (due to
  2500 licensing issues) by setting the environment variable
  2501 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
  2502 commercial applications, the SMT solver CVC3 is provided as fall-back;
  2503 changing the SMT solver is done via the configuration option
  2504 "smt_solver".
  2505 
  2506 * Remote SMT solvers need to be referred to by the "remote_" prefix,
  2507 i.e. "remote_cvc3" and "remote_z3".
  2508 
  2509 * Added basic SMT support for datatypes, records, and typedefs using
  2510 the oracle mode (no proofs).  Direct support of pairs has been dropped
  2511 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
  2512 support for a similar behavior).  Minor INCOMPATIBILITY.
  2513 
  2514 * Changed SMT configuration options:
  2515   - Renamed:
  2516     z3_proofs ~> smt_oracle (with inverted meaning)
  2517     z3_trace_assms ~> smt_trace_used_facts
  2518     INCOMPATIBILITY.
  2519   - Added:
  2520     smt_verbose
  2521     smt_random_seed
  2522     smt_datatypes
  2523     smt_infer_triggers
  2524     smt_monomorph_limit
  2525     cvc3_options
  2526     remote_cvc3_options
  2527     remote_z3_options
  2528     yices_options
  2529 
  2530 * Boogie output files (.b2i files) need to be declared in the theory
  2531 header.
  2532 
  2533 * Simplification procedure "list_to_set_comprehension" rewrites list
  2534 comprehensions applied to List.set to set comprehensions.  Occasional
  2535 INCOMPATIBILITY, may be deactivated like this:
  2536 
  2537   declare [[simproc del: list_to_set_comprehension]]
  2538 
  2539 * Removed old version of primrec package.  INCOMPATIBILITY.
  2540 
  2541 * Removed simplifier congruence rule of "prod_case", as has for long
  2542 been the case with "split".  INCOMPATIBILITY.
  2543 
  2544 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
  2545 
  2546 * Removed [split_format ... and ... and ...] version of
  2547 [split_format].  Potential INCOMPATIBILITY.
  2548 
  2549 * Predicate "sorted" now defined inductively, with nice induction
  2550 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
  2551 
  2552 * Constant "contents" renamed to "the_elem", to free the generic name
  2553 contents for other uses.  INCOMPATIBILITY.
  2554 
  2555 * Renamed class eq and constant eq (for code generation) to class
  2556 equal and constant equal, plus renaming of related facts and various
  2557 tuning.  INCOMPATIBILITY.
  2558 
  2559 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
  2560 
  2561 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
  2562 INCOMPATIBILITY.
  2563 
  2564 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
  2565 avoid confusion with finite sets.  INCOMPATIBILITY.
  2566 
  2567 * Abandoned locales equiv, congruent and congruent2 for equivalence
  2568 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
  2569 for congruent(2)).
  2570 
  2571 * Some previously unqualified names have been qualified:
  2572 
  2573   types
  2574     bool ~> HOL.bool
  2575     nat ~> Nat.nat
  2576 
  2577   constants
  2578     Trueprop ~> HOL.Trueprop
  2579     True ~> HOL.True
  2580     False ~> HOL.False
  2581     op & ~> HOL.conj
  2582     op | ~> HOL.disj
  2583     op --> ~> HOL.implies
  2584     op = ~> HOL.eq
  2585     Not ~> HOL.Not
  2586     The ~> HOL.The
  2587     All ~> HOL.All
  2588     Ex ~> HOL.Ex
  2589     Ex1 ~> HOL.Ex1
  2590     Let ~> HOL.Let
  2591     If ~> HOL.If
  2592     Ball ~> Set.Ball
  2593     Bex ~> Set.Bex
  2594     Suc ~> Nat.Suc
  2595     Pair ~> Product_Type.Pair
  2596     fst ~> Product_Type.fst
  2597     snd ~> Product_Type.snd
  2598     curry ~> Product_Type.curry
  2599     op : ~> Set.member
  2600     Collect ~> Set.Collect
  2601 
  2602 INCOMPATIBILITY.
  2603 
  2604 * More canonical naming convention for some fundamental definitions:
  2605 
  2606     bot_bool_eq ~> bot_bool_def
  2607     top_bool_eq ~> top_bool_def
  2608     inf_bool_eq ~> inf_bool_def
  2609     sup_bool_eq ~> sup_bool_def
  2610     bot_fun_eq  ~> bot_fun_def
  2611     top_fun_eq  ~> top_fun_def
  2612     inf_fun_eq  ~> inf_fun_def
  2613     sup_fun_eq  ~> sup_fun_def
  2614 
  2615 INCOMPATIBILITY.
  2616 
  2617 * More stylized fact names:
  2618 
  2619   expand_fun_eq ~> fun_eq_iff
  2620   expand_set_eq ~> set_eq_iff
  2621   set_ext       ~> set_eqI
  2622   nat_number    ~> eval_nat_numeral
  2623 
  2624 INCOMPATIBILITY.
  2625 
  2626 * Refactoring of code-generation specific operations in theory List:
  2627 
  2628   constants
  2629     null ~> List.null
  2630 
  2631   facts
  2632     mem_iff ~> member_def
  2633     null_empty ~> null_def
  2634 
  2635 INCOMPATIBILITY.  Note that these were not supposed to be used
  2636 regularly unless for striking reasons; their main purpose was code
  2637 generation.
  2638 
  2639 Various operations from the Haskell prelude are used for generating
  2640 Haskell code.
  2641 
  2642 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
  2643 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
  2644 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
  2645 
  2646 * Abolished some non-alphabetic type names: "prod" and "sum" replace
  2647 "*" and "+" respectively.  INCOMPATIBILITY.
  2648 
  2649 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
  2650 "Sum_Type.Plus" instead.
  2651 
  2652 * Constant "split" has been merged with constant "prod_case"; names of
  2653 ML functions, facts etc. involving split have been retained so far,
  2654 though.  INCOMPATIBILITY.
  2655 
  2656 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
  2657 instead.  INCOMPATIBILITY.
  2658 
  2659 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
  2660 INCOMPATIBILITY.
  2661 
  2662 * Former theory Library/Enum is now part of the HOL-Main image.
  2663 INCOMPATIBILITY: all constants of the Enum theory now have to be
  2664 referred to by its qualified name.
  2665 
  2666   enum    ~>  Enum.enum
  2667   nlists  ~>  Enum.nlists
  2668   product ~>  Enum.product
  2669 
  2670 * Theory Library/Monad_Syntax provides do-syntax for monad types.
  2671 Syntax in Library/State_Monad has been changed to avoid ambiguities.
  2672 INCOMPATIBILITY.
  2673 
  2674 * Theory Library/SetsAndFunctions has been split into
  2675 Library/Function_Algebras and Library/Set_Algebras; canonical names
  2676 for instance definitions for functions; various improvements.
  2677 INCOMPATIBILITY.
  2678 
  2679 * Theory Library/Multiset provides stable quicksort implementation of
  2680 sort_key.
  2681 
  2682 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
  2683 INCOMPATIBILITY.
  2684 
  2685 * Session Multivariate_Analysis: introduced a type class for euclidean
  2686 space.  Most theorems are now stated in terms of euclidean spaces
  2687 instead of finite cartesian products.
  2688 
  2689   types
  2690     real ^ 'n ~>  'a::real_vector
  2691               ~>  'a::euclidean_space
  2692               ~>  'a::ordered_euclidean_space
  2693         (depends on your needs)
  2694 
  2695   constants
  2696      _ $ _        ~> _ $$ _
  2697      \<chi> x. _  ~> \<chi>\<chi> x. _
  2698      CARD('n)     ~> DIM('a)
  2699 
  2700 Also note that the indices are now natural numbers and not from some
  2701 finite type. Finite cartesian products of euclidean spaces, products
  2702 of euclidean spaces the real and complex numbers are instantiated to
  2703 be euclidean_spaces.  INCOMPATIBILITY.
  2704 
  2705 * Session Probability: introduced pextreal as positive extended real
  2706 numbers.  Use pextreal as value for measures.  Introduce the
  2707 Radon-Nikodym derivative, product spaces and Fubini's theorem for
  2708 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
  2709 the integral in Multivariate Analysis.  INCOMPATIBILITY.
  2710 
  2711 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
  2712 INCOMPATIBILITY.
  2713 
  2714 * Session SPARK (with image HOL-SPARK) provides commands to load and
  2715 prove verification conditions generated by the SPARK Ada program
  2716 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
  2717 
  2718 
  2719 *** HOL-Algebra ***
  2720 
  2721 * Theorems for additive ring operations (locale abelian_monoid and
  2722 descendants) are generated by interpretation from their multiplicative
  2723 counterparts.  Names (in particular theorem names) have the mandatory
  2724 qualifier 'add'.  Previous theorem names are redeclared for
  2725 compatibility.
  2726 
  2727 * Structure "int_ring" is now an abbreviation (previously a
  2728 definition).  This fits more natural with advanced interpretations.
  2729 
  2730 
  2731 *** HOLCF ***
  2732 
  2733 * The domain package now runs in definitional mode by default: The
  2734 former command 'new_domain' is now called 'domain'.  To use the domain
  2735 package in its original axiomatic mode, use 'domain (unsafe)'.
  2736 INCOMPATIBILITY.
  2737 
  2738 * The new class "domain" is now the default sort.  Class "predomain"
  2739 is an unpointed version of "domain". Theories can be updated by
  2740 replacing sort annotations as shown below.  INCOMPATIBILITY.
  2741 
  2742   'a::type ~> 'a::countable
  2743   'a::cpo  ~> 'a::predomain
  2744   'a::pcpo ~> 'a::domain
  2745 
  2746 * The old type class "rep" has been superseded by class "domain".
  2747 Accordingly, users of the definitional package must remove any
  2748 "default_sort rep" declarations.  INCOMPATIBILITY.
  2749 
  2750 * The domain package (definitional mode) now supports unpointed
  2751 predomain argument types, as long as they are marked 'lazy'. (Strict
  2752 arguments must be in class "domain".) For example, the following
  2753 domain definition now works:
  2754 
  2755   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
  2756 
  2757 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
  2758 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
  2759 'a option, and 'a list.  Additionally, it configures fixrec and the
  2760 domain package to work with these types.  For example:
  2761 
  2762   fixrec isInl :: "('a + 'b) u -> tr"
  2763     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
  2764 
  2765   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
  2766 
  2767 * The "(permissive)" option of fixrec has been replaced with a
  2768 per-equation "(unchecked)" option. See
  2769 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
  2770 
  2771 * The "bifinite" class no longer fixes a constant "approx"; the class
  2772 now just asserts that such a function exists.  INCOMPATIBILITY.
  2773 
  2774 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
  2775 defines an embedding of type 'a defl into udom by default; instances
  2776 of "bifinite" and "domain" classes are available in
  2777 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
  2778 
  2779 * The syntax "REP('a)" has been replaced with "DEFL('a)".
  2780 
  2781 * The predicate "directed" has been removed.  INCOMPATIBILITY.
  2782 
  2783 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
  2784 
  2785 * The function "cprod_map" has been renamed to "prod_map".
  2786 INCOMPATIBILITY.
  2787 
  2788 * The monadic bind operator on each powerdomain has new binder syntax
  2789 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
  2790 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
  2791 
  2792 * The infix syntax for binary union on each powerdomain has changed
  2793 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
  2794 syntax.  INCOMPATIBILITY.
  2795 
  2796 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
  2797 still supported as an input translation.
  2798 
  2799 * Renamed some theorems (the original names are also still available).
  2800 
  2801   expand_fun_below   ~> fun_below_iff
  2802   below_fun_ext      ~> fun_belowI
  2803   expand_cfun_eq     ~> cfun_eq_iff
  2804   ext_cfun           ~> cfun_eqI
  2805   expand_cfun_below  ~> cfun_below_iff
  2806   below_cfun_ext     ~> cfun_belowI
  2807   cont2cont_Rep_CFun ~> cont2cont_APP
  2808 
  2809 * The Abs and Rep functions for various types have changed names.
  2810 Related theorem names have also changed to match. INCOMPATIBILITY.
  2811 
  2812   Rep_CFun  ~> Rep_cfun
  2813   Abs_CFun  ~> Abs_cfun
  2814   Rep_Sprod ~> Rep_sprod
  2815   Abs_Sprod ~> Abs_sprod
  2816   Rep_Ssum  ~> Rep_ssum
  2817   Abs_Ssum  ~> Abs_ssum
  2818 
  2819 * Lemmas with names of the form *_defined_iff or *_strict_iff have
  2820 been renamed to *_bottom_iff.  INCOMPATIBILITY.
  2821 
  2822 * Various changes to bisimulation/coinduction with domain package:
  2823 
  2824   - Definitions of "bisim" constants no longer mention definedness.
  2825   - With mutual recursion, "bisim" predicate is now curried.
  2826   - With mutual recursion, each type gets a separate coind theorem.
  2827   - Variable names in bisim_def and coinduct rules have changed.
  2828 
  2829 INCOMPATIBILITY.
  2830 
  2831 * Case combinators generated by the domain package for type "foo" are
  2832 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
  2833 
  2834 * Several theorems have been renamed to more accurately reflect the
  2835 names of constants and types involved.  INCOMPATIBILITY.
  2836 
  2837   thelub_const    ~> lub_const
  2838   lub_const       ~> is_lub_const
  2839   thelubI         ~> lub_eqI
  2840   is_lub_lub      ~> is_lubD2
  2841   lubI            ~> is_lub_lub
  2842   unique_lub      ~> is_lub_unique
  2843   is_ub_lub       ~> is_lub_rangeD1
  2844   lub_bin_chain   ~> is_lub_bin_chain
  2845   lub_fun         ~> is_lub_fun
  2846   thelub_fun      ~> lub_fun
  2847   thelub_cfun     ~> lub_cfun
  2848   thelub_Pair     ~> lub_Pair
  2849   lub_cprod       ~> is_lub_prod
  2850   thelub_cprod    ~> lub_prod
  2851   minimal_cprod   ~> minimal_prod
  2852   inst_cprod_pcpo ~> inst_prod_pcpo
  2853   UU_I            ~> bottomI
  2854   compact_UU      ~> compact_bottom
  2855   deflation_UU    ~> deflation_bottom
  2856   finite_deflation_UU ~> finite_deflation_bottom
  2857 
  2858 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
  2859 
  2860   sq_ord_less_eq_trans ~> below_eq_trans
  2861   sq_ord_eq_less_trans ~> eq_below_trans
  2862   refl_less            ~> below_refl
  2863   trans_less           ~> below_trans
  2864   antisym_less         ~> below_antisym
  2865   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
  2866   box_less             ~> box_below
  2867   rev_trans_less       ~> rev_below_trans
  2868   not_less2not_eq      ~> not_below2not_eq
  2869   less_UU_iff          ~> below_UU_iff
  2870   flat_less_iff        ~> flat_below_iff
  2871   adm_less             ~> adm_below
  2872   adm_not_less         ~> adm_not_below
  2873   adm_compact_not_less ~> adm_compact_not_below
  2874   less_fun_def         ~> below_fun_def
  2875   expand_fun_less      ~> fun_below_iff
  2876   less_fun_ext         ~> fun_belowI
  2877   less_discr_def       ~> below_discr_def
  2878   discr_less_eq        ~> discr_below_eq
  2879   less_unit_def        ~> below_unit_def
  2880   less_cprod_def       ~> below_prod_def
  2881   prod_lessI           ~> prod_belowI
  2882   Pair_less_iff        ~> Pair_below_iff
  2883   fst_less_iff         ~> fst_below_iff
  2884   snd_less_iff         ~> snd_below_iff
  2885   expand_cfun_less     ~> cfun_below_iff
  2886   less_cfun_ext        ~> cfun_belowI
  2887   injection_less       ~> injection_below
  2888   less_up_def          ~> below_up_def
  2889   not_Iup_less         ~> not_Iup_below
  2890   Iup_less             ~> Iup_below
  2891   up_less              ~> up_below
  2892   Def_inject_less_eq   ~> Def_below_Def
  2893   Def_less_is_eq       ~> Def_below_iff
  2894   spair_less_iff       ~> spair_below_iff
  2895   less_sprod           ~> below_sprod
  2896   spair_less           ~> spair_below
  2897   sfst_less_iff        ~> sfst_below_iff
  2898   ssnd_less_iff        ~> ssnd_below_iff
  2899   fix_least_less       ~> fix_least_below
  2900   dist_less_one        ~> dist_below_one
  2901   less_ONE             ~> below_ONE
  2902   ONE_less_iff         ~> ONE_below_iff
  2903   less_sinlD           ~> below_sinlD
  2904   less_sinrD           ~> below_sinrD
  2905 
  2906 
  2907 *** FOL and ZF ***
  2908 
  2909 * All constant names are now qualified internally and use proper
  2910 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
  2911 
  2912 
  2913 *** ML ***
  2914 
  2915 * Antiquotation @{assert} inlines a function bool -> unit that raises
  2916 Fail if the argument is false.  Due to inlining the source position of
  2917 failed assertions is included in the error output.
  2918 
  2919 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
  2920 text is in practice always evaluated with a stable theory checkpoint.
  2921 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
  2922 
  2923 * Antiquotation @{theory A} refers to theory A from the ancestry of
  2924 the current context, not any accidental theory loader state as before.
  2925 Potential INCOMPATIBILITY, subtle change in semantics.
  2926 
  2927 * Syntax.pretty_priority (default 0) configures the required priority
  2928 of pretty-printed output and thus affects insertion of parentheses.
  2929 
  2930 * Syntax.default_root (default "any") configures the inner syntax
  2931 category (nonterminal symbol) for parsing of terms.
  2932 
  2933 * Former exception Library.UnequalLengths now coincides with
  2934 ListPair.UnequalLengths.
  2935 
  2936 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
  2937 main functionality is provided by structure Simplifier.
  2938 
  2939 * Renamed raw "explode" function to "raw_explode" to emphasize its
  2940 meaning.  Note that internally to Isabelle, Symbol.explode is used in
  2941 almost all situations.
  2942 
  2943 * Discontinued obsolete function sys_error and exception SYS_ERROR.
  2944 See implementation manual for further details on exceptions in
  2945 Isabelle/ML.
  2946 
  2947 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
  2948 meaning.
  2949 
  2950 * Renamed structure PureThy to Pure_Thy and moved most of its
  2951 operations to structure Global_Theory, to emphasize that this is
  2952 rarely-used global-only stuff.
  2953 
  2954 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
  2955 instead (or tracing for high-volume output).
  2956 
  2957 * Configuration option show_question_marks only affects regular pretty
  2958 printing of types and terms, not raw Term.string_of_vname.
  2959 
  2960 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
  2961 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
  2962 @{thms} for most purposes.
  2963 
  2964 * ML structure Unsynchronized is never opened, not even in Isar
  2965 interaction mode as before.  Old Unsynchronized.set etc. have been
  2966 discontinued -- use plain := instead.  This should be *rare* anyway,
  2967 since modern tools always work via official context data, notably
  2968 configuration options.
  2969 
  2970 * Parallel and asynchronous execution requires special care concerning
  2971 interrupts.  Structure Exn provides some convenience functions that
  2972 avoid working directly with raw Interrupt.  User code must not absorb
  2973 interrupts -- intermediate handling (for cleanup etc.) needs to be
  2974 followed by re-raising of the original exception.  Another common
  2975 source of mistakes are "handle _" patterns, which make the meaning of
  2976 the program subject to physical effects of the environment.
  2977 
  2978 
  2979 
  2980 New in Isabelle2009-2 (June 2010)
  2981 ---------------------------------
  2982 
  2983 *** General ***
  2984 
  2985 * Authentic syntax for *all* logical entities (type classes, type
  2986 constructors, term constants): provides simple and robust
  2987 correspondence between formal entities and concrete syntax.  Within
  2988 the parse tree / AST representations, "constants" are decorated by
  2989 their category (class, type, const) and spelled out explicitly with
  2990 their full internal name.
  2991 
  2992 Substantial INCOMPATIBILITY concerning low-level syntax declarations
  2993 and translations (translation rules and translation functions in ML).
  2994 Some hints on upgrading:
  2995 
  2996   - Many existing uses of 'syntax' and 'translations' can be replaced
  2997     by more modern 'type_notation', 'notation' and 'abbreviation',
  2998     which are independent of this issue.
  2999 
  3000   - 'translations' require markup within the AST; the term syntax
  3001     provides the following special forms:
  3002 
  3003       CONST c   -- produces syntax version of constant c from context
  3004       XCONST c  -- literally c, checked as constant from context
  3005       c         -- literally c, if declared by 'syntax'
  3006 
  3007     Plain identifiers are treated as AST variables -- occasionally the
  3008     system indicates accidental variables via the error "rhs contains
  3009     extra variables".
  3010 
  3011     Type classes and type constructors are marked according to their
  3012     concrete syntax.  Some old translations rules need to be written
  3013     for the "type" category, using type constructor application
  3014     instead of pseudo-term application of the default category
  3015     "logic".
  3016 
  3017   - 'parse_translation' etc. in ML may use the following
  3018     antiquotations:
  3019 
  3020       @{class_syntax c}   -- type class c within parse tree / AST
  3021       @{term_syntax c}    -- type constructor c within parse tree / AST
  3022       @{const_syntax c}   -- ML version of "CONST c" above
  3023       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
  3024 
  3025   - Literal types within 'typed_print_translations', i.e. those *not*
  3026     represented as pseudo-terms are represented verbatim.  Use @{class
  3027     c} or @{type_name c} here instead of the above syntax
  3028     antiquotations.
  3029 
  3030 Note that old non-authentic syntax was based on unqualified base
  3031 names, so all of the above "constant" names would coincide.  Recall
  3032 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
  3033 diagnose syntax problems.
  3034 
  3035 * Type constructors admit general mixfix syntax, not just infix.
  3036 
  3037 * Concrete syntax may be attached to local entities without a proof
  3038 body, too.  This works via regular mixfix annotations for 'fix',
  3039 'def', 'obtain' etc. or via the explicit 'write' command, which is
  3040 similar to the 'notation' command in theory specifications.
  3041 
  3042 * Discontinued unnamed infix syntax (legacy feature for many years) --
  3043 need to specify constant name and syntax separately.  Internal ML
  3044 datatype constructors have been renamed from InfixName to Infix etc.
  3045 Minor INCOMPATIBILITY.
  3046 
  3047 * Schematic theorem statements need to be explicitly markup as such,
  3048 via commands 'schematic_lemma', 'schematic_theorem',
  3049 'schematic_corollary'.  Thus the relevance of the proof is made
  3050 syntactically clear, which impacts performance in a parallel or
  3051 asynchronous interactive environment.  Minor INCOMPATIBILITY.
  3052 
  3053 * Use of cumulative prems via "!" in some proof methods has been
  3054 discontinued (old legacy feature).
  3055 
  3056 * References 'trace_simp' and 'debug_simp' have been replaced by
  3057 configuration options stored in the context. Enabling tracing (the
  3058 case of debugging is similar) in proofs works via
  3059 
  3060   using [[trace_simp = true]]
  3061 
  3062 Tracing is then active for all invocations of the simplifier in
  3063 subsequent goal refinement steps. Tracing may also still be enabled or
  3064 disabled via the ProofGeneral settings menu.
  3065 
  3066 * Separate commands 'hide_class', 'hide_type', 'hide_const',
  3067 'hide_fact' replace the former 'hide' KIND command.  Minor
  3068 INCOMPATIBILITY.
  3069 
  3070 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
  3071 more efficient than combinations with -q1 or -q2.
  3072 
  3073 
  3074 *** Pure ***
  3075 
  3076 * Proofterms record type-class reasoning explicitly, using the
  3077 "unconstrain" operation internally.  This eliminates all sort
  3078 constraints from a theorem and proof, introducing explicit
  3079 OFCLASS-premises.  On the proof term level, this operation is
  3080 automatically applied at theorem boundaries, such that closed proofs
  3081 are always free of sort constraints.  INCOMPATIBILITY for tools that
  3082 inspect proof terms.
  3083 
  3084 * Local theory specifications may depend on extra type variables that
  3085 are not present in the result type -- arguments TYPE('a) :: 'a itself
  3086 are added internally.  For example:
  3087 
  3088   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
  3089 
  3090 * Predicates of locales introduced by classes carry a mandatory
  3091 "class" prefix.  INCOMPATIBILITY.
  3092 
  3093 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
  3094 
  3095 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
  3096 'class' instead.
  3097 
  3098 * Command 'code_reflect' allows to incorporate generated ML code into
  3099 runtime environment; replaces immature code_datatype antiquotation.
  3100 INCOMPATIBILITY.
  3101 
  3102 * Code generator: simple concept for abstract datatypes obeying
  3103 invariants.
  3104 
  3105 * Code generator: details of internal data cache have no impact on the
  3106 user space functionality any longer.
  3107 
  3108 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  3109 subgoals.  This is more appropriate for interpretations with 'where'.
  3110 INCOMPATIBILITY.
  3111 
  3112 * Command 'example_proof' opens an empty proof body.  This allows to
  3113 experiment with Isar, without producing any persistent result.
  3114 
  3115 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  3116 within a local theory context, with explicit checking of the
  3117 constructors involved (in contrast to the raw 'syntax' versions).
  3118 
  3119 * Commands 'types' and 'typedecl' now work within a local theory
  3120 context -- without introducing dependencies on parameters or
  3121 assumptions, which is not possible in Isabelle/Pure.
  3122 
  3123 * Command 'defaultsort' has been renamed to 'default_sort', it works
  3124 within a local theory context.  Minor INCOMPATIBILITY.
  3125 
  3126 
  3127 *** HOL ***
  3128 
  3129 * Command 'typedef' now works within a local theory context -- without
  3130 introducing dependencies on parameters or assumptions, which is not
  3131 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  3132 contain multiple interpretations of local typedefs (with different
  3133 non-emptiness proofs), even in a global theory context.
  3134 
  3135 * New package for quotient types.  Commands 'quotient_type' and
  3136 'quotient_definition' may be used for defining types and constants by
  3137 quotient constructions.  An example is the type of integers created by
  3138 quotienting pairs of natural numbers:
  3139 
  3140   fun
  3141     intrel :: "(nat * nat) => (nat * nat) => bool"
  3142   where
  3143     "intrel (x, y) (u, v) = (x + v = u + y)"
  3144 
  3145   quotient_type int = "nat * nat" / intrel
  3146     by (auto simp add: equivp_def expand_fun_eq)
  3147 
  3148   quotient_definition
  3149     "0::int" is "(0::nat, 0::nat)"
  3150 
  3151 The method "lifting" can be used to lift of theorems from the
  3152 underlying "raw" type to the quotient type.  The example
  3153 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  3154 construction and provides a reasoning infrastructure for finite sets.
  3155 
  3156 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  3157 clash with new theory Quotient in Main HOL.
  3158 
  3159 * Moved the SMT binding into the main HOL session, eliminating
  3160 separate HOL-SMT session.
  3161 
  3162 * List membership infix mem operation is only an input abbreviation.
  3163 INCOMPATIBILITY.
  3164 
  3165 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  3166 for future developements; former Library/Word.thy is still present in
  3167 the AFP entry RSAPPS.
  3168 
  3169 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  3170 longer shadowed.  INCOMPATIBILITY.
  3171 
  3172 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  3173 INCOMPATIBILITY.
  3174 
  3175 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  3176 INCOMPATIBILITY.
  3177 
  3178 * Dropped normalizing_semiring etc; use the facts in semiring classes
  3179 instead.  INCOMPATIBILITY.
  3180 
  3181 * Dropped several real-specific versions of lemmas about floor and
  3182 ceiling; use the generic lemmas from theory "Archimedean_Field"
  3183 instead.  INCOMPATIBILITY.
  3184 
  3185   floor_number_of_eq         ~> floor_number_of
  3186   le_floor_eq_number_of      ~> number_of_le_floor
  3187   le_floor_eq_zero           ~> zero_le_floor
  3188   le_floor_eq_one            ~> one_le_floor
  3189   floor_less_eq_number_of    ~> floor_less_number_of
  3190   floor_less_eq_zero         ~> floor_less_zero
  3191   floor_less_eq_one          ~> floor_less_one
  3192   less_floor_eq_number_of    ~> number_of_less_floor
  3193   less_floor_eq_zero         ~> zero_less_floor
  3194   less_floor_eq_one          ~> one_less_floor
  3195   floor_le_eq_number_of      ~> floor_le_number_of
  3196   floor_le_eq_zero           ~> floor_le_zero
  3197   floor_le_eq_one            ~> floor_le_one
  3198   floor_subtract_number_of   ~> floor_diff_number_of
  3199   floor_subtract_one         ~> floor_diff_one
  3200   ceiling_number_of_eq       ~> ceiling_number_of
  3201   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  3202   ceiling_le_zero_eq         ~> ceiling_le_zero
  3203   ceiling_le_eq_one          ~> ceiling_le_one
  3204   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  3205   less_ceiling_eq_zero       ~> zero_less_ceiling
  3206   less_ceiling_eq_one        ~> one_less_ceiling
  3207   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  3208   ceiling_less_eq_zero       ~> ceiling_less_zero
  3209   ceiling_less_eq_one        ~> ceiling_less_one
  3210   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  3211   le_ceiling_eq_zero         ~> zero_le_ceiling
  3212   le_ceiling_eq_one          ~> one_le_ceiling
  3213   ceiling_subtract_number_of ~> ceiling_diff_number_of
  3214   ceiling_subtract_one       ~> ceiling_diff_one
  3215 
  3216 * Theory "Finite_Set": various folding_XXX locales facilitate the
  3217 application of the various fold combinators on finite sets.
  3218 
  3219 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  3220 provides abstract red-black tree type which is backed by "RBT_Impl" as
  3221 implementation.  INCOMPATIBILTY.
  3222 
  3223 * Theory Library/Coinductive_List has been removed -- superseded by
  3224 AFP/thys/Coinductive.
  3225 
  3226 * Theory PReal, including the type "preal" and related operations, has
  3227 been removed.  INCOMPATIBILITY.
  3228 
  3229 * Real: new development using Cauchy Sequences.
  3230 
  3231 * Split off theory "Big_Operators" containing setsum, setprod,
  3232 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  3233 
  3234 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  3235 "Int" etc.  INCOMPATIBILITY.
  3236 
  3237 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  3238 
  3239 * New set of rules "ac_simps" provides combined assoc / commute
  3240 rewrites for all interpretations of the appropriate generic locales.
  3241 
  3242 * Renamed theory "OrderedGroup" to "Groups" and split theory
  3243 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  3244 appropriate and more consistent names suitable for name prefixes
  3245 within the HOL theories.  INCOMPATIBILITY.
  3246 
  3247 * Some generic constants have been put to appropriate theories:
  3248   - less_eq, less: Orderings
  3249   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  3250   - inverse, divide: Rings
  3251 INCOMPATIBILITY.
  3252 
  3253 * More consistent naming of type classes involving orderings (and
  3254 lattices):
  3255 
  3256     lower_semilattice                   ~> semilattice_inf
  3257     upper_semilattice                   ~> semilattice_sup
  3258 
  3259     dense_linear_order                  ~> dense_linorder
  3260 
  3261     pordered_ab_group_add               ~> ordered_ab_group_add
  3262     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  3263     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  3264     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  3265     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  3266     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  3267     pordered_cancel_semiring            ~> ordered_cancel_semiring
  3268     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  3269     pordered_comm_ring                  ~> ordered_comm_ring
  3270     pordered_comm_semiring              ~> ordered_comm_semiring
  3271     pordered_ring                       ~> ordered_ring
  3272     pordered_ring_abs                   ~> ordered_ring_abs
  3273     pordered_semiring                   ~> ordered_semiring
  3274 
  3275     ordered_ab_group_add                ~> linordered_ab_group_add
  3276     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  3277     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  3278     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  3279     ordered_field                       ~> linordered_field
  3280     ordered_field_no_lb                 ~> linordered_field_no_lb
  3281     ordered_field_no_ub                 ~> linordered_field_no_ub
  3282     ordered_field_dense_linear_order    ~> dense_linordered_field
  3283     ordered_idom                        ~> linordered_idom
  3284     ordered_ring                        ~> linordered_ring
  3285     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  3286     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  3287     ordered_ring_strict                 ~> linordered_ring_strict
  3288     ordered_semidom                     ~> linordered_semidom
  3289     ordered_semiring                    ~> linordered_semiring
  3290     ordered_semiring_1                  ~> linordered_semiring_1
  3291     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  3292     ordered_semiring_strict             ~> linordered_semiring_strict
  3293 
  3294   The following slightly odd type classes have been moved to a
  3295   separate theory Library/Lattice_Algebras:
  3296 
  3297     lordered_ab_group_add               ~> lattice_ab_group_add
  3298     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  3299     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  3300     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  3301     lordered_ring                       ~> lattice_ring
  3302 
  3303 INCOMPATIBILITY.
  3304 
  3305 * Refined field classes:
  3306   - classes division_ring_inverse_zero, field_inverse_zero,
  3307     linordered_field_inverse_zero include rule inverse 0 = 0 --
  3308     subsumes former division_by_zero class;
  3309   - numerous lemmas have been ported from field to division_ring.
  3310 INCOMPATIBILITY.
  3311 
  3312 * Refined algebra theorem collections:
  3313   - dropped theorem group group_simps, use algebra_simps instead;
  3314   - dropped theorem group ring_simps, use field_simps instead;
  3315   - proper theorem collection field_simps subsumes former theorem
  3316     groups field_eq_simps and field_simps;
  3317   - dropped lemma eq_minus_self_iff which is a duplicate for
  3318     equal_neg_zero.
  3319 INCOMPATIBILITY.
  3320 
  3321 * Theory Finite_Set and List: some lemmas have been generalized from
  3322 sets to lattices:
  3323 
  3324   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  3325   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  3326   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  3327   union_Union_fold_union        ~> sup_Sup_fold_sup
  3328   Inter_fold_inter              ~> Inf_fold_inf
  3329   Union_fold_union              ~> Sup_fold_sup
  3330   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  3331   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  3332   INTER_fold_inter              ~> INFI_fold_inf
  3333   UNION_fold_union              ~> SUPR_fold_sup
  3334 
  3335 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  3336 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  3337 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  3338 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  3339 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  3340 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  3341 
  3342 * Reorganized theory Multiset: swapped notation of pointwise and
  3343 multiset order:
  3344 
  3345   - pointwise ordering is instance of class order with standard syntax
  3346     <= and <;
  3347   - multiset ordering has syntax <=# and <#; partial order properties
  3348     are provided by means of interpretation with prefix
  3349     multiset_order;
  3350   - less duplication, less historical organization of sections,
  3351     conversion from associations lists to multisets, rudimentary code
  3352     generation;
  3353   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  3354     if needed.
  3355 
  3356 Renamed:
  3357 
  3358   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  3359   multi_count_ext  ~>  multiset_ext
  3360   diff_union_inverse2  ~>  diff_union_cancelR
  3361 
  3362 INCOMPATIBILITY.
  3363 
  3364 * Theory Permutation: replaced local "remove" by List.remove1.
  3365 
  3366 * Code generation: ML and OCaml code is decorated with signatures.
  3367 
  3368 * Theory List: added transpose.
  3369 
  3370 * Library/Nat_Bijection.thy is a collection of bijective functions
  3371 between nat and other types, which supersedes the older libraries
  3372 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  3373 
  3374   Constants:
  3375   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  3376   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  3377   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  3378   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  3379   Countable.pair_encode           ~> prod_encode
  3380   NatIso.prod2nat                 ~> prod_encode
  3381   NatIso.nat2prod                 ~> prod_decode
  3382   NatIso.sum2nat                  ~> sum_encode
  3383   NatIso.nat2sum                  ~> sum_decode
  3384   NatIso.list2nat                 ~> list_encode
  3385   NatIso.nat2list                 ~> list_decode
  3386   NatIso.set2nat                  ~> set_encode
  3387   NatIso.nat2set                  ~> set_decode
  3388 
  3389   Lemmas:
  3390   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  3391   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  3392   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  3393   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  3394   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  3395   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  3396   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  3397   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  3398   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  3399   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  3400   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  3401   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  3402   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  3403 
  3404 * Sledgehammer:
  3405   - Renamed ATP commands:
  3406     atp_info     ~> sledgehammer running_atps
  3407     atp_kill     ~> sledgehammer kill_atps
  3408     atp_messages ~> sledgehammer messages
  3409     atp_minimize ~> sledgehammer minimize
  3410     print_atps   ~> sledgehammer available_atps
  3411     INCOMPATIBILITY.
  3412   - Added user's manual ("isabelle doc sledgehammer").
  3413   - Added option syntax and "sledgehammer_params" to customize
  3414     Sledgehammer's behavior.  See the manual for details.
  3415   - Modified the Isar proof reconstruction code so that it produces
  3416     direct proofs rather than proofs by contradiction.  (This feature
  3417     is still experimental.)
  3418   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  3419     full-typed mode.
  3420   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  3421 
  3422 * Nitpick:
  3423   - Added and implemented "binary_ints" and "bits" options.
  3424   - Added "std" option and implemented support for nonstandard models.
  3425   - Added and implemented "finitize" option to improve the precision
  3426     of infinite datatypes based on a monotonicity analysis.
  3427   - Added support for quotient types.
  3428   - Added support for "specification" and "ax_specification"
  3429     constructs.
  3430   - Added support for local definitions (for "function" and
  3431     "termination" proofs).
  3432   - Added support for term postprocessors.
  3433   - Optimized "Multiset.multiset" and "FinFun.finfun".
  3434   - Improved efficiency of "destroy_constrs" optimization.
  3435   - Fixed soundness bugs related to "destroy_constrs" optimization and
  3436     record getters.
  3437   - Fixed soundness bug related to higher-order constructors.
  3438   - Fixed soundness bug when "full_descrs" is enabled.
  3439   - Improved precision of set constructs.
  3440   - Added "atoms" option.
  3441   - Added cache to speed up repeated Kodkod invocations on the same
  3442     problems.
  3443   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  3444     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  3445     "SAT4J_Light".  INCOMPATIBILITY.
  3446   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  3447     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  3448   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  3449 
  3450 * Method "induct" now takes instantiations of the form t, where t is not
  3451   a variable, as a shorthand for "x == t", where x is a fresh variable.
  3452   If this is not intended, t has to be enclosed in parentheses.
  3453   By default, the equalities generated by definitional instantiations
  3454   are pre-simplified, which may cause parameters of inductive cases
  3455   to disappear, or may even delete some of the inductive cases.
  3456   Use "induct (no_simp)" instead of "induct" to restore the old
  3457   behaviour. The (no_simp) option is also understood by the "cases"
  3458   and "nominal_induct" methods, which now perform pre-simplification, too.
  3459   INCOMPATIBILITY.
  3460 
  3461 
  3462 *** HOLCF ***
  3463 
  3464 * Variable names in lemmas generated by the domain package have
  3465 changed; the naming scheme is now consistent with the HOL datatype
  3466 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  3467 
  3468 * The domain package no longer defines the function "foo_copy" for
  3469 recursive domain "foo".  The reach lemma is now stated directly in
  3470 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  3471 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  3472 
  3473 * Most definedness lemmas generated by the domain package (previously
  3474 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  3475 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  3476 Proofs that used definedness lemmas as intro rules may break,
  3477 potential INCOMPATIBILITY.
  3478 
  3479 * Induction and casedist rules generated by the domain package now
  3480 declare proper case_names (one called "bottom", and one named for each
  3481 constructor).  INCOMPATIBILITY.
  3482 
  3483 * For mutually-recursive domains, separate "reach" and "take_lemma"
  3484 rules are generated for each domain, INCOMPATIBILITY.
  3485 
  3486   foo_bar.reach       ~> foo.reach  bar.reach
  3487   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  3488 
  3489 * Some lemmas generated by the domain package have been renamed for
  3490 consistency with the datatype package, INCOMPATIBILITY.
  3491 
  3492   foo.ind        ~> foo.induct
  3493   foo.finite_ind ~> foo.finite_induct
  3494   foo.coind      ~> foo.coinduct
  3495   foo.casedist   ~> foo.exhaust
  3496   foo.exhaust    ~> foo.nchotomy
  3497 
  3498 * For consistency with other definition packages, the fixrec package
  3499 now generates qualified theorem names, INCOMPATIBILITY.
  3500 
  3501   foo_simps  ~> foo.simps
  3502   foo_unfold ~> foo.unfold
  3503   foo_induct ~> foo.induct
  3504 
  3505 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  3506 method and internal fixrec proofs now use the default simpset instead.
  3507 INCOMPATIBILITY.
  3508 
  3509 * The "contlub" predicate has been removed.  Proof scripts should use
  3510 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  3511 
  3512 * The "admw" predicate has been removed, INCOMPATIBILITY.
  3513 
  3514 * The constants cpair, cfst, and csnd have been removed in favor of
  3515 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  3516 
  3517 
  3518 *** ML ***
  3519 
  3520 * Antiquotations for basic formal entities:
  3521 
  3522     @{class NAME}         -- type class
  3523     @{class_syntax NAME}  -- syntax representation of the above
  3524 
  3525     @{type_name NAME}     -- logical type
  3526     @{type_abbrev NAME}   -- type abbreviation
  3527     @{nonterminal NAME}   -- type of concrete syntactic category
  3528     @{type_syntax NAME}   -- syntax representation of any of the above
  3529 
  3530     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  3531     @{const_abbrev NAME}  -- abbreviated constant
  3532     @{const_syntax NAME}  -- syntax representation of any of the above
  3533 
  3534 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  3535 syntax constant (cf. 'syntax' command).
  3536 
  3537 * Antiquotation @{make_string} inlines a function to print arbitrary
  3538 values similar to the ML toplevel.  The result is compiler dependent
  3539 and may fall back on "?" in certain situations.
  3540 
  3541 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  3542 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  3543 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  3544 not work with the asynchronous Isar document model.
  3545 
  3546 * Configuration options now admit dynamic default values, depending on
  3547 the context or even global references.
  3548 
  3549 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  3550 uses an efficient external library if available (for Poly/ML).
  3551 
  3552 * Renamed some important ML structures, while keeping the old names
  3553 for some time as aliases within the structure Legacy:
  3554 
  3555   OuterKeyword  ~>  Keyword
  3556   OuterLex      ~>  Token
  3557   OuterParse    ~>  Parse
  3558   OuterSyntax   ~>  Outer_Syntax
  3559   PrintMode     ~>  Print_Mode
  3560   SpecParse     ~>  Parse_Spec
  3561   ThyInfo       ~>  Thy_Info
  3562   ThyLoad       ~>  Thy_Load
  3563   ThyOutput     ~>  Thy_Output
  3564   TypeInfer     ~>  Type_Infer
  3565 
  3566 Note that "open Legacy" simplifies porting of sources, but forgetting
  3567 to remove it again will complicate porting again in the future.
  3568 
  3569 * Most operations that refer to a global context are named
  3570 accordingly, e.g. Simplifier.global_context or
  3571 ProofContext.init_global.  There are some situations where a global
  3572 context actually works, but under normal circumstances one needs to
  3573 pass the proper local context through the code!
  3574 
  3575 * Discontinued old TheoryDataFun with its copy/init operation -- data
  3576 needs to be pure.  Functor Theory_Data_PP retains the traditional
  3577 Pretty.pp argument to merge, which is absent in the standard
  3578 Theory_Data version.
  3579 
  3580 * Sorts.certify_sort and derived "cert" operations for types and terms
  3581 no longer minimize sorts.  Thus certification at the boundary of the
  3582 inference kernel becomes invariant under addition of class relations,
  3583 which is an important monotonicity principle.  Sorts are now minimized
  3584 in the syntax layer only, at the boundary between the end-user and the
  3585 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  3586 explicitly in rare situations.
  3587 
  3588 * Renamed old-style Drule.standard to Drule.export_without_context, to
  3589 emphasize that this is in no way a standard operation.
  3590 INCOMPATIBILITY.
  3591 
  3592 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  3593 usual for resolution.  Rare INCOMPATIBILITY.
  3594 
  3595 * Renamed varify/unvarify operations to varify_global/unvarify_global
  3596 to emphasize that these only work in a global situation (which is
  3597 quite rare).
  3598 
  3599 * Curried take and drop in library.ML; negative length is interpreted
  3600 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  3601 
  3602 * Proof terms: type substitutions on proof constants now use canonical
  3603 order of type variables.  INCOMPATIBILITY for tools working with proof
  3604 terms.
  3605 
  3606 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  3607 may no longer carry premises.  User-level specifications are
  3608 transformed accordingly by Thm.add_axiom/add_def.
  3609 
  3610 
  3611 *** System ***
  3612 
  3613 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  3614 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  3615 proof terms are enabled unconditionally in the new HOL-Proofs image.
  3616 
  3617 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  3618 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  3619 respectively.
  3620 
  3621 * Old lib/scripts/polyml-platform is superseded by the
  3622 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  3623 variant, even on a 64 bit machine.  The following example setting
  3624 prefers 64 bit if available:
  3625 
  3626   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  3627 
  3628 * The preliminary Isabelle/jEdit application demonstrates the emerging
  3629 Isabelle/Scala layer for advanced prover interaction and integration.
  3630 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  3631 component.
  3632 
  3633 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  3634 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  3635 similar to the default assignment of the document preparation system
  3636 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  3637 provides some operations for direct access to the font without asking
  3638 the user for manual installation.
  3639 
  3640 
  3641 
  3642 New in Isabelle2009-1 (December 2009)
  3643 -------------------------------------
  3644 
  3645 *** General ***
  3646 
  3647 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  3648 one backslash should be used, even in ML sources.
  3649 
  3650 
  3651 *** Pure ***
  3652 
  3653 * Locale interpretation propagates mixins along the locale hierarchy.
  3654 The currently only available mixins are the equations used to map
  3655 local definitions to terms of the target domain of an interpretation.
  3656 
  3657 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  3658 loc" to print all interpretations of locale "loc" in the theory.
  3659 Interpretations in proofs are not shown.
  3660 
  3661 * Thoroughly revised locales tutorial.  New section on conditional
  3662 interpretation.
  3663 
  3664 * On instantiation of classes, remaining undefined class parameters
  3665 are formally declared.  INCOMPATIBILITY.
  3666 
  3667 
  3668 *** Document preparation ***
  3669 
  3670 * New generalized style concept for printing terms: @{foo (style) ...}
  3671 instead of @{foo_style style ...}  (old form is still retained for
  3672 backward compatibility).  Styles can be also applied for
  3673 antiquotations prop, term_type and typeof.
  3674 
  3675 
  3676 *** HOL ***
  3677 
  3678 * New proof method "smt" for a combination of first-order logic with
  3679 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  3680 fixed-size bitvectors; there is also basic support for higher-order
  3681 features (esp. lambda abstractions).  It is an incomplete decision
  3682 procedure based on external SMT solvers using the oracle mechanism;
  3683 for the SMT solver Z3, this method is proof-producing.  Certificates
  3684 are provided to avoid calling the external solvers solely for
  3685 re-checking proofs.  Due to a remote SMT service there is no need for
  3686 installing SMT solvers locally.  See src/HOL/SMT.
  3687 
  3688 * New commands to load and prove verification conditions generated by
  3689 the Boogie program verifier or derived systems (e.g. the Verifying C
  3690 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  3691 
  3692 * New counterexample generator tool 'nitpick' based on the Kodkod
  3693 relational model finder.  See src/HOL/Tools/Nitpick and
  3694 src/HOL/Nitpick_Examples.
  3695 
  3696 * New commands 'code_pred' and 'values' to invoke the predicate
  3697 compiler and to enumerate values of inductive predicates.
  3698 
  3699 * A tabled implementation of the reflexive transitive closure.
  3700 
  3701 * New implementation of quickcheck uses generic code generator;
  3702 default generators are provided for all suitable HOL types, records
  3703 and datatypes.  Old quickcheck can be re-activated importing theory
  3704 Library/SML_Quickcheck.
  3705 
  3706 * New testing tool Mirabelle for automated proof tools.  Applies
  3707 several tools and tactics like sledgehammer, metis, or quickcheck, to
  3708 every proof step in a theory.  To be used in batch mode via the
  3709 "mirabelle" utility.
  3710 
  3711 * New proof method "sos" (sum of squares) for nonlinear real
  3712 arithmetic (originally due to John Harison). It requires theory
  3713 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  3714 works well in practice on quantifier-free real arithmetic with +, -,
  3715 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  3716 inequalities between polynomials.  It makes use of external
  3717 semidefinite programming solvers.  Method "sos" generates a
  3718 certificate that can be pasted into the proof thus avoiding the need
  3719 to call an external tool every time the proof is checked.  See
  3720 src/HOL/Library/Sum_Of_Squares.
  3721 
  3722 * New method "linarith" invokes existing linear arithmetic decision
  3723 procedure only.
  3724 
  3725 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  3726 
  3727 * New Sledgehammer option "Full Types" in Proof General settings menu.
  3728 Causes full type information to be output to the ATPs.  This slows
  3729 ATPs down considerably but eliminates a source of unsound "proofs"
  3730 that fail later.
  3731 
  3732 * New method "metisFT": A version of metis that uses full type
  3733 information in order to avoid failures of proof reconstruction.
  3734 
  3735 * New evaluator "approximate" approximates an real valued term using
  3736 the same method as the approximation method.
  3737 
  3738 * Method "approximate" now supports arithmetic expressions as
  3739 boundaries of intervals and implements interval splitting and Taylor
  3740 series expansion.
  3741 
  3742 * ML antiquotation @{code_datatype} inserts definition of a datatype
  3743 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  3744 
  3745 * New theory SupInf of the supremum and infimum operators for sets of
  3746 reals.
  3747 
  3748 * New theory Probability, which contains a development of measure
  3749 theory, eventually leading to Lebesgue integration and probability.
  3750 
  3751 * Extended Multivariate Analysis to include derivation and Brouwer's
  3752 fixpoint theorem.
  3753 
  3754 * Reorganization of number theory, INCOMPATIBILITY:
  3755   - new number theory development for nat and int, in theories Divides
  3756     and GCD as well as in new session Number_Theory
  3757   - some constants and facts now suffixed with _nat and _int
  3758     accordingly
  3759   - former session NumberTheory now named Old_Number_Theory, including
  3760     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  3761   - moved theory Pocklington from src/HOL/Library to
  3762     src/HOL/Old_Number_Theory
  3763 
  3764 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  3765 lcm of finite and infinite sets. It is shown that they form a complete
  3766 lattice.
  3767 
  3768 * Class semiring_div requires superclass no_zero_divisors and proof of
  3769 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  3770 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  3771 generalized to class semiring_div, subsuming former theorems
  3772 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  3773 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  3774 INCOMPATIBILITY.
  3775 
  3776 * Refinements to lattice classes and sets:
  3777   - less default intro/elim rules in locale variant, more default
  3778     intro/elim rules in class variant: more uniformity
  3779   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  3780     le_inf_iff
  3781   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  3782     sup_aci)
  3783   - renamed ACI to inf_sup_aci
  3784   - new class "boolean_algebra"
  3785   - class "complete_lattice" moved to separate theory
  3786     "Complete_Lattice"; corresponding constants (and abbreviations)
  3787     renamed and with authentic syntax:
  3788     Set.Inf ~>    Complete_Lattice.Inf
  3789     Set.Sup ~>    Complete_Lattice.Sup
  3790     Set.INFI ~>   Complete_Lattice.INFI
  3791     Set.SUPR ~>   Complete_Lattice.SUPR
  3792     Set.Inter ~>  Complete_Lattice.Inter
  3793     Set.Union ~>  Complete_Lattice.Union
  3794     Set.INTER ~>  Complete_Lattice.INTER
  3795     Set.UNION ~>  Complete_Lattice.UNION
  3796   - authentic syntax for
  3797     Set.Pow
  3798     Set.image
  3799   - mere abbreviations:
  3800     Set.empty               (for bot)
  3801     Set.UNIV                (for top)
  3802     Set.inter               (for inf, formerly Set.Int)
  3803     Set.union               (for sup, formerly Set.Un)
  3804     Complete_Lattice.Inter  (for Inf)
  3805     Complete_Lattice.Union  (for Sup)
  3806     Complete_Lattice.INTER  (for INFI)
  3807     Complete_Lattice.UNION  (for SUPR)
  3808   - object-logic definitions as far as appropriate
  3809 
  3810 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  3811 Un_subset_iff are explicitly deleted as default simp rules; then also
  3812 their lattice counterparts le_inf_iff and le_sup_iff have to be
  3813 deleted to achieve the desired effect.
  3814 
  3815 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  3816 rules by default any longer; the same applies to min_max.inf_absorb1
  3817 etc.  INCOMPATIBILITY.
  3818 
  3819 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  3820 pred_set_conv by default.  INCOMPATIBILITY.
  3821 
  3822 * Power operations on relations and functions are now one dedicated
  3823 constant "compow" with infix syntax "^^".  Power operation on
  3824 multiplicative monoids retains syntax "^" and is now defined generic
  3825 in class power.  INCOMPATIBILITY.
  3826 
  3827 * Relation composition "R O S" now has a more standard argument order:
  3828 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  3829 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  3830 break, since the O_assoc rule was not rewritten like this.  Fix using
  3831 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  3832 
  3833 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  3834 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  3835 INCOMPATIBILITY.
  3836 
  3837 * Most rules produced by inductive and datatype package have mandatory
  3838 prefixes.  INCOMPATIBILITY.
  3839 
  3840 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  3841 the attribute of the same name.  Each of the theorems in the list
  3842 DERIV_intros assumes composition with an additional function and
  3843 matches a variable to the derivative, which has to be solved by the
  3844 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  3845 of most elementary terms.  Former Maclauren.DERIV_tac and
  3846 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  3847 INCOMPATIBILITY.
  3848 
  3849 * Code generator attributes follow the usual underscore convention:
  3850     code_unfold     replaces    code unfold
  3851     code_post       replaces    code post
  3852     etc.
  3853   INCOMPATIBILITY.
  3854 
  3855 * Renamed methods:
  3856     sizechange -> size_change
  3857     induct_scheme -> induction_schema
  3858   INCOMPATIBILITY.
  3859 
  3860 * Discontinued abbreviation "arbitrary" of constant "undefined".
  3861 INCOMPATIBILITY, use "undefined" directly.
  3862 
  3863 * Renamed theorems:
  3864     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  3865     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  3866     Suc_plus1 -> Suc_eq_plus1
  3867     *anti_sym -> *antisym*
  3868     vector_less_eq_def -> vector_le_def
  3869   INCOMPATIBILITY.
  3870 
  3871 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  3872 INCOMPATIBILITY.
  3873 
  3874 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  3875 INCOMPATIBILITY.
  3876 
  3877 
  3878 *** HOLCF ***
  3879 
  3880 * Theory Representable defines a class "rep" of domains that are
  3881 representable (via an ep-pair) in the universal domain type "udom".
  3882 Instances are provided for all type constructors defined in HOLCF.
  3883 
  3884 * The 'new_domain' command is a purely definitional version of the
  3885 domain package, for representable domains.  Syntax is identical to the
  3886 old domain package.  The 'new_domain' package also supports indirect
  3887 recursion using previously-defined type constructors.  See
  3888 src/HOLCF/ex/New_Domain.thy for examples.
  3889 
  3890 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  3891 on the left-hand side of an equation, and then performs
  3892 simplification.  Rewriting is done using rules declared with the
  3893 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  3894 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  3895 
  3896 * The pattern-match compiler in 'fixrec' can now handle constructors
  3897 with HOL function types.  Pattern-match combinators for the Pair
  3898 constructor are pre-configured.
  3899 
  3900 * The 'fixrec' package now produces better fixed-point induction rules
  3901 for mutually-recursive definitions:  Induction rules have conclusions
  3902 of the form "P foo bar" instead of "P <foo, bar>".
  3903 
  3904 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  3905 been renamed to "below".  The name "below" now replaces "less" in many
  3906 theorem names.  (Legacy theorem names using "less" are still supported
  3907 as well.)
  3908 
  3909 * The 'fixrec' package now supports "bottom patterns".  Bottom
  3910 patterns can be used to generate strictness rules, or to make
  3911 functions more strict (much like the bang-patterns supported by the
  3912 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  3913 examples.
  3914 
  3915 
  3916 *** ML ***
  3917 
  3918 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  3919 errors and run-time exceptions, including detailed source positions.
  3920 
  3921 * Structure Name_Space (formerly NameSpace) now manages uniquely
  3922 identified entries, with some additional information such as source
  3923 position, logical grouping etc.
  3924 
  3925 * Theory and context data is now introduced by the simplified and
  3926 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  3927 to be pure, but the old TheoryDataFun for mutable data (with explicit
  3928 copy operation) is still available for some time.
  3929 
  3930 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  3931 provides a high-level programming interface to synchronized state
  3932 variables with atomic update.  This works via pure function
  3933 application within a critical section -- its runtime should be as
  3934 short as possible; beware of deadlocks if critical code is nested,
  3935 either directly or indirectly via other synchronized variables!
  3936 
  3937 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  3938 wraps raw ML references, explicitly indicating their non-thread-safe
  3939 behaviour.  The Isar toplevel keeps this structure open, to
  3940 accommodate Proof General as well as quick and dirty interactive
  3941 experiments with references.
  3942 
  3943 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  3944 parallel tactical reasoning.
  3945 
  3946 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  3947 are similar to SUBPROOF, but are slightly more flexible: only the
  3948 specified parts of the subgoal are imported into the context, and the
  3949 body tactic may introduce new subgoals and schematic variables.
  3950 
  3951 * Old tactical METAHYPS, which does not observe the proof context, has
  3952 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  3953 or Subgoal.FOCUS etc.
  3954 
  3955 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  3956 functors have their own ML name space there is no point to mark them
  3957 separately.)  Minor INCOMPATIBILITY.
  3958 
  3959 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  3960 
  3961 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  3962 INCOMPATIBILITY.
  3963 
  3964 * Operations of structure Skip_Proof no longer require quick_and_dirty
  3965 mode, which avoids critical setmp.
  3966 
  3967 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  3968 combinators for "args".  INCOMPATIBILITY, need to use simplified
  3969 Attrib/Method.setup introduced in Isabelle2009.
  3970 
  3971 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  3972 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  3973 last resort.  INCOMPATIBILITY.
  3974 
  3975 * Display.pretty_thm now requires a proper context (cf. former
  3976 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  3977 or even Display.pretty_thm_without_context as last resort.
  3978 INCOMPATIBILITY.
  3979 
  3980 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  3981 Syntax.pretty_typ/term directly, preferably with proper context
  3982 instead of global theory.
  3983 
  3984 
  3985 *** System ***
  3986 
  3987 * Further fine tuning of parallel proof checking, scales up to 8 cores
  3988 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  3989 usedir option -q.
  3990 
  3991 * Support for additional "Isabelle components" via etc/components, see
  3992 also the system manual.
  3993 
  3994 * The isabelle makeall tool now operates on all components with
  3995 IsaMakefile, not just hardwired "logics".
  3996 
  3997 * Removed "compress" option from isabelle-process and isabelle usedir;
  3998 this is always enabled.
  3999 
  4000 * Discontinued support for Poly/ML 4.x versions.
  4001 
  4002 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  4003 on a given logic image.  This requires the lighttpd webserver and is
  4004 currently supported on Linux only.
  4005 
  4006 
  4007 
  4008 New in Isabelle2009 (April 2009)
  4009 --------------------------------
  4010 
  4011 *** General ***
  4012 
  4013 * Simplified main Isabelle executables, with less surprises on
  4014 case-insensitive file-systems (such as Mac OS).
  4015 
  4016   - The main Isabelle tool wrapper is now called "isabelle" instead of
  4017     "isatool."
  4018 
  4019   - The former "isabelle" alias for "isabelle-process" has been
  4020     removed (should rarely occur to regular users).
  4021 
  4022   - The former "isabelle-interface" and its alias "Isabelle" have been
  4023     removed (interfaces are now regular Isabelle tools).
  4024 
  4025 Within scripts and make files, the Isabelle environment variables
  4026 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  4027 respectively.  (The latter are still available as legacy feature.)
  4028 
  4029 The old isabelle-interface wrapper could react in confusing ways if
  4030 the interface was uninstalled or changed otherwise.  Individual
  4031 interface tool configuration is now more explicit, see also the
  4032 Isabelle system manual.  In particular, Proof General is now available
  4033 via "isabelle emacs".
  4034 
  4035 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  4036 purge installed copies of Isabelle executables and re-run "isabelle
  4037 install -p ...", or use symlinks.
  4038 
  4039 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  4040 old ~/isabelle, which was slightly non-standard and apt to cause
  4041 surprises on case-insensitive file-systems (such as Mac OS).
  4042 
  4043 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  4044 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  4045 care is required when using older releases of Isabelle.  Note that
  4046 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  4047 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  4048 
  4049 * Proofs of fully specified statements are run in parallel on
  4050 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  4051 a regular 4-core machine, if the initial heap space is made reasonably
  4052 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  4053 
  4054 * The main reference manuals ("isar-ref", "implementation", and
  4055 "system") have been updated and extended.  Formally checked references
  4056 as hyperlinks are now available uniformly.
  4057 
  4058 
  4059 *** Pure ***
  4060 
  4061 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  4062 respects.  The most important changes are listed below.  See the
  4063 Tutorial on Locales ("locales" manual) for details.
  4064 
  4065 - In locale expressions, instantiation replaces renaming.  Parameters
  4066 must be declared in a for clause.  To aid compatibility with previous
  4067 parameter inheritance, in locale declarations, parameters that are not
  4068 'touched' (instantiation position "_" or omitted) are implicitly added
  4069 with their syntax at the beginning of the for clause.
  4070 
  4071 - Syntax from abbreviations and definitions in locales is available in
  4072 locale expressions and context elements.  The latter is particularly
  4073 useful in locale declarations.
  4074 
  4075 - More flexible mechanisms to qualify names generated by locale
  4076 expressions.  Qualifiers (prefixes) may be specified in locale
  4077 expressions, and can be marked as mandatory (syntax: "name!:") or
  4078 optional (syntax "name?:").  The default depends for plain "name:"
  4079 depends on the situation where a locale expression is used: in
  4080 commands 'locale' and 'sublocale' prefixes are optional, in
  4081 'interpretation' and 'interpret' prefixes are mandatory.  The old
  4082 implicit qualifiers derived from the parameter names of a locale are
  4083 no longer generated.
  4084 
  4085 - Command "sublocale l < e" replaces "interpretation l < e".  The
  4086 instantiation clause in "interpretation" and "interpret" (square
  4087 brackets) is no longer available.  Use locale expressions.
  4088 
  4089 - When converting proof scripts, mandatory qualifiers in
  4090 'interpretation' and 'interpret' should be retained by default, even
  4091 if this is an INCOMPATIBILITY compared to former behavior.  In the
  4092 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  4093 in locale expressions range over a single locale instance only.
  4094 
  4095 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  4096 In existing theorem specifications replace the includes element by the
  4097 respective context elements of the included locale, omitting those
  4098 that are already present in the theorem specification.  Multiple
  4099 assume elements of a locale should be replaced by a single one
  4100 involving the locale predicate.  In the proof body, declarations (most
  4101 notably theorems) may be regained by interpreting the respective
  4102 locales in the proof context as required (command "interpret").
  4103 
  4104 If using "includes" in replacement of a target solely because the
  4105 parameter types in the theorem are not as general as in the target,
  4106 consider declaring a new locale with additional type constraints on
  4107 the parameters (context element "constrains").
  4108 
  4109 - Discontinued "locale (open)".  INCOMPATIBILITY.
  4110 
  4111 - Locale interpretation commands no longer attempt to simplify goal.
  4112 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  4113 methods intro_locales and unfold_locales to clarify.
  4114 
  4115 - Locale interpretation commands no longer accept interpretation
  4116 attributes.  INCOMPATIBILITY.
  4117 
  4118 * Class declaration: so-called "base sort" must not be given in import
  4119 list any longer, but is inferred from the specification.  Particularly
  4120 in HOL, write
  4121 
  4122     class foo = ...
  4123 
  4124 instead of
  4125 
  4126     class foo = type + ...
  4127 
  4128 * Class target: global versions of theorems stemming do not carry a
  4129 parameter prefix any longer.  INCOMPATIBILITY.
  4130 
  4131 * Class 'instance' command no longer accepts attached definitions.
  4132 INCOMPATIBILITY, use proper 'instantiation' target instead.
  4133 
  4134 * Recovered hiding of consts, which was accidentally broken in
  4135 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  4136 makes c inaccessible; consider using ``hide (open) const c'' instead.
  4137 
  4138 * Slightly more coherent Pure syntax, with updated documentation in
  4139 isar-ref manual.  Removed locales meta_term_syntax and
  4140 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  4141 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  4142 directly in regular applications.
  4143 
  4144 * There is a new syntactic category "float_const" for signed decimal
  4145 fractions (e.g. 123.45 or -123.45).
  4146 
  4147 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  4148 interface with 'setup' command instead.
  4149 
  4150 * Command 'local_setup' is similar to 'setup', but operates on a local
  4151 theory context.
  4152 
  4153 * The 'axiomatization' command now only works within a global theory
  4154 context.  INCOMPATIBILITY.
  4155 
  4156 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  4157 hypotheses.  Sorts required in the course of reasoning need to be
  4158 covered by the constraints in the initial statement, completed by the
  4159 type instance information of the background theory.  Non-trivial sort
  4160 hypotheses, which rarely occur in practice, may be specified via
  4161 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  4162 
  4163   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  4164 
  4165 The result contains an implicit sort hypotheses as before --
  4166 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  4167 normalization.
  4168 
  4169 * Generalized Isar history, with support for linear undo, direct state
  4170 addressing etc.
  4171 
  4172 * Changed defaults for unify configuration options:
  4173 
  4174   unify_trace_bound = 50 (formerly 25)
  4175   unify_search_bound = 60 (formerly 30)
  4176 
  4177 * Different bookkeeping for code equations (INCOMPATIBILITY):
  4178 
  4179   a) On theory merge, the last set of code equations for a particular
  4180      constant is taken (in accordance with the policy applied by other
  4181      parts of the code generator framework).
  4182 
  4183   b) Code equations stemming from explicit declarations (e.g. code
  4184      attribute) gain priority over default code equations stemming
  4185      from definition, primrec, fun etc.
  4186 
  4187 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  4188 
  4189 * Unified theorem tables for both code generators.  Thus [code
  4190 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  4191 
  4192 * Command 'find_consts' searches for constants based on type and name
  4193 patterns, e.g.
  4194 
  4195     find_consts "_ => bool"
  4196 
  4197 By default, matching is against subtypes, but it may be restricted to
  4198 the whole type.  Searching by name is possible.  Multiple queries are
  4199 conjunctive and queries may be negated by prefixing them with a
  4200 hyphen:
  4201 
  4202     find_consts strict: "_ => bool" name: "Int" -"int => int"
  4203 
  4204 * New 'find_theorems' criterion "solves" matches theorems that
  4205 directly solve the current goal (modulo higher-order unification).
  4206 
  4207 * Auto solve feature for main theorem statements: whenever a new goal
  4208 is stated, "find_theorems solves" is called; any theorems that could
  4209 solve the lemma directly are listed as part of the goal state.
  4210 Cf. associated options in Proof General Isabelle settings menu,
  4211 enabled by default, with reasonable timeout for pathological cases of
  4212 higher-order unification.
  4213 
  4214 
  4215 *** Document preparation ***
  4216 
  4217 * Antiquotation @{lemma} now imitates a regular terminal proof,
  4218 demanding keyword 'by' and supporting the full method expression
  4219 syntax just like the Isar command 'by'.
  4220 
  4221 
  4222 *** HOL ***
  4223 
  4224 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  4225 points Main and Complex_Main remain as before.
  4226 
  4227 * Logic image HOL-Plain provides a minimal HOL with the most important
  4228 tools available (inductive, datatype, primrec, ...).  This facilitates
  4229 experimentation and tool development.  Note that user applications
  4230 (and library theories) should never refer to anything below theory
  4231 Main, as before.
  4232 
  4233 * Logic image HOL-Main stops at theory Main, and thus facilitates
  4234 experimentation due to shorter build times.
  4235 
  4236 * Logic image HOL-NSA contains theories of nonstandard analysis which
  4237 were previously part of former HOL-Complex.  Entry point Hyperreal
  4238 remains valid, but theories formerly using Complex_Main should now use
  4239 new entry point Hypercomplex.
  4240 
  4241 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  4242 Posix processes.  Avoids potentially expensive forking of the ML
  4243 process.  New thread-based implementation also works on non-Unix
  4244 platforms (Cygwin).  Provers are no longer hardwired, but defined
  4245 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  4246 commands are covered in the isar-ref manual.
  4247 
  4248 * Wrapper scripts for remote SystemOnTPTP service allows to use
  4249 sledgehammer without local ATP installation (Vampire etc.). Other
  4250 provers may be included via suitable ML wrappers, see also
  4251 src/HOL/ATP_Linkup.thy.
  4252 
  4253 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  4254 menu.
  4255 
  4256 * The metis method no longer fails because the theorem is too trivial
  4257 (contains the empty clause).
  4258 
  4259 * The metis method now fails in the usual manner, rather than raising
  4260 an exception, if it determines that it cannot prove the theorem.
  4261 
  4262 * Method "coherent" implements a prover for coherent logic (see also
  4263 src/Tools/coherent.ML).
  4264 
  4265 * Constants "undefined" and "default" replace "arbitrary".  Usually
  4266 "undefined" is the right choice to replace "arbitrary", though
  4267 logically there is no difference.  INCOMPATIBILITY.
  4268 
  4269 * Command "value" now integrates different evaluation mechanisms.  The
  4270 result of the first successful evaluation mechanism is printed.  In
  4271 square brackets a particular named evaluation mechanisms may be
  4272 specified (currently, [SML], [code] or [nbe]).  See further
  4273 src/HOL/ex/Eval_Examples.thy.
  4274 
  4275 * Normalization by evaluation now allows non-leftlinear equations.
  4276 Declare with attribute [code nbe].
  4277 
  4278 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  4279 as the structured Isar versions "cases" and "induct", cf. the
  4280 corresponding "cases" and "induct" attributes.  Mutual induction rules
  4281 are now presented as a list of individual projections
  4282 (e.g. foo_bar.inducts for types foo and bar); the old format with
  4283 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  4284 rare situations a different rule is selected --- notably nested tuple
  4285 elimination instead of former prod.exhaust: use explicit (case_tac t
  4286 rule: prod.exhaust) here.
  4287 
  4288 * Attributes "cases", "induct", "coinduct" support "del" option.
  4289 
  4290 * Removed fact "case_split_thm", which duplicates "case_split".
  4291 
  4292 * The option datatype has been moved to a new theory Option.  Renamed
  4293 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  4294 
  4295 * New predicate "strict_mono" classifies strict functions on partial
  4296 orders.  With strict functions on linear orders, reasoning about
  4297 (in)equalities is facilitated by theorems "strict_mono_eq",
  4298 "strict_mono_less_eq" and "strict_mono_less".
  4299 
  4300 * Some set operations are now proper qualified constants with
  4301 authentic syntax.  INCOMPATIBILITY:
  4302 
  4303     op Int ~>   Set.Int
  4304     op Un ~>    Set.Un
  4305     INTER ~>    Set.INTER
  4306     UNION ~>    Set.UNION
  4307     Inter ~>    Set.Inter
  4308     Union ~>    Set.Union
  4309     {} ~>       Set.empty
  4310     UNIV ~>     Set.UNIV
  4311 
  4312 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  4313 theory Set.
  4314 
  4315 * Auxiliary class "itself" has disappeared -- classes without any
  4316 parameter are treated as expected by the 'class' command.
  4317 
  4318 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  4319 
  4320 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  4321 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  4322 
  4323 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  4324 method "approximation".  It proves formulas on real values by using
  4325 interval arithmetic.  In the formulas are also the transcendental
  4326 functions sin, cos, tan, atan, ln, exp and the constant pi are
  4327 allowed. For examples see
  4328 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  4329 
  4330 * Theory "Reflection" now resides in HOL/Library.
  4331 
  4332 * Entry point to Word library now simply named "Word".
  4333 INCOMPATIBILITY.
  4334 
  4335 * Made source layout more coherent with logical distribution
  4336 structure:
  4337 
  4338     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  4339     src/HOL/Library/Code_Message.thy ~> src/HOL/
  4340     src/HOL/Library/GCD.thy ~> src/HOL/
  4341     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  4342     src/HOL/Library/Parity.thy ~> src/HOL/
  4343     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  4344     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  4345     src/HOL/Real/Lubs.thy ~> src/HOL/
  4346     src/HOL/Real/PReal.thy ~> src/HOL/
  4347     src/HOL/Real/Rational.thy ~> src/HOL/
  4348     src/HOL/Real/RComplete.thy ~> src/HOL/
  4349     src/HOL/Real/RealDef.thy ~> src/HOL/
  4350     src/HOL/Real/RealPow.thy ~> src/HOL/
  4351     src/HOL/Real/Real.thy ~> src/HOL/
  4352     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  4353     src/HOL/Complex/Complex.thy ~> src/HOL/
  4354     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  4355     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  4356     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  4357     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  4358     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  4359     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  4360     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  4361     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  4362     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  4363     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  4364     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  4365     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  4366     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  4367     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  4368     src/HOL/Real/Float ~> src/HOL/Library/
  4369     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  4370     src/HOL/Real/RealVector.thy ~> src/HOL/
  4371 
  4372     src/HOL/arith_data.ML ~> src/HOL/Tools
  4373     src/HOL/hologic.ML ~> src/HOL/Tools
  4374     src/HOL/simpdata.ML ~> src/HOL/Tools
  4375     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  4376     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  4377     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  4378     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  4379     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  4380     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  4381     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  4382 
  4383     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  4384     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  4385     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  4386     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  4387     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  4388     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  4389 
  4390 * If methods "eval" and "evaluation" encounter a structured proof
  4391 state with !!/==>, only the conclusion is evaluated to True (if
  4392 possible), avoiding strange error messages.
  4393 
  4394 * Method "sizechange" automates termination proofs using (a
  4395 modification of) the size-change principle.  Requires SAT solver.  See
  4396 src/HOL/ex/Termination.thy for examples.
  4397 
  4398 * Simplifier: simproc for let expressions now unfolds if bound
  4399 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  4400 
  4401 * Method "arith": Linear arithmetic now ignores all inequalities when
  4402 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  4403 
  4404 * New attribute "arith" for facts that should always be used
  4405 automatically by arithmetic. It is intended to be used locally in
  4406 proofs, e.g.
  4407 
  4408   assumes [arith]: "x > 0"
  4409 
  4410 Global usage is discouraged because of possible performance impact.
  4411 
  4412 * New classes "top" and "bot" with corresponding operations "top" and
  4413 "bot" in theory Orderings; instantiation of class "complete_lattice"
  4414 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  4415 
  4416 * Changed definition lemma "less_fun_def" in order to provide an
  4417 instance for preorders on functions; use lemma "less_le" instead.
  4418 INCOMPATIBILITY.
  4419 
  4420 * Theory Orderings: class "wellorder" moved here, with explicit
  4421 induction rule "less_induct" as assumption.  For instantiation of
  4422 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  4423 INCOMPATIBILITY.
  4424 
  4425 * Theory Orderings: added class "preorder" as superclass of "order".
  4426 INCOMPATIBILITY: Instantiation proofs for order, linorder
  4427 etc. slightly changed.  Some theorems named order_class.* now named
  4428 preorder_class.*.
  4429 
  4430 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  4431 "diag" to "Id_on".
  4432 
  4433 * Theory Finite_Set: added a new fold combinator of type
  4434 
  4435   ('a => 'b => 'b) => 'b => 'a set => 'b
  4436 
  4437 Occasionally this is more convenient than the old fold combinator
  4438 which is now defined in terms of the new one and renamed to
  4439 fold_image.
  4440 
  4441 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  4442 and "ring_simps" have been replaced by "algebra_simps" (which can be
  4443 extended with further lemmas!).  At the moment both still exist but
  4444 the former will disappear at some point.
  4445 
  4446 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  4447 class recpower.  Type-specific simp rules for various recpower types
  4448 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  4449 
  4450 rat_power_0    -> power_0
  4451 rat_power_Suc  -> power_Suc
  4452 realpow_0      -> power_0
  4453 realpow_Suc    -> power_Suc
  4454 complexpow_0   -> power_0
  4455 complexpow_Suc -> power_Suc
  4456 power_poly_0   -> power_0
  4457 power_poly_Suc -> power_Suc
  4458 
  4459 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  4460 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  4461 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  4462 of lemmas from Divides has been generalized from nat to class
  4463 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  4464 renames resulting from duplicate elimination:
  4465 
  4466     dvd_def_mod ~>          dvd_eq_mod_eq_0
  4467     zero_dvd_iff ~>         dvd_0_left_iff
  4468     dvd_0 ~>                dvd_0_right
  4469     DIVISION_BY_ZERO_DIV ~> div_by_0
  4470     DIVISION_BY_ZERO_MOD ~> mod_by_0
  4471     mult_div ~>             div_mult_self2_is_id
  4472     mult_mod ~>             mod_mult_self2_is_0
  4473 
  4474 * Theory IntDiv: removed many lemmas that are instances of class-based
  4475 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  4476 rename old lemmas as follows:
  4477 
  4478 dvd_diff               -> nat_dvd_diff
  4479 dvd_zminus_iff         -> dvd_minus_iff
  4480 mod_add1_eq            -> mod_add_eq
  4481 mod_mult1_eq           -> mod_mult_right_eq
  4482 mod_mult1_eq'          -> mod_mult_left_eq
  4483 mod_mult_distrib_mod   -> mod_mult_eq
  4484 nat_mod_add_left_eq    -> mod_add_left_eq
  4485 nat_mod_add_right_eq   -> mod_add_right_eq
  4486 nat_mod_div_trivial    -> mod_div_trivial
  4487 nat_mod_mod_trivial    -> mod_mod_trivial
  4488 zdiv_zadd_self1        -> div_add_self1
  4489 zdiv_zadd_self2        -> div_add_self2
  4490 zdiv_zmult_self1       -> div_mult_self2_is_id
  4491 zdiv_zmult_self2       -> div_mult_self1_is_id
  4492 zdvd_triv_left         -> dvd_triv_left
  4493 zdvd_triv_right        -> dvd_triv_right
  4494 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  4495 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  4496 zmod_zadd_left_eq      -> mod_add_left_eq
  4497 zmod_zadd_right_eq     -> mod_add_right_eq
  4498 zmod_zadd_self1        -> mod_add_self1
  4499 zmod_zadd_self2        -> mod_add_self2
  4500 zmod_zadd1_eq          -> mod_add_eq
  4501 zmod_zdiff1_eq         -> mod_diff_eq
  4502 zmod_zdvd_zmod         -> mod_mod_cancel
  4503 zmod_zmod_cancel       -> mod_mod_cancel
  4504 zmod_zmult_self1       -> mod_mult_self2_is_0
  4505 zmod_zmult_self2       -> mod_mult_self1_is_0
  4506 zmod_1                 -> mod_by_1
  4507 zdiv_1                 -> div_by_1
  4508 zdvd_abs1              -> abs_dvd_iff
  4509 zdvd_abs2              -> dvd_abs_iff
  4510 zdvd_refl              -> dvd_refl
  4511 zdvd_trans             -> dvd_trans
  4512 zdvd_zadd              -> dvd_add
  4513 zdvd_zdiff             -> dvd_diff
  4514 zdvd_zminus_iff        -> dvd_minus_iff
  4515 zdvd_zminus2_iff       -> minus_dvd_iff
  4516 zdvd_zmultD            -> dvd_mult_right
  4517 zdvd_zmultD2           -> dvd_mult_left
  4518 zdvd_zmult_mono        -> mult_dvd_mono
  4519 zdvd_0_right           -> dvd_0_right
  4520 zdvd_0_left            -> dvd_0_left_iff
  4521 zdvd_1_left            -> one_dvd
  4522 zminus_dvd_iff         -> minus_dvd_iff
  4523 
  4524 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  4525 
  4526 * The real numbers offer decimal input syntax: 12.34 is translated
  4527 into 1234/10^2. This translation is not reversed upon output.
  4528 
  4529 * Theory Library/Polynomial defines an abstract type 'a poly of
  4530 univariate polynomials with coefficients of type 'a.  In addition to
  4531 the standard ring operations, it also supports div and mod.  Code
  4532 generation is also supported, using list-style constructors.
  4533 
  4534 * Theory Library/Inner_Product defines a class of real_inner for real
  4535 inner product spaces, with an overloaded operation inner :: 'a => 'a
  4536 => real.  Class real_inner is a subclass of real_normed_vector from
  4537 theory RealVector.
  4538 
  4539 * Theory Library/Product_Vector provides instances for the product
  4540 type 'a * 'b of several classes from RealVector and Inner_Product.
  4541 Definitions of addition, subtraction, scalar multiplication, norms,
  4542 and inner products are included.
  4543 
  4544 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  4545 addition to the field operations, numerals and case syntax are also
  4546 supported.
  4547 
  4548 * Theory Library/Diagonalize provides constructive version of Cantor's
  4549 first diagonalization argument.
  4550 
  4551 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  4552 zlcm (for int); carried together from various gcd/lcm developements in
  4553 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  4554 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  4555 may recover tupled syntax as follows:
  4556 
  4557     hide (open) const gcd
  4558     abbreviation gcd where
  4559       "gcd == (%(a, b). GCD.gcd a b)"
  4560     notation (output)
  4561       GCD.gcd ("gcd '(_, _')")
  4562 
  4563 The same works for lcm, zgcd, zlcm.
  4564 
  4565 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  4566 instantiations for algebraic structures.  Removed some duplicate
  4567 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  4568 
  4569 * ML antiquotation @{code} takes a constant as argument and generates
  4570 corresponding code in background and inserts name of the corresponding
  4571 resulting ML value/function/datatype constructor binding in place.
  4572 All occurrences of @{code} with a single ML block are generated
  4573 simultaneously.  Provides a generic and safe interface for
  4574 instrumentalizing code generation.  See
  4575 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  4576 In future you ought to refrain from ad-hoc compiling generated SML
  4577 code on the ML toplevel.  Note that (for technical reasons) @{code}
  4578 cannot refer to constants for which user-defined serializations are
  4579 set.  Refer to the corresponding ML counterpart directly in that
  4580 cases.
  4581 
  4582 * Command 'rep_datatype': instead of theorem names the command now
  4583 takes a list of terms denoting the constructors of the type to be
  4584 represented as datatype.  The characteristic theorems have to be
  4585 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  4586 have disappeared in favour of existing ones:
  4587 
  4588     unit_induct                 ~> unit.induct
  4589     prod_induct                 ~> prod.induct
  4590     sum_induct                  ~> sum.induct
  4591     Suc_Suc_eq                  ~> nat.inject
  4592     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  4593 
  4594 
  4595 *** HOL-Algebra ***
  4596 
  4597 * New locales for orders and lattices where the equivalence relation
  4598 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  4599 locales use a record structure with field eq for the equivalence.
  4600 
  4601 * New theory of factorial domains.
  4602 
  4603 * Units_l_inv and Units_r_inv are now simp rules by default.
  4604 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  4605 and/or r_inv will now also require deletion of these lemmas.
  4606 
  4607 * Renamed the following theorems, INCOMPATIBILITY:
  4608 
  4609 UpperD ~> Upper_memD
  4610 LowerD ~> Lower_memD
  4611 least_carrier ~> least_closed
  4612 greatest_carrier ~> greatest_closed
  4613 greatest_Lower_above ~> greatest_Lower_below
  4614 one_zero ~> carrier_one_zero
  4615 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  4616 
  4617 
  4618 *** HOL-Nominal ***
  4619 
  4620 * Nominal datatypes can now contain type-variables.
  4621 
  4622 * Commands 'nominal_inductive' and 'equivariance' work with local
  4623 theory targets.
  4624 
  4625 * Nominal primrec can now works with local theory targets and its
  4626 specification syntax now conforms to the general format as seen in
  4627 'inductive' etc.
  4628 
  4629 * Method "perm_simp" honours the standard simplifier attributes
  4630 (no_asm), (no_asm_use) etc.
  4631 
  4632 * The new predicate #* is defined like freshness, except that on the
  4633 left hand side can be a set or list of atoms.
  4634 
  4635 * Experimental command 'nominal_inductive2' derives strong induction
  4636 principles for inductive definitions.  In contrast to
  4637 'nominal_inductive', which can only deal with a fixed number of
  4638 binders, it can deal with arbitrary expressions standing for sets of
  4639 atoms to be avoided.  The only inductive definition we have at the
  4640 moment that needs this generalisation is the typing rule for Lets in
  4641 the algorithm W:
  4642 
  4643  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  4644  -----------------------------------------------------------------
  4645          Gamma |- Let x be t1 in t2 : T2
  4646 
  4647 In this rule one wants to avoid all the binders that are introduced by
  4648 "close Gamma T1".  We are looking for other examples where this
  4649 feature might be useful.  Please let us know.
  4650 
  4651 
  4652 *** HOLCF ***
  4653 
  4654 * Reimplemented the simplification procedure for proving continuity
  4655 subgoals.  The new simproc is extensible; users can declare additional
  4656 continuity introduction rules with the attribute [cont2cont].
  4657 
  4658 * The continuity simproc now uses a different introduction rule for
  4659 solving continuity subgoals on terms with lambda abstractions.  In
  4660 some rare cases the new simproc may fail to solve subgoals that the
  4661 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  4662 Potential INCOMPATIBILITY.
  4663 
  4664 * Command 'fixrec': specification syntax now conforms to the general
  4665 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  4666 examples.  INCOMPATIBILITY.
  4667 
  4668 
  4669 *** ZF ***
  4670 
  4671 * Proof of Zorn's Lemma for partial orders.
  4672 
  4673 
  4674 *** ML ***
  4675 
  4676 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  4677 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  4678 depends on multithreading, so timouts will not work before Poly/ML
  4679 5.2.1!
  4680 
  4681 * High-level support for concurrent ML programming, see
  4682 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  4683 particularly convenient to organize independent functional
  4684 computations.  The concept of "synchronized variables" provides a
  4685 higher-order interface for components with shared state, avoiding the
  4686 delicate details of mutexes and condition variables.  (Requires
  4687 Poly/ML 5.2.1 or later.)
  4688 
  4689 * ML bindings produced via Isar commands are stored within the Isar
  4690 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  4691 become thread-safe and work with undo as expected (concerning
  4692 top-level bindings, not side-effects on global references).
  4693 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  4694 compiler at runtime; really global bindings need to be given outside a
  4695 theory.  (Requires Poly/ML 5.2 or later.)
  4696 
  4697 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  4698 context.  Top-level ML bindings are stored within the proof context in
  4699 a purely sequential fashion, disregarding the nested proof structure.
  4700 ML bindings introduced by 'ML_prf' are discarded at the end of the
  4701 proof.  (Requires Poly/ML 5.2 or later.)
  4702 
  4703 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  4704 and Method.setup, as well as Isar commands 'attribute_setup' and
  4705 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  4706 existing code accordingly, or use plain 'setup' together with old
  4707 Method.add_method.
  4708 
  4709 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  4710 to 'a -> thm, while results are always tagged with an authentic oracle
  4711 name.  The Isar command 'oracle' is now polymorphic, no argument type
  4712 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  4713 accordingly.  Note that extra performance may be gained by producing
  4714 the cterm carefully, avoiding slow Thm.cterm_of.
  4715 
  4716 * Simplified interface for defining document antiquotations via
  4717 ThyOutput.antiquotation, ThyOutput.output, and optionally
  4718 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  4719 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  4720 examples.
  4721 
  4722 * More systematic treatment of long names, abstract name bindings, and
  4723 name space operations.  Basic operations on qualified names have been
  4724 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  4725 Long_Name.append.  Old type bstring has been mostly replaced by
  4726 abstract type binding (see structure Binding), which supports precise
  4727 qualification by packages and local theory targets, as well as proper
  4728 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  4729 bstring values into Binding.name, or better pass through abstract
  4730 bindings everywhere.  See further src/Pure/General/long_name.ML,
  4731 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  4732 
  4733 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  4734 LocalTheory.note etc.) now refer to the *full* internal name, not the
  4735 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  4736 
  4737 * Disposed old type and term read functions (Sign.read_def_typ,
  4738 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  4739 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  4740 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  4741 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  4742 resort for legacy applications.
  4743 
  4744 * Disposed old declarations, tactics, tactic combinators that refer to
  4745 the simpset or claset of an implicit theory (such as Addsimps,
  4746 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  4747 embedded ML text, or local_simpset_of with a proper context passed as
  4748 explicit runtime argument.
  4749 
  4750 * Rules and tactics that read instantiations (read_instantiate,
  4751 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  4752 context, which is required for parsing and type-checking.  Moreover,
  4753 the variables are specified as plain indexnames, not string encodings
  4754 thereof.  INCOMPATIBILITY.
  4755 
  4756 * Generic Toplevel.add_hook interface allows to analyze the result of
  4757 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  4758 for theorem dependency output of transactions resulting in a new
  4759 theory state.
  4760 
  4761 * ML antiquotations: block-structured compilation context indicated by
  4762 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  4763 
  4764   @{binding name}                         - basic name binding
  4765   @{let ?pat = term}                      - term abbreviation (HO matching)
  4766   @{note name = fact}                     - fact abbreviation
  4767   @{thm fact}                             - singleton fact (with attributes)
  4768   @{thms fact}                            - general fact (with attributes)
  4769   @{lemma prop by method}                 - singleton goal
  4770   @{lemma prop by meth1 meth2}            - singleton goal
  4771   @{lemma prop1 ... propN by method}      - general goal
  4772   @{lemma prop1 ... propN by meth1 meth2} - general goal
  4773   @{lemma (open) ...}                     - open derivation
  4774 
  4775 
  4776 *** System ***
  4777 
  4778 * The Isabelle "emacs" tool provides a specific interface to invoke
  4779 Proof General / Emacs, with more explicit failure if that is not
  4780 installed (the old isabelle-interface script silently falls back on
  4781 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  4782 installation location of the Proof General distribution.
  4783 
  4784 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  4785 the Isabelle process into a JVM/Scala application.  See
  4786 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  4787 process wrapper has been discontinued.)
  4788 
  4789 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  4790 
  4791 * Various status messages (with exact source position information) are
  4792 emitted, if proper markup print mode is enabled.  This allows
  4793 user-interface components to provide detailed feedback on internal
  4794 prover operations.
  4795 
  4796 
  4797 
  4798 New in Isabelle2008 (June 2008)
  4799 -------------------------------
  4800 
  4801 *** General ***
  4802 
  4803 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  4804 and updated, with formally checked references as hyperlinks.
  4805 
  4806 * Theory loader: use_thy (and similar operations) no longer set the
  4807 implicit ML context, which was occasionally hard to predict and in
  4808 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  4809 provides a proper context already.
  4810 
  4811 * Theory loader: old-style ML proof scripts being *attached* to a thy
  4812 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  4813 'use' within a theory file will do the job.
  4814 
  4815 * Name space merge now observes canonical order, i.e. the second space
  4816 is inserted into the first one, while existing entries in the first
  4817 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  4818 swap theory imports.
  4819 
  4820 * Syntax: symbol \<chi> is now considered a letter.  Potential
  4821 INCOMPATIBILITY in identifier syntax etc.
  4822 
  4823 * Outer syntax: string tokens no longer admit escaped white space,
  4824 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  4825 white space without escapes.
  4826 
  4827 * Outer syntax: string tokens may contain arbitrary character codes
  4828 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  4829 "foo_bar".
  4830 
  4831 
  4832 *** Pure ***
  4833 
  4834 * Context-dependent token translations.  Default setup reverts locally
  4835 fixed variables, and adds hilite markup for undeclared frees.
  4836 
  4837 * Unused theorems can be found using the new command 'unused_thms'.
  4838 There are three ways of invoking it:
  4839 
  4840 (1) unused_thms
  4841      Only finds unused theorems in the current theory.
  4842 
  4843 (2) unused_thms thy_1 ... thy_n -
  4844      Finds unused theorems in the current theory and all of its ancestors,
  4845      excluding the theories thy_1 ... thy_n and all of their ancestors.
  4846 
  4847 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  4848      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  4849      their ancestors, excluding the theories thy_1 ... thy_n and all of
  4850      their ancestors.
  4851 
  4852 In order to increase the readability of the list produced by
  4853 unused_thms, theorems that have been created by a particular instance
  4854 of a theory command such as 'inductive' or 'function' are considered
  4855 to belong to the same "group", meaning that if at least one theorem in
  4856 this group is used, the other theorems in the same group are no longer
  4857 reported as unused.  Moreover, if all theorems in the group are
  4858 unused, only one theorem in the group is displayed.
  4859 
  4860 Note that proof objects have to be switched on in order for
  4861 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  4862 usually the case when using Proof General with the default settings).
  4863 
  4864 * Authentic naming of facts disallows ad-hoc overwriting of previous
  4865 theorems within the same name space.  INCOMPATIBILITY, need to remove
  4866 duplicate fact bindings, or even accidental fact duplications.  Note
  4867 that tools may maintain dynamically scoped facts systematically, using
  4868 PureThy.add_thms_dynamic.
  4869 
  4870 * Command 'hide' now allows to hide from "fact" name space as well.
  4871 
  4872 * Eliminated destructive theorem database, simpset, claset, and
  4873 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  4874 update of theories within ML code.
  4875 
  4876 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  4877 INCOMPATIBILITY, object-logics depending on former Pure require
  4878 additional setup PureThy.old_appl_syntax_setup; object-logics
  4879 depending on former CPure need to refer to Pure.
  4880 
  4881 * Commands 'use' and 'ML' are now purely functional, operating on
  4882 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  4883 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  4884 INCOMPATIBILITY.
  4885 
  4886 * Command 'setup': discontinued implicit version with ML reference.
  4887 
  4888 * Instantiation target allows for simultaneous specification of class
  4889 instance operations together with an instantiation proof.
  4890 Type-checking phase allows to refer to class operations uniformly.
  4891 See src/HOL/Complex/Complex.thy for an Isar example and
  4892 src/HOL/Library/Eval.thy for an ML example.
  4893 
  4894 * Indexing of literal facts: be more serious about including only
  4895 facts from the visible specification/proof context, but not the
  4896 background context (locale etc.).  Affects `prop` notation and method
  4897 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  4898 situations.
  4899 
  4900 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  4901 "(open)" option, which used to expose internal bound variables to the
  4902 proof text.
  4903 
  4904 * Isar statements: removed obsolete case "rule_context".
  4905 INCOMPATIBILITY, better use explicit fixes/assumes.
  4906 
  4907 * Locale proofs: default proof step now includes 'unfold_locales';
  4908 hence 'proof' without argument may be used to unfold locale
  4909 predicates.
  4910 
  4911 
  4912 *** Document preparation ***
  4913 
  4914 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  4915 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  4916 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  4917 spot); renamed link color from "darkblue" to "linkcolor" (default
  4918 value unchanged, can be redefined via \definecolor); no longer sets
  4919 "a4paper" option (unnecessary or even intrusive).
  4920 
  4921 * Antiquotation @{lemma A method} proves proposition A by the given
  4922 method (either a method name or a method name plus (optional) method
  4923 arguments in parentheses) and prints A just like @{prop A}.
  4924 
  4925 
  4926 *** HOL ***
  4927 
  4928 * New primrec package.  Specification syntax conforms in style to
  4929 definition/function/....  No separate induction rule is provided.  The
  4930 "primrec" command distinguishes old-style and new-style specifications
  4931 by syntax.  The former primrec package is now named OldPrimrecPackage.
  4932 When adjusting theories, beware: constants stemming from new-style
  4933 primrec specifications have authentic syntax.
  4934 
  4935 * Metis prover is now an order of magnitude faster, and also works
  4936 with multithreading.
  4937 
  4938 * Metis: the maximum number of clauses that can be produced from a
  4939 theorem is now given by the attribute max_clauses.  Theorems that
  4940 exceed this number are ignored, with a warning printed.
  4941 
  4942 * Sledgehammer no longer produces structured proofs by default. To
  4943 enable, declare [[sledgehammer_full = true]].  Attributes
  4944 reconstruction_modulus, reconstruction_sorts renamed
  4945 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  4946 
  4947 * Method "induct_scheme" derives user-specified induction rules
  4948 from well-founded induction and completeness of patterns. This factors
  4949 out some operations that are done internally by the function package
  4950 and makes them available separately.  See
  4951 src/HOL/ex/Induction_Scheme.thy for examples.
  4952 
  4953 * More flexible generation of measure functions for termination
  4954 proofs: Measure functions can be declared by proving a rule of the
  4955 form "is_measure f" and giving it the [measure_function] attribute.
  4956 The "is_measure" predicate is logically meaningless (always true), and
  4957 just guides the heuristic.  To find suitable measure functions, the
  4958 termination prover sets up the goal "is_measure ?f" of the appropriate
  4959 type and generates all solutions by prolog-style backwards proof using
  4960 the declared rules.
  4961 
  4962 This setup also deals with rules like 
  4963 
  4964   "is_measure f ==> is_measure (list_size f)"
  4965 
  4966 which accommodates nested datatypes that recurse through lists.
  4967 Similar rules are predeclared for products and option types.
  4968 
  4969 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  4970 
  4971   INCOMPATIBILITIES:
  4972 
  4973   - Definitions of overloaded constants on sets have to be replaced by
  4974     definitions on => and bool.
  4975 
  4976   - Some definitions of overloaded operators on sets can now be proved
  4977     using the definitions of the operators on => and bool.  Therefore,
  4978     the following theorems have been renamed:
  4979 
  4980       subset_def   -> subset_eq
  4981       psubset_def  -> psubset_eq
  4982       set_diff_def -> set_diff_eq
  4983       Compl_def    -> Compl_eq
  4984       Sup_set_def  -> Sup_set_eq
  4985       Inf_set_def  -> Inf_set_eq
  4986       sup_set_def  -> sup_set_eq
  4987       inf_set_def  -> inf_set_eq
  4988 
  4989   - Due to the incompleteness of the HO unification algorithm, some
  4990     rules such as subst may require manual instantiation, if some of
  4991     the unknowns in the rule is a set.
  4992 
  4993   - Higher order unification and forward proofs:
  4994     The proof pattern
  4995 
  4996       have "P (S::'a set)" <...>
  4997       then have "EX S. P S" ..
  4998 
  4999     no longer works (due to the incompleteness of the HO unification
  5000     algorithm) and must be replaced by the pattern
  5001 
  5002       have "EX S. P S"
  5003       proof
  5004         show "P S" <...>
  5005       qed
  5006 
  5007   - Calculational reasoning with subst (or similar rules):
  5008     The proof pattern
  5009 
  5010       have "P (S::'a set)" <...>
  5011       also have "S = T" <...>
  5012       finally have "P T" .
  5013 
  5014     no longer works (for similar reasons as the previous example) and
  5015     must be replaced by something like
  5016 
  5017       have "P (S::'a set)" <...>
  5018       moreover have "S = T" <...>
  5019       ultimately have "P T" by simp
  5020 
  5021   - Tactics or packages written in ML code:
  5022     Code performing pattern matching on types via
  5023 
  5024       Type ("set", [T]) => ...
  5025 
  5026     must be rewritten. Moreover, functions like strip_type or
  5027     binder_types no longer return the right value when applied to a
  5028     type of the form
  5029 
  5030       T1 => ... => Tn => U => bool
  5031 
  5032     rather than
  5033 
  5034       T1 => ... => Tn => U set
  5035 
  5036 * Merged theories Wellfounded_Recursion, Accessible_Part and
  5037 Wellfounded_Relations to theory Wellfounded.
  5038 
  5039 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  5040 
  5041 * Class finite no longer treats UNIV as class parameter.  Use class
  5042 enum from theory Library/Enum instead to achieve a similar effect.
  5043 INCOMPATIBILITY.
  5044 
  5045 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  5046 and "Cons".  INCOMPATIBILITY.
  5047 
  5048 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  5049 Potential INCOMPATIBILITY.
  5050 
  5051 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  5052 injective_fst_snd removed, use split_eta and prod_eqI instead.
  5053 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  5054 
  5055 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  5056 the same name in theory Orderings:
  5057 
  5058   less_trans
  5059   less_linear
  5060   le_imp_less_or_eq
  5061   le_less_trans
  5062   less_le_trans
  5063   less_not_sym
  5064   less_asym
  5065 
  5066 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  5067 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  5068 and different variable names.
  5069 
  5070 * Library/Option_ord.thy: Canonical order on option type.
  5071 
  5072 * Library/RBT.thy: Red-black trees, an efficient implementation of
  5073 finite maps.
  5074 
  5075 * Library/Countable.thy: Type class for countable types.
  5076 
  5077 * Theory Int: The representation of numerals has changed.  The infix
  5078 operator BIT and the bit datatype with constructors B0 and B1 have
  5079 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  5080 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  5081 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  5082 accordingly.
  5083 
  5084 * Theory Nat: definition of <= and < on natural numbers no longer
  5085 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  5086 le_def and less_def have disappeared.  Consider lemmas not_less
  5087 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  5088 
  5089 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  5090 (whose purpose mainly is for various fold_set functionals) have been
  5091 abandoned in favor of the existing algebraic classes
  5092 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  5093 lower_semilattice (resp. upper_semilattice) and linorder.
  5094 INCOMPATIBILITY.
  5095 
  5096 * Theory Transitive_Closure: induct and cases rules now declare proper
  5097 case_names ("base" and "step").  INCOMPATIBILITY.
  5098 
  5099 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  5100 lattices.  The form set-specific version is available as
  5101 Inductive.lfp_ordinal_induct_set.
  5102 
  5103 * Renamed theorems "power.simps" to "power_int.simps".
  5104 INCOMPATIBILITY.
  5105 
  5106 * Class semiring_div provides basic abstract properties of semirings
  5107 with division and modulo operations.  Subsumes former class dvd_mod.
  5108 
  5109 * Merged theories IntDef, Numeral and IntArith into unified theory
  5110 Int.  INCOMPATIBILITY.
  5111 
  5112 * Theory Library/Code_Index: type "index" now represents natural
  5113 numbers rather than integers.  INCOMPATIBILITY.
  5114 
  5115 * New class "uminus" with operation "uminus" (split of from class
  5116 "minus" which now only has operation "minus", binary).
  5117 INCOMPATIBILITY.
  5118 
  5119 * Constants "card", "internal_split", "option_map" now with authentic
  5120 syntax.  INCOMPATIBILITY.
  5121 
  5122 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  5123 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  5124 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  5125 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  5126 Sup_set_def, le_def, less_def, option_map_def now with object
  5127 equality.  INCOMPATIBILITY.
  5128 
  5129 * Records. Removed K_record, and replaced it by pure lambda term
  5130 %x. c. The simplifier setup is now more robust against eta expansion.
  5131 INCOMPATIBILITY: in cases explicitly referring to K_record.
  5132 
  5133 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  5134 
  5135 * Library/ListVector: new theory of arithmetic vector operations.
  5136 
  5137 * Library/Order_Relation: new theory of various orderings as sets of
  5138 pairs.  Defines preorders, partial orders, linear orders and
  5139 well-orders on sets and on types.
  5140 
  5141 
  5142 *** ZF ***
  5143 
  5144 * Renamed some theories to allow to loading both ZF and HOL in the
  5145 same session:
  5146 
  5147   Datatype  -> Datatype_ZF
  5148   Inductive -> Inductive_ZF
  5149   Int       -> Int_ZF
  5150   IntDiv    -> IntDiv_ZF
  5151   Nat       -> Nat_ZF
  5152   List      -> List_ZF
  5153   Main      -> Main_ZF
  5154 
  5155 INCOMPATIBILITY: ZF theories that import individual theories below
  5156 Main might need to be adapted.  Regular theory Main is still
  5157 available, as trivial extension of Main_ZF.
  5158 
  5159 
  5160 *** ML ***
  5161 
  5162 * ML within Isar: antiquotation @{const name} or @{const
  5163 name(typargs)} produces statically-checked Const term.
  5164 
  5165 * Functor NamedThmsFun: data is available to the user as dynamic fact
  5166 (of the same name).  Removed obsolete print command.
  5167 
  5168 * Removed obsolete "use_legacy_bindings" function.
  5169 
  5170 * The ``print mode'' is now a thread-local value derived from a global
  5171 template (the former print_mode reference), thus access becomes
  5172 non-critical.  The global print_mode reference is for session
  5173 management only; user-code should use print_mode_value,
  5174 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  5175 
  5176 * Functions system/system_out provide a robust way to invoke external
  5177 shell commands, with propagation of interrupts (requires Poly/ML
  5178 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  5179 
  5180 
  5181 *** System ***
  5182 
  5183 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  5184 in accordance with Proof General 3.7, which prefers GNU emacs.
  5185 
  5186 * isatool tty runs Isabelle process with plain tty interaction;
  5187 optional line editor may be specified via ISABELLE_LINE_EDITOR
  5188 setting, the default settings attempt to locate "ledit" and "rlwrap".
  5189 
  5190 * isatool browser now works with Cygwin as well, using general
  5191 "javapath" function defined in Isabelle process environment.
  5192 
  5193 * YXML notation provides a simple and efficient alternative to
  5194 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  5195 isatool yxml as described in the Isabelle system manual.
  5196 
  5197 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  5198 provides general wrapper for managing an Isabelle process in a robust
  5199 fashion, with ``cooked'' output from stdin/stderr.
  5200 
  5201 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  5202 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  5203 
  5204 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  5205 way of changing the user's settings is via
  5206 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  5207 script.
  5208 
  5209 * Multithreading.max_threads := 0 refers to the number of actual CPU
  5210 cores of the underlying machine, which is a good starting point for
  5211 optimal performance tuning.  The corresponding usedir option -M allows
  5212 "max" as an alias for "0".  WARNING: does not work on certain versions
  5213 of Mac OS (with Poly/ML 5.1).
  5214 
  5215 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  5216 adverse effect of Isabelle flooding interactive front-ends (notably
  5217 ProofGeneral / XEmacs).
  5218 
  5219 
  5220 
  5221 New in Isabelle2007 (November 2007)
  5222 -----------------------------------
  5223 
  5224 *** General ***
  5225 
  5226 * More uniform information about legacy features, notably a
  5227 warning/error of "Legacy feature: ...", depending on the state of the
  5228 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  5229 legacy features will disappear eventually.
  5230 
  5231 * Theory syntax: the header format ``theory A = B + C:'' has been
  5232 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  5233 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  5234 
  5235 * Theory syntax: the old non-Isar theory file format has been
  5236 discontinued altogether.  Note that ML proof scripts may still be used
  5237 with Isar theories; migration is usually quite simple with the ML
  5238 function use_legacy_bindings.  INCOMPATIBILITY.
  5239 
  5240 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  5241 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  5242 quotes.
  5243 
  5244 * Theory loader: be more serious about observing the static theory
  5245 header specifications (including optional directories), but not the
  5246 accidental file locations of previously successful loads.  The strict
  5247 update policy of former update_thy is now already performed by
  5248 use_thy, so the former has been removed; use_thys updates several
  5249 theories simultaneously, just as 'imports' within a theory header
  5250 specification, but without merging the results.  Potential
  5251 INCOMPATIBILITY: may need to refine theory headers and commands
  5252 ROOT.ML which depend on load order.
  5253 
  5254 * Theory loader: optional support for content-based file
  5255 identification, instead of the traditional scheme of full physical
  5256 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  5257 (cf. the system manual).  The new scheme allows to work with
  5258 non-finished theories in persistent session images, such that source
  5259 files may be moved later on without requiring reloads.
  5260 
  5261 * Theory loader: old-style ML proof scripts being *attached* to a thy
  5262 file (with the same base name as the theory) are considered a legacy
  5263 feature, which will disappear eventually. Even now, the theory loader
  5264 no longer maintains dependencies on such files.
  5265 
  5266 * Syntax: the scope for resolving ambiguities via type-inference is
  5267 now limited to individual terms, instead of whole simultaneous
  5268 specifications as before. This greatly reduces the complexity of the
  5269 syntax module and improves flexibility by separating parsing and
  5270 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  5271 'fixes' etc.) are required in rare situations.
  5272 
  5273 * Syntax: constants introduced by new-style packages ('definition',
  5274 'abbreviation' etc.) are passed through the syntax module in
  5275 ``authentic mode''. This means that associated mixfix annotations
  5276 really stick to such constants, independently of potential name space
  5277 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  5278 trees are represented slightly differently, may need to adapt syntax
  5279 translations accordingly. Use CONST marker in 'translations' and
  5280 @{const_syntax} antiquotation in 'parse_translation' etc.
  5281 
  5282 * Legacy goal package: reduced interface to the bare minimum required
  5283 to keep existing proof scripts running.  Most other user-level
  5284 functions are now part of the OldGoals structure, which is *not* open
  5285 by default (consider isatool expandshort before open OldGoals).
  5286 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  5287 these tend to cause confusion about the actual goal (!) context being
  5288 used here, which is not necessarily the same as the_context().
  5289 
  5290 * Command 'find_theorems': supports "*" wild-card in "name:"
  5291 criterion; "with_dups" option.  Certain ProofGeneral versions might
  5292 support a specific search form (see ProofGeneral/CHANGES).
  5293 
  5294 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  5295 by default, which means that "prems" (and also "fixed variables") are
  5296 suppressed from proof state output.  Note that the ProofGeneral
  5297 settings mechanism allows to change and save options persistently, but
  5298 older versions of Isabelle will fail to start up if a negative prems
  5299 limit is imposed.
  5300 
  5301 * Local theory targets may be specified by non-nested blocks of
  5302 ``context/locale/class ... begin'' followed by ``end''.  The body may
  5303 contain definitions, theorems etc., including any derived mechanism
  5304 that has been implemented on top of these primitives.  This concept
  5305 generalizes the existing ``theorem (in ...)'' towards more versatility
  5306 and scalability.
  5307 
  5308 * Proof General interface: proper undo of final 'end' command;
  5309 discontinued Isabelle/classic mode (ML proof scripts).
  5310 
  5311 
  5312 *** Document preparation ***
  5313 
  5314 * Added antiquotation @{theory name} which prints the given name,
  5315 after checking that it refers to a valid ancestor theory in the
  5316 current context.
  5317 
  5318 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  5319 check the given source text as ML type/structure, printing verbatim.
  5320 
  5321 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  5322 "c args == rhs" given in the current context.  (Any number of
  5323 arguments may be given on the LHS.)
  5324 
  5325 
  5326 *** Pure ***
  5327 
  5328 * The 'class' package offers a combination of axclass and locale to
  5329 achieve Haskell-like type classes in Isabelle.  Definitions and
  5330 theorems within a class context produce both relative results (with
  5331 implicit parameters according to the locale context), and polymorphic
  5332 constants with qualified polymorphism (according to the class
  5333 context).  Within the body context of a 'class' target, a separate
  5334 syntax layer ("user space type system") takes care of converting
  5335 between global polymorphic consts and internal locale representation.
  5336 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  5337 "isatool doc classes" provides a tutorial.
  5338 
  5339 * Generic code generator framework allows to generate executable
  5340 code for ML and Haskell (including Isabelle classes).  A short usage
  5341 sketch:
  5342 
  5343     internal compilation:
  5344         export_code <list of constants (term syntax)> in SML
  5345     writing SML code to a file:
  5346         export_code <list of constants (term syntax)> in SML <filename>
  5347     writing OCaml code to a file:
  5348         export_code <list of constants (term syntax)> in OCaml <filename>
  5349     writing Haskell code to a bunch of files:
  5350         export_code <list of constants (term syntax)> in Haskell <filename>
  5351 
  5352     evaluating closed propositions to True/False using code generation:
  5353         method ``eval''
  5354 
  5355 Reasonable default setup of framework in HOL.
  5356 
  5357 Theorem attributs for selecting and transforming function equations theorems:
  5358 
  5359     [code fun]:        select a theorem as function equation for a specific constant
  5360     [code fun del]:    deselect a theorem as function equation for a specific constant
  5361     [code inline]:     select an equation theorem for unfolding (inlining) in place
  5362     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  5363 
  5364 User-defined serializations (target in {SML, OCaml, Haskell}):
  5365 
  5366     code_const <and-list of constants (term syntax)>
  5367       {(target) <and-list of const target syntax>}+
  5368 
  5369     code_type <and-list of type constructors>
  5370       {(target) <and-list of type target syntax>}+
  5371 
  5372     code_instance <and-list of instances>
  5373       {(target)}+
  5374         where instance ::= <type constructor> :: <class>
  5375 
  5376     code_class <and_list of classes>
  5377       {(target) <and-list of class target syntax>}+
  5378         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  5379 
  5380 code_instance and code_class only are effective to target Haskell.
  5381 
  5382 For example usage see src/HOL/ex/Codegenerator.thy and
  5383 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  5384 generation from Isabelle/HOL theories is available via "isatool doc
  5385 codegen".
  5386 
  5387 * Code generator: consts in 'consts_code' Isar commands are now
  5388 referred to by usual term syntax (including optional type
  5389 annotations).
  5390 
  5391 * Command 'no_translations' removes translation rules from theory
  5392 syntax.
  5393 
  5394 * Overloaded definitions are now actually checked for acyclic
  5395 dependencies.  The overloading scheme is slightly more general than
  5396 that of Haskell98, although Isabelle does not demand an exact
  5397 correspondence to type class and instance declarations.
  5398 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  5399 exotic versions of overloading -- at the discretion of the user!
  5400 
  5401 Polymorphic constants are represented via type arguments, i.e. the
  5402 instantiation that matches an instance against the most general
  5403 declaration given in the signature.  For example, with the declaration
  5404 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  5405 as c(nat).  Overloading is essentially simultaneous structural
  5406 recursion over such type arguments.  Incomplete specification patterns
  5407 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  5408 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  5409 Command 'print_theory' outputs the normalized system of recursive
  5410 equations, see section "definitions".
  5411 
  5412 * Configuration options are maintained within the theory or proof
  5413 context (with name and type bool/int/string), providing a very simple
  5414 interface to a poor-man's version of general context data.  Tools may
  5415 declare options in ML (e.g. using Attrib.config_int) and then refer to
  5416 these values using Config.get etc.  Users may change options via an
  5417 associated attribute of the same name.  This form of context
  5418 declaration works particularly well with commands 'declare' or
  5419 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  5420 very easy to avoid global references, which would not observe Isar
  5421 toplevel undo/redo and fail to work with multithreading.
  5422 
  5423 Various global ML references of Pure and HOL have been turned into
  5424 configuration options:
  5425 
  5426   Unify.search_bound		unify_search_bound
  5427   Unify.trace_bound		unify_trace_bound
  5428   Unify.trace_simp		unify_trace_simp
  5429   Unify.trace_types		unify_trace_types
  5430   Simplifier.simp_depth_limit	simp_depth_limit
  5431   Blast.depth_limit		blast_depth_limit
  5432   DatatypeProp.dtK		datatype_distinctness_limit
  5433   fast_arith_neq_limit  	fast_arith_neq_limit
  5434   fast_arith_split_limit	fast_arith_split_limit
  5435 
  5436 * Named collections of theorems may be easily installed as context
  5437 data using the functor NamedThmsFun (see also
  5438 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  5439 attributes; there is also a toplevel print command.  This facility is
  5440 just a common case of general context data, which is the preferred way
  5441 for anything more complex than just a list of facts in canonical
  5442 order.
  5443 
  5444 * Isar: command 'declaration' augments a local theory by generic
  5445 declaration functions written in ML.  This enables arbitrary content
  5446 being added to the context, depending on a morphism that tells the
  5447 difference of the original declaration context wrt. the application
  5448 context encountered later on.
  5449 
  5450 * Isar: proper interfaces for simplification procedures.  Command
  5451 'simproc_setup' declares named simprocs (with match patterns, and body
  5452 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  5453 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  5454 
  5455 * Isar: an extra pair of brackets around attribute declarations
  5456 abbreviates a theorem reference involving an internal dummy fact,
  5457 which will be ignored later --- only the effect of the attribute on
  5458 the background context will persist.  This form of in-place
  5459 declarations is particularly useful with commands like 'declare' and
  5460 'using', for example ``have A using [[simproc a]] by simp''.
  5461 
  5462 * Isar: method "assumption" (and implicit closing of subproofs) now
  5463 takes simple non-atomic goal assumptions into account: after applying
  5464 an assumption as a rule the resulting subgoals are solved by atomic
  5465 assumption steps.  This is particularly useful to finish 'obtain'
  5466 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  5467 without referring to the original premise "!!x. P x ==> thesis" in the
  5468 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  5469 more permissive.
  5470 
  5471 * Isar: implicit use of prems from the Isar proof context is
  5472 considered a legacy feature.  Common applications like ``have A .''
  5473 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  5474 referencing facts explicitly here improves readability and
  5475 maintainability of proof texts.
  5476 
  5477 * Isar: improper proof element 'guess' is like 'obtain', but derives
  5478 the obtained context from the course of reasoning!  For example:
  5479 
  5480   assume "EX x y. A x & B y"   -- "any previous fact"
  5481   then guess x and y by clarify
  5482 
  5483 This technique is potentially adventurous, depending on the facts and
  5484 proof tools being involved here.
  5485 
  5486 * Isar: known facts from the proof context may be specified as literal
  5487 propositions, using ASCII back-quote syntax.  This works wherever
  5488 named facts used to be allowed so far, in proof commands, proof
  5489 methods, attributes etc.  Literal facts are retrieved from the context
  5490 according to unification of type and term parameters.  For example,
  5491 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  5492 theorems in the current context, then these are valid literal facts:
  5493 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  5494 
  5495 There is also a proof method "fact" which does the same composition
  5496 for explicit goal states, e.g. the following proof texts coincide with
  5497 certain special cases of literal facts:
  5498 
  5499   have "A" by fact                 ==  note `A`
  5500   have "A ==> B" by fact           ==  note `A ==> B`
  5501   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  5502   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  5503 
  5504 * Isar: ":" (colon) is no longer a symbolic identifier character in
  5505 outer syntax.  Thus symbolic identifiers may be used without
  5506 additional white space in declarations like this: ``assume *: A''.
  5507 
  5508 * Isar: 'print_facts' prints all local facts of the current context,
  5509 both named and unnamed ones.
  5510 
  5511 * Isar: 'def' now admits simultaneous definitions, e.g.:
  5512 
  5513   def x == "t" and y == "u"
  5514 
  5515 * Isar: added command 'unfolding', which is structurally similar to
  5516 'using', but affects both the goal state and facts by unfolding given
  5517 rewrite rules.  Thus many occurrences of the 'unfold' method or
  5518 'unfolded' attribute may be replaced by first-class proof text.
  5519 
  5520 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  5521 and command 'unfolding' now all support object-level equalities
  5522 (potentially conditional).  The underlying notion of rewrite rule is
  5523 analogous to the 'rule_format' attribute, but *not* that of the
  5524 Simplifier (which is usually more generous).
  5525 
  5526 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  5527 premises of a theorem by n. Useful in conjunction with drule.
  5528 
  5529 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  5530 method expression within a sandbox consisting of the first N
  5531 sub-goals, which need to exist.  For example, ``simp_all [3]''
  5532 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  5533 simplifies all new goals that emerge from applying rule foo to the
  5534 originally first one.
  5535 
  5536 * Isar: schematic goals are no longer restricted to higher-order
  5537 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  5538 expected.
  5539 
  5540 * Isar: the conclusion of a long theorem statement is now either
  5541 'shows' (a simultaneous conjunction, as before), or 'obtains'
  5542 (essentially a disjunction of cases with local parameters and
  5543 assumptions).  The latter allows to express general elimination rules
  5544 adequately; in this notation common elimination rules look like this:
  5545 
  5546   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  5547     assumes "EX x. P x"
  5548     obtains x where "P x"
  5549 
  5550   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  5551     assumes "A & B"
  5552     obtains A and B
  5553 
  5554   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  5555     assumes "A | B"
  5556     obtains
  5557       A
  5558     | B
  5559 
  5560 The subsequent classical rules even refer to the formal "thesis"
  5561 explicitly:
  5562 
  5563   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  5564     obtains "~ thesis"
  5565 
  5566   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  5567     obtains "thesis ==> something"
  5568 
  5569 The actual proof of an 'obtains' statement is analogous to that of the
  5570 Isar proof element 'obtain', only that there may be several cases.
  5571 Optional case names may be specified in parentheses; these will be
  5572 available both in the present proof and as annotations in the
  5573 resulting rule, for later use with the 'cases' method (cf. attribute
  5574 case_names).
  5575 
  5576 * Isar: the assumptions of a long theorem statement are available as
  5577 "assms" fact in the proof context.  This is more appropriate than the
  5578 (historical) "prems", which refers to all assumptions of the current
  5579 context, including those from the target locale, proof body etc.
  5580 
  5581 * Isar: 'print_statement' prints theorems from the current theory or
  5582 proof context in long statement form, according to the syntax of a
  5583 top-level lemma.
  5584 
  5585 * Isar: 'obtain' takes an optional case name for the local context
  5586 introduction rule (default "that").
  5587 
  5588 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  5589 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  5590 to occur.
  5591 
  5592 * Pure: syntax "CONST name" produces a fully internalized constant
  5593 according to the current context.  This is particularly useful for
  5594 syntax translations that should refer to internal constant
  5595 representations independently of name spaces.
  5596 
  5597 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  5598 instead of "FOO ". This allows multiple binder declarations to coexist
  5599 in the same context.  INCOMPATIBILITY.
  5600 
  5601 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  5602 primitive that also works in a locale context (both for constants and
  5603 fixed variables). Type declaration and internal syntactic representation
  5604 of given constants retrieved from the context. Likewise, the
  5605 'no_notation' command allows to remove given syntax annotations from the
  5606 current context.
  5607 
  5608 * Isar/locales: new derived specification elements 'axiomatization',
  5609 'definition', 'abbreviation', which support type-inference, admit
  5610 object-level specifications (equality, equivalence).  See also the
  5611 isar-ref manual.  Examples:
  5612 
  5613   axiomatization
  5614     eq  (infix "===" 50) where
  5615     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  5616 
  5617   definition "f x y = x + y + 1"
  5618   definition g where "g x = f x x"
  5619 
  5620   abbreviation
  5621     neq  (infix "=!=" 50) where
  5622     "x =!= y == ~ (x === y)"
  5623 
  5624 These specifications may be also used in a locale context.  Then the
  5625 constants being introduced depend on certain fixed parameters, and the
  5626 constant name is qualified by the locale base name.  An internal
  5627 abbreviation takes care for convenient input and output, making the
  5628 parameters implicit and using the original short name.  See also
  5629 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  5630 entities from a monomorphic theory.
  5631 
  5632 Presently, abbreviations are only available 'in' a target locale, but
  5633 not inherited by general import expressions.  Also note that
  5634 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  5635 'translations' in common applications.  The "no_abbrevs" print mode
  5636 prevents folding of abbreviations in term output.
  5637 
  5638 Concrete syntax is attached to specified constants in internal form,
  5639 independently of name spaces.  The parse tree representation is
  5640 slightly different -- use 'notation' instead of raw 'syntax', and
  5641 'translations' with explicit "CONST" markup to accommodate this.
  5642 
  5643 * Pure/Isar: unified syntax for new-style specification mechanisms
  5644 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  5645 full type inference and dummy patterns ("_").  For example:
  5646 
  5647   definition "K x _ = x"
  5648 
  5649   inductive conj for A B
  5650   where "A ==> B ==> conj A B"
  5651 
  5652 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  5653 the current context.  Print mode "no_abbrevs" prevents inversion of
  5654 abbreviations on output.
  5655 
  5656 * Isar/locales: improved parameter handling: use of locales "var" and
  5657 "struct" no longer necessary; - parameter renamings are no longer
  5658 required to be injective.  For example, this allows to define
  5659 endomorphisms as locale endom = homom mult mult h.
  5660 
  5661 * Isar/locales: changed the way locales with predicates are defined.
  5662 Instead of accumulating the specification, the imported expression is
  5663 now an interpretation.  INCOMPATIBILITY: different normal form of
  5664 locale expressions.  In particular, in interpretations of locales with
  5665 predicates, goals repesenting already interpreted fragments are not
  5666 removed automatically.  Use methods `intro_locales' and
  5667 `unfold_locales'; see below.
  5668 
  5669 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  5670 provide backward reasoning on locales predicates.  The methods are
  5671 aware of interpretations and discharge corresponding goals.
  5672 `intro_locales' is less aggressive then `unfold_locales' and does not
  5673 unfold predicates to assumptions.
  5674 
  5675 * Isar/locales: the order in which locale fragments are accumulated
  5676 has changed.  This enables to override declarations from fragments due
  5677 to interpretations -- for example, unwanted simp rules.
  5678 
  5679 * Isar/locales: interpretation in theories and proof contexts has been
  5680 extended.  One may now specify (and prove) equations, which are
  5681 unfolded in interpreted theorems.  This is useful for replacing
  5682 defined concepts (constants depending on locale parameters) by
  5683 concepts already existing in the target context.  Example:
  5684 
  5685   interpretation partial_order ["op <= :: [int, int] => bool"]
  5686     where "partial_order.less (op <=) (x::int) y = (x < y)"
  5687 
  5688 Typically, the constant `partial_order.less' is created by a
  5689 definition specification element in the context of locale
  5690 partial_order.
  5691 
  5692 * Method "induct": improved internal context management to support
  5693 local fixes and defines on-the-fly. Thus explicit meta-level
  5694 connectives !!  and ==> are rarely required anymore in inductive goals
  5695 (using object-logic connectives for this purpose has been long
  5696 obsolete anyway). Common proof patterns are explained in
  5697 src/HOL/Induct/Common_Patterns.thy, see also
  5698 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  5699 examples.
  5700 
  5701 * Method "induct": improved handling of simultaneous goals. Instead of
  5702 introducing object-level conjunction, the statement is now split into
  5703 several conclusions, while the corresponding symbolic cases are nested
  5704 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  5705 see src/HOL/Induct/Common_Patterns.thy, for example.
  5706 
  5707 * Method "induct": mutual induction rules are now specified as a list
  5708 of rule sharing the same induction cases. HOL packages usually provide
  5709 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  5710 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  5711 mutual induction rules differently, i.e. like this:
  5712 
  5713   (induct rule: foo_bar.inducts)
  5714   (induct set: foo bar)
  5715   (induct pred: foo bar)
  5716   (induct type: foo bar)
  5717 
  5718 The ML function ProjectRule.projections turns old-style rules into the
  5719 new format.
  5720 
  5721 * Method "coinduct": dual of induction, see
  5722 src/HOL/Library/Coinductive_List.thy for various examples.
  5723 
  5724 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  5725 considered a legacy feature.
  5726 
  5727 * Attribute "symmetric" produces result with standardized schematic
  5728 variables (index 0).  Potential INCOMPATIBILITY.
  5729 
  5730 * Simplifier: by default the simplifier trace only shows top level
  5731 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  5732 default. Thus there is less danger of being flooded by the trace. The
  5733 trace indicates where parts have been suppressed.
  5734   
  5735 * Provers/classical: removed obsolete classical version of elim_format
  5736 attribute; classical elim/dest rules are now treated uniformly when
  5737 manipulating the claset.
  5738 
  5739 * Provers/classical: stricter checks to ensure that supplied intro,
  5740 dest and elim rules are well-formed; dest and elim rules must have at
  5741 least one premise.
  5742 
  5743 * Provers/classical: attributes dest/elim/intro take an optional
  5744 weight argument for the rule (just as the Pure versions).  Weights are
  5745 ignored by automated tools, but determine the search order of single
  5746 rule steps.
  5747 
  5748 * Syntax: input syntax now supports dummy variable binding "%_. b",
  5749 where the body does not mention the bound variable.  Note that dummy
  5750 patterns implicitly depend on their context of bounds, which makes
  5751 "{_. _}" match any set comprehension as expected.  Potential
  5752 INCOMPATIBILITY -- parse translations need to cope with syntactic
  5753 constant "_idtdummy" in the binding position.
  5754 
  5755 * Syntax: removed obsolete syntactic constant "_K" and its associated
  5756 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  5757 for example "A -> B" => "Pi A (%_. B)".
  5758 
  5759 * Pure: 'class_deps' command visualizes the subclass relation, using
  5760 the graph browser tool.
  5761 
  5762 * Pure: 'print_theory' now suppresses certain internal declarations by
  5763 default; use '!' option for full details.
  5764 
  5765 
  5766 *** HOL ***
  5767 
  5768 * Method "metis" proves goals by applying the Metis general-purpose
  5769 resolution prover (see also http://gilith.com/software/metis/).
  5770 Examples are in the directory MetisExamples.  WARNING: the
  5771 Isabelle/HOL-Metis integration does not yet work properly with
  5772 multi-threading.
  5773   
  5774 * Command 'sledgehammer' invokes external automatic theorem provers as
  5775 background processes.  It generates calls to the "metis" method if
  5776 successful. These can be pasted into the proof.  Users do not have to
  5777 wait for the automatic provers to return.  WARNING: does not really
  5778 work with multi-threading.
  5779 
  5780 * New "auto_quickcheck" feature tests outermost goal statements for
  5781 potential counter-examples.  Controlled by ML references
  5782 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  5783 5000 milliseconds).  Fails silently if statements is outside of
  5784 executable fragment, or any other codgenerator problem occurs.
  5785 
  5786 * New constant "undefined" with axiom "undefined x = undefined".
  5787 
  5788 * Added class "HOL.eq", allowing for code generation with polymorphic
  5789 equality.
  5790 
  5791 * Some renaming of class constants due to canonical name prefixing in
  5792 the new 'class' package:
  5793 
  5794     HOL.abs ~> HOL.abs_class.abs
  5795     HOL.divide ~> HOL.divide_class.divide
  5796     0 ~> HOL.zero_class.zero
  5797     1 ~> HOL.one_class.one
  5798     op + ~> HOL.plus_class.plus
  5799     op - ~> HOL.minus_class.minus
  5800     uminus ~> HOL.minus_class.uminus
  5801     op * ~> HOL.times_class.times
  5802     op < ~> HOL.ord_class.less
  5803     op <= > HOL.ord_class.less_eq
  5804     Nat.power ~> Power.power_class.power
  5805     Nat.size ~> Nat.size_class.size
  5806     Numeral.number_of ~> Numeral.number_class.number_of
  5807     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  5808     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  5809     Orderings.min ~> Orderings.ord_class.min
  5810     Orderings.max ~> Orderings.ord_class.max
  5811     Divides.op div ~> Divides.div_class.div
  5812     Divides.op mod ~> Divides.div_class.mod
  5813     Divides.op dvd ~> Divides.div_class.dvd
  5814 
  5815 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  5816 
  5817 a) User-defined constants using any of the names "plus", "minus",
  5818 "times", "less" or "less_eq". The standard syntax translations for
  5819 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  5820 names.
  5821 
  5822 b) Variables named "plus", "minus", "times", "less", "less_eq"
  5823 INCOMPATIBILITY: use more specific names.
  5824 
  5825 c) Permutative equations (e.g. "a + b = b + a")
  5826 Since the change of names also changes the order of terms, permutative
  5827 rewrite rules may get applied in a different order. Experience shows
  5828 that this is rarely the case (only two adaptions in the whole Isabelle
  5829 distribution).  INCOMPATIBILITY: rewrite proofs
  5830 
  5831 d) ML code directly refering to constant names
  5832 This in general only affects hand-written proof tactics, simprocs and
  5833 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  5834 Consider using @{const_name} antiquotation.
  5835 
  5836 * New class "default" with associated constant "default".
  5837 
  5838 * Function "sgn" is now overloaded and available on int, real, complex
  5839 (and other numeric types), using class "sgn".  Two possible defs of
  5840 sgn are given as equational assumptions in the classes sgn_if and
  5841 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  5842 INCOMPATIBILITY.
  5843 
  5844 * Locale "partial_order" now unified with class "order" (cf. theory
  5845 Orderings), added parameter "less".  INCOMPATIBILITY.
  5846 
  5847 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  5848 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  5849 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  5850 
  5851 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  5852 changed order of proof goals in instance proofs.
  5853 
  5854 * The transitivity reasoner for partial and linear orders is set up
  5855 for classes "order" and "linorder".  Instances of the reasoner are available
  5856 in all contexts importing or interpreting the corresponding locales.
  5857 Method "order" invokes the reasoner separately; the reasoner
  5858 is also integrated with the Simplifier as a solver.  Diagnostic
  5859 command 'print_orders' shows the available instances of the reasoner
  5860 in the current context.
  5861 
  5862 * Localized monotonicity predicate in theory "Orderings"; integrated
  5863 lemmas max_of_mono and min_of_mono with this predicate.
  5864 INCOMPATIBILITY.
  5865 
  5866 * Formulation of theorem "dense" changed slightly due to integration
  5867 with new class dense_linear_order.
  5868 
  5869 * Uniform lattice theory development in HOL.
  5870 
  5871     constants "meet" and "join" now named "inf" and "sup"
  5872     constant "Meet" now named "Inf"
  5873 
  5874     classes "meet_semilorder" and "join_semilorder" now named
  5875       "lower_semilattice" and "upper_semilattice"
  5876     class "lorder" now named "lattice"
  5877     class "comp_lat" now named "complete_lattice"
  5878 
  5879     Instantiation of lattice classes allows explicit definitions
  5880     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  5881 
  5882   INCOMPATIBILITY.  Theorem renames:
  5883 
  5884     meet_left_le            ~> inf_le1
  5885     meet_right_le           ~> inf_le2
  5886     join_left_le            ~> sup_ge1
  5887     join_right_le           ~> sup_ge2
  5888     meet_join_le            ~> inf_sup_ord
  5889     le_meetI                ~> le_infI
  5890     join_leI                ~> le_supI
  5891     le_meet                 ~> le_inf_iff
  5892     le_join                 ~> ge_sup_conv
  5893     meet_idempotent         ~> inf_idem
  5894     join_idempotent         ~> sup_idem
  5895     meet_comm               ~> inf_commute
  5896     join_comm               ~> sup_commute
  5897     meet_leI1               ~> le_infI1
  5898     meet_leI2               ~> le_infI2
  5899     le_joinI1               ~> le_supI1
  5900     le_joinI2               ~> le_supI2
  5901     meet_assoc              ~> inf_assoc
  5902     join_assoc              ~> sup_assoc
  5903     meet_left_comm          ~> inf_left_commute
  5904     meet_left_idempotent    ~> inf_left_idem
  5905     join_left_comm          ~> sup_left_commute
  5906     join_left_idempotent    ~> sup_left_idem
  5907     meet_aci                ~> inf_aci
  5908     join_aci                ~> sup_aci
  5909     le_def_meet             ~> le_iff_inf
  5910     le_def_join             ~> le_iff_sup
  5911     join_absorp2            ~> sup_absorb2
  5912     join_absorp1            ~> sup_absorb1
  5913     meet_absorp1            ~> inf_absorb1
  5914     meet_absorp2            ~> inf_absorb2
  5915     meet_join_absorp        ~> inf_sup_absorb
  5916     join_meet_absorp        ~> sup_inf_absorb
  5917     distrib_join_le         ~> distrib_sup_le
  5918     distrib_meet_le         ~> distrib_inf_le
  5919 
  5920     add_meet_distrib_left   ~> add_inf_distrib_left
  5921     add_join_distrib_left   ~> add_sup_distrib_left
  5922     is_join_neg_meet        ~> is_join_neg_inf
  5923     is_meet_neg_join        ~> is_meet_neg_sup
  5924     add_meet_distrib_right  ~> add_inf_distrib_right
  5925     add_join_distrib_right  ~> add_sup_distrib_right
  5926     add_meet_join_distribs  ~> add_sup_inf_distribs
  5927     join_eq_neg_meet        ~> sup_eq_neg_inf
  5928     meet_eq_neg_join        ~> inf_eq_neg_sup
  5929     add_eq_meet_join        ~> add_eq_inf_sup
  5930     meet_0_imp_0            ~> inf_0_imp_0
  5931     join_0_imp_0            ~> sup_0_imp_0
  5932     meet_0_eq_0             ~> inf_0_eq_0
  5933     join_0_eq_0             ~> sup_0_eq_0
  5934     neg_meet_eq_join        ~> neg_inf_eq_sup
  5935     neg_join_eq_meet        ~> neg_sup_eq_inf
  5936     join_eq_if              ~> sup_eq_if
  5937 
  5938     mono_meet               ~> mono_inf
  5939     mono_join               ~> mono_sup
  5940     meet_bool_eq            ~> inf_bool_eq
  5941     join_bool_eq            ~> sup_bool_eq
  5942     meet_fun_eq             ~> inf_fun_eq
  5943     join_fun_eq             ~> sup_fun_eq
  5944     meet_set_eq             ~> inf_set_eq
  5945     join_set_eq             ~> sup_set_eq
  5946     meet1_iff               ~> inf1_iff
  5947     meet2_iff               ~> inf2_iff
  5948     meet1I                  ~> inf1I
  5949     meet2I                  ~> inf2I
  5950     meet1D1                 ~> inf1D1
  5951     meet2D1                 ~> inf2D1
  5952     meet1D2                 ~> inf1D2
  5953     meet2D2                 ~> inf2D2
  5954     meet1E                  ~> inf1E
  5955     meet2E                  ~> inf2E
  5956     join1_iff               ~> sup1_iff
  5957     join2_iff               ~> sup2_iff
  5958     join1I1                 ~> sup1I1
  5959     join2I1                 ~> sup2I1
  5960     join1I1                 ~> sup1I1
  5961     join2I2                 ~> sup1I2
  5962     join1CI                 ~> sup1CI
  5963     join2CI                 ~> sup2CI
  5964     join1E                  ~> sup1E
  5965     join2E                  ~> sup2E
  5966 
  5967     is_meet_Meet            ~> is_meet_Inf
  5968     Meet_bool_def           ~> Inf_bool_def
  5969     Meet_fun_def            ~> Inf_fun_def
  5970     Meet_greatest           ~> Inf_greatest
  5971     Meet_lower              ~> Inf_lower
  5972     Meet_set_def            ~> Inf_set_def
  5973 
  5974     Sup_def                 ~> Sup_Inf
  5975     Sup_bool_eq             ~> Sup_bool_def
  5976     Sup_fun_eq              ~> Sup_fun_def
  5977     Sup_set_eq              ~> Sup_set_def
  5978 
  5979     listsp_meetI            ~> listsp_infI
  5980     listsp_meet_eq          ~> listsp_inf_eq
  5981 
  5982     meet_min                ~> inf_min
  5983     join_max                ~> sup_max
  5984 
  5985 * Added syntactic class "size"; overloaded constant "size" now has
  5986 type "'a::size ==> bool"
  5987 
  5988 * Internal reorganisation of `size' of datatypes: size theorems
  5989 "foo.size" are no longer subsumed by "foo.simps" (but are still
  5990 simplification rules by default!); theorems "prod.size" now named
  5991 "*.size".
  5992 
  5993 * Class "div" now inherits from class "times" rather than "type".
  5994 INCOMPATIBILITY.
  5995 
  5996 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  5997 Linorder etc.  have disappeared; operations defined in terms of
  5998 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  5999 
  6000 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  6001 
  6002 * HOL-Word: New extensive library and type for generic, fixed size
  6003 machine words, with arithmetic, bit-wise, shifting and rotating
  6004 operations, reflection into int, nat, and bool lists, automation for
  6005 linear arithmetic (by automatic reflection into nat or int), including
  6006 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  6007 arithmetic type classes, supporting automatic simplification of
  6008 numerals on all operations.
  6009 
  6010 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  6011 
  6012 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  6013 
  6014 * Code generator library theories:
  6015   - Code_Integer represents HOL integers by big integer literals in target
  6016     languages.
  6017   - Code_Char represents HOL characters by character literals in target
  6018     languages.
  6019   - Code_Char_chr like Code_Char, but also offers treatment of character
  6020     codes; includes Code_Integer.
  6021   - Executable_Set allows to generate code for finite sets using lists.
  6022   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  6023     denominator).
  6024   - Executable_Real implements a subset of real numbers, namly those
  6025     representable by rational numbers.
  6026   - Efficient_Nat implements natural numbers by integers, which in general will
  6027     result in higher efficency; pattern matching with 0/Suc is eliminated;
  6028     includes Code_Integer.
  6029   - Code_Index provides an additional datatype index which is mapped to
  6030     target-language built-in integers.
  6031   - Code_Message provides an additional datatype message_string which is isomorphic to
  6032     strings; messages are mapped to target-language strings.
  6033 
  6034 * New package for inductive predicates
  6035 
  6036   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  6037 
  6038     inductive
  6039       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  6040       for z_1 :: U_1 and ... and z_n :: U_m
  6041     where
  6042       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  6043     | ...
  6044 
  6045   with full support for type-inference, rather than
  6046 
  6047     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  6048 
  6049     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  6050     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  6051 
  6052     inductive "s z_1 ... z_m"
  6053     intros
  6054       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  6055       ...
  6056 
  6057   For backward compatibility, there is a wrapper allowing inductive
  6058   sets to be defined with the new package via
  6059 
  6060     inductive_set
  6061       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  6062       for z_1 :: U_1 and ... and z_n :: U_m
  6063     where
  6064       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  6065     | ...
  6066 
  6067   or
  6068 
  6069     inductive_set
  6070       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  6071       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  6072       for z_1 :: U_1 and ... and z_n :: U_m
  6073     where
  6074       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  6075     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  6076     | ...
  6077 
  6078   if the additional syntax "p ..." is required.
  6079 
  6080   Numerous examples can be found in the subdirectories src/HOL/Auth,
  6081   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  6082 
  6083   INCOMPATIBILITIES:
  6084 
  6085   - Since declaration and definition of inductive sets or predicates
  6086     is no longer separated, abbreviations involving the newly
  6087     introduced sets or predicates must be specified together with the
  6088     introduction rules after the 'where' keyword (see above), rather
  6089     than before the actual inductive definition.
  6090 
  6091   - The variables in induction and elimination rules are now
  6092     quantified in the order of their occurrence in the introduction
  6093     rules, rather than in alphabetical order. Since this may break
  6094     some proofs, these proofs either have to be repaired, e.g. by
  6095     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  6096     statements of the form
  6097 
  6098       case (rule_i a_i_1 ... a_i_{k_i})
  6099 
  6100     or the old order of quantification has to be restored by explicitly adding
  6101     meta-level quantifiers in the introduction rules, i.e.
  6102 
  6103       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  6104 
  6105   - The format of the elimination rules is now
  6106 
  6107       p z_1 ... z_m x_1 ... x_n ==>
  6108         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  6109         ==> ... ==> P
  6110 
  6111     for predicates and
  6112 
  6113       (x_1, ..., x_n) : s z_1 ... z_m ==>
  6114         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  6115         ==> ... ==> P
  6116 
  6117     for sets rather than
  6118 
  6119       x : s z_1 ... z_m ==>
  6120         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  6121         ==> ... ==> P
  6122 
  6123     This may require terms in goals to be expanded to n-tuples
  6124     (e.g. using case_tac or simplification with the split_paired_all
  6125     rule) before the above elimination rule is applicable.
  6126 
  6127   - The elimination or case analysis rules for (mutually) inductive
  6128     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  6129     list of rules "p_1_..._p_k.elims" is no longer available.
  6130 
  6131 * New package "function"/"fun" for general recursive functions,
  6132 supporting mutual and nested recursion, definitions in local contexts,
  6133 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  6134 for small examples, and the separate tutorial on the function
  6135 package. The old recdef "package" is still available as before, but
  6136 users are encouraged to use the new package.
  6137 
  6138 * Method "lexicographic_order" automatically synthesizes termination
  6139 relations as lexicographic combinations of size measures. 
  6140 
  6141 * Case-expressions allow arbitrary constructor-patterns (including
  6142 "_") and take their order into account, like in functional
  6143 programming.  Internally, this is translated into nested
  6144 case-expressions; missing cases are added and mapped to the predefined
  6145 constant "undefined". In complicated cases printing may no longer show
  6146 the original input but the internal form. Lambda-abstractions allow
  6147 the same form of pattern matching: "% pat1 => e1 | ..." is an
  6148 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  6149 variable.
  6150 
  6151 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  6152 is an abbreviation for "of_nat :: nat => int". The simplification
  6153 rules for "of_nat" have been changed to work like "int" did
  6154 previously.  Potential INCOMPATIBILITY:
  6155   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  6156   - of_nat_diff and of_nat_mult are no longer default simp rules
  6157 
  6158 * Method "algebra" solves polynomial equations over (semi)rings using
  6159 Groebner bases. The (semi)ring structure is defined by locales and the
  6160 tool setup depends on that generic context. Installing the method for
  6161 a specific type involves instantiating the locale and possibly adding
  6162 declarations for computation on the coefficients.  The method is
  6163 already instantiated for natural numbers and for the axiomatic class
  6164 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  6165 CALCULEMUS 2007 for the general principles underlying this
  6166 architecture of context-aware proof-tools.
  6167 
  6168 * Method "ferrack" implements quantifier elimination over
  6169 special-purpose dense linear orders using locales (analogous to
  6170 "algebra"). The method is already installed for class
  6171 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  6172 rat, etc.
  6173 
  6174 * Former constant "List.op @" now named "List.append".  Use ML
  6175 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  6176 circumvent possible incompatibilities when working on ML level.
  6177 
  6178 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  6179 
  6180 * New function listsum :: 'a list => 'a for arbitrary monoids.
  6181 Special syntax: "SUM x <- xs. f x" (and latex variants)
  6182 
  6183 * New syntax for Haskell-like list comprehension (input only), eg.
  6184 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  6185 
  6186 * The special syntax for function "filter" has changed from [x :
  6187 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  6188 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  6189 
  6190 * [a..b] is now defined for arbitrary linear orders.  It used to be
  6191 defined on nat only, as an abbreviation for [a..<Suc b]
  6192 INCOMPATIBILITY.
  6193 
  6194 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  6195 
  6196 * New functions "sorted" and "sort" in src/HOL/List.thy.
  6197 
  6198 * New lemma collection field_simps (an extension of ring_simps) for
  6199 manipulating (in)equations involving division. Multiplies with all
  6200 denominators that can be proved to be non-zero (in equations) or
  6201 positive/negative (in inequations).
  6202 
  6203 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  6204 have been improved and renamed to ring_simps, group_simps and
  6205 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  6206 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  6207 
  6208 * Theory Library/Commutative_Ring: switched from recdef to function
  6209 package; constants add, mul, pow now curried.  Infix syntax for
  6210 algebraic operations.
  6211 
  6212 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  6213 INCOMPATIBILITY.
  6214 
  6215 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  6216 INCOMPATIBILITY.
  6217 
  6218 * HOL/records: generalised field-update to take a function on the
  6219 field rather than the new value: r(|A := x|) is translated to A_update
  6220 (K x) r The K-combinator that is internally used is called K_record.
  6221 INCOMPATIBILITY: Usage of the plain update functions has to be
  6222 adapted.
  6223  
  6224 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  6225 * x = 0, which are required for a semiring.  Richer structures do not
  6226 inherit from semiring_0 anymore, because this property is a theorem
  6227 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  6228 there is more to prove, but this is mostly trivial.
  6229 
  6230 * Class "recpower" is generalized to arbitrary monoids, not just
  6231 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  6232 commutativity or semiring properties additionally.
  6233 
  6234 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  6235 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  6236 better use 'abbreviation'.
  6237 
  6238 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  6239 
  6240 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  6241 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  6242 significant changes for setting up numeral syntax for types:
  6243   - New constants Numeral.pred and Numeral.succ instead
  6244       of former Numeral.bin_pred and Numeral.bin_succ.
  6245   - Use integer operations instead of bin_add, bin_mult and so on.
  6246   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  6247   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  6248 
  6249 See src/HOL/Integ/IntArith.thy for an example setup.
  6250 
  6251 * Command 'normal_form' computes the normal form of a term that may
  6252 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  6253 produces ``[b, c, a]'' (without proof).  This command is suitable for
  6254 heavy-duty computations because the functions are compiled to ML
  6255 first.  Correspondingly, a method "normalization" is provided.  See
  6256 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  6257 
  6258 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  6259 25 like -->); output depends on the "iff" print_mode, the default is
  6260 "A = B" (with priority 50).
  6261 
  6262 * Relations less (<) and less_eq (<=) are also available on type bool.
  6263 Modified syntax to disallow nesting without explicit parentheses,
  6264 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  6265 INCOMPATIBILITY.
  6266 
  6267 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  6268 
  6269 * Relation composition operator "op O" now has precedence 75 and binds
  6270 stronger than union and intersection. INCOMPATIBILITY.
  6271 
  6272 * The old set interval syntax "{m..n(}" (and relatives) has been
  6273 removed.  Use "{m..<n}" (and relatives) instead.
  6274 
  6275 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  6276 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  6277 ``declare [[simproc del: neq]]''.
  6278 
  6279 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  6280 True/False.
  6281 
  6282 * Theorem Cons_eq_map_conv no longer declared as "simp".
  6283 
  6284 * Theorem setsum_mult renamed to setsum_right_distrib.
  6285 
  6286 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  6287 ``rule'' method.
  6288 
  6289 * Reimplemented methods "sat" and "satx", with several improvements:
  6290 goals no longer need to be stated as "<prems> ==> False", equivalences
  6291 (i.e. "=" on type bool) are handled, variable names of the form
  6292 "lit_<n>" are no longer reserved, significant speedup.
  6293 
  6294 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  6295 zChaff is still supported as well.
  6296 
  6297 * 'inductive' and 'datatype': provide projections of mutual rules,
  6298 bundled as foo_bar.inducts;
  6299 
  6300 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  6301 Library.
  6302 
  6303 * Library: moved theory Accessible_Part to main HOL.
  6304 
  6305 * Library: added theory Coinductive_List of potentially infinite lists
  6306 as greatest fixed-point.
  6307 
  6308 * Library: added theory AssocList which implements (finite) maps as
  6309 association lists.
  6310 
  6311 * Method "evaluation" solves goals (i.e. a boolean expression)
  6312 efficiently by compiling it to ML.  The goal is "proved" (via an
  6313 oracle) if it evaluates to True.
  6314 
  6315 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  6316 also when invoked by the simplifier.  This results in the Simplifier
  6317 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  6318 Configuration option fast_arith_split_limit=0 recovers the old
  6319 behavior.
  6320 
  6321 * Support for hex (0x20) and binary (0b1001) numerals.
  6322 
  6323 * New method: reify eqs (t), where eqs are equations for an
  6324 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  6325 parameter, computes a term s::'b and a list xs::'a list and proves the
  6326 theorem I xs s = t. This is also known as reification or quoting. The
  6327 resulting theorem is applied to the subgoal to substitute t with I xs
  6328 s.  If t is omitted, the subgoal itself is reified.
  6329 
  6330 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  6331 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  6332 where f is supposed to be a computable function (in the sense of code
  6333 generattion). The method uses reify to compute s and xs as above then
  6334 applies corr_thm and uses normalization by evaluation to "prove" f s =
  6335 r and finally gets the theorem t = r, which is again applied to the
  6336 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  6337 
  6338 * Reflection: Automatic reification now handels binding, an example is
  6339 available in src/HOL/ex/ReflectionEx.thy
  6340 
  6341 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  6342 command 'statespace' that is similar to 'record', but introduces an
  6343 abstract specification based on the locale infrastructure instead of
  6344 HOL types.  This leads to extra flexibility in composing state spaces,
  6345 in particular multiple inheritance and renaming of components.
  6346 
  6347 
  6348 *** HOL-Complex ***
  6349 
  6350 * Hyperreal: Functions root and sqrt are now defined on negative real
  6351 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  6352 Nonnegativity side conditions have been removed from many lemmas, so
  6353 that more subgoals may now be solved by simplification; potential
  6354 INCOMPATIBILITY.
  6355 
  6356 * Real: new type classes formalize real normed vector spaces and
  6357 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  6358 and norm :: 'a => real.
  6359 
  6360 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  6361 reals into other types. The overloaded constant Reals :: 'a set is now
  6362 defined as range of_real; potential INCOMPATIBILITY.
  6363 
  6364 * Real: proper support for ML code generation, including 'quickcheck'.
  6365 Reals are implemented as arbitrary precision rationals.
  6366 
  6367 * Hyperreal: Several constants that previously worked only for the
  6368 reals have been generalized, so they now work over arbitrary vector
  6369 spaces. Type annotations may need to be added in some cases; potential
  6370 INCOMPATIBILITY.
  6371 
  6372   Infinitesimal  :: ('a::real_normed_vector) star set
  6373   HFinite        :: ('a::real_normed_vector) star set
  6374   HInfinite      :: ('a::real_normed_vector) star set
  6375   approx         :: ('a::real_normed_vector) star => 'a star => bool
  6376   monad          :: ('a::real_normed_vector) star => 'a star set
  6377   galaxy         :: ('a::real_normed_vector) star => 'a star set
  6378   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  6379   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  6380   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  6381   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  6382   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  6383   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  6384   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  6385   sgn            :: 'a::real_normed_vector => 'a
  6386   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  6387 
  6388 * Complex: Some complex-specific constants are now abbreviations for
  6389 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  6390 hnorm.  Other constants have been entirely removed in favor of the
  6391 polymorphic versions (INCOMPATIBILITY):
  6392 
  6393   approx        <-- capprox
  6394   HFinite       <-- CFinite
  6395   HInfinite     <-- CInfinite
  6396   Infinitesimal <-- CInfinitesimal
  6397   monad         <-- cmonad
  6398   galaxy        <-- cgalaxy
  6399   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  6400   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  6401   (ns)deriv     <-- (ns)cderiv
  6402 
  6403 
  6404 *** HOL-Algebra ***
  6405 
  6406 * Formalisation of ideals and the quotient construction over rings.
  6407 
  6408 * Order and lattice theory no longer based on records.
  6409 INCOMPATIBILITY.
  6410 
  6411 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  6412 greatest_closed.  INCOMPATIBILITY.
  6413 
  6414 * Method algebra is now set up via an attribute.  For examples see
  6415 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  6416 of algebraic structures.
  6417 
  6418 * Renamed theory CRing to Ring.
  6419 
  6420 
  6421 *** HOL-Nominal ***
  6422 
  6423 * Substantial, yet incomplete support for nominal datatypes (binding
  6424 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  6425 src/HOL/Nominal/Examples.  Prospective users should consult
  6426 http://isabelle.in.tum.de/nominal/
  6427 
  6428 
  6429 *** ML ***
  6430 
  6431 * ML basics: just one true type int, which coincides with IntInf.int
  6432 (even on SML/NJ).
  6433 
  6434 * ML within Isar: antiquotations allow to embed statically-checked
  6435 formal entities in the source, referring to the context available at
  6436 compile-time.  For example:
  6437 
  6438 ML {* @{sort "{zero,one}"} *}
  6439 ML {* @{typ "'a => 'b"} *}
  6440 ML {* @{term "%x. x"} *}
  6441 ML {* @{prop "x == y"} *}
  6442 ML {* @{ctyp "'a => 'b"} *}
  6443 ML {* @{cterm "%x. x"} *}
  6444 ML {* @{cprop "x == y"} *}
  6445 ML {* @{thm asm_rl} *}
  6446 ML {* @{thms asm_rl} *}
  6447 ML {* @{type_name c} *}
  6448 ML {* @{type_syntax c} *}
  6449 ML {* @{const_name c} *}
  6450 ML {* @{const_syntax c} *}
  6451 ML {* @{context} *}
  6452 ML {* @{theory} *}
  6453 ML {* @{theory Pure} *}
  6454 ML {* @{theory_ref} *}
  6455 ML {* @{theory_ref Pure} *}
  6456 ML {* @{simpset} *}
  6457 ML {* @{claset} *}
  6458 ML {* @{clasimpset} *}
  6459 
  6460 The same works for sources being ``used'' within an Isar context.
  6461 
  6462 * ML in Isar: improved error reporting; extra verbosity with
  6463 ML_Context.trace enabled.
  6464 
  6465 * Pure/General/table.ML: the join operations now works via exceptions
  6466 DUP/SAME instead of type option. This is simpler in simple cases, and
  6467 admits slightly more efficient complex applications.
  6468 
  6469 * Pure: 'advanced' translation functions (parse_translation etc.) now
  6470 use Context.generic instead of just theory.
  6471 
  6472 * Pure: datatype Context.generic joins theory/Proof.context and
  6473 provides some facilities for code that works in either kind of
  6474 context, notably GenericDataFun for uniform theory and proof data.
  6475 
  6476 * Pure: simplified internal attribute type, which is now always
  6477 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  6478 local (Proof.context) attributes have been discontinued, while
  6479 minimizing code duplication. Thm.rule_attribute and
  6480 Thm.declaration_attribute build canonical attributes; see also structure
  6481 Context for further operations on Context.generic, notably
  6482 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  6483 declarations and definitions.
  6484 
  6485 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  6486 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  6487 init only required for impure data. INCOMPATIBILITY: empty really need
  6488 to be empty (no dependencies on theory content!)
  6489 
  6490 * Pure/kernel: consts certification ignores sort constraints given in
  6491 signature declarations. (This information is not relevant to the
  6492 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  6493 potential INCOMPATIBILITY.
  6494 
  6495 * Pure: axiomatic type classes are now purely definitional, with
  6496 explicit proofs of class axioms and super class relations performed
  6497 internally. See Pure/axclass.ML for the main internal interfaces --
  6498 notably AxClass.define_class supercedes AxClass.add_axclass, and
  6499 AxClass.axiomatize_class/classrel/arity supersede
  6500 Sign.add_classes/classrel/arities.
  6501 
  6502 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  6503 global/local versions on theory vs. Proof.context have been
  6504 discontinued; Attrib.syntax and Method.syntax have been adapted
  6505 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  6506 attributes, methods, etc.
  6507 
  6508 * Pure: several functions of signature "... -> theory -> theory * ..."
  6509 have been reoriented to "... -> theory -> ... * theory" in order to
  6510 allow natural usage in combination with the ||>, ||>>, |-> and
  6511 fold_map combinators.
  6512 
  6513 * Pure: official theorem names (closed derivations) and additional
  6514 comments (tags) are now strictly separate.  Name hints -- which are
  6515 maintained as tags -- may be attached any time without affecting the
  6516 derivation.
  6517 
  6518 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  6519 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  6520 achieve the old behaviour.
  6521 
  6522 * Pure: the "Goal" constant is now called "prop", supporting a
  6523 slightly more general idea of ``protecting'' meta-level rule
  6524 statements.
  6525 
  6526 * Pure: Logic.(un)varify only works in a global context, which is now
  6527 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  6528 Logic.legacy_(un)varify as temporary workaround.
  6529 
  6530 * Pure: structure Name provides scalable operations for generating
  6531 internal variable names, notably Name.variants etc.  This replaces
  6532 some popular functions from term.ML:
  6533 
  6534   Term.variant		->  Name.variant
  6535   Term.variantlist	->  Name.variant_list
  6536   Term.invent_names	->  Name.invent_list
  6537 
  6538 Note that low-level renaming rarely occurs in new code -- operations
  6539 from structure Variable are used instead (see below).
  6540 
  6541 * Pure: structure Variable provides fundamental operations for proper
  6542 treatment of fixed/schematic variables in a context.  For example,
  6543 Variable.import introduces fixes for schematics of given facts and
  6544 Variable.export reverses the effect (up to renaming) -- this replaces
  6545 various freeze_thaw operations.
  6546 
  6547 * Pure: structure Goal provides simple interfaces for
  6548 init/conclude/finish and tactical prove operations (replacing former
  6549 Tactic.prove).  Goal.prove is the canonical way to prove results
  6550 within a given context; Goal.prove_global is a degraded version for
  6551 theory level goals, including a global Drule.standard.  Note that
  6552 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  6553 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  6554 in a locale context).
  6555 
  6556 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  6557 and type checking (Syntax.check_term etc.), with common combinations
  6558 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  6559 which are considered legacy and await removal.
  6560 
  6561 * Pure/Syntax: generic interfaces for type unchecking
  6562 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  6563 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  6564 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  6565 available for convenience, but refer to the very same operations using
  6566 a mere theory instead of a full context.
  6567 
  6568 * Isar: simplified treatment of user-level errors, using exception
  6569 ERROR of string uniformly.  Function error now merely raises ERROR,
  6570 without any side effect on output channels.  The Isar toplevel takes
  6571 care of proper display of ERROR exceptions.  ML code may use plain
  6572 handle/can/try; cat_error may be used to concatenate errors like this:
  6573 
  6574   ... handle ERROR msg => cat_error msg "..."
  6575 
  6576 Toplevel ML code (run directly or through the Isar toplevel) may be
  6577 embedded into the Isar toplevel with exception display/debug like
  6578 this:
  6579 
  6580   Isar.toplevel (fn () => ...)
  6581 
  6582 INCOMPATIBILITY, removed special transform_error facilities, removed
  6583 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  6584 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  6585 -- use plain ERROR instead.
  6586 
  6587 * Isar: theory setup now has type (theory -> theory), instead of a
  6588 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  6589 
  6590 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  6591 ProofContext.debug/verbose flags.
  6592 
  6593 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  6594 theory before entering a proof state.  Transactions now always see a
  6595 quasi-functional intermediate checkpoint, both in interactive and
  6596 batch mode.
  6597 
  6598 * Isar: simplified interfaces for outer syntax.  Renamed
  6599 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  6600 OuterSyntax.add_parsers -- this functionality is now included in
  6601 OuterSyntax.command etc.  INCOMPATIBILITY.
  6602 
  6603 * Simplifier: the simpset of a running simplification process now
  6604 contains a proof context (cf. Simplifier.the_context), which is the
  6605 very context that the initial simpset has been retrieved from (by
  6606 simpset_of/local_simpset_of).  Consequently, all plug-in components
  6607 (solver, looper etc.) may depend on arbitrary proof data.
  6608 
  6609 * Simplifier.inherit_context inherits the proof context (plus the
  6610 local bounds) of the current simplification process; any simproc
  6611 etc. that calls the Simplifier recursively should do this!  Removed
  6612 former Simplifier.inherit_bounds, which is already included here --
  6613 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  6614 specify an explicit context using Simplifier.context/theory_context.
  6615 
  6616 * Simplifier/Classical Reasoner: more abstract interfaces
  6617 change_simpset/claset for modifying the simpset/claset reference of a
  6618 theory; raw versions simpset/claset_ref etc. have been discontinued --
  6619 INCOMPATIBILITY.
  6620 
  6621 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  6622 "Trueprop" etc.
  6623 
  6624 
  6625 *** System ***
  6626 
  6627 * settings: the default heap location within ISABELLE_HOME_USER now
  6628 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  6629 Isabelle installations.
  6630 
  6631 * isabelle-process: option -S (secure mode) disables some critical
  6632 operations, notably runtime compilation and evaluation of ML source
  6633 code.
  6634 
  6635 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  6636 
  6637 * Support for parallel execution, using native multicore support of
  6638 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  6639 independent theories, according to the given theory header
  6640 specifications. The maximum number of worker threads is specified via
  6641 usedir option -M or the "max-threads" setting in Proof General. A
  6642 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  6643 to 6 on a 8-core machine.  User-code needs to observe certain
  6644 guidelines for thread-safe programming, see appendix A in the Isar
  6645 Implementation manual.
  6646 
  6647 
  6648 
  6649 New in Isabelle2005 (October 2005)
  6650 ----------------------------------
  6651 
  6652 *** General ***
  6653 
  6654 * Theory headers: the new header syntax for Isar theories is
  6655 
  6656   theory <name>
  6657   imports <theory1> ... <theoryN>
  6658   uses <file1> ... <fileM>
  6659   begin
  6660 
  6661 where the 'uses' part is optional.  The previous syntax
  6662 
  6663   theory <name> = <theory1> + ... + <theoryN>:
  6664 
  6665 will disappear in the next release.  Use isatool fixheaders to convert
  6666 existing theory files.  Note that there is no change in ancient
  6667 non-Isar theories now, but these will disappear soon.
  6668 
  6669 * Theory loader: parent theories can now also be referred to via
  6670 relative and absolute paths.
  6671 
  6672 * Command 'find_theorems' searches for a list of criteria instead of a
  6673 list of constants. Known criteria are: intro, elim, dest, name:string,
  6674 simp:term, and any term. Criteria can be preceded by '-' to select
  6675 theorems that do not match. Intro, elim, dest select theorems that
  6676 match the current goal, name:s selects theorems whose fully qualified
  6677 name contain s, and simp:term selects all simplification rules whose
  6678 lhs match term.  Any other term is interpreted as pattern and selects
  6679 all theorems matching the pattern. Available in ProofGeneral under
  6680 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  6681 
  6682   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  6683 
  6684 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  6685 matching the current goal as introduction rule and not having "HOL."
  6686 in their name (i.e. not being defined in theory HOL).
  6687 
  6688 * Command 'thms_containing' has been discontinued in favour of
  6689 'find_theorems'; INCOMPATIBILITY.
  6690 
  6691 * Communication with Proof General is now 8bit clean, which means that
  6692 Unicode text in UTF-8 encoding may be used within theory texts (both
  6693 formal and informal parts).  Cf. option -U of the Isabelle Proof
  6694 General interface.  Here are some simple examples (cf. src/HOL/ex):
  6695 
  6696   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  6697   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  6698 
  6699 * Improved efficiency of the Simplifier and, to a lesser degree, the
  6700 Classical Reasoner.  Typical big applications run around 2 times
  6701 faster.
  6702 
  6703 
  6704 *** Document preparation ***
  6705 
  6706 * Commands 'display_drafts' and 'print_drafts' perform simple output
  6707 of raw sources.  Only those symbols that do not require additional
  6708 LaTeX packages (depending on comments in isabellesym.sty) are
  6709 displayed properly, everything else is left verbatim.  isatool display
  6710 and isatool print are used as front ends (these are subject to the
  6711 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  6712 
  6713 * Command tags control specific markup of certain regions of text,
  6714 notably folding and hiding.  Predefined tags include "theory" (for
  6715 theory begin and end), "proof" for proof commands, and "ML" for
  6716 commands involving ML code; the additional tags "visible" and
  6717 "invisible" are unused by default.  Users may give explicit tag
  6718 specifications in the text, e.g. ''by %invisible (auto)''.  The
  6719 interpretation of tags is determined by the LaTeX job during document
  6720 preparation: see option -V of isatool usedir, or options -n and -t of
  6721 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  6722 \isadroptag.
  6723 
  6724 Several document versions may be produced at the same time via isatool
  6725 usedir (the generated index.html will link all of them).  Typical
  6726 specifications include ''-V document=theory,proof,ML'' to present
  6727 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  6728 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  6729 these parts without any formal replacement text.  The Isabelle site
  6730 default settings produce ''document'' and ''outline'' versions as
  6731 specified above.
  6732 
  6733 * Several new antiquotations:
  6734 
  6735   @{term_type term} prints a term with its type annotated;
  6736 
  6737   @{typeof term} prints the type of a term;
  6738 
  6739   @{const const} is the same as @{term const}, but checks that the
  6740   argument is a known logical constant;
  6741 
  6742   @{term_style style term} and @{thm_style style thm} print a term or
  6743   theorem applying a "style" to it
  6744 
  6745   @{ML text}
  6746 
  6747 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  6748 definitions, equations, inequations etc., 'concl' printing only the
  6749 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  6750 to print the specified premise.  TermStyle.add_style provides an ML
  6751 interface for introducing further styles.  See also the "LaTeX Sugar"
  6752 document practical applications.  The ML antiquotation prints
  6753 type-checked ML expressions verbatim.
  6754 
  6755 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  6756 and 'text' support optional locale specification '(in loc)', which
  6757 specifies the default context for interpreting antiquotations.  For
  6758 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  6759 
  6760 * Option 'locale=NAME' of antiquotations specifies an alternative
  6761 context interpreting the subsequent argument.  For example: @{thm
  6762 [locale=lattice] inf_assoc}.
  6763 
  6764 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  6765 a proof context.
  6766 
  6767 * Proper output of antiquotations for theory commands involving a
  6768 proof context (such as 'locale' or 'theorem (in loc) ...').
  6769 
  6770 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  6771 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  6772 
  6773 * isatool usedir: new option -C (default true) controls whether option
  6774 -D should include a copy of the original document directory; -C false
  6775 prevents unwanted effects such as copying of administrative CVS data.
  6776 
  6777 
  6778 *** Pure ***
  6779 
  6780 * Considerably improved version of 'constdefs' command.  Now performs
  6781 automatic type-inference of declared constants; additional support for
  6782 local structure declarations (cf. locales and HOL records), see also
  6783 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  6784 sequential dependencies of definitions within a single 'constdefs'
  6785 section; moreover, the declared name needs to be an identifier.  If
  6786 all fails, consider to fall back on 'consts' and 'defs' separately.
  6787 
  6788 * Improved indexed syntax and implicit structures.  First of all,
  6789 indexed syntax provides a notational device for subscripted
  6790 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  6791 expressions.  Secondly, in a local context with structure
  6792 declarations, number indexes \<^sub>n or the empty index (default
  6793 number 1) refer to a certain fixed variable implicitly; option
  6794 show_structs controls printing of implicit structures.  Typical
  6795 applications of these concepts involve record types and locales.
  6796 
  6797 * New command 'no_syntax' removes grammar declarations (and
  6798 translations) resulting from the given syntax specification, which is
  6799 interpreted in the same manner as for the 'syntax' command.
  6800 
  6801 * 'Advanced' translation functions (parse_translation etc.) may depend
  6802 on the signature of the theory context being presently used for
  6803 parsing/printing, see also isar-ref manual.
  6804 
  6805 * Improved 'oracle' command provides a type-safe interface to turn an
  6806 ML expression of type theory -> T -> term into a primitive rule of
  6807 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  6808 is already included here); see also FOL/ex/IffExample.thy;
  6809 INCOMPATIBILITY.
  6810 
  6811 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  6812 before); "cI" is no longer bound, use "c.intro" instead.
  6813 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  6814 axclasses vs. locales.
  6815 
  6816 * Improved internal renaming of symbolic identifiers -- attach primes
  6817 instead of base 26 numbers.
  6818 
  6819 * New flag show_question_marks controls printing of leading question
  6820 marks in schematic variable names.
  6821 
  6822 * In schematic variable names, *any* symbol following \<^isub> or
  6823 \<^isup> is now treated as part of the base name.  For example, the
  6824 following works without printing of awkward ".0" indexes:
  6825 
  6826   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  6827     by simp
  6828 
  6829 * Inner syntax includes (*(*nested*) comments*).
  6830 
  6831 * Pretty printer now supports unbreakable blocks, specified in mixfix
  6832 annotations as "(00...)".
  6833 
  6834 * Clear separation of logical types and nonterminals, where the latter
  6835 may only occur in 'syntax' specifications or type abbreviations.
  6836 Before that distinction was only partially implemented via type class
  6837 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  6838 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  6839 exotic syntax specifications may require further adaption
  6840 (e.g. Cube/Cube.thy).
  6841 
  6842 * Removed obsolete type class "logic", use the top sort {} instead.
  6843 Note that non-logical types should be declared as 'nonterminals'
  6844 rather than 'types'.  INCOMPATIBILITY for new object-logic
  6845 specifications.
  6846 
  6847 * Attributes 'induct' and 'cases': type or set names may now be
  6848 locally fixed variables as well.
  6849 
  6850 * Simplifier: can now control the depth to which conditional rewriting
  6851 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  6852 Limit.
  6853 
  6854 * Simplifier: simplification procedures may now take the current
  6855 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  6856 interface), which is very useful for calling the Simplifier
  6857 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  6858 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  6859 low-level mk_simproc no longer applies Logic.varify internally, to
  6860 allow for use in a context of fixed variables.
  6861 
  6862 * thin_tac now works even if the assumption being deleted contains !!
  6863 or ==>.  More generally, erule now works even if the major premise of
  6864 the elimination rule contains !! or ==>.
  6865 
  6866 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  6867 
  6868 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  6869 from Pure, which contains all common declarations already.  Both
  6870 theories are defined via plain Isabelle/Isar .thy files.
  6871 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  6872 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  6873 use isatool fixcpure to adapt your theory and ML sources.
  6874 
  6875 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  6876 selections of theorems in named facts via index ranges.
  6877 
  6878 * 'print_theorems': in theory mode, really print the difference
  6879 wrt. the last state (works for interactive theory development only),
  6880 in proof mode print all local facts (cf. 'print_facts');
  6881 
  6882 * 'hide': option '(open)' hides only base names.
  6883 
  6884 * More efficient treatment of intermediate checkpoints in interactive
  6885 theory development.
  6886 
  6887 * Code generator is now invoked via code_module (incremental code
  6888 generation) and code_library (modular code generation, ML structures
  6889 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  6890 must be quoted when used as identifiers.
  6891 
  6892 * New 'value' command for reading, evaluating and printing terms using
  6893 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  6894 quoted when used as identifier.
  6895 
  6896 
  6897 *** Locales ***
  6898 
  6899 * New commands for the interpretation of locale expressions in
  6900 theories (1), locales (2) and proof contexts (3).  These generate
  6901 proof obligations from the expression specification.  After the
  6902 obligations have been discharged, theorems of the expression are added
  6903 to the theory, target locale or proof context.  The synopsis of the
  6904 commands is a follows:
  6905 
  6906   (1) interpretation expr inst
  6907   (2) interpretation target < expr
  6908   (3) interpret expr inst
  6909 
  6910 Interpretation in theories and proof contexts require a parameter
  6911 instantiation of terms from the current context.  This is applied to
  6912 specifications and theorems of the interpreted expression.
  6913 Interpretation in locales only permits parameter renaming through the
  6914 locale expression.  Interpretation is smart in that interpretations
  6915 that are active already do not occur in proof obligations, neither are
  6916 instantiated theorems stored in duplicate.  Use 'print_interps' to
  6917 inspect active interpretations of a particular locale.  For details,
  6918 see the Isar Reference manual.  Examples can be found in
  6919 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  6920 
  6921 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  6922 'interpret' instead.
  6923 
  6924 * New context element 'constrains' for adding type constraints to
  6925 parameters.
  6926 
  6927 * Context expressions: renaming of parameters with syntax
  6928 redeclaration.
  6929 
  6930 * Locale declaration: 'includes' disallowed.
  6931 
  6932 * Proper static binding of attribute syntax -- i.e. types / terms /
  6933 facts mentioned as arguments are always those of the locale definition
  6934 context, independently of the context of later invocations.  Moreover,
  6935 locale operations (renaming and type / term instantiation) are applied
  6936 to attribute arguments as expected.
  6937 
  6938 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  6939 actual attributes; rare situations may require Attrib.attribute to
  6940 embed those attributes into Attrib.src that lack concrete syntax.
  6941 Attribute implementations need to cooperate properly with the static
  6942 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  6943 Attrib.XXX_thm etc. already do the right thing without further
  6944 intervention.  Only unusual applications -- such as "where" or "of"
  6945 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  6946 on the context and the facts involved -- may have to assign parsed
  6947 values to argument tokens explicitly.
  6948 
  6949 * Changed parameter management in theorem generation for long goal
  6950 statements with 'includes'.  INCOMPATIBILITY: produces a different
  6951 theorem statement in rare situations.
  6952 
  6953 * Locale inspection command 'print_locale' omits notes elements.  Use
  6954 'print_locale!' to have them included in the output.
  6955 
  6956 
  6957 *** Provers ***
  6958 
  6959 * Provers/hypsubst.ML: improved version of the subst method, for
  6960 single-step rewriting: it now works in bound variable contexts. New is
  6961 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  6962 rewrite a different subterm than the original subst method, which is
  6963 still available as 'simplesubst'.
  6964 
  6965 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  6966 and quasi orders.
  6967 
  6968 * Provers/trancl.ML: new transitivity reasoner for transitive and
  6969 reflexive-transitive closure of relations.
  6970 
  6971 * Provers/blast.ML: new reference depth_limit to make blast's depth
  6972 limit (previously hard-coded with a value of 20) user-definable.
  6973 
  6974 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  6975 is peformed already.  Object-logics merely need to finish their
  6976 initial simpset configuration as before.  INCOMPATIBILITY.
  6977 
  6978 
  6979 *** HOL ***
  6980 
  6981 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  6982 
  6983   syntax (epsilon)
  6984     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  6985 
  6986 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  6987 and x-symbol; use option '-m epsilon' to get it actually printed.
  6988 Moreover, the mathematically important symbolic identifier \<epsilon>
  6989 becomes available as variable, constant etc.  INCOMPATIBILITY,
  6990 
  6991 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  6992 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  6993 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  6994 support corresponding Isar calculations.
  6995 
  6996 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  6997 instead of ":".
  6998 
  6999 * theory SetInterval: changed the syntax for open intervals:
  7000 
  7001   Old       New
  7002   {..n(}    {..<n}
  7003   {)n..}    {n<..}
  7004   {m..n(}   {m..<n}
  7005   {)m..n}   {m<..n}
  7006   {)m..n(}  {m<..<n}
  7007 
  7008 The old syntax is still supported but will disappear in the next
  7009 release.  For conversion use the following Emacs search and replace
  7010 patterns (these are not perfect but work quite well):
  7011 
  7012   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  7013   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  7014 
  7015 * Theory Commutative_Ring (in Library): method comm_ring for proving
  7016 equalities in commutative rings; method 'algebra' provides a generic
  7017 interface.
  7018 
  7019 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  7020 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  7021 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  7022 be a tuple pattern.
  7023 
  7024 Some new syntax forms are available:
  7025 
  7026   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  7027   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  7028   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  7029   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  7030 
  7031 The latter form "\<Sum>x < k. e" used to be based on a separate
  7032 function "Summation", which has been discontinued.
  7033 
  7034 * theory Finite_Set: in structured induction proofs, the insert case
  7035 is now 'case (insert x F)' instead of the old counterintuitive 'case
  7036 (insert F x)'.
  7037 
  7038 * The 'refute' command has been extended to support a much larger
  7039 fragment of HOL, including axiomatic type classes, constdefs and
  7040 typedefs, inductive datatypes and recursion.
  7041 
  7042 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  7043 Requires zChaff with proof generation to be installed.  See
  7044 HOL/ex/SAT_Examples.thy for examples.
  7045 
  7046 * Datatype induction via method 'induct' now preserves the name of the
  7047 induction variable. For example, when proving P(xs::'a list) by
  7048 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  7049 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  7050 in unstructured proof scripts.
  7051 
  7052 * Reworked implementation of records.  Improved scalability for
  7053 records with many fields, avoiding performance problems for type
  7054 inference. Records are no longer composed of nested field types, but
  7055 of nested extension types. Therefore the record type only grows linear
  7056 in the number of extensions and not in the number of fields.  The
  7057 top-level (users) view on records is preserved.  Potential
  7058 INCOMPATIBILITY only in strange cases, where the theory depends on the
  7059 old record representation. The type generated for a record is called
  7060 <record_name>_ext_type.
  7061 
  7062 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  7063 proofs triggered by a record definition or a simproc (if
  7064 quick_and_dirty is enabled).  Definitions of large records can take
  7065 quite long.
  7066 
  7067 New simproc record_upd_simproc for simplification of multiple record
  7068 updates enabled by default.  Moreover, trivial updates are also
  7069 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  7070 occasionally, since simplification is more powerful by default.
  7071 
  7072 * typedef: proper support for polymorphic sets, which contain extra
  7073 type-variables in the term.
  7074 
  7075 * Simplifier: automatically reasons about transitivity chains
  7076 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  7077 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  7078 old proofs break occasionally as simplification may now solve more
  7079 goals than previously.
  7080 
  7081 * Simplifier: converts x <= y into x = y if assumption y <= x is
  7082 present.  Works for all partial orders (class "order"), in particular
  7083 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  7084 just like y <= x.
  7085 
  7086 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  7087 bound variable or a constant then the let is unfolded.  Otherwise
  7088 first a is simplified to b, and then f b is simplified to g. If
  7089 possible we abstract b from g arriving at "let x = b in h x",
  7090 otherwise we unfold the let and arrive at g.  The simproc can be
  7091 enabled/disabled by the reference use_let_simproc.  Potential
  7092 INCOMPATIBILITY since simplification is more powerful by default.
  7093 
  7094 * Classical reasoning: the meson method now accepts theorems as arguments.
  7095 
  7096 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  7097 jobs to provide advice on the provability of subgoals.
  7098 
  7099 * Theory OrderedGroup and Ring_and_Field: various additions and
  7100 improvements to faciliate calculations involving equalities and
  7101 inequalities.
  7102 
  7103 The following theorems have been eliminated or modified
  7104 (INCOMPATIBILITY):
  7105 
  7106   abs_eq             now named abs_of_nonneg
  7107   abs_of_ge_0        now named abs_of_nonneg
  7108   abs_minus_eq       now named abs_of_nonpos
  7109   imp_abs_id         now named abs_of_nonneg
  7110   imp_abs_neg_id     now named abs_of_nonpos
  7111   mult_pos           now named mult_pos_pos
  7112   mult_pos_le        now named mult_nonneg_nonneg
  7113   mult_pos_neg_le    now named mult_nonneg_nonpos
  7114   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  7115   mult_neg           now named mult_neg_neg
  7116   mult_neg_le        now named mult_nonpos_nonpos
  7117 
  7118 * The following lemmas in Ring_and_Field have been added to the simplifier:
  7119      
  7120      zero_le_square
  7121      not_square_less_zero 
  7122 
  7123   The following lemmas have been deleted from Real/RealPow:
  7124   
  7125      realpow_zero_zero
  7126      realpow_two
  7127      realpow_less
  7128      zero_le_power
  7129      realpow_two_le
  7130      abs_realpow_two
  7131      realpow_two_abs     
  7132 
  7133 * Theory Parity: added rules for simplifying exponents.
  7134 
  7135 * Theory List:
  7136 
  7137 The following theorems have been eliminated or modified
  7138 (INCOMPATIBILITY):
  7139 
  7140   list_all_Nil       now named list_all.simps(1)
  7141   list_all_Cons      now named list_all.simps(2)
  7142   list_all_conv      now named list_all_iff
  7143   set_mem_eq         now named mem_iff
  7144 
  7145 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  7146 asymptotic "big O" calculations.  See the notes in BigO.thy.
  7147 
  7148 
  7149 *** HOL-Complex ***
  7150 
  7151 * Theory RealDef: better support for embedding natural numbers and
  7152 integers in the reals.
  7153 
  7154 The following theorems have been eliminated or modified
  7155 (INCOMPATIBILITY):
  7156 
  7157   exp_ge_add_one_self  now requires no hypotheses
  7158   real_of_int_add      reversed direction of equality (use [symmetric])
  7159   real_of_int_minus    reversed direction of equality (use [symmetric])
  7160   real_of_int_diff     reversed direction of equality (use [symmetric])
  7161   real_of_int_mult     reversed direction of equality (use [symmetric])
  7162 
  7163 * Theory RComplete: expanded support for floor and ceiling functions.
  7164 
  7165 * Theory Ln is new, with properties of the natural logarithm
  7166 
  7167 * Hyperreal: There is a new type constructor "star" for making
  7168 nonstandard types.  The old type names are now type synonyms:
  7169 
  7170   hypreal = real star
  7171   hypnat = nat star
  7172   hcomplex = complex star
  7173 
  7174 * Hyperreal: Many groups of similarly-defined constants have been
  7175 replaced by polymorphic versions (INCOMPATIBILITY):
  7176 
  7177   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  7178 
  7179   starset      <-- starsetNat, starsetC
  7180   *s*          <-- *sNat*, *sc*
  7181   starset_n    <-- starsetNat_n, starsetC_n
  7182   *sn*         <-- *sNatn*, *scn*
  7183   InternalSets <-- InternalNatSets, InternalCSets
  7184 
  7185   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  7186   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  7187   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  7188   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  7189   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  7190 
  7191 * Hyperreal: Many type-specific theorems have been removed in favor of
  7192 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  7193 
  7194   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  7195   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  7196   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  7197   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  7198   right_minus <-- hypreal_add_minus
  7199   left_minus <-- {hypreal,hcomplex}_add_minus_left
  7200   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  7201   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  7202   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  7203   mult_1_right <-- hcomplex_mult_one_right
  7204   mult_zero_left <-- hcomplex_mult_zero_left
  7205   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  7206   right_distrib <-- hypnat_add_mult_distrib2
  7207   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  7208   right_inverse <-- hypreal_mult_inverse
  7209   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  7210   order_refl <-- {hypreal,hypnat}_le_refl
  7211   order_trans <-- {hypreal,hypnat}_le_trans
  7212   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  7213   order_less_le <-- {hypreal,hypnat}_less_le
  7214   linorder_linear <-- {hypreal,hypnat}_le_linear
  7215   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  7216   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  7217   add_nonneg_nonneg <-- hypreal_le_add_order
  7218 
  7219 * Hyperreal: Separate theorems having to do with type-specific
  7220 versions of constants have been merged into theorems that apply to the
  7221 new polymorphic constants (INCOMPATIBILITY):
  7222 
  7223   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  7224   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  7225   STAR_Un <-- {STAR,NatStar,STARC}_Un
  7226   STAR_Int <-- {STAR,NatStar,STARC}_Int
  7227   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  7228   STAR_subset <-- {STAR,NatStar,STARC}_subset
  7229   STAR_mem <-- {STAR,NatStar,STARC}_mem
  7230   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  7231   STAR_diff <-- {STAR,STARC}_diff
  7232   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  7233     STARC_hcomplex_of_complex}_image_subset
  7234   starset_n_Un <-- starset{Nat,C}_n_Un
  7235   starset_n_Int <-- starset{Nat,C}_n_Int
  7236   starset_n_Compl <-- starset{Nat,C}_n_Compl
  7237   starset_n_diff <-- starset{Nat,C}_n_diff
  7238   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  7239   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  7240   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  7241   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  7242   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  7243   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  7244   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  7245   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  7246   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  7247   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  7248   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  7249   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  7250   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  7251   starfun_diff <-- starfun{C,RC,CR}_diff
  7252   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  7253   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  7254   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  7255   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  7256   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  7257   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  7258   starfun_Id <-- starfunC_Id
  7259   starfun_approx <-- starfun{Nat,CR}_approx
  7260   starfun_capprox <-- starfun{C,RC}_capprox
  7261   starfun_abs <-- starfunNat_rabs
  7262   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  7263   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  7264   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  7265   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  7266   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  7267   starfun_add_approx <-- starfunCR_add_approx
  7268   starfun_inverse_inverse <-- starfunC_inverse_inverse
  7269   starfun_divide <-- starfun{C,CR,RC}_divide
  7270   starfun_n <-- starfun{Nat,C}_n
  7271   starfun_n_mult <-- starfun{Nat,C}_n_mult
  7272   starfun_n_add <-- starfun{Nat,C}_n_add
  7273   starfun_n_add_minus <-- starfunNat_n_add_minus
  7274   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  7275   starfun_n_minus <-- starfun{Nat,C}_n_minus
  7276   starfun_n_eq <-- starfun{Nat,C}_n_eq
  7277 
  7278   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  7279   star_n_minus <-- {hypreal,hcomplex}_minus
  7280   star_n_diff <-- {hypreal,hcomplex}_diff
  7281   star_n_mult <-- {hypreal,hcomplex}_mult
  7282   star_n_inverse <-- {hypreal,hcomplex}_inverse
  7283   star_n_le <-- {hypreal,hypnat}_le
  7284   star_n_less <-- {hypreal,hypnat}_less
  7285   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  7286   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  7287   star_n_abs <-- hypreal_hrabs
  7288   star_n_divide <-- hcomplex_divide
  7289 
  7290   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  7291   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  7292   star_of_diff <-- hypreal_of_real_diff
  7293   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  7294   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  7295   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  7296   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  7297   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  7298   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  7299   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  7300   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  7301   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  7302   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  7303   star_of_number_of <-- {hypreal,hcomplex}_number_of
  7304   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  7305   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  7306   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  7307   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  7308   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  7309   star_of_power <-- hypreal_of_real_power
  7310   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  7311 
  7312 * Hyperreal: new method "transfer" that implements the transfer
  7313 principle of nonstandard analysis. With a subgoal that mentions
  7314 nonstandard types like "'a star", the command "apply transfer"
  7315 replaces it with an equivalent one that mentions only standard types.
  7316 To be successful, all free variables must have standard types; non-
  7317 standard variables must have explicit universal quantifiers.
  7318 
  7319 * Hyperreal: A theory of Taylor series.
  7320 
  7321 
  7322 *** HOLCF ***
  7323 
  7324 * Discontinued special version of 'constdefs' (which used to support
  7325 continuous functions) in favor of the general Pure one with full
  7326 type-inference.
  7327 
  7328 * New simplification procedure for solving continuity conditions; it
  7329 is much faster on terms with many nested lambda abstractions (cubic
  7330 instead of exponential time).
  7331 
  7332 * New syntax for domain package: selector names are now optional.
  7333 Parentheses should be omitted unless argument is lazy, for example:
  7334 
  7335   domain 'a stream = cons "'a" (lazy "'a stream")
  7336 
  7337 * New command 'fixrec' for defining recursive functions with pattern
  7338 matching; defining multiple functions with mutual recursion is also
  7339 supported.  Patterns may include the constants cpair, spair, up, sinl,
  7340 sinr, or any data constructor defined by the domain package. The given
  7341 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  7342 syntax and examples.
  7343 
  7344 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  7345 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  7346 but the proof obligation additionally includes an admissibility
  7347 requirement. The packages generate instances of class cpo or pcpo,
  7348 with continuity and strictness theorems for Rep and Abs.
  7349 
  7350 * HOLCF: Many theorems have been renamed according to a more standard naming
  7351 scheme (INCOMPATIBILITY):
  7352 
  7353   foo_inject:  "foo$x = foo$y ==> x = y"
  7354   foo_eq:      "(foo$x = foo$y) = (x = y)"
  7355   foo_less:    "(foo$x << foo$y) = (x << y)"
  7356   foo_strict:  "foo$UU = UU"
  7357   foo_defined: "... ==> foo$x ~= UU"
  7358   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  7359 
  7360 
  7361 *** ZF ***
  7362 
  7363 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  7364 including the First Isomorphism Theorem (on quotienting by the kernel
  7365 of a homomorphism).
  7366 
  7367 * ZF/Simplifier: install second copy of type solver that actually
  7368 makes use of TC rules declared to Isar proof contexts (or locales);
  7369 the old version is still required for ML proof scripts.
  7370 
  7371 
  7372 *** Cube ***
  7373 
  7374 * Converted to Isar theory format; use locales instead of axiomatic
  7375 theories.
  7376 
  7377 
  7378 *** ML ***
  7379 
  7380 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  7381 for ||>, ||>>, |>>,
  7382 
  7383 * Pure/library.ML no longer defines its own option datatype, but uses
  7384 that of the SML basis, which has constructors NONE and SOME instead of
  7385 None and Some, as well as exception Option.Option instead of OPTION.
  7386 The functions the, if_none, is_some, is_none have been adapted
  7387 accordingly, while Option.map replaces apsome.
  7388 
  7389 * Pure/library.ML: the exception LIST has been given up in favour of
  7390 the standard exceptions Empty and Subscript, as well as
  7391 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  7392 superceded by the standard hd and tl functions etc.
  7393 
  7394 A number of basic list functions are no longer exported to the ML
  7395 toplevel, as they are variants of predefined functions.  The following
  7396 suggests how one can translate existing code:
  7397 
  7398     rev_append xs ys = List.revAppend (xs, ys)
  7399     nth_elem (i, xs) = List.nth (xs, i)
  7400     last_elem xs = List.last xs
  7401     flat xss = List.concat xss
  7402     seq fs = List.app fs
  7403     partition P xs = List.partition P xs
  7404     mapfilter f xs = List.mapPartial f xs
  7405 
  7406 * Pure/library.ML: several combinators for linear functional
  7407 transformations, notably reverse application and composition:
  7408 
  7409   x |> f                f #> g
  7410   (x, y) |-> f          f #-> g
  7411 
  7412 * Pure/library.ML: introduced/changed precedence of infix operators:
  7413 
  7414   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  7415   infix 2 ?;
  7416   infix 3 o oo ooo oooo;
  7417   infix 4 ~~ upto downto;
  7418 
  7419 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  7420 infix operators.
  7421 
  7422 * Pure/library.ML: natural list combinators fold, fold_rev, and
  7423 fold_map support linear functional transformations and nesting.  For
  7424 example:
  7425 
  7426   fold f [x1, ..., xN] y =
  7427     y |> f x1 |> ... |> f xN
  7428 
  7429   (fold o fold) f [xs1, ..., xsN] y =
  7430     y |> fold f xs1 |> ... |> fold f xsN
  7431 
  7432   fold f [x1, ..., xN] =
  7433     f x1 #> ... #> f xN
  7434 
  7435   (fold o fold) f [xs1, ..., xsN] =
  7436     fold f xs1 #> ... #> fold f xsN
  7437 
  7438 * Pure/library.ML: the following selectors on type 'a option are
  7439 available:
  7440 
  7441   the:               'a option -> 'a  (*partial*)
  7442   these:             'a option -> 'a  where 'a = 'b list
  7443   the_default: 'a -> 'a option -> 'a
  7444   the_list:          'a option -> 'a list
  7445 
  7446 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  7447 basic operations for association lists, following natural argument
  7448 order; moreover the explicit equality predicate passed here avoids
  7449 potentially expensive polymorphic runtime equality checks.
  7450 The old functions may be expressed as follows:
  7451 
  7452   assoc = uncurry (AList.lookup (op =))
  7453   assocs = these oo AList.lookup (op =)
  7454   overwrite = uncurry (AList.update (op =)) o swap
  7455 
  7456 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  7457 
  7458   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  7459   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  7460 
  7461 replacing make_keylist and keyfilter (occassionally used)
  7462 Naive rewrites:
  7463 
  7464   make_keylist = AList.make
  7465   keyfilter = AList.find (op =)
  7466 
  7467 * eq_fst and eq_snd now take explicit equality parameter, thus
  7468   avoiding eqtypes. Naive rewrites:
  7469 
  7470     eq_fst = eq_fst (op =)
  7471     eq_snd = eq_snd (op =)
  7472 
  7473 * Removed deprecated apl and apr (rarely used).
  7474   Naive rewrites:
  7475 
  7476     apl (n, op) =>>= curry op n
  7477     apr (op, m) =>>= fn n => op (n, m)
  7478 
  7479 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  7480 provides a reasonably efficient light-weight implementation of sets as
  7481 lists.
  7482 
  7483 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  7484 few new operations; existing lookup and update are now curried to
  7485 follow natural argument order (for use with fold etc.);
  7486 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  7487 
  7488 * Pure/General: output via the Isabelle channels of
  7489 writeln/warning/error etc. is now passed through Output.output, with a
  7490 hook for arbitrary transformations depending on the print_mode
  7491 (cf. Output.add_mode -- the first active mode that provides a output
  7492 function wins).  Already formatted output may be embedded into further
  7493 text via Output.raw; the result of Pretty.string_of/str_of and derived
  7494 functions (string_of_term/cterm/thm etc.) is already marked raw to
  7495 accommodate easy composition of diagnostic messages etc.  Programmers
  7496 rarely need to care about Output.output or Output.raw at all, with
  7497 some notable exceptions: Output.output is required when bypassing the
  7498 standard channels (writeln etc.), or in token translations to produce
  7499 properly formatted results; Output.raw is required when capturing
  7500 already output material that will eventually be presented to the user
  7501 a second time.  For the default print mode, both Output.output and
  7502 Output.raw have no effect.
  7503 
  7504 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  7505 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  7506 cumulative results are displayed at the end of a batch session.
  7507 
  7508 * Pure/General: File.sysify_path and File.quote_sysify path have been
  7509 replaced by File.platform_path and File.shell_path (with appropriate
  7510 hooks).  This provides a clean interface for unusual systems where the
  7511 internal and external process view of file names are different.
  7512 
  7513 * Pure: more efficient orders for basic syntactic entities: added
  7514 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  7515 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  7516 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  7517 orders now -- potential INCOMPATIBILITY for code that depends on a
  7518 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  7519 Library.sort_strings on result).
  7520 
  7521 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  7522 fold_types traverse types/terms from left to right, observing natural
  7523 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  7524 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  7525 
  7526 * Pure: name spaces have been refined, with significant changes of the
  7527 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  7528 to extern(_table).  The plain name entry path is superceded by a
  7529 general 'naming' context, which also includes the 'policy' to produce
  7530 a fully qualified name and external accesses of a fully qualified
  7531 name; NameSpace.extend is superceded by context dependent
  7532 Sign.declare_name.  Several theory and proof context operations modify
  7533 the naming context.  Especially note Theory.restore_naming and
  7534 ProofContext.restore_naming to get back to a sane state; note that
  7535 Theory.add_path is no longer sufficient to recover from
  7536 Theory.absolute_path in particular.
  7537 
  7538 * Pure: new flags short_names (default false) and unique_names
  7539 (default true) for controlling output of qualified names.  If
  7540 short_names is set, names are printed unqualified.  If unique_names is
  7541 reset, the name prefix is reduced to the minimum required to achieve
  7542 the original result when interning again, even if there is an overlap
  7543 with earlier declarations.
  7544 
  7545 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  7546 now 'extend', and 'merge' gets an additional Pretty.pp argument
  7547 (useful for printing error messages).  INCOMPATIBILITY.
  7548 
  7549 * Pure: major reorganization of the theory context.  Type Sign.sg and
  7550 Theory.theory are now identified, referring to the universal
  7551 Context.theory (see Pure/context.ML).  Actual signature and theory
  7552 content is managed as theory data.  The old code and interfaces were
  7553 spread over many files and structures; the new arrangement introduces
  7554 considerable INCOMPATIBILITY to gain more clarity:
  7555 
  7556   Context -- theory management operations (name, identity, inclusion,
  7557     parents, ancestors, merge, etc.), plus generic theory data;
  7558 
  7559   Sign -- logical signature and syntax operations (declaring consts,
  7560     types, etc.), plus certify/read for common entities;
  7561 
  7562   Theory -- logical theory operations (stating axioms, definitions,
  7563     oracles), plus a copy of logical signature operations (consts,
  7564     types, etc.); also a few basic management operations (Theory.copy,
  7565     Theory.merge, etc.)
  7566 
  7567 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  7568 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  7569 for convenience -- they merely return the theory.
  7570 
  7571 * Pure: type Type.tsig is superceded by theory in most interfaces.
  7572 
  7573 * Pure: the Isar proof context type is already defined early in Pure
  7574 as Context.proof (note that ProofContext.context and Proof.context are
  7575 aliases, where the latter is the preferred name).  This enables other
  7576 Isabelle components to refer to that type even before Isar is present.
  7577 
  7578 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  7579 typeK, constK, axiomK, oracleK), but provide explicit operations for
  7580 any of these kinds.  For example, Sign.intern typeK is now
  7581 Sign.intern_type, Theory.hide_space Sign.typeK is now
  7582 Theory.hide_types.  Also note that former
  7583 Theory.hide_classes/types/consts are now
  7584 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  7585 internalize their arguments!  INCOMPATIBILITY.
  7586 
  7587 * Pure: get_thm interface (of PureThy and ProofContext) expects
  7588 datatype thmref (with constructors Name and NameSelection) instead of
  7589 plain string -- INCOMPATIBILITY;
  7590 
  7591 * Pure: cases produced by proof methods specify options, where NONE
  7592 means to remove case bindings -- INCOMPATIBILITY in
  7593 (RAW_)METHOD_CASES.
  7594 
  7595 * Pure: the following operations retrieve axioms or theorems from a
  7596 theory node or theory hierarchy, respectively:
  7597 
  7598   Theory.axioms_of: theory -> (string * term) list
  7599   Theory.all_axioms_of: theory -> (string * term) list
  7600   PureThy.thms_of: theory -> (string * thm) list
  7601   PureThy.all_thms_of: theory -> (string * thm) list
  7602 
  7603 * Pure: print_tac now outputs the goal through the trace channel.
  7604 
  7605 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  7606 Reference Toplevel.debug (default false) controls detailed printing
  7607 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  7608 controls execution profiling -- set to 1 for time and 2 for space
  7609 (both increase the runtime).
  7610 
  7611 * Isar session: The initial use of ROOT.ML is now always timed,
  7612 i.e. the log will show the actual process times, in contrast to the
  7613 elapsed wall-clock time that the outer shell wrapper produces.
  7614 
  7615 * Simplifier: improved handling of bound variables (nameless
  7616 representation, avoid allocating new strings).  Simprocs that invoke
  7617 the Simplifier recursively should use Simplifier.inherit_bounds to
  7618 avoid local name clashes.  Failure to do so produces warnings
  7619 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  7620 for further details.
  7621 
  7622 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  7623 bindings for all theorems stored within a given theory; this may help
  7624 in porting non-Isar theories to Isar ones, while keeping ML proof
  7625 scripts for the time being.
  7626 
  7627 * ML operator HTML.with_charset specifies the charset begin used for
  7628 generated HTML files.  For example:
  7629 
  7630   HTML.with_charset "utf-8" use_thy "Hebrew";
  7631   HTML.with_charset "utf-8" use_thy "Chinese";
  7632 
  7633 
  7634 *** System ***
  7635 
  7636 * Allow symlinks to all proper Isabelle executables (Isabelle,
  7637 isabelle, isatool etc.).
  7638 
  7639 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  7640 isatool doc, isatool mkdir, display_drafts etc.).
  7641 
  7642 * isatool usedir: option -f allows specification of the ML file to be
  7643 used by Isabelle; default is ROOT.ML.
  7644 
  7645 * New isatool version outputs the version identifier of the Isabelle
  7646 distribution being used.
  7647 
  7648 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  7649 (containing Boolean satisfiability problems) into Isabelle/HOL
  7650 theories.
  7651 
  7652 
  7653 
  7654 New in Isabelle2004 (April 2004)
  7655 --------------------------------
  7656 
  7657 *** General ***
  7658 
  7659 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  7660   Replaces linorder.ML.
  7661 
  7662 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  7663   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  7664   (\<a>...\<z>), are now considered normal letters, and can therefore
  7665   be used anywhere where an ASCII letter (a...zA...Z) has until
  7666   now. COMPATIBILITY: This obviously changes the parsing of some
  7667   terms, especially where a symbol has been used as a binder, say
  7668   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  7669   as an identifier.  Fix it by inserting a space around former
  7670   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  7671   existing theory and ML files.
  7672 
  7673 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  7674 
  7675 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  7676   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  7677   a normal (but invisible) letter. For multiple letter subscripts repeat
  7678   \<^isub> like this: x\<^isub>1\<^isub>2.
  7679 
  7680 * Pure: There are now sub-/superscripts that can span more than one
  7681   character. Text between \<^bsub> and \<^esub> is set in subscript in
  7682   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  7683   superscript. The new control characters are not identifier parts.
  7684 
  7685 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  7686   content of "..." to the latex file instead of \isacntrl... . The "..."
  7687   may consist of any printable characters excluding the end bracket >.
  7688 
  7689 * Pure: Using new Isar command "finalconsts" (or the ML functions
  7690   Theory.add_finals or Theory.add_finals_i) it is now possible to
  7691   declare constants "final", which prevents their being given a definition
  7692   later.  It is useful for constants whose behaviour is fixed axiomatically
  7693   rather than definitionally, such as the meta-logic connectives.
  7694 
  7695 * Pure: 'instance' now handles general arities with general sorts
  7696   (i.e. intersections of classes),
  7697 
  7698 * Presentation: generated HTML now uses a CSS style sheet to make layout
  7699   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  7700   It can be changed to alter the colors/layout of generated pages.
  7701 
  7702 
  7703 *** Isar ***
  7704 
  7705 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  7706   cut_tac, subgoal_tac and thin_tac:
  7707   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  7708     locales are no longer forced to write Isar proof scripts.
  7709     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  7710     emulations.
  7711   - INCOMPATIBILITY: names of variables to be instantiated may no
  7712     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  7713     This is consistent with the instantiation attribute "where".
  7714 
  7715 * Attributes "where" and "of":
  7716   - Now take type variables of instantiated theorem into account when reading
  7717     the instantiation string.  This fixes a bug that caused instantiated
  7718     theorems to have too special types in some circumstances.
  7719   - "where" permits explicit instantiations of type variables.
  7720 
  7721 * Calculation commands "moreover" and "also" no longer interfere with
  7722   current facts ("this"), admitting arbitrary combinations with "then"
  7723   and derived forms.
  7724 
  7725 * Locales:
  7726   - Goal statements involving the context element "includes" no longer
  7727     generate theorems with internal delta predicates (those ending on
  7728     "_axioms") in the premise.
  7729     Resolve particular premise with <locale>.intro to obtain old form.
  7730   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  7731     specification and "includes" elements in goal statement.
  7732   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  7733     [intro?] and [elim?] (respectively) by default.
  7734   - Experimental command for instantiation of locales in proof contexts:
  7735         instantiate <label>[<attrs>]: <loc>
  7736     Instantiates locale <loc> and adds all its theorems to the current context
  7737     taking into account their attributes.  Label and attrs are optional
  7738     modifiers, like in theorem declarations.  If present, names of
  7739     instantiated theorems are qualified with <label>, and the attributes
  7740     <attrs> are applied after any attributes these theorems might have already.
  7741       If the locale has assumptions, a chained fact of the form
  7742     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  7743     are derived.  The command does not support old-style locales declared
  7744     with "locale (open)".
  7745       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  7746 
  7747 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  7748   (Isar) contexts.
  7749 
  7750 
  7751 *** HOL ***
  7752 
  7753 * Proof import: new image HOL4 contains the imported library from
  7754   the HOL4 system with about 2500 theorems. It is imported by
  7755   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  7756   can be used like any other Isabelle image.  See
  7757   HOL/Import/HOL/README for more information.
  7758 
  7759 * Simplifier:
  7760   - Much improved handling of linear and partial orders.
  7761     Reasoners for linear and partial orders are set up for type classes
  7762     "linorder" and "order" respectively, and are added to the default simpset
  7763     as solvers.  This means that the simplifier can build transitivity chains
  7764     to solve goals from the assumptions.
  7765   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  7766     of blast or auto after simplification become unnecessary because the goal
  7767     is solved by simplification already.
  7768 
  7769 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  7770     all proved in axiomatic type classes for semirings, rings and fields.
  7771 
  7772 * Numerics:
  7773   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  7774     now formalized using the Ring_and_Field theory mentioned above.
  7775   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  7776     than before, because now they are set up once in a generic manner.
  7777   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  7778     Look for the general versions in Ring_and_Field (and Power if they concern
  7779     exponentiation).
  7780 
  7781 * Type "rat" of the rational numbers is now available in HOL-Complex.
  7782 
  7783 * Records:
  7784   - Record types are now by default printed with their type abbreviation
  7785     instead of the list of all field types. This can be configured via
  7786     the reference "print_record_type_abbr".
  7787   - Simproc "record_upd_simproc" for simplification of multiple updates added
  7788     (not enabled by default).
  7789   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  7790     EX x. x = sel r to True (not enabled by default).
  7791   - Tactic "record_split_simp_tac" to split and simplify records added.
  7792 
  7793 * 'specification' command added, allowing for definition by
  7794   specification.  There is also an 'ax_specification' command that
  7795   introduces the new constants axiomatically.
  7796 
  7797 * arith(_tac) is now able to generate counterexamples for reals as well.
  7798 
  7799 * HOL-Algebra: new locale "ring" for non-commutative rings.
  7800 
  7801 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  7802   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  7803 
  7804 * HOL-Matrix: a first theory for matrices in HOL with an application of
  7805   matrix theory to linear programming.
  7806 
  7807 * Unions and Intersections:
  7808   The latex output syntax of UN and INT has been changed
  7809   from "\Union x \in A. B" to "\Union_{x \in A} B"
  7810   i.e. the index formulae has become a subscript.
  7811   Similarly for "\Union x. B", and for \Inter instead of \Union.
  7812 
  7813 * Unions and Intersections over Intervals:
  7814   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  7815   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  7816   like in normal math, and corresponding versions for < and for intersection.
  7817 
  7818 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  7819   lexicographic dictonary ordering has been added as "lexord".
  7820 
  7821 * ML: the legacy theory structures Int and List have been removed. They had
  7822   conflicted with ML Basis Library structures having the same names.
  7823 
  7824 * 'refute' command added to search for (finite) countermodels.  Only works
  7825   for a fragment of HOL.  The installation of an external SAT solver is
  7826   highly recommended.  See "HOL/Refute.thy" for details.
  7827 
  7828 * 'quickcheck' command: Allows to find counterexamples by evaluating
  7829   formulae under an assignment of free variables to random values.
  7830   In contrast to 'refute', it can deal with inductive datatypes,
  7831   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  7832   for examples.
  7833 
  7834 
  7835 *** HOLCF ***
  7836 
  7837 * Streams now come with concatenation and are part of the HOLCF image
  7838 
  7839 
  7840 
  7841 New in Isabelle2003 (May 2003)
  7842 ------------------------------
  7843 
  7844 *** General ***
  7845 
  7846 * Provers/simplifier:
  7847 
  7848   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  7849     Assumptions are now subject to complete mutual simplification,
  7850     not just from left to right. The simplifier now preserves
  7851     the order of assumptions.
  7852 
  7853     Potential INCOMPATIBILITY:
  7854 
  7855     -- simp sometimes diverges where the old version did
  7856        not, e.g. invoking simp on the goal
  7857 
  7858         [| P (f x); y = x; f x = f y |] ==> Q
  7859 
  7860        now gives rise to the infinite reduction sequence
  7861 
  7862         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  7863 
  7864        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  7865        kind of problem.
  7866 
  7867     -- Tactics combining classical reasoner and simplification (such as auto)
  7868        are also affected by this change, because many of them rely on
  7869        simp. They may sometimes diverge as well or yield a different numbers
  7870        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  7871        in case of problems. Sometimes subsequent calls to the classical
  7872        reasoner will fail because a preceeding call to the simplifier too
  7873        eagerly simplified the goal, e.g. deleted redundant premises.
  7874 
  7875   - The simplifier trace now shows the names of the applied rewrite rules
  7876 
  7877   - You can limit the number of recursive invocations of the simplifier
  7878     during conditional rewriting (where the simplifie tries to solve the
  7879     conditions before applying the rewrite rule):
  7880     ML "simp_depth_limit := n"
  7881     where n is an integer. Thus you can force termination where previously
  7882     the simplifier would diverge.
  7883 
  7884   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  7885 
  7886   - No longer aborts on failed congruence proof.  Instead, the
  7887     congruence is ignored.
  7888 
  7889 * Pure: New generic framework for extracting programs from constructive
  7890   proofs. See HOL/Extraction.thy for an example instantiation, as well
  7891   as HOL/Extraction for some case studies.
  7892 
  7893 * Pure: The main goal of the proof state is no longer shown by default, only
  7894 the subgoals. This behaviour is controlled by a new flag.
  7895    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  7896 (ML: Proof.show_main_goal).
  7897 
  7898 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  7899 rules whose conclusion matches subgoal 1:
  7900       PG menu: Isabelle/Isar -> Show me -> matching rules
  7901 The rules are ordered by how closely they match the subgoal.
  7902 In particular, rules that solve a subgoal outright are displayed first
  7903 (or rather last, the way they are printed).
  7904 (ML: ProofGeneral.print_intros())
  7905 
  7906 * Pure: New flag trace_unify_fail causes unification to print
  7907 diagnostic information (PG: in trace buffer) when it fails. This is
  7908 useful for figuring out why single step proofs like rule, erule or
  7909 assumption failed.
  7910 
  7911 * Pure: Locale specifications now produce predicate definitions
  7912 according to the body of text (covering assumptions modulo local
  7913 definitions); predicate "loc_axioms" covers newly introduced text,
  7914 while "loc" is cumulative wrt. all included locale expressions; the
  7915 latter view is presented only on export into the global theory
  7916 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  7917 on the old view without predicates;
  7918 
  7919 * Pure: predefined locales "var" and "struct" are useful for sharing
  7920 parameters (as in CASL, for example); just specify something like
  7921 ``var x + var y + struct M'' as import;
  7922 
  7923 * Pure: improved thms_containing: proper indexing of facts instead of
  7924 raw theorems; check validity of results wrt. current name space;
  7925 include local facts of proof configuration (also covers active
  7926 locales), cover fixed variables in index; may use "_" in term
  7927 specification; an optional limit for the number of printed facts may
  7928 be given (the default is 40);
  7929 
  7930 * Pure: disallow duplicate fact bindings within new-style theory files
  7931 (batch-mode only);
  7932 
  7933 * Provers: improved induct method: assumptions introduced by case
  7934 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  7935 the goal statement); "foo" still refers to all facts collectively;
  7936 
  7937 * Provers: the function blast.overloaded has been removed: all constants
  7938 are regarded as potentially overloaded, which improves robustness in exchange
  7939 for slight decrease in efficiency;
  7940 
  7941 * Provers/linorder: New generic prover for transitivity reasoning over
  7942 linear orders.  Note: this prover is not efficient!
  7943 
  7944 * Isar: preview of problems to finish 'show' now produce an error
  7945 rather than just a warning (in interactive mode);
  7946 
  7947 
  7948 *** HOL ***
  7949 
  7950 * arith(_tac)
  7951 
  7952  - Produces a counter example if it cannot prove a goal.
  7953    Note that the counter example may be spurious if the goal is not a formula
  7954    of quantifier-free linear arithmetic.
  7955    In ProofGeneral the counter example appears in the trace buffer.
  7956 
  7957  - Knows about div k and mod k where k is a numeral of type nat or int.
  7958 
  7959  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  7960    linear arithmetic fails. This takes account of quantifiers and divisibility.
  7961    Presburger arithmetic can also be called explicitly via presburger(_tac).
  7962 
  7963 * simp's arithmetic capabilities have been enhanced a bit: it now
  7964 takes ~= in premises into account (by performing a case split);
  7965 
  7966 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  7967 are distributed over a sum of terms;
  7968 
  7969 * New tactic "trans_tac" and method "trans" instantiate
  7970 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  7971 "<=", "<" and "=").
  7972 
  7973 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  7974 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  7975 
  7976 * 'typedef' command has new option "open" to suppress the set
  7977 definition;
  7978 
  7979 * functions Min and Max on finite sets have been introduced (theory
  7980 Finite_Set);
  7981 
  7982 * attribute [symmetric] now works for relations as well; it turns
  7983 (x,y) : R^-1 into (y,x) : R, and vice versa;
  7984 
  7985 * induct over a !!-quantified statement (say !!x1..xn):
  7986   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  7987 
  7988 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  7989 %x. None. Warning: empty_def now refers to the previously hidden definition
  7990 of the empty set.
  7991 
  7992 * Algebra: formalization of classical algebra.  Intended as base for
  7993 any algebraic development in Isabelle.  Currently covers group theory
  7994 (up to Sylow's theorem) and ring theory (Universal Property of
  7995 Univariate Polynomials).  Contributions welcome;
  7996 
  7997 * GroupTheory: deleted, since its material has been moved to Algebra;
  7998 
  7999 * Complex: new directory of the complex numbers with numeric constants,
  8000 nonstandard complex numbers, and some complex analysis, standard and
  8001 nonstandard (Jacques Fleuriot);
  8002 
  8003 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  8004 
  8005 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  8006 Fleuriot);
  8007 
  8008 * Real/HahnBanach: updated and adapted to locales;
  8009 
  8010 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  8011 Gray and Kramer);
  8012 
  8013 * UNITY: added the Meier-Sanders theory of progress sets;
  8014 
  8015 * MicroJava: bytecode verifier and lightweight bytecode verifier
  8016 as abstract algorithms, instantiated to the JVM;
  8017 
  8018 * Bali: Java source language formalization. Type system, operational
  8019 semantics, axiomatic semantics. Supported language features:
  8020 classes, interfaces, objects,virtual methods, static methods,
  8021 static/instance fields, arrays, access modifiers, definite
  8022 assignment, exceptions.
  8023 
  8024 
  8025 *** ZF ***
  8026 
  8027 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  8028 universe, etc.);
  8029 
  8030 * Main ZF: virtually all theories converted to new-style format;
  8031 
  8032 
  8033 *** ML ***
  8034 
  8035 * Pure: Tactic.prove provides sane interface for internal proofs;
  8036 omits the infamous "standard" operation, so this is more appropriate
  8037 than prove_goalw_cterm in many situations (e.g. in simprocs);
  8038 
  8039 * Pure: improved error reporting of simprocs;
  8040 
  8041 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  8042 up simprocs;
  8043 
  8044 
  8045 *** Document preparation ***
  8046 
  8047 * uses \par instead of \\ for line breaks in theory text. This may
  8048 shift some page breaks in large documents. To get the old behaviour
  8049 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  8050 
  8051 * minimized dependencies of isabelle.sty and isabellesym.sty on
  8052 other packages
  8053 
  8054 * \<euro> now needs package babel/greek instead of marvosym (which
  8055 broke \Rightarrow)
  8056 
  8057 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  8058 textcomp package)
  8059 
  8060 
  8061 
  8062 New in Isabelle2002 (March 2002)
  8063 --------------------------------
  8064 
  8065 *** Document preparation ***
  8066 
  8067 * greatly simplified document preparation setup, including more
  8068 graceful interpretation of isatool usedir -i/-d/-D options, and more
  8069 instructive isatool mkdir; users should basically be able to get
  8070 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  8071 users may run a separate document processing stage manually like this:
  8072 "isatool usedir -D output HOL Test && isatool document Test/output";
  8073 
  8074 * theory dependency graph may now be incorporated into documents;
  8075 isatool usedir -g true will produce session_graph.eps/.pdf for use
  8076 with \includegraphics of LaTeX;
  8077 
  8078 * proper spacing of consecutive markup elements, especially text
  8079 blocks after section headings;
  8080 
  8081 * support bold style (for single symbols only), input syntax is like
  8082 this: "\<^bold>\<alpha>" or "\<^bold>A";
  8083 
  8084 * \<bullet> is now output as bold \cdot by default, which looks much
  8085 better in printed text;
  8086 
  8087 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  8088 note that these symbols are currently unavailable in Proof General /
  8089 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  8090 
  8091 * isatool latex no longer depends on changed TEXINPUTS, instead
  8092 isatool document copies the Isabelle style files to the target
  8093 location;
  8094 
  8095 
  8096 *** Isar ***
  8097 
  8098 * Pure/Provers: improved proof by cases and induction;
  8099   - 'case' command admits impromptu naming of parameters (such as
  8100     "case (Suc n)");
  8101   - 'induct' method divinates rule instantiation from the inductive
  8102     claim; no longer requires excessive ?P bindings for proper
  8103     instantiation of cases;
  8104   - 'induct' method properly enumerates all possibilities of set/type
  8105     rules; as a consequence facts may be also passed through *type*
  8106     rules without further ado;
  8107   - 'induct' method now derives symbolic cases from the *rulified*
  8108     rule (before it used to rulify cases stemming from the internal
  8109     atomized version); this means that the context of a non-atomic
  8110     statement becomes is included in the hypothesis, avoiding the
  8111     slightly cumbersome show "PROP ?case" form;
  8112   - 'induct' may now use elim-style induction rules without chaining
  8113     facts, using ``missing'' premises from the goal state; this allows
  8114     rules stemming from inductive sets to be applied in unstructured
  8115     scripts, while still benefitting from proper handling of non-atomic
  8116     statements; NB: major inductive premises need to be put first, all
  8117     the rest of the goal is passed through the induction;
  8118   - 'induct' proper support for mutual induction involving non-atomic
  8119     rule statements (uses the new concept of simultaneous goals, see
  8120     below);
  8121   - append all possible rule selections, but only use the first
  8122     success (no backtracking);
  8123   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  8124   - undeclared rule case names default to numbers 1, 2, 3, ...;
  8125   - added 'print_induct_rules' (covered by help item in recent Proof
  8126     General versions);
  8127   - moved induct/cases attributes to Pure, methods to Provers;
  8128   - generic method setup instantiated for FOL and HOL;
  8129 
  8130 * Pure: support multiple simultaneous goal statements, for example
  8131 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  8132 meta-level mechanism, this acts as if several individual goals had
  8133 been stated separately; in particular common proof methods need to be
  8134 repeated in order to cover all claims; note that a single elimination
  8135 step is *not* sufficient to establish the two conjunctions, so this
  8136 fails:
  8137 
  8138   assume "A & B" then have A and B ..   (*".." fails*)
  8139 
  8140 better use "obtain" in situations as above; alternative refer to
  8141 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  8142 
  8143 * Pure: proper integration with ``locales''; unlike the original
  8144 version by Florian Kammller, Isar locales package high-level proof
  8145 contexts rather than raw logical ones (e.g. we admit to include
  8146 attributes everywhere); operations on locales include merge and
  8147 rename; support for implicit arguments (``structures''); simultaneous
  8148 type-inference over imports and text; see also HOL/ex/Locales.thy for
  8149 some examples;
  8150 
  8151 * Pure: the following commands have been ``localized'', supporting a
  8152 target locale specification "(in name)": 'lemma', 'theorem',
  8153 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  8154 stored both within the locale and at the theory level (exported and
  8155 qualified by the locale name);
  8156 
  8157 * Pure: theory goals may now be specified in ``long'' form, with
  8158 ad-hoc contexts consisting of arbitrary locale elements. for example
  8159 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  8160 definitions may be given, too); the result is a meta-level rule with
  8161 the context elements being discharged in the obvious way;
  8162 
  8163 * Pure: new proof command 'using' allows to augment currently used
  8164 facts after a goal statement ('using' is syntactically analogous to
  8165 'apply', but acts on the goal's facts only); this allows chained facts
  8166 to be separated into parts given before and after a claim, as in
  8167 ``from a and b have C using d and e <proof>'';
  8168 
  8169 * Pure: renamed "antecedent" case to "rule_context";
  8170 
  8171 * Pure: new 'judgment' command records explicit information about the
  8172 object-logic embedding (used by several tools internally); no longer
  8173 use hard-wired "Trueprop";
  8174 
  8175 * Pure: added 'corollary' command;
  8176 
  8177 * Pure: fixed 'token_translation' command;
  8178 
  8179 * Pure: removed obsolete 'exported' attribute;
  8180 
  8181 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  8182 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  8183 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  8184 
  8185 * Pure: method 'atomize' presents local goal premises as object-level
  8186 statements (atomic meta-level propositions); setup controlled via
  8187 rewrite rules declarations of 'atomize' attribute; example
  8188 application: 'induct' method with proper rule statements in improper
  8189 proof *scripts*;
  8190 
  8191 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  8192 now consider the syntactic context of assumptions, giving a better
  8193 chance to get type-inference of the arguments right (this is
  8194 especially important for locales);
  8195 
  8196 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  8197 mode;
  8198 
  8199 * Pure/obtain: the formal conclusion "thesis", being marked as
  8200 ``internal'', may no longer be reference directly in the text;
  8201 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  8202 situations;
  8203 
  8204 * Pure: generic 'sym' attribute which declares a rule both as pure
  8205 'elim?' and for the 'symmetric' operation;
  8206 
  8207 * Pure: marginal comments ``--'' may now occur just anywhere in the
  8208 text; the fixed correlation with particular command syntax has been
  8209 discontinued;
  8210 
  8211 * Pure: new method 'rules' is particularly well-suited for proof
  8212 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  8213 but often produces more compact proof terms with less detours;
  8214 
  8215 * Pure/Provers/classical: simplified integration with pure rule
  8216 attributes and methods; the classical "intro?/elim?/dest?"
  8217 declarations coincide with the pure ones; the "rule" method no longer
  8218 includes classically swapped intros; "intro" and "elim" methods no
  8219 longer pick rules from the context; also got rid of ML declarations
  8220 AddXIs/AddXEs/AddXDs; all of this has some potential for
  8221 INCOMPATIBILITY;
  8222 
  8223 * Provers/classical: attribute 'swapped' produces classical inversions
  8224 of introduction rules;
  8225 
  8226 * Provers/simplifier: 'simplified' attribute may refer to explicit
  8227 rules instead of full simplifier context; 'iff' attribute handles
  8228 conditional rules;
  8229 
  8230 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  8231 
  8232 * HOL: 'recdef' now fails on unfinished automated proofs, use
  8233 "(permissive)" option to recover old behavior;
  8234 
  8235 * HOL: 'inductive' no longer features separate (collective) attributes
  8236 for 'intros' (was found too confusing);
  8237 
  8238 * HOL: properly declared induction rules less_induct and
  8239 wf_induct_rule;
  8240 
  8241 
  8242 *** HOL ***
  8243 
  8244 * HOL: moved over to sane numeral syntax; the new policy is as
  8245 follows:
  8246 
  8247   - 0 and 1 are polymorphic constants, which are defined on any
  8248   numeric type (nat, int, real etc.);
  8249 
  8250   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  8251   binary representation internally;
  8252 
  8253   - type nat has special constructor Suc, and generally prefers Suc 0
  8254   over 1::nat and Suc (Suc 0) over 2::nat;
  8255 
  8256 This change may cause significant problems of INCOMPATIBILITY; here
  8257 are some hints on converting existing sources:
  8258 
  8259   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  8260   entities, so expressions involving "-" (unary or binary minus) need
  8261   to be spaced properly;
  8262 
  8263   - existing occurrences of "1" may need to be constraint "1::nat" or
  8264   even replaced by Suc 0; similar for old "2";
  8265 
  8266   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  8267 
  8268   - remove all special provisions on numerals in proofs;
  8269 
  8270 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  8271 representation (depends on bin_arith_simps in the default context);
  8272 
  8273 * HOL: symbolic syntax for x^2 (numeral 2);
  8274 
  8275 * HOL: the class of all HOL types is now called "type" rather than
  8276 "term"; INCOMPATIBILITY, need to adapt references to this type class
  8277 in axclass/classes, instance/arities, and (usually rare) occurrences
  8278 in typings (of consts etc.); internally the class is called
  8279 "HOL.type", ML programs should refer to HOLogic.typeS;
  8280 
  8281 * HOL/record package improvements:
  8282   - new derived operations "fields" to build a partial record section,
  8283     "extend" to promote a fixed record to a record scheme, and
  8284     "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*
  8285     declared as simp by default;
  8286   - shared operations ("more", "fields", etc.) now need to be always
  8287     qualified) --- potential INCOMPATIBILITY;
  8288   - removed "make_scheme" operations (use "make" with "extend") --
  8289     INCOMPATIBILITY;
  8290   - removed "more" class (simply use "term") -- INCOMPATIBILITY;
  8291   - provides cases/induct rules for use with corresponding Isar
  8292     methods (for concrete records, record schemes, concrete more
  8293     parts, and schematic more parts -- in that order);
  8294   - internal definitions directly based on a light-weight abstract
  8295     theory of product types over typedef rather than datatype;
  8296 
  8297 * HOL: generic code generator for generating executable ML code from
  8298 specifications; specific support for HOL constructs such as inductive
  8299 datatypes and sets, as well as recursive functions; can be invoked
  8300 via 'generate_code' theory section;
  8301 
  8302 * HOL: canonical cases/induct rules for n-tuples (n = 3..7);
  8303 
  8304 * HOL: consolidated and renamed several theories.  In particular:
  8305         Ord.thy has been absorbed into HOL.thy
  8306         String.thy has been absorbed into List.thy
  8307 
  8308 * HOL: concrete setsum syntax "\<Sum>i:A. b" == "setsum (%i. b) A"
  8309 (beware of argument permutation!);
  8310 
  8311 * HOL: linorder_less_split superseded by linorder_cases;
  8312 
  8313 * HOL/List: "nodups" renamed to "distinct";
  8314 
  8315 * HOL: added "The" definite description operator; move Hilbert's "Eps"
  8316 to peripheral theory "Hilbert_Choice"; some INCOMPATIBILITIES:
  8317   - Ex_def has changed, now need to use some_eq_ex
  8318 
  8319 * HOL: made split_all_tac safe; EXISTING PROOFS MAY FAIL OR LOOP, so
  8320 in this (rare) case use:
  8321 
  8322   delSWrapper "split_all_tac"
  8323   addSbefore ("unsafe_split_all_tac", unsafe_split_all_tac)
  8324 
  8325 * HOL: added safe wrapper "split_conv_tac" to claset; EXISTING PROOFS
  8326 MAY FAIL;
  8327 
  8328 * HOL: introduced f^n = f o ... o f; warning: due to the limits of
  8329 Isabelle's type classes, ^ on functions and relations has too general
  8330 a domain, namely ('a * 'b) set and 'a => 'b; this means that it may be
  8331 necessary to attach explicit type constraints;
  8332 
  8333 * HOL/Relation: the prefix name of the infix "O" has been changed from
  8334 "comp" to "rel_comp"; INCOMPATIBILITY: a few theorems have been
  8335 renamed accordingly (eg "compI" -> "rel_compI").
  8336 
  8337 * HOL: syntax translations now work properly with numerals and records
  8338 expressions;
  8339 
  8340 * HOL: bounded abstraction now uses syntax "%" / "\<lambda>" instead
  8341 of "lam" -- INCOMPATIBILITY;
  8342 
  8343 * HOL: got rid of some global declarations (potential INCOMPATIBILITY
  8344 for ML tools): const "()" renamed "Product_Type.Unity", type "unit"
  8345 renamed "Product_Type.unit";
  8346 
  8347 * HOL: renamed rtrancl_into_rtrancl2 to converse_rtrancl_into_rtrancl
  8348 
  8349 * HOL: removed obsolete theorem "optionE" (use "option.exhaust", or
  8350 the "cases" method);
  8351 
  8352 * HOL/GroupTheory: group theory examples including Sylow's theorem (by
  8353 Florian Kammller);
  8354 
  8355 * HOL/IMP: updated and converted to new-style theory format; several
  8356 parts turned into readable document, with proper Isar proof texts and
  8357 some explanations (by Gerwin Klein);
  8358 
  8359 * HOL-Real: added Complex_Numbers (by Gertrud Bauer);
  8360 
  8361 * HOL-Hyperreal is now a logic image;
  8362 
  8363 
  8364 *** HOLCF ***
  8365 
  8366 * Isar: consts/constdefs supports mixfix syntax for continuous
  8367 operations;
  8368 
  8369 * Isar: domain package adapted to new-style theory format, e.g. see
  8370 HOLCF/ex/Dnat.thy;
  8371 
  8372 * theory Lift: proper use of rep_datatype lift instead of ML hacks --
  8373 potential INCOMPATIBILITY; now use plain induct_tac instead of former
  8374 lift.induct_tac, always use UU instead of Undef;
  8375 
  8376 * HOLCF/IMP: updated and converted to new-style theory;
  8377 
  8378 
  8379 *** ZF ***
  8380 
  8381 * Isar: proper integration of logic-specific tools and packages,
  8382 including theory commands '(co)inductive', '(co)datatype',
  8383 'rep_datatype', 'inductive_cases', as well as methods 'ind_cases',
  8384 'induct_tac', 'case_tac', and 'typecheck' (with attribute 'TC');
  8385 
  8386 * theory Main no longer includes AC; for the Axiom of Choice, base
  8387 your theory on Main_ZFC;
  8388 
  8389 * the integer library now covers quotients and remainders, with many
  8390 laws relating division to addition, multiplication, etc.;
  8391 
  8392 * ZF/UNITY: Chandy and Misra's UNITY is now available in ZF, giving a
  8393 typeless version of the formalism;
  8394 
  8395 * ZF/AC, Coind, IMP, Resid: updated and converted to new-style theory
  8396 format;
  8397 
  8398 * ZF/Induct: new directory for examples of inductive definitions,
  8399 including theory Multiset for multiset orderings; converted to
  8400 new-style theory format;
  8401 
  8402 * ZF: many new theorems about lists, ordinals, etc.;
  8403 
  8404 
  8405 *** General ***
  8406 
  8407 * Pure/kernel: meta-level proof terms (by Stefan Berghofer); reference
  8408 variable proof controls level of detail: 0 = no proofs (only oracle
  8409 dependencies), 1 = lemma dependencies, 2 = compact proof terms; see
  8410 also ref manual for further ML interfaces;
  8411 
  8412 * Pure/axclass: removed obsolete ML interface
  8413 goal_subclass/goal_arity;
  8414 
  8415 * Pure/syntax: new token syntax "num" for plain numerals (without "#"
  8416 of "xnum"); potential INCOMPATIBILITY, since -0, -1 etc. are now
  8417 separate tokens, so expressions involving minus need to be spaced
  8418 properly;
  8419 
  8420 * Pure/syntax: support non-oriented infixes, using keyword "infix"
  8421 rather than "infixl" or "infixr";
  8422 
  8423 * Pure/syntax: concrete syntax for dummy type variables admits genuine
  8424 sort constraint specifications in type inference; e.g. "x::_::foo"
  8425 ensures that the type of "x" is of sort "foo" (but not necessarily a
  8426 type variable);
  8427 
  8428 * Pure/syntax: print modes "type_brackets" and "no_type_brackets"
  8429 control output of nested => (types); the default behavior is
  8430 "type_brackets";
  8431 
  8432 * Pure/syntax: builtin parse translation for "_constify" turns valued
  8433 tokens into AST constants;
  8434 
  8435 * Pure/syntax: prefer later declarations of translations and print
  8436 translation functions; potential INCOMPATIBILITY: need to reverse
  8437 multiple declarations for same syntax element constant;
  8438 
  8439 * Pure/show_hyps reset by default (in accordance to existing Isar
  8440 practice);
  8441 
  8442 * Provers/classical: renamed addaltern to addafter, addSaltern to
  8443 addSafter;
  8444 
  8445 * Provers/clasimp: ``iff'' declarations now handle conditional rules
  8446 as well;
  8447 
  8448 * system: tested support for MacOS X; should be able to get Isabelle +
  8449 Proof General to work in a plain Terminal after installing Poly/ML
  8450 (e.g. from the Isabelle distribution area) and GNU bash alone
  8451 (e.g. from http://www.apple.com); full X11, XEmacs and X-Symbol
  8452 support requires further installations, e.g. from
  8453 http://fink.sourceforge.net/);
  8454 
  8455 * system: support Poly/ML 4.1.1 (able to manage larger heaps);
  8456 
  8457 * system: reduced base memory usage by Poly/ML (approx. 20 MB instead
  8458 of 40 MB), cf. ML_OPTIONS;
  8459 
  8460 * system: Proof General keywords specification is now part of the
  8461 Isabelle distribution (see etc/isar-keywords.el);
  8462 
  8463 * system: support for persistent Proof General sessions (refrain from
  8464 outdating all loaded theories on startup); user may create writable
  8465 logic images like this: ``isabelle -q HOL Test'';
  8466 
  8467 * system: smart selection of Isabelle process versus Isabelle
  8468 interface, accommodates case-insensitive file systems (e.g. HFS+); may
  8469 run both "isabelle" and "Isabelle" even if file names are badly
  8470 damaged (executable inspects the case of the first letter of its own
  8471 name); added separate "isabelle-process" and "isabelle-interface";
  8472 
  8473 * system: refrain from any attempt at filtering input streams; no
  8474 longer support ``8bit'' encoding of old isabelle font, instead proper
  8475 iso-latin characters may now be used; the related isatools
  8476 "symbolinput" and "nonascii" have disappeared as well;
  8477 
  8478 * system: removed old "xterm" interface (the print modes "xterm" and
  8479 "xterm_color" are still available for direct use in a suitable
  8480 terminal);
  8481 
  8482 
  8483 
  8484 New in Isabelle99-2 (February 2001)
  8485 -----------------------------------
  8486 
  8487 *** Overview of INCOMPATIBILITIES ***
  8488 
  8489 * HOL: please note that theories in the Library and elsewhere often use the
  8490 new-style (Isar) format; to refer to their theorems in an ML script you must
  8491 bind them to ML identifers by e.g.      val thm_name = thm "thm_name";
  8492 
  8493 * HOL: inductive package no longer splits induction rule aggressively,
  8494 but only as far as specified by the introductions given; the old
  8495 format may be recovered via ML function complete_split_rule or attribute
  8496 'split_rule (complete)';
  8497 
  8498 * HOL: induct renamed to lfp_induct, lfp_Tarski to lfp_unfold,
  8499 gfp_Tarski to gfp_unfold;
  8500 
  8501 * HOL: contrapos, contrapos2 renamed to contrapos_nn, contrapos_pp;
  8502 
  8503 * HOL: infix "dvd" now has priority 50 rather than 70 (because it is a
  8504 relation); infix "^^" has been renamed "``"; infix "``" has been
  8505 renamed "`"; "univalent" has been renamed "single_valued";
  8506 
  8507 * HOL/Real: "rinv" and "hrinv" replaced by overloaded "inverse"
  8508 operation;
  8509 
  8510 * HOLCF: infix "`" has been renamed "$"; the symbol syntax is \<cdot>;
  8511 
  8512 * Isar: 'obtain' no longer declares "that" fact as simp/intro;
  8513 
  8514 * Isar/HOL: method 'induct' now handles non-atomic goals; as a
  8515 consequence, it is no longer monotonic wrt. the local goal context
  8516 (which is now passed through the inductive cases);
  8517 
  8518 * Document preparation: renamed standard symbols \<ll> to \<lless> and
  8519 \<gg> to \<ggreater>;
  8520 
  8521 
  8522 *** Document preparation ***
  8523 
  8524 * \isabellestyle{NAME} selects version of Isabelle output (currently
  8525 available: are "it" for near math-mode best-style output, "sl" for
  8526 slanted text style, and "tt" for plain type-writer; if no
  8527 \isabellestyle command is given, output is according to slanted
  8528 type-writer);
  8529 
  8530 * support sub/super scripts (for single symbols only), input syntax is
  8531 like this: "A\<^sup>*" or "A\<^sup>\<star>";
  8532 
  8533 * some more standard symbols; see Appendix A of the system manual for
  8534 the complete list of symbols defined in isabellesym.sty;
  8535 
  8536 * improved isabelle style files; more abstract symbol implementation
  8537 (should now use \isamath{...} and \isatext{...} in custom symbol
  8538 definitions);
  8539 
  8540 * antiquotation @{goals} and @{subgoals} for output of *dynamic* goals
  8541 state; Note that presentation of goal states does not conform to
  8542 actual human-readable proof documents.  Please do not include goal
  8543 states into document output unless you really know what you are doing!
  8544 
  8545 * proper indentation of antiquoted output with proportional LaTeX
  8546 fonts;
  8547 
  8548 * no_document ML operator temporarily disables LaTeX document
  8549 generation;
  8550 
  8551 * isatool unsymbolize tunes sources for plain ASCII communication;
  8552 
  8553 
  8554 *** Isar ***
  8555 
  8556 * Pure: Isar now suffers initial goal statements to contain unbound
  8557 schematic variables (this does not conform to actual readable proof
  8558 documents, due to unpredictable outcome and non-compositional proof
  8559 checking); users who know what they are doing may use schematic goals
  8560 for Prolog-style synthesis of proven results;
  8561 
  8562 * Pure: assumption method (an implicit finishing) now handles actual
  8563 rules as well;
  8564 
  8565 * Pure: improved 'obtain' --- moved to Pure, insert "that" into
  8566 initial goal, declare "that" only as Pure intro (only for single
  8567 steps); the "that" rule assumption may now be involved in implicit
  8568 finishing, thus ".." becomes a feasible for trivial obtains;
  8569 
  8570 * Pure: default proof step now includes 'intro_classes'; thus trivial
  8571 instance proofs may be performed by "..";
  8572 
  8573 * Pure: ?thesis / ?this / "..." now work for pure meta-level
  8574 statements as well;
  8575 
  8576 * Pure: more robust selection of calculational rules;
  8577 
  8578 * Pure: the builtin notion of 'finished' goal now includes the ==-refl
  8579 rule (as well as the assumption rule);
  8580 
  8581 * Pure: 'thm_deps' command visualizes dependencies of theorems and
  8582 lemmas, using the graph browser tool;
  8583 
  8584 * Pure: predict failure of "show" in interactive mode;
  8585 
  8586 * Pure: 'thms_containing' now takes actual terms as arguments;
  8587 
  8588 * HOL: improved method 'induct' --- now handles non-atomic goals
  8589 (potential INCOMPATIBILITY); tuned error handling;
  8590 
  8591 * HOL: cases and induct rules now provide explicit hints about the
  8592 number of facts to be consumed (0 for "type" and 1 for "set" rules);
  8593 any remaining facts are inserted into the goal verbatim;
  8594 
  8595 * HOL: local contexts (aka cases) may now contain term bindings as
  8596 well; the 'cases' and 'induct' methods new provide a ?case binding for
  8597 the result to be shown in each case;
  8598 
  8599 * HOL: added 'recdef_tc' command;
  8600 
  8601 * isatool convert assists in eliminating legacy ML scripts;
  8602 
  8603 
  8604 *** HOL ***
  8605 
  8606 * HOL/Library: a collection of generic theories to be used together
  8607 with main HOL; the theory loader path already includes this directory
  8608 by default; the following existing theories have been moved here:
  8609 HOL/Induct/Multiset, HOL/Induct/Acc (as Accessible_Part), HOL/While
  8610 (as While_Combinator), HOL/Lex/Prefix (as List_Prefix);
  8611 
  8612 * HOL/Unix: "Some aspects of Unix file-system security", a typical
  8613 modelling and verification task performed in Isabelle/HOL +
  8614 Isabelle/Isar + Isabelle document preparation (by Markus Wenzel).
  8615 
  8616 * HOL/Algebra: special summation operator SUM no longer exists, it has
  8617 been replaced by setsum; infix 'assoc' now has priority 50 (like
  8618 'dvd'); axiom 'one_not_zero' has been moved from axclass 'ring' to
  8619 'domain', this makes the theory consistent with mathematical
  8620 literature;
  8621 
  8622 * HOL basics: added overloaded operations "inverse" and "divide"
  8623 (infix "/"), syntax for generic "abs" operation, generic summation
  8624 operator \<Sum>;
  8625 
  8626 * HOL/typedef: simplified package, provide more useful rules (see also
  8627 HOL/subset.thy);
  8628 
  8629 * HOL/datatype: induction rule for arbitrarily branching datatypes is
  8630 now expressed as a proper nested rule (old-style tactic scripts may
  8631 require atomize_strip_tac to cope with non-atomic premises);
  8632 
  8633 * HOL: renamed theory "Prod" to "Product_Type", renamed "split" rule
  8634 to "split_conv" (old name still available for compatibility);
  8635 
  8636 * HOL: improved concrete syntax for strings (e.g. allows translation
  8637 rules with string literals);
  8638 
  8639 * HOL-Real-Hyperreal: this extends HOL-Real with the hyperreals
  8640  and Fleuriot's mechanization of analysis, including the transcendental
  8641  functions for the reals;
  8642 
  8643 * HOL/Real, HOL/Hyperreal: improved arithmetic simplification;
  8644 
  8645 
  8646 *** CTT ***
  8647 
  8648 * CTT: x-symbol support for Pi, Sigma, -->, : (membership); note that
  8649 "lam" is displayed as TWO lambda-symbols
  8650 
  8651 * CTT: theory Main now available, containing everything (that is, Bool
  8652 and Arith);
  8653 
  8654 
  8655 *** General ***
  8656 
  8657 * Pure: the Simplifier has been implemented properly as a derived rule
  8658 outside of the actual kernel (at last!); the overall performance
  8659 penalty in practical applications is about 50%, while reliability of
  8660 the Isabelle inference kernel has been greatly improved;
  8661 
  8662 * print modes "brackets" and "no_brackets" control output of nested =>
  8663 (types) and ==> (props); the default behaviour is "brackets";
  8664 
  8665 * Provers: fast_tac (and friends) now handle actual object-logic rules
  8666 as assumptions as well;
  8667 
  8668 * system: support Poly/ML 4.0;
  8669 
  8670 * system: isatool install handles KDE version 1 or 2;
  8671 
  8672 
  8673 
  8674 New in Isabelle99-1 (October 2000)
  8675 ----------------------------------
  8676 
  8677 *** Overview of INCOMPATIBILITIES ***
  8678 
  8679 * HOL: simplification of natural numbers is much changed; to partly
  8680 recover the old behaviour (e.g. to prevent n+n rewriting to #2*n)
  8681 issue the following ML commands:
  8682 
  8683   Delsimprocs Nat_Numeral_Simprocs.cancel_numerals;
  8684   Delsimprocs [Nat_Numeral_Simprocs.combine_numerals];
  8685 
  8686 * HOL: simplification no longer dives into case-expressions; this is
  8687 controlled by "t.weak_case_cong" for each datatype t;
  8688 
  8689 * HOL: nat_less_induct renamed to less_induct;
  8690 
  8691 * HOL: systematic renaming of the SOME (Eps) rules, may use isatool
  8692 fixsome to patch .thy and .ML sources automatically;
  8693 
  8694   select_equality  -> some_equality
  8695   select_eq_Ex     -> some_eq_ex
  8696   selectI2EX       -> someI2_ex
  8697   selectI2         -> someI2
  8698   selectI          -> someI
  8699   select1_equality -> some1_equality
  8700   Eps_sym_eq       -> some_sym_eq_trivial
  8701   Eps_eq           -> some_eq_trivial
  8702 
  8703 * HOL: exhaust_tac on datatypes superceded by new generic case_tac;
  8704 
  8705 * HOL: removed obsolete theorem binding expand_if (refer to split_if
  8706 instead);
  8707 
  8708 * HOL: the recursion equations generated by 'recdef' are now called
  8709 f.simps instead of f.rules;
  8710 
  8711 * HOL: qed_spec_mp now also handles bounded ALL as well;
  8712 
  8713 * HOL: 0 is now overloaded, so the type constraint ":: nat" may
  8714 sometimes be needed;
  8715 
  8716 * HOL: the constant for "f``x" is now "image" rather than "op ``";
  8717 
  8718 * HOL: the constant for "f-``x" is now "vimage" rather than "op -``";
  8719 
  8720 * HOL: the disjoint sum is now "<+>" instead of "Plus"; the cartesian
  8721 product is now "<*>" instead of "Times"; the lexicographic product is
  8722 now "<*lex*>" instead of "**";
  8723 
  8724 * HOL: theory Sexp is now in HOL/Induct examples (it used to be part
  8725 of main HOL, but was unused); better use HOL's datatype package;
  8726 
  8727 * HOL: removed "symbols" syntax for constant "override" of theory Map;
  8728 the old syntax may be recovered as follows:
  8729 
  8730   syntax (symbols)
  8731     override  :: "('a ~=> 'b) => ('a ~=> 'b) => ('a ~=> 'b)"
  8732       (infixl "\\<oplus>" 100)
  8733 
  8734 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  8735 
  8736 * HOL/ML: even fewer consts are declared as global (see theories Ord,
  8737 Lfp, Gfp, WF); this only affects ML packages that refer to const names
  8738 internally;
  8739 
  8740 * HOL and ZF: syntax for quotienting wrt an equivalence relation
  8741 changed from A/r to A//r;
  8742 
  8743 * ZF: new treatment of arithmetic (nat & int) may break some old
  8744 proofs;
  8745 
  8746 * Isar: renamed some attributes (RS -> THEN, simplify -> simplified,
  8747 rulify -> rule_format, elimify -> elim_format, ...);
  8748 
  8749 * Isar/Provers: intro/elim/dest attributes changed; renamed
  8750 intro/intro!/intro!! flags to intro!/intro/intro? (in most cases, one
  8751 should have to change intro!! to intro? only); replaced "delrule" by
  8752 "rule del";
  8753 
  8754 * Isar/HOL: renamed "intrs" to "intros" in inductive definitions;
  8755 
  8756 * Provers: strengthened force_tac by using new first_best_tac;
  8757 
  8758 * LaTeX document preparation: several changes of isabelle.sty (see
  8759 lib/texinputs);
  8760 
  8761 
  8762 *** Document preparation ***
  8763 
  8764 * formal comments (text blocks etc.) in new-style theories may now
  8765 contain antiquotations of thm/prop/term/typ/text to be presented
  8766 according to latex print mode; concrete syntax is like this:
  8767 @{term[show_types] "f(x) = a + x"};
  8768 
  8769 * isatool mkdir provides easy setup of Isabelle session directories,
  8770 including proper document sources;
  8771 
  8772 * generated LaTeX sources are now deleted after successful run
  8773 (isatool document -c); may retain a copy somewhere else via -D option
  8774 of isatool usedir;
  8775 
  8776 * isatool usedir -D now lets isatool latex -o sty update the Isabelle
  8777 style files, achieving self-contained LaTeX sources and simplifying
  8778 LaTeX debugging;
  8779 
  8780 * old-style theories now produce (crude) LaTeX output as well;
  8781 
  8782 * browser info session directories are now self-contained (may be put
  8783 on WWW server seperately); improved graphs of nested sessions; removed
  8784 graph for 'all sessions';
  8785 
  8786 * several improvements in isabelle style files; \isabellestyle{it}
  8787 produces fake math mode output; \isamarkupheader is now \section by
  8788 default; see lib/texinputs/isabelle.sty etc.;
  8789 
  8790 
  8791 *** Isar ***
  8792 
  8793 * Isar/Pure: local results and corresponding term bindings are now
  8794 subject to Hindley-Milner polymorphism (similar to ML); this
  8795 accommodates incremental type-inference very nicely;
  8796 
  8797 * Isar/Pure: new derived language element 'obtain' supports
  8798 generalized existence reasoning;
  8799 
  8800 * Isar/Pure: new calculational elements 'moreover' and 'ultimately'
  8801 support accumulation of results, without applying any rules yet;
  8802 useful to collect intermediate results without explicit name
  8803 references, and for use with transitivity rules with more than 2
  8804 premises;
  8805 
  8806 * Isar/Pure: scalable support for case-analysis type proofs: new
  8807 'case' language element refers to local contexts symbolically, as
  8808 produced by certain proof methods; internally, case names are attached
  8809 to theorems as "tags";
  8810 
  8811 * Isar/Pure: theory command 'hide' removes declarations from
  8812 class/type/const name spaces;
  8813 
  8814 * Isar/Pure: theory command 'defs' supports option "(overloaded)" to
  8815 indicate potential overloading;
  8816 
  8817 * Isar/Pure: changed syntax of local blocks from {{ }} to { };
  8818 
  8819 * Isar/Pure: syntax of sorts made 'inner', i.e. have to write
  8820 "{a,b,c}" instead of {a,b,c};
  8821 
  8822 * Isar/Pure now provides its own version of intro/elim/dest
  8823 attributes; useful for building new logics, but beware of confusion
  8824 with the version in Provers/classical;
  8825 
  8826 * Isar/Pure: the local context of (non-atomic) goals is provided via
  8827 case name 'antecedent';
  8828 
  8829 * Isar/Pure: removed obsolete 'transfer' attribute (transfer of thms
  8830 to the current context is now done automatically);
  8831 
  8832 * Isar/Pure: theory command 'method_setup' provides a simple interface
  8833 for definining proof methods in ML;
  8834 
  8835 * Isar/Provers: intro/elim/dest attributes changed; renamed
  8836 intro/intro!/intro!! flags to intro!/intro/intro? (INCOMPATIBILITY, in
  8837 most cases, one should have to change intro!! to intro? only);
  8838 replaced "delrule" by "rule del";
  8839 
  8840 * Isar/Provers: new 'hypsubst' method, plain 'subst' method and
  8841 'symmetric' attribute (the latter supercedes [RS sym]);
  8842 
  8843 * Isar/Provers: splitter support (via 'split' attribute and 'simp'
  8844 method modifier); 'simp' method: 'only:' modifier removes loopers as
  8845 well (including splits);
  8846 
  8847 * Isar/Provers: Simplifier and Classical methods now support all kind
  8848 of modifiers used in the past, including 'cong', 'iff', etc.
  8849 
  8850 * Isar/Provers: added 'fastsimp' and 'clarsimp' methods (combination
  8851 of Simplifier and Classical reasoner);
  8852 
  8853 * Isar/HOL: new proof method 'cases' and improved version of 'induct'
  8854 now support named cases; major packages (inductive, datatype, primrec,
  8855 recdef) support case names and properly name parameters;
  8856 
  8857 * Isar/HOL: new transitivity rules for substitution in inequalities --
  8858 monotonicity conditions are extracted to be proven at end of
  8859 calculations;
  8860 
  8861 * Isar/HOL: removed 'case_split' thm binding, should use 'cases' proof
  8862 method anyway;
  8863 
  8864 * Isar/HOL: removed old expand_if = split_if; theorems if_splits =
  8865 split_if split_if_asm; datatype package provides theorems foo.splits =
  8866 foo.split foo.split_asm for each datatype;
  8867 
  8868 * Isar/HOL: tuned inductive package, rename "intrs" to "intros"
  8869 (potential INCOMPATIBILITY), emulation of mk_cases feature for proof
  8870 scripts: new 'inductive_cases' command and 'ind_cases' method; (Note:
  8871 use "(cases (simplified))" method in proper proof texts);
  8872 
  8873 * Isar/HOL: added global 'arith_split' attribute for 'arith' method;
  8874 
  8875 * Isar: names of theorems etc. may be natural numbers as well;
  8876 
  8877 * Isar: 'pr' command: optional arguments for goals_limit and
  8878 ProofContext.prems_limit; no longer prints theory contexts, but only
  8879 proof states;
  8880 
  8881 * Isar: diagnostic commands 'pr', 'thm', 'prop', 'term', 'typ' admit
  8882 additional print modes to be specified; e.g. "pr(latex)" will print
  8883 proof state according to the Isabelle LaTeX style;
  8884 
  8885 * Isar: improved support for emulating tactic scripts, including proof
  8886 methods 'rule_tac' etc., 'cut_tac', 'thin_tac', 'subgoal_tac',
  8887 'rename_tac', 'rotate_tac', 'tactic', and 'case_tac' / 'induct_tac'
  8888 (for HOL datatypes);
  8889 
  8890 * Isar: simplified (more robust) goal selection of proof methods: 1st
  8891 goal, all goals, or explicit goal specifier (tactic emulation); thus
  8892 'proof method scripts' have to be in depth-first order;
  8893 
  8894 * Isar: tuned 'let' syntax: replaced 'as' keyword by 'and';
  8895 
  8896 * Isar: removed 'help' command, which hasn't been too helpful anyway;
  8897 should instead use individual commands for printing items
  8898 (print_commands, print_methods etc.);
  8899 
  8900 * Isar: added 'nothing' --- the empty list of theorems;
  8901 
  8902 
  8903 *** HOL ***
  8904 
  8905 * HOL/MicroJava: formalization of a fragment of Java, together with a
  8906 corresponding virtual machine and a specification of its bytecode
  8907 verifier and a lightweight bytecode verifier, including proofs of
  8908 type-safety; by Gerwin Klein, Tobias Nipkow, David von Oheimb, and
  8909 Cornelia Pusch (see also the homepage of project Bali at
  8910 http://isabelle.in.tum.de/Bali/);
  8911 
  8912 * HOL/Algebra: new theory of rings and univariate polynomials, by
  8913 Clemens Ballarin;
  8914 
  8915 * HOL/NumberTheory: fundamental Theorem of Arithmetic, Chinese
  8916 Remainder Theorem, Fermat/Euler Theorem, Wilson's Theorem, by Thomas M
  8917 Rasmussen;
  8918 
  8919 * HOL/Lattice: fundamental concepts of lattice theory and order
  8920 structures, including duals, properties of bounds versus algebraic
  8921 laws, lattice operations versus set-theoretic ones, the Knaster-Tarski
  8922 Theorem for complete lattices etc.; may also serve as a demonstration
  8923 for abstract algebraic reasoning using axiomatic type classes, and
  8924 mathematics-style proof in Isabelle/Isar; by Markus Wenzel;
  8925 
  8926 * HOL/Prolog: a (bare-bones) implementation of Lambda-Prolog, by David
  8927 von Oheimb;
  8928 
  8929 * HOL/IMPP: extension of IMP with local variables and mutually
  8930 recursive procedures, by David von Oheimb;
  8931 
  8932 * HOL/Lambda: converted into new-style theory and document;
  8933 
  8934 * HOL/ex/Multiquote: example of multiple nested quotations and
  8935 anti-quotations -- basically a generalized version of de-Bruijn
  8936 representation; very useful in avoiding lifting of operations;
  8937 
  8938 * HOL/record: added general record equality rule to simpset; fixed
  8939 select-update simplification procedure to handle extended records as
  8940 well; admit "r" as field name;
  8941 
  8942 * HOL: 0 is now overloaded over the new sort "zero", allowing its use with
  8943 other numeric types and also as the identity of groups, rings, etc.;
  8944 
  8945 * HOL: new axclass plus_ac0 for addition with the AC-laws and 0 as identity.
  8946 Types nat and int belong to this axclass;
  8947 
  8948 * HOL: greatly improved simplification involving numerals of type nat, int, real:
  8949    (i + #8 + j) = Suc k simplifies to  #7 + (i + j) = k
  8950    i*j + k + j*#3*i     simplifies to  #4*(i*j) + k
  8951   two terms #m*u and #n*u are replaced by #(m+n)*u
  8952     (where #m, #n and u can implicitly be 1; this is simproc combine_numerals)
  8953   and the term/formula #m*u+x ~~ #n*u+y simplifies simplifies to #(m-n)+x ~~ y
  8954     or x ~~ #(n-m)+y, where ~~ is one of = < <= or - (simproc cancel_numerals);
  8955 
  8956 * HOL: meson_tac is available (previously in ex/meson.ML); it is a
  8957 powerful prover for predicate logic but knows nothing of clasets; see
  8958 ex/mesontest.ML and ex/mesontest2.ML for example applications;
  8959 
  8960 * HOL: new version of "case_tac" subsumes both boolean case split and
  8961 "exhaust_tac" on datatypes; INCOMPATIBILITY: exhaust_tac no longer
  8962 exists, may define val exhaust_tac = case_tac for ad-hoc portability;
  8963 
  8964 * HOL: simplification no longer dives into case-expressions: only the
  8965 selector expression is simplified, but not the remaining arms; to
  8966 enable full simplification of case-expressions for datatype t, you may
  8967 remove t.weak_case_cong from the simpset, either globally (Delcongs
  8968 [thm"t.weak_case_cong"];) or locally (delcongs [...]).
  8969 
  8970 * HOL/recdef: the recursion equations generated by 'recdef' for
  8971 function 'f' are now called f.simps instead of f.rules; if all
  8972 termination conditions are proved automatically, these simplification
  8973 rules are added to the simpset, as in primrec; rules may be named
  8974 individually as well, resulting in a separate list of theorems for
  8975 each equation;
  8976 
  8977 * HOL/While is a new theory that provides a while-combinator. It
  8978 permits the definition of tail-recursive functions without the
  8979 provision of a termination measure. The latter is necessary once the
  8980 invariant proof rule for while is applied.
  8981 
  8982 * HOL: new (overloaded) notation for the set of elements below/above
  8983 some element: {..u}, {..u(}, {l..}, {)l..}. See theory SetInterval.
  8984 
  8985 * HOL: theorems impI, allI, ballI bound as "strip";
  8986 
  8987 * HOL: new tactic induct_thm_tac: thm -> string -> int -> tactic
  8988 induct_tac th "x1 ... xn" expects th to have a conclusion of the form
  8989 P v1 ... vn and abbreviates res_inst_tac [("v1","x1"),...,("vn","xn")] th;
  8990 
  8991 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  8992 
  8993 * HOL: theory Sexp now in HOL/Induct examples (it used to be part of
  8994 main HOL, but was unused);
  8995 
  8996 * HOL: fewer consts declared as global (e.g. have to refer to
  8997 "Lfp.lfp" instead of "lfp" internally; affects ML packages only);
  8998 
  8999 * HOL: tuned AST representation of nested pairs, avoiding bogus output
  9000 in case of overlap with user translations (e.g. judgements over
  9001 tuples); (note that the underlying logical represenation is still
  9002 bogus);
  9003 
  9004 
  9005 *** ZF ***
  9006 
  9007 * ZF: simplification automatically cancels common terms in arithmetic
  9008 expressions over nat and int;
  9009 
  9010 * ZF: new treatment of nat to minimize type-checking: all operators
  9011 coerce their operands to a natural number using the function natify,
  9012 making the algebraic laws unconditional;
  9013 
  9014 * ZF: as above, for int: operators coerce their operands to an integer
  9015 using the function intify;
  9016 
  9017 * ZF: the integer library now contains many of the usual laws for the
  9018 orderings, including $<=, and monotonicity laws for $+ and $*;
  9019 
  9020 * ZF: new example ZF/ex/NatSum to demonstrate integer arithmetic
  9021 simplification;
  9022 
  9023 * FOL and ZF: AddIffs now available, giving theorems of the form P<->Q
  9024 to the simplifier and classical reasoner simultaneously;
  9025 
  9026 
  9027 *** General ***
  9028 
  9029 * Provers: blast_tac now handles actual object-logic rules as
  9030 assumptions; note that auto_tac uses blast_tac internally as well;
  9031 
  9032 * Provers: new functions rulify/rulify_no_asm: thm -> thm for turning
  9033 outer -->/All/Ball into ==>/!!; qed_spec_mp now uses rulify_no_asm;
  9034 
  9035 * Provers: delrules now handles destruct rules as well (no longer need
  9036 explicit make_elim);
  9037 
  9038 * Provers: Blast_tac now warns of and ignores "weak elimination rules" e.g.
  9039   [| inj ?f;          ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
  9040 use instead the strong form,
  9041   [| inj ?f; ~ ?W ==> ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
  9042 in HOL, FOL and ZF the function cla_make_elim will create such rules
  9043 from destruct-rules;
  9044 
  9045 * Provers: Simplifier.easy_setup provides a fast path to basic
  9046 Simplifier setup for new object-logics;
  9047 
  9048 * Pure: AST translation rules no longer require constant head on LHS;
  9049 
  9050 * Pure: improved name spaces: ambiguous output is qualified; support
  9051 for hiding of names;
  9052 
  9053 * system: smart setup of canonical ML_HOME, ISABELLE_INTERFACE, and
  9054 XSYMBOL_HOME; no longer need to do manual configuration in most
  9055 situations;
  9056 
  9057 * system: compression of ML heaps images may now be controlled via -c
  9058 option of isabelle and isatool usedir (currently only observed by
  9059 Poly/ML);
  9060 
  9061 * system: isatool installfonts may handle X-Symbol fonts as well (very
  9062 useful for remote X11);
  9063 
  9064 * system: provide TAGS file for Isabelle sources;
  9065 
  9066 * ML: infix 'OF' is a version of 'MRS' with more appropriate argument
  9067 order;
  9068 
  9069 * ML: renamed flags Syntax.trace_norm_ast to Syntax.trace_ast; global
  9070 timing flag supersedes proof_timing and Toplevel.trace;
  9071 
  9072 * ML: new combinators |>> and |>>> for incremental transformations
  9073 with secondary results (e.g. certain theory extensions):
  9074 
  9075 * ML: PureThy.add_defs gets additional argument to indicate potential
  9076 overloading (usually false);
  9077 
  9078 * ML: PureThy.add_thms/add_axioms/add_defs now return theorems as
  9079 results;
  9080 
  9081 
  9082 
  9083 New in Isabelle99 (October 1999)
  9084 --------------------------------
  9085 
  9086 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  9087 
  9088 * HOL: The THEN and ELSE parts of conditional expressions (if P then x else y)
  9089 are no longer simplified.  (This allows the simplifier to unfold recursive
  9090 functional programs.)  To restore the old behaviour, declare
  9091 
  9092     Delcongs [if_weak_cong];
  9093 
  9094 * HOL: Removed the obsolete syntax "Compl A"; use -A for set
  9095 complement;
  9096 
  9097 * HOL: the predicate "inj" is now defined by translation to "inj_on";
  9098 
  9099 * HOL/datatype: mutual_induct_tac no longer exists --
  9100   use induct_tac "x_1 ... x_n" instead of mutual_induct_tac ["x_1", ..., "x_n"]
  9101 
  9102 * HOL/typedef: fixed type inference for representing set; type
  9103 arguments now have to occur explicitly on the rhs as type constraints;
  9104 
  9105 * ZF: The con_defs part of an inductive definition may no longer refer
  9106 to constants declared in the same theory;
  9107 
  9108 * HOL, ZF: the function mk_cases, generated by the inductive
  9109 definition package, has lost an argument.  To simplify its result, it
  9110 uses the default simpset instead of a supplied list of theorems.
  9111 
  9112 * HOL/List: the constructors of type list are now Nil and Cons;
  9113 
  9114 * Simplifier: the type of the infix ML functions
  9115         setSSolver addSSolver setSolver addSolver
  9116 is now  simpset * solver -> simpset  where `solver' is a new abstract type
  9117 for packaging solvers. A solver is created via
  9118         mk_solver: string -> (thm list -> int -> tactic) -> solver
  9119 where the string argument is only a comment.
  9120 
  9121 
  9122 *** Proof tools ***
  9123 
  9124 * Provers/Arith/fast_lin_arith.ML contains a functor for creating a
  9125 decision procedure for linear arithmetic. Currently it is used for
  9126 types `nat', `int', and `real' in HOL (see below); it can, should and
  9127 will be instantiated for other types and logics as well.
  9128 
  9129 * The simplifier now accepts rewrite rules with flexible heads, eg
  9130      hom ?f ==> ?f(?x+?y) = ?f ?x + ?f ?y
  9131   They are applied like any rule with a non-pattern lhs, i.e. by first-order
  9132   matching.
  9133 
  9134 
  9135 *** General ***
  9136 
  9137 * New Isabelle/Isar subsystem provides an alternative to traditional
  9138 tactical theorem proving; together with the ProofGeneral/isar user
  9139 interface it offers an interactive environment for developing human
  9140 readable proof documents (Isar == Intelligible semi-automated
  9141 reasoning); for further information see isatool doc isar-ref,
  9142 src/HOL/Isar_examples and http://isabelle.in.tum.de/Isar/
  9143 
  9144 * improved and simplified presentation of theories: better HTML markup
  9145 (including colors), graph views in several sizes; isatool usedir now
  9146 provides a proper interface for user theories (via -P option); actual
  9147 document preparation based on (PDF)LaTeX is available as well (for
  9148 new-style theories only); see isatool doc system for more information;
  9149 
  9150 * native support for Proof General, both for classic Isabelle and
  9151 Isabelle/Isar;
  9152 
  9153 * ML function thm_deps visualizes dependencies of theorems and lemmas,
  9154 using the graph browser tool;
  9155 
  9156 * Isabelle manuals now also available as PDF;
  9157 
  9158 * theory loader rewritten from scratch (may not be fully
  9159 bug-compatible); old loadpath variable has been replaced by show_path,
  9160 add_path, del_path, reset_path functions; new operations such as
  9161 update_thy, touch_thy, remove_thy, use/update_thy_only (see also
  9162 isatool doc ref);
  9163 
  9164 * improved isatool install: option -k creates KDE application icon,
  9165 option -p DIR installs standalone binaries;
  9166 
  9167 * added ML_PLATFORM setting (useful for cross-platform installations);
  9168 more robust handling of platform specific ML images for SML/NJ;
  9169 
  9170 * the settings environment is now statically scoped, i.e. it is never
  9171 created again in sub-processes invoked from isabelle, isatool, or
  9172 Isabelle;
  9173 
  9174 * path element specification '~~' refers to '$ISABELLE_HOME';
  9175 
  9176 * in locales, the "assumes" and "defines" parts may be omitted if
  9177 empty;
  9178 
  9179 * new print_mode "xsymbols" for extended symbol support (e.g. genuine
  9180 long arrows);
  9181 
  9182 * new print_mode "HTML";
  9183 
  9184 * new flag show_tags controls display of tags of theorems (which are
  9185 basically just comments that may be attached by some tools);
  9186 
  9187 * Isamode 2.6 requires patch to accomodate change of Isabelle font
  9188 mode and goal output format:
  9189 
  9190 diff -r Isamode-2.6/elisp/isa-load.el Isamode/elisp/isa-load.el
  9191 244c244
  9192 <       (list (isa-getenv "ISABELLE") "-msymbols" logic-name)
  9193 ---
  9194 >       (list (isa-getenv "ISABELLE") "-misabelle_font" "-msymbols" logic-name)
  9195 diff -r Isabelle-2.6/elisp/isa-proofstate.el Isamode/elisp/isa-proofstate.el
  9196 181c181
  9197 < (defconst proofstate-proofstart-regexp "^Level [0-9]+$"
  9198 ---
  9199 > (defconst proofstate-proofstart-regexp "^Level [0-9]+"
  9200 
  9201 * function bind_thms stores lists of theorems (cf. bind_thm);
  9202 
  9203 * new shorthand tactics ftac, eatac, datac, fatac;
  9204 
  9205 * qed (and friends) now accept "" as result name; in that case the
  9206 theorem is not stored, but proper checks and presentation of the
  9207 result still apply;
  9208 
  9209 * theorem database now also indexes constants "Trueprop", "all",
  9210 "==>", "=="; thus thms_containing, findI etc. may retrieve more rules;
  9211 
  9212 
  9213 *** HOL ***
  9214 
  9215 ** HOL arithmetic **
  9216 
  9217 * There are now decision procedures for linear arithmetic over nat and
  9218 int:
  9219 
  9220 1. arith_tac copes with arbitrary formulae involving `=', `<', `<=',
  9221 `+', `-', `Suc', `min', `max' and numerical constants; other subterms
  9222 are treated as atomic; subformulae not involving type `nat' or `int'
  9223 are ignored; quantified subformulae are ignored unless they are
  9224 positive universal or negative existential. The tactic has to be
  9225 invoked by hand and can be a little bit slow. In particular, the
  9226 running time is exponential in the number of occurrences of `min' and
  9227 `max', and `-' on `nat'.
  9228 
  9229 2. fast_arith_tac is a cut-down version of arith_tac: it only takes
  9230 (negated) (in)equalities among the premises and the conclusion into
  9231 account (i.e. no compound formulae) and does not know about `min' and
  9232 `max', and `-' on `nat'. It is fast and is used automatically by the
  9233 simplifier.
  9234 
  9235 NB: At the moment, these decision procedures do not cope with mixed
  9236 nat/int formulae where the two parts interact, such as `m < n ==>
  9237 int(m) < int(n)'.
  9238 
  9239 * HOL/Numeral provides a generic theory of numerals (encoded
  9240 efficiently as bit strings); setup for types nat/int/real is in place;
  9241 INCOMPATIBILITY: since numeral syntax is now polymorphic, rather than
  9242 int, existing theories and proof scripts may require a few additional
  9243 type constraints;
  9244 
  9245 * integer division and remainder can now be performed on constant
  9246 arguments;
  9247 
  9248 * many properties of integer multiplication, division and remainder
  9249 are now available;
  9250 
  9251 * An interface to the Stanford Validity Checker (SVC) is available through the
  9252 tactic svc_tac.  Propositional tautologies and theorems of linear arithmetic
  9253 are proved automatically.  SVC must be installed separately, and its results
  9254 must be TAKEN ON TRUST (Isabelle does not check the proofs, but tags any
  9255 invocation of the underlying oracle).  For SVC see
  9256   http://verify.stanford.edu/SVC
  9257 
  9258 * IsaMakefile: the HOL-Real target now builds an actual image;
  9259 
  9260 
  9261 ** HOL misc **
  9262 
  9263 * HOL/Real/HahnBanach: the Hahn-Banach theorem for real vector spaces
  9264 (in Isabelle/Isar) -- by Gertrud Bauer;
  9265 
  9266 * HOL/BCV: generic model of bytecode verification, i.e. data-flow
  9267 analysis for assembly languages with subtypes;
  9268 
  9269 * HOL/TLA (Lamport's Temporal Logic of Actions): major reorganization
  9270 -- avoids syntactic ambiguities and treats state, transition, and
  9271 temporal levels more uniformly; introduces INCOMPATIBILITIES due to
  9272 changed syntax and (many) tactics;
  9273 
  9274 * HOL/inductive: Now also handles more general introduction rules such
  9275   as "ALL y. (y, x) : r --> y : acc r ==> x : acc r"; monotonicity
  9276   theorems are now maintained within the theory (maintained via the
  9277   "mono" attribute);
  9278 
  9279 * HOL/datatype: Now also handles arbitrarily branching datatypes
  9280   (using function types) such as
  9281 
  9282   datatype 'a tree = Atom 'a | Branch "nat => 'a tree"
  9283 
  9284 * HOL/record: record_simproc (part of the default simpset) takes care
  9285 of selectors applied to updated records; record_split_tac is no longer
  9286 part of the default claset; update_defs may now be removed from the
  9287 simpset in many cases; COMPATIBILITY: old behavior achieved by
  9288 
  9289   claset_ref () := claset() addSWrapper record_split_wrapper;
  9290   Delsimprocs [record_simproc]
  9291 
  9292 * HOL/typedef: fixed type inference for representing set; type
  9293 arguments now have to occur explicitly on the rhs as type constraints;
  9294 
  9295 * HOL/recdef (TFL): 'congs' syntax now expects comma separated list of theorem
  9296 names rather than an ML expression;
  9297 
  9298 * HOL/defer_recdef (TFL): like recdef but the well-founded relation can be
  9299 supplied later.  Program schemes can be defined, such as
  9300     "While B C s = (if B s then While B C (C s) else s)"
  9301 where the well-founded relation can be chosen after B and C have been given.
  9302 
  9303 * HOL/List: the constructors of type list are now Nil and Cons;
  9304 INCOMPATIBILITY: while [] and infix # syntax is still there, of
  9305 course, ML tools referring to List.list.op # etc. have to be adapted;
  9306 
  9307 * HOL_quantifiers flag superseded by "HOL" print mode, which is
  9308 disabled by default; run isabelle with option -m HOL to get back to
  9309 the original Gordon/HOL-style output;
  9310 
  9311 * HOL/Ord.thy: new bounded quantifier syntax (input only): ALL x<y. P,
  9312 ALL x<=y. P, EX x<y. P, EX x<=y. P;
  9313 
  9314 * HOL basic syntax simplified (more orthogonal): all variants of
  9315 All/Ex now support plain / symbolic / HOL notation; plain syntax for
  9316 Eps operator is provided as well: "SOME x. P[x]";
  9317 
  9318 * HOL/Sum.thy: sum_case has been moved to HOL/Datatype;
  9319 
  9320 * HOL/Univ.thy: infix syntax <*>, <+>, <**>, <+> eliminated and made
  9321 thus available for user theories;
  9322 
  9323 * HOLCF/IOA/Sequents: renamed 'Cons' to 'Consq' to avoid clash with
  9324 HOL/List; hardly an INCOMPATIBILITY since '>>' syntax is used all the
  9325 time;
  9326 
  9327 * HOL: new tactic smp_tac: int -> int -> tactic, which applies spec
  9328 several times and then mp;
  9329 
  9330 
  9331 *** LK ***
  9332 
  9333 * the notation <<...>> is now available as a notation for sequences of
  9334 formulas;
  9335 
  9336 * the simplifier is now installed
  9337 
  9338 * the axiom system has been generalized (thanks to Soren Heilmann)
  9339 
  9340 * the classical reasoner now has a default rule database
  9341 
  9342 
  9343 *** ZF ***
  9344 
  9345 * new primrec section allows primitive recursive functions to be given
  9346 directly (as in HOL) over datatypes and the natural numbers;
  9347 
  9348 * new tactics induct_tac and exhaust_tac for induction (or case
  9349 analysis) over datatypes and the natural numbers;
  9350 
  9351 * the datatype declaration of type T now defines the recursor T_rec;
  9352 
  9353 * simplification automatically does freeness reasoning for datatype
  9354 constructors;
  9355 
  9356 * automatic type-inference, with AddTCs command to insert new
  9357 type-checking rules;
  9358 
  9359 * datatype introduction rules are now added as Safe Introduction rules
  9360 to the claset;
  9361 
  9362 * the syntax "if P then x else y" is now available in addition to
  9363 if(P,x,y);
  9364 
  9365 
  9366 *** Internal programming interfaces ***
  9367 
  9368 * tuned simplifier trace output; new flag debug_simp;
  9369 
  9370 * structures Vartab / Termtab (instances of TableFun) offer efficient
  9371 tables indexed by indexname_ord / term_ord (compatible with aconv);
  9372 
  9373 * AxClass.axclass_tac lost the theory argument;
  9374 
  9375 * tuned current_goals_markers semantics: begin / end goal avoids
  9376 printing empty lines;
  9377 
  9378 * removed prs and prs_fn hook, which was broken because it did not
  9379 include \n in its semantics, forcing writeln to add one
  9380 uncoditionally; replaced prs_fn by writeln_fn; consider std_output:
  9381 string -> unit if you really want to output text without newline;
  9382 
  9383 * Symbol.output subject to print mode; INCOMPATIBILITY: defaults to
  9384 plain output, interface builders may have to enable 'isabelle_font'
  9385 mode to get Isabelle font glyphs as before;
  9386 
  9387 * refined token_translation interface; INCOMPATIBILITY: output length
  9388 now of type real instead of int;
  9389 
  9390 * theory loader actions may be traced via new ThyInfo.add_hook
  9391 interface (see src/Pure/Thy/thy_info.ML); example application: keep
  9392 your own database of information attached to *whole* theories -- as
  9393 opposed to intra-theory data slots offered via TheoryDataFun;
  9394 
  9395 * proper handling of dangling sort hypotheses (at last!);
  9396 Thm.strip_shyps and Drule.strip_shyps_warning take care of removing
  9397 extra sort hypotheses that can be witnessed from the type signature;
  9398 the force_strip_shyps flag is gone, any remaining shyps are simply
  9399 left in the theorem (with a warning issued by strip_shyps_warning);
  9400 
  9401 
  9402 
  9403 New in Isabelle98-1 (October 1998)
  9404 ----------------------------------
  9405 
  9406 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  9407 
  9408 * several changes of automated proof tools;
  9409 
  9410 * HOL: major changes to the inductive and datatype packages, including
  9411 some minor incompatibilities of theory syntax;
  9412 
  9413 * HOL: renamed r^-1 to 'converse' from 'inverse'; 'inj_onto' is now
  9414 called `inj_on';
  9415 
  9416 * HOL: removed duplicate thms in Arith:
  9417   less_imp_add_less  should be replaced by  trans_less_add1
  9418   le_imp_add_le      should be replaced by  trans_le_add1
  9419 
  9420 * HOL: unary minus is now overloaded (new type constraints may be
  9421 required);
  9422 
  9423 * HOL and ZF: unary minus for integers is now #- instead of #~.  In
  9424 ZF, expressions such as n#-1 must be changed to n#- 1, since #-1 is
  9425 now taken as an integer constant.
  9426 
  9427 * Pure: ML function 'theory_of' renamed to 'theory';
  9428 
  9429 
  9430 *** Proof tools ***
  9431 
  9432 * Simplifier:
  9433   1. Asm_full_simp_tac is now more aggressive.
  9434      1. It will sometimes reorient premises if that increases their power to
  9435         simplify.
  9436      2. It does no longer proceed strictly from left to right but may also
  9437         rotate premises to achieve further simplification.
  9438      For compatibility reasons there is now Asm_lr_simp_tac which is like the
  9439      old Asm_full_simp_tac in that it does not rotate premises.
  9440   2. The simplifier now knows a little bit about nat-arithmetic.
  9441 
  9442 * Classical reasoner: wrapper mechanism for the classical reasoner now
  9443 allows for selected deletion of wrappers, by introduction of names for
  9444 wrapper functionals.  This implies that addbefore, addSbefore,
  9445 addaltern, and addSaltern now take a pair (name, tactic) as argument,
  9446 and that adding two tactics with the same name overwrites the first
  9447 one (emitting a warning).
  9448   type wrapper = (int -> tactic) -> (int -> tactic)
  9449   setWrapper, setSWrapper, compWrapper and compSWrapper are replaced by
  9450   addWrapper, addSWrapper: claset * (string * wrapper) -> claset
  9451   delWrapper, delSWrapper: claset *  string            -> claset
  9452   getWrapper is renamed to appWrappers, getSWrapper to appSWrappers;
  9453 
  9454 * Classical reasoner: addbefore/addSbefore now have APPEND/ORELSE
  9455 semantics; addbefore now affects only the unsafe part of step_tac
  9456 etc.; this affects addss/auto_tac/force_tac, so EXISTING PROOFS MAY
  9457 FAIL, but proofs should be fixable easily, e.g. by replacing Auto_tac
  9458 by Force_tac;
  9459 
  9460 * Classical reasoner: setwrapper to setWrapper and compwrapper to
  9461 compWrapper; added safe wrapper (and access functions for it);
  9462 
  9463 * HOL/split_all_tac is now much faster and fails if there is nothing
  9464 to split.  Some EXISTING PROOFS MAY REQUIRE ADAPTION because the order
  9465 and the names of the automatically generated variables have changed.
  9466 split_all_tac has moved within claset() from unsafe wrappers to safe
  9467 wrappers, which means that !!-bound variables are split much more
  9468 aggressively, and safe_tac and clarify_tac now split such variables.
  9469 If this splitting is not appropriate, use delSWrapper "split_all_tac".
  9470 Note: the same holds for record_split_tac, which does the job of
  9471 split_all_tac for record fields.
  9472 
  9473 * HOL/Simplifier: Rewrite rules for case distinctions can now be added
  9474 permanently to the default simpset using Addsplits just like
  9475 Addsimps. They can be removed via Delsplits just like
  9476 Delsimps. Lower-case versions are also available.
  9477 
  9478 * HOL/Simplifier: The rule split_if is now part of the default
  9479 simpset. This means that the simplifier will eliminate all occurrences
  9480 of if-then-else in the conclusion of a goal. To prevent this, you can
  9481 either remove split_if completely from the default simpset by
  9482 `Delsplits [split_if]' or remove it in a specific call of the
  9483 simplifier using `... delsplits [split_if]'.  You can also add/delete
  9484 other case splitting rules to/from the default simpset: every datatype
  9485 generates suitable rules `split_t_case' and `split_t_case_asm' (where
  9486 t is the name of the datatype).
  9487 
  9488 * Classical reasoner / Simplifier combination: new force_tac (and
  9489 derivatives Force_tac, force) combines rewriting and classical
  9490 reasoning (and whatever other tools) similarly to auto_tac, but is
  9491 aimed to solve the given subgoal completely.
  9492 
  9493 
  9494 *** General ***
  9495 
  9496 * new top-level commands `Goal' and `Goalw' that improve upon `goal'
  9497 and `goalw': the theory is no longer needed as an explicit argument -
  9498 the current theory context is used; assumptions are no longer returned
  9499 at the ML-level unless one of them starts with ==> or !!; it is
  9500 recommended to convert to these new commands using isatool fixgoal
  9501 (backup your sources first!);
  9502 
  9503 * new top-level commands 'thm' and 'thms' for retrieving theorems from
  9504 the current theory context, and 'theory' to lookup stored theories;
  9505 
  9506 * new theory section 'locale' for declaring constants, assumptions and
  9507 definitions that have local scope;
  9508 
  9509 * new theory section 'nonterminals' for purely syntactic types;
  9510 
  9511 * new theory section 'setup' for generic ML setup functions
  9512 (e.g. package initialization);
  9513 
  9514 * the distribution now includes Isabelle icons: see
  9515 lib/logo/isabelle-{small,tiny}.xpm;
  9516 
  9517 * isatool install - install binaries with absolute references to
  9518 ISABELLE_HOME/bin;
  9519 
  9520 * isatool logo -- create instances of the Isabelle logo (as EPS);
  9521 
  9522 * print mode 'emacs' reserved for Isamode;
  9523 
  9524 * support multiple print (ast) translations per constant name;
  9525 
  9526 * theorems involving oracles are now printed with a suffixed [!];
  9527 
  9528 
  9529 *** HOL ***
  9530 
  9531 * there is now a tutorial on Isabelle/HOL (do 'isatool doc tutorial');
  9532 
  9533 * HOL/inductive package reorganized and improved: now supports mutual
  9534 definitions such as
  9535 
  9536   inductive EVEN ODD
  9537     intrs
  9538       null "0 : EVEN"
  9539       oddI "n : EVEN ==> Suc n : ODD"
  9540       evenI "n : ODD ==> Suc n : EVEN"
  9541 
  9542 new theorem list "elims" contains an elimination rule for each of the
  9543 recursive sets; inductive definitions now handle disjunctive premises
  9544 correctly (also ZF);
  9545 
  9546 INCOMPATIBILITIES: requires Inductive as an ancestor; component
  9547 "mutual_induct" no longer exists - the induction rule is always
  9548 contained in "induct";
  9549 
  9550 
  9551 * HOL/datatype package re-implemented and greatly improved: now
  9552 supports mutually recursive datatypes such as
  9553 
  9554   datatype
  9555     'a aexp = IF_THEN_ELSE ('a bexp) ('a aexp) ('a aexp)
  9556             | SUM ('a aexp) ('a aexp)
  9557             | DIFF ('a aexp) ('a aexp)
  9558             | NUM 'a
  9559   and
  9560     'a bexp = LESS ('a aexp) ('a aexp)
  9561             | AND ('a bexp) ('a bexp)
  9562             | OR ('a bexp) ('a bexp)
  9563 
  9564 as well as indirectly recursive datatypes such as
  9565 
  9566   datatype
  9567     ('a, 'b) term = Var 'a
  9568                   | App 'b ((('a, 'b) term) list)
  9569 
  9570 The new tactic  mutual_induct_tac [<var_1>, ..., <var_n>] i  performs
  9571 induction on mutually / indirectly recursive datatypes.
  9572 
  9573 Primrec equations are now stored in theory and can be accessed via
  9574 <function_name>.simps.
  9575 
  9576 INCOMPATIBILITIES:
  9577 
  9578   - Theories using datatypes must now have theory Datatype as an
  9579     ancestor.
  9580   - The specific <typename>.induct_tac no longer exists - use the
  9581     generic induct_tac instead.
  9582   - natE has been renamed to nat.exhaust - use exhaust_tac
  9583     instead of res_inst_tac ... natE. Note that the variable
  9584     names in nat.exhaust differ from the names in natE, this
  9585     may cause some "fragile" proofs to fail.
  9586   - The theorems split_<typename>_case and split_<typename>_case_asm
  9587     have been renamed to <typename>.split and <typename>.split_asm.
  9588   - Since default sorts of type variables are now handled correctly,
  9589     some datatype definitions may have to be annotated with explicit
  9590     sort constraints.
  9591   - Primrec definitions no longer require function name and type
  9592     of recursive argument.
  9593 
  9594 Consider using isatool fixdatatype to adapt your theories and proof
  9595 scripts to the new package (backup your sources first!).
  9596 
  9597 
  9598 * HOL/record package: considerably improved implementation; now
  9599 includes concrete syntax for record types, terms, updates; theorems
  9600 for surjective pairing and splitting !!-bound record variables; proof
  9601 support is as follows:
  9602 
  9603   1) standard conversions (selectors or updates applied to record
  9604 constructor terms) are part of the standard simpset;
  9605 
  9606   2) inject equations of the form ((x, y) = (x', y')) == x=x' & y=y' are
  9607 made part of standard simpset and claset via addIffs;
  9608 
  9609   3) a tactic for record field splitting (record_split_tac) is part of
  9610 the standard claset (addSWrapper);
  9611 
  9612 To get a better idea about these rules you may retrieve them via
  9613 something like 'thms "foo.simps"' or 'thms "foo.iffs"', where "foo" is
  9614 the name of your record type.
  9615 
  9616 The split tactic 3) conceptually simplifies by the following rule:
  9617 
  9618   "(!!x. PROP ?P x) == (!!a b. PROP ?P (a, b))"
  9619 
  9620 Thus any record variable that is bound by meta-all will automatically
  9621 blow up into some record constructor term, consequently the
  9622 simplifications of 1), 2) apply.  Thus force_tac, auto_tac etc. shall
  9623 solve record problems automatically.
  9624 
  9625 
  9626 * reorganized the main HOL image: HOL/Integ and String loaded by
  9627 default; theory Main includes everything;
  9628 
  9629 * automatic simplification of integer sums and comparisons, using cancellation;
  9630 
  9631 * added option_map_eq_Some and not_Some_eq to the default simpset and claset;
  9632 
  9633 * added disj_not1 = "(~P | Q) = (P --> Q)" to the default simpset;
  9634 
  9635 * many new identities for unions, intersections, set difference, etc.;
  9636 
  9637 * expand_if, expand_split, expand_sum_case and expand_nat_case are now
  9638 called split_if, split_split, split_sum_case and split_nat_case (to go
  9639 with add/delsplits);
  9640 
  9641 * HOL/Prod introduces simplification procedure unit_eq_proc rewriting
  9642 (?x::unit) = (); this is made part of the default simpset, which COULD
  9643 MAKE EXISTING PROOFS FAIL under rare circumstances (consider
  9644 'Delsimprocs [unit_eq_proc];' as last resort); also note that
  9645 unit_abs_eta_conv is added in order to counter the effect of
  9646 unit_eq_proc on (%u::unit. f u), replacing it by f rather than by
  9647 %u.f();
  9648 
  9649 * HOL/Fun INCOMPATIBILITY: `inj_onto' is now called `inj_on' (which
  9650 makes more sense);
  9651 
  9652 * HOL/Set INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
  9653   It and 'sym RS equals0D' are now in the default  claset, giving automatic
  9654   disjointness reasoning but breaking a few old proofs.
  9655 
  9656 * HOL/Relation INCOMPATIBILITY: renamed the relational operator r^-1
  9657 to 'converse' from 'inverse' (for compatibility with ZF and some
  9658 literature);
  9659 
  9660 * HOL/recdef can now declare non-recursive functions, with {} supplied as
  9661 the well-founded relation;
  9662 
  9663 * HOL/Set INCOMPATIBILITY: the complement of set A is now written -A instead of
  9664     Compl A.  The "Compl" syntax remains available as input syntax for this
  9665     release ONLY.
  9666 
  9667 * HOL/Update: new theory of function updates:
  9668     f(a:=b) == %x. if x=a then b else f x
  9669 may also be iterated as in f(a:=b,c:=d,...);
  9670 
  9671 * HOL/Vimage: new theory for inverse image of a function, syntax f-``B;
  9672 
  9673 * HOL/List:
  9674   - new function list_update written xs[i:=v] that updates the i-th
  9675     list position. May also be iterated as in xs[i:=a,j:=b,...].
  9676   - new function `upt' written [i..j(] which generates the list
  9677     [i,i+1,...,j-1], i.e. the upper bound is excluded. To include the upper
  9678     bound write [i..j], which is a shorthand for [i..j+1(].
  9679   - new lexicographic orderings and corresponding wellfoundedness theorems.
  9680 
  9681 * HOL/Arith:
  9682   - removed 'pred' (predecessor) function;
  9683   - generalized some theorems about n-1;
  9684   - many new laws about "div" and "mod";
  9685   - new laws about greatest common divisors (see theory ex/Primes);
  9686 
  9687 * HOL/Relation: renamed the relational operator r^-1 "converse"
  9688 instead of "inverse";
  9689 
  9690 * HOL/Induct/Multiset: a theory of multisets, including the wellfoundedness
  9691   of the multiset ordering;
  9692 
  9693 * directory HOL/Real: a construction of the reals using Dedekind cuts
  9694   (not included by default);
  9695 
  9696 * directory HOL/UNITY: Chandy and Misra's UNITY formalism;
  9697 
  9698 * directory HOL/Hoare: a new version of Hoare logic which permits many-sorted
  9699   programs, i.e. different program variables may have different types.
  9700 
  9701 * calling (stac rew i) now fails if "rew" has no effect on the goal
  9702   [previously, this check worked only if the rewrite rule was unconditional]
  9703   Now rew can involve either definitions or equalities (either == or =).
  9704 
  9705 
  9706 *** ZF ***
  9707 
  9708 * theory Main includes everything; INCOMPATIBILITY: theory ZF.thy contains
  9709   only the theorems proved on ZF.ML;
  9710 
  9711 * ZF INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
  9712   It and 'sym RS equals0D' are now in the default  claset, giving automatic
  9713   disjointness reasoning but breaking a few old proofs.
  9714 
  9715 * ZF/Update: new theory of function updates
  9716     with default rewrite rule  f(x:=y) ` z = if(z=x, y, f`z)
  9717   may also be iterated as in f(a:=b,c:=d,...);
  9718 
  9719 * in  let x=t in u(x), neither t nor u(x) has to be an FOL term.
  9720 
  9721 * calling (stac rew i) now fails if "rew" has no effect on the goal
  9722   [previously, this check worked only if the rewrite rule was unconditional]
  9723   Now rew can involve either definitions or equalities (either == or =).
  9724 
  9725 * case_tac provided for compatibility with HOL
  9726     (like the old excluded_middle_tac, but with subgoals swapped)
  9727 
  9728 
  9729 *** Internal programming interfaces ***
  9730 
  9731 * Pure: several new basic modules made available for general use, see
  9732 also src/Pure/README;
  9733 
  9734 * improved the theory data mechanism to support encapsulation (data
  9735 kind name replaced by private Object.kind, acting as authorization
  9736 key); new type-safe user interface via functor TheoryDataFun; generic
  9737 print_data function becomes basically useless;
  9738 
  9739 * removed global_names compatibility flag -- all theory declarations
  9740 are qualified by default;
  9741 
  9742 * module Pure/Syntax now offers quote / antiquote translation
  9743 functions (useful for Hoare logic etc. with implicit dependencies);
  9744 see HOL/ex/Antiquote for an example use;
  9745 
  9746 * Simplifier now offers conversions (asm_)(full_)rewrite: simpset ->
  9747 cterm -> thm;
  9748 
  9749 * new tactical CHANGED_GOAL for checking that a tactic modifies a
  9750 subgoal;
  9751 
  9752 * Display.print_goals function moved to Locale.print_goals;
  9753 
  9754 * standard print function for goals supports current_goals_markers
  9755 variable for marking begin of proof, end of proof, start of goal; the
  9756 default is ("", "", ""); setting current_goals_markers := ("<proof>",
  9757 "</proof>", "<goal>") causes SGML like tagged proof state printing,
  9758 for example;
  9759 
  9760 
  9761 
  9762 New in Isabelle98 (January 1998)
  9763 --------------------------------
  9764 
  9765 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  9766 
  9767 * changed lexical syntax of terms / types: dots made part of long
  9768 identifiers, e.g. "%x.x" no longer possible, should be "%x. x";
  9769 
  9770 * simpset (and claset) reference variable replaced by functions
  9771 simpset / simpset_ref;
  9772 
  9773 * no longer supports theory aliases (via merge) and non-trivial
  9774 implicit merge of thms' signatures;
  9775 
  9776 * most internal names of constants changed due to qualified names;
  9777 
  9778 * changed Pure/Sequence interface (see Pure/seq.ML);
  9779 
  9780 
  9781 *** General Changes ***
  9782 
  9783 * hierachically structured name spaces (for consts, types, axms, thms
  9784 etc.); new lexical class 'longid' (e.g. Foo.bar.x) may render much of
  9785 old input syntactically incorrect (e.g. "%x.x"); COMPATIBILITY:
  9786 isatool fixdots ensures space after dots (e.g. "%x. x"); set
  9787 long_names for fully qualified output names; NOTE: ML programs
  9788 (special tactics, packages etc.) referring to internal names may have
  9789 to be adapted to cope with fully qualified names; in case of severe
  9790 backward campatibility problems try setting 'global_names' at compile
  9791 time to have enrything declared within a flat name space; one may also
  9792 fine tune name declarations in theories via the 'global' and 'local'
  9793 section;
  9794 
  9795 * reimplemented the implicit simpset and claset using the new anytype
  9796 data filed in signatures; references simpset:simpset ref etc. are
  9797 replaced by functions simpset:unit->simpset and
  9798 simpset_ref:unit->simpset ref; COMPATIBILITY: use isatool fixclasimp
  9799 to patch your ML files accordingly;
  9800 
  9801 * HTML output now includes theory graph data for display with Java
  9802 applet or isatool browser; data generated automatically via isatool
  9803 usedir (see -i option, ISABELLE_USEDIR_OPTIONS);
  9804 
  9805 * defs may now be conditional; improved rewrite_goals_tac to handle
  9806 conditional equations;
  9807 
  9808 * defs now admits additional type arguments, using TYPE('a) syntax;
  9809 
  9810 * theory aliases via merge (e.g. M=A+B+C) no longer supported, always
  9811 creates a new theory node; implicit merge of thms' signatures is
  9812 restricted to 'trivial' ones; COMPATIBILITY: one may have to use
  9813 transfer:theory->thm->thm in (rare) cases;
  9814 
  9815 * improved handling of draft signatures / theories; draft thms (and
  9816 ctyps, cterms) are automatically promoted to real ones;
  9817 
  9818 * slightly changed interfaces for oracles: admit many per theory, named
  9819 (e.g. oracle foo = mlfun), additional name argument for invoke_oracle;
  9820 
  9821 * print_goals: optional output of const types (set show_consts and
  9822 show_types);
  9823 
  9824 * improved output of warnings (###) and errors (***);
  9825 
  9826 * subgoal_tac displays a warning if the new subgoal has type variables;
  9827 
  9828 * removed old README and Makefiles;
  9829 
  9830 * replaced print_goals_ref hook by print_current_goals_fn and result_error_fn;
  9831 
  9832 * removed obsolete init_pps and init_database;
  9833 
  9834 * deleted the obsolete tactical STATE, which was declared by
  9835     fun STATE tacfun st = tacfun st st;
  9836 
  9837 * cd and use now support path variables, e.g. $ISABELLE_HOME, or ~
  9838 (which abbreviates $HOME);
  9839 
  9840 * changed Pure/Sequence interface (see Pure/seq.ML); COMPATIBILITY:
  9841 use isatool fixseq to adapt your ML programs (this works for fully
  9842 qualified references to the Sequence structure only!);
  9843 
  9844 * use_thy no longer requires writable current directory; it always
  9845 reloads .ML *and* .thy file, if either one is out of date;
  9846 
  9847 
  9848 *** Classical Reasoner ***
  9849 
  9850 * Clarify_tac, clarify_tac, clarify_step_tac, Clarify_step_tac: new
  9851 tactics that use classical reasoning to simplify a subgoal without
  9852 splitting it into several subgoals;
  9853 
  9854 * Safe_tac: like safe_tac but uses the default claset;
  9855 
  9856 
  9857 *** Simplifier ***
  9858 
  9859 * added simplification meta rules:
  9860     (asm_)(full_)simplify: simpset -> thm -> thm;
  9861 
  9862 * simplifier.ML no longer part of Pure -- has to be loaded by object
  9863 logics (again);
  9864 
  9865 * added prems argument to simplification procedures;
  9866 
  9867 * HOL, FOL, ZF: added infix function `addsplits':
  9868   instead of `<simpset> setloop (split_tac <thms>)'
  9869   you can simply write `<simpset> addsplits <thms>'
  9870 
  9871 
  9872 *** Syntax ***
  9873 
  9874 * TYPE('a) syntax for type reflection terms;
  9875 
  9876 * no longer handles consts with name "" -- declare as 'syntax' instead;
  9877 
  9878 * pretty printer: changed order of mixfix annotation preference (again!);
  9879 
  9880 * Pure: fixed idt/idts vs. pttrn/pttrns syntactic categories;
  9881 
  9882 
  9883 *** HOL ***
  9884 
  9885 * HOL: there is a new splitter `split_asm_tac' that can be used e.g.
  9886   with `addloop' of the simplifier to faciliate case splitting in premises.
  9887 
  9888 * HOL/TLA: Stephan Merz's formalization of Lamport's Temporal Logic of Actions;
  9889 
  9890 * HOL/Auth: new protocol proofs including some for the Internet
  9891   protocol TLS;
  9892 
  9893 * HOL/Map: new theory of `maps' a la VDM;
  9894 
  9895 * HOL/simplifier: simplification procedures nat_cancel_sums for
  9896 cancelling out common nat summands from =, <, <= (in)equalities, or
  9897 differences; simplification procedures nat_cancel_factor for
  9898 cancelling common factor from =, <, <= (in)equalities over natural
  9899 sums; nat_cancel contains both kinds of procedures, it is installed by
  9900 default in Arith.thy -- this COULD MAKE EXISTING PROOFS FAIL;
  9901 
  9902 * HOL/simplifier: terms of the form
  9903   `? x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x)'  (or t=x)
  9904   are rewritten to
  9905   `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t)',
  9906   and those of the form
  9907   `! x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x) --> R(x)'  (or t=x)
  9908   are rewritten to
  9909   `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t) --> R(t)',
  9910 
  9911 * HOL/datatype
  9912   Each datatype `t' now comes with a theorem `split_t_case' of the form
  9913 
  9914   P(t_case f1 ... fn x) =
  9915      ( (!y1 ... ym1. x = C1 y1 ... ym1 --> P(f1 y1 ... ym1)) &
  9916         ...
  9917        (!y1 ... ymn. x = Cn y1 ... ymn --> P(f1 y1 ... ymn))
  9918      )
  9919 
  9920   and a theorem `split_t_case_asm' of the form
  9921 
  9922   P(t_case f1 ... fn x) =
  9923     ~( (? y1 ... ym1. x = C1 y1 ... ym1 & ~P(f1 y1 ... ym1)) |
  9924         ...
  9925        (? y1 ... ymn. x = Cn y1 ... ymn & ~P(f1 y1 ... ymn))
  9926      )
  9927   which can be added to a simpset via `addsplits'. The existing theorems
  9928   expand_list_case and expand_option_case have been renamed to
  9929   split_list_case and split_option_case.
  9930 
  9931 * HOL/Arithmetic:
  9932   - `pred n' is automatically converted to `n-1'.
  9933     Users are strongly encouraged not to use `pred' any longer,
  9934     because it will disappear altogether at some point.
  9935   - Users are strongly encouraged to write "0 < n" rather than
  9936     "n ~= 0". Theorems and proof tools have been modified towards this
  9937     `standard'.
  9938 
  9939 * HOL/Lists:
  9940   the function "set_of_list" has been renamed "set" (and its theorems too);
  9941   the function "nth" now takes its arguments in the reverse order and
  9942   has acquired the infix notation "!" as in "xs!n".
  9943 
  9944 * HOL/Set: UNIV is now a constant and is no longer translated to Compl{};
  9945 
  9946 * HOL/Set: The operator (UN x.B x) now abbreviates (UN x:UNIV. B x) and its
  9947   specialist theorems (like UN1_I) are gone.  Similarly for (INT x.B x);
  9948 
  9949 * HOL/record: extensible records with schematic structural subtyping
  9950 (single inheritance); EXPERIMENTAL version demonstrating the encoding,
  9951 still lacks various theorems and concrete record syntax;
  9952 
  9953 
  9954 *** HOLCF ***
  9955 
  9956 * removed "axioms" and "generated by" sections;
  9957 
  9958 * replaced "ops" section by extended "consts" section, which is capable of
  9959   handling the continuous function space "->" directly;
  9960 
  9961 * domain package:
  9962   . proves theorems immediately and stores them in the theory,
  9963   . creates hierachical name space,
  9964   . now uses normal mixfix annotations (instead of cinfix...),
  9965   . minor changes to some names and values (for consistency),
  9966   . e.g. cases -> casedist, dists_eq -> dist_eqs, [take_lemma] -> take_lemmas,
  9967   . separator between mutual domain defs: changed "," to "and",
  9968   . improved handling of sort constraints;  now they have to
  9969     appear on the left-hand side of the equations only;
  9970 
  9971 * fixed LAM <x,y,zs>.b syntax;
  9972 
  9973 * added extended adm_tac to simplifier in HOLCF -- can now discharge
  9974 adm (%x. P (t x)), where P is chainfinite and t continuous;
  9975 
  9976 
  9977 *** FOL and ZF ***
  9978 
  9979 * FOL: there is a new splitter `split_asm_tac' that can be used e.g.
  9980   with `addloop' of the simplifier to faciliate case splitting in premises.
  9981 
  9982 * qed_spec_mp, qed_goal_spec_mp, qed_goalw_spec_mp are available, as
  9983 in HOL, they strip ALL and --> from proved theorems;
  9984 
  9985 
  9986 
  9987 New in Isabelle94-8 (May 1997)
  9988 ------------------------------
  9989 
  9990 *** General Changes ***
  9991 
  9992 * new utilities to build / run / maintain Isabelle etc. (in parts
  9993 still somewhat experimental); old Makefiles etc. still functional;
  9994 
  9995 * new 'Isabelle System Manual';
  9996 
  9997 * INSTALL text, together with ./configure and ./build scripts;
  9998 
  9999 * reimplemented type inference for greater efficiency, better error
 10000 messages and clean internal interface;
 10001 
 10002 * prlim command for dealing with lots of subgoals (an easier way of
 10003 setting goals_limit);
 10004 
 10005 
 10006 *** Syntax ***
 10007 
 10008 * supports alternative (named) syntax tables (parser and pretty
 10009 printer); internal interface is provided by add_modesyntax(_i);
 10010 
 10011 * Pure, FOL, ZF, HOL, HOLCF now support symbolic input and output; to
 10012 be used in conjunction with the Isabelle symbol font; uses the
 10013 "symbols" syntax table;
 10014 
 10015 * added token_translation interface (may translate name tokens in
 10016 arbitrary ways, dependent on their type (free, bound, tfree, ...) and
 10017 the current print_mode); IMPORTANT: user print translation functions
 10018 are responsible for marking newly introduced bounds
 10019 (Syntax.mark_boundT);
 10020 
 10021 * token translations for modes "xterm" and "xterm_color" that display
 10022 names in bold, underline etc. or colors (which requires a color
 10023 version of xterm);
 10024 
 10025 * infixes may now be declared with names independent of their syntax;
 10026 
 10027 * added typed_print_translation (like print_translation, but may
 10028 access type of constant);
 10029 
 10030 
 10031 *** Classical Reasoner ***
 10032 
 10033 Blast_tac: a new tactic!  It is often more powerful than fast_tac, but has
 10034 some limitations.  Blast_tac...
 10035   + ignores addss, addbefore, addafter; this restriction is intrinsic
 10036   + ignores elimination rules that don't have the correct format
 10037         (the conclusion MUST be a formula variable)
 10038   + ignores types, which can make HOL proofs fail
 10039   + rules must not require higher-order unification, e.g. apply_type in ZF
 10040     [message "Function Var's argument not a bound variable" relates to this]
 10041   + its proof strategy is more general but can actually be slower
 10042 
 10043 * substitution with equality assumptions no longer permutes other
 10044 assumptions;
 10045 
 10046 * minor changes in semantics of addafter (now called addaltern); renamed
 10047 setwrapper to setWrapper and compwrapper to compWrapper; added safe wrapper
 10048 (and access functions for it);
 10049 
 10050 * improved combination of classical reasoner and simplifier:
 10051   + functions for handling clasimpsets
 10052   + improvement of addss: now the simplifier is called _after_ the
 10053     safe steps.
 10054   + safe variant of addss called addSss: uses safe simplifications
 10055     _during_ the safe steps. It is more complete as it allows multiple
 10056     instantiations of unknowns (e.g. with slow_tac).
 10057 
 10058 *** Simplifier ***
 10059 
 10060 * added interface for simplification procedures (functions that
 10061 produce *proven* rewrite rules on the fly, depending on current
 10062 redex);
 10063 
 10064 * ordering on terms as parameter (used for ordered rewriting);
 10065 
 10066 * new functions delcongs, deleqcongs, and Delcongs. richer rep_ss;
 10067 
 10068 * the solver is now split into a safe and an unsafe part.
 10069 This should be invisible for the normal user, except that the
 10070 functions setsolver and addsolver have been renamed to setSolver and
 10071 addSolver; added safe_asm_full_simp_tac;
 10072 
 10073 
 10074 *** HOL ***
 10075 
 10076 * a generic induction tactic `induct_tac' which works for all datatypes and
 10077 also for type `nat';
 10078 
 10079 * a generic case distinction tactic `exhaust_tac' which works for all
 10080 datatypes and also for type `nat';
 10081 
 10082 * each datatype comes with a function `size';
 10083 
 10084 * patterns in case expressions allow tuple patterns as arguments to
 10085 constructors, for example `case x of [] => ... | (x,y,z)#ps => ...';
 10086 
 10087 * primrec now also works with type nat;
 10088 
 10089 * recdef: a new declaration form, allows general recursive functions to be
 10090 defined in theory files.  See HOL/ex/Fib, HOL/ex/Primes, HOL/Subst/Unify.
 10091 
 10092 * the constant for negation has been renamed from "not" to "Not" to
 10093 harmonize with FOL, ZF, LK, etc.;
 10094 
 10095 * HOL/ex/LFilter theory of a corecursive "filter" functional for
 10096 infinite lists;
 10097 
 10098 * HOL/Modelcheck demonstrates invocation of model checker oracle;
 10099 
 10100 * HOL/ex/Ring.thy declares cring_simp, which solves equational
 10101 problems in commutative rings, using axiomatic type classes for + and *;
 10102 
 10103 * more examples in HOL/MiniML and HOL/Auth;
 10104 
 10105 * more default rewrite rules for quantifiers, union/intersection;
 10106 
 10107 * a new constant `arbitrary == @x.False';
 10108 
 10109 * HOLCF/IOA replaces old HOL/IOA;
 10110 
 10111 * HOLCF changes: derived all rules and arities
 10112   + axiomatic type classes instead of classes
 10113   + typedef instead of faking type definitions
 10114   + eliminated the internal constants less_fun, less_cfun, UU_fun, UU_cfun etc.
 10115   + new axclasses cpo, chfin, flat with flat < chfin < pcpo < cpo < po
 10116   + eliminated the types void, one, tr
 10117   + use unit lift and bool lift (with translations) instead of one and tr
 10118   + eliminated blift from Lift3.thy (use Def instead of blift)
 10119   all eliminated rules are derived as theorems --> no visible changes ;
 10120 
 10121 
 10122 *** ZF ***
 10123 
 10124 * ZF now has Fast_tac, Simp_tac and Auto_tac.  Union_iff is a now a default
 10125 rewrite rule; this may affect some proofs.  eq_cs is gone but can be put back
 10126 as ZF_cs addSIs [equalityI];
 10127 
 10128 
 10129 
 10130 New in Isabelle94-7 (November 96)
 10131 ---------------------------------
 10132 
 10133 * allowing negative levels (as offsets) in prlev and choplev;
 10134 
 10135 * super-linear speedup for large simplifications;
 10136 
 10137 * FOL, ZF and HOL now use miniscoping: rewriting pushes
 10138 quantifications in as far as possible (COULD MAKE EXISTING PROOFS
 10139 FAIL); can suppress it using the command Delsimps (ex_simps @
 10140 all_simps); De Morgan laws are also now included, by default;
 10141 
 10142 * improved printing of ==>  :  ~:
 10143 
 10144 * new object-logic "Sequents" adds linear logic, while replacing LK
 10145 and Modal (thanks to Sara Kalvala);
 10146 
 10147 * HOL/Auth: correctness proofs for authentication protocols;
 10148 
 10149 * HOL: new auto_tac combines rewriting and classical reasoning (many
 10150 examples on HOL/Auth);
 10151 
 10152 * HOL: new command AddIffs for declaring theorems of the form P=Q to
 10153 the rewriter and classical reasoner simultaneously;
 10154 
 10155 * function uresult no longer returns theorems in "standard" format;
 10156 regain previous version by: val uresult = standard o uresult;
 10157 
 10158 
 10159 
 10160 New in Isabelle94-6
 10161 -------------------
 10162 
 10163 * oracles -- these establish an interface between Isabelle and trusted
 10164 external reasoners, which may deliver results as theorems;
 10165 
 10166 * proof objects (in particular record all uses of oracles);
 10167 
 10168 * Simp_tac, Fast_tac, etc. that refer to implicit simpset / claset;
 10169 
 10170 * "constdefs" section in theory files;
 10171 
 10172 * "primrec" section (HOL) no longer requires names;
 10173 
 10174 * internal type "tactic" now simply "thm -> thm Sequence.seq";
 10175 
 10176 
 10177 
 10178 New in Isabelle94-5
 10179 -------------------
 10180 
 10181 * reduced space requirements;
 10182 
 10183 * automatic HTML generation from theories;
 10184 
 10185 * theory files no longer require "..." (quotes) around most types;
 10186 
 10187 * new examples, including two proofs of the Church-Rosser theorem;
 10188 
 10189 * non-curried (1994) version of HOL is no longer distributed;
 10190 
 10191 
 10192 
 10193 New in Isabelle94-4
 10194 -------------------
 10195 
 10196 * greatly reduced space requirements;
 10197 
 10198 * theory files (.thy) no longer require \...\ escapes at line breaks;
 10199 
 10200 * searchable theorem database (see the section "Retrieving theorems" on
 10201 page 8 of the Reference Manual);
 10202 
 10203 * new examples, including Grabczewski's monumental case study of the
 10204 Axiom of Choice;
 10205 
 10206 * The previous version of HOL renamed to Old_HOL;
 10207 
 10208 * The new version of HOL (previously called CHOL) uses a curried syntax
 10209 for functions.  Application looks like f a b instead of f(a,b);
 10210 
 10211 * Mutually recursive inductive definitions finally work in HOL;
 10212 
 10213 * In ZF, pattern-matching on tuples is now available in all abstractions and
 10214 translates to the operator "split";
 10215 
 10216 
 10217 
 10218 New in Isabelle94-3
 10219 -------------------
 10220 
 10221 * new infix operator, addss, allowing the classical reasoner to
 10222 perform simplification at each step of its search.  Example:
 10223         fast_tac (cs addss ss)
 10224 
 10225 * a new logic, CHOL, the same as HOL, but with a curried syntax
 10226 for functions.  Application looks like f a b instead of f(a,b).  Also pairs
 10227 look like (a,b) instead of <a,b>;
 10228 
 10229 * PLEASE NOTE: CHOL will eventually replace HOL!
 10230 
 10231 * In CHOL, pattern-matching on tuples is now available in all abstractions.
 10232 It translates to the operator "split".  A new theory of integers is available;
 10233 
 10234 * In ZF, integer numerals now denote two's-complement binary integers.
 10235 Arithmetic operations can be performed by rewriting.  See ZF/ex/Bin.ML;
 10236 
 10237 * Many new examples: I/O automata, Church-Rosser theorem, equivalents
 10238 of the Axiom of Choice;
 10239 
 10240 
 10241 
 10242 New in Isabelle94-2
 10243 -------------------
 10244 
 10245 * Significantly faster resolution;
 10246 
 10247 * the different sections in a .thy file can now be mixed and repeated
 10248 freely;
 10249 
 10250 * Database of theorems for FOL, HOL and ZF.  New
 10251 commands including qed, qed_goal and bind_thm store theorems in the database.
 10252 
 10253 * Simple database queries: return a named theorem (get_thm) or all theorems of
 10254 a given theory (thms_of), or find out what theory a theorem was proved in
 10255 (theory_of_thm);
 10256 
 10257 * Bugs fixed in the inductive definition and datatype packages;
 10258 
 10259 * The classical reasoner provides deepen_tac and depth_tac, making FOL_dup_cs
 10260 and HOL_dup_cs obsolete;
 10261 
 10262 * Syntactic ambiguities caused by the new treatment of syntax in Isabelle94-1
 10263 have been removed;
 10264 
 10265 * Simpler definition of function space in ZF;
 10266 
 10267 * new results about cardinal and ordinal arithmetic in ZF;
 10268 
 10269 * 'subtype' facility in HOL for introducing new types as subsets of existing
 10270 types;
 10271 
 10272 :mode=text:wrap=hard:maxLineLen=72: