NEWS
author blanchet
Tue, 08 Feb 2011 16:10:10 +0100
changeset 42591 ab3f6d76fb23
parent 42577 d27950860514
child 42599 2837df4d1c7a
permissions -rw-r--r--
available_provers ~> supported_provers (for clarity)
     1 Isabelle NEWS -- history user-relevant changes
     2 ==============================================
     3 
     4 New in this Isabelle version
     5 ----------------------------
     6 
     7 *** General ***
     8 
     9 * Parallelization of nested Isar proofs is subject to
    10 Goal.parallel_proofs_threshold (default 100).  See also isabelle
    11 usedir option -Q.
    12 
    13 
    14 *** HOL ***
    15 
    16 * Sledgehammer:
    17     sledgehammer available_provers ~> sledgehammer supported_provers
    18     INCOMPATIBILITY.
    19 
    20 
    21 *** Document preparation ***
    22 
    23 * New term style "isub" as ad-hoc conversion of variables x1, y23 into
    24 subscripted form x\<^isub>1, y\<^isub>2\<^isub>3.
    25 
    26 
    27 
    28 New in Isabelle2011 (January 2011)
    29 ----------------------------------
    30 
    31 *** General ***
    32 
    33 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
    34 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
    35 useful tooltips and hyperlinks produced from its static analysis.  The
    36 bundled component provides an executable Isabelle tool that can be run
    37 like this:
    38 
    39   Isabelle2011/bin/isabelle jedit
    40 
    41 * Significantly improved Isabelle/Isar implementation manual.
    42 
    43 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
    44 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
    45 while the default heap location within that directory lacks that extra
    46 suffix.  This isolates multiple Isabelle installations from each
    47 other, avoiding problems with old settings in new versions.
    48 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
    49 
    50 * Source files are always encoded as UTF-8, instead of old-fashioned
    51 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
    52 the following package declarations:
    53 
    54   \usepackage[utf8]{inputenc}
    55   \usepackage{textcomp}
    56 
    57 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
    58 a Unicode character is treated as a single symbol, not a sequence of
    59 non-ASCII bytes as before.  Since Isabelle/ML string literals may
    60 contain symbols without further backslash escapes, Unicode can now be
    61 used here as well.  Recall that Symbol.explode in ML provides a
    62 consistent view on symbols, while raw explode (or String.explode)
    63 merely give a byte-oriented representation.
    64 
    65 * Theory loader: source files are primarily located via the master
    66 directory of each theory node (where the .thy file itself resides).
    67 The global load path is still partially available as legacy feature.
    68 Minor INCOMPATIBILITY due to subtle change in file lookup: use
    69 explicit paths, relatively to the theory.
    70 
    71 * Special treatment of ML file names has been discontinued.
    72 Historically, optional extensions .ML or .sml were added on demand --
    73 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
    74 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
    75 
    76 * Various options that affect pretty printing etc. are now properly
    77 handled within the context via configuration options, instead of
    78 unsynchronized references or print modes.  There are both ML Config.T
    79 entities and Isar declaration attributes to access these.
    80 
    81   ML (Config.T)                 Isar (attribute)
    82 
    83   eta_contract                  eta_contract
    84   show_brackets                 show_brackets
    85   show_sorts                    show_sorts
    86   show_types                    show_types
    87   show_question_marks           show_question_marks
    88   show_consts                   show_consts
    89   show_abbrevs                  show_abbrevs
    90 
    91   Syntax.ast_trace              syntax_ast_trace
    92   Syntax.ast_stat               syntax_ast_stat
    93   Syntax.ambiguity_level        syntax_ambiguity_level
    94 
    95   Goal_Display.goals_limit      goals_limit
    96   Goal_Display.show_main_goal   show_main_goal
    97 
    98   Method.rule_trace             rule_trace
    99 
   100   Thy_Output.display            thy_output_display
   101   Thy_Output.quotes             thy_output_quotes
   102   Thy_Output.indent             thy_output_indent
   103   Thy_Output.source             thy_output_source
   104   Thy_Output.break              thy_output_break
   105 
   106 Note that corresponding "..._default" references in ML may only be
   107 changed globally at the ROOT session setup, but *not* within a theory.
   108 The option "show_abbrevs" supersedes the former print mode
   109 "no_abbrevs" with inverted meaning.
   110 
   111 * More systematic naming of some configuration options.
   112 INCOMPATIBILITY.
   113 
   114   trace_simp  ~>  simp_trace
   115   debug_simp  ~>  simp_debug
   116 
   117 * Support for real valued configuration options, using simplistic
   118 floating-point notation that coincides with the inner syntax for
   119 float_token.
   120 
   121 * Support for real valued preferences (with approximative PGIP type):
   122 front-ends need to accept "pgint" values in float notation.
   123 INCOMPATIBILITY.
   124 
   125 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
   126 DejaVu Sans.
   127 
   128 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   129 
   130 
   131 *** Pure ***
   132 
   133 * Command 'type_synonym' (with single argument) replaces somewhat
   134 outdated 'types', which is still available as legacy feature for some
   135 time.
   136 
   137 * Command 'nonterminal' (with 'and' separated list of arguments)
   138 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
   139 
   140 * Command 'notepad' replaces former 'example_proof' for
   141 experimentation in Isar without any result.  INCOMPATIBILITY.
   142 
   143 * Locale interpretation commands 'interpret' and 'sublocale' accept
   144 lists of equations to map definitions in a locale to appropriate
   145 entities in the context of the interpretation.  The 'interpretation'
   146 command already provided this functionality.
   147 
   148 * Diagnostic command 'print_dependencies' prints the locale instances
   149 that would be activated if the specified expression was interpreted in
   150 the current context.  Variant "print_dependencies!" assumes a context
   151 without interpretations.
   152 
   153 * Diagnostic command 'print_interps' prints interpretations in proofs
   154 in addition to interpretations in theories.
   155 
   156 * Discontinued obsolete 'global' and 'local' commands to manipulate
   157 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
   158 Sign.root_path and Sign.local_path may be applied directly where this
   159 feature is still required for historical reasons.
   160 
   161 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
   162 'definition' instead.
   163 
   164 * The "prems" fact, which refers to the accidental collection of
   165 foundational premises in the context, is now explicitly marked as
   166 legacy feature and will be discontinued soon.  Consider using "assms"
   167 of the head statement or reference facts by explicit names.
   168 
   169 * Document antiquotations @{class} and @{type} print classes and type
   170 constructors.
   171 
   172 * Document antiquotation @{file} checks file/directory entries within
   173 the local file system.
   174 
   175 
   176 *** HOL ***
   177 
   178 * Coercive subtyping: functions can be declared as coercions and type
   179 inference will add them as necessary upon input of a term.  Theory
   180 Complex_Main declares real :: nat => real and real :: int => real as
   181 coercions. A coercion function f is declared like this:
   182 
   183   declare [[coercion f]]
   184 
   185 To lift coercions through type constructors (e.g. from nat => real to
   186 nat list => real list), map functions can be declared, e.g.
   187 
   188   declare [[coercion_map map]]
   189 
   190 Currently coercion inference is activated only in theories including
   191 real numbers, i.e. descendants of Complex_Main.  This is controlled by
   192 the configuration option "coercion_enabled", e.g. it can be enabled in
   193 other theories like this:
   194 
   195   declare [[coercion_enabled]]
   196 
   197 * Command 'partial_function' provides basic support for recursive
   198 function definitions over complete partial orders.  Concrete instances
   199 are provided for i) the option type, ii) tail recursion on arbitrary
   200 types, and iii) the heap monad of Imperative_HOL.  See
   201 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
   202 for examples.
   203 
   204 * Function package: f.psimps rules are no longer implicitly declared
   205 as [simp].  INCOMPATIBILITY.
   206 
   207 * Datatype package: theorems generated for executable equality (class
   208 "eq") carry proper names and are treated as default code equations.
   209 
   210 * Inductive package: now offers command 'inductive_simps' to
   211 automatically derive instantiated and simplified equations for
   212 inductive predicates, similar to 'inductive_cases'.
   213 
   214 * Command 'enriched_type' allows to register properties of the
   215 functorial structure of types.
   216 
   217 * Improved infrastructure for term evaluation using code generator
   218 techniques, in particular static evaluation conversions.
   219 
   220 * Code generator: Scala (2.8 or higher) has been added to the target
   221 languages.
   222 
   223 * Code generator: globbing constant expressions "*" and "Theory.*"
   224 have been replaced by the more idiomatic "_" and "Theory._".
   225 INCOMPATIBILITY.
   226 
   227 * Code generator: export_code without explicit file declaration prints
   228 to standard output.  INCOMPATIBILITY.
   229 
   230 * Code generator: do not print function definitions for case
   231 combinators any longer.
   232 
   233 * Code generator: simplification with rules determined with
   234 src/Tools/Code/code_simp.ML and method "code_simp".
   235 
   236 * Code generator for records: more idiomatic representation of record
   237 types.  Warning: records are not covered by ancient SML code
   238 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
   239 rep_datatype declaration helps to succeed then:
   240 
   241   record 'a foo = ...
   242   ...
   243   rep_datatype foo_ext ...
   244 
   245 * Records: logical foundation type for records does not carry a
   246 '_type' suffix any longer (obsolete due to authentic syntax).
   247 INCOMPATIBILITY.
   248 
   249 * Quickcheck now by default uses exhaustive testing instead of random
   250 testing.  Random testing can be invoked by "quickcheck [random]",
   251 exhaustive testing by "quickcheck [exhaustive]".
   252 
   253 * Quickcheck instantiates polymorphic types with small finite
   254 datatypes by default. This enables a simple execution mechanism to
   255 handle quantifiers and function equality over the finite datatypes.
   256 
   257 * Quickcheck random generator has been renamed from "code" to
   258 "random".  INCOMPATIBILITY.
   259 
   260 * Quickcheck now has a configurable time limit which is set to 30
   261 seconds by default. This can be changed by adding [timeout = n] to the
   262 quickcheck command. The time limit for Auto Quickcheck is still set
   263 independently.
   264 
   265 * Quickcheck in locales considers interpretations of that locale for
   266 counter example search.
   267 
   268 * Sledgehammer:
   269   - Added "smt" and "remote_smt" provers based on the "smt" proof
   270     method. See the Sledgehammer manual for details ("isabelle doc
   271     sledgehammer").
   272   - Renamed commands:
   273     sledgehammer atp_info ~> sledgehammer running_provers
   274     sledgehammer atp_kill ~> sledgehammer kill_provers
   275     sledgehammer available_atps ~> sledgehammer available_provers
   276     INCOMPATIBILITY.
   277   - Renamed options:
   278     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
   279     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
   280     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
   281     (and "ms" and "min" are no longer supported)
   282     INCOMPATIBILITY.
   283 
   284 * Nitpick:
   285   - Renamed options:
   286     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
   287     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
   288     INCOMPATIBILITY.
   289   - Added support for partial quotient types.
   290   - Added local versions of the "Nitpick.register_xxx" functions.
   291   - Added "whack" option.
   292   - Allow registration of quotient types as codatatypes.
   293   - Improved "merge_type_vars" option to merge more types.
   294   - Removed unsound "fast_descrs" option.
   295   - Added custom symmetry breaking for datatypes, making it possible to reach
   296     higher cardinalities.
   297   - Prevent the expansion of too large definitions.
   298 
   299 * Proof methods "metis" and "meson" now have configuration options
   300 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
   301 to diagnose these tools. E.g.
   302 
   303     using [[metis_trace = true]]
   304 
   305 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
   306 manually as command 'solve_direct'.
   307 
   308 * The default SMT solver Z3 must be enabled explicitly (due to
   309 licensing issues) by setting the environment variable
   310 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
   311 commercial applications, the SMT solver CVC3 is provided as fall-back;
   312 changing the SMT solver is done via the configuration option
   313 "smt_solver".
   314 
   315 * Remote SMT solvers need to be referred to by the "remote_" prefix,
   316 i.e. "remote_cvc3" and "remote_z3".
   317 
   318 * Added basic SMT support for datatypes, records, and typedefs using
   319 the oracle mode (no proofs).  Direct support of pairs has been dropped
   320 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
   321 support for a similar behavior).  Minor INCOMPATIBILITY.
   322 
   323 * Changed SMT configuration options:
   324   - Renamed:
   325     z3_proofs ~> smt_oracle (with inverted meaning)
   326     z3_trace_assms ~> smt_trace_used_facts
   327     INCOMPATIBILITY.
   328   - Added:
   329     smt_verbose
   330     smt_random_seed
   331     smt_datatypes
   332     smt_infer_triggers
   333     smt_monomorph_limit
   334     cvc3_options
   335     remote_cvc3_options
   336     remote_z3_options
   337     yices_options
   338 
   339 * Boogie output files (.b2i files) need to be declared in the theory
   340 header.
   341 
   342 * Simplification procedure "list_to_set_comprehension" rewrites list
   343 comprehensions applied to List.set to set comprehensions.  Occasional
   344 INCOMPATIBILITY, may be deactivated like this:
   345 
   346   declare [[simproc del: list_to_set_comprehension]]
   347 
   348 * Removed old version of primrec package.  INCOMPATIBILITY.
   349 
   350 * Removed simplifier congruence rule of "prod_case", as has for long
   351 been the case with "split".  INCOMPATIBILITY.
   352 
   353 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
   354 
   355 * Removed [split_format ... and ... and ...] version of
   356 [split_format].  Potential INCOMPATIBILITY.
   357 
   358 * Predicate "sorted" now defined inductively, with nice induction
   359 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
   360 
   361 * Constant "contents" renamed to "the_elem", to free the generic name
   362 contents for other uses.  INCOMPATIBILITY.
   363 
   364 * Renamed class eq and constant eq (for code generation) to class
   365 equal and constant equal, plus renaming of related facts and various
   366 tuning.  INCOMPATIBILITY.
   367 
   368 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
   369 
   370 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
   371 INCOMPATIBILITY.
   372 
   373 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
   374 avoid confusion with finite sets.  INCOMPATIBILITY.
   375 
   376 * Abandoned locales equiv, congruent and congruent2 for equivalence
   377 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
   378 for congruent(2)).
   379 
   380 * Some previously unqualified names have been qualified:
   381 
   382   types
   383     bool ~> HOL.bool
   384     nat ~> Nat.nat
   385 
   386   constants
   387     Trueprop ~> HOL.Trueprop
   388     True ~> HOL.True
   389     False ~> HOL.False
   390     op & ~> HOL.conj
   391     op | ~> HOL.disj
   392     op --> ~> HOL.implies
   393     op = ~> HOL.eq
   394     Not ~> HOL.Not
   395     The ~> HOL.The
   396     All ~> HOL.All
   397     Ex ~> HOL.Ex
   398     Ex1 ~> HOL.Ex1
   399     Let ~> HOL.Let
   400     If ~> HOL.If
   401     Ball ~> Set.Ball
   402     Bex ~> Set.Bex
   403     Suc ~> Nat.Suc
   404     Pair ~> Product_Type.Pair
   405     fst ~> Product_Type.fst
   406     snd ~> Product_Type.snd
   407     curry ~> Product_Type.curry
   408     op : ~> Set.member
   409     Collect ~> Set.Collect
   410 
   411 INCOMPATIBILITY.
   412 
   413 * More canonical naming convention for some fundamental definitions:
   414 
   415     bot_bool_eq ~> bot_bool_def
   416     top_bool_eq ~> top_bool_def
   417     inf_bool_eq ~> inf_bool_def
   418     sup_bool_eq ~> sup_bool_def
   419     bot_fun_eq  ~> bot_fun_def
   420     top_fun_eq  ~> top_fun_def
   421     inf_fun_eq  ~> inf_fun_def
   422     sup_fun_eq  ~> sup_fun_def
   423 
   424 INCOMPATIBILITY.
   425 
   426 * More stylized fact names:
   427 
   428   expand_fun_eq ~> fun_eq_iff
   429   expand_set_eq ~> set_eq_iff
   430   set_ext       ~> set_eqI
   431   nat_number    ~> eval_nat_numeral
   432 
   433 INCOMPATIBILITY.
   434 
   435 * Refactoring of code-generation specific operations in theory List:
   436 
   437   constants
   438     null ~> List.null
   439 
   440   facts
   441     mem_iff ~> member_def
   442     null_empty ~> null_def
   443 
   444 INCOMPATIBILITY.  Note that these were not supposed to be used
   445 regularly unless for striking reasons; their main purpose was code
   446 generation.
   447 
   448 Various operations from the Haskell prelude are used for generating
   449 Haskell code.
   450 
   451 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
   452 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
   453 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
   454 
   455 * Abolished some non-alphabetic type names: "prod" and "sum" replace
   456 "*" and "+" respectively.  INCOMPATIBILITY.
   457 
   458 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
   459 "Sum_Type.Plus" instead.
   460 
   461 * Constant "split" has been merged with constant "prod_case"; names of
   462 ML functions, facts etc. involving split have been retained so far,
   463 though.  INCOMPATIBILITY.
   464 
   465 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
   466 instead.  INCOMPATIBILITY.
   467 
   468 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
   469 INCOMPATIBILITY.
   470 
   471 * Former theory Library/Enum is now part of the HOL-Main image.
   472 INCOMPATIBILITY: all constants of the Enum theory now have to be
   473 referred to by its qualified name.
   474 
   475   enum    ~>  Enum.enum
   476   nlists  ~>  Enum.nlists
   477   product ~>  Enum.product
   478 
   479 * Theory Library/Monad_Syntax provides do-syntax for monad types.
   480 Syntax in Library/State_Monad has been changed to avoid ambiguities.
   481 INCOMPATIBILITY.
   482 
   483 * Theory Library/SetsAndFunctions has been split into
   484 Library/Function_Algebras and Library/Set_Algebras; canonical names
   485 for instance definitions for functions; various improvements.
   486 INCOMPATIBILITY.
   487 
   488 * Theory Library/Multiset provides stable quicksort implementation of
   489 sort_key.
   490 
   491 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
   492 INCOMPATIBILITY.
   493 
   494 * Session Multivariate_Analysis: introduced a type class for euclidean
   495 space.  Most theorems are now stated in terms of euclidean spaces
   496 instead of finite cartesian products.
   497 
   498   types
   499     real ^ 'n ~>  'a::real_vector
   500               ~>  'a::euclidean_space
   501               ~>  'a::ordered_euclidean_space
   502         (depends on your needs)
   503 
   504   constants
   505      _ $ _        ~> _ $$ _
   506      \<chi> x. _  ~> \<chi>\<chi> x. _
   507      CARD('n)     ~> DIM('a)
   508 
   509 Also note that the indices are now natural numbers and not from some
   510 finite type. Finite cartesian products of euclidean spaces, products
   511 of euclidean spaces the real and complex numbers are instantiated to
   512 be euclidean_spaces.  INCOMPATIBILITY.
   513 
   514 * Session Probability: introduced pextreal as positive extended real
   515 numbers.  Use pextreal as value for measures.  Introduce the
   516 Radon-Nikodym derivative, product spaces and Fubini's theorem for
   517 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
   518 the integral in Multivariate Analysis.  INCOMPATIBILITY.
   519 
   520 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   521 INCOMPATIBILITY.
   522 
   523 * Session SPARK (with image HOL-SPARK) provides commands to load and
   524 prove verification conditions generated by the SPARK Ada program
   525 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
   526 
   527 
   528 *** HOL-Algebra ***
   529 
   530 * Theorems for additive ring operations (locale abelian_monoid and
   531 descendants) are generated by interpretation from their multiplicative
   532 counterparts.  Names (in particular theorem names) have the mandatory
   533 qualifier 'add'.  Previous theorem names are redeclared for
   534 compatibility.
   535 
   536 * Structure "int_ring" is now an abbreviation (previously a
   537 definition).  This fits more natural with advanced interpretations.
   538 
   539 
   540 *** HOLCF ***
   541 
   542 * The domain package now runs in definitional mode by default: The
   543 former command 'new_domain' is now called 'domain'.  To use the domain
   544 package in its original axiomatic mode, use 'domain (unsafe)'.
   545 INCOMPATIBILITY.
   546 
   547 * The new class "domain" is now the default sort.  Class "predomain"
   548 is an unpointed version of "domain". Theories can be updated by
   549 replacing sort annotations as shown below.  INCOMPATIBILITY.
   550 
   551   'a::type ~> 'a::countable
   552   'a::cpo  ~> 'a::predomain
   553   'a::pcpo ~> 'a::domain
   554 
   555 * The old type class "rep" has been superseded by class "domain".
   556 Accordingly, users of the definitional package must remove any
   557 "default_sort rep" declarations.  INCOMPATIBILITY.
   558 
   559 * The domain package (definitional mode) now supports unpointed
   560 predomain argument types, as long as they are marked 'lazy'. (Strict
   561 arguments must be in class "domain".) For example, the following
   562 domain definition now works:
   563 
   564   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
   565 
   566 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
   567 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
   568 'a option, and 'a list.  Additionally, it configures fixrec and the
   569 domain package to work with these types.  For example:
   570 
   571   fixrec isInl :: "('a + 'b) u -> tr"
   572     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
   573 
   574   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
   575 
   576 * The "(permissive)" option of fixrec has been replaced with a
   577 per-equation "(unchecked)" option. See
   578 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
   579 
   580 * The "bifinite" class no longer fixes a constant "approx"; the class
   581 now just asserts that such a function exists.  INCOMPATIBILITY.
   582 
   583 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
   584 defines an embedding of type 'a defl into udom by default; instances
   585 of "bifinite" and "domain" classes are available in
   586 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
   587 
   588 * The syntax "REP('a)" has been replaced with "DEFL('a)".
   589 
   590 * The predicate "directed" has been removed.  INCOMPATIBILITY.
   591 
   592 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
   593 
   594 * The function "cprod_map" has been renamed to "prod_map".
   595 INCOMPATIBILITY.
   596 
   597 * The monadic bind operator on each powerdomain has new binder syntax
   598 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
   599 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
   600 
   601 * The infix syntax for binary union on each powerdomain has changed
   602 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
   603 syntax.  INCOMPATIBILITY.
   604 
   605 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
   606 still supported as an input translation.
   607 
   608 * Renamed some theorems (the original names are also still available).
   609 
   610   expand_fun_below   ~> fun_below_iff
   611   below_fun_ext      ~> fun_belowI
   612   expand_cfun_eq     ~> cfun_eq_iff
   613   ext_cfun           ~> cfun_eqI
   614   expand_cfun_below  ~> cfun_below_iff
   615   below_cfun_ext     ~> cfun_belowI
   616   cont2cont_Rep_CFun ~> cont2cont_APP
   617 
   618 * The Abs and Rep functions for various types have changed names.
   619 Related theorem names have also changed to match. INCOMPATIBILITY.
   620 
   621   Rep_CFun  ~> Rep_cfun
   622   Abs_CFun  ~> Abs_cfun
   623   Rep_Sprod ~> Rep_sprod
   624   Abs_Sprod ~> Abs_sprod
   625   Rep_Ssum  ~> Rep_ssum
   626   Abs_Ssum  ~> Abs_ssum
   627 
   628 * Lemmas with names of the form *_defined_iff or *_strict_iff have
   629 been renamed to *_bottom_iff.  INCOMPATIBILITY.
   630 
   631 * Various changes to bisimulation/coinduction with domain package:
   632 
   633   - Definitions of "bisim" constants no longer mention definedness.
   634   - With mutual recursion, "bisim" predicate is now curried.
   635   - With mutual recursion, each type gets a separate coind theorem.
   636   - Variable names in bisim_def and coinduct rules have changed.
   637 
   638 INCOMPATIBILITY.
   639 
   640 * Case combinators generated by the domain package for type "foo" are
   641 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
   642 
   643 * Several theorems have been renamed to more accurately reflect the
   644 names of constants and types involved.  INCOMPATIBILITY.
   645 
   646   thelub_const    ~> lub_const
   647   lub_const       ~> is_lub_const
   648   thelubI         ~> lub_eqI
   649   is_lub_lub      ~> is_lubD2
   650   lubI            ~> is_lub_lub
   651   unique_lub      ~> is_lub_unique
   652   is_ub_lub       ~> is_lub_rangeD1
   653   lub_bin_chain   ~> is_lub_bin_chain
   654   lub_fun         ~> is_lub_fun
   655   thelub_fun      ~> lub_fun
   656   thelub_cfun     ~> lub_cfun
   657   thelub_Pair     ~> lub_Pair
   658   lub_cprod       ~> is_lub_prod
   659   thelub_cprod    ~> lub_prod
   660   minimal_cprod   ~> minimal_prod
   661   inst_cprod_pcpo ~> inst_prod_pcpo
   662   UU_I            ~> bottomI
   663   compact_UU      ~> compact_bottom
   664   deflation_UU    ~> deflation_bottom
   665   finite_deflation_UU ~> finite_deflation_bottom
   666 
   667 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
   668 
   669   sq_ord_less_eq_trans ~> below_eq_trans
   670   sq_ord_eq_less_trans ~> eq_below_trans
   671   refl_less            ~> below_refl
   672   trans_less           ~> below_trans
   673   antisym_less         ~> below_antisym
   674   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
   675   box_less             ~> box_below
   676   rev_trans_less       ~> rev_below_trans
   677   not_less2not_eq      ~> not_below2not_eq
   678   less_UU_iff          ~> below_UU_iff
   679   flat_less_iff        ~> flat_below_iff
   680   adm_less             ~> adm_below
   681   adm_not_less         ~> adm_not_below
   682   adm_compact_not_less ~> adm_compact_not_below
   683   less_fun_def         ~> below_fun_def
   684   expand_fun_less      ~> fun_below_iff
   685   less_fun_ext         ~> fun_belowI
   686   less_discr_def       ~> below_discr_def
   687   discr_less_eq        ~> discr_below_eq
   688   less_unit_def        ~> below_unit_def
   689   less_cprod_def       ~> below_prod_def
   690   prod_lessI           ~> prod_belowI
   691   Pair_less_iff        ~> Pair_below_iff
   692   fst_less_iff         ~> fst_below_iff
   693   snd_less_iff         ~> snd_below_iff
   694   expand_cfun_less     ~> cfun_below_iff
   695   less_cfun_ext        ~> cfun_belowI
   696   injection_less       ~> injection_below
   697   less_up_def          ~> below_up_def
   698   not_Iup_less         ~> not_Iup_below
   699   Iup_less             ~> Iup_below
   700   up_less              ~> up_below
   701   Def_inject_less_eq   ~> Def_below_Def
   702   Def_less_is_eq       ~> Def_below_iff
   703   spair_less_iff       ~> spair_below_iff
   704   less_sprod           ~> below_sprod
   705   spair_less           ~> spair_below
   706   sfst_less_iff        ~> sfst_below_iff
   707   ssnd_less_iff        ~> ssnd_below_iff
   708   fix_least_less       ~> fix_least_below
   709   dist_less_one        ~> dist_below_one
   710   less_ONE             ~> below_ONE
   711   ONE_less_iff         ~> ONE_below_iff
   712   less_sinlD           ~> below_sinlD
   713   less_sinrD           ~> below_sinrD
   714 
   715 
   716 *** FOL and ZF ***
   717 
   718 * All constant names are now qualified internally and use proper
   719 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
   720 
   721 
   722 *** ML ***
   723 
   724 * Antiquotation @{assert} inlines a function bool -> unit that raises
   725 Fail if the argument is false.  Due to inlining the source position of
   726 failed assertions is included in the error output.
   727 
   728 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
   729 text is in practice always evaluated with a stable theory checkpoint.
   730 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
   731 
   732 * Antiquotation @{theory A} refers to theory A from the ancestry of
   733 the current context, not any accidental theory loader state as before.
   734 Potential INCOMPATIBILITY, subtle change in semantics.
   735 
   736 * Syntax.pretty_priority (default 0) configures the required priority
   737 of pretty-printed output and thus affects insertion of parentheses.
   738 
   739 * Syntax.default_root (default "any") configures the inner syntax
   740 category (nonterminal symbol) for parsing of terms.
   741 
   742 * Former exception Library.UnequalLengths now coincides with
   743 ListPair.UnequalLengths.
   744 
   745 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
   746 main functionality is provided by structure Simplifier.
   747 
   748 * Renamed raw "explode" function to "raw_explode" to emphasize its
   749 meaning.  Note that internally to Isabelle, Symbol.explode is used in
   750 almost all situations.
   751 
   752 * Discontinued obsolete function sys_error and exception SYS_ERROR.
   753 See implementation manual for further details on exceptions in
   754 Isabelle/ML.
   755 
   756 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
   757 meaning.
   758 
   759 * Renamed structure PureThy to Pure_Thy and moved most of its
   760 operations to structure Global_Theory, to emphasize that this is
   761 rarely-used global-only stuff.
   762 
   763 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
   764 instead (or tracing for high-volume output).
   765 
   766 * Configuration option show_question_marks only affects regular pretty
   767 printing of types and terms, not raw Term.string_of_vname.
   768 
   769 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
   770 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
   771 @{thms} for most purposes.
   772 
   773 * ML structure Unsynchronized is never opened, not even in Isar
   774 interaction mode as before.  Old Unsynchronized.set etc. have been
   775 discontinued -- use plain := instead.  This should be *rare* anyway,
   776 since modern tools always work via official context data, notably
   777 configuration options.
   778 
   779 * Parallel and asynchronous execution requires special care concerning
   780 interrupts.  Structure Exn provides some convenience functions that
   781 avoid working directly with raw Interrupt.  User code must not absorb
   782 interrupts -- intermediate handling (for cleanup etc.) needs to be
   783 followed by re-raising of the original exception.  Another common
   784 source of mistakes are "handle _" patterns, which make the meaning of
   785 the program subject to physical effects of the environment.
   786 
   787 
   788 
   789 New in Isabelle2009-2 (June 2010)
   790 ---------------------------------
   791 
   792 *** General ***
   793 
   794 * Authentic syntax for *all* logical entities (type classes, type
   795 constructors, term constants): provides simple and robust
   796 correspondence between formal entities and concrete syntax.  Within
   797 the parse tree / AST representations, "constants" are decorated by
   798 their category (class, type, const) and spelled out explicitly with
   799 their full internal name.
   800 
   801 Substantial INCOMPATIBILITY concerning low-level syntax declarations
   802 and translations (translation rules and translation functions in ML).
   803 Some hints on upgrading:
   804 
   805   - Many existing uses of 'syntax' and 'translations' can be replaced
   806     by more modern 'type_notation', 'notation' and 'abbreviation',
   807     which are independent of this issue.
   808 
   809   - 'translations' require markup within the AST; the term syntax
   810     provides the following special forms:
   811 
   812       CONST c   -- produces syntax version of constant c from context
   813       XCONST c  -- literally c, checked as constant from context
   814       c         -- literally c, if declared by 'syntax'
   815 
   816     Plain identifiers are treated as AST variables -- occasionally the
   817     system indicates accidental variables via the error "rhs contains
   818     extra variables".
   819 
   820     Type classes and type constructors are marked according to their
   821     concrete syntax.  Some old translations rules need to be written
   822     for the "type" category, using type constructor application
   823     instead of pseudo-term application of the default category
   824     "logic".
   825 
   826   - 'parse_translation' etc. in ML may use the following
   827     antiquotations:
   828 
   829       @{class_syntax c}   -- type class c within parse tree / AST
   830       @{term_syntax c}    -- type constructor c within parse tree / AST
   831       @{const_syntax c}   -- ML version of "CONST c" above
   832       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
   833 
   834   - Literal types within 'typed_print_translations', i.e. those *not*
   835     represented as pseudo-terms are represented verbatim.  Use @{class
   836     c} or @{type_name c} here instead of the above syntax
   837     antiquotations.
   838 
   839 Note that old non-authentic syntax was based on unqualified base
   840 names, so all of the above "constant" names would coincide.  Recall
   841 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
   842 diagnose syntax problems.
   843 
   844 * Type constructors admit general mixfix syntax, not just infix.
   845 
   846 * Concrete syntax may be attached to local entities without a proof
   847 body, too.  This works via regular mixfix annotations for 'fix',
   848 'def', 'obtain' etc. or via the explicit 'write' command, which is
   849 similar to the 'notation' command in theory specifications.
   850 
   851 * Discontinued unnamed infix syntax (legacy feature for many years) --
   852 need to specify constant name and syntax separately.  Internal ML
   853 datatype constructors have been renamed from InfixName to Infix etc.
   854 Minor INCOMPATIBILITY.
   855 
   856 * Schematic theorem statements need to be explicitly markup as such,
   857 via commands 'schematic_lemma', 'schematic_theorem',
   858 'schematic_corollary'.  Thus the relevance of the proof is made
   859 syntactically clear, which impacts performance in a parallel or
   860 asynchronous interactive environment.  Minor INCOMPATIBILITY.
   861 
   862 * Use of cumulative prems via "!" in some proof methods has been
   863 discontinued (old legacy feature).
   864 
   865 * References 'trace_simp' and 'debug_simp' have been replaced by
   866 configuration options stored in the context. Enabling tracing (the
   867 case of debugging is similar) in proofs works via
   868 
   869   using [[trace_simp = true]]
   870 
   871 Tracing is then active for all invocations of the simplifier in
   872 subsequent goal refinement steps. Tracing may also still be enabled or
   873 disabled via the ProofGeneral settings menu.
   874 
   875 * Separate commands 'hide_class', 'hide_type', 'hide_const',
   876 'hide_fact' replace the former 'hide' KIND command.  Minor
   877 INCOMPATIBILITY.
   878 
   879 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
   880 more efficient than combinations with -q1 or -q2.
   881 
   882 
   883 *** Pure ***
   884 
   885 * Proofterms record type-class reasoning explicitly, using the
   886 "unconstrain" operation internally.  This eliminates all sort
   887 constraints from a theorem and proof, introducing explicit
   888 OFCLASS-premises.  On the proof term level, this operation is
   889 automatically applied at theorem boundaries, such that closed proofs
   890 are always free of sort constraints.  INCOMPATIBILITY for tools that
   891 inspect proof terms.
   892 
   893 * Local theory specifications may depend on extra type variables that
   894 are not present in the result type -- arguments TYPE('a) :: 'a itself
   895 are added internally.  For example:
   896 
   897   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
   898 
   899 * Predicates of locales introduced by classes carry a mandatory
   900 "class" prefix.  INCOMPATIBILITY.
   901 
   902 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
   903 
   904 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
   905 'class' instead.
   906 
   907 * Command 'code_reflect' allows to incorporate generated ML code into
   908 runtime environment; replaces immature code_datatype antiquotation.
   909 INCOMPATIBILITY.
   910 
   911 * Code generator: simple concept for abstract datatypes obeying
   912 invariants.
   913 
   914 * Code generator: details of internal data cache have no impact on the
   915 user space functionality any longer.
   916 
   917 * Methods "unfold_locales" and "intro_locales" ignore non-locale
   918 subgoals.  This is more appropriate for interpretations with 'where'.
   919 INCOMPATIBILITY.
   920 
   921 * Command 'example_proof' opens an empty proof body.  This allows to
   922 experiment with Isar, without producing any persistent result.
   923 
   924 * Commands 'type_notation' and 'no_type_notation' declare type syntax
   925 within a local theory context, with explicit checking of the
   926 constructors involved (in contrast to the raw 'syntax' versions).
   927 
   928 * Commands 'types' and 'typedecl' now work within a local theory
   929 context -- without introducing dependencies on parameters or
   930 assumptions, which is not possible in Isabelle/Pure.
   931 
   932 * Command 'defaultsort' has been renamed to 'default_sort', it works
   933 within a local theory context.  Minor INCOMPATIBILITY.
   934 
   935 
   936 *** HOL ***
   937 
   938 * Command 'typedef' now works within a local theory context -- without
   939 introducing dependencies on parameters or assumptions, which is not
   940 possible in Isabelle/Pure/HOL.  Note that the logical environment may
   941 contain multiple interpretations of local typedefs (with different
   942 non-emptiness proofs), even in a global theory context.
   943 
   944 * New package for quotient types.  Commands 'quotient_type' and
   945 'quotient_definition' may be used for defining types and constants by
   946 quotient constructions.  An example is the type of integers created by
   947 quotienting pairs of natural numbers:
   948 
   949   fun
   950     intrel :: "(nat * nat) => (nat * nat) => bool"
   951   where
   952     "intrel (x, y) (u, v) = (x + v = u + y)"
   953 
   954   quotient_type int = "nat * nat" / intrel
   955     by (auto simp add: equivp_def expand_fun_eq)
   956 
   957   quotient_definition
   958     "0::int" is "(0::nat, 0::nat)"
   959 
   960 The method "lifting" can be used to lift of theorems from the
   961 underlying "raw" type to the quotient type.  The example
   962 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
   963 construction and provides a reasoning infrastructure for finite sets.
   964 
   965 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
   966 clash with new theory Quotient in Main HOL.
   967 
   968 * Moved the SMT binding into the main HOL session, eliminating
   969 separate HOL-SMT session.
   970 
   971 * List membership infix mem operation is only an input abbreviation.
   972 INCOMPATIBILITY.
   973 
   974 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
   975 for future developements; former Library/Word.thy is still present in
   976 the AFP entry RSAPPS.
   977 
   978 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
   979 longer shadowed.  INCOMPATIBILITY.
   980 
   981 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
   982 INCOMPATIBILITY.
   983 
   984 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
   985 INCOMPATIBILITY.
   986 
   987 * Dropped normalizing_semiring etc; use the facts in semiring classes
   988 instead.  INCOMPATIBILITY.
   989 
   990 * Dropped several real-specific versions of lemmas about floor and
   991 ceiling; use the generic lemmas from theory "Archimedean_Field"
   992 instead.  INCOMPATIBILITY.
   993 
   994   floor_number_of_eq         ~> floor_number_of
   995   le_floor_eq_number_of      ~> number_of_le_floor
   996   le_floor_eq_zero           ~> zero_le_floor
   997   le_floor_eq_one            ~> one_le_floor
   998   floor_less_eq_number_of    ~> floor_less_number_of
   999   floor_less_eq_zero         ~> floor_less_zero
  1000   floor_less_eq_one          ~> floor_less_one
  1001   less_floor_eq_number_of    ~> number_of_less_floor
  1002   less_floor_eq_zero         ~> zero_less_floor
  1003   less_floor_eq_one          ~> one_less_floor
  1004   floor_le_eq_number_of      ~> floor_le_number_of
  1005   floor_le_eq_zero           ~> floor_le_zero
  1006   floor_le_eq_one            ~> floor_le_one
  1007   floor_subtract_number_of   ~> floor_diff_number_of
  1008   floor_subtract_one         ~> floor_diff_one
  1009   ceiling_number_of_eq       ~> ceiling_number_of
  1010   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  1011   ceiling_le_zero_eq         ~> ceiling_le_zero
  1012   ceiling_le_eq_one          ~> ceiling_le_one
  1013   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  1014   less_ceiling_eq_zero       ~> zero_less_ceiling
  1015   less_ceiling_eq_one        ~> one_less_ceiling
  1016   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  1017   ceiling_less_eq_zero       ~> ceiling_less_zero
  1018   ceiling_less_eq_one        ~> ceiling_less_one
  1019   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  1020   le_ceiling_eq_zero         ~> zero_le_ceiling
  1021   le_ceiling_eq_one          ~> one_le_ceiling
  1022   ceiling_subtract_number_of ~> ceiling_diff_number_of
  1023   ceiling_subtract_one       ~> ceiling_diff_one
  1024 
  1025 * Theory "Finite_Set": various folding_XXX locales facilitate the
  1026 application of the various fold combinators on finite sets.
  1027 
  1028 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  1029 provides abstract red-black tree type which is backed by "RBT_Impl" as
  1030 implementation.  INCOMPATIBILTY.
  1031 
  1032 * Theory Library/Coinductive_List has been removed -- superseded by
  1033 AFP/thys/Coinductive.
  1034 
  1035 * Theory PReal, including the type "preal" and related operations, has
  1036 been removed.  INCOMPATIBILITY.
  1037 
  1038 * Real: new development using Cauchy Sequences.
  1039 
  1040 * Split off theory "Big_Operators" containing setsum, setprod,
  1041 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  1042 
  1043 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  1044 "Int" etc.  INCOMPATIBILITY.
  1045 
  1046 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  1047 
  1048 * New set of rules "ac_simps" provides combined assoc / commute
  1049 rewrites for all interpretations of the appropriate generic locales.
  1050 
  1051 * Renamed theory "OrderedGroup" to "Groups" and split theory
  1052 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  1053 appropriate and more consistent names suitable for name prefixes
  1054 within the HOL theories.  INCOMPATIBILITY.
  1055 
  1056 * Some generic constants have been put to appropriate theories:
  1057   - less_eq, less: Orderings
  1058   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  1059   - inverse, divide: Rings
  1060 INCOMPATIBILITY.
  1061 
  1062 * More consistent naming of type classes involving orderings (and
  1063 lattices):
  1064 
  1065     lower_semilattice                   ~> semilattice_inf
  1066     upper_semilattice                   ~> semilattice_sup
  1067 
  1068     dense_linear_order                  ~> dense_linorder
  1069 
  1070     pordered_ab_group_add               ~> ordered_ab_group_add
  1071     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  1072     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  1073     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  1074     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  1075     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  1076     pordered_cancel_semiring            ~> ordered_cancel_semiring
  1077     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  1078     pordered_comm_ring                  ~> ordered_comm_ring
  1079     pordered_comm_semiring              ~> ordered_comm_semiring
  1080     pordered_ring                       ~> ordered_ring
  1081     pordered_ring_abs                   ~> ordered_ring_abs
  1082     pordered_semiring                   ~> ordered_semiring
  1083 
  1084     ordered_ab_group_add                ~> linordered_ab_group_add
  1085     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  1086     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  1087     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  1088     ordered_field                       ~> linordered_field
  1089     ordered_field_no_lb                 ~> linordered_field_no_lb
  1090     ordered_field_no_ub                 ~> linordered_field_no_ub
  1091     ordered_field_dense_linear_order    ~> dense_linordered_field
  1092     ordered_idom                        ~> linordered_idom
  1093     ordered_ring                        ~> linordered_ring
  1094     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  1095     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  1096     ordered_ring_strict                 ~> linordered_ring_strict
  1097     ordered_semidom                     ~> linordered_semidom
  1098     ordered_semiring                    ~> linordered_semiring
  1099     ordered_semiring_1                  ~> linordered_semiring_1
  1100     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  1101     ordered_semiring_strict             ~> linordered_semiring_strict
  1102 
  1103   The following slightly odd type classes have been moved to a
  1104   separate theory Library/Lattice_Algebras:
  1105 
  1106     lordered_ab_group_add               ~> lattice_ab_group_add
  1107     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  1108     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  1109     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  1110     lordered_ring                       ~> lattice_ring
  1111 
  1112 INCOMPATIBILITY.
  1113 
  1114 * Refined field classes:
  1115   - classes division_ring_inverse_zero, field_inverse_zero,
  1116     linordered_field_inverse_zero include rule inverse 0 = 0 --
  1117     subsumes former division_by_zero class;
  1118   - numerous lemmas have been ported from field to division_ring.
  1119 INCOMPATIBILITY.
  1120 
  1121 * Refined algebra theorem collections:
  1122   - dropped theorem group group_simps, use algebra_simps instead;
  1123   - dropped theorem group ring_simps, use field_simps instead;
  1124   - proper theorem collection field_simps subsumes former theorem
  1125     groups field_eq_simps and field_simps;
  1126   - dropped lemma eq_minus_self_iff which is a duplicate for
  1127     equal_neg_zero.
  1128 INCOMPATIBILITY.
  1129 
  1130 * Theory Finite_Set and List: some lemmas have been generalized from
  1131 sets to lattices:
  1132 
  1133   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  1134   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  1135   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  1136   union_Union_fold_union        ~> sup_Sup_fold_sup
  1137   Inter_fold_inter              ~> Inf_fold_inf
  1138   Union_fold_union              ~> Sup_fold_sup
  1139   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  1140   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  1141   INTER_fold_inter              ~> INFI_fold_inf
  1142   UNION_fold_union              ~> SUPR_fold_sup
  1143 
  1144 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  1145 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  1146 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  1147 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  1148 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  1149 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  1150 
  1151 * Reorganized theory Multiset: swapped notation of pointwise and
  1152 multiset order:
  1153 
  1154   - pointwise ordering is instance of class order with standard syntax
  1155     <= and <;
  1156   - multiset ordering has syntax <=# and <#; partial order properties
  1157     are provided by means of interpretation with prefix
  1158     multiset_order;
  1159   - less duplication, less historical organization of sections,
  1160     conversion from associations lists to multisets, rudimentary code
  1161     generation;
  1162   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  1163     if needed.
  1164 
  1165 Renamed:
  1166 
  1167   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  1168   multi_count_ext  ~>  multiset_ext
  1169   diff_union_inverse2  ~>  diff_union_cancelR
  1170 
  1171 INCOMPATIBILITY.
  1172 
  1173 * Theory Permutation: replaced local "remove" by List.remove1.
  1174 
  1175 * Code generation: ML and OCaml code is decorated with signatures.
  1176 
  1177 * Theory List: added transpose.
  1178 
  1179 * Library/Nat_Bijection.thy is a collection of bijective functions
  1180 between nat and other types, which supersedes the older libraries
  1181 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  1182 
  1183   Constants:
  1184   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  1185   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  1186   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  1187   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  1188   Countable.pair_encode           ~> prod_encode
  1189   NatIso.prod2nat                 ~> prod_encode
  1190   NatIso.nat2prod                 ~> prod_decode
  1191   NatIso.sum2nat                  ~> sum_encode
  1192   NatIso.nat2sum                  ~> sum_decode
  1193   NatIso.list2nat                 ~> list_encode
  1194   NatIso.nat2list                 ~> list_decode
  1195   NatIso.set2nat                  ~> set_encode
  1196   NatIso.nat2set                  ~> set_decode
  1197 
  1198   Lemmas:
  1199   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  1200   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  1201   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  1202   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  1203   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  1204   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  1205   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  1206   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  1207   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  1208   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  1209   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  1210   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  1211   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  1212 
  1213 * Sledgehammer:
  1214   - Renamed ATP commands:
  1215     atp_info     ~> sledgehammer running_atps
  1216     atp_kill     ~> sledgehammer kill_atps
  1217     atp_messages ~> sledgehammer messages
  1218     atp_minimize ~> sledgehammer minimize
  1219     print_atps   ~> sledgehammer available_atps
  1220     INCOMPATIBILITY.
  1221   - Added user's manual ("isabelle doc sledgehammer").
  1222   - Added option syntax and "sledgehammer_params" to customize
  1223     Sledgehammer's behavior.  See the manual for details.
  1224   - Modified the Isar proof reconstruction code so that it produces
  1225     direct proofs rather than proofs by contradiction.  (This feature
  1226     is still experimental.)
  1227   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  1228     full-typed mode.
  1229   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  1230 
  1231 * Nitpick:
  1232   - Added and implemented "binary_ints" and "bits" options.
  1233   - Added "std" option and implemented support for nonstandard models.
  1234   - Added and implemented "finitize" option to improve the precision
  1235     of infinite datatypes based on a monotonicity analysis.
  1236   - Added support for quotient types.
  1237   - Added support for "specification" and "ax_specification"
  1238     constructs.
  1239   - Added support for local definitions (for "function" and
  1240     "termination" proofs).
  1241   - Added support for term postprocessors.
  1242   - Optimized "Multiset.multiset" and "FinFun.finfun".
  1243   - Improved efficiency of "destroy_constrs" optimization.
  1244   - Fixed soundness bugs related to "destroy_constrs" optimization and
  1245     record getters.
  1246   - Fixed soundness bug related to higher-order constructors.
  1247   - Fixed soundness bug when "full_descrs" is enabled.
  1248   - Improved precision of set constructs.
  1249   - Added "atoms" option.
  1250   - Added cache to speed up repeated Kodkod invocations on the same
  1251     problems.
  1252   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  1253     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  1254     "SAT4J_Light".  INCOMPATIBILITY.
  1255   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  1256     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  1257   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  1258 
  1259 * Method "induct" now takes instantiations of the form t, where t is not
  1260   a variable, as a shorthand for "x == t", where x is a fresh variable.
  1261   If this is not intended, t has to be enclosed in parentheses.
  1262   By default, the equalities generated by definitional instantiations
  1263   are pre-simplified, which may cause parameters of inductive cases
  1264   to disappear, or may even delete some of the inductive cases.
  1265   Use "induct (no_simp)" instead of "induct" to restore the old
  1266   behaviour. The (no_simp) option is also understood by the "cases"
  1267   and "nominal_induct" methods, which now perform pre-simplification, too.
  1268   INCOMPATIBILITY.
  1269 
  1270 
  1271 *** HOLCF ***
  1272 
  1273 * Variable names in lemmas generated by the domain package have
  1274 changed; the naming scheme is now consistent with the HOL datatype
  1275 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  1276 
  1277 * The domain package no longer defines the function "foo_copy" for
  1278 recursive domain "foo".  The reach lemma is now stated directly in
  1279 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  1280 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  1281 
  1282 * Most definedness lemmas generated by the domain package (previously
  1283 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  1284 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  1285 Proofs that used definedness lemmas as intro rules may break,
  1286 potential INCOMPATIBILITY.
  1287 
  1288 * Induction and casedist rules generated by the domain package now
  1289 declare proper case_names (one called "bottom", and one named for each
  1290 constructor).  INCOMPATIBILITY.
  1291 
  1292 * For mutually-recursive domains, separate "reach" and "take_lemma"
  1293 rules are generated for each domain, INCOMPATIBILITY.
  1294 
  1295   foo_bar.reach       ~> foo.reach  bar.reach
  1296   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  1297 
  1298 * Some lemmas generated by the domain package have been renamed for
  1299 consistency with the datatype package, INCOMPATIBILITY.
  1300 
  1301   foo.ind        ~> foo.induct
  1302   foo.finite_ind ~> foo.finite_induct
  1303   foo.coind      ~> foo.coinduct
  1304   foo.casedist   ~> foo.exhaust
  1305   foo.exhaust    ~> foo.nchotomy
  1306 
  1307 * For consistency with other definition packages, the fixrec package
  1308 now generates qualified theorem names, INCOMPATIBILITY.
  1309 
  1310   foo_simps  ~> foo.simps
  1311   foo_unfold ~> foo.unfold
  1312   foo_induct ~> foo.induct
  1313 
  1314 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  1315 method and internal fixrec proofs now use the default simpset instead.
  1316 INCOMPATIBILITY.
  1317 
  1318 * The "contlub" predicate has been removed.  Proof scripts should use
  1319 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  1320 
  1321 * The "admw" predicate has been removed, INCOMPATIBILITY.
  1322 
  1323 * The constants cpair, cfst, and csnd have been removed in favor of
  1324 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  1325 
  1326 
  1327 *** ML ***
  1328 
  1329 * Antiquotations for basic formal entities:
  1330 
  1331     @{class NAME}         -- type class
  1332     @{class_syntax NAME}  -- syntax representation of the above
  1333 
  1334     @{type_name NAME}     -- logical type
  1335     @{type_abbrev NAME}   -- type abbreviation
  1336     @{nonterminal NAME}   -- type of concrete syntactic category
  1337     @{type_syntax NAME}   -- syntax representation of any of the above
  1338 
  1339     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  1340     @{const_abbrev NAME}  -- abbreviated constant
  1341     @{const_syntax NAME}  -- syntax representation of any of the above
  1342 
  1343 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  1344 syntax constant (cf. 'syntax' command).
  1345 
  1346 * Antiquotation @{make_string} inlines a function to print arbitrary
  1347 values similar to the ML toplevel.  The result is compiler dependent
  1348 and may fall back on "?" in certain situations.
  1349 
  1350 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  1351 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  1352 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  1353 not work with the asynchronous Isar document model.
  1354 
  1355 * Configuration options now admit dynamic default values, depending on
  1356 the context or even global references.
  1357 
  1358 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  1359 uses an efficient external library if available (for Poly/ML).
  1360 
  1361 * Renamed some important ML structures, while keeping the old names
  1362 for some time as aliases within the structure Legacy:
  1363 
  1364   OuterKeyword  ~>  Keyword
  1365   OuterLex      ~>  Token
  1366   OuterParse    ~>  Parse
  1367   OuterSyntax   ~>  Outer_Syntax
  1368   PrintMode     ~>  Print_Mode
  1369   SpecParse     ~>  Parse_Spec
  1370   ThyInfo       ~>  Thy_Info
  1371   ThyLoad       ~>  Thy_Load
  1372   ThyOutput     ~>  Thy_Output
  1373   TypeInfer     ~>  Type_Infer
  1374 
  1375 Note that "open Legacy" simplifies porting of sources, but forgetting
  1376 to remove it again will complicate porting again in the future.
  1377 
  1378 * Most operations that refer to a global context are named
  1379 accordingly, e.g. Simplifier.global_context or
  1380 ProofContext.init_global.  There are some situations where a global
  1381 context actually works, but under normal circumstances one needs to
  1382 pass the proper local context through the code!
  1383 
  1384 * Discontinued old TheoryDataFun with its copy/init operation -- data
  1385 needs to be pure.  Functor Theory_Data_PP retains the traditional
  1386 Pretty.pp argument to merge, which is absent in the standard
  1387 Theory_Data version.
  1388 
  1389 * Sorts.certify_sort and derived "cert" operations for types and terms
  1390 no longer minimize sorts.  Thus certification at the boundary of the
  1391 inference kernel becomes invariant under addition of class relations,
  1392 which is an important monotonicity principle.  Sorts are now minimized
  1393 in the syntax layer only, at the boundary between the end-user and the
  1394 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  1395 explicitly in rare situations.
  1396 
  1397 * Renamed old-style Drule.standard to Drule.export_without_context, to
  1398 emphasize that this is in no way a standard operation.
  1399 INCOMPATIBILITY.
  1400 
  1401 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  1402 usual for resolution.  Rare INCOMPATIBILITY.
  1403 
  1404 * Renamed varify/unvarify operations to varify_global/unvarify_global
  1405 to emphasize that these only work in a global situation (which is
  1406 quite rare).
  1407 
  1408 * Curried take and drop in library.ML; negative length is interpreted
  1409 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  1410 
  1411 * Proof terms: type substitutions on proof constants now use canonical
  1412 order of type variables.  INCOMPATIBILITY for tools working with proof
  1413 terms.
  1414 
  1415 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  1416 may no longer carry premises.  User-level specifications are
  1417 transformed accordingly by Thm.add_axiom/add_def.
  1418 
  1419 
  1420 *** System ***
  1421 
  1422 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  1423 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  1424 proof terms are enabled unconditionally in the new HOL-Proofs image.
  1425 
  1426 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  1427 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  1428 respectively.
  1429 
  1430 * Old lib/scripts/polyml-platform is superseded by the
  1431 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  1432 variant, even on a 64 bit machine.  The following example setting
  1433 prefers 64 bit if available:
  1434 
  1435   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  1436 
  1437 * The preliminary Isabelle/jEdit application demonstrates the emerging
  1438 Isabelle/Scala layer for advanced prover interaction and integration.
  1439 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  1440 component.
  1441 
  1442 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  1443 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  1444 similar to the default assignment of the document preparation system
  1445 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  1446 provides some operations for direct access to the font without asking
  1447 the user for manual installation.
  1448 
  1449 
  1450 
  1451 New in Isabelle2009-1 (December 2009)
  1452 -------------------------------------
  1453 
  1454 *** General ***
  1455 
  1456 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  1457 one backslash should be used, even in ML sources.
  1458 
  1459 
  1460 *** Pure ***
  1461 
  1462 * Locale interpretation propagates mixins along the locale hierarchy.
  1463 The currently only available mixins are the equations used to map
  1464 local definitions to terms of the target domain of an interpretation.
  1465 
  1466 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  1467 loc" to print all interpretations of locale "loc" in the theory.
  1468 Interpretations in proofs are not shown.
  1469 
  1470 * Thoroughly revised locales tutorial.  New section on conditional
  1471 interpretation.
  1472 
  1473 * On instantiation of classes, remaining undefined class parameters
  1474 are formally declared.  INCOMPATIBILITY.
  1475 
  1476 
  1477 *** Document preparation ***
  1478 
  1479 * New generalized style concept for printing terms: @{foo (style) ...}
  1480 instead of @{foo_style style ...}  (old form is still retained for
  1481 backward compatibility).  Styles can be also applied for
  1482 antiquotations prop, term_type and typeof.
  1483 
  1484 
  1485 *** HOL ***
  1486 
  1487 * New proof method "smt" for a combination of first-order logic with
  1488 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  1489 fixed-size bitvectors; there is also basic support for higher-order
  1490 features (esp. lambda abstractions).  It is an incomplete decision
  1491 procedure based on external SMT solvers using the oracle mechanism;
  1492 for the SMT solver Z3, this method is proof-producing.  Certificates
  1493 are provided to avoid calling the external solvers solely for
  1494 re-checking proofs.  Due to a remote SMT service there is no need for
  1495 installing SMT solvers locally.  See src/HOL/SMT.
  1496 
  1497 * New commands to load and prove verification conditions generated by
  1498 the Boogie program verifier or derived systems (e.g. the Verifying C
  1499 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1500 
  1501 * New counterexample generator tool 'nitpick' based on the Kodkod
  1502 relational model finder.  See src/HOL/Tools/Nitpick and
  1503 src/HOL/Nitpick_Examples.
  1504 
  1505 * New commands 'code_pred' and 'values' to invoke the predicate
  1506 compiler and to enumerate values of inductive predicates.
  1507 
  1508 * A tabled implementation of the reflexive transitive closure.
  1509 
  1510 * New implementation of quickcheck uses generic code generator;
  1511 default generators are provided for all suitable HOL types, records
  1512 and datatypes.  Old quickcheck can be re-activated importing theory
  1513 Library/SML_Quickcheck.
  1514 
  1515 * New testing tool Mirabelle for automated proof tools.  Applies
  1516 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1517 every proof step in a theory.  To be used in batch mode via the
  1518 "mirabelle" utility.
  1519 
  1520 * New proof method "sos" (sum of squares) for nonlinear real
  1521 arithmetic (originally due to John Harison). It requires theory
  1522 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1523 works well in practice on quantifier-free real arithmetic with +, -,
  1524 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1525 inequalities between polynomials.  It makes use of external
  1526 semidefinite programming solvers.  Method "sos" generates a
  1527 certificate that can be pasted into the proof thus avoiding the need
  1528 to call an external tool every time the proof is checked.  See
  1529 src/HOL/Library/Sum_Of_Squares.
  1530 
  1531 * New method "linarith" invokes existing linear arithmetic decision
  1532 procedure only.
  1533 
  1534 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1535 
  1536 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1537 Causes full type information to be output to the ATPs.  This slows
  1538 ATPs down considerably but eliminates a source of unsound "proofs"
  1539 that fail later.
  1540 
  1541 * New method "metisFT": A version of metis that uses full type
  1542 information in order to avoid failures of proof reconstruction.
  1543 
  1544 * New evaluator "approximate" approximates an real valued term using
  1545 the same method as the approximation method.
  1546 
  1547 * Method "approximate" now supports arithmetic expressions as
  1548 boundaries of intervals and implements interval splitting and Taylor
  1549 series expansion.
  1550 
  1551 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1552 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1553 
  1554 * New theory SupInf of the supremum and infimum operators for sets of
  1555 reals.
  1556 
  1557 * New theory Probability, which contains a development of measure
  1558 theory, eventually leading to Lebesgue integration and probability.
  1559 
  1560 * Extended Multivariate Analysis to include derivation and Brouwer's
  1561 fixpoint theorem.
  1562 
  1563 * Reorganization of number theory, INCOMPATIBILITY:
  1564   - new number theory development for nat and int, in theories Divides
  1565     and GCD as well as in new session Number_Theory
  1566   - some constants and facts now suffixed with _nat and _int
  1567     accordingly
  1568   - former session NumberTheory now named Old_Number_Theory, including
  1569     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1570   - moved theory Pocklington from src/HOL/Library to
  1571     src/HOL/Old_Number_Theory
  1572 
  1573 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1574 lcm of finite and infinite sets. It is shown that they form a complete
  1575 lattice.
  1576 
  1577 * Class semiring_div requires superclass no_zero_divisors and proof of
  1578 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1579 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1580 generalized to class semiring_div, subsuming former theorems
  1581 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1582 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1583 INCOMPATIBILITY.
  1584 
  1585 * Refinements to lattice classes and sets:
  1586   - less default intro/elim rules in locale variant, more default
  1587     intro/elim rules in class variant: more uniformity
  1588   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1589     le_inf_iff
  1590   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1591     sup_aci)
  1592   - renamed ACI to inf_sup_aci
  1593   - new class "boolean_algebra"
  1594   - class "complete_lattice" moved to separate theory
  1595     "Complete_Lattice"; corresponding constants (and abbreviations)
  1596     renamed and with authentic syntax:
  1597     Set.Inf ~>    Complete_Lattice.Inf
  1598     Set.Sup ~>    Complete_Lattice.Sup
  1599     Set.INFI ~>   Complete_Lattice.INFI
  1600     Set.SUPR ~>   Complete_Lattice.SUPR
  1601     Set.Inter ~>  Complete_Lattice.Inter
  1602     Set.Union ~>  Complete_Lattice.Union
  1603     Set.INTER ~>  Complete_Lattice.INTER
  1604     Set.UNION ~>  Complete_Lattice.UNION
  1605   - authentic syntax for
  1606     Set.Pow
  1607     Set.image
  1608   - mere abbreviations:
  1609     Set.empty               (for bot)
  1610     Set.UNIV                (for top)
  1611     Set.inter               (for inf, formerly Set.Int)
  1612     Set.union               (for sup, formerly Set.Un)
  1613     Complete_Lattice.Inter  (for Inf)
  1614     Complete_Lattice.Union  (for Sup)
  1615     Complete_Lattice.INTER  (for INFI)
  1616     Complete_Lattice.UNION  (for SUPR)
  1617   - object-logic definitions as far as appropriate
  1618 
  1619 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1620 Un_subset_iff are explicitly deleted as default simp rules; then also
  1621 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1622 deleted to achieve the desired effect.
  1623 
  1624 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1625 rules by default any longer; the same applies to min_max.inf_absorb1
  1626 etc.  INCOMPATIBILITY.
  1627 
  1628 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1629 pred_set_conv by default.  INCOMPATIBILITY.
  1630 
  1631 * Power operations on relations and functions are now one dedicated
  1632 constant "compow" with infix syntax "^^".  Power operation on
  1633 multiplicative monoids retains syntax "^" and is now defined generic
  1634 in class power.  INCOMPATIBILITY.
  1635 
  1636 * Relation composition "R O S" now has a more standard argument order:
  1637 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1638 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1639 break, since the O_assoc rule was not rewritten like this.  Fix using
  1640 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1641 
  1642 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1643 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1644 INCOMPATIBILITY.
  1645 
  1646 * Most rules produced by inductive and datatype package have mandatory
  1647 prefixes.  INCOMPATIBILITY.
  1648 
  1649 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1650 the attribute of the same name.  Each of the theorems in the list
  1651 DERIV_intros assumes composition with an additional function and
  1652 matches a variable to the derivative, which has to be solved by the
  1653 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1654 of most elementary terms.  Former Maclauren.DERIV_tac and
  1655 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1656 INCOMPATIBILITY.
  1657 
  1658 * Code generator attributes follow the usual underscore convention:
  1659     code_unfold     replaces    code unfold
  1660     code_post       replaces    code post
  1661     etc.
  1662   INCOMPATIBILITY.
  1663 
  1664 * Renamed methods:
  1665     sizechange -> size_change
  1666     induct_scheme -> induction_schema
  1667   INCOMPATIBILITY.
  1668 
  1669 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1670 INCOMPATIBILITY, use "undefined" directly.
  1671 
  1672 * Renamed theorems:
  1673     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1674     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1675     Suc_plus1 -> Suc_eq_plus1
  1676     *anti_sym -> *antisym*
  1677     vector_less_eq_def -> vector_le_def
  1678   INCOMPATIBILITY.
  1679 
  1680 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1681 INCOMPATIBILITY.
  1682 
  1683 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1684 INCOMPATIBILITY.
  1685 
  1686 
  1687 *** HOLCF ***
  1688 
  1689 * Theory Representable defines a class "rep" of domains that are
  1690 representable (via an ep-pair) in the universal domain type "udom".
  1691 Instances are provided for all type constructors defined in HOLCF.
  1692 
  1693 * The 'new_domain' command is a purely definitional version of the
  1694 domain package, for representable domains.  Syntax is identical to the
  1695 old domain package.  The 'new_domain' package also supports indirect
  1696 recursion using previously-defined type constructors.  See
  1697 src/HOLCF/ex/New_Domain.thy for examples.
  1698 
  1699 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1700 on the left-hand side of an equation, and then performs
  1701 simplification.  Rewriting is done using rules declared with the
  1702 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1703 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1704 
  1705 * The pattern-match compiler in 'fixrec' can now handle constructors
  1706 with HOL function types.  Pattern-match combinators for the Pair
  1707 constructor are pre-configured.
  1708 
  1709 * The 'fixrec' package now produces better fixed-point induction rules
  1710 for mutually-recursive definitions:  Induction rules have conclusions
  1711 of the form "P foo bar" instead of "P <foo, bar>".
  1712 
  1713 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1714 been renamed to "below".  The name "below" now replaces "less" in many
  1715 theorem names.  (Legacy theorem names using "less" are still supported
  1716 as well.)
  1717 
  1718 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1719 patterns can be used to generate strictness rules, or to make
  1720 functions more strict (much like the bang-patterns supported by the
  1721 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1722 examples.
  1723 
  1724 
  1725 *** ML ***
  1726 
  1727 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1728 errors and run-time exceptions, including detailed source positions.
  1729 
  1730 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1731 identified entries, with some additional information such as source
  1732 position, logical grouping etc.
  1733 
  1734 * Theory and context data is now introduced by the simplified and
  1735 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1736 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1737 copy operation) is still available for some time.
  1738 
  1739 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1740 provides a high-level programming interface to synchronized state
  1741 variables with atomic update.  This works via pure function
  1742 application within a critical section -- its runtime should be as
  1743 short as possible; beware of deadlocks if critical code is nested,
  1744 either directly or indirectly via other synchronized variables!
  1745 
  1746 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1747 wraps raw ML references, explicitly indicating their non-thread-safe
  1748 behaviour.  The Isar toplevel keeps this structure open, to
  1749 accommodate Proof General as well as quick and dirty interactive
  1750 experiments with references.
  1751 
  1752 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1753 parallel tactical reasoning.
  1754 
  1755 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1756 are similar to SUBPROOF, but are slightly more flexible: only the
  1757 specified parts of the subgoal are imported into the context, and the
  1758 body tactic may introduce new subgoals and schematic variables.
  1759 
  1760 * Old tactical METAHYPS, which does not observe the proof context, has
  1761 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1762 or Subgoal.FOCUS etc.
  1763 
  1764 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  1765 functors have their own ML name space there is no point to mark them
  1766 separately.)  Minor INCOMPATIBILITY.
  1767 
  1768 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  1769 
  1770 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  1771 INCOMPATIBILITY.
  1772 
  1773 * Operations of structure Skip_Proof no longer require quick_and_dirty
  1774 mode, which avoids critical setmp.
  1775 
  1776 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  1777 combinators for "args".  INCOMPATIBILITY, need to use simplified
  1778 Attrib/Method.setup introduced in Isabelle2009.
  1779 
  1780 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  1781 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  1782 last resort.  INCOMPATIBILITY.
  1783 
  1784 * Display.pretty_thm now requires a proper context (cf. former
  1785 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  1786 or even Display.pretty_thm_without_context as last resort.
  1787 INCOMPATIBILITY.
  1788 
  1789 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  1790 Syntax.pretty_typ/term directly, preferably with proper context
  1791 instead of global theory.
  1792 
  1793 
  1794 *** System ***
  1795 
  1796 * Further fine tuning of parallel proof checking, scales up to 8 cores
  1797 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  1798 usedir option -q.
  1799 
  1800 * Support for additional "Isabelle components" via etc/components, see
  1801 also the system manual.
  1802 
  1803 * The isabelle makeall tool now operates on all components with
  1804 IsaMakefile, not just hardwired "logics".
  1805 
  1806 * Removed "compress" option from isabelle-process and isabelle usedir;
  1807 this is always enabled.
  1808 
  1809 * Discontinued support for Poly/ML 4.x versions.
  1810 
  1811 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  1812 on a given logic image.  This requires the lighttpd webserver and is
  1813 currently supported on Linux only.
  1814 
  1815 
  1816 
  1817 New in Isabelle2009 (April 2009)
  1818 --------------------------------
  1819 
  1820 *** General ***
  1821 
  1822 * Simplified main Isabelle executables, with less surprises on
  1823 case-insensitive file-systems (such as Mac OS).
  1824 
  1825   - The main Isabelle tool wrapper is now called "isabelle" instead of
  1826     "isatool."
  1827 
  1828   - The former "isabelle" alias for "isabelle-process" has been
  1829     removed (should rarely occur to regular users).
  1830 
  1831   - The former "isabelle-interface" and its alias "Isabelle" have been
  1832     removed (interfaces are now regular Isabelle tools).
  1833 
  1834 Within scripts and make files, the Isabelle environment variables
  1835 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  1836 respectively.  (The latter are still available as legacy feature.)
  1837 
  1838 The old isabelle-interface wrapper could react in confusing ways if
  1839 the interface was uninstalled or changed otherwise.  Individual
  1840 interface tool configuration is now more explicit, see also the
  1841 Isabelle system manual.  In particular, Proof General is now available
  1842 via "isabelle emacs".
  1843 
  1844 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  1845 purge installed copies of Isabelle executables and re-run "isabelle
  1846 install -p ...", or use symlinks.
  1847 
  1848 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  1849 old ~/isabelle, which was slightly non-standard and apt to cause
  1850 surprises on case-insensitive file-systems (such as Mac OS).
  1851 
  1852 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  1853 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  1854 care is required when using older releases of Isabelle.  Note that
  1855 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  1856 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  1857 
  1858 * Proofs of fully specified statements are run in parallel on
  1859 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  1860 a regular 4-core machine, if the initial heap space is made reasonably
  1861 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  1862 
  1863 * The main reference manuals ("isar-ref", "implementation", and
  1864 "system") have been updated and extended.  Formally checked references
  1865 as hyperlinks are now available uniformly.
  1866 
  1867 
  1868 *** Pure ***
  1869 
  1870 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  1871 respects.  The most important changes are listed below.  See the
  1872 Tutorial on Locales ("locales" manual) for details.
  1873 
  1874 - In locale expressions, instantiation replaces renaming.  Parameters
  1875 must be declared in a for clause.  To aid compatibility with previous
  1876 parameter inheritance, in locale declarations, parameters that are not
  1877 'touched' (instantiation position "_" or omitted) are implicitly added
  1878 with their syntax at the beginning of the for clause.
  1879 
  1880 - Syntax from abbreviations and definitions in locales is available in
  1881 locale expressions and context elements.  The latter is particularly
  1882 useful in locale declarations.
  1883 
  1884 - More flexible mechanisms to qualify names generated by locale
  1885 expressions.  Qualifiers (prefixes) may be specified in locale
  1886 expressions, and can be marked as mandatory (syntax: "name!:") or
  1887 optional (syntax "name?:").  The default depends for plain "name:"
  1888 depends on the situation where a locale expression is used: in
  1889 commands 'locale' and 'sublocale' prefixes are optional, in
  1890 'interpretation' and 'interpret' prefixes are mandatory.  The old
  1891 implicit qualifiers derived from the parameter names of a locale are
  1892 no longer generated.
  1893 
  1894 - Command "sublocale l < e" replaces "interpretation l < e".  The
  1895 instantiation clause in "interpretation" and "interpret" (square
  1896 brackets) is no longer available.  Use locale expressions.
  1897 
  1898 - When converting proof scripts, mandatory qualifiers in
  1899 'interpretation' and 'interpret' should be retained by default, even
  1900 if this is an INCOMPATIBILITY compared to former behavior.  In the
  1901 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  1902 in locale expressions range over a single locale instance only.
  1903 
  1904 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  1905 In existing theorem specifications replace the includes element by the
  1906 respective context elements of the included locale, omitting those
  1907 that are already present in the theorem specification.  Multiple
  1908 assume elements of a locale should be replaced by a single one
  1909 involving the locale predicate.  In the proof body, declarations (most
  1910 notably theorems) may be regained by interpreting the respective
  1911 locales in the proof context as required (command "interpret").
  1912 
  1913 If using "includes" in replacement of a target solely because the
  1914 parameter types in the theorem are not as general as in the target,
  1915 consider declaring a new locale with additional type constraints on
  1916 the parameters (context element "constrains").
  1917 
  1918 - Discontinued "locale (open)".  INCOMPATIBILITY.
  1919 
  1920 - Locale interpretation commands no longer attempt to simplify goal.
  1921 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  1922 methods intro_locales and unfold_locales to clarify.
  1923 
  1924 - Locale interpretation commands no longer accept interpretation
  1925 attributes.  INCOMPATIBILITY.
  1926 
  1927 * Class declaration: so-called "base sort" must not be given in import
  1928 list any longer, but is inferred from the specification.  Particularly
  1929 in HOL, write
  1930 
  1931     class foo = ...
  1932 
  1933 instead of
  1934 
  1935     class foo = type + ...
  1936 
  1937 * Class target: global versions of theorems stemming do not carry a
  1938 parameter prefix any longer.  INCOMPATIBILITY.
  1939 
  1940 * Class 'instance' command no longer accepts attached definitions.
  1941 INCOMPATIBILITY, use proper 'instantiation' target instead.
  1942 
  1943 * Recovered hiding of consts, which was accidentally broken in
  1944 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  1945 makes c inaccessible; consider using ``hide (open) const c'' instead.
  1946 
  1947 * Slightly more coherent Pure syntax, with updated documentation in
  1948 isar-ref manual.  Removed locales meta_term_syntax and
  1949 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  1950 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  1951 directly in regular applications.
  1952 
  1953 * There is a new syntactic category "float_const" for signed decimal
  1954 fractions (e.g. 123.45 or -123.45).
  1955 
  1956 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  1957 interface with 'setup' command instead.
  1958 
  1959 * Command 'local_setup' is similar to 'setup', but operates on a local
  1960 theory context.
  1961 
  1962 * The 'axiomatization' command now only works within a global theory
  1963 context.  INCOMPATIBILITY.
  1964 
  1965 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  1966 hypotheses.  Sorts required in the course of reasoning need to be
  1967 covered by the constraints in the initial statement, completed by the
  1968 type instance information of the background theory.  Non-trivial sort
  1969 hypotheses, which rarely occur in practice, may be specified via
  1970 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  1971 
  1972   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  1973 
  1974 The result contains an implicit sort hypotheses as before --
  1975 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  1976 normalization.
  1977 
  1978 * Generalized Isar history, with support for linear undo, direct state
  1979 addressing etc.
  1980 
  1981 * Changed defaults for unify configuration options:
  1982 
  1983   unify_trace_bound = 50 (formerly 25)
  1984   unify_search_bound = 60 (formerly 30)
  1985 
  1986 * Different bookkeeping for code equations (INCOMPATIBILITY):
  1987 
  1988   a) On theory merge, the last set of code equations for a particular
  1989      constant is taken (in accordance with the policy applied by other
  1990      parts of the code generator framework).
  1991 
  1992   b) Code equations stemming from explicit declarations (e.g. code
  1993      attribute) gain priority over default code equations stemming
  1994      from definition, primrec, fun etc.
  1995 
  1996 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  1997 
  1998 * Unified theorem tables for both code generators.  Thus [code
  1999 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  2000 
  2001 * Command 'find_consts' searches for constants based on type and name
  2002 patterns, e.g.
  2003 
  2004     find_consts "_ => bool"
  2005 
  2006 By default, matching is against subtypes, but it may be restricted to
  2007 the whole type.  Searching by name is possible.  Multiple queries are
  2008 conjunctive and queries may be negated by prefixing them with a
  2009 hyphen:
  2010 
  2011     find_consts strict: "_ => bool" name: "Int" -"int => int"
  2012 
  2013 * New 'find_theorems' criterion "solves" matches theorems that
  2014 directly solve the current goal (modulo higher-order unification).
  2015 
  2016 * Auto solve feature for main theorem statements: whenever a new goal
  2017 is stated, "find_theorems solves" is called; any theorems that could
  2018 solve the lemma directly are listed as part of the goal state.
  2019 Cf. associated options in Proof General Isabelle settings menu,
  2020 enabled by default, with reasonable timeout for pathological cases of
  2021 higher-order unification.
  2022 
  2023 
  2024 *** Document preparation ***
  2025 
  2026 * Antiquotation @{lemma} now imitates a regular terminal proof,
  2027 demanding keyword 'by' and supporting the full method expression
  2028 syntax just like the Isar command 'by'.
  2029 
  2030 
  2031 *** HOL ***
  2032 
  2033 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  2034 points Main and Complex_Main remain as before.
  2035 
  2036 * Logic image HOL-Plain provides a minimal HOL with the most important
  2037 tools available (inductive, datatype, primrec, ...).  This facilitates
  2038 experimentation and tool development.  Note that user applications
  2039 (and library theories) should never refer to anything below theory
  2040 Main, as before.
  2041 
  2042 * Logic image HOL-Main stops at theory Main, and thus facilitates
  2043 experimentation due to shorter build times.
  2044 
  2045 * Logic image HOL-NSA contains theories of nonstandard analysis which
  2046 were previously part of former HOL-Complex.  Entry point Hyperreal
  2047 remains valid, but theories formerly using Complex_Main should now use
  2048 new entry point Hypercomplex.
  2049 
  2050 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  2051 Posix processes.  Avoids potentially expensive forking of the ML
  2052 process.  New thread-based implementation also works on non-Unix
  2053 platforms (Cygwin).  Provers are no longer hardwired, but defined
  2054 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  2055 commands are covered in the isar-ref manual.
  2056 
  2057 * Wrapper scripts for remote SystemOnTPTP service allows to use
  2058 sledgehammer without local ATP installation (Vampire etc.). Other
  2059 provers may be included via suitable ML wrappers, see also
  2060 src/HOL/ATP_Linkup.thy.
  2061 
  2062 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  2063 menu.
  2064 
  2065 * The metis method no longer fails because the theorem is too trivial
  2066 (contains the empty clause).
  2067 
  2068 * The metis method now fails in the usual manner, rather than raising
  2069 an exception, if it determines that it cannot prove the theorem.
  2070 
  2071 * Method "coherent" implements a prover for coherent logic (see also
  2072 src/Tools/coherent.ML).
  2073 
  2074 * Constants "undefined" and "default" replace "arbitrary".  Usually
  2075 "undefined" is the right choice to replace "arbitrary", though
  2076 logically there is no difference.  INCOMPATIBILITY.
  2077 
  2078 * Command "value" now integrates different evaluation mechanisms.  The
  2079 result of the first successful evaluation mechanism is printed.  In
  2080 square brackets a particular named evaluation mechanisms may be
  2081 specified (currently, [SML], [code] or [nbe]).  See further
  2082 src/HOL/ex/Eval_Examples.thy.
  2083 
  2084 * Normalization by evaluation now allows non-leftlinear equations.
  2085 Declare with attribute [code nbe].
  2086 
  2087 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  2088 as the structured Isar versions "cases" and "induct", cf. the
  2089 corresponding "cases" and "induct" attributes.  Mutual induction rules
  2090 are now presented as a list of individual projections
  2091 (e.g. foo_bar.inducts for types foo and bar); the old format with
  2092 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  2093 rare situations a different rule is selected --- notably nested tuple
  2094 elimination instead of former prod.exhaust: use explicit (case_tac t
  2095 rule: prod.exhaust) here.
  2096 
  2097 * Attributes "cases", "induct", "coinduct" support "del" option.
  2098 
  2099 * Removed fact "case_split_thm", which duplicates "case_split".
  2100 
  2101 * The option datatype has been moved to a new theory Option.  Renamed
  2102 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  2103 
  2104 * New predicate "strict_mono" classifies strict functions on partial
  2105 orders.  With strict functions on linear orders, reasoning about
  2106 (in)equalities is facilitated by theorems "strict_mono_eq",
  2107 "strict_mono_less_eq" and "strict_mono_less".
  2108 
  2109 * Some set operations are now proper qualified constants with
  2110 authentic syntax.  INCOMPATIBILITY:
  2111 
  2112     op Int ~>   Set.Int
  2113     op Un ~>    Set.Un
  2114     INTER ~>    Set.INTER
  2115     UNION ~>    Set.UNION
  2116     Inter ~>    Set.Inter
  2117     Union ~>    Set.Union
  2118     {} ~>       Set.empty
  2119     UNIV ~>     Set.UNIV
  2120 
  2121 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  2122 theory Set.
  2123 
  2124 * Auxiliary class "itself" has disappeared -- classes without any
  2125 parameter are treated as expected by the 'class' command.
  2126 
  2127 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  2128 
  2129 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  2130 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  2131 
  2132 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  2133 method "approximation".  It proves formulas on real values by using
  2134 interval arithmetic.  In the formulas are also the transcendental
  2135 functions sin, cos, tan, atan, ln, exp and the constant pi are
  2136 allowed. For examples see
  2137 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  2138 
  2139 * Theory "Reflection" now resides in HOL/Library.
  2140 
  2141 * Entry point to Word library now simply named "Word".
  2142 INCOMPATIBILITY.
  2143 
  2144 * Made source layout more coherent with logical distribution
  2145 structure:
  2146 
  2147     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  2148     src/HOL/Library/Code_Message.thy ~> src/HOL/
  2149     src/HOL/Library/GCD.thy ~> src/HOL/
  2150     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  2151     src/HOL/Library/Parity.thy ~> src/HOL/
  2152     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  2153     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  2154     src/HOL/Real/Lubs.thy ~> src/HOL/
  2155     src/HOL/Real/PReal.thy ~> src/HOL/
  2156     src/HOL/Real/Rational.thy ~> src/HOL/
  2157     src/HOL/Real/RComplete.thy ~> src/HOL/
  2158     src/HOL/Real/RealDef.thy ~> src/HOL/
  2159     src/HOL/Real/RealPow.thy ~> src/HOL/
  2160     src/HOL/Real/Real.thy ~> src/HOL/
  2161     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  2162     src/HOL/Complex/Complex.thy ~> src/HOL/
  2163     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  2164     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  2165     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  2166     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  2167     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  2168     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  2169     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  2170     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  2171     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  2172     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  2173     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  2174     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  2175     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  2176     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  2177     src/HOL/Real/Float ~> src/HOL/Library/
  2178     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  2179     src/HOL/Real/RealVector.thy ~> src/HOL/
  2180 
  2181     src/HOL/arith_data.ML ~> src/HOL/Tools
  2182     src/HOL/hologic.ML ~> src/HOL/Tools
  2183     src/HOL/simpdata.ML ~> src/HOL/Tools
  2184     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  2185     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  2186     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  2187     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  2188     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  2189     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  2190     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  2191 
  2192     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  2193     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  2194     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  2195     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  2196     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  2197     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  2198 
  2199 * If methods "eval" and "evaluation" encounter a structured proof
  2200 state with !!/==>, only the conclusion is evaluated to True (if
  2201 possible), avoiding strange error messages.
  2202 
  2203 * Method "sizechange" automates termination proofs using (a
  2204 modification of) the size-change principle.  Requires SAT solver.  See
  2205 src/HOL/ex/Termination.thy for examples.
  2206 
  2207 * Simplifier: simproc for let expressions now unfolds if bound
  2208 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  2209 
  2210 * Method "arith": Linear arithmetic now ignores all inequalities when
  2211 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  2212 
  2213 * New attribute "arith" for facts that should always be used
  2214 automatically by arithmetic. It is intended to be used locally in
  2215 proofs, e.g.
  2216 
  2217   assumes [arith]: "x > 0"
  2218 
  2219 Global usage is discouraged because of possible performance impact.
  2220 
  2221 * New classes "top" and "bot" with corresponding operations "top" and
  2222 "bot" in theory Orderings; instantiation of class "complete_lattice"
  2223 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  2224 
  2225 * Changed definition lemma "less_fun_def" in order to provide an
  2226 instance for preorders on functions; use lemma "less_le" instead.
  2227 INCOMPATIBILITY.
  2228 
  2229 * Theory Orderings: class "wellorder" moved here, with explicit
  2230 induction rule "less_induct" as assumption.  For instantiation of
  2231 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  2232 INCOMPATIBILITY.
  2233 
  2234 * Theory Orderings: added class "preorder" as superclass of "order".
  2235 INCOMPATIBILITY: Instantiation proofs for order, linorder
  2236 etc. slightly changed.  Some theorems named order_class.* now named
  2237 preorder_class.*.
  2238 
  2239 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  2240 "diag" to "Id_on".
  2241 
  2242 * Theory Finite_Set: added a new fold combinator of type
  2243 
  2244   ('a => 'b => 'b) => 'b => 'a set => 'b
  2245 
  2246 Occasionally this is more convenient than the old fold combinator
  2247 which is now defined in terms of the new one and renamed to
  2248 fold_image.
  2249 
  2250 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  2251 and "ring_simps" have been replaced by "algebra_simps" (which can be
  2252 extended with further lemmas!).  At the moment both still exist but
  2253 the former will disappear at some point.
  2254 
  2255 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  2256 class recpower.  Type-specific simp rules for various recpower types
  2257 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  2258 
  2259 rat_power_0    -> power_0
  2260 rat_power_Suc  -> power_Suc
  2261 realpow_0      -> power_0
  2262 realpow_Suc    -> power_Suc
  2263 complexpow_0   -> power_0
  2264 complexpow_Suc -> power_Suc
  2265 power_poly_0   -> power_0
  2266 power_poly_Suc -> power_Suc
  2267 
  2268 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  2269 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  2270 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  2271 of lemmas from Divides has been generalized from nat to class
  2272 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  2273 renames resulting from duplicate elimination:
  2274 
  2275     dvd_def_mod ~>          dvd_eq_mod_eq_0
  2276     zero_dvd_iff ~>         dvd_0_left_iff
  2277     dvd_0 ~>                dvd_0_right
  2278     DIVISION_BY_ZERO_DIV ~> div_by_0
  2279     DIVISION_BY_ZERO_MOD ~> mod_by_0
  2280     mult_div ~>             div_mult_self2_is_id
  2281     mult_mod ~>             mod_mult_self2_is_0
  2282 
  2283 * Theory IntDiv: removed many lemmas that are instances of class-based
  2284 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  2285 rename old lemmas as follows:
  2286 
  2287 dvd_diff               -> nat_dvd_diff
  2288 dvd_zminus_iff         -> dvd_minus_iff
  2289 mod_add1_eq            -> mod_add_eq
  2290 mod_mult1_eq           -> mod_mult_right_eq
  2291 mod_mult1_eq'          -> mod_mult_left_eq
  2292 mod_mult_distrib_mod   -> mod_mult_eq
  2293 nat_mod_add_left_eq    -> mod_add_left_eq
  2294 nat_mod_add_right_eq   -> mod_add_right_eq
  2295 nat_mod_div_trivial    -> mod_div_trivial
  2296 nat_mod_mod_trivial    -> mod_mod_trivial
  2297 zdiv_zadd_self1        -> div_add_self1
  2298 zdiv_zadd_self2        -> div_add_self2
  2299 zdiv_zmult_self1       -> div_mult_self2_is_id
  2300 zdiv_zmult_self2       -> div_mult_self1_is_id
  2301 zdvd_triv_left         -> dvd_triv_left
  2302 zdvd_triv_right        -> dvd_triv_right
  2303 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  2304 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  2305 zmod_zadd_left_eq      -> mod_add_left_eq
  2306 zmod_zadd_right_eq     -> mod_add_right_eq
  2307 zmod_zadd_self1        -> mod_add_self1
  2308 zmod_zadd_self2        -> mod_add_self2
  2309 zmod_zadd1_eq          -> mod_add_eq
  2310 zmod_zdiff1_eq         -> mod_diff_eq
  2311 zmod_zdvd_zmod         -> mod_mod_cancel
  2312 zmod_zmod_cancel       -> mod_mod_cancel
  2313 zmod_zmult_self1       -> mod_mult_self2_is_0
  2314 zmod_zmult_self2       -> mod_mult_self1_is_0
  2315 zmod_1                 -> mod_by_1
  2316 zdiv_1                 -> div_by_1
  2317 zdvd_abs1              -> abs_dvd_iff
  2318 zdvd_abs2              -> dvd_abs_iff
  2319 zdvd_refl              -> dvd_refl
  2320 zdvd_trans             -> dvd_trans
  2321 zdvd_zadd              -> dvd_add
  2322 zdvd_zdiff             -> dvd_diff
  2323 zdvd_zminus_iff        -> dvd_minus_iff
  2324 zdvd_zminus2_iff       -> minus_dvd_iff
  2325 zdvd_zmultD            -> dvd_mult_right
  2326 zdvd_zmultD2           -> dvd_mult_left
  2327 zdvd_zmult_mono        -> mult_dvd_mono
  2328 zdvd_0_right           -> dvd_0_right
  2329 zdvd_0_left            -> dvd_0_left_iff
  2330 zdvd_1_left            -> one_dvd
  2331 zminus_dvd_iff         -> minus_dvd_iff
  2332 
  2333 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  2334 
  2335 * The real numbers offer decimal input syntax: 12.34 is translated
  2336 into 1234/10^2. This translation is not reversed upon output.
  2337 
  2338 * Theory Library/Polynomial defines an abstract type 'a poly of
  2339 univariate polynomials with coefficients of type 'a.  In addition to
  2340 the standard ring operations, it also supports div and mod.  Code
  2341 generation is also supported, using list-style constructors.
  2342 
  2343 * Theory Library/Inner_Product defines a class of real_inner for real
  2344 inner product spaces, with an overloaded operation inner :: 'a => 'a
  2345 => real.  Class real_inner is a subclass of real_normed_vector from
  2346 theory RealVector.
  2347 
  2348 * Theory Library/Product_Vector provides instances for the product
  2349 type 'a * 'b of several classes from RealVector and Inner_Product.
  2350 Definitions of addition, subtraction, scalar multiplication, norms,
  2351 and inner products are included.
  2352 
  2353 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  2354 addition to the field operations, numerals and case syntax are also
  2355 supported.
  2356 
  2357 * Theory Library/Diagonalize provides constructive version of Cantor's
  2358 first diagonalization argument.
  2359 
  2360 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  2361 zlcm (for int); carried together from various gcd/lcm developements in
  2362 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  2363 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  2364 may recover tupled syntax as follows:
  2365 
  2366     hide (open) const gcd
  2367     abbreviation gcd where
  2368       "gcd == (%(a, b). GCD.gcd a b)"
  2369     notation (output)
  2370       GCD.gcd ("gcd '(_, _')")
  2371 
  2372 The same works for lcm, zgcd, zlcm.
  2373 
  2374 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  2375 instantiations for algebraic structures.  Removed some duplicate
  2376 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  2377 
  2378 * ML antiquotation @{code} takes a constant as argument and generates
  2379 corresponding code in background and inserts name of the corresponding
  2380 resulting ML value/function/datatype constructor binding in place.
  2381 All occurrences of @{code} with a single ML block are generated
  2382 simultaneously.  Provides a generic and safe interface for
  2383 instrumentalizing code generation.  See
  2384 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  2385 In future you ought to refrain from ad-hoc compiling generated SML
  2386 code on the ML toplevel.  Note that (for technical reasons) @{code}
  2387 cannot refer to constants for which user-defined serializations are
  2388 set.  Refer to the corresponding ML counterpart directly in that
  2389 cases.
  2390 
  2391 * Command 'rep_datatype': instead of theorem names the command now
  2392 takes a list of terms denoting the constructors of the type to be
  2393 represented as datatype.  The characteristic theorems have to be
  2394 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  2395 have disappeared in favour of existing ones:
  2396 
  2397     unit_induct                 ~> unit.induct
  2398     prod_induct                 ~> prod.induct
  2399     sum_induct                  ~> sum.induct
  2400     Suc_Suc_eq                  ~> nat.inject
  2401     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  2402 
  2403 
  2404 *** HOL-Algebra ***
  2405 
  2406 * New locales for orders and lattices where the equivalence relation
  2407 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  2408 locales use a record structure with field eq for the equivalence.
  2409 
  2410 * New theory of factorial domains.
  2411 
  2412 * Units_l_inv and Units_r_inv are now simp rules by default.
  2413 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  2414 and/or r_inv will now also require deletion of these lemmas.
  2415 
  2416 * Renamed the following theorems, INCOMPATIBILITY:
  2417 
  2418 UpperD ~> Upper_memD
  2419 LowerD ~> Lower_memD
  2420 least_carrier ~> least_closed
  2421 greatest_carrier ~> greatest_closed
  2422 greatest_Lower_above ~> greatest_Lower_below
  2423 one_zero ~> carrier_one_zero
  2424 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  2425 
  2426 
  2427 *** HOL-Nominal ***
  2428 
  2429 * Nominal datatypes can now contain type-variables.
  2430 
  2431 * Commands 'nominal_inductive' and 'equivariance' work with local
  2432 theory targets.
  2433 
  2434 * Nominal primrec can now works with local theory targets and its
  2435 specification syntax now conforms to the general format as seen in
  2436 'inductive' etc.
  2437 
  2438 * Method "perm_simp" honours the standard simplifier attributes
  2439 (no_asm), (no_asm_use) etc.
  2440 
  2441 * The new predicate #* is defined like freshness, except that on the
  2442 left hand side can be a set or list of atoms.
  2443 
  2444 * Experimental command 'nominal_inductive2' derives strong induction
  2445 principles for inductive definitions.  In contrast to
  2446 'nominal_inductive', which can only deal with a fixed number of
  2447 binders, it can deal with arbitrary expressions standing for sets of
  2448 atoms to be avoided.  The only inductive definition we have at the
  2449 moment that needs this generalisation is the typing rule for Lets in
  2450 the algorithm W:
  2451 
  2452  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  2453  -----------------------------------------------------------------
  2454          Gamma |- Let x be t1 in t2 : T2
  2455 
  2456 In this rule one wants to avoid all the binders that are introduced by
  2457 "close Gamma T1".  We are looking for other examples where this
  2458 feature might be useful.  Please let us know.
  2459 
  2460 
  2461 *** HOLCF ***
  2462 
  2463 * Reimplemented the simplification procedure for proving continuity
  2464 subgoals.  The new simproc is extensible; users can declare additional
  2465 continuity introduction rules with the attribute [cont2cont].
  2466 
  2467 * The continuity simproc now uses a different introduction rule for
  2468 solving continuity subgoals on terms with lambda abstractions.  In
  2469 some rare cases the new simproc may fail to solve subgoals that the
  2470 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  2471 Potential INCOMPATIBILITY.
  2472 
  2473 * Command 'fixrec': specification syntax now conforms to the general
  2474 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  2475 examples.  INCOMPATIBILITY.
  2476 
  2477 
  2478 *** ZF ***
  2479 
  2480 * Proof of Zorn's Lemma for partial orders.
  2481 
  2482 
  2483 *** ML ***
  2484 
  2485 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  2486 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  2487 depends on multithreading, so timouts will not work before Poly/ML
  2488 5.2.1!
  2489 
  2490 * High-level support for concurrent ML programming, see
  2491 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  2492 particularly convenient to organize independent functional
  2493 computations.  The concept of "synchronized variables" provides a
  2494 higher-order interface for components with shared state, avoiding the
  2495 delicate details of mutexes and condition variables.  (Requires
  2496 Poly/ML 5.2.1 or later.)
  2497 
  2498 * ML bindings produced via Isar commands are stored within the Isar
  2499 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2500 become thread-safe and work with undo as expected (concerning
  2501 top-level bindings, not side-effects on global references).
  2502 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2503 compiler at runtime; really global bindings need to be given outside a
  2504 theory.  (Requires Poly/ML 5.2 or later.)
  2505 
  2506 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2507 context.  Top-level ML bindings are stored within the proof context in
  2508 a purely sequential fashion, disregarding the nested proof structure.
  2509 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2510 proof.  (Requires Poly/ML 5.2 or later.)
  2511 
  2512 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2513 and Method.setup, as well as Isar commands 'attribute_setup' and
  2514 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2515 existing code accordingly, or use plain 'setup' together with old
  2516 Method.add_method.
  2517 
  2518 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2519 to 'a -> thm, while results are always tagged with an authentic oracle
  2520 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2521 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2522 accordingly.  Note that extra performance may be gained by producing
  2523 the cterm carefully, avoiding slow Thm.cterm_of.
  2524 
  2525 * Simplified interface for defining document antiquotations via
  2526 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2527 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2528 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2529 examples.
  2530 
  2531 * More systematic treatment of long names, abstract name bindings, and
  2532 name space operations.  Basic operations on qualified names have been
  2533 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2534 Long_Name.append.  Old type bstring has been mostly replaced by
  2535 abstract type binding (see structure Binding), which supports precise
  2536 qualification by packages and local theory targets, as well as proper
  2537 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2538 bstring values into Binding.name, or better pass through abstract
  2539 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2540 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2541 
  2542 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2543 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2544 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2545 
  2546 * Disposed old type and term read functions (Sign.read_def_typ,
  2547 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2548 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2549 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2550 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2551 resort for legacy applications.
  2552 
  2553 * Disposed old declarations, tactics, tactic combinators that refer to
  2554 the simpset or claset of an implicit theory (such as Addsimps,
  2555 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2556 embedded ML text, or local_simpset_of with a proper context passed as
  2557 explicit runtime argument.
  2558 
  2559 * Rules and tactics that read instantiations (read_instantiate,
  2560 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2561 context, which is required for parsing and type-checking.  Moreover,
  2562 the variables are specified as plain indexnames, not string encodings
  2563 thereof.  INCOMPATIBILITY.
  2564 
  2565 * Generic Toplevel.add_hook interface allows to analyze the result of
  2566 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2567 for theorem dependency output of transactions resulting in a new
  2568 theory state.
  2569 
  2570 * ML antiquotations: block-structured compilation context indicated by
  2571 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2572 
  2573   @{binding name}                         - basic name binding
  2574   @{let ?pat = term}                      - term abbreviation (HO matching)
  2575   @{note name = fact}                     - fact abbreviation
  2576   @{thm fact}                             - singleton fact (with attributes)
  2577   @{thms fact}                            - general fact (with attributes)
  2578   @{lemma prop by method}                 - singleton goal
  2579   @{lemma prop by meth1 meth2}            - singleton goal
  2580   @{lemma prop1 ... propN by method}      - general goal
  2581   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2582   @{lemma (open) ...}                     - open derivation
  2583 
  2584 
  2585 *** System ***
  2586 
  2587 * The Isabelle "emacs" tool provides a specific interface to invoke
  2588 Proof General / Emacs, with more explicit failure if that is not
  2589 installed (the old isabelle-interface script silently falls back on
  2590 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2591 installation location of the Proof General distribution.
  2592 
  2593 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2594 the Isabelle process into a JVM/Scala application.  See
  2595 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2596 process wrapper has been discontinued.)
  2597 
  2598 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2599 
  2600 * Various status messages (with exact source position information) are
  2601 emitted, if proper markup print mode is enabled.  This allows
  2602 user-interface components to provide detailed feedback on internal
  2603 prover operations.
  2604 
  2605 
  2606 
  2607 New in Isabelle2008 (June 2008)
  2608 -------------------------------
  2609 
  2610 *** General ***
  2611 
  2612 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2613 and updated, with formally checked references as hyperlinks.
  2614 
  2615 * Theory loader: use_thy (and similar operations) no longer set the
  2616 implicit ML context, which was occasionally hard to predict and in
  2617 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2618 provides a proper context already.
  2619 
  2620 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2621 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2622 'use' within a theory file will do the job.
  2623 
  2624 * Name space merge now observes canonical order, i.e. the second space
  2625 is inserted into the first one, while existing entries in the first
  2626 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2627 swap theory imports.
  2628 
  2629 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2630 INCOMPATIBILITY in identifier syntax etc.
  2631 
  2632 * Outer syntax: string tokens no longer admit escaped white space,
  2633 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2634 white space without escapes.
  2635 
  2636 * Outer syntax: string tokens may contain arbitrary character codes
  2637 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2638 "foo_bar".
  2639 
  2640 
  2641 *** Pure ***
  2642 
  2643 * Context-dependent token translations.  Default setup reverts locally
  2644 fixed variables, and adds hilite markup for undeclared frees.
  2645 
  2646 * Unused theorems can be found using the new command 'unused_thms'.
  2647 There are three ways of invoking it:
  2648 
  2649 (1) unused_thms
  2650      Only finds unused theorems in the current theory.
  2651 
  2652 (2) unused_thms thy_1 ... thy_n -
  2653      Finds unused theorems in the current theory and all of its ancestors,
  2654      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2655 
  2656 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2657      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2658      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2659      their ancestors.
  2660 
  2661 In order to increase the readability of the list produced by
  2662 unused_thms, theorems that have been created by a particular instance
  2663 of a theory command such as 'inductive' or 'function' are considered
  2664 to belong to the same "group", meaning that if at least one theorem in
  2665 this group is used, the other theorems in the same group are no longer
  2666 reported as unused.  Moreover, if all theorems in the group are
  2667 unused, only one theorem in the group is displayed.
  2668 
  2669 Note that proof objects have to be switched on in order for
  2670 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2671 usually the case when using Proof General with the default settings).
  2672 
  2673 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2674 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2675 duplicate fact bindings, or even accidental fact duplications.  Note
  2676 that tools may maintain dynamically scoped facts systematically, using
  2677 PureThy.add_thms_dynamic.
  2678 
  2679 * Command 'hide' now allows to hide from "fact" name space as well.
  2680 
  2681 * Eliminated destructive theorem database, simpset, claset, and
  2682 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2683 update of theories within ML code.
  2684 
  2685 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2686 INCOMPATIBILITY, object-logics depending on former Pure require
  2687 additional setup PureThy.old_appl_syntax_setup; object-logics
  2688 depending on former CPure need to refer to Pure.
  2689 
  2690 * Commands 'use' and 'ML' are now purely functional, operating on
  2691 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2692 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2693 INCOMPATIBILITY.
  2694 
  2695 * Command 'setup': discontinued implicit version with ML reference.
  2696 
  2697 * Instantiation target allows for simultaneous specification of class
  2698 instance operations together with an instantiation proof.
  2699 Type-checking phase allows to refer to class operations uniformly.
  2700 See src/HOL/Complex/Complex.thy for an Isar example and
  2701 src/HOL/Library/Eval.thy for an ML example.
  2702 
  2703 * Indexing of literal facts: be more serious about including only
  2704 facts from the visible specification/proof context, but not the
  2705 background context (locale etc.).  Affects `prop` notation and method
  2706 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2707 situations.
  2708 
  2709 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2710 "(open)" option, which used to expose internal bound variables to the
  2711 proof text.
  2712 
  2713 * Isar statements: removed obsolete case "rule_context".
  2714 INCOMPATIBILITY, better use explicit fixes/assumes.
  2715 
  2716 * Locale proofs: default proof step now includes 'unfold_locales';
  2717 hence 'proof' without argument may be used to unfold locale
  2718 predicates.
  2719 
  2720 
  2721 *** Document preparation ***
  2722 
  2723 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2724 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2725 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2726 spot); renamed link color from "darkblue" to "linkcolor" (default
  2727 value unchanged, can be redefined via \definecolor); no longer sets
  2728 "a4paper" option (unnecessary or even intrusive).
  2729 
  2730 * Antiquotation @{lemma A method} proves proposition A by the given
  2731 method (either a method name or a method name plus (optional) method
  2732 arguments in parentheses) and prints A just like @{prop A}.
  2733 
  2734 
  2735 *** HOL ***
  2736 
  2737 * New primrec package.  Specification syntax conforms in style to
  2738 definition/function/....  No separate induction rule is provided.  The
  2739 "primrec" command distinguishes old-style and new-style specifications
  2740 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2741 When adjusting theories, beware: constants stemming from new-style
  2742 primrec specifications have authentic syntax.
  2743 
  2744 * Metis prover is now an order of magnitude faster, and also works
  2745 with multithreading.
  2746 
  2747 * Metis: the maximum number of clauses that can be produced from a
  2748 theorem is now given by the attribute max_clauses.  Theorems that
  2749 exceed this number are ignored, with a warning printed.
  2750 
  2751 * Sledgehammer no longer produces structured proofs by default. To
  2752 enable, declare [[sledgehammer_full = true]].  Attributes
  2753 reconstruction_modulus, reconstruction_sorts renamed
  2754 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2755 
  2756 * Method "induct_scheme" derives user-specified induction rules
  2757 from well-founded induction and completeness of patterns. This factors
  2758 out some operations that are done internally by the function package
  2759 and makes them available separately.  See
  2760 src/HOL/ex/Induction_Scheme.thy for examples.
  2761 
  2762 * More flexible generation of measure functions for termination
  2763 proofs: Measure functions can be declared by proving a rule of the
  2764 form "is_measure f" and giving it the [measure_function] attribute.
  2765 The "is_measure" predicate is logically meaningless (always true), and
  2766 just guides the heuristic.  To find suitable measure functions, the
  2767 termination prover sets up the goal "is_measure ?f" of the appropriate
  2768 type and generates all solutions by prolog-style backwards proof using
  2769 the declared rules.
  2770 
  2771 This setup also deals with rules like 
  2772 
  2773   "is_measure f ==> is_measure (list_size f)"
  2774 
  2775 which accommodates nested datatypes that recurse through lists.
  2776 Similar rules are predeclared for products and option types.
  2777 
  2778 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  2779 
  2780   INCOMPATIBILITIES:
  2781 
  2782   - Definitions of overloaded constants on sets have to be replaced by
  2783     definitions on => and bool.
  2784 
  2785   - Some definitions of overloaded operators on sets can now be proved
  2786     using the definitions of the operators on => and bool.  Therefore,
  2787     the following theorems have been renamed:
  2788 
  2789       subset_def   -> subset_eq
  2790       psubset_def  -> psubset_eq
  2791       set_diff_def -> set_diff_eq
  2792       Compl_def    -> Compl_eq
  2793       Sup_set_def  -> Sup_set_eq
  2794       Inf_set_def  -> Inf_set_eq
  2795       sup_set_def  -> sup_set_eq
  2796       inf_set_def  -> inf_set_eq
  2797 
  2798   - Due to the incompleteness of the HO unification algorithm, some
  2799     rules such as subst may require manual instantiation, if some of
  2800     the unknowns in the rule is a set.
  2801 
  2802   - Higher order unification and forward proofs:
  2803     The proof pattern
  2804 
  2805       have "P (S::'a set)" <...>
  2806       then have "EX S. P S" ..
  2807 
  2808     no longer works (due to the incompleteness of the HO unification
  2809     algorithm) and must be replaced by the pattern
  2810 
  2811       have "EX S. P S"
  2812       proof
  2813         show "P S" <...>
  2814       qed
  2815 
  2816   - Calculational reasoning with subst (or similar rules):
  2817     The proof pattern
  2818 
  2819       have "P (S::'a set)" <...>
  2820       also have "S = T" <...>
  2821       finally have "P T" .
  2822 
  2823     no longer works (for similar reasons as the previous example) and
  2824     must be replaced by something like
  2825 
  2826       have "P (S::'a set)" <...>
  2827       moreover have "S = T" <...>
  2828       ultimately have "P T" by simp
  2829 
  2830   - Tactics or packages written in ML code:
  2831     Code performing pattern matching on types via
  2832 
  2833       Type ("set", [T]) => ...
  2834 
  2835     must be rewritten. Moreover, functions like strip_type or
  2836     binder_types no longer return the right value when applied to a
  2837     type of the form
  2838 
  2839       T1 => ... => Tn => U => bool
  2840 
  2841     rather than
  2842 
  2843       T1 => ... => Tn => U set
  2844 
  2845 * Merged theories Wellfounded_Recursion, Accessible_Part and
  2846 Wellfounded_Relations to theory Wellfounded.
  2847 
  2848 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  2849 
  2850 * Class finite no longer treats UNIV as class parameter.  Use class
  2851 enum from theory Library/Enum instead to achieve a similar effect.
  2852 INCOMPATIBILITY.
  2853 
  2854 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  2855 and "Cons".  INCOMPATIBILITY.
  2856 
  2857 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  2858 Potential INCOMPATIBILITY.
  2859 
  2860 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  2861 injective_fst_snd removed, use split_eta and prod_eqI instead.
  2862 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  2863 
  2864 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  2865 the same name in theory Orderings:
  2866 
  2867   less_trans
  2868   less_linear
  2869   le_imp_less_or_eq
  2870   le_less_trans
  2871   less_le_trans
  2872   less_not_sym
  2873   less_asym
  2874 
  2875 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  2876 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  2877 and different variable names.
  2878 
  2879 * Library/Option_ord.thy: Canonical order on option type.
  2880 
  2881 * Library/RBT.thy: Red-black trees, an efficient implementation of
  2882 finite maps.
  2883 
  2884 * Library/Countable.thy: Type class for countable types.
  2885 
  2886 * Theory Int: The representation of numerals has changed.  The infix
  2887 operator BIT and the bit datatype with constructors B0 and B1 have
  2888 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  2889 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  2890 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  2891 accordingly.
  2892 
  2893 * Theory Nat: definition of <= and < on natural numbers no longer
  2894 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  2895 le_def and less_def have disappeared.  Consider lemmas not_less
  2896 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  2897 
  2898 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  2899 (whose purpose mainly is for various fold_set functionals) have been
  2900 abandoned in favor of the existing algebraic classes
  2901 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  2902 lower_semilattice (resp. upper_semilattice) and linorder.
  2903 INCOMPATIBILITY.
  2904 
  2905 * Theory Transitive_Closure: induct and cases rules now declare proper
  2906 case_names ("base" and "step").  INCOMPATIBILITY.
  2907 
  2908 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  2909 lattices.  The form set-specific version is available as
  2910 Inductive.lfp_ordinal_induct_set.
  2911 
  2912 * Renamed theorems "power.simps" to "power_int.simps".
  2913 INCOMPATIBILITY.
  2914 
  2915 * Class semiring_div provides basic abstract properties of semirings
  2916 with division and modulo operations.  Subsumes former class dvd_mod.
  2917 
  2918 * Merged theories IntDef, Numeral and IntArith into unified theory
  2919 Int.  INCOMPATIBILITY.
  2920 
  2921 * Theory Library/Code_Index: type "index" now represents natural
  2922 numbers rather than integers.  INCOMPATIBILITY.
  2923 
  2924 * New class "uminus" with operation "uminus" (split of from class
  2925 "minus" which now only has operation "minus", binary).
  2926 INCOMPATIBILITY.
  2927 
  2928 * Constants "card", "internal_split", "option_map" now with authentic
  2929 syntax.  INCOMPATIBILITY.
  2930 
  2931 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  2932 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  2933 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  2934 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  2935 Sup_set_def, le_def, less_def, option_map_def now with object
  2936 equality.  INCOMPATIBILITY.
  2937 
  2938 * Records. Removed K_record, and replaced it by pure lambda term
  2939 %x. c. The simplifier setup is now more robust against eta expansion.
  2940 INCOMPATIBILITY: in cases explicitly referring to K_record.
  2941 
  2942 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  2943 
  2944 * Library/ListVector: new theory of arithmetic vector operations.
  2945 
  2946 * Library/Order_Relation: new theory of various orderings as sets of
  2947 pairs.  Defines preorders, partial orders, linear orders and
  2948 well-orders on sets and on types.
  2949 
  2950 
  2951 *** ZF ***
  2952 
  2953 * Renamed some theories to allow to loading both ZF and HOL in the
  2954 same session:
  2955 
  2956   Datatype  -> Datatype_ZF
  2957   Inductive -> Inductive_ZF
  2958   Int       -> Int_ZF
  2959   IntDiv    -> IntDiv_ZF
  2960   Nat       -> Nat_ZF
  2961   List      -> List_ZF
  2962   Main      -> Main_ZF
  2963 
  2964 INCOMPATIBILITY: ZF theories that import individual theories below
  2965 Main might need to be adapted.  Regular theory Main is still
  2966 available, as trivial extension of Main_ZF.
  2967 
  2968 
  2969 *** ML ***
  2970 
  2971 * ML within Isar: antiquotation @{const name} or @{const
  2972 name(typargs)} produces statically-checked Const term.
  2973 
  2974 * Functor NamedThmsFun: data is available to the user as dynamic fact
  2975 (of the same name).  Removed obsolete print command.
  2976 
  2977 * Removed obsolete "use_legacy_bindings" function.
  2978 
  2979 * The ``print mode'' is now a thread-local value derived from a global
  2980 template (the former print_mode reference), thus access becomes
  2981 non-critical.  The global print_mode reference is for session
  2982 management only; user-code should use print_mode_value,
  2983 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  2984 
  2985 * Functions system/system_out provide a robust way to invoke external
  2986 shell commands, with propagation of interrupts (requires Poly/ML
  2987 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  2988 
  2989 
  2990 *** System ***
  2991 
  2992 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  2993 in accordance with Proof General 3.7, which prefers GNU emacs.
  2994 
  2995 * isatool tty runs Isabelle process with plain tty interaction;
  2996 optional line editor may be specified via ISABELLE_LINE_EDITOR
  2997 setting, the default settings attempt to locate "ledit" and "rlwrap".
  2998 
  2999 * isatool browser now works with Cygwin as well, using general
  3000 "javapath" function defined in Isabelle process environment.
  3001 
  3002 * YXML notation provides a simple and efficient alternative to
  3003 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  3004 isatool yxml as described in the Isabelle system manual.
  3005 
  3006 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  3007 provides general wrapper for managing an Isabelle process in a robust
  3008 fashion, with ``cooked'' output from stdin/stderr.
  3009 
  3010 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  3011 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  3012 
  3013 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  3014 way of changing the user's settings is via
  3015 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  3016 script.
  3017 
  3018 * Multithreading.max_threads := 0 refers to the number of actual CPU
  3019 cores of the underlying machine, which is a good starting point for
  3020 optimal performance tuning.  The corresponding usedir option -M allows
  3021 "max" as an alias for "0".  WARNING: does not work on certain versions
  3022 of Mac OS (with Poly/ML 5.1).
  3023 
  3024 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  3025 adverse effect of Isabelle flooding interactive front-ends (notably
  3026 ProofGeneral / XEmacs).
  3027 
  3028 
  3029 
  3030 New in Isabelle2007 (November 2007)
  3031 -----------------------------------
  3032 
  3033 *** General ***
  3034 
  3035 * More uniform information about legacy features, notably a
  3036 warning/error of "Legacy feature: ...", depending on the state of the
  3037 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  3038 legacy features will disappear eventually.
  3039 
  3040 * Theory syntax: the header format ``theory A = B + C:'' has been
  3041 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  3042 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  3043 
  3044 * Theory syntax: the old non-Isar theory file format has been
  3045 discontinued altogether.  Note that ML proof scripts may still be used
  3046 with Isar theories; migration is usually quite simple with the ML
  3047 function use_legacy_bindings.  INCOMPATIBILITY.
  3048 
  3049 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  3050 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  3051 quotes.
  3052 
  3053 * Theory loader: be more serious about observing the static theory
  3054 header specifications (including optional directories), but not the
  3055 accidental file locations of previously successful loads.  The strict
  3056 update policy of former update_thy is now already performed by
  3057 use_thy, so the former has been removed; use_thys updates several
  3058 theories simultaneously, just as 'imports' within a theory header
  3059 specification, but without merging the results.  Potential
  3060 INCOMPATIBILITY: may need to refine theory headers and commands
  3061 ROOT.ML which depend on load order.
  3062 
  3063 * Theory loader: optional support for content-based file
  3064 identification, instead of the traditional scheme of full physical
  3065 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  3066 (cf. the system manual).  The new scheme allows to work with
  3067 non-finished theories in persistent session images, such that source
  3068 files may be moved later on without requiring reloads.
  3069 
  3070 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3071 file (with the same base name as the theory) are considered a legacy
  3072 feature, which will disappear eventually. Even now, the theory loader
  3073 no longer maintains dependencies on such files.
  3074 
  3075 * Syntax: the scope for resolving ambiguities via type-inference is
  3076 now limited to individual terms, instead of whole simultaneous
  3077 specifications as before. This greatly reduces the complexity of the
  3078 syntax module and improves flexibility by separating parsing and
  3079 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  3080 'fixes' etc.) are required in rare situations.
  3081 
  3082 * Syntax: constants introduced by new-style packages ('definition',
  3083 'abbreviation' etc.) are passed through the syntax module in
  3084 ``authentic mode''. This means that associated mixfix annotations
  3085 really stick to such constants, independently of potential name space
  3086 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  3087 trees are represented slightly differently, may need to adapt syntax
  3088 translations accordingly. Use CONST marker in 'translations' and
  3089 @{const_syntax} antiquotation in 'parse_translation' etc.
  3090 
  3091 * Legacy goal package: reduced interface to the bare minimum required
  3092 to keep existing proof scripts running.  Most other user-level
  3093 functions are now part of the OldGoals structure, which is *not* open
  3094 by default (consider isatool expandshort before open OldGoals).
  3095 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  3096 these tend to cause confusion about the actual goal (!) context being
  3097 used here, which is not necessarily the same as the_context().
  3098 
  3099 * Command 'find_theorems': supports "*" wild-card in "name:"
  3100 criterion; "with_dups" option.  Certain ProofGeneral versions might
  3101 support a specific search form (see ProofGeneral/CHANGES).
  3102 
  3103 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  3104 by default, which means that "prems" (and also "fixed variables") are
  3105 suppressed from proof state output.  Note that the ProofGeneral
  3106 settings mechanism allows to change and save options persistently, but
  3107 older versions of Isabelle will fail to start up if a negative prems
  3108 limit is imposed.
  3109 
  3110 * Local theory targets may be specified by non-nested blocks of
  3111 ``context/locale/class ... begin'' followed by ``end''.  The body may
  3112 contain definitions, theorems etc., including any derived mechanism
  3113 that has been implemented on top of these primitives.  This concept
  3114 generalizes the existing ``theorem (in ...)'' towards more versatility
  3115 and scalability.
  3116 
  3117 * Proof General interface: proper undo of final 'end' command;
  3118 discontinued Isabelle/classic mode (ML proof scripts).
  3119 
  3120 
  3121 *** Document preparation ***
  3122 
  3123 * Added antiquotation @{theory name} which prints the given name,
  3124 after checking that it refers to a valid ancestor theory in the
  3125 current context.
  3126 
  3127 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  3128 check the given source text as ML type/structure, printing verbatim.
  3129 
  3130 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  3131 "c args == rhs" given in the current context.  (Any number of
  3132 arguments may be given on the LHS.)
  3133 
  3134 
  3135 *** Pure ***
  3136 
  3137 * The 'class' package offers a combination of axclass and locale to
  3138 achieve Haskell-like type classes in Isabelle.  Definitions and
  3139 theorems within a class context produce both relative results (with
  3140 implicit parameters according to the locale context), and polymorphic
  3141 constants with qualified polymorphism (according to the class
  3142 context).  Within the body context of a 'class' target, a separate
  3143 syntax layer ("user space type system") takes care of converting
  3144 between global polymorphic consts and internal locale representation.
  3145 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  3146 "isatool doc classes" provides a tutorial.
  3147 
  3148 * Generic code generator framework allows to generate executable
  3149 code for ML and Haskell (including Isabelle classes).  A short usage
  3150 sketch:
  3151 
  3152     internal compilation:
  3153         export_code <list of constants (term syntax)> in SML
  3154     writing SML code to a file:
  3155         export_code <list of constants (term syntax)> in SML <filename>
  3156     writing OCaml code to a file:
  3157         export_code <list of constants (term syntax)> in OCaml <filename>
  3158     writing Haskell code to a bunch of files:
  3159         export_code <list of constants (term syntax)> in Haskell <filename>
  3160 
  3161     evaluating closed propositions to True/False using code generation:
  3162         method ``eval''
  3163 
  3164 Reasonable default setup of framework in HOL.
  3165 
  3166 Theorem attributs for selecting and transforming function equations theorems:
  3167 
  3168     [code fun]:        select a theorem as function equation for a specific constant
  3169     [code fun del]:    deselect a theorem as function equation for a specific constant
  3170     [code inline]:     select an equation theorem for unfolding (inlining) in place
  3171     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  3172 
  3173 User-defined serializations (target in {SML, OCaml, Haskell}):
  3174 
  3175     code_const <and-list of constants (term syntax)>
  3176       {(target) <and-list of const target syntax>}+
  3177 
  3178     code_type <and-list of type constructors>
  3179       {(target) <and-list of type target syntax>}+
  3180 
  3181     code_instance <and-list of instances>
  3182       {(target)}+
  3183         where instance ::= <type constructor> :: <class>
  3184 
  3185     code_class <and_list of classes>
  3186       {(target) <and-list of class target syntax>}+
  3187         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  3188 
  3189 code_instance and code_class only are effective to target Haskell.
  3190 
  3191 For example usage see src/HOL/ex/Codegenerator.thy and
  3192 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  3193 generation from Isabelle/HOL theories is available via "isatool doc
  3194 codegen".
  3195 
  3196 * Code generator: consts in 'consts_code' Isar commands are now
  3197 referred to by usual term syntax (including optional type
  3198 annotations).
  3199 
  3200 * Command 'no_translations' removes translation rules from theory
  3201 syntax.
  3202 
  3203 * Overloaded definitions are now actually checked for acyclic
  3204 dependencies.  The overloading scheme is slightly more general than
  3205 that of Haskell98, although Isabelle does not demand an exact
  3206 correspondence to type class and instance declarations.
  3207 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  3208 exotic versions of overloading -- at the discretion of the user!
  3209 
  3210 Polymorphic constants are represented via type arguments, i.e. the
  3211 instantiation that matches an instance against the most general
  3212 declaration given in the signature.  For example, with the declaration
  3213 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  3214 as c(nat).  Overloading is essentially simultaneous structural
  3215 recursion over such type arguments.  Incomplete specification patterns
  3216 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  3217 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  3218 Command 'print_theory' outputs the normalized system of recursive
  3219 equations, see section "definitions".
  3220 
  3221 * Configuration options are maintained within the theory or proof
  3222 context (with name and type bool/int/string), providing a very simple
  3223 interface to a poor-man's version of general context data.  Tools may
  3224 declare options in ML (e.g. using Attrib.config_int) and then refer to
  3225 these values using Config.get etc.  Users may change options via an
  3226 associated attribute of the same name.  This form of context
  3227 declaration works particularly well with commands 'declare' or
  3228 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  3229 very easy to avoid global references, which would not observe Isar
  3230 toplevel undo/redo and fail to work with multithreading.
  3231 
  3232 Various global ML references of Pure and HOL have been turned into
  3233 configuration options:
  3234 
  3235   Unify.search_bound		unify_search_bound
  3236   Unify.trace_bound		unify_trace_bound
  3237   Unify.trace_simp		unify_trace_simp
  3238   Unify.trace_types		unify_trace_types
  3239   Simplifier.simp_depth_limit	simp_depth_limit
  3240   Blast.depth_limit		blast_depth_limit
  3241   DatatypeProp.dtK		datatype_distinctness_limit
  3242   fast_arith_neq_limit  	fast_arith_neq_limit
  3243   fast_arith_split_limit	fast_arith_split_limit
  3244 
  3245 * Named collections of theorems may be easily installed as context
  3246 data using the functor NamedThmsFun (see also
  3247 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  3248 attributes; there is also a toplevel print command.  This facility is
  3249 just a common case of general context data, which is the preferred way
  3250 for anything more complex than just a list of facts in canonical
  3251 order.
  3252 
  3253 * Isar: command 'declaration' augments a local theory by generic
  3254 declaration functions written in ML.  This enables arbitrary content
  3255 being added to the context, depending on a morphism that tells the
  3256 difference of the original declaration context wrt. the application
  3257 context encountered later on.
  3258 
  3259 * Isar: proper interfaces for simplification procedures.  Command
  3260 'simproc_setup' declares named simprocs (with match patterns, and body
  3261 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  3262 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  3263 
  3264 * Isar: an extra pair of brackets around attribute declarations
  3265 abbreviates a theorem reference involving an internal dummy fact,
  3266 which will be ignored later --- only the effect of the attribute on
  3267 the background context will persist.  This form of in-place
  3268 declarations is particularly useful with commands like 'declare' and
  3269 'using', for example ``have A using [[simproc a]] by simp''.
  3270 
  3271 * Isar: method "assumption" (and implicit closing of subproofs) now
  3272 takes simple non-atomic goal assumptions into account: after applying
  3273 an assumption as a rule the resulting subgoals are solved by atomic
  3274 assumption steps.  This is particularly useful to finish 'obtain'
  3275 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  3276 without referring to the original premise "!!x. P x ==> thesis" in the
  3277 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  3278 more permissive.
  3279 
  3280 * Isar: implicit use of prems from the Isar proof context is
  3281 considered a legacy feature.  Common applications like ``have A .''
  3282 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  3283 referencing facts explicitly here improves readability and
  3284 maintainability of proof texts.
  3285 
  3286 * Isar: improper proof element 'guess' is like 'obtain', but derives
  3287 the obtained context from the course of reasoning!  For example:
  3288 
  3289   assume "EX x y. A x & B y"   -- "any previous fact"
  3290   then guess x and y by clarify
  3291 
  3292 This technique is potentially adventurous, depending on the facts and
  3293 proof tools being involved here.
  3294 
  3295 * Isar: known facts from the proof context may be specified as literal
  3296 propositions, using ASCII back-quote syntax.  This works wherever
  3297 named facts used to be allowed so far, in proof commands, proof
  3298 methods, attributes etc.  Literal facts are retrieved from the context
  3299 according to unification of type and term parameters.  For example,
  3300 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  3301 theorems in the current context, then these are valid literal facts:
  3302 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  3303 
  3304 There is also a proof method "fact" which does the same composition
  3305 for explicit goal states, e.g. the following proof texts coincide with
  3306 certain special cases of literal facts:
  3307 
  3308   have "A" by fact                 ==  note `A`
  3309   have "A ==> B" by fact           ==  note `A ==> B`
  3310   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  3311   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  3312 
  3313 * Isar: ":" (colon) is no longer a symbolic identifier character in
  3314 outer syntax.  Thus symbolic identifiers may be used without
  3315 additional white space in declarations like this: ``assume *: A''.
  3316 
  3317 * Isar: 'print_facts' prints all local facts of the current context,
  3318 both named and unnamed ones.
  3319 
  3320 * Isar: 'def' now admits simultaneous definitions, e.g.:
  3321 
  3322   def x == "t" and y == "u"
  3323 
  3324 * Isar: added command 'unfolding', which is structurally similar to
  3325 'using', but affects both the goal state and facts by unfolding given
  3326 rewrite rules.  Thus many occurrences of the 'unfold' method or
  3327 'unfolded' attribute may be replaced by first-class proof text.
  3328 
  3329 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  3330 and command 'unfolding' now all support object-level equalities
  3331 (potentially conditional).  The underlying notion of rewrite rule is
  3332 analogous to the 'rule_format' attribute, but *not* that of the
  3333 Simplifier (which is usually more generous).
  3334 
  3335 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  3336 premises of a theorem by n. Useful in conjunction with drule.
  3337 
  3338 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  3339 method expression within a sandbox consisting of the first N
  3340 sub-goals, which need to exist.  For example, ``simp_all [3]''
  3341 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  3342 simplifies all new goals that emerge from applying rule foo to the
  3343 originally first one.
  3344 
  3345 * Isar: schematic goals are no longer restricted to higher-order
  3346 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  3347 expected.
  3348 
  3349 * Isar: the conclusion of a long theorem statement is now either
  3350 'shows' (a simultaneous conjunction, as before), or 'obtains'
  3351 (essentially a disjunction of cases with local parameters and
  3352 assumptions).  The latter allows to express general elimination rules
  3353 adequately; in this notation common elimination rules look like this:
  3354 
  3355   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  3356     assumes "EX x. P x"
  3357     obtains x where "P x"
  3358 
  3359   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  3360     assumes "A & B"
  3361     obtains A and B
  3362 
  3363   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  3364     assumes "A | B"
  3365     obtains
  3366       A
  3367     | B
  3368 
  3369 The subsequent classical rules even refer to the formal "thesis"
  3370 explicitly:
  3371 
  3372   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  3373     obtains "~ thesis"
  3374 
  3375   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  3376     obtains "thesis ==> something"
  3377 
  3378 The actual proof of an 'obtains' statement is analogous to that of the
  3379 Isar proof element 'obtain', only that there may be several cases.
  3380 Optional case names may be specified in parentheses; these will be
  3381 available both in the present proof and as annotations in the
  3382 resulting rule, for later use with the 'cases' method (cf. attribute
  3383 case_names).
  3384 
  3385 * Isar: the assumptions of a long theorem statement are available as
  3386 "assms" fact in the proof context.  This is more appropriate than the
  3387 (historical) "prems", which refers to all assumptions of the current
  3388 context, including those from the target locale, proof body etc.
  3389 
  3390 * Isar: 'print_statement' prints theorems from the current theory or
  3391 proof context in long statement form, according to the syntax of a
  3392 top-level lemma.
  3393 
  3394 * Isar: 'obtain' takes an optional case name for the local context
  3395 introduction rule (default "that").
  3396 
  3397 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  3398 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  3399 to occur.
  3400 
  3401 * Pure: syntax "CONST name" produces a fully internalized constant
  3402 according to the current context.  This is particularly useful for
  3403 syntax translations that should refer to internal constant
  3404 representations independently of name spaces.
  3405 
  3406 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  3407 instead of "FOO ". This allows multiple binder declarations to coexist
  3408 in the same context.  INCOMPATIBILITY.
  3409 
  3410 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  3411 primitive that also works in a locale context (both for constants and
  3412 fixed variables). Type declaration and internal syntactic representation
  3413 of given constants retrieved from the context. Likewise, the
  3414 'no_notation' command allows to remove given syntax annotations from the
  3415 current context.
  3416 
  3417 * Isar/locales: new derived specification elements 'axiomatization',
  3418 'definition', 'abbreviation', which support type-inference, admit
  3419 object-level specifications (equality, equivalence).  See also the
  3420 isar-ref manual.  Examples:
  3421 
  3422   axiomatization
  3423     eq  (infix "===" 50) where
  3424     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  3425 
  3426   definition "f x y = x + y + 1"
  3427   definition g where "g x = f x x"
  3428 
  3429   abbreviation
  3430     neq  (infix "=!=" 50) where
  3431     "x =!= y == ~ (x === y)"
  3432 
  3433 These specifications may be also used in a locale context.  Then the
  3434 constants being introduced depend on certain fixed parameters, and the
  3435 constant name is qualified by the locale base name.  An internal
  3436 abbreviation takes care for convenient input and output, making the
  3437 parameters implicit and using the original short name.  See also
  3438 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  3439 entities from a monomorphic theory.
  3440 
  3441 Presently, abbreviations are only available 'in' a target locale, but
  3442 not inherited by general import expressions.  Also note that
  3443 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  3444 'translations' in common applications.  The "no_abbrevs" print mode
  3445 prevents folding of abbreviations in term output.
  3446 
  3447 Concrete syntax is attached to specified constants in internal form,
  3448 independently of name spaces.  The parse tree representation is
  3449 slightly different -- use 'notation' instead of raw 'syntax', and
  3450 'translations' with explicit "CONST" markup to accommodate this.
  3451 
  3452 * Pure/Isar: unified syntax for new-style specification mechanisms
  3453 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  3454 full type inference and dummy patterns ("_").  For example:
  3455 
  3456   definition "K x _ = x"
  3457 
  3458   inductive conj for A B
  3459   where "A ==> B ==> conj A B"
  3460 
  3461 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  3462 the current context.  Print mode "no_abbrevs" prevents inversion of
  3463 abbreviations on output.
  3464 
  3465 * Isar/locales: improved parameter handling: use of locales "var" and
  3466 "struct" no longer necessary; - parameter renamings are no longer
  3467 required to be injective.  For example, this allows to define
  3468 endomorphisms as locale endom = homom mult mult h.
  3469 
  3470 * Isar/locales: changed the way locales with predicates are defined.
  3471 Instead of accumulating the specification, the imported expression is
  3472 now an interpretation.  INCOMPATIBILITY: different normal form of
  3473 locale expressions.  In particular, in interpretations of locales with
  3474 predicates, goals repesenting already interpreted fragments are not
  3475 removed automatically.  Use methods `intro_locales' and
  3476 `unfold_locales'; see below.
  3477 
  3478 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  3479 provide backward reasoning on locales predicates.  The methods are
  3480 aware of interpretations and discharge corresponding goals.
  3481 `intro_locales' is less aggressive then `unfold_locales' and does not
  3482 unfold predicates to assumptions.
  3483 
  3484 * Isar/locales: the order in which locale fragments are accumulated
  3485 has changed.  This enables to override declarations from fragments due
  3486 to interpretations -- for example, unwanted simp rules.
  3487 
  3488 * Isar/locales: interpretation in theories and proof contexts has been
  3489 extended.  One may now specify (and prove) equations, which are
  3490 unfolded in interpreted theorems.  This is useful for replacing
  3491 defined concepts (constants depending on locale parameters) by
  3492 concepts already existing in the target context.  Example:
  3493 
  3494   interpretation partial_order ["op <= :: [int, int] => bool"]
  3495     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3496 
  3497 Typically, the constant `partial_order.less' is created by a
  3498 definition specification element in the context of locale
  3499 partial_order.
  3500 
  3501 * Method "induct": improved internal context management to support
  3502 local fixes and defines on-the-fly. Thus explicit meta-level
  3503 connectives !!  and ==> are rarely required anymore in inductive goals
  3504 (using object-logic connectives for this purpose has been long
  3505 obsolete anyway). Common proof patterns are explained in
  3506 src/HOL/Induct/Common_Patterns.thy, see also
  3507 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3508 examples.
  3509 
  3510 * Method "induct": improved handling of simultaneous goals. Instead of
  3511 introducing object-level conjunction, the statement is now split into
  3512 several conclusions, while the corresponding symbolic cases are nested
  3513 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3514 see src/HOL/Induct/Common_Patterns.thy, for example.
  3515 
  3516 * Method "induct": mutual induction rules are now specified as a list
  3517 of rule sharing the same induction cases. HOL packages usually provide
  3518 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3519 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3520 mutual induction rules differently, i.e. like this:
  3521 
  3522   (induct rule: foo_bar.inducts)
  3523   (induct set: foo bar)
  3524   (induct pred: foo bar)
  3525   (induct type: foo bar)
  3526 
  3527 The ML function ProjectRule.projections turns old-style rules into the
  3528 new format.
  3529 
  3530 * Method "coinduct": dual of induction, see
  3531 src/HOL/Library/Coinductive_List.thy for various examples.
  3532 
  3533 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3534 considered a legacy feature.
  3535 
  3536 * Attribute "symmetric" produces result with standardized schematic
  3537 variables (index 0).  Potential INCOMPATIBILITY.
  3538 
  3539 * Simplifier: by default the simplifier trace only shows top level
  3540 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3541 default. Thus there is less danger of being flooded by the trace. The
  3542 trace indicates where parts have been suppressed.
  3543   
  3544 * Provers/classical: removed obsolete classical version of elim_format
  3545 attribute; classical elim/dest rules are now treated uniformly when
  3546 manipulating the claset.
  3547 
  3548 * Provers/classical: stricter checks to ensure that supplied intro,
  3549 dest and elim rules are well-formed; dest and elim rules must have at
  3550 least one premise.
  3551 
  3552 * Provers/classical: attributes dest/elim/intro take an optional
  3553 weight argument for the rule (just as the Pure versions).  Weights are
  3554 ignored by automated tools, but determine the search order of single
  3555 rule steps.
  3556 
  3557 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3558 where the body does not mention the bound variable.  Note that dummy
  3559 patterns implicitly depend on their context of bounds, which makes
  3560 "{_. _}" match any set comprehension as expected.  Potential
  3561 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3562 constant "_idtdummy" in the binding position.
  3563 
  3564 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3565 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3566 for example "A -> B" => "Pi A (%_. B)".
  3567 
  3568 * Pure: 'class_deps' command visualizes the subclass relation, using
  3569 the graph browser tool.
  3570 
  3571 * Pure: 'print_theory' now suppresses certain internal declarations by
  3572 default; use '!' option for full details.
  3573 
  3574 
  3575 *** HOL ***
  3576 
  3577 * Method "metis" proves goals by applying the Metis general-purpose
  3578 resolution prover (see also http://gilith.com/software/metis/).
  3579 Examples are in the directory MetisExamples.  WARNING: the
  3580 Isabelle/HOL-Metis integration does not yet work properly with
  3581 multi-threading.
  3582   
  3583 * Command 'sledgehammer' invokes external automatic theorem provers as
  3584 background processes.  It generates calls to the "metis" method if
  3585 successful. These can be pasted into the proof.  Users do not have to
  3586 wait for the automatic provers to return.  WARNING: does not really
  3587 work with multi-threading.
  3588 
  3589 * New "auto_quickcheck" feature tests outermost goal statements for
  3590 potential counter-examples.  Controlled by ML references
  3591 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3592 5000 milliseconds).  Fails silently if statements is outside of
  3593 executable fragment, or any other codgenerator problem occurs.
  3594 
  3595 * New constant "undefined" with axiom "undefined x = undefined".
  3596 
  3597 * Added class "HOL.eq", allowing for code generation with polymorphic
  3598 equality.
  3599 
  3600 * Some renaming of class constants due to canonical name prefixing in
  3601 the new 'class' package:
  3602 
  3603     HOL.abs ~> HOL.abs_class.abs
  3604     HOL.divide ~> HOL.divide_class.divide
  3605     0 ~> HOL.zero_class.zero
  3606     1 ~> HOL.one_class.one
  3607     op + ~> HOL.plus_class.plus
  3608     op - ~> HOL.minus_class.minus
  3609     uminus ~> HOL.minus_class.uminus
  3610     op * ~> HOL.times_class.times
  3611     op < ~> HOL.ord_class.less
  3612     op <= > HOL.ord_class.less_eq
  3613     Nat.power ~> Power.power_class.power
  3614     Nat.size ~> Nat.size_class.size
  3615     Numeral.number_of ~> Numeral.number_class.number_of
  3616     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3617     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3618     Orderings.min ~> Orderings.ord_class.min
  3619     Orderings.max ~> Orderings.ord_class.max
  3620     Divides.op div ~> Divides.div_class.div
  3621     Divides.op mod ~> Divides.div_class.mod
  3622     Divides.op dvd ~> Divides.div_class.dvd
  3623 
  3624 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3625 
  3626 a) User-defined constants using any of the names "plus", "minus",
  3627 "times", "less" or "less_eq". The standard syntax translations for
  3628 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3629 names.
  3630 
  3631 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3632 INCOMPATIBILITY: use more specific names.
  3633 
  3634 c) Permutative equations (e.g. "a + b = b + a")
  3635 Since the change of names also changes the order of terms, permutative
  3636 rewrite rules may get applied in a different order. Experience shows
  3637 that this is rarely the case (only two adaptions in the whole Isabelle
  3638 distribution).  INCOMPATIBILITY: rewrite proofs
  3639 
  3640 d) ML code directly refering to constant names
  3641 This in general only affects hand-written proof tactics, simprocs and
  3642 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3643 Consider using @{const_name} antiquotation.
  3644 
  3645 * New class "default" with associated constant "default".
  3646 
  3647 * Function "sgn" is now overloaded and available on int, real, complex
  3648 (and other numeric types), using class "sgn".  Two possible defs of
  3649 sgn are given as equational assumptions in the classes sgn_if and
  3650 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3651 INCOMPATIBILITY.
  3652 
  3653 * Locale "partial_order" now unified with class "order" (cf. theory
  3654 Orderings), added parameter "less".  INCOMPATIBILITY.
  3655 
  3656 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3657 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3658 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3659 
  3660 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3661 changed order of proof goals in instance proofs.
  3662 
  3663 * The transitivity reasoner for partial and linear orders is set up
  3664 for classes "order" and "linorder".  Instances of the reasoner are available
  3665 in all contexts importing or interpreting the corresponding locales.
  3666 Method "order" invokes the reasoner separately; the reasoner
  3667 is also integrated with the Simplifier as a solver.  Diagnostic
  3668 command 'print_orders' shows the available instances of the reasoner
  3669 in the current context.
  3670 
  3671 * Localized monotonicity predicate in theory "Orderings"; integrated
  3672 lemmas max_of_mono and min_of_mono with this predicate.
  3673 INCOMPATIBILITY.
  3674 
  3675 * Formulation of theorem "dense" changed slightly due to integration
  3676 with new class dense_linear_order.
  3677 
  3678 * Uniform lattice theory development in HOL.
  3679 
  3680     constants "meet" and "join" now named "inf" and "sup"
  3681     constant "Meet" now named "Inf"
  3682 
  3683     classes "meet_semilorder" and "join_semilorder" now named
  3684       "lower_semilattice" and "upper_semilattice"
  3685     class "lorder" now named "lattice"
  3686     class "comp_lat" now named "complete_lattice"
  3687 
  3688     Instantiation of lattice classes allows explicit definitions
  3689     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3690 
  3691   INCOMPATIBILITY.  Theorem renames:
  3692 
  3693     meet_left_le            ~> inf_le1
  3694     meet_right_le           ~> inf_le2
  3695     join_left_le            ~> sup_ge1
  3696     join_right_le           ~> sup_ge2
  3697     meet_join_le            ~> inf_sup_ord
  3698     le_meetI                ~> le_infI
  3699     join_leI                ~> le_supI
  3700     le_meet                 ~> le_inf_iff
  3701     le_join                 ~> ge_sup_conv
  3702     meet_idempotent         ~> inf_idem
  3703     join_idempotent         ~> sup_idem
  3704     meet_comm               ~> inf_commute
  3705     join_comm               ~> sup_commute
  3706     meet_leI1               ~> le_infI1
  3707     meet_leI2               ~> le_infI2
  3708     le_joinI1               ~> le_supI1
  3709     le_joinI2               ~> le_supI2
  3710     meet_assoc              ~> inf_assoc
  3711     join_assoc              ~> sup_assoc
  3712     meet_left_comm          ~> inf_left_commute
  3713     meet_left_idempotent    ~> inf_left_idem
  3714     join_left_comm          ~> sup_left_commute
  3715     join_left_idempotent    ~> sup_left_idem
  3716     meet_aci                ~> inf_aci
  3717     join_aci                ~> sup_aci
  3718     le_def_meet             ~> le_iff_inf
  3719     le_def_join             ~> le_iff_sup
  3720     join_absorp2            ~> sup_absorb2
  3721     join_absorp1            ~> sup_absorb1
  3722     meet_absorp1            ~> inf_absorb1
  3723     meet_absorp2            ~> inf_absorb2
  3724     meet_join_absorp        ~> inf_sup_absorb
  3725     join_meet_absorp        ~> sup_inf_absorb
  3726     distrib_join_le         ~> distrib_sup_le
  3727     distrib_meet_le         ~> distrib_inf_le
  3728 
  3729     add_meet_distrib_left   ~> add_inf_distrib_left
  3730     add_join_distrib_left   ~> add_sup_distrib_left
  3731     is_join_neg_meet        ~> is_join_neg_inf
  3732     is_meet_neg_join        ~> is_meet_neg_sup
  3733     add_meet_distrib_right  ~> add_inf_distrib_right
  3734     add_join_distrib_right  ~> add_sup_distrib_right
  3735     add_meet_join_distribs  ~> add_sup_inf_distribs
  3736     join_eq_neg_meet        ~> sup_eq_neg_inf
  3737     meet_eq_neg_join        ~> inf_eq_neg_sup
  3738     add_eq_meet_join        ~> add_eq_inf_sup
  3739     meet_0_imp_0            ~> inf_0_imp_0
  3740     join_0_imp_0            ~> sup_0_imp_0
  3741     meet_0_eq_0             ~> inf_0_eq_0
  3742     join_0_eq_0             ~> sup_0_eq_0
  3743     neg_meet_eq_join        ~> neg_inf_eq_sup
  3744     neg_join_eq_meet        ~> neg_sup_eq_inf
  3745     join_eq_if              ~> sup_eq_if
  3746 
  3747     mono_meet               ~> mono_inf
  3748     mono_join               ~> mono_sup
  3749     meet_bool_eq            ~> inf_bool_eq
  3750     join_bool_eq            ~> sup_bool_eq
  3751     meet_fun_eq             ~> inf_fun_eq
  3752     join_fun_eq             ~> sup_fun_eq
  3753     meet_set_eq             ~> inf_set_eq
  3754     join_set_eq             ~> sup_set_eq
  3755     meet1_iff               ~> inf1_iff
  3756     meet2_iff               ~> inf2_iff
  3757     meet1I                  ~> inf1I
  3758     meet2I                  ~> inf2I
  3759     meet1D1                 ~> inf1D1
  3760     meet2D1                 ~> inf2D1
  3761     meet1D2                 ~> inf1D2
  3762     meet2D2                 ~> inf2D2
  3763     meet1E                  ~> inf1E
  3764     meet2E                  ~> inf2E
  3765     join1_iff               ~> sup1_iff
  3766     join2_iff               ~> sup2_iff
  3767     join1I1                 ~> sup1I1
  3768     join2I1                 ~> sup2I1
  3769     join1I1                 ~> sup1I1
  3770     join2I2                 ~> sup1I2
  3771     join1CI                 ~> sup1CI
  3772     join2CI                 ~> sup2CI
  3773     join1E                  ~> sup1E
  3774     join2E                  ~> sup2E
  3775 
  3776     is_meet_Meet            ~> is_meet_Inf
  3777     Meet_bool_def           ~> Inf_bool_def
  3778     Meet_fun_def            ~> Inf_fun_def
  3779     Meet_greatest           ~> Inf_greatest
  3780     Meet_lower              ~> Inf_lower
  3781     Meet_set_def            ~> Inf_set_def
  3782 
  3783     Sup_def                 ~> Sup_Inf
  3784     Sup_bool_eq             ~> Sup_bool_def
  3785     Sup_fun_eq              ~> Sup_fun_def
  3786     Sup_set_eq              ~> Sup_set_def
  3787 
  3788     listsp_meetI            ~> listsp_infI
  3789     listsp_meet_eq          ~> listsp_inf_eq
  3790 
  3791     meet_min                ~> inf_min
  3792     join_max                ~> sup_max
  3793 
  3794 * Added syntactic class "size"; overloaded constant "size" now has
  3795 type "'a::size ==> bool"
  3796 
  3797 * Internal reorganisation of `size' of datatypes: size theorems
  3798 "foo.size" are no longer subsumed by "foo.simps" (but are still
  3799 simplification rules by default!); theorems "prod.size" now named
  3800 "*.size".
  3801 
  3802 * Class "div" now inherits from class "times" rather than "type".
  3803 INCOMPATIBILITY.
  3804 
  3805 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  3806 Linorder etc.  have disappeared; operations defined in terms of
  3807 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  3808 
  3809 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  3810 
  3811 * HOL-Word: New extensive library and type for generic, fixed size
  3812 machine words, with arithemtic, bit-wise, shifting and rotating
  3813 operations, reflection into int, nat, and bool lists, automation for
  3814 linear arithmetic (by automatic reflection into nat or int), including
  3815 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  3816 arithmetic type classes, supporting automatic simplification of
  3817 numerals on all operations.
  3818 
  3819 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  3820 
  3821 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  3822 
  3823 * Code generator library theories:
  3824   - Code_Integer represents HOL integers by big integer literals in target
  3825     languages.
  3826   - Code_Char represents HOL characters by character literals in target
  3827     languages.
  3828   - Code_Char_chr like Code_Char, but also offers treatment of character
  3829     codes; includes Code_Integer.
  3830   - Executable_Set allows to generate code for finite sets using lists.
  3831   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  3832     denominator).
  3833   - Executable_Real implements a subset of real numbers, namly those
  3834     representable by rational numbers.
  3835   - Efficient_Nat implements natural numbers by integers, which in general will
  3836     result in higher efficency; pattern matching with 0/Suc is eliminated;
  3837     includes Code_Integer.
  3838   - Code_Index provides an additional datatype index which is mapped to
  3839     target-language built-in integers.
  3840   - Code_Message provides an additional datatype message_string which is isomorphic to
  3841     strings; messages are mapped to target-language strings.
  3842 
  3843 * New package for inductive predicates
  3844 
  3845   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  3846 
  3847     inductive
  3848       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3849       for z_1 :: U_1 and ... and z_n :: U_m
  3850     where
  3851       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3852     | ...
  3853 
  3854   with full support for type-inference, rather than
  3855 
  3856     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3857 
  3858     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3859     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3860 
  3861     inductive "s z_1 ... z_m"
  3862     intros
  3863       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3864       ...
  3865 
  3866   For backward compatibility, there is a wrapper allowing inductive
  3867   sets to be defined with the new package via
  3868 
  3869     inductive_set
  3870       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3871       for z_1 :: U_1 and ... and z_n :: U_m
  3872     where
  3873       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3874     | ...
  3875 
  3876   or
  3877 
  3878     inductive_set
  3879       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3880       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3881       for z_1 :: U_1 and ... and z_n :: U_m
  3882     where
  3883       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3884     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3885     | ...
  3886 
  3887   if the additional syntax "p ..." is required.
  3888 
  3889   Numerous examples can be found in the subdirectories src/HOL/Auth,
  3890   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  3891 
  3892   INCOMPATIBILITIES:
  3893 
  3894   - Since declaration and definition of inductive sets or predicates
  3895     is no longer separated, abbreviations involving the newly
  3896     introduced sets or predicates must be specified together with the
  3897     introduction rules after the 'where' keyword (see above), rather
  3898     than before the actual inductive definition.
  3899 
  3900   - The variables in induction and elimination rules are now
  3901     quantified in the order of their occurrence in the introduction
  3902     rules, rather than in alphabetical order. Since this may break
  3903     some proofs, these proofs either have to be repaired, e.g. by
  3904     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  3905     statements of the form
  3906 
  3907       case (rule_i a_i_1 ... a_i_{k_i})
  3908 
  3909     or the old order of quantification has to be restored by explicitly adding
  3910     meta-level quantifiers in the introduction rules, i.e.
  3911 
  3912       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  3913 
  3914   - The format of the elimination rules is now
  3915 
  3916       p z_1 ... z_m x_1 ... x_n ==>
  3917         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  3918         ==> ... ==> P
  3919 
  3920     for predicates and
  3921 
  3922       (x_1, ..., x_n) : s z_1 ... z_m ==>
  3923         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  3924         ==> ... ==> P
  3925 
  3926     for sets rather than
  3927 
  3928       x : s z_1 ... z_m ==>
  3929         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  3930         ==> ... ==> P
  3931 
  3932     This may require terms in goals to be expanded to n-tuples
  3933     (e.g. using case_tac or simplification with the split_paired_all
  3934     rule) before the above elimination rule is applicable.
  3935 
  3936   - The elimination or case analysis rules for (mutually) inductive
  3937     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  3938     list of rules "p_1_..._p_k.elims" is no longer available.
  3939 
  3940 * New package "function"/"fun" for general recursive functions,
  3941 supporting mutual and nested recursion, definitions in local contexts,
  3942 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  3943 for small examples, and the separate tutorial on the function
  3944 package. The old recdef "package" is still available as before, but
  3945 users are encouraged to use the new package.
  3946 
  3947 * Method "lexicographic_order" automatically synthesizes termination
  3948 relations as lexicographic combinations of size measures. 
  3949 
  3950 * Case-expressions allow arbitrary constructor-patterns (including
  3951 "_") and take their order into account, like in functional
  3952 programming.  Internally, this is translated into nested
  3953 case-expressions; missing cases are added and mapped to the predefined
  3954 constant "undefined". In complicated cases printing may no longer show
  3955 the original input but the internal form. Lambda-abstractions allow
  3956 the same form of pattern matching: "% pat1 => e1 | ..." is an
  3957 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  3958 variable.
  3959 
  3960 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  3961 is an abbreviation for "of_nat :: nat => int". The simplification
  3962 rules for "of_nat" have been changed to work like "int" did
  3963 previously.  Potential INCOMPATIBILITY:
  3964   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  3965   - of_nat_diff and of_nat_mult are no longer default simp rules
  3966 
  3967 * Method "algebra" solves polynomial equations over (semi)rings using
  3968 Groebner bases. The (semi)ring structure is defined by locales and the
  3969 tool setup depends on that generic context. Installing the method for
  3970 a specific type involves instantiating the locale and possibly adding
  3971 declarations for computation on the coefficients.  The method is
  3972 already instantiated for natural numbers and for the axiomatic class
  3973 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  3974 CALCULEMUS 2007 for the general principles underlying this
  3975 architecture of context-aware proof-tools.
  3976 
  3977 * Method "ferrack" implements quantifier elimination over
  3978 special-purpose dense linear orders using locales (analogous to
  3979 "algebra"). The method is already installed for class
  3980 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  3981 rat, etc.
  3982 
  3983 * Former constant "List.op @" now named "List.append".  Use ML
  3984 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  3985 circumvent possible incompatibilities when working on ML level.
  3986 
  3987 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  3988 
  3989 * New function listsum :: 'a list => 'a for arbitrary monoids.
  3990 Special syntax: "SUM x <- xs. f x" (and latex variants)
  3991 
  3992 * New syntax for Haskell-like list comprehension (input only), eg.
  3993 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  3994 
  3995 * The special syntax for function "filter" has changed from [x :
  3996 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  3997 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  3998 
  3999 * [a..b] is now defined for arbitrary linear orders.  It used to be
  4000 defined on nat only, as an abbreviation for [a..<Suc b]
  4001 INCOMPATIBILITY.
  4002 
  4003 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  4004 
  4005 * New functions "sorted" and "sort" in src/HOL/List.thy.
  4006 
  4007 * New lemma collection field_simps (an extension of ring_simps) for
  4008 manipulating (in)equations involving division. Multiplies with all
  4009 denominators that can be proved to be non-zero (in equations) or
  4010 positive/negative (in inequations).
  4011 
  4012 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  4013 have been improved and renamed to ring_simps, group_simps and
  4014 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  4015 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  4016 
  4017 * Theory Library/Commutative_Ring: switched from recdef to function
  4018 package; constants add, mul, pow now curried.  Infix syntax for
  4019 algebraic operations.
  4020 
  4021 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  4022 INCOMPATIBILITY.
  4023 
  4024 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  4025 INCOMPATIBILITY.
  4026 
  4027 * HOL/records: generalised field-update to take a function on the
  4028 field rather than the new value: r(|A := x|) is translated to A_update
  4029 (K x) r The K-combinator that is internally used is called K_record.
  4030 INCOMPATIBILITY: Usage of the plain update functions has to be
  4031 adapted.
  4032  
  4033 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  4034 * x = 0, which are required for a semiring.  Richer structures do not
  4035 inherit from semiring_0 anymore, because this property is a theorem
  4036 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  4037 there is more to prove, but this is mostly trivial.
  4038 
  4039 * Class "recpower" is generalized to arbitrary monoids, not just
  4040 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  4041 commutativity or semiring properties additionally.
  4042 
  4043 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  4044 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  4045 better use 'abbreviation'.
  4046 
  4047 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  4048 
  4049 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  4050 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  4051 significant changes for setting up numeral syntax for types:
  4052   - New constants Numeral.pred and Numeral.succ instead
  4053       of former Numeral.bin_pred and Numeral.bin_succ.
  4054   - Use integer operations instead of bin_add, bin_mult and so on.
  4055   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  4056   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  4057 
  4058 See src/HOL/Integ/IntArith.thy for an example setup.
  4059 
  4060 * Command 'normal_form' computes the normal form of a term that may
  4061 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  4062 produces ``[b, c, a]'' (without proof).  This command is suitable for
  4063 heavy-duty computations because the functions are compiled to ML
  4064 first.  Correspondingly, a method "normalization" is provided.  See
  4065 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  4066 
  4067 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  4068 25 like -->); output depends on the "iff" print_mode, the default is
  4069 "A = B" (with priority 50).
  4070 
  4071 * Relations less (<) and less_eq (<=) are also available on type bool.
  4072 Modified syntax to disallow nesting without explicit parentheses,
  4073 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  4074 INCOMPATIBILITY.
  4075 
  4076 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  4077 
  4078 * Relation composition operator "op O" now has precedence 75 and binds
  4079 stronger than union and intersection. INCOMPATIBILITY.
  4080 
  4081 * The old set interval syntax "{m..n(}" (and relatives) has been
  4082 removed.  Use "{m..<n}" (and relatives) instead.
  4083 
  4084 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  4085 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  4086 ``declare [[simproc del: neq]]''.
  4087 
  4088 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  4089 True/False.
  4090 
  4091 * Theorem Cons_eq_map_conv no longer declared as "simp".
  4092 
  4093 * Theorem setsum_mult renamed to setsum_right_distrib.
  4094 
  4095 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  4096 ``rule'' method.
  4097 
  4098 * Reimplemented methods "sat" and "satx", with several improvements:
  4099 goals no longer need to be stated as "<prems> ==> False", equivalences
  4100 (i.e. "=" on type bool) are handled, variable names of the form
  4101 "lit_<n>" are no longer reserved, significant speedup.
  4102 
  4103 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  4104 zChaff is still supported as well.
  4105 
  4106 * 'inductive' and 'datatype': provide projections of mutual rules,
  4107 bundled as foo_bar.inducts;
  4108 
  4109 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  4110 Library.
  4111 
  4112 * Library: moved theory Accessible_Part to main HOL.
  4113 
  4114 * Library: added theory Coinductive_List of potentially infinite lists
  4115 as greatest fixed-point.
  4116 
  4117 * Library: added theory AssocList which implements (finite) maps as
  4118 association lists.
  4119 
  4120 * Method "evaluation" solves goals (i.e. a boolean expression)
  4121 efficiently by compiling it to ML.  The goal is "proved" (via an
  4122 oracle) if it evaluates to True.
  4123 
  4124 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  4125 also when invoked by the simplifier.  This results in the Simplifier
  4126 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  4127 Configuration option fast_arith_split_limit=0 recovers the old
  4128 behavior.
  4129 
  4130 * Support for hex (0x20) and binary (0b1001) numerals.
  4131 
  4132 * New method: reify eqs (t), where eqs are equations for an
  4133 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  4134 parameter, computes a term s::'b and a list xs::'a list and proves the
  4135 theorem I xs s = t. This is also known as reification or quoting. The
  4136 resulting theorem is applied to the subgoal to substitute t with I xs
  4137 s.  If t is omitted, the subgoal itself is reified.
  4138 
  4139 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  4140 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  4141 where f is supposed to be a computable function (in the sense of code
  4142 generattion). The method uses reify to compute s and xs as above then
  4143 applies corr_thm and uses normalization by evaluation to "prove" f s =
  4144 r and finally gets the theorem t = r, which is again applied to the
  4145 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  4146 
  4147 * Reflection: Automatic reification now handels binding, an example is
  4148 available in src/HOL/ex/ReflectionEx.thy
  4149 
  4150 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  4151 command 'statespace' that is similar to 'record', but introduces an
  4152 abstract specification based on the locale infrastructure instead of
  4153 HOL types.  This leads to extra flexibility in composing state spaces,
  4154 in particular multiple inheritance and renaming of components.
  4155 
  4156 
  4157 *** HOL-Complex ***
  4158 
  4159 * Hyperreal: Functions root and sqrt are now defined on negative real
  4160 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  4161 Nonnegativity side conditions have been removed from many lemmas, so
  4162 that more subgoals may now be solved by simplification; potential
  4163 INCOMPATIBILITY.
  4164 
  4165 * Real: new type classes formalize real normed vector spaces and
  4166 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  4167 and norm :: 'a => real.
  4168 
  4169 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  4170 reals into other types. The overloaded constant Reals :: 'a set is now
  4171 defined as range of_real; potential INCOMPATIBILITY.
  4172 
  4173 * Real: proper support for ML code generation, including 'quickcheck'.
  4174 Reals are implemented as arbitrary precision rationals.
  4175 
  4176 * Hyperreal: Several constants that previously worked only for the
  4177 reals have been generalized, so they now work over arbitrary vector
  4178 spaces. Type annotations may need to be added in some cases; potential
  4179 INCOMPATIBILITY.
  4180 
  4181   Infinitesimal  :: ('a::real_normed_vector) star set
  4182   HFinite        :: ('a::real_normed_vector) star set
  4183   HInfinite      :: ('a::real_normed_vector) star set
  4184   approx         :: ('a::real_normed_vector) star => 'a star => bool
  4185   monad          :: ('a::real_normed_vector) star => 'a star set
  4186   galaxy         :: ('a::real_normed_vector) star => 'a star set
  4187   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  4188   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  4189   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  4190   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  4191   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  4192   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  4193   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  4194   sgn            :: 'a::real_normed_vector => 'a
  4195   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  4196 
  4197 * Complex: Some complex-specific constants are now abbreviations for
  4198 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  4199 hnorm.  Other constants have been entirely removed in favor of the
  4200 polymorphic versions (INCOMPATIBILITY):
  4201 
  4202   approx        <-- capprox
  4203   HFinite       <-- CFinite
  4204   HInfinite     <-- CInfinite
  4205   Infinitesimal <-- CInfinitesimal
  4206   monad         <-- cmonad
  4207   galaxy        <-- cgalaxy
  4208   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  4209   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  4210   (ns)deriv     <-- (ns)cderiv
  4211 
  4212 
  4213 *** HOL-Algebra ***
  4214 
  4215 * Formalisation of ideals and the quotient construction over rings.
  4216 
  4217 * Order and lattice theory no longer based on records.
  4218 INCOMPATIBILITY.
  4219 
  4220 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  4221 greatest_closed.  INCOMPATIBILITY.
  4222 
  4223 * Method algebra is now set up via an attribute.  For examples see
  4224 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  4225 of algebraic structures.
  4226 
  4227 * Renamed theory CRing to Ring.
  4228 
  4229 
  4230 *** HOL-Nominal ***
  4231 
  4232 * Substantial, yet incomplete support for nominal datatypes (binding
  4233 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  4234 src/HOL/Nominal/Examples.  Prospective users should consult
  4235 http://isabelle.in.tum.de/nominal/
  4236 
  4237 
  4238 *** ML ***
  4239 
  4240 * ML basics: just one true type int, which coincides with IntInf.int
  4241 (even on SML/NJ).
  4242 
  4243 * ML within Isar: antiquotations allow to embed statically-checked
  4244 formal entities in the source, referring to the context available at
  4245 compile-time.  For example:
  4246 
  4247 ML {* @{sort "{zero,one}"} *}
  4248 ML {* @{typ "'a => 'b"} *}
  4249 ML {* @{term "%x. x"} *}
  4250 ML {* @{prop "x == y"} *}
  4251 ML {* @{ctyp "'a => 'b"} *}
  4252 ML {* @{cterm "%x. x"} *}
  4253 ML {* @{cprop "x == y"} *}
  4254 ML {* @{thm asm_rl} *}
  4255 ML {* @{thms asm_rl} *}
  4256 ML {* @{type_name c} *}
  4257 ML {* @{type_syntax c} *}
  4258 ML {* @{const_name c} *}
  4259 ML {* @{const_syntax c} *}
  4260 ML {* @{context} *}
  4261 ML {* @{theory} *}
  4262 ML {* @{theory Pure} *}
  4263 ML {* @{theory_ref} *}
  4264 ML {* @{theory_ref Pure} *}
  4265 ML {* @{simpset} *}
  4266 ML {* @{claset} *}
  4267 ML {* @{clasimpset} *}
  4268 
  4269 The same works for sources being ``used'' within an Isar context.
  4270 
  4271 * ML in Isar: improved error reporting; extra verbosity with
  4272 ML_Context.trace enabled.
  4273 
  4274 * Pure/General/table.ML: the join operations now works via exceptions
  4275 DUP/SAME instead of type option. This is simpler in simple cases, and
  4276 admits slightly more efficient complex applications.
  4277 
  4278 * Pure: 'advanced' translation functions (parse_translation etc.) now
  4279 use Context.generic instead of just theory.
  4280 
  4281 * Pure: datatype Context.generic joins theory/Proof.context and
  4282 provides some facilities for code that works in either kind of
  4283 context, notably GenericDataFun for uniform theory and proof data.
  4284 
  4285 * Pure: simplified internal attribute type, which is now always
  4286 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  4287 local (Proof.context) attributes have been discontinued, while
  4288 minimizing code duplication. Thm.rule_attribute and
  4289 Thm.declaration_attribute build canonical attributes; see also structure
  4290 Context for further operations on Context.generic, notably
  4291 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  4292 declarations and definitions.
  4293 
  4294 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  4295 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  4296 init only required for impure data. INCOMPATIBILITY: empty really need
  4297 to be empty (no dependencies on theory content!)
  4298 
  4299 * Pure/kernel: consts certification ignores sort constraints given in
  4300 signature declarations. (This information is not relevant to the
  4301 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  4302 potential INCOMPATIBILITY.
  4303 
  4304 * Pure: axiomatic type classes are now purely definitional, with
  4305 explicit proofs of class axioms and super class relations performed
  4306 internally. See Pure/axclass.ML for the main internal interfaces --
  4307 notably AxClass.define_class supercedes AxClass.add_axclass, and
  4308 AxClass.axiomatize_class/classrel/arity supersede
  4309 Sign.add_classes/classrel/arities.
  4310 
  4311 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  4312 global/local versions on theory vs. Proof.context have been
  4313 discontinued; Attrib.syntax and Method.syntax have been adapted
  4314 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  4315 attributes, methods, etc.
  4316 
  4317 * Pure: several functions of signature "... -> theory -> theory * ..."
  4318 have been reoriented to "... -> theory -> ... * theory" in order to
  4319 allow natural usage in combination with the ||>, ||>>, |-> and
  4320 fold_map combinators.
  4321 
  4322 * Pure: official theorem names (closed derivations) and additional
  4323 comments (tags) are now strictly separate.  Name hints -- which are
  4324 maintained as tags -- may be attached any time without affecting the
  4325 derivation.
  4326 
  4327 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  4328 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  4329 achieve the old behaviour.
  4330 
  4331 * Pure: the "Goal" constant is now called "prop", supporting a
  4332 slightly more general idea of ``protecting'' meta-level rule
  4333 statements.
  4334 
  4335 * Pure: Logic.(un)varify only works in a global context, which is now
  4336 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  4337 Logic.legacy_(un)varify as temporary workaround.
  4338 
  4339 * Pure: structure Name provides scalable operations for generating
  4340 internal variable names, notably Name.variants etc.  This replaces
  4341 some popular functions from term.ML:
  4342 
  4343   Term.variant		->  Name.variant
  4344   Term.variantlist	->  Name.variant_list
  4345   Term.invent_names	->  Name.invent_list
  4346 
  4347 Note that low-level renaming rarely occurs in new code -- operations
  4348 from structure Variable are used instead (see below).
  4349 
  4350 * Pure: structure Variable provides fundamental operations for proper
  4351 treatment of fixed/schematic variables in a context.  For example,
  4352 Variable.import introduces fixes for schematics of given facts and
  4353 Variable.export reverses the effect (up to renaming) -- this replaces
  4354 various freeze_thaw operations.
  4355 
  4356 * Pure: structure Goal provides simple interfaces for
  4357 init/conclude/finish and tactical prove operations (replacing former
  4358 Tactic.prove).  Goal.prove is the canonical way to prove results
  4359 within a given context; Goal.prove_global is a degraded version for
  4360 theory level goals, including a global Drule.standard.  Note that
  4361 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  4362 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  4363 in a locale context).
  4364 
  4365 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  4366 and type checking (Syntax.check_term etc.), with common combinations
  4367 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  4368 which are considered legacy and await removal.
  4369 
  4370 * Pure/Syntax: generic interfaces for type unchecking
  4371 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  4372 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  4373 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  4374 available for convenience, but refer to the very same operations using
  4375 a mere theory instead of a full context.
  4376 
  4377 * Isar: simplified treatment of user-level errors, using exception
  4378 ERROR of string uniformly.  Function error now merely raises ERROR,
  4379 without any side effect on output channels.  The Isar toplevel takes
  4380 care of proper display of ERROR exceptions.  ML code may use plain
  4381 handle/can/try; cat_error may be used to concatenate errors like this:
  4382 
  4383   ... handle ERROR msg => cat_error msg "..."
  4384 
  4385 Toplevel ML code (run directly or through the Isar toplevel) may be
  4386 embedded into the Isar toplevel with exception display/debug like
  4387 this:
  4388 
  4389   Isar.toplevel (fn () => ...)
  4390 
  4391 INCOMPATIBILITY, removed special transform_error facilities, removed
  4392 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  4393 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  4394 -- use plain ERROR instead.
  4395 
  4396 * Isar: theory setup now has type (theory -> theory), instead of a
  4397 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  4398 
  4399 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  4400 ProofContext.debug/verbose flags.
  4401 
  4402 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  4403 theory before entering a proof state.  Transactions now always see a
  4404 quasi-functional intermediate checkpoint, both in interactive and
  4405 batch mode.
  4406 
  4407 * Isar: simplified interfaces for outer syntax.  Renamed
  4408 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  4409 OuterSyntax.add_parsers -- this functionality is now included in
  4410 OuterSyntax.command etc.  INCOMPATIBILITY.
  4411 
  4412 * Simplifier: the simpset of a running simplification process now
  4413 contains a proof context (cf. Simplifier.the_context), which is the
  4414 very context that the initial simpset has been retrieved from (by
  4415 simpset_of/local_simpset_of).  Consequently, all plug-in components
  4416 (solver, looper etc.) may depend on arbitrary proof data.
  4417 
  4418 * Simplifier.inherit_context inherits the proof context (plus the
  4419 local bounds) of the current simplification process; any simproc
  4420 etc. that calls the Simplifier recursively should do this!  Removed
  4421 former Simplifier.inherit_bounds, which is already included here --
  4422 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  4423 specify an explicit context using Simplifier.context/theory_context.
  4424 
  4425 * Simplifier/Classical Reasoner: more abstract interfaces
  4426 change_simpset/claset for modifying the simpset/claset reference of a
  4427 theory; raw versions simpset/claset_ref etc. have been discontinued --
  4428 INCOMPATIBILITY.
  4429 
  4430 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  4431 "Trueprop" etc.
  4432 
  4433 
  4434 *** System ***
  4435 
  4436 * settings: the default heap location within ISABELLE_HOME_USER now
  4437 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  4438 Isabelle installations.
  4439 
  4440 * isabelle-process: option -S (secure mode) disables some critical
  4441 operations, notably runtime compilation and evaluation of ML source
  4442 code.
  4443 
  4444 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  4445 
  4446 * Support for parallel execution, using native multicore support of
  4447 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  4448 independent theories, according to the given theory header
  4449 specifications. The maximum number of worker threads is specified via
  4450 usedir option -M or the "max-threads" setting in Proof General. A
  4451 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  4452 to 6 on a 8-core machine.  User-code needs to observe certain
  4453 guidelines for thread-safe programming, see appendix A in the Isar
  4454 Implementation manual.
  4455 
  4456 
  4457 
  4458 New in Isabelle2005 (October 2005)
  4459 ----------------------------------
  4460 
  4461 *** General ***
  4462 
  4463 * Theory headers: the new header syntax for Isar theories is
  4464 
  4465   theory <name>
  4466   imports <theory1> ... <theoryN>
  4467   uses <file1> ... <fileM>
  4468   begin
  4469 
  4470 where the 'uses' part is optional.  The previous syntax
  4471 
  4472   theory <name> = <theory1> + ... + <theoryN>:
  4473 
  4474 will disappear in the next release.  Use isatool fixheaders to convert
  4475 existing theory files.  Note that there is no change in ancient
  4476 non-Isar theories now, but these will disappear soon.
  4477 
  4478 * Theory loader: parent theories can now also be referred to via
  4479 relative and absolute paths.
  4480 
  4481 * Command 'find_theorems' searches for a list of criteria instead of a
  4482 list of constants. Known criteria are: intro, elim, dest, name:string,
  4483 simp:term, and any term. Criteria can be preceded by '-' to select
  4484 theorems that do not match. Intro, elim, dest select theorems that
  4485 match the current goal, name:s selects theorems whose fully qualified
  4486 name contain s, and simp:term selects all simplification rules whose
  4487 lhs match term.  Any other term is interpreted as pattern and selects
  4488 all theorems matching the pattern. Available in ProofGeneral under
  4489 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  4490 
  4491   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  4492 
  4493 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  4494 matching the current goal as introduction rule and not having "HOL."
  4495 in their name (i.e. not being defined in theory HOL).
  4496 
  4497 * Command 'thms_containing' has been discontinued in favour of
  4498 'find_theorems'; INCOMPATIBILITY.
  4499 
  4500 * Communication with Proof General is now 8bit clean, which means that
  4501 Unicode text in UTF-8 encoding may be used within theory texts (both
  4502 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4503 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4504 
  4505   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4506   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4507 
  4508 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4509 Classical Reasoner.  Typical big applications run around 2 times
  4510 faster.
  4511 
  4512 
  4513 *** Document preparation ***
  4514 
  4515 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4516 of raw sources.  Only those symbols that do not require additional
  4517 LaTeX packages (depending on comments in isabellesym.sty) are
  4518 displayed properly, everything else is left verbatim.  isatool display
  4519 and isatool print are used as front ends (these are subject to the
  4520 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4521 
  4522 * Command tags control specific markup of certain regions of text,
  4523 notably folding and hiding.  Predefined tags include "theory" (for
  4524 theory begin and end), "proof" for proof commands, and "ML" for
  4525 commands involving ML code; the additional tags "visible" and
  4526 "invisible" are unused by default.  Users may give explicit tag
  4527 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4528 interpretation of tags is determined by the LaTeX job during document
  4529 preparation: see option -V of isatool usedir, or options -n and -t of
  4530 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4531 \isadroptag.
  4532 
  4533 Several document versions may be produced at the same time via isatool
  4534 usedir (the generated index.html will link all of them).  Typical
  4535 specifications include ''-V document=theory,proof,ML'' to present
  4536 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4537 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4538 these parts without any formal replacement text.  The Isabelle site
  4539 default settings produce ''document'' and ''outline'' versions as
  4540 specified above.
  4541 
  4542 * Several new antiquotations:
  4543 
  4544   @{term_type term} prints a term with its type annotated;
  4545 
  4546   @{typeof term} prints the type of a term;
  4547 
  4548   @{const const} is the same as @{term const}, but checks that the
  4549   argument is a known logical constant;
  4550 
  4551   @{term_style style term} and @{thm_style style thm} print a term or
  4552   theorem applying a "style" to it
  4553 
  4554   @{ML text}
  4555 
  4556 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4557 definitions, equations, inequations etc., 'concl' printing only the
  4558 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4559 to print the specified premise.  TermStyle.add_style provides an ML
  4560 interface for introducing further styles.  See also the "LaTeX Sugar"
  4561 document practical applications.  The ML antiquotation prints
  4562 type-checked ML expressions verbatim.
  4563 
  4564 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4565 and 'text' support optional locale specification '(in loc)', which
  4566 specifies the default context for interpreting antiquotations.  For
  4567 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4568 
  4569 * Option 'locale=NAME' of antiquotations specifies an alternative
  4570 context interpreting the subsequent argument.  For example: @{thm
  4571 [locale=lattice] inf_assoc}.
  4572 
  4573 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4574 a proof context.
  4575 
  4576 * Proper output of antiquotations for theory commands involving a
  4577 proof context (such as 'locale' or 'theorem (in loc) ...').
  4578 
  4579 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4580 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4581 
  4582 * isatool usedir: new option -C (default true) controls whether option
  4583 -D should include a copy of the original document directory; -C false
  4584 prevents unwanted effects such as copying of administrative CVS data.
  4585 
  4586 
  4587 *** Pure ***
  4588 
  4589 * Considerably improved version of 'constdefs' command.  Now performs
  4590 automatic type-inference of declared constants; additional support for
  4591 local structure declarations (cf. locales and HOL records), see also
  4592 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4593 sequential dependencies of definitions within a single 'constdefs'
  4594 section; moreover, the declared name needs to be an identifier.  If
  4595 all fails, consider to fall back on 'consts' and 'defs' separately.
  4596 
  4597 * Improved indexed syntax and implicit structures.  First of all,
  4598 indexed syntax provides a notational device for subscripted
  4599 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4600 expressions.  Secondly, in a local context with structure
  4601 declarations, number indexes \<^sub>n or the empty index (default
  4602 number 1) refer to a certain fixed variable implicitly; option
  4603 show_structs controls printing of implicit structures.  Typical
  4604 applications of these concepts involve record types and locales.
  4605 
  4606 * New command 'no_syntax' removes grammar declarations (and
  4607 translations) resulting from the given syntax specification, which is
  4608 interpreted in the same manner as for the 'syntax' command.
  4609 
  4610 * 'Advanced' translation functions (parse_translation etc.) may depend
  4611 on the signature of the theory context being presently used for
  4612 parsing/printing, see also isar-ref manual.
  4613 
  4614 * Improved 'oracle' command provides a type-safe interface to turn an
  4615 ML expression of type theory -> T -> term into a primitive rule of
  4616 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4617 is already included here); see also FOL/ex/IffExample.thy;
  4618 INCOMPATIBILITY.
  4619 
  4620 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4621 before); "cI" is no longer bound, use "c.intro" instead.
  4622 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4623 axclasses vs. locales.
  4624 
  4625 * Improved internal renaming of symbolic identifiers -- attach primes
  4626 instead of base 26 numbers.
  4627 
  4628 * New flag show_question_marks controls printing of leading question
  4629 marks in schematic variable names.
  4630 
  4631 * In schematic variable names, *any* symbol following \<^isub> or
  4632 \<^isup> is now treated as part of the base name.  For example, the
  4633 following works without printing of awkward ".0" indexes:
  4634 
  4635   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4636     by simp
  4637 
  4638 * Inner syntax includes (*(*nested*) comments*).
  4639 
  4640 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4641 annotations as "(00...)".
  4642 
  4643 * Clear separation of logical types and nonterminals, where the latter
  4644 may only occur in 'syntax' specifications or type abbreviations.
  4645 Before that distinction was only partially implemented via type class
  4646 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4647 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4648 exotic syntax specifications may require further adaption
  4649 (e.g. Cube/Cube.thy).
  4650 
  4651 * Removed obsolete type class "logic", use the top sort {} instead.
  4652 Note that non-logical types should be declared as 'nonterminals'
  4653 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4654 specifications.
  4655 
  4656 * Attributes 'induct' and 'cases': type or set names may now be
  4657 locally fixed variables as well.
  4658 
  4659 * Simplifier: can now control the depth to which conditional rewriting
  4660 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4661 Limit.
  4662 
  4663 * Simplifier: simplification procedures may now take the current
  4664 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4665 interface), which is very useful for calling the Simplifier
  4666 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4667 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4668 low-level mk_simproc no longer applies Logic.varify internally, to
  4669 allow for use in a context of fixed variables.
  4670 
  4671 * thin_tac now works even if the assumption being deleted contains !!
  4672 or ==>.  More generally, erule now works even if the major premise of
  4673 the elimination rule contains !! or ==>.
  4674 
  4675 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4676 
  4677 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4678 from Pure, which contains all common declarations already.  Both
  4679 theories are defined via plain Isabelle/Isar .thy files.
  4680 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4681 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4682 use isatool fixcpure to adapt your theory and ML sources.
  4683 
  4684 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4685 selections of theorems in named facts via index ranges.
  4686 
  4687 * 'print_theorems': in theory mode, really print the difference
  4688 wrt. the last state (works for interactive theory development only),
  4689 in proof mode print all local facts (cf. 'print_facts');
  4690 
  4691 * 'hide': option '(open)' hides only base names.
  4692 
  4693 * More efficient treatment of intermediate checkpoints in interactive
  4694 theory development.
  4695 
  4696 * Code generator is now invoked via code_module (incremental code
  4697 generation) and code_library (modular code generation, ML structures
  4698 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4699 must be quoted when used as identifiers.
  4700 
  4701 * New 'value' command for reading, evaluating and printing terms using
  4702 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4703 quoted when used as identifier.
  4704 
  4705 
  4706 *** Locales ***
  4707 
  4708 * New commands for the interpretation of locale expressions in
  4709 theories (1), locales (2) and proof contexts (3).  These generate
  4710 proof obligations from the expression specification.  After the
  4711 obligations have been discharged, theorems of the expression are added
  4712 to the theory, target locale or proof context.  The synopsis of the
  4713 commands is a follows:
  4714 
  4715   (1) interpretation expr inst
  4716   (2) interpretation target < expr
  4717   (3) interpret expr inst
  4718 
  4719 Interpretation in theories and proof contexts require a parameter
  4720 instantiation of terms from the current context.  This is applied to
  4721 specifications and theorems of the interpreted expression.
  4722 Interpretation in locales only permits parameter renaming through the
  4723 locale expression.  Interpretation is smart in that interpretations
  4724 that are active already do not occur in proof obligations, neither are
  4725 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4726 inspect active interpretations of a particular locale.  For details,
  4727 see the Isar Reference manual.  Examples can be found in
  4728 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4729 
  4730 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4731 'interpret' instead.
  4732 
  4733 * New context element 'constrains' for adding type constraints to
  4734 parameters.
  4735 
  4736 * Context expressions: renaming of parameters with syntax
  4737 redeclaration.
  4738 
  4739 * Locale declaration: 'includes' disallowed.
  4740 
  4741 * Proper static binding of attribute syntax -- i.e. types / terms /
  4742 facts mentioned as arguments are always those of the locale definition
  4743 context, independently of the context of later invocations.  Moreover,
  4744 locale operations (renaming and type / term instantiation) are applied
  4745 to attribute arguments as expected.
  4746 
  4747 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4748 actual attributes; rare situations may require Attrib.attribute to
  4749 embed those attributes into Attrib.src that lack concrete syntax.
  4750 Attribute implementations need to cooperate properly with the static
  4751 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4752 Attrib.XXX_thm etc. already do the right thing without further
  4753 intervention.  Only unusual applications -- such as "where" or "of"
  4754 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4755 on the context and the facts involved -- may have to assign parsed
  4756 values to argument tokens explicitly.
  4757 
  4758 * Changed parameter management in theorem generation for long goal
  4759 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4760 theorem statement in rare situations.
  4761 
  4762 * Locale inspection command 'print_locale' omits notes elements.  Use
  4763 'print_locale!' to have them included in the output.
  4764 
  4765 
  4766 *** Provers ***
  4767 
  4768 * Provers/hypsubst.ML: improved version of the subst method, for
  4769 single-step rewriting: it now works in bound variable contexts. New is
  4770 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  4771 rewrite a different subterm than the original subst method, which is
  4772 still available as 'simplesubst'.
  4773 
  4774 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  4775 and quasi orders.
  4776 
  4777 * Provers/trancl.ML: new transitivity reasoner for transitive and
  4778 reflexive-transitive closure of relations.
  4779 
  4780 * Provers/blast.ML: new reference depth_limit to make blast's depth
  4781 limit (previously hard-coded with a value of 20) user-definable.
  4782 
  4783 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  4784 is peformed already.  Object-logics merely need to finish their
  4785 initial simpset configuration as before.  INCOMPATIBILITY.
  4786 
  4787 
  4788 *** HOL ***
  4789 
  4790 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  4791 
  4792   syntax (epsilon)
  4793     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  4794 
  4795 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  4796 and x-symbol; use option '-m epsilon' to get it actually printed.
  4797 Moreover, the mathematically important symbolic identifier \<epsilon>
  4798 becomes available as variable, constant etc.  INCOMPATIBILITY,
  4799 
  4800 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  4801 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  4802 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  4803 support corresponding Isar calculations.
  4804 
  4805 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  4806 instead of ":".
  4807 
  4808 * theory SetInterval: changed the syntax for open intervals:
  4809 
  4810   Old       New
  4811   {..n(}    {..<n}
  4812   {)n..}    {n<..}
  4813   {m..n(}   {m..<n}
  4814   {)m..n}   {m<..n}
  4815   {)m..n(}  {m<..<n}
  4816 
  4817 The old syntax is still supported but will disappear in the next
  4818 release.  For conversion use the following Emacs search and replace
  4819 patterns (these are not perfect but work quite well):
  4820 
  4821   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  4822   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  4823 
  4824 * Theory Commutative_Ring (in Library): method comm_ring for proving
  4825 equalities in commutative rings; method 'algebra' provides a generic
  4826 interface.
  4827 
  4828 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  4829 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  4830 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  4831 be a tuple pattern.
  4832 
  4833 Some new syntax forms are available:
  4834 
  4835   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  4836   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  4837   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  4838   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  4839 
  4840 The latter form "\<Sum>x < k. e" used to be based on a separate
  4841 function "Summation", which has been discontinued.
  4842 
  4843 * theory Finite_Set: in structured induction proofs, the insert case
  4844 is now 'case (insert x F)' instead of the old counterintuitive 'case
  4845 (insert F x)'.
  4846 
  4847 * The 'refute' command has been extended to support a much larger
  4848 fragment of HOL, including axiomatic type classes, constdefs and
  4849 typedefs, inductive datatypes and recursion.
  4850 
  4851 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  4852 Requires zChaff with proof generation to be installed.  See
  4853 HOL/ex/SAT_Examples.thy for examples.
  4854 
  4855 * Datatype induction via method 'induct' now preserves the name of the
  4856 induction variable. For example, when proving P(xs::'a list) by
  4857 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  4858 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  4859 in unstructured proof scripts.
  4860 
  4861 * Reworked implementation of records.  Improved scalability for
  4862 records with many fields, avoiding performance problems for type
  4863 inference. Records are no longer composed of nested field types, but
  4864 of nested extension types. Therefore the record type only grows linear
  4865 in the number of extensions and not in the number of fields.  The
  4866 top-level (users) view on records is preserved.  Potential
  4867 INCOMPATIBILITY only in strange cases, where the theory depends on the
  4868 old record representation. The type generated for a record is called
  4869 <record_name>_ext_type.
  4870 
  4871 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  4872 proofs triggered by a record definition or a simproc (if
  4873 quick_and_dirty is enabled).  Definitions of large records can take
  4874 quite long.
  4875 
  4876 New simproc record_upd_simproc for simplification of multiple record
  4877 updates enabled by default.  Moreover, trivial updates are also
  4878 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  4879 occasionally, since simplification is more powerful by default.
  4880 
  4881 * typedef: proper support for polymorphic sets, which contain extra
  4882 type-variables in the term.
  4883 
  4884 * Simplifier: automatically reasons about transitivity chains
  4885 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  4886 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  4887 old proofs break occasionally as simplification may now solve more
  4888 goals than previously.
  4889 
  4890 * Simplifier: converts x <= y into x = y if assumption y <= x is
  4891 present.  Works for all partial orders (class "order"), in particular
  4892 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  4893 just like y <= x.
  4894 
  4895 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  4896 bound variable or a constant then the let is unfolded.  Otherwise
  4897 first a is simplified to b, and then f b is simplified to g. If
  4898 possible we abstract b from g arriving at "let x = b in h x",
  4899 otherwise we unfold the let and arrive at g.  The simproc can be
  4900 enabled/disabled by the reference use_let_simproc.  Potential
  4901 INCOMPATIBILITY since simplification is more powerful by default.
  4902 
  4903 * Classical reasoning: the meson method now accepts theorems as arguments.
  4904 
  4905 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  4906 jobs to provide advice on the provability of subgoals.
  4907 
  4908 * Theory OrderedGroup and Ring_and_Field: various additions and
  4909 improvements to faciliate calculations involving equalities and
  4910 inequalities.
  4911 
  4912 The following theorems have been eliminated or modified
  4913 (INCOMPATIBILITY):
  4914 
  4915   abs_eq             now named abs_of_nonneg
  4916   abs_of_ge_0        now named abs_of_nonneg
  4917   abs_minus_eq       now named abs_of_nonpos
  4918   imp_abs_id         now named abs_of_nonneg
  4919   imp_abs_neg_id     now named abs_of_nonpos
  4920   mult_pos           now named mult_pos_pos
  4921   mult_pos_le        now named mult_nonneg_nonneg
  4922   mult_pos_neg_le    now named mult_nonneg_nonpos
  4923   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  4924   mult_neg           now named mult_neg_neg
  4925   mult_neg_le        now named mult_nonpos_nonpos
  4926 
  4927 * The following lemmas in Ring_and_Field have been added to the simplifier:
  4928      
  4929      zero_le_square
  4930      not_square_less_zero 
  4931 
  4932   The following lemmas have been deleted from Real/RealPow:
  4933   
  4934      realpow_zero_zero
  4935      realpow_two
  4936      realpow_less
  4937      zero_le_power
  4938      realpow_two_le
  4939      abs_realpow_two
  4940      realpow_two_abs     
  4941 
  4942 * Theory Parity: added rules for simplifying exponents.
  4943 
  4944 * Theory List:
  4945 
  4946 The following theorems have been eliminated or modified
  4947 (INCOMPATIBILITY):
  4948 
  4949   list_all_Nil       now named list_all.simps(1)
  4950   list_all_Cons      now named list_all.simps(2)
  4951   list_all_conv      now named list_all_iff
  4952   set_mem_eq         now named mem_iff
  4953 
  4954 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  4955 asymptotic "big O" calculations.  See the notes in BigO.thy.
  4956 
  4957 
  4958 *** HOL-Complex ***
  4959 
  4960 * Theory RealDef: better support for embedding natural numbers and
  4961 integers in the reals.
  4962 
  4963 The following theorems have been eliminated or modified
  4964 (INCOMPATIBILITY):
  4965 
  4966   exp_ge_add_one_self  now requires no hypotheses
  4967   real_of_int_add      reversed direction of equality (use [symmetric])
  4968   real_of_int_minus    reversed direction of equality (use [symmetric])
  4969   real_of_int_diff     reversed direction of equality (use [symmetric])
  4970   real_of_int_mult     reversed direction of equality (use [symmetric])
  4971 
  4972 * Theory RComplete: expanded support for floor and ceiling functions.
  4973 
  4974 * Theory Ln is new, with properties of the natural logarithm
  4975 
  4976 * Hyperreal: There is a new type constructor "star" for making
  4977 nonstandard types.  The old type names are now type synonyms:
  4978 
  4979   hypreal = real star
  4980   hypnat = nat star
  4981   hcomplex = complex star
  4982 
  4983 * Hyperreal: Many groups of similarly-defined constants have been
  4984 replaced by polymorphic versions (INCOMPATIBILITY):
  4985 
  4986   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  4987 
  4988   starset      <-- starsetNat, starsetC
  4989   *s*          <-- *sNat*, *sc*
  4990   starset_n    <-- starsetNat_n, starsetC_n
  4991   *sn*         <-- *sNatn*, *scn*
  4992   InternalSets <-- InternalNatSets, InternalCSets
  4993 
  4994   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  4995   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  4996   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  4997   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  4998   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  4999 
  5000 * Hyperreal: Many type-specific theorems have been removed in favor of
  5001 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  5002 
  5003   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  5004   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  5005   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  5006   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  5007   right_minus <-- hypreal_add_minus
  5008   left_minus <-- {hypreal,hcomplex}_add_minus_left
  5009   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  5010   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  5011   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  5012   mult_1_right <-- hcomplex_mult_one_right
  5013   mult_zero_left <-- hcomplex_mult_zero_left
  5014   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  5015   right_distrib <-- hypnat_add_mult_distrib2
  5016   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  5017   right_inverse <-- hypreal_mult_inverse
  5018   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  5019   order_refl <-- {hypreal,hypnat}_le_refl
  5020   order_trans <-- {hypreal,hypnat}_le_trans
  5021   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  5022   order_less_le <-- {hypreal,hypnat}_less_le
  5023   linorder_linear <-- {hypreal,hypnat}_le_linear
  5024   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  5025   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  5026   add_nonneg_nonneg <-- hypreal_le_add_order
  5027 
  5028 * Hyperreal: Separate theorems having to do with type-specific
  5029 versions of constants have been merged into theorems that apply to the
  5030 new polymorphic constants (INCOMPATIBILITY):
  5031 
  5032   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  5033   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  5034   STAR_Un <-- {STAR,NatStar,STARC}_Un
  5035   STAR_Int <-- {STAR,NatStar,STARC}_Int
  5036   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  5037   STAR_subset <-- {STAR,NatStar,STARC}_subset
  5038   STAR_mem <-- {STAR,NatStar,STARC}_mem
  5039   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  5040   STAR_diff <-- {STAR,STARC}_diff
  5041   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  5042     STARC_hcomplex_of_complex}_image_subset
  5043   starset_n_Un <-- starset{Nat,C}_n_Un
  5044   starset_n_Int <-- starset{Nat,C}_n_Int
  5045   starset_n_Compl <-- starset{Nat,C}_n_Compl
  5046   starset_n_diff <-- starset{Nat,C}_n_diff
  5047   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  5048   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  5049   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  5050   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  5051   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  5052   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  5053   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  5054   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  5055   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  5056   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  5057   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  5058   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  5059   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  5060   starfun_diff <-- starfun{C,RC,CR}_diff
  5061   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  5062   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  5063   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  5064   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  5065   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  5066   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  5067   starfun_Id <-- starfunC_Id
  5068   starfun_approx <-- starfun{Nat,CR}_approx
  5069   starfun_capprox <-- starfun{C,RC}_capprox
  5070   starfun_abs <-- starfunNat_rabs
  5071   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  5072   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  5073   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  5074   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  5075   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  5076   starfun_add_approx <-- starfunCR_add_approx
  5077   starfun_inverse_inverse <-- starfunC_inverse_inverse
  5078   starfun_divide <-- starfun{C,CR,RC}_divide
  5079   starfun_n <-- starfun{Nat,C}_n
  5080   starfun_n_mult <-- starfun{Nat,C}_n_mult
  5081   starfun_n_add <-- starfun{Nat,C}_n_add
  5082   starfun_n_add_minus <-- starfunNat_n_add_minus
  5083   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  5084   starfun_n_minus <-- starfun{Nat,C}_n_minus
  5085   starfun_n_eq <-- starfun{Nat,C}_n_eq
  5086 
  5087   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  5088   star_n_minus <-- {hypreal,hcomplex}_minus
  5089   star_n_diff <-- {hypreal,hcomplex}_diff
  5090   star_n_mult <-- {hypreal,hcomplex}_mult
  5091   star_n_inverse <-- {hypreal,hcomplex}_inverse
  5092   star_n_le <-- {hypreal,hypnat}_le
  5093   star_n_less <-- {hypreal,hypnat}_less
  5094   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  5095   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  5096   star_n_abs <-- hypreal_hrabs
  5097   star_n_divide <-- hcomplex_divide
  5098 
  5099   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  5100   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  5101   star_of_diff <-- hypreal_of_real_diff
  5102   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  5103   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  5104   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  5105   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  5106   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  5107   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  5108   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  5109   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  5110   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  5111   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  5112   star_of_number_of <-- {hypreal,hcomplex}_number_of
  5113   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  5114   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  5115   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  5116   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  5117   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  5118   star_of_power <-- hypreal_of_real_power
  5119   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  5120 
  5121 * Hyperreal: new method "transfer" that implements the transfer
  5122 principle of nonstandard analysis. With a subgoal that mentions
  5123 nonstandard types like "'a star", the command "apply transfer"
  5124 replaces it with an equivalent one that mentions only standard types.
  5125 To be successful, all free variables must have standard types; non-
  5126 standard variables must have explicit universal quantifiers.
  5127 
  5128 * Hyperreal: A theory of Taylor series.
  5129 
  5130 
  5131 *** HOLCF ***
  5132 
  5133 * Discontinued special version of 'constdefs' (which used to support
  5134 continuous functions) in favor of the general Pure one with full
  5135 type-inference.
  5136 
  5137 * New simplification procedure for solving continuity conditions; it
  5138 is much faster on terms with many nested lambda abstractions (cubic
  5139 instead of exponential time).
  5140 
  5141 * New syntax for domain package: selector names are now optional.
  5142 Parentheses should be omitted unless argument is lazy, for example:
  5143 
  5144   domain 'a stream = cons "'a" (lazy "'a stream")
  5145 
  5146 * New command 'fixrec' for defining recursive functions with pattern
  5147 matching; defining multiple functions with mutual recursion is also
  5148 supported.  Patterns may include the constants cpair, spair, up, sinl,
  5149 sinr, or any data constructor defined by the domain package. The given
  5150 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  5151 syntax and examples.
  5152 
  5153 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  5154 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  5155 but the proof obligation additionally includes an admissibility
  5156 requirement. The packages generate instances of class cpo or pcpo,
  5157 with continuity and strictness theorems for Rep and Abs.
  5158 
  5159 * HOLCF: Many theorems have been renamed according to a more standard naming
  5160 scheme (INCOMPATIBILITY):
  5161 
  5162   foo_inject:  "foo$x = foo$y ==> x = y"
  5163   foo_eq:      "(foo$x = foo$y) = (x = y)"
  5164   foo_less:    "(foo$x << foo$y) = (x << y)"
  5165   foo_strict:  "foo$UU = UU"
  5166   foo_defined: "... ==> foo$x ~= UU"
  5167   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  5168 
  5169 
  5170 *** ZF ***
  5171 
  5172 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  5173 including the First Isomorphism Theorem (on quotienting by the kernel
  5174 of a homomorphism).
  5175 
  5176 * ZF/Simplifier: install second copy of type solver that actually
  5177 makes use of TC rules declared to Isar proof contexts (or locales);
  5178 the old version is still required for ML proof scripts.
  5179 
  5180 
  5181 *** Cube ***
  5182 
  5183 * Converted to Isar theory format; use locales instead of axiomatic
  5184 theories.
  5185 
  5186 
  5187 *** ML ***
  5188 
  5189 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  5190 for ||>, ||>>, |>>,
  5191 
  5192 * Pure/library.ML no longer defines its own option datatype, but uses
  5193 that of the SML basis, which has constructors NONE and SOME instead of
  5194 None and Some, as well as exception Option.Option instead of OPTION.
  5195 The functions the, if_none, is_some, is_none have been adapted
  5196 accordingly, while Option.map replaces apsome.
  5197 
  5198 * Pure/library.ML: the exception LIST has been given up in favour of
  5199 the standard exceptions Empty and Subscript, as well as
  5200 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  5201 superceded by the standard hd and tl functions etc.
  5202 
  5203 A number of basic list functions are no longer exported to the ML
  5204 toplevel, as they are variants of predefined functions.  The following
  5205 suggests how one can translate existing code:
  5206 
  5207     rev_append xs ys = List.revAppend (xs, ys)
  5208     nth_elem (i, xs) = List.nth (xs, i)
  5209     last_elem xs = List.last xs
  5210     flat xss = List.concat xss
  5211     seq fs = List.app fs
  5212     partition P xs = List.partition P xs
  5213     mapfilter f xs = List.mapPartial f xs
  5214 
  5215 * Pure/library.ML: several combinators for linear functional
  5216 transformations, notably reverse application and composition:
  5217 
  5218   x |> f                f #> g
  5219   (x, y) |-> f          f #-> g
  5220 
  5221 * Pure/library.ML: introduced/changed precedence of infix operators:
  5222 
  5223   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  5224   infix 2 ?;
  5225   infix 3 o oo ooo oooo;
  5226   infix 4 ~~ upto downto;
  5227 
  5228 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  5229 infix operators.
  5230 
  5231 * Pure/library.ML: natural list combinators fold, fold_rev, and
  5232 fold_map support linear functional transformations and nesting.  For
  5233 example:
  5234 
  5235   fold f [x1, ..., xN] y =
  5236     y |> f x1 |> ... |> f xN
  5237 
  5238   (fold o fold) f [xs1, ..., xsN] y =
  5239     y |> fold f xs1 |> ... |> fold f xsN
  5240 
  5241   fold f [x1, ..., xN] =
  5242     f x1 #> ... #> f xN
  5243 
  5244   (fold o fold) f [xs1, ..., xsN] =
  5245     fold f xs1 #> ... #> fold f xsN
  5246 
  5247 * Pure/library.ML: the following selectors on type 'a option are
  5248 available:
  5249 
  5250   the:               'a option -> 'a  (*partial*)
  5251   these:             'a option -> 'a  where 'a = 'b list
  5252   the_default: 'a -> 'a option -> 'a
  5253   the_list:          'a option -> 'a list
  5254 
  5255 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5256 basic operations for association lists, following natural argument
  5257 order; moreover the explicit equality predicate passed here avoids
  5258 potentially expensive polymorphic runtime equality checks.
  5259 The old functions may be expressed as follows:
  5260 
  5261   assoc = uncurry (AList.lookup (op =))
  5262   assocs = these oo AList.lookup (op =)
  5263   overwrite = uncurry (AList.update (op =)) o swap
  5264 
  5265 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5266 
  5267   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  5268   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  5269 
  5270 replacing make_keylist and keyfilter (occassionally used)
  5271 Naive rewrites:
  5272 
  5273   make_keylist = AList.make
  5274   keyfilter = AList.find (op =)
  5275 
  5276 * eq_fst and eq_snd now take explicit equality parameter, thus
  5277   avoiding eqtypes. Naive rewrites:
  5278 
  5279     eq_fst = eq_fst (op =)
  5280     eq_snd = eq_snd (op =)
  5281 
  5282 * Removed deprecated apl and apr (rarely used).
  5283   Naive rewrites:
  5284 
  5285     apl (n, op) =>>= curry op n
  5286     apr (op, m) =>>= fn n => op (n, m)
  5287 
  5288 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  5289 provides a reasonably efficient light-weight implementation of sets as
  5290 lists.
  5291 
  5292 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  5293 few new operations; existing lookup and update are now curried to
  5294 follow natural argument order (for use with fold etc.);
  5295 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  5296 
  5297 * Pure/General: output via the Isabelle channels of
  5298 writeln/warning/error etc. is now passed through Output.output, with a
  5299 hook for arbitrary transformations depending on the print_mode
  5300 (cf. Output.add_mode -- the first active mode that provides a output
  5301 function wins).  Already formatted output may be embedded into further
  5302 text via Output.raw; the result of Pretty.string_of/str_of and derived
  5303 functions (string_of_term/cterm/thm etc.) is already marked raw to
  5304 accommodate easy composition of diagnostic messages etc.  Programmers
  5305 rarely need to care about Output.output or Output.raw at all, with
  5306 some notable exceptions: Output.output is required when bypassing the
  5307 standard channels (writeln etc.), or in token translations to produce
  5308 properly formatted results; Output.raw is required when capturing
  5309 already output material that will eventually be presented to the user
  5310 a second time.  For the default print mode, both Output.output and
  5311 Output.raw have no effect.
  5312 
  5313 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  5314 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  5315 cumulative results are displayed at the end of a batch session.
  5316 
  5317 * Pure/General: File.sysify_path and File.quote_sysify path have been
  5318 replaced by File.platform_path and File.shell_path (with appropriate
  5319 hooks).  This provides a clean interface for unusual systems where the
  5320 internal and external process view of file names are different.
  5321 
  5322 * Pure: more efficient orders for basic syntactic entities: added
  5323 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  5324 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  5325 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  5326 orders now -- potential INCOMPATIBILITY for code that depends on a
  5327 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  5328 Library.sort_strings on result).
  5329 
  5330 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  5331 fold_types traverse types/terms from left to right, observing natural
  5332 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  5333 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  5334 
  5335 * Pure: name spaces have been refined, with significant changes of the
  5336 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  5337 to extern(_table).  The plain name entry path is superceded by a
  5338 general 'naming' context, which also includes the 'policy' to produce
  5339 a fully qualified name and external accesses of a fully qualified
  5340 name; NameSpace.extend is superceded by context dependent
  5341 Sign.declare_name.  Several theory and proof context operations modify
  5342 the naming context.  Especially note Theory.restore_naming and
  5343 ProofContext.restore_naming to get back to a sane state; note that
  5344 Theory.add_path is no longer sufficient to recover from
  5345 Theory.absolute_path in particular.
  5346 
  5347 * Pure: new flags short_names (default false) and unique_names
  5348 (default true) for controlling output of qualified names.  If
  5349 short_names is set, names are printed unqualified.  If unique_names is
  5350 reset, the name prefix is reduced to the minimum required to achieve
  5351 the original result when interning again, even if there is an overlap
  5352 with earlier declarations.
  5353 
  5354 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  5355 now 'extend', and 'merge' gets an additional Pretty.pp argument
  5356 (useful for printing error messages).  INCOMPATIBILITY.
  5357 
  5358 * Pure: major reorganization of the theory context.  Type Sign.sg and
  5359 Theory.theory are now identified, referring to the universal
  5360 Context.theory (see Pure/context.ML).  Actual signature and theory
  5361 content is managed as theory data.  The old code and interfaces were
  5362 spread over many files and structures; the new arrangement introduces
  5363 considerable INCOMPATIBILITY to gain more clarity:
  5364 
  5365   Context -- theory management operations (name, identity, inclusion,
  5366     parents, ancestors, merge, etc.), plus generic theory data;
  5367 
  5368   Sign -- logical signature and syntax operations (declaring consts,
  5369     types, etc.), plus certify/read for common entities;
  5370 
  5371   Theory -- logical theory operations (stating axioms, definitions,
  5372     oracles), plus a copy of logical signature operations (consts,
  5373     types, etc.); also a few basic management operations (Theory.copy,
  5374     Theory.merge, etc.)
  5375 
  5376 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  5377 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  5378 for convenience -- they merely return the theory.
  5379 
  5380 * Pure: type Type.tsig is superceded by theory in most interfaces.
  5381 
  5382 * Pure: the Isar proof context type is already defined early in Pure
  5383 as Context.proof (note that ProofContext.context and Proof.context are
  5384 aliases, where the latter is the preferred name).  This enables other
  5385 Isabelle components to refer to that type even before Isar is present.
  5386 
  5387 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  5388 typeK, constK, axiomK, oracleK), but provide explicit operations for
  5389 any of these kinds.  For example, Sign.intern typeK is now
  5390 Sign.intern_type, Theory.hide_space Sign.typeK is now
  5391 Theory.hide_types.  Also note that former
  5392 Theory.hide_classes/types/consts are now
  5393 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  5394 internalize their arguments!  INCOMPATIBILITY.
  5395 
  5396 * Pure: get_thm interface (of PureThy and ProofContext) expects
  5397 datatype thmref (with constructors Name and NameSelection) instead of
  5398 plain string -- INCOMPATIBILITY;
  5399 
  5400 * Pure: cases produced by proof methods specify options, where NONE
  5401 means to remove case bindings -- INCOMPATIBILITY in
  5402 (RAW_)METHOD_CASES.
  5403 
  5404 * Pure: the following operations retrieve axioms or theorems from a
  5405 theory node or theory hierarchy, respectively:
  5406 
  5407   Theory.axioms_of: theory -> (string * term) list
  5408   Theory.all_axioms_of: theory -> (string * term) list
  5409   PureThy.thms_of: theory -> (string * thm) list
  5410   PureThy.all_thms_of: theory -> (string * thm) list
  5411 
  5412 * Pure: print_tac now outputs the goal through the trace channel.
  5413 
  5414 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  5415 Reference Toplevel.debug (default false) controls detailed printing
  5416 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  5417 controls execution profiling -- set to 1 for time and 2 for space
  5418 (both increase the runtime).
  5419 
  5420 * Isar session: The initial use of ROOT.ML is now always timed,
  5421 i.e. the log will show the actual process times, in contrast to the
  5422 elapsed wall-clock time that the outer shell wrapper produces.
  5423 
  5424 * Simplifier: improved handling of bound variables (nameless
  5425 representation, avoid allocating new strings).  Simprocs that invoke
  5426 the Simplifier recursively should use Simplifier.inherit_bounds to
  5427 avoid local name clashes.  Failure to do so produces warnings
  5428 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  5429 for further details.
  5430 
  5431 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  5432 bindings for all theorems stored within a given theory; this may help
  5433 in porting non-Isar theories to Isar ones, while keeping ML proof
  5434 scripts for the time being.
  5435 
  5436 * ML operator HTML.with_charset specifies the charset begin used for
  5437 generated HTML files.  For example:
  5438 
  5439   HTML.with_charset "utf-8" use_thy "Hebrew";
  5440   HTML.with_charset "utf-8" use_thy "Chinese";
  5441 
  5442 
  5443 *** System ***
  5444 
  5445 * Allow symlinks to all proper Isabelle executables (Isabelle,
  5446 isabelle, isatool etc.).
  5447 
  5448 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  5449 isatool doc, isatool mkdir, display_drafts etc.).
  5450 
  5451 * isatool usedir: option -f allows specification of the ML file to be
  5452 used by Isabelle; default is ROOT.ML.
  5453 
  5454 * New isatool version outputs the version identifier of the Isabelle
  5455 distribution being used.
  5456 
  5457 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  5458 (containing Boolean satisfiability problems) into Isabelle/HOL
  5459 theories.
  5460 
  5461 
  5462 
  5463 New in Isabelle2004 (April 2004)
  5464 --------------------------------
  5465 
  5466 *** General ***
  5467 
  5468 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  5469   Replaces linorder.ML.
  5470 
  5471 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  5472   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  5473   (\<a>...\<z>), are now considered normal letters, and can therefore
  5474   be used anywhere where an ASCII letter (a...zA...Z) has until
  5475   now. COMPATIBILITY: This obviously changes the parsing of some
  5476   terms, especially where a symbol has been used as a binder, say
  5477   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  5478   as an identifier.  Fix it by inserting a space around former
  5479   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  5480   existing theory and ML files.
  5481 
  5482 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  5483 
  5484 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  5485   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  5486   a normal (but invisible) letter. For multiple letter subscripts repeat
  5487   \<^isub> like this: x\<^isub>1\<^isub>2.
  5488 
  5489 * Pure: There are now sub-/superscripts that can span more than one
  5490   character. Text between \<^bsub> and \<^esub> is set in subscript in
  5491   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  5492   superscript. The new control characters are not identifier parts.
  5493 
  5494 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5495   content of "..." to the latex file instead of \isacntrl... . The "..."
  5496   may consist of any printable characters excluding the end bracket >.
  5497 
  5498 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5499   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5500   declare constants "final", which prevents their being given a definition
  5501   later.  It is useful for constants whose behaviour is fixed axiomatically
  5502   rather than definitionally, such as the meta-logic connectives.
  5503 
  5504 * Pure: 'instance' now handles general arities with general sorts
  5505   (i.e. intersections of classes),
  5506 
  5507 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5508   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5509   It can be changed to alter the colors/layout of generated pages.
  5510 
  5511 
  5512 *** Isar ***
  5513 
  5514 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5515   cut_tac, subgoal_tac and thin_tac:
  5516   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5517     locales are no longer forced to write Isar proof scripts.
  5518     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5519     emulations.
  5520   - INCOMPATIBILITY: names of variables to be instantiated may no
  5521     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5522     This is consistent with the instantiation attribute "where".
  5523 
  5524 * Attributes "where" and "of":
  5525   - Now take type variables of instantiated theorem into account when reading
  5526     the instantiation string.  This fixes a bug that caused instantiated
  5527     theorems to have too special types in some circumstances.
  5528   - "where" permits explicit instantiations of type variables.
  5529 
  5530 * Calculation commands "moreover" and "also" no longer interfere with
  5531   current facts ("this"), admitting arbitrary combinations with "then"
  5532   and derived forms.
  5533 
  5534 * Locales:
  5535   - Goal statements involving the context element "includes" no longer
  5536     generate theorems with internal delta predicates (those ending on
  5537     "_axioms") in the premise.
  5538     Resolve particular premise with <locale>.intro to obtain old form.
  5539   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5540     specification and "includes" elements in goal statement.
  5541   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5542     [intro?] and [elim?] (respectively) by default.
  5543   - Experimental command for instantiation of locales in proof contexts:
  5544         instantiate <label>[<attrs>]: <loc>
  5545     Instantiates locale <loc> and adds all its theorems to the current context
  5546     taking into account their attributes.  Label and attrs are optional
  5547     modifiers, like in theorem declarations.  If present, names of
  5548     instantiated theorems are qualified with <label>, and the attributes
  5549     <attrs> are applied after any attributes these theorems might have already.
  5550       If the locale has assumptions, a chained fact of the form
  5551     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5552     are derived.  The command does not support old-style locales declared
  5553     with "locale (open)".
  5554       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5555 
  5556 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5557   (Isar) contexts.
  5558 
  5559 
  5560 *** HOL ***
  5561 
  5562 * Proof import: new image HOL4 contains the imported library from
  5563   the HOL4 system with about 2500 theorems. It is imported by
  5564   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5565   can be used like any other Isabelle image.  See
  5566   HOL/Import/HOL/README for more information.
  5567 
  5568 * Simplifier:
  5569   - Much improved handling of linear and partial orders.
  5570     Reasoners for linear and partial orders are set up for type classes
  5571     "linorder" and "order" respectively, and are added to the default simpset
  5572     as solvers.  This means that the simplifier can build transitivity chains
  5573     to solve goals from the assumptions.
  5574   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5575     of blast or auto after simplification become unnecessary because the goal
  5576     is solved by simplification already.
  5577 
  5578 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5579     all proved in axiomatic type classes for semirings, rings and fields.
  5580 
  5581 * Numerics:
  5582   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5583     now formalized using the Ring_and_Field theory mentioned above.
  5584   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5585     than before, because now they are set up once in a generic manner.
  5586   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5587     Look for the general versions in Ring_and_Field (and Power if they concern
  5588     exponentiation).
  5589 
  5590 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5591 
  5592 * Records:
  5593   - Record types are now by default printed with their type abbreviation
  5594     instead of the list of all field types. This can be configured via
  5595     the reference "print_record_type_abbr".
  5596   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5597     (not enabled by default).
  5598   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5599     EX x. x = sel r to True (not enabled by default).
  5600   - Tactic "record_split_simp_tac" to split and simplify records added.
  5601 
  5602 * 'specification' command added, allowing for definition by
  5603   specification.  There is also an 'ax_specification' command that
  5604   introduces the new constants axiomatically.
  5605 
  5606 * arith(_tac) is now able to generate counterexamples for reals as well.
  5607 
  5608 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5609 
  5610 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5611   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5612 
  5613 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5614   matrix theory to linear programming.
  5615 
  5616 * Unions and Intersections:
  5617   The latex output syntax of UN and INT has been changed
  5618   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5619   i.e. the index formulae has become a subscript.
  5620   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5621 
  5622 * Unions and Intersections over Intervals:
  5623   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5624   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5625   like in normal math, and corresponding versions for < and for intersection.
  5626 
  5627 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5628   lexicographic dictonary ordering has been added as "lexord".
  5629 
  5630 * ML: the legacy theory structures Int and List have been removed. They had
  5631   conflicted with ML Basis Library structures having the same names.
  5632 
  5633 * 'refute' command added to search for (finite) countermodels.  Only works
  5634   for a fragment of HOL.  The installation of an external SAT solver is
  5635   highly recommended.  See "HOL/Refute.thy" for details.
  5636 
  5637 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5638   formulae under an assignment of free variables to random values.
  5639   In contrast to 'refute', it can deal with inductive datatypes,
  5640   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5641   for examples.
  5642 
  5643 
  5644 *** HOLCF ***
  5645 
  5646 * Streams now come with concatenation and are part of the HOLCF image
  5647 
  5648 
  5649 
  5650 New in Isabelle2003 (May 2003)
  5651 ------------------------------
  5652 
  5653 *** General ***
  5654 
  5655 * Provers/simplifier:
  5656 
  5657   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5658     Assumptions are now subject to complete mutual simplification,
  5659     not just from left to right. The simplifier now preserves
  5660     the order of assumptions.
  5661 
  5662     Potential INCOMPATIBILITY:
  5663 
  5664     -- simp sometimes diverges where the old version did
  5665        not, e.g. invoking simp on the goal
  5666 
  5667         [| P (f x); y = x; f x = f y |] ==> Q
  5668 
  5669        now gives rise to the infinite reduction sequence
  5670 
  5671         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5672 
  5673        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5674        kind of problem.
  5675 
  5676     -- Tactics combining classical reasoner and simplification (such as auto)
  5677        are also affected by this change, because many of them rely on
  5678        simp. They may sometimes diverge as well or yield a different numbers
  5679        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5680        in case of problems. Sometimes subsequent calls to the classical
  5681        reasoner will fail because a preceeding call to the simplifier too
  5682        eagerly simplified the goal, e.g. deleted redundant premises.
  5683 
  5684   - The simplifier trace now shows the names of the applied rewrite rules
  5685 
  5686   - You can limit the number of recursive invocations of the simplifier
  5687     during conditional rewriting (where the simplifie tries to solve the
  5688     conditions before applying the rewrite rule):
  5689     ML "simp_depth_limit := n"
  5690     where n is an integer. Thus you can force termination where previously
  5691     the simplifier would diverge.
  5692 
  5693   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5694 
  5695   - No longer aborts on failed congruence proof.  Instead, the
  5696     congruence is ignored.
  5697 
  5698 * Pure: New generic framework for extracting programs from constructive
  5699   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5700   as HOL/Extraction for some case studies.
  5701 
  5702 * Pure: The main goal of the proof state is no longer shown by default, only
  5703 the subgoals. This behaviour is controlled by a new flag.
  5704    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5705 (ML: Proof.show_main_goal).
  5706 
  5707 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5708 rules whose conclusion matches subgoal 1:
  5709       PG menu: Isabelle/Isar -> Show me -> matching rules
  5710 The rules are ordered by how closely they match the subgoal.
  5711 In particular, rules that solve a subgoal outright are displayed first
  5712 (or rather last, the way they are printed).
  5713 (ML: ProofGeneral.print_intros())
  5714 
  5715 * Pure: New flag trace_unify_fail causes unification to print
  5716 diagnostic information (PG: in trace buffer) when it fails. This is
  5717 useful for figuring out why single step proofs like rule, erule or
  5718 assumption failed.
  5719 
  5720 * Pure: Locale specifications now produce predicate definitions
  5721 according to the body of text (covering assumptions modulo local
  5722 definitions); predicate "loc_axioms" covers newly introduced text,
  5723 while "loc" is cumulative wrt. all included locale expressions; the
  5724 latter view is presented only on export into the global theory
  5725 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5726 on the old view without predicates;
  5727 
  5728 * Pure: predefined locales "var" and "struct" are useful for sharing
  5729 parameters (as in CASL, for example); just specify something like
  5730 ``var x + var y + struct M'' as import;
  5731 
  5732 * Pure: improved thms_containing: proper indexing of facts instead of
  5733 raw theorems; check validity of results wrt. current name space;
  5734 include local facts of proof configuration (also covers active
  5735 locales), cover fixed variables in index; may use "_" in term
  5736 specification; an optional limit for the number of printed facts may
  5737 be given (the default is 40);
  5738 
  5739 * Pure: disallow duplicate fact bindings within new-style theory files
  5740 (batch-mode only);
  5741 
  5742 * Provers: improved induct method: assumptions introduced by case
  5743 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5744 the goal statement); "foo" still refers to all facts collectively;
  5745 
  5746 * Provers: the function blast.overloaded has been removed: all constants
  5747 are regarded as potentially overloaded, which improves robustness in exchange
  5748 for slight decrease in efficiency;
  5749 
  5750 * Provers/linorder: New generic prover for transitivity reasoning over
  5751 linear orders.  Note: this prover is not efficient!
  5752 
  5753 * Isar: preview of problems to finish 'show' now produce an error
  5754 rather than just a warning (in interactive mode);
  5755 
  5756 
  5757 *** HOL ***
  5758 
  5759 * arith(_tac)
  5760 
  5761  - Produces a counter example if it cannot prove a goal.
  5762    Note that the counter example may be spurious if the goal is not a formula
  5763    of quantifier-free linear arithmetic.
  5764    In ProofGeneral the counter example appears in the trace buffer.
  5765 
  5766  - Knows about div k and mod k where k is a numeral of type nat or int.
  5767 
  5768  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  5769    linear arithmetic fails. This takes account of quantifiers and divisibility.
  5770    Presburger arithmetic can also be called explicitly via presburger(_tac).
  5771 
  5772 * simp's arithmetic capabilities have been enhanced a bit: it now
  5773 takes ~= in premises into account (by performing a case split);
  5774 
  5775 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  5776 are distributed over a sum of terms;
  5777 
  5778 * New tactic "trans_tac" and method "trans" instantiate
  5779 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  5780 "<=", "<" and "=").
  5781 
  5782 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  5783 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  5784 
  5785 * 'typedef' command has new option "open" to suppress the set
  5786 definition;
  5787 
  5788 * functions Min and Max on finite sets have been introduced (theory
  5789 Finite_Set);
  5790 
  5791 * attribute [symmetric] now works for relations as well; it turns
  5792 (x,y) : R^-1 into (y,x) : R, and vice versa;
  5793 
  5794 * induct over a !!-quantified statement (say !!x1..xn):
  5795   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  5796 
  5797 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  5798 %x. None. Warning: empty_def now refers to the previously hidden definition
  5799 of the empty set.
  5800 
  5801 * Algebra: formalization of classical algebra.  Intended as base for
  5802 any algebraic development in Isabelle.  Currently covers group theory
  5803 (up to Sylow's theorem) and ring theory (Universal Property of
  5804 Univariate Polynomials).  Contributions welcome;
  5805 
  5806 * GroupTheory: deleted, since its material has been moved to Algebra;
  5807 
  5808 * Complex: new directory of the complex numbers with numeric constants,
  5809 nonstandard complex numbers, and some complex analysis, standard and
  5810 nonstandard (Jacques Fleuriot);
  5811 
  5812 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  5813 
  5814 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  5815 Fleuriot);
  5816 
  5817 * Real/HahnBanach: updated and adapted to locales;
  5818 
  5819 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  5820 Gray and Kramer);
  5821 
  5822 * UNITY: added the Meier-Sanders theory of progress sets;
  5823 
  5824 * MicroJava: bytecode verifier and lightweight bytecode verifier
  5825 as abstract algorithms, instantiated to the JVM;
  5826 
  5827 * Bali: Java source language formalization. Type system, operational
  5828 semantics, axiomatic semantics. Supported language features:
  5829 classes, interfaces, objects,virtual methods, static methods,
  5830 static/instance fields, arrays, access modifiers, definite
  5831 assignment, exceptions.
  5832 
  5833 
  5834 *** ZF ***
  5835 
  5836 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  5837 universe, etc.);
  5838 
  5839 * Main ZF: virtually all theories converted to new-style format;
  5840 
  5841 
  5842 *** ML ***
  5843 
  5844 * Pure: Tactic.prove provides sane interface for internal proofs;
  5845 omits the infamous "standard" operation, so this is more appropriate
  5846 than prove_goalw_cterm in many situations (e.g. in simprocs);
  5847 
  5848 * Pure: improved error reporting of simprocs;
  5849 
  5850 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  5851 up simprocs;
  5852 
  5853 
  5854 *** Document preparation ***
  5855 
  5856 * uses \par instead of \\ for line breaks in theory text. This may
  5857 shift some page breaks in large documents. To get the old behaviour
  5858 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  5859 
  5860 * minimized dependencies of isabelle.sty and isabellesym.sty on
  5861 other packages
  5862 
  5863 * \<euro> now needs package babel/greek instead of marvosym (which
  5864 broke \Rightarrow)
  5865 
  5866 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  5867 textcomp package)
  5868 
  5869 
  5870 
  5871 New in Isabelle2002 (March 2002)
  5872 --------------------------------
  5873 
  5874 *** Document preparation ***
  5875 
  5876 * greatly simplified document preparation setup, including more
  5877 graceful interpretation of isatool usedir -i/-d/-D options, and more
  5878 instructive isatool mkdir; users should basically be able to get
  5879 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  5880 users may run a separate document processing stage manually like this:
  5881 "isatool usedir -D output HOL Test && isatool document Test/output";
  5882 
  5883 * theory dependency graph may now be incorporated into documents;
  5884 isatool usedir -g true will produce session_graph.eps/.pdf for use
  5885 with \includegraphics of LaTeX;
  5886 
  5887 * proper spacing of consecutive markup elements, especially text
  5888 blocks after section headings;
  5889 
  5890 * support bold style (for single symbols only), input syntax is like
  5891 this: "\<^bold>\<alpha>" or "\<^bold>A";
  5892 
  5893 * \<bullet> is now output as bold \cdot by default, which looks much
  5894 better in printed text;
  5895 
  5896 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  5897 note that these symbols are currently unavailable in Proof General /
  5898 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  5899 
  5900 * isatool latex no longer depends on changed TEXINPUTS, instead
  5901 isatool document copies the Isabelle style files to the target
  5902 location;
  5903 
  5904 
  5905 *** Isar ***
  5906 
  5907 * Pure/Provers: improved proof by cases and induction;
  5908   - 'case' command admits impromptu naming of parameters (such as
  5909     "case (Suc n)");
  5910   - 'induct' method divinates rule instantiation from the inductive
  5911     claim; no longer requires excessive ?P bindings for proper
  5912     instantiation of cases;
  5913   - 'induct' method properly enumerates all possibilities of set/type
  5914     rules; as a consequence facts may be also passed through *type*
  5915     rules without further ado;
  5916   - 'induct' method now derives symbolic cases from the *rulified*
  5917     rule (before it used to rulify cases stemming from the internal
  5918     atomized version); this means that the context of a non-atomic
  5919     statement becomes is included in the hypothesis, avoiding the
  5920     slightly cumbersome show "PROP ?case" form;
  5921   - 'induct' may now use elim-style induction rules without chaining
  5922     facts, using ``missing'' premises from the goal state; this allows
  5923     rules stemming from inductive sets to be applied in unstructured
  5924     scripts, while still benefitting from proper handling of non-atomic
  5925     statements; NB: major inductive premises need to be put first, all
  5926     the rest of the goal is passed through the induction;
  5927   - 'induct' proper support for mutual induction involving non-atomic
  5928     rule statements (uses the new concept of simultaneous goals, see
  5929     below);
  5930   - append all possible rule selections, but only use the first
  5931     success (no backtracking);
  5932   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  5933   - undeclared rule case names default to numbers 1, 2, 3, ...;
  5934   - added 'print_induct_rules' (covered by help item in recent Proof
  5935     General versions);
  5936   - moved induct/cases attributes to Pure, methods to Provers;
  5937   - generic method setup instantiated for FOL and HOL;
  5938 
  5939 * Pure: support multiple simultaneous goal statements, for example
  5940 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  5941 meta-level mechanism, this acts as if several individual goals had
  5942 been stated separately; in particular common proof methods need to be
  5943 repeated in order to cover all claims; note that a single elimination
  5944 step is *not* sufficient to establish the two conjunctions, so this
  5945 fails:
  5946 
  5947   assume "A & B" then have A and B ..   (*".." fails*)
  5948 
  5949 better use "obtain" in situations as above; alternative refer to
  5950 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  5951 
  5952 * Pure: proper integration with ``locales''; unlike the original
  5953 version by Florian Kammller, Isar locales package high-level proof
  5954 contexts rather than raw logical ones (e.g. we admit to include
  5955 attributes everywhere); operations on locales include merge and
  5956 rename; support for implicit arguments (``structures''); simultaneous
  5957 type-inference over imports and text; see also HOL/ex/Locales.thy for
  5958 some examples;
  5959 
  5960 * Pure: the following commands have been ``localized'', supporting a
  5961 target locale specification "(in name)": 'lemma', 'theorem',
  5962 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  5963 stored both within the locale and at the theory level (exported and
  5964 qualified by the locale name);
  5965 
  5966 * Pure: theory goals may now be specified in ``long'' form, with
  5967 ad-hoc contexts consisting of arbitrary locale elements. for example
  5968 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  5969 definitions may be given, too); the result is a meta-level rule with
  5970 the context elements being discharged in the obvious way;
  5971 
  5972 * Pure: new proof command 'using' allows to augment currently used
  5973 facts after a goal statement ('using' is syntactically analogous to
  5974 'apply', but acts on the goal's facts only); this allows chained facts
  5975 to be separated into parts given before and after a claim, as in
  5976 ``from a and b have C using d and e <proof>'';
  5977 
  5978 * Pure: renamed "antecedent" case to "rule_context";
  5979 
  5980 * Pure: new 'judgment' command records explicit information about the
  5981 object-logic embedding (used by several tools internally); no longer
  5982 use hard-wired "Trueprop";
  5983 
  5984 * Pure: added 'corollary' command;
  5985 
  5986 * Pure: fixed 'token_translation' command;
  5987 
  5988 * Pure: removed obsolete 'exported' attribute;
  5989 
  5990 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  5991 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  5992 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  5993 
  5994 * Pure: method 'atomize' presents local goal premises as object-level
  5995 statements (atomic meta-level propositions); setup controlled via
  5996 rewrite rules declarations of 'atomize' attribute; example
  5997 application: 'induct' method with proper rule statements in improper
  5998 proof *scripts*;
  5999 
  6000 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  6001 now consider the syntactic context of assumptions, giving a better
  6002 chance to get type-inference of the arguments right (this is
  6003 especially important for locales);
  6004 
  6005 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  6006 mode;
  6007 
  6008 * Pure/obtain: the formal conclusion "thesis", being marked as
  6009 ``internal'', may no longer be reference directly in the text;
  6010 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  6011 situations;
  6012 
  6013 * Pure: generic 'sym' attribute which declares a rule both as pure
  6014 'elim?' and for the 'symmetric' operation;
  6015 
  6016 * Pure: marginal comments ``--'' may now occur just anywhere in the
  6017 text; the fixed correlation with particular command syntax has been
  6018 discontinued;
  6019 
  6020 * Pure: new method 'rules' is particularly well-suited for proof
  6021 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  6022 but often produces more compact proof terms with less detours;
  6023 
  6024 * Pure/Provers/classical: simplified integration with pure rule
  6025 attributes and methods; the classical "intro?/elim?/dest?"
  6026 declarations coincide with the pure ones; the "rule" method no longer
  6027 includes classically swapped intros; "intro" and "elim" methods no
  6028 longer pick rules from the context; also got rid of ML declarations
  6029 AddXIs/AddXEs/AddXDs; all of this has some potential for
  6030 INCOMPATIBILITY;
  6031 
  6032 * Provers/classical: attribute 'swapped' produces classical inversions
  6033 of introduction rules;
  6034 
  6035 * Provers/simplifier: 'simplified' attribute may refer to explicit
  6036 rules instead of full simplifier context; 'iff' attribute handles
  6037 conditional rules;
  6038 
  6039 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  6040 
  6041 * HOL: 'recdef' now fails on unfinished automated proofs, use
  6042 "(permissive)" option to recover old behavior;
  6043 
  6044 * HOL: 'inductive' no longer features separate (collective) attributes
  6045 for 'intros' (was found too confusing);
  6046 
  6047 * HOL: properly declared induction rules less_induct and
  6048 wf_induct_rule;
  6049 
  6050 
  6051 *** HOL ***
  6052 
  6053 * HOL: moved over to sane numeral syntax; the new policy is as
  6054 follows:
  6055 
  6056   - 0 and 1 are polymorphic constants, which are defined on any
  6057   numeric type (nat, int, real etc.);
  6058 
  6059   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  6060   binary representation internally;
  6061 
  6062   - type nat has special constructor Suc, and generally prefers Suc 0
  6063   over 1::nat and Suc (Suc 0) over 2::nat;
  6064 
  6065 This change may cause significant problems of INCOMPATIBILITY; here
  6066 are some hints on converting existing sources:
  6067 
  6068   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  6069   entities, so expressions involving "-" (unary or binary minus) need
  6070   to be spaced properly;
  6071 
  6072   - existing occurrences of "1" may need to be constraint "1::nat" or
  6073   even replaced by Suc 0; similar for old "2";
  6074 
  6075   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  6076 
  6077   - remove all special provisions on numerals in proofs;
  6078 
  6079 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  6080 representation (depends on bin_arith_simps in the default context);
  6081 
  6082 * HOL: symbolic syntax for x^2 (numeral 2);
  6083 
  6084 * HOL: the class of all HOL types is now called "type" rather than
  6085 "term"; INCOMPATIBILITY, need to adapt references to this type class
  6086 in axclass/classes, instance/arities, and (usually rare) occurrences
  6087 in typings (of consts etc.); internally the class is called
  6088 "HOL.type", ML programs should refer to HOLogic.typeS;
  6089 
  6090 * HOL/record package improvements:
  6091   - new derived operations "fields" to build a partial record section,
  6092     "extend" to promote a fixed record to a record scheme, and
  6093     "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*
  6094     declared as simp by default;
  6095   - shared operations ("more", "fields", etc.) now need to be always
  6096     qualified) --- potential INCOMPATIBILITY;
  6097   - removed "make_scheme" operations (use "make" with "extend") --
  6098     INCOMPATIBILITY;
  6099   - removed "more" class (simply use "term") -- INCOMPATIBILITY;
  6100   - provides cases/induct rules for use with corresponding Isar
  6101     methods (for concrete records, record schemes, concrete more
  6102     parts, and schematic more parts -- in that order);
  6103   - internal definitions directly based on a light-weight abstract
  6104     theory of product types over typedef rather than datatype;
  6105 
  6106 * HOL: generic code generator for generating executable ML code from
  6107 specifications; specific support for HOL constructs such as inductive
  6108 datatypes and sets, as well as recursive functions; can be invoked
  6109 via 'generate_code' theory section;
  6110 
  6111 * HOL: canonical cases/induct rules for n-tuples (n = 3..7);
  6112 
  6113 * HOL: consolidated and renamed several theories.  In particular:
  6114         Ord.thy has been absorbed into HOL.thy
  6115         String.thy has been absorbed into List.thy
  6116 
  6117 * HOL: concrete setsum syntax "\<Sum>i:A. b" == "setsum (%i. b) A"
  6118 (beware of argument permutation!);
  6119 
  6120 * HOL: linorder_less_split superseded by linorder_cases;
  6121 
  6122 * HOL/List: "nodups" renamed to "distinct";
  6123 
  6124 * HOL: added "The" definite description operator; move Hilbert's "Eps"
  6125 to peripheral theory "Hilbert_Choice"; some INCOMPATIBILITIES:
  6126   - Ex_def has changed, now need to use some_eq_ex
  6127 
  6128 * HOL: made split_all_tac safe; EXISTING PROOFS MAY FAIL OR LOOP, so
  6129 in this (rare) case use:
  6130 
  6131   delSWrapper "split_all_tac"
  6132   addSbefore ("unsafe_split_all_tac", unsafe_split_all_tac)
  6133 
  6134 * HOL: added safe wrapper "split_conv_tac" to claset; EXISTING PROOFS
  6135 MAY FAIL;
  6136 
  6137 * HOL: introduced f^n = f o ... o f; warning: due to the limits of
  6138 Isabelle's type classes, ^ on functions and relations has too general
  6139 a domain, namely ('a * 'b) set and 'a => 'b; this means that it may be
  6140 necessary to attach explicit type constraints;
  6141 
  6142 * HOL/Relation: the prefix name of the infix "O" has been changed from
  6143 "comp" to "rel_comp"; INCOMPATIBILITY: a few theorems have been
  6144 renamed accordingly (eg "compI" -> "rel_compI").
  6145 
  6146 * HOL: syntax translations now work properly with numerals and records
  6147 expressions;
  6148 
  6149 * HOL: bounded abstraction now uses syntax "%" / "\<lambda>" instead
  6150 of "lam" -- INCOMPATIBILITY;
  6151 
  6152 * HOL: got rid of some global declarations (potential INCOMPATIBILITY
  6153 for ML tools): const "()" renamed "Product_Type.Unity", type "unit"
  6154 renamed "Product_Type.unit";
  6155 
  6156 * HOL: renamed rtrancl_into_rtrancl2 to converse_rtrancl_into_rtrancl
  6157 
  6158 * HOL: removed obsolete theorem "optionE" (use "option.exhaust", or
  6159 the "cases" method);
  6160 
  6161 * HOL/GroupTheory: group theory examples including Sylow's theorem (by
  6162 Florian Kammller);
  6163 
  6164 * HOL/IMP: updated and converted to new-style theory format; several
  6165 parts turned into readable document, with proper Isar proof texts and
  6166 some explanations (by Gerwin Klein);
  6167 
  6168 * HOL-Real: added Complex_Numbers (by Gertrud Bauer);
  6169 
  6170 * HOL-Hyperreal is now a logic image;
  6171 
  6172 
  6173 *** HOLCF ***
  6174 
  6175 * Isar: consts/constdefs supports mixfix syntax for continuous
  6176 operations;
  6177 
  6178 * Isar: domain package adapted to new-style theory format, e.g. see
  6179 HOLCF/ex/Dnat.thy;
  6180 
  6181 * theory Lift: proper use of rep_datatype lift instead of ML hacks --
  6182 potential INCOMPATIBILITY; now use plain induct_tac instead of former
  6183 lift.induct_tac, always use UU instead of Undef;
  6184 
  6185 * HOLCF/IMP: updated and converted to new-style theory;
  6186 
  6187 
  6188 *** ZF ***
  6189 
  6190 * Isar: proper integration of logic-specific tools and packages,
  6191 including theory commands '(co)inductive', '(co)datatype',
  6192 'rep_datatype', 'inductive_cases', as well as methods 'ind_cases',
  6193 'induct_tac', 'case_tac', and 'typecheck' (with attribute 'TC');
  6194 
  6195 * theory Main no longer includes AC; for the Axiom of Choice, base
  6196 your theory on Main_ZFC;
  6197 
  6198 * the integer library now covers quotients and remainders, with many
  6199 laws relating division to addition, multiplication, etc.;
  6200 
  6201 * ZF/UNITY: Chandy and Misra's UNITY is now available in ZF, giving a
  6202 typeless version of the formalism;
  6203 
  6204 * ZF/AC, Coind, IMP, Resid: updated and converted to new-style theory
  6205 format;
  6206 
  6207 * ZF/Induct: new directory for examples of inductive definitions,
  6208 including theory Multiset for multiset orderings; converted to
  6209 new-style theory format;
  6210 
  6211 * ZF: many new theorems about lists, ordinals, etc.;
  6212 
  6213 
  6214 *** General ***
  6215 
  6216 * Pure/kernel: meta-level proof terms (by Stefan Berghofer); reference
  6217 variable proof controls level of detail: 0 = no proofs (only oracle
  6218 dependencies), 1 = lemma dependencies, 2 = compact proof terms; see
  6219 also ref manual for further ML interfaces;
  6220 
  6221 * Pure/axclass: removed obsolete ML interface
  6222 goal_subclass/goal_arity;
  6223 
  6224 * Pure/syntax: new token syntax "num" for plain numerals (without "#"
  6225 of "xnum"); potential INCOMPATIBILITY, since -0, -1 etc. are now
  6226 separate tokens, so expressions involving minus need to be spaced
  6227 properly;
  6228 
  6229 * Pure/syntax: support non-oriented infixes, using keyword "infix"
  6230 rather than "infixl" or "infixr";
  6231 
  6232 * Pure/syntax: concrete syntax for dummy type variables admits genuine
  6233 sort constraint specifications in type inference; e.g. "x::_::foo"
  6234 ensures that the type of "x" is of sort "foo" (but not necessarily a
  6235 type variable);
  6236 
  6237 * Pure/syntax: print modes "type_brackets" and "no_type_brackets"
  6238 control output of nested => (types); the default behavior is
  6239 "type_brackets";
  6240 
  6241 * Pure/syntax: builtin parse translation for "_constify" turns valued
  6242 tokens into AST constants;
  6243 
  6244 * Pure/syntax: prefer later declarations of translations and print
  6245 translation functions; potential INCOMPATIBILITY: need to reverse
  6246 multiple declarations for same syntax element constant;
  6247 
  6248 * Pure/show_hyps reset by default (in accordance to existing Isar
  6249 practice);
  6250 
  6251 * Provers/classical: renamed addaltern to addafter, addSaltern to
  6252 addSafter;
  6253 
  6254 * Provers/clasimp: ``iff'' declarations now handle conditional rules
  6255 as well;
  6256 
  6257 * system: tested support for MacOS X; should be able to get Isabelle +
  6258 Proof General to work in a plain Terminal after installing Poly/ML
  6259 (e.g. from the Isabelle distribution area) and GNU bash alone
  6260 (e.g. from http://www.apple.com); full X11, XEmacs and X-Symbol
  6261 support requires further installations, e.g. from
  6262 http://fink.sourceforge.net/);
  6263 
  6264 * system: support Poly/ML 4.1.1 (able to manage larger heaps);
  6265 
  6266 * system: reduced base memory usage by Poly/ML (approx. 20 MB instead
  6267 of 40 MB), cf. ML_OPTIONS;
  6268 
  6269 * system: Proof General keywords specification is now part of the
  6270 Isabelle distribution (see etc/isar-keywords.el);
  6271 
  6272 * system: support for persistent Proof General sessions (refrain from
  6273 outdating all loaded theories on startup); user may create writable
  6274 logic images like this: ``isabelle -q HOL Test'';
  6275 
  6276 * system: smart selection of Isabelle process versus Isabelle
  6277 interface, accommodates case-insensitive file systems (e.g. HFS+); may
  6278 run both "isabelle" and "Isabelle" even if file names are badly
  6279 damaged (executable inspects the case of the first letter of its own
  6280 name); added separate "isabelle-process" and "isabelle-interface";
  6281 
  6282 * system: refrain from any attempt at filtering input streams; no
  6283 longer support ``8bit'' encoding of old isabelle font, instead proper
  6284 iso-latin characters may now be used; the related isatools
  6285 "symbolinput" and "nonascii" have disappeared as well;
  6286 
  6287 * system: removed old "xterm" interface (the print modes "xterm" and
  6288 "xterm_color" are still available for direct use in a suitable
  6289 terminal);
  6290 
  6291 
  6292 
  6293 New in Isabelle99-2 (February 2001)
  6294 -----------------------------------
  6295 
  6296 *** Overview of INCOMPATIBILITIES ***
  6297 
  6298 * HOL: please note that theories in the Library and elsewhere often use the
  6299 new-style (Isar) format; to refer to their theorems in an ML script you must
  6300 bind them to ML identifers by e.g.      val thm_name = thm "thm_name";
  6301 
  6302 * HOL: inductive package no longer splits induction rule aggressively,
  6303 but only as far as specified by the introductions given; the old
  6304 format may be recovered via ML function complete_split_rule or attribute
  6305 'split_rule (complete)';
  6306 
  6307 * HOL: induct renamed to lfp_induct, lfp_Tarski to lfp_unfold,
  6308 gfp_Tarski to gfp_unfold;
  6309 
  6310 * HOL: contrapos, contrapos2 renamed to contrapos_nn, contrapos_pp;
  6311 
  6312 * HOL: infix "dvd" now has priority 50 rather than 70 (because it is a
  6313 relation); infix "^^" has been renamed "``"; infix "``" has been
  6314 renamed "`"; "univalent" has been renamed "single_valued";
  6315 
  6316 * HOL/Real: "rinv" and "hrinv" replaced by overloaded "inverse"
  6317 operation;
  6318 
  6319 * HOLCF: infix "`" has been renamed "$"; the symbol syntax is \<cdot>;
  6320 
  6321 * Isar: 'obtain' no longer declares "that" fact as simp/intro;
  6322 
  6323 * Isar/HOL: method 'induct' now handles non-atomic goals; as a
  6324 consequence, it is no longer monotonic wrt. the local goal context
  6325 (which is now passed through the inductive cases);
  6326 
  6327 * Document preparation: renamed standard symbols \<ll> to \<lless> and
  6328 \<gg> to \<ggreater>;
  6329 
  6330 
  6331 *** Document preparation ***
  6332 
  6333 * \isabellestyle{NAME} selects version of Isabelle output (currently
  6334 available: are "it" for near math-mode best-style output, "sl" for
  6335 slanted text style, and "tt" for plain type-writer; if no
  6336 \isabellestyle command is given, output is according to slanted
  6337 type-writer);
  6338 
  6339 * support sub/super scripts (for single symbols only), input syntax is
  6340 like this: "A\<^sup>*" or "A\<^sup>\<star>";
  6341 
  6342 * some more standard symbols; see Appendix A of the system manual for
  6343 the complete list of symbols defined in isabellesym.sty;
  6344 
  6345 * improved isabelle style files; more abstract symbol implementation
  6346 (should now use \isamath{...} and \isatext{...} in custom symbol
  6347 definitions);
  6348 
  6349 * antiquotation @{goals} and @{subgoals} for output of *dynamic* goals
  6350 state; Note that presentation of goal states does not conform to
  6351 actual human-readable proof documents.  Please do not include goal
  6352 states into document output unless you really know what you are doing!
  6353 
  6354 * proper indentation of antiquoted output with proportional LaTeX
  6355 fonts;
  6356 
  6357 * no_document ML operator temporarily disables LaTeX document
  6358 generation;
  6359 
  6360 * isatool unsymbolize tunes sources for plain ASCII communication;
  6361 
  6362 
  6363 *** Isar ***
  6364 
  6365 * Pure: Isar now suffers initial goal statements to contain unbound
  6366 schematic variables (this does not conform to actual readable proof
  6367 documents, due to unpredictable outcome and non-compositional proof
  6368 checking); users who know what they are doing may use schematic goals
  6369 for Prolog-style synthesis of proven results;
  6370 
  6371 * Pure: assumption method (an implicit finishing) now handles actual
  6372 rules as well;
  6373 
  6374 * Pure: improved 'obtain' --- moved to Pure, insert "that" into
  6375 initial goal, declare "that" only as Pure intro (only for single
  6376 steps); the "that" rule assumption may now be involved in implicit
  6377 finishing, thus ".." becomes a feasible for trivial obtains;
  6378 
  6379 * Pure: default proof step now includes 'intro_classes'; thus trivial
  6380 instance proofs may be performed by "..";
  6381 
  6382 * Pure: ?thesis / ?this / "..." now work for pure meta-level
  6383 statements as well;
  6384 
  6385 * Pure: more robust selection of calculational rules;
  6386 
  6387 * Pure: the builtin notion of 'finished' goal now includes the ==-refl
  6388 rule (as well as the assumption rule);
  6389 
  6390 * Pure: 'thm_deps' command visualizes dependencies of theorems and
  6391 lemmas, using the graph browser tool;
  6392 
  6393 * Pure: predict failure of "show" in interactive mode;
  6394 
  6395 * Pure: 'thms_containing' now takes actual terms as arguments;
  6396 
  6397 * HOL: improved method 'induct' --- now handles non-atomic goals
  6398 (potential INCOMPATIBILITY); tuned error handling;
  6399 
  6400 * HOL: cases and induct rules now provide explicit hints about the
  6401 number of facts to be consumed (0 for "type" and 1 for "set" rules);
  6402 any remaining facts are inserted into the goal verbatim;
  6403 
  6404 * HOL: local contexts (aka cases) may now contain term bindings as
  6405 well; the 'cases' and 'induct' methods new provide a ?case binding for
  6406 the result to be shown in each case;
  6407 
  6408 * HOL: added 'recdef_tc' command;
  6409 
  6410 * isatool convert assists in eliminating legacy ML scripts;
  6411 
  6412 
  6413 *** HOL ***
  6414 
  6415 * HOL/Library: a collection of generic theories to be used together
  6416 with main HOL; the theory loader path already includes this directory
  6417 by default; the following existing theories have been moved here:
  6418 HOL/Induct/Multiset, HOL/Induct/Acc (as Accessible_Part), HOL/While
  6419 (as While_Combinator), HOL/Lex/Prefix (as List_Prefix);
  6420 
  6421 * HOL/Unix: "Some aspects of Unix file-system security", a typical
  6422 modelling and verification task performed in Isabelle/HOL +
  6423 Isabelle/Isar + Isabelle document preparation (by Markus Wenzel).
  6424 
  6425 * HOL/Algebra: special summation operator SUM no longer exists, it has
  6426 been replaced by setsum; infix 'assoc' now has priority 50 (like
  6427 'dvd'); axiom 'one_not_zero' has been moved from axclass 'ring' to
  6428 'domain', this makes the theory consistent with mathematical
  6429 literature;
  6430 
  6431 * HOL basics: added overloaded operations "inverse" and "divide"
  6432 (infix "/"), syntax for generic "abs" operation, generic summation
  6433 operator \<Sum>;
  6434 
  6435 * HOL/typedef: simplified package, provide more useful rules (see also
  6436 HOL/subset.thy);
  6437 
  6438 * HOL/datatype: induction rule for arbitrarily branching datatypes is
  6439 now expressed as a proper nested rule (old-style tactic scripts may
  6440 require atomize_strip_tac to cope with non-atomic premises);
  6441 
  6442 * HOL: renamed theory "Prod" to "Product_Type", renamed "split" rule
  6443 to "split_conv" (old name still available for compatibility);
  6444 
  6445 * HOL: improved concrete syntax for strings (e.g. allows translation
  6446 rules with string literals);
  6447 
  6448 * HOL-Real-Hyperreal: this extends HOL-Real with the hyperreals
  6449  and Fleuriot's mechanization of analysis, including the transcendental
  6450  functions for the reals;
  6451 
  6452 * HOL/Real, HOL/Hyperreal: improved arithmetic simplification;
  6453 
  6454 
  6455 *** CTT ***
  6456 
  6457 * CTT: x-symbol support for Pi, Sigma, -->, : (membership); note that
  6458 "lam" is displayed as TWO lambda-symbols
  6459 
  6460 * CTT: theory Main now available, containing everything (that is, Bool
  6461 and Arith);
  6462 
  6463 
  6464 *** General ***
  6465 
  6466 * Pure: the Simplifier has been implemented properly as a derived rule
  6467 outside of the actual kernel (at last!); the overall performance
  6468 penalty in practical applications is about 50%, while reliability of
  6469 the Isabelle inference kernel has been greatly improved;
  6470 
  6471 * print modes "brackets" and "no_brackets" control output of nested =>
  6472 (types) and ==> (props); the default behaviour is "brackets";
  6473 
  6474 * Provers: fast_tac (and friends) now handle actual object-logic rules
  6475 as assumptions as well;
  6476 
  6477 * system: support Poly/ML 4.0;
  6478 
  6479 * system: isatool install handles KDE version 1 or 2;
  6480 
  6481 
  6482 
  6483 New in Isabelle99-1 (October 2000)
  6484 ----------------------------------
  6485 
  6486 *** Overview of INCOMPATIBILITIES ***
  6487 
  6488 * HOL: simplification of natural numbers is much changed; to partly
  6489 recover the old behaviour (e.g. to prevent n+n rewriting to #2*n)
  6490 issue the following ML commands:
  6491 
  6492   Delsimprocs Nat_Numeral_Simprocs.cancel_numerals;
  6493   Delsimprocs [Nat_Numeral_Simprocs.combine_numerals];
  6494 
  6495 * HOL: simplification no longer dives into case-expressions; this is
  6496 controlled by "t.weak_case_cong" for each datatype t;
  6497 
  6498 * HOL: nat_less_induct renamed to less_induct;
  6499 
  6500 * HOL: systematic renaming of the SOME (Eps) rules, may use isatool
  6501 fixsome to patch .thy and .ML sources automatically;
  6502 
  6503   select_equality  -> some_equality
  6504   select_eq_Ex     -> some_eq_ex
  6505   selectI2EX       -> someI2_ex
  6506   selectI2         -> someI2
  6507   selectI          -> someI
  6508   select1_equality -> some1_equality
  6509   Eps_sym_eq       -> some_sym_eq_trivial
  6510   Eps_eq           -> some_eq_trivial
  6511 
  6512 * HOL: exhaust_tac on datatypes superceded by new generic case_tac;
  6513 
  6514 * HOL: removed obsolete theorem binding expand_if (refer to split_if
  6515 instead);
  6516 
  6517 * HOL: the recursion equations generated by 'recdef' are now called
  6518 f.simps instead of f.rules;
  6519 
  6520 * HOL: qed_spec_mp now also handles bounded ALL as well;
  6521 
  6522 * HOL: 0 is now overloaded, so the type constraint ":: nat" may
  6523 sometimes be needed;
  6524 
  6525 * HOL: the constant for "f``x" is now "image" rather than "op ``";
  6526 
  6527 * HOL: the constant for "f-``x" is now "vimage" rather than "op -``";
  6528 
  6529 * HOL: the disjoint sum is now "<+>" instead of "Plus"; the cartesian
  6530 product is now "<*>" instead of "Times"; the lexicographic product is
  6531 now "<*lex*>" instead of "**";
  6532 
  6533 * HOL: theory Sexp is now in HOL/Induct examples (it used to be part
  6534 of main HOL, but was unused); better use HOL's datatype package;
  6535 
  6536 * HOL: removed "symbols" syntax for constant "override" of theory Map;
  6537 the old syntax may be recovered as follows:
  6538 
  6539   syntax (symbols)
  6540     override  :: "('a ~=> 'b) => ('a ~=> 'b) => ('a ~=> 'b)"
  6541       (infixl "\\<oplus>" 100)
  6542 
  6543 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  6544 
  6545 * HOL/ML: even fewer consts are declared as global (see theories Ord,
  6546 Lfp, Gfp, WF); this only affects ML packages that refer to const names
  6547 internally;
  6548 
  6549 * HOL and ZF: syntax for quotienting wrt an equivalence relation
  6550 changed from A/r to A//r;
  6551 
  6552 * ZF: new treatment of arithmetic (nat & int) may break some old
  6553 proofs;
  6554 
  6555 * Isar: renamed some attributes (RS -> THEN, simplify -> simplified,
  6556 rulify -> rule_format, elimify -> elim_format, ...);
  6557 
  6558 * Isar/Provers: intro/elim/dest attributes changed; renamed
  6559 intro/intro!/intro!! flags to intro!/intro/intro? (in most cases, one
  6560 should have to change intro!! to intro? only); replaced "delrule" by
  6561 "rule del";
  6562 
  6563 * Isar/HOL: renamed "intrs" to "intros" in inductive definitions;
  6564 
  6565 * Provers: strengthened force_tac by using new first_best_tac;
  6566 
  6567 * LaTeX document preparation: several changes of isabelle.sty (see
  6568 lib/texinputs);
  6569 
  6570 
  6571 *** Document preparation ***
  6572 
  6573 * formal comments (text blocks etc.) in new-style theories may now
  6574 contain antiquotations of thm/prop/term/typ/text to be presented
  6575 according to latex print mode; concrete syntax is like this:
  6576 @{term[show_types] "f(x) = a + x"};
  6577 
  6578 * isatool mkdir provides easy setup of Isabelle session directories,
  6579 including proper document sources;
  6580 
  6581 * generated LaTeX sources are now deleted after successful run
  6582 (isatool document -c); may retain a copy somewhere else via -D option
  6583 of isatool usedir;
  6584 
  6585 * isatool usedir -D now lets isatool latex -o sty update the Isabelle
  6586 style files, achieving self-contained LaTeX sources and simplifying
  6587 LaTeX debugging;
  6588 
  6589 * old-style theories now produce (crude) LaTeX output as well;
  6590 
  6591 * browser info session directories are now self-contained (may be put
  6592 on WWW server seperately); improved graphs of nested sessions; removed
  6593 graph for 'all sessions';
  6594 
  6595 * several improvements in isabelle style files; \isabellestyle{it}
  6596 produces fake math mode output; \isamarkupheader is now \section by
  6597 default; see lib/texinputs/isabelle.sty etc.;
  6598 
  6599 
  6600 *** Isar ***
  6601 
  6602 * Isar/Pure: local results and corresponding term bindings are now
  6603 subject to Hindley-Milner polymorphism (similar to ML); this
  6604 accommodates incremental type-inference very nicely;
  6605 
  6606 * Isar/Pure: new derived language element 'obtain' supports
  6607 generalized existence reasoning;
  6608 
  6609 * Isar/Pure: new calculational elements 'moreover' and 'ultimately'
  6610 support accumulation of results, without applying any rules yet;
  6611 useful to collect intermediate results without explicit name
  6612 references, and for use with transitivity rules with more than 2
  6613 premises;
  6614 
  6615 * Isar/Pure: scalable support for case-analysis type proofs: new
  6616 'case' language element refers to local contexts symbolically, as
  6617 produced by certain proof methods; internally, case names are attached
  6618 to theorems as "tags";
  6619 
  6620 * Isar/Pure: theory command 'hide' removes declarations from
  6621 class/type/const name spaces;
  6622 
  6623 * Isar/Pure: theory command 'defs' supports option "(overloaded)" to
  6624 indicate potential overloading;
  6625 
  6626 * Isar/Pure: changed syntax of local blocks from {{ }} to { };
  6627 
  6628 * Isar/Pure: syntax of sorts made 'inner', i.e. have to write
  6629 "{a,b,c}" instead of {a,b,c};
  6630 
  6631 * Isar/Pure now provides its own version of intro/elim/dest
  6632 attributes; useful for building new logics, but beware of confusion
  6633 with the version in Provers/classical;
  6634 
  6635 * Isar/Pure: the local context of (non-atomic) goals is provided via
  6636 case name 'antecedent';
  6637 
  6638 * Isar/Pure: removed obsolete 'transfer' attribute (transfer of thms
  6639 to the current context is now done automatically);
  6640 
  6641 * Isar/Pure: theory command 'method_setup' provides a simple interface
  6642 for definining proof methods in ML;
  6643 
  6644 * Isar/Provers: intro/elim/dest attributes changed; renamed
  6645 intro/intro!/intro!! flags to intro!/intro/intro? (INCOMPATIBILITY, in
  6646 most cases, one should have to change intro!! to intro? only);
  6647 replaced "delrule" by "rule del";
  6648 
  6649 * Isar/Provers: new 'hypsubst' method, plain 'subst' method and
  6650 'symmetric' attribute (the latter supercedes [RS sym]);
  6651 
  6652 * Isar/Provers: splitter support (via 'split' attribute and 'simp'
  6653 method modifier); 'simp' method: 'only:' modifier removes loopers as
  6654 well (including splits);
  6655 
  6656 * Isar/Provers: Simplifier and Classical methods now support all kind
  6657 of modifiers used in the past, including 'cong', 'iff', etc.
  6658 
  6659 * Isar/Provers: added 'fastsimp' and 'clarsimp' methods (combination
  6660 of Simplifier and Classical reasoner);
  6661 
  6662 * Isar/HOL: new proof method 'cases' and improved version of 'induct'
  6663 now support named cases; major packages (inductive, datatype, primrec,
  6664 recdef) support case names and properly name parameters;
  6665 
  6666 * Isar/HOL: new transitivity rules for substitution in inequalities --
  6667 monotonicity conditions are extracted to be proven at end of
  6668 calculations;
  6669 
  6670 * Isar/HOL: removed 'case_split' thm binding, should use 'cases' proof
  6671 method anyway;
  6672 
  6673 * Isar/HOL: removed old expand_if = split_if; theorems if_splits =
  6674 split_if split_if_asm; datatype package provides theorems foo.splits =
  6675 foo.split foo.split_asm for each datatype;
  6676 
  6677 * Isar/HOL: tuned inductive package, rename "intrs" to "intros"
  6678 (potential INCOMPATIBILITY), emulation of mk_cases feature for proof
  6679 scripts: new 'inductive_cases' command and 'ind_cases' method; (Note:
  6680 use "(cases (simplified))" method in proper proof texts);
  6681 
  6682 * Isar/HOL: added global 'arith_split' attribute for 'arith' method;
  6683 
  6684 * Isar: names of theorems etc. may be natural numbers as well;
  6685 
  6686 * Isar: 'pr' command: optional arguments for goals_limit and
  6687 ProofContext.prems_limit; no longer prints theory contexts, but only
  6688 proof states;
  6689 
  6690 * Isar: diagnostic commands 'pr', 'thm', 'prop', 'term', 'typ' admit
  6691 additional print modes to be specified; e.g. "pr(latex)" will print
  6692 proof state according to the Isabelle LaTeX style;
  6693 
  6694 * Isar: improved support for emulating tactic scripts, including proof
  6695 methods 'rule_tac' etc., 'cut_tac', 'thin_tac', 'subgoal_tac',
  6696 'rename_tac', 'rotate_tac', 'tactic', and 'case_tac' / 'induct_tac'
  6697 (for HOL datatypes);
  6698 
  6699 * Isar: simplified (more robust) goal selection of proof methods: 1st
  6700 goal, all goals, or explicit goal specifier (tactic emulation); thus
  6701 'proof method scripts' have to be in depth-first order;
  6702 
  6703 * Isar: tuned 'let' syntax: replaced 'as' keyword by 'and';
  6704 
  6705 * Isar: removed 'help' command, which hasn't been too helpful anyway;
  6706 should instead use individual commands for printing items
  6707 (print_commands, print_methods etc.);
  6708 
  6709 * Isar: added 'nothing' --- the empty list of theorems;
  6710 
  6711 
  6712 *** HOL ***
  6713 
  6714 * HOL/MicroJava: formalization of a fragment of Java, together with a
  6715 corresponding virtual machine and a specification of its bytecode
  6716 verifier and a lightweight bytecode verifier, including proofs of
  6717 type-safety; by Gerwin Klein, Tobias Nipkow, David von Oheimb, and
  6718 Cornelia Pusch (see also the homepage of project Bali at
  6719 http://isabelle.in.tum.de/Bali/);
  6720 
  6721 * HOL/Algebra: new theory of rings and univariate polynomials, by
  6722 Clemens Ballarin;
  6723 
  6724 * HOL/NumberTheory: fundamental Theorem of Arithmetic, Chinese
  6725 Remainder Theorem, Fermat/Euler Theorem, Wilson's Theorem, by Thomas M
  6726 Rasmussen;
  6727 
  6728 * HOL/Lattice: fundamental concepts of lattice theory and order
  6729 structures, including duals, properties of bounds versus algebraic
  6730 laws, lattice operations versus set-theoretic ones, the Knaster-Tarski
  6731 Theorem for complete lattices etc.; may also serve as a demonstration
  6732 for abstract algebraic reasoning using axiomatic type classes, and
  6733 mathematics-style proof in Isabelle/Isar; by Markus Wenzel;
  6734 
  6735 * HOL/Prolog: a (bare-bones) implementation of Lambda-Prolog, by David
  6736 von Oheimb;
  6737 
  6738 * HOL/IMPP: extension of IMP with local variables and mutually
  6739 recursive procedures, by David von Oheimb;
  6740 
  6741 * HOL/Lambda: converted into new-style theory and document;
  6742 
  6743 * HOL/ex/Multiquote: example of multiple nested quotations and
  6744 anti-quotations -- basically a generalized version of de-Bruijn
  6745 representation; very useful in avoiding lifting of operations;
  6746 
  6747 * HOL/record: added general record equality rule to simpset; fixed
  6748 select-update simplification procedure to handle extended records as
  6749 well; admit "r" as field name;
  6750 
  6751 * HOL: 0 is now overloaded over the new sort "zero", allowing its use with
  6752 other numeric types and also as the identity of groups, rings, etc.;
  6753 
  6754 * HOL: new axclass plus_ac0 for addition with the AC-laws and 0 as identity.
  6755 Types nat and int belong to this axclass;
  6756 
  6757 * HOL: greatly improved simplification involving numerals of type nat, int, real:
  6758    (i + #8 + j) = Suc k simplifies to  #7 + (i + j) = k
  6759    i*j + k + j*#3*i     simplifies to  #4*(i*j) + k
  6760   two terms #m*u and #n*u are replaced by #(m+n)*u
  6761     (where #m, #n and u can implicitly be 1; this is simproc combine_numerals)
  6762   and the term/formula #m*u+x ~~ #n*u+y simplifies simplifies to #(m-n)+x ~~ y
  6763     or x ~~ #(n-m)+y, where ~~ is one of = < <= or - (simproc cancel_numerals);
  6764 
  6765 * HOL: meson_tac is available (previously in ex/meson.ML); it is a
  6766 powerful prover for predicate logic but knows nothing of clasets; see
  6767 ex/mesontest.ML and ex/mesontest2.ML for example applications;
  6768 
  6769 * HOL: new version of "case_tac" subsumes both boolean case split and
  6770 "exhaust_tac" on datatypes; INCOMPATIBILITY: exhaust_tac no longer
  6771 exists, may define val exhaust_tac = case_tac for ad-hoc portability;
  6772 
  6773 * HOL: simplification no longer dives into case-expressions: only the
  6774 selector expression is simplified, but not the remaining arms; to
  6775 enable full simplification of case-expressions for datatype t, you may
  6776 remove t.weak_case_cong from the simpset, either globally (Delcongs
  6777 [thm"t.weak_case_cong"];) or locally (delcongs [...]).
  6778 
  6779 * HOL/recdef: the recursion equations generated by 'recdef' for
  6780 function 'f' are now called f.simps instead of f.rules; if all
  6781 termination conditions are proved automatically, these simplification
  6782 rules are added to the simpset, as in primrec; rules may be named
  6783 individually as well, resulting in a separate list of theorems for
  6784 each equation;
  6785 
  6786 * HOL/While is a new theory that provides a while-combinator. It
  6787 permits the definition of tail-recursive functions without the
  6788 provision of a termination measure. The latter is necessary once the
  6789 invariant proof rule for while is applied.
  6790 
  6791 * HOL: new (overloaded) notation for the set of elements below/above
  6792 some element: {..u}, {..u(}, {l..}, {)l..}. See theory SetInterval.
  6793 
  6794 * HOL: theorems impI, allI, ballI bound as "strip";
  6795 
  6796 * HOL: new tactic induct_thm_tac: thm -> string -> int -> tactic
  6797 induct_tac th "x1 ... xn" expects th to have a conclusion of the form
  6798 P v1 ... vn and abbreviates res_inst_tac [("v1","x1"),...,("vn","xn")] th;
  6799 
  6800 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  6801 
  6802 * HOL: theory Sexp now in HOL/Induct examples (it used to be part of
  6803 main HOL, but was unused);
  6804 
  6805 * HOL: fewer consts declared as global (e.g. have to refer to
  6806 "Lfp.lfp" instead of "lfp" internally; affects ML packages only);
  6807 
  6808 * HOL: tuned AST representation of nested pairs, avoiding bogus output
  6809 in case of overlap with user translations (e.g. judgements over
  6810 tuples); (note that the underlying logical represenation is still
  6811 bogus);
  6812 
  6813 
  6814 *** ZF ***
  6815 
  6816 * ZF: simplification automatically cancels common terms in arithmetic
  6817 expressions over nat and int;
  6818 
  6819 * ZF: new treatment of nat to minimize type-checking: all operators
  6820 coerce their operands to a natural number using the function natify,
  6821 making the algebraic laws unconditional;
  6822 
  6823 * ZF: as above, for int: operators coerce their operands to an integer
  6824 using the function intify;
  6825 
  6826 * ZF: the integer library now contains many of the usual laws for the
  6827 orderings, including $<=, and monotonicity laws for $+ and $*;
  6828 
  6829 * ZF: new example ZF/ex/NatSum to demonstrate integer arithmetic
  6830 simplification;
  6831 
  6832 * FOL and ZF: AddIffs now available, giving theorems of the form P<->Q
  6833 to the simplifier and classical reasoner simultaneously;
  6834 
  6835 
  6836 *** General ***
  6837 
  6838 * Provers: blast_tac now handles actual object-logic rules as
  6839 assumptions; note that auto_tac uses blast_tac internally as well;
  6840 
  6841 * Provers: new functions rulify/rulify_no_asm: thm -> thm for turning
  6842 outer -->/All/Ball into ==>/!!; qed_spec_mp now uses rulify_no_asm;
  6843 
  6844 * Provers: delrules now handles destruct rules as well (no longer need
  6845 explicit make_elim);
  6846 
  6847 * Provers: Blast_tac now warns of and ignores "weak elimination rules" e.g.
  6848   [| inj ?f;          ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
  6849 use instead the strong form,
  6850   [| inj ?f; ~ ?W ==> ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
  6851 in HOL, FOL and ZF the function cla_make_elim will create such rules
  6852 from destruct-rules;
  6853 
  6854 * Provers: Simplifier.easy_setup provides a fast path to basic
  6855 Simplifier setup for new object-logics;
  6856 
  6857 * Pure: AST translation rules no longer require constant head on LHS;
  6858 
  6859 * Pure: improved name spaces: ambiguous output is qualified; support
  6860 for hiding of names;
  6861 
  6862 * system: smart setup of canonical ML_HOME, ISABELLE_INTERFACE, and
  6863 XSYMBOL_HOME; no longer need to do manual configuration in most
  6864 situations;
  6865 
  6866 * system: compression of ML heaps images may now be controlled via -c
  6867 option of isabelle and isatool usedir (currently only observed by
  6868 Poly/ML);
  6869 
  6870 * system: isatool installfonts may handle X-Symbol fonts as well (very
  6871 useful for remote X11);
  6872 
  6873 * system: provide TAGS file for Isabelle sources;
  6874 
  6875 * ML: infix 'OF' is a version of 'MRS' with more appropriate argument
  6876 order;
  6877 
  6878 * ML: renamed flags Syntax.trace_norm_ast to Syntax.trace_ast; global
  6879 timing flag supersedes proof_timing and Toplevel.trace;
  6880 
  6881 * ML: new combinators |>> and |>>> for incremental transformations
  6882 with secondary results (e.g. certain theory extensions):
  6883 
  6884 * ML: PureThy.add_defs gets additional argument to indicate potential
  6885 overloading (usually false);
  6886 
  6887 * ML: PureThy.add_thms/add_axioms/add_defs now return theorems as
  6888 results;
  6889 
  6890 
  6891 
  6892 New in Isabelle99 (October 1999)
  6893 --------------------------------
  6894 
  6895 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  6896 
  6897 * HOL: The THEN and ELSE parts of conditional expressions (if P then x else y)
  6898 are no longer simplified.  (This allows the simplifier to unfold recursive
  6899 functional programs.)  To restore the old behaviour, declare
  6900 
  6901     Delcongs [if_weak_cong];
  6902 
  6903 * HOL: Removed the obsolete syntax "Compl A"; use -A for set
  6904 complement;
  6905 
  6906 * HOL: the predicate "inj" is now defined by translation to "inj_on";
  6907 
  6908 * HOL/datatype: mutual_induct_tac no longer exists --
  6909   use induct_tac "x_1 ... x_n" instead of mutual_induct_tac ["x_1", ..., "x_n"]
  6910 
  6911 * HOL/typedef: fixed type inference for representing set; type
  6912 arguments now have to occur explicitly on the rhs as type constraints;
  6913 
  6914 * ZF: The con_defs part of an inductive definition may no longer refer
  6915 to constants declared in the same theory;
  6916 
  6917 * HOL, ZF: the function mk_cases, generated by the inductive
  6918 definition package, has lost an argument.  To simplify its result, it
  6919 uses the default simpset instead of a supplied list of theorems.
  6920 
  6921 * HOL/List: the constructors of type list are now Nil and Cons;
  6922 
  6923 * Simplifier: the type of the infix ML functions
  6924         setSSolver addSSolver setSolver addSolver
  6925 is now  simpset * solver -> simpset  where `solver' is a new abstract type
  6926 for packaging solvers. A solver is created via
  6927         mk_solver: string -> (thm list -> int -> tactic) -> solver
  6928 where the string argument is only a comment.
  6929 
  6930 
  6931 *** Proof tools ***
  6932 
  6933 * Provers/Arith/fast_lin_arith.ML contains a functor for creating a
  6934 decision procedure for linear arithmetic. Currently it is used for
  6935 types `nat', `int', and `real' in HOL (see below); it can, should and
  6936 will be instantiated for other types and logics as well.
  6937 
  6938 * The simplifier now accepts rewrite rules with flexible heads, eg
  6939      hom ?f ==> ?f(?x+?y) = ?f ?x + ?f ?y
  6940   They are applied like any rule with a non-pattern lhs, i.e. by first-order
  6941   matching.
  6942 
  6943 
  6944 *** General ***
  6945 
  6946 * New Isabelle/Isar subsystem provides an alternative to traditional
  6947 tactical theorem proving; together with the ProofGeneral/isar user
  6948 interface it offers an interactive environment for developing human
  6949 readable proof documents (Isar == Intelligible semi-automated
  6950 reasoning); for further information see isatool doc isar-ref,
  6951 src/HOL/Isar_examples and http://isabelle.in.tum.de/Isar/
  6952 
  6953 * improved and simplified presentation of theories: better HTML markup
  6954 (including colors), graph views in several sizes; isatool usedir now
  6955 provides a proper interface for user theories (via -P option); actual
  6956 document preparation based on (PDF)LaTeX is available as well (for
  6957 new-style theories only); see isatool doc system for more information;
  6958 
  6959 * native support for Proof General, both for classic Isabelle and
  6960 Isabelle/Isar;
  6961 
  6962 * ML function thm_deps visualizes dependencies of theorems and lemmas,
  6963 using the graph browser tool;
  6964 
  6965 * Isabelle manuals now also available as PDF;
  6966 
  6967 * theory loader rewritten from scratch (may not be fully
  6968 bug-compatible); old loadpath variable has been replaced by show_path,
  6969 add_path, del_path, reset_path functions; new operations such as
  6970 update_thy, touch_thy, remove_thy, use/update_thy_only (see also
  6971 isatool doc ref);
  6972 
  6973 * improved isatool install: option -k creates KDE application icon,
  6974 option -p DIR installs standalone binaries;
  6975 
  6976 * added ML_PLATFORM setting (useful for cross-platform installations);
  6977 more robust handling of platform specific ML images for SML/NJ;
  6978 
  6979 * the settings environment is now statically scoped, i.e. it is never
  6980 created again in sub-processes invoked from isabelle, isatool, or
  6981 Isabelle;
  6982 
  6983 * path element specification '~~' refers to '$ISABELLE_HOME';
  6984 
  6985 * in locales, the "assumes" and "defines" parts may be omitted if
  6986 empty;
  6987 
  6988 * new print_mode "xsymbols" for extended symbol support (e.g. genuine
  6989 long arrows);
  6990 
  6991 * new print_mode "HTML";
  6992 
  6993 * new flag show_tags controls display of tags of theorems (which are
  6994 basically just comments that may be attached by some tools);
  6995 
  6996 * Isamode 2.6 requires patch to accomodate change of Isabelle font
  6997 mode and goal output format:
  6998 
  6999 diff -r Isamode-2.6/elisp/isa-load.el Isamode/elisp/isa-load.el
  7000 244c244
  7001 <       (list (isa-getenv "ISABELLE") "-msymbols" logic-name)
  7002 ---
  7003 >       (list (isa-getenv "ISABELLE") "-misabelle_font" "-msymbols" logic-name)
  7004 diff -r Isabelle-2.6/elisp/isa-proofstate.el Isamode/elisp/isa-proofstate.el
  7005 181c181
  7006 < (defconst proofstate-proofstart-regexp "^Level [0-9]+$"
  7007 ---
  7008 > (defconst proofstate-proofstart-regexp "^Level [0-9]+"
  7009 
  7010 * function bind_thms stores lists of theorems (cf. bind_thm);
  7011 
  7012 * new shorthand tactics ftac, eatac, datac, fatac;
  7013 
  7014 * qed (and friends) now accept "" as result name; in that case the
  7015 theorem is not stored, but proper checks and presentation of the
  7016 result still apply;
  7017 
  7018 * theorem database now also indexes constants "Trueprop", "all",
  7019 "==>", "=="; thus thms_containing, findI etc. may retrieve more rules;
  7020 
  7021 
  7022 *** HOL ***
  7023 
  7024 ** HOL arithmetic **
  7025 
  7026 * There are now decision procedures for linear arithmetic over nat and
  7027 int:
  7028 
  7029 1. arith_tac copes with arbitrary formulae involving `=', `<', `<=',
  7030 `+', `-', `Suc', `min', `max' and numerical constants; other subterms
  7031 are treated as atomic; subformulae not involving type `nat' or `int'
  7032 are ignored; quantified subformulae are ignored unless they are
  7033 positive universal or negative existential. The tactic has to be
  7034 invoked by hand and can be a little bit slow. In particular, the
  7035 running time is exponential in the number of occurrences of `min' and
  7036 `max', and `-' on `nat'.
  7037 
  7038 2. fast_arith_tac is a cut-down version of arith_tac: it only takes
  7039 (negated) (in)equalities among the premises and the conclusion into
  7040 account (i.e. no compound formulae) and does not know about `min' and
  7041 `max', and `-' on `nat'. It is fast and is used automatically by the
  7042 simplifier.
  7043 
  7044 NB: At the moment, these decision procedures do not cope with mixed
  7045 nat/int formulae where the two parts interact, such as `m < n ==>
  7046 int(m) < int(n)'.
  7047 
  7048 * HOL/Numeral provides a generic theory of numerals (encoded
  7049 efficiently as bit strings); setup for types nat/int/real is in place;
  7050 INCOMPATIBILITY: since numeral syntax is now polymorphic, rather than
  7051 int, existing theories and proof scripts may require a few additional
  7052 type constraints;
  7053 
  7054 * integer division and remainder can now be performed on constant
  7055 arguments;
  7056 
  7057 * many properties of integer multiplication, division and remainder
  7058 are now available;
  7059 
  7060 * An interface to the Stanford Validity Checker (SVC) is available through the
  7061 tactic svc_tac.  Propositional tautologies and theorems of linear arithmetic
  7062 are proved automatically.  SVC must be installed separately, and its results
  7063 must be TAKEN ON TRUST (Isabelle does not check the proofs, but tags any
  7064 invocation of the underlying oracle).  For SVC see
  7065   http://verify.stanford.edu/SVC
  7066 
  7067 * IsaMakefile: the HOL-Real target now builds an actual image;
  7068 
  7069 
  7070 ** HOL misc **
  7071 
  7072 * HOL/Real/HahnBanach: the Hahn-Banach theorem for real vector spaces
  7073 (in Isabelle/Isar) -- by Gertrud Bauer;
  7074 
  7075 * HOL/BCV: generic model of bytecode verification, i.e. data-flow
  7076 analysis for assembly languages with subtypes;
  7077 
  7078 * HOL/TLA (Lamport's Temporal Logic of Actions): major reorganization
  7079 -- avoids syntactic ambiguities and treats state, transition, and
  7080 temporal levels more uniformly; introduces INCOMPATIBILITIES due to
  7081 changed syntax and (many) tactics;
  7082 
  7083 * HOL/inductive: Now also handles more general introduction rules such
  7084   as "ALL y. (y, x) : r --> y : acc r ==> x : acc r"; monotonicity
  7085   theorems are now maintained within the theory (maintained via the
  7086   "mono" attribute);
  7087 
  7088 * HOL/datatype: Now also handles arbitrarily branching datatypes
  7089   (using function types) such as
  7090 
  7091   datatype 'a tree = Atom 'a | Branch "nat => 'a tree"
  7092 
  7093 * HOL/record: record_simproc (part of the default simpset) takes care
  7094 of selectors applied to updated records; record_split_tac is no longer
  7095 part of the default claset; update_defs may now be removed from the
  7096 simpset in many cases; COMPATIBILITY: old behavior achieved by
  7097 
  7098   claset_ref () := claset() addSWrapper record_split_wrapper;
  7099   Delsimprocs [record_simproc]
  7100 
  7101 * HOL/typedef: fixed type inference for representing set; type
  7102 arguments now have to occur explicitly on the rhs as type constraints;
  7103 
  7104 * HOL/recdef (TFL): 'congs' syntax now expects comma separated list of theorem
  7105 names rather than an ML expression;
  7106 
  7107 * HOL/defer_recdef (TFL): like recdef but the well-founded relation can be
  7108 supplied later.  Program schemes can be defined, such as
  7109     "While B C s = (if B s then While B C (C s) else s)"
  7110 where the well-founded relation can be chosen after B and C have been given.
  7111 
  7112 * HOL/List: the constructors of type list are now Nil and Cons;
  7113 INCOMPATIBILITY: while [] and infix # syntax is still there, of
  7114 course, ML tools referring to List.list.op # etc. have to be adapted;
  7115 
  7116 * HOL_quantifiers flag superseded by "HOL" print mode, which is
  7117 disabled by default; run isabelle with option -m HOL to get back to
  7118 the original Gordon/HOL-style output;
  7119 
  7120 * HOL/Ord.thy: new bounded quantifier syntax (input only): ALL x<y. P,
  7121 ALL x<=y. P, EX x<y. P, EX x<=y. P;
  7122 
  7123 * HOL basic syntax simplified (more orthogonal): all variants of
  7124 All/Ex now support plain / symbolic / HOL notation; plain syntax for
  7125 Eps operator is provided as well: "SOME x. P[x]";
  7126 
  7127 * HOL/Sum.thy: sum_case has been moved to HOL/Datatype;
  7128 
  7129 * HOL/Univ.thy: infix syntax <*>, <+>, <**>, <+> eliminated and made
  7130 thus available for user theories;
  7131 
  7132 * HOLCF/IOA/Sequents: renamed 'Cons' to 'Consq' to avoid clash with
  7133 HOL/List; hardly an INCOMPATIBILITY since '>>' syntax is used all the
  7134 time;
  7135 
  7136 * HOL: new tactic smp_tac: int -> int -> tactic, which applies spec
  7137 several times and then mp;
  7138 
  7139 
  7140 *** LK ***
  7141 
  7142 * the notation <<...>> is now available as a notation for sequences of
  7143 formulas;
  7144 
  7145 * the simplifier is now installed
  7146 
  7147 * the axiom system has been generalized (thanks to Soren Heilmann)
  7148 
  7149 * the classical reasoner now has a default rule database
  7150 
  7151 
  7152 *** ZF ***
  7153 
  7154 * new primrec section allows primitive recursive functions to be given
  7155 directly (as in HOL) over datatypes and the natural numbers;
  7156 
  7157 * new tactics induct_tac and exhaust_tac for induction (or case
  7158 analysis) over datatypes and the natural numbers;
  7159 
  7160 * the datatype declaration of type T now defines the recursor T_rec;
  7161 
  7162 * simplification automatically does freeness reasoning for datatype
  7163 constructors;
  7164 
  7165 * automatic type-inference, with AddTCs command to insert new
  7166 type-checking rules;
  7167 
  7168 * datatype introduction rules are now added as Safe Introduction rules
  7169 to the claset;
  7170 
  7171 * the syntax "if P then x else y" is now available in addition to
  7172 if(P,x,y);
  7173 
  7174 
  7175 *** Internal programming interfaces ***
  7176 
  7177 * tuned simplifier trace output; new flag debug_simp;
  7178 
  7179 * structures Vartab / Termtab (instances of TableFun) offer efficient
  7180 tables indexed by indexname_ord / term_ord (compatible with aconv);
  7181 
  7182 * AxClass.axclass_tac lost the theory argument;
  7183 
  7184 * tuned current_goals_markers semantics: begin / end goal avoids
  7185 printing empty lines;
  7186 
  7187 * removed prs and prs_fn hook, which was broken because it did not
  7188 include \n in its semantics, forcing writeln to add one
  7189 uncoditionally; replaced prs_fn by writeln_fn; consider std_output:
  7190 string -> unit if you really want to output text without newline;
  7191 
  7192 * Symbol.output subject to print mode; INCOMPATIBILITY: defaults to
  7193 plain output, interface builders may have to enable 'isabelle_font'
  7194 mode to get Isabelle font glyphs as before;
  7195 
  7196 * refined token_translation interface; INCOMPATIBILITY: output length
  7197 now of type real instead of int;
  7198 
  7199 * theory loader actions may be traced via new ThyInfo.add_hook
  7200 interface (see src/Pure/Thy/thy_info.ML); example application: keep
  7201 your own database of information attached to *whole* theories -- as
  7202 opposed to intra-theory data slots offered via TheoryDataFun;
  7203 
  7204 * proper handling of dangling sort hypotheses (at last!);
  7205 Thm.strip_shyps and Drule.strip_shyps_warning take care of removing
  7206 extra sort hypotheses that can be witnessed from the type signature;
  7207 the force_strip_shyps flag is gone, any remaining shyps are simply
  7208 left in the theorem (with a warning issued by strip_shyps_warning);
  7209 
  7210 
  7211 
  7212 New in Isabelle98-1 (October 1998)
  7213 ----------------------------------
  7214 
  7215 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  7216 
  7217 * several changes of automated proof tools;
  7218 
  7219 * HOL: major changes to the inductive and datatype packages, including
  7220 some minor incompatibilities of theory syntax;
  7221 
  7222 * HOL: renamed r^-1 to 'converse' from 'inverse'; 'inj_onto' is now
  7223 called `inj_on';
  7224 
  7225 * HOL: removed duplicate thms in Arith:
  7226   less_imp_add_less  should be replaced by  trans_less_add1
  7227   le_imp_add_le      should be replaced by  trans_le_add1
  7228 
  7229 * HOL: unary minus is now overloaded (new type constraints may be
  7230 required);
  7231 
  7232 * HOL and ZF: unary minus for integers is now #- instead of #~.  In
  7233 ZF, expressions such as n#-1 must be changed to n#- 1, since #-1 is
  7234 now taken as an integer constant.
  7235 
  7236 * Pure: ML function 'theory_of' renamed to 'theory';
  7237 
  7238 
  7239 *** Proof tools ***
  7240 
  7241 * Simplifier:
  7242   1. Asm_full_simp_tac is now more aggressive.
  7243      1. It will sometimes reorient premises if that increases their power to
  7244         simplify.
  7245      2. It does no longer proceed strictly from left to right but may also
  7246         rotate premises to achieve further simplification.
  7247      For compatibility reasons there is now Asm_lr_simp_tac which is like the
  7248      old Asm_full_simp_tac in that it does not rotate premises.
  7249   2. The simplifier now knows a little bit about nat-arithmetic.
  7250 
  7251 * Classical reasoner: wrapper mechanism for the classical reasoner now
  7252 allows for selected deletion of wrappers, by introduction of names for
  7253 wrapper functionals.  This implies that addbefore, addSbefore,
  7254 addaltern, and addSaltern now take a pair (name, tactic) as argument,
  7255 and that adding two tactics with the same name overwrites the first
  7256 one (emitting a warning).
  7257   type wrapper = (int -> tactic) -> (int -> tactic)
  7258   setWrapper, setSWrapper, compWrapper and compSWrapper are replaced by
  7259   addWrapper, addSWrapper: claset * (string * wrapper) -> claset
  7260   delWrapper, delSWrapper: claset *  string            -> claset
  7261   getWrapper is renamed to appWrappers, getSWrapper to appSWrappers;
  7262 
  7263 * Classical reasoner: addbefore/addSbefore now have APPEND/ORELSE
  7264 semantics; addbefore now affects only the unsafe part of step_tac
  7265 etc.; this affects addss/auto_tac/force_tac, so EXISTING PROOFS MAY
  7266 FAIL, but proofs should be fixable easily, e.g. by replacing Auto_tac
  7267 by Force_tac;
  7268 
  7269 * Classical reasoner: setwrapper to setWrapper and compwrapper to
  7270 compWrapper; added safe wrapper (and access functions for it);
  7271 
  7272 * HOL/split_all_tac is now much faster and fails if there is nothing
  7273 to split.  Some EXISTING PROOFS MAY REQUIRE ADAPTION because the order
  7274 and the names of the automatically generated variables have changed.
  7275 split_all_tac has moved within claset() from unsafe wrappers to safe
  7276 wrappers, which means that !!-bound variables are split much more
  7277 aggressively, and safe_tac and clarify_tac now split such variables.
  7278 If this splitting is not appropriate, use delSWrapper "split_all_tac".
  7279 Note: the same holds for record_split_tac, which does the job of
  7280 split_all_tac for record fields.
  7281 
  7282 * HOL/Simplifier: Rewrite rules for case distinctions can now be added
  7283 permanently to the default simpset using Addsplits just like
  7284 Addsimps. They can be removed via Delsplits just like
  7285 Delsimps. Lower-case versions are also available.
  7286 
  7287 * HOL/Simplifier: The rule split_if is now part of the default
  7288 simpset. This means that the simplifier will eliminate all occurrences
  7289 of if-then-else in the conclusion of a goal. To prevent this, you can
  7290 either remove split_if completely from the default simpset by
  7291 `Delsplits [split_if]' or remove it in a specific call of the
  7292 simplifier using `... delsplits [split_if]'.  You can also add/delete
  7293 other case splitting rules to/from the default simpset: every datatype
  7294 generates suitable rules `split_t_case' and `split_t_case_asm' (where
  7295 t is the name of the datatype).
  7296 
  7297 * Classical reasoner / Simplifier combination: new force_tac (and
  7298 derivatives Force_tac, force) combines rewriting and classical
  7299 reasoning (and whatever other tools) similarly to auto_tac, but is
  7300 aimed to solve the given subgoal completely.
  7301 
  7302 
  7303 *** General ***
  7304 
  7305 * new top-level commands `Goal' and `Goalw' that improve upon `goal'
  7306 and `goalw': the theory is no longer needed as an explicit argument -
  7307 the current theory context is used; assumptions are no longer returned
  7308 at the ML-level unless one of them starts with ==> or !!; it is
  7309 recommended to convert to these new commands using isatool fixgoal
  7310 (backup your sources first!);
  7311 
  7312 * new top-level commands 'thm' and 'thms' for retrieving theorems from
  7313 the current theory context, and 'theory' to lookup stored theories;
  7314 
  7315 * new theory section 'locale' for declaring constants, assumptions and
  7316 definitions that have local scope;
  7317 
  7318 * new theory section 'nonterminals' for purely syntactic types;
  7319 
  7320 * new theory section 'setup' for generic ML setup functions
  7321 (e.g. package initialization);
  7322 
  7323 * the distribution now includes Isabelle icons: see
  7324 lib/logo/isabelle-{small,tiny}.xpm;
  7325 
  7326 * isatool install - install binaries with absolute references to
  7327 ISABELLE_HOME/bin;
  7328 
  7329 * isatool logo -- create instances of the Isabelle logo (as EPS);
  7330 
  7331 * print mode 'emacs' reserved for Isamode;
  7332 
  7333 * support multiple print (ast) translations per constant name;
  7334 
  7335 * theorems involving oracles are now printed with a suffixed [!];
  7336 
  7337 
  7338 *** HOL ***
  7339 
  7340 * there is now a tutorial on Isabelle/HOL (do 'isatool doc tutorial');
  7341 
  7342 * HOL/inductive package reorganized and improved: now supports mutual
  7343 definitions such as
  7344 
  7345   inductive EVEN ODD
  7346     intrs
  7347       null "0 : EVEN"
  7348       oddI "n : EVEN ==> Suc n : ODD"
  7349       evenI "n : ODD ==> Suc n : EVEN"
  7350 
  7351 new theorem list "elims" contains an elimination rule for each of the
  7352 recursive sets; inductive definitions now handle disjunctive premises
  7353 correctly (also ZF);
  7354 
  7355 INCOMPATIBILITIES: requires Inductive as an ancestor; component
  7356 "mutual_induct" no longer exists - the induction rule is always
  7357 contained in "induct";
  7358 
  7359 
  7360 * HOL/datatype package re-implemented and greatly improved: now
  7361 supports mutually recursive datatypes such as
  7362 
  7363   datatype
  7364     'a aexp = IF_THEN_ELSE ('a bexp) ('a aexp) ('a aexp)
  7365             | SUM ('a aexp) ('a aexp)
  7366             | DIFF ('a aexp) ('a aexp)
  7367             | NUM 'a
  7368   and
  7369     'a bexp = LESS ('a aexp) ('a aexp)
  7370             | AND ('a bexp) ('a bexp)
  7371             | OR ('a bexp) ('a bexp)
  7372 
  7373 as well as indirectly recursive datatypes such as
  7374 
  7375   datatype
  7376     ('a, 'b) term = Var 'a
  7377                   | App 'b ((('a, 'b) term) list)
  7378 
  7379 The new tactic  mutual_induct_tac [<var_1>, ..., <var_n>] i  performs
  7380 induction on mutually / indirectly recursive datatypes.
  7381 
  7382 Primrec equations are now stored in theory and can be accessed via
  7383 <function_name>.simps.
  7384 
  7385 INCOMPATIBILITIES:
  7386 
  7387   - Theories using datatypes must now have theory Datatype as an
  7388     ancestor.
  7389   - The specific <typename>.induct_tac no longer exists - use the
  7390     generic induct_tac instead.
  7391   - natE has been renamed to nat.exhaust - use exhaust_tac
  7392     instead of res_inst_tac ... natE. Note that the variable
  7393     names in nat.exhaust differ from the names in natE, this
  7394     may cause some "fragile" proofs to fail.
  7395   - The theorems split_<typename>_case and split_<typename>_case_asm
  7396     have been renamed to <typename>.split and <typename>.split_asm.
  7397   - Since default sorts of type variables are now handled correctly,
  7398     some datatype definitions may have to be annotated with explicit
  7399     sort constraints.
  7400   - Primrec definitions no longer require function name and type
  7401     of recursive argument.
  7402 
  7403 Consider using isatool fixdatatype to adapt your theories and proof
  7404 scripts to the new package (backup your sources first!).
  7405 
  7406 
  7407 * HOL/record package: considerably improved implementation; now
  7408 includes concrete syntax for record types, terms, updates; theorems
  7409 for surjective pairing and splitting !!-bound record variables; proof
  7410 support is as follows:
  7411 
  7412   1) standard conversions (selectors or updates applied to record
  7413 constructor terms) are part of the standard simpset;
  7414 
  7415   2) inject equations of the form ((x, y) = (x', y')) == x=x' & y=y' are
  7416 made part of standard simpset and claset via addIffs;
  7417 
  7418   3) a tactic for record field splitting (record_split_tac) is part of
  7419 the standard claset (addSWrapper);
  7420 
  7421 To get a better idea about these rules you may retrieve them via
  7422 something like 'thms "foo.simps"' or 'thms "foo.iffs"', where "foo" is
  7423 the name of your record type.
  7424 
  7425 The split tactic 3) conceptually simplifies by the following rule:
  7426 
  7427   "(!!x. PROP ?P x) == (!!a b. PROP ?P (a, b))"
  7428 
  7429 Thus any record variable that is bound by meta-all will automatically
  7430 blow up into some record constructor term, consequently the
  7431 simplifications of 1), 2) apply.  Thus force_tac, auto_tac etc. shall
  7432 solve record problems automatically.
  7433 
  7434 
  7435 * reorganized the main HOL image: HOL/Integ and String loaded by
  7436 default; theory Main includes everything;
  7437 
  7438 * automatic simplification of integer sums and comparisons, using cancellation;
  7439 
  7440 * added option_map_eq_Some and not_Some_eq to the default simpset and claset;
  7441 
  7442 * added disj_not1 = "(~P | Q) = (P --> Q)" to the default simpset;
  7443 
  7444 * many new identities for unions, intersections, set difference, etc.;
  7445 
  7446 * expand_if, expand_split, expand_sum_case and expand_nat_case are now
  7447 called split_if, split_split, split_sum_case and split_nat_case (to go
  7448 with add/delsplits);
  7449 
  7450 * HOL/Prod introduces simplification procedure unit_eq_proc rewriting
  7451 (?x::unit) = (); this is made part of the default simpset, which COULD
  7452 MAKE EXISTING PROOFS FAIL under rare circumstances (consider
  7453 'Delsimprocs [unit_eq_proc];' as last resort); also note that
  7454 unit_abs_eta_conv is added in order to counter the effect of
  7455 unit_eq_proc on (%u::unit. f u), replacing it by f rather than by
  7456 %u.f();
  7457 
  7458 * HOL/Fun INCOMPATIBILITY: `inj_onto' is now called `inj_on' (which
  7459 makes more sense);
  7460 
  7461 * HOL/Set INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
  7462   It and 'sym RS equals0D' are now in the default  claset, giving automatic
  7463   disjointness reasoning but breaking a few old proofs.
  7464 
  7465 * HOL/Relation INCOMPATIBILITY: renamed the relational operator r^-1
  7466 to 'converse' from 'inverse' (for compatibility with ZF and some
  7467 literature);
  7468 
  7469 * HOL/recdef can now declare non-recursive functions, with {} supplied as
  7470 the well-founded relation;
  7471 
  7472 * HOL/Set INCOMPATIBILITY: the complement of set A is now written -A instead of
  7473     Compl A.  The "Compl" syntax remains available as input syntax for this
  7474     release ONLY.
  7475 
  7476 * HOL/Update: new theory of function updates:
  7477     f(a:=b) == %x. if x=a then b else f x
  7478 may also be iterated as in f(a:=b,c:=d,...);
  7479 
  7480 * HOL/Vimage: new theory for inverse image of a function, syntax f-``B;
  7481 
  7482 * HOL/List:
  7483   - new function list_update written xs[i:=v] that updates the i-th
  7484     list position. May also be iterated as in xs[i:=a,j:=b,...].
  7485   - new function `upt' written [i..j(] which generates the list
  7486     [i,i+1,...,j-1], i.e. the upper bound is excluded. To include the upper
  7487     bound write [i..j], which is a shorthand for [i..j+1(].
  7488   - new lexicographic orderings and corresponding wellfoundedness theorems.
  7489 
  7490 * HOL/Arith:
  7491   - removed 'pred' (predecessor) function;
  7492   - generalized some theorems about n-1;
  7493   - many new laws about "div" and "mod";
  7494   - new laws about greatest common divisors (see theory ex/Primes);
  7495 
  7496 * HOL/Relation: renamed the relational operator r^-1 "converse"
  7497 instead of "inverse";
  7498 
  7499 * HOL/Induct/Multiset: a theory of multisets, including the wellfoundedness
  7500   of the multiset ordering;
  7501 
  7502 * directory HOL/Real: a construction of the reals using Dedekind cuts
  7503   (not included by default);
  7504 
  7505 * directory HOL/UNITY: Chandy and Misra's UNITY formalism;
  7506 
  7507 * directory HOL/Hoare: a new version of Hoare logic which permits many-sorted
  7508   programs, i.e. different program variables may have different types.
  7509 
  7510 * calling (stac rew i) now fails if "rew" has no effect on the goal
  7511   [previously, this check worked only if the rewrite rule was unconditional]
  7512   Now rew can involve either definitions or equalities (either == or =).
  7513 
  7514 
  7515 *** ZF ***
  7516 
  7517 * theory Main includes everything; INCOMPATIBILITY: theory ZF.thy contains
  7518   only the theorems proved on ZF.ML;
  7519 
  7520 * ZF INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
  7521   It and 'sym RS equals0D' are now in the default  claset, giving automatic
  7522   disjointness reasoning but breaking a few old proofs.
  7523 
  7524 * ZF/Update: new theory of function updates
  7525     with default rewrite rule  f(x:=y) ` z = if(z=x, y, f`z)
  7526   may also be iterated as in f(a:=b,c:=d,...);
  7527 
  7528 * in  let x=t in u(x), neither t nor u(x) has to be an FOL term.
  7529 
  7530 * calling (stac rew i) now fails if "rew" has no effect on the goal
  7531   [previously, this check worked only if the rewrite rule was unconditional]
  7532   Now rew can involve either definitions or equalities (either == or =).
  7533 
  7534 * case_tac provided for compatibility with HOL
  7535     (like the old excluded_middle_tac, but with subgoals swapped)
  7536 
  7537 
  7538 *** Internal programming interfaces ***
  7539 
  7540 * Pure: several new basic modules made available for general use, see
  7541 also src/Pure/README;
  7542 
  7543 * improved the theory data mechanism to support encapsulation (data
  7544 kind name replaced by private Object.kind, acting as authorization
  7545 key); new type-safe user interface via functor TheoryDataFun; generic
  7546 print_data function becomes basically useless;
  7547 
  7548 * removed global_names compatibility flag -- all theory declarations
  7549 are qualified by default;
  7550 
  7551 * module Pure/Syntax now offers quote / antiquote translation
  7552 functions (useful for Hoare logic etc. with implicit dependencies);
  7553 see HOL/ex/Antiquote for an example use;
  7554 
  7555 * Simplifier now offers conversions (asm_)(full_)rewrite: simpset ->
  7556 cterm -> thm;
  7557 
  7558 * new tactical CHANGED_GOAL for checking that a tactic modifies a
  7559 subgoal;
  7560 
  7561 * Display.print_goals function moved to Locale.print_goals;
  7562 
  7563 * standard print function for goals supports current_goals_markers
  7564 variable for marking begin of proof, end of proof, start of goal; the
  7565 default is ("", "", ""); setting current_goals_markers := ("<proof>",
  7566 "</proof>", "<goal>") causes SGML like tagged proof state printing,
  7567 for example;
  7568 
  7569 
  7570 
  7571 New in Isabelle98 (January 1998)
  7572 --------------------------------
  7573 
  7574 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  7575 
  7576 * changed lexical syntax of terms / types: dots made part of long
  7577 identifiers, e.g. "%x.x" no longer possible, should be "%x. x";
  7578 
  7579 * simpset (and claset) reference variable replaced by functions
  7580 simpset / simpset_ref;
  7581 
  7582 * no longer supports theory aliases (via merge) and non-trivial
  7583 implicit merge of thms' signatures;
  7584 
  7585 * most internal names of constants changed due to qualified names;
  7586 
  7587 * changed Pure/Sequence interface (see Pure/seq.ML);
  7588 
  7589 
  7590 *** General Changes ***
  7591 
  7592 * hierachically structured name spaces (for consts, types, axms, thms
  7593 etc.); new lexical class 'longid' (e.g. Foo.bar.x) may render much of
  7594 old input syntactically incorrect (e.g. "%x.x"); COMPATIBILITY:
  7595 isatool fixdots ensures space after dots (e.g. "%x. x"); set
  7596 long_names for fully qualified output names; NOTE: ML programs
  7597 (special tactics, packages etc.) referring to internal names may have
  7598 to be adapted to cope with fully qualified names; in case of severe
  7599 backward campatibility problems try setting 'global_names' at compile
  7600 time to have enrything declared within a flat name space; one may also
  7601 fine tune name declarations in theories via the 'global' and 'local'
  7602 section;
  7603 
  7604 * reimplemented the implicit simpset and claset using the new anytype
  7605 data filed in signatures; references simpset:simpset ref etc. are
  7606 replaced by functions simpset:unit->simpset and
  7607 simpset_ref:unit->simpset ref; COMPATIBILITY: use isatool fixclasimp
  7608 to patch your ML files accordingly;
  7609 
  7610 * HTML output now includes theory graph data for display with Java
  7611 applet or isatool browser; data generated automatically via isatool
  7612 usedir (see -i option, ISABELLE_USEDIR_OPTIONS);
  7613 
  7614 * defs may now be conditional; improved rewrite_goals_tac to handle
  7615 conditional equations;
  7616 
  7617 * defs now admits additional type arguments, using TYPE('a) syntax;
  7618 
  7619 * theory aliases via merge (e.g. M=A+B+C) no longer supported, always
  7620 creates a new theory node; implicit merge of thms' signatures is
  7621 restricted to 'trivial' ones; COMPATIBILITY: one may have to use
  7622 transfer:theory->thm->thm in (rare) cases;
  7623 
  7624 * improved handling of draft signatures / theories; draft thms (and
  7625 ctyps, cterms) are automatically promoted to real ones;
  7626 
  7627 * slightly changed interfaces for oracles: admit many per theory, named
  7628 (e.g. oracle foo = mlfun), additional name argument for invoke_oracle;
  7629 
  7630 * print_goals: optional output of const types (set show_consts and
  7631 show_types);
  7632 
  7633 * improved output of warnings (###) and errors (***);
  7634 
  7635 * subgoal_tac displays a warning if the new subgoal has type variables;
  7636 
  7637 * removed old README and Makefiles;
  7638 
  7639 * replaced print_goals_ref hook by print_current_goals_fn and result_error_fn;
  7640 
  7641 * removed obsolete init_pps and init_database;
  7642 
  7643 * deleted the obsolete tactical STATE, which was declared by
  7644     fun STATE tacfun st = tacfun st st;
  7645 
  7646 * cd and use now support path variables, e.g. $ISABELLE_HOME, or ~
  7647 (which abbreviates $HOME);
  7648 
  7649 * changed Pure/Sequence interface (see Pure/seq.ML); COMPATIBILITY:
  7650 use isatool fixseq to adapt your ML programs (this works for fully
  7651 qualified references to the Sequence structure only!);
  7652 
  7653 * use_thy no longer requires writable current directory; it always
  7654 reloads .ML *and* .thy file, if either one is out of date;
  7655 
  7656 
  7657 *** Classical Reasoner ***
  7658 
  7659 * Clarify_tac, clarify_tac, clarify_step_tac, Clarify_step_tac: new
  7660 tactics that use classical reasoning to simplify a subgoal without
  7661 splitting it into several subgoals;
  7662 
  7663 * Safe_tac: like safe_tac but uses the default claset;
  7664 
  7665 
  7666 *** Simplifier ***
  7667 
  7668 * added simplification meta rules:
  7669     (asm_)(full_)simplify: simpset -> thm -> thm;
  7670 
  7671 * simplifier.ML no longer part of Pure -- has to be loaded by object
  7672 logics (again);
  7673 
  7674 * added prems argument to simplification procedures;
  7675 
  7676 * HOL, FOL, ZF: added infix function `addsplits':
  7677   instead of `<simpset> setloop (split_tac <thms>)'
  7678   you can simply write `<simpset> addsplits <thms>'
  7679 
  7680 
  7681 *** Syntax ***
  7682 
  7683 * TYPE('a) syntax for type reflection terms;
  7684 
  7685 * no longer handles consts with name "" -- declare as 'syntax' instead;
  7686 
  7687 * pretty printer: changed order of mixfix annotation preference (again!);
  7688 
  7689 * Pure: fixed idt/idts vs. pttrn/pttrns syntactic categories;
  7690 
  7691 
  7692 *** HOL ***
  7693 
  7694 * HOL: there is a new splitter `split_asm_tac' that can be used e.g.
  7695   with `addloop' of the simplifier to faciliate case splitting in premises.
  7696 
  7697 * HOL/TLA: Stephan Merz's formalization of Lamport's Temporal Logic of Actions;
  7698 
  7699 * HOL/Auth: new protocol proofs including some for the Internet
  7700   protocol TLS;
  7701 
  7702 * HOL/Map: new theory of `maps' a la VDM;
  7703 
  7704 * HOL/simplifier: simplification procedures nat_cancel_sums for
  7705 cancelling out common nat summands from =, <, <= (in)equalities, or
  7706 differences; simplification procedures nat_cancel_factor for
  7707 cancelling common factor from =, <, <= (in)equalities over natural
  7708 sums; nat_cancel contains both kinds of procedures, it is installed by
  7709 default in Arith.thy -- this COULD MAKE EXISTING PROOFS FAIL;
  7710 
  7711 * HOL/simplifier: terms of the form
  7712   `? x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x)'  (or t=x)
  7713   are rewritten to
  7714   `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t)',
  7715   and those of the form
  7716   `! x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x) --> R(x)'  (or t=x)
  7717   are rewritten to
  7718   `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t) --> R(t)',
  7719 
  7720 * HOL/datatype
  7721   Each datatype `t' now comes with a theorem `split_t_case' of the form
  7722 
  7723   P(t_case f1 ... fn x) =
  7724      ( (!y1 ... ym1. x = C1 y1 ... ym1 --> P(f1 y1 ... ym1)) &
  7725         ...
  7726        (!y1 ... ymn. x = Cn y1 ... ymn --> P(f1 y1 ... ymn))
  7727      )
  7728 
  7729   and a theorem `split_t_case_asm' of the form
  7730 
  7731   P(t_case f1 ... fn x) =
  7732     ~( (? y1 ... ym1. x = C1 y1 ... ym1 & ~P(f1 y1 ... ym1)) |
  7733         ...
  7734        (? y1 ... ymn. x = Cn y1 ... ymn & ~P(f1 y1 ... ymn))
  7735      )
  7736   which can be added to a simpset via `addsplits'. The existing theorems
  7737   expand_list_case and expand_option_case have been renamed to
  7738   split_list_case and split_option_case.
  7739 
  7740 * HOL/Arithmetic:
  7741   - `pred n' is automatically converted to `n-1'.
  7742     Users are strongly encouraged not to use `pred' any longer,
  7743     because it will disappear altogether at some point.
  7744   - Users are strongly encouraged to write "0 < n" rather than
  7745     "n ~= 0". Theorems and proof tools have been modified towards this
  7746     `standard'.
  7747 
  7748 * HOL/Lists:
  7749   the function "set_of_list" has been renamed "set" (and its theorems too);
  7750   the function "nth" now takes its arguments in the reverse order and
  7751   has acquired the infix notation "!" as in "xs!n".
  7752 
  7753 * HOL/Set: UNIV is now a constant and is no longer translated to Compl{};
  7754 
  7755 * HOL/Set: The operator (UN x.B x) now abbreviates (UN x:UNIV. B x) and its
  7756   specialist theorems (like UN1_I) are gone.  Similarly for (INT x.B x);
  7757 
  7758 * HOL/record: extensible records with schematic structural subtyping
  7759 (single inheritance); EXPERIMENTAL version demonstrating the encoding,
  7760 still lacks various theorems and concrete record syntax;
  7761 
  7762 
  7763 *** HOLCF ***
  7764 
  7765 * removed "axioms" and "generated by" sections;
  7766 
  7767 * replaced "ops" section by extended "consts" section, which is capable of
  7768   handling the continuous function space "->" directly;
  7769 
  7770 * domain package:
  7771   . proves theorems immediately and stores them in the theory,
  7772   . creates hierachical name space,
  7773   . now uses normal mixfix annotations (instead of cinfix...),
  7774   . minor changes to some names and values (for consistency),
  7775   . e.g. cases -> casedist, dists_eq -> dist_eqs, [take_lemma] -> take_lemmas,
  7776   . separator between mutual domain defs: changed "," to "and",
  7777   . improved handling of sort constraints;  now they have to
  7778     appear on the left-hand side of the equations only;
  7779 
  7780 * fixed LAM <x,y,zs>.b syntax;
  7781 
  7782 * added extended adm_tac to simplifier in HOLCF -- can now discharge
  7783 adm (%x. P (t x)), where P is chainfinite and t continuous;
  7784 
  7785 
  7786 *** FOL and ZF ***
  7787 
  7788 * FOL: there is a new splitter `split_asm_tac' that can be used e.g.
  7789   with `addloop' of the simplifier to faciliate case splitting in premises.
  7790 
  7791 * qed_spec_mp, qed_goal_spec_mp, qed_goalw_spec_mp are available, as
  7792 in HOL, they strip ALL and --> from proved theorems;
  7793 
  7794 
  7795 
  7796 New in Isabelle94-8 (May 1997)
  7797 ------------------------------
  7798 
  7799 *** General Changes ***
  7800 
  7801 * new utilities to build / run / maintain Isabelle etc. (in parts
  7802 still somewhat experimental); old Makefiles etc. still functional;
  7803 
  7804 * new 'Isabelle System Manual';
  7805 
  7806 * INSTALL text, together with ./configure and ./build scripts;
  7807 
  7808 * reimplemented type inference for greater efficiency, better error
  7809 messages and clean internal interface;
  7810 
  7811 * prlim command for dealing with lots of subgoals (an easier way of
  7812 setting goals_limit);
  7813 
  7814 
  7815 *** Syntax ***
  7816 
  7817 * supports alternative (named) syntax tables (parser and pretty
  7818 printer); internal interface is provided by add_modesyntax(_i);
  7819 
  7820 * Pure, FOL, ZF, HOL, HOLCF now support symbolic input and output; to
  7821 be used in conjunction with the Isabelle symbol font; uses the
  7822 "symbols" syntax table;
  7823 
  7824 * added token_translation interface (may translate name tokens in
  7825 arbitrary ways, dependent on their type (free, bound, tfree, ...) and
  7826 the current print_mode); IMPORTANT: user print translation functions
  7827 are responsible for marking newly introduced bounds
  7828 (Syntax.mark_boundT);
  7829 
  7830 * token translations for modes "xterm" and "xterm_color" that display
  7831 names in bold, underline etc. or colors (which requires a color
  7832 version of xterm);
  7833 
  7834 * infixes may now be declared with names independent of their syntax;
  7835 
  7836 * added typed_print_translation (like print_translation, but may
  7837 access type of constant);
  7838 
  7839 
  7840 *** Classical Reasoner ***
  7841 
  7842 Blast_tac: a new tactic!  It is often more powerful than fast_tac, but has
  7843 some limitations.  Blast_tac...
  7844   + ignores addss, addbefore, addafter; this restriction is intrinsic
  7845   + ignores elimination rules that don't have the correct format
  7846         (the conclusion MUST be a formula variable)
  7847   + ignores types, which can make HOL proofs fail
  7848   + rules must not require higher-order unification, e.g. apply_type in ZF
  7849     [message "Function Var's argument not a bound variable" relates to this]
  7850   + its proof strategy is more general but can actually be slower
  7851 
  7852 * substitution with equality assumptions no longer permutes other
  7853 assumptions;
  7854 
  7855 * minor changes in semantics of addafter (now called addaltern); renamed
  7856 setwrapper to setWrapper and compwrapper to compWrapper; added safe wrapper
  7857 (and access functions for it);
  7858 
  7859 * improved combination of classical reasoner and simplifier:
  7860   + functions for handling clasimpsets
  7861   + improvement of addss: now the simplifier is called _after_ the
  7862     safe steps.
  7863   + safe variant of addss called addSss: uses safe simplifications
  7864     _during_ the safe steps. It is more complete as it allows multiple
  7865     instantiations of unknowns (e.g. with slow_tac).
  7866 
  7867 *** Simplifier ***
  7868 
  7869 * added interface for simplification procedures (functions that
  7870 produce *proven* rewrite rules on the fly, depending on current
  7871 redex);
  7872 
  7873 * ordering on terms as parameter (used for ordered rewriting);
  7874 
  7875 * new functions delcongs, deleqcongs, and Delcongs. richer rep_ss;
  7876 
  7877 * the solver is now split into a safe and an unsafe part.
  7878 This should be invisible for the normal user, except that the
  7879 functions setsolver and addsolver have been renamed to setSolver and
  7880 addSolver; added safe_asm_full_simp_tac;
  7881 
  7882 
  7883 *** HOL ***
  7884 
  7885 * a generic induction tactic `induct_tac' which works for all datatypes and
  7886 also for type `nat';
  7887 
  7888 * a generic case distinction tactic `exhaust_tac' which works for all
  7889 datatypes and also for type `nat';
  7890 
  7891 * each datatype comes with a function `size';
  7892 
  7893 * patterns in case expressions allow tuple patterns as arguments to
  7894 constructors, for example `case x of [] => ... | (x,y,z)#ps => ...';
  7895 
  7896 * primrec now also works with type nat;
  7897 
  7898 * recdef: a new declaration form, allows general recursive functions to be
  7899 defined in theory files.  See HOL/ex/Fib, HOL/ex/Primes, HOL/Subst/Unify.
  7900 
  7901 * the constant for negation has been renamed from "not" to "Not" to
  7902 harmonize with FOL, ZF, LK, etc.;
  7903 
  7904 * HOL/ex/LFilter theory of a corecursive "filter" functional for
  7905 infinite lists;
  7906 
  7907 * HOL/Modelcheck demonstrates invocation of model checker oracle;
  7908 
  7909 * HOL/ex/Ring.thy declares cring_simp, which solves equational
  7910 problems in commutative rings, using axiomatic type classes for + and *;
  7911 
  7912 * more examples in HOL/MiniML and HOL/Auth;
  7913 
  7914 * more default rewrite rules for quantifiers, union/intersection;
  7915 
  7916 * a new constant `arbitrary == @x.False';
  7917 
  7918 * HOLCF/IOA replaces old HOL/IOA;
  7919 
  7920 * HOLCF changes: derived all rules and arities
  7921   + axiomatic type classes instead of classes
  7922   + typedef instead of faking type definitions
  7923   + eliminated the internal constants less_fun, less_cfun, UU_fun, UU_cfun etc.
  7924   + new axclasses cpo, chfin, flat with flat < chfin < pcpo < cpo < po
  7925   + eliminated the types void, one, tr
  7926   + use unit lift and bool lift (with translations) instead of one and tr
  7927   + eliminated blift from Lift3.thy (use Def instead of blift)
  7928   all eliminated rules are derived as theorems --> no visible changes ;
  7929 
  7930 
  7931 *** ZF ***
  7932 
  7933 * ZF now has Fast_tac, Simp_tac and Auto_tac.  Union_iff is a now a default
  7934 rewrite rule; this may affect some proofs.  eq_cs is gone but can be put back
  7935 as ZF_cs addSIs [equalityI];
  7936 
  7937 
  7938 
  7939 New in Isabelle94-7 (November 96)
  7940 ---------------------------------
  7941 
  7942 * allowing negative levels (as offsets) in prlev and choplev;
  7943 
  7944 * super-linear speedup for large simplifications;
  7945 
  7946 * FOL, ZF and HOL now use miniscoping: rewriting pushes
  7947 quantifications in as far as possible (COULD MAKE EXISTING PROOFS
  7948 FAIL); can suppress it using the command Delsimps (ex_simps @
  7949 all_simps); De Morgan laws are also now included, by default;
  7950 
  7951 * improved printing of ==>  :  ~:
  7952 
  7953 * new object-logic "Sequents" adds linear logic, while replacing LK
  7954 and Modal (thanks to Sara Kalvala);
  7955 
  7956 * HOL/Auth: correctness proofs for authentication protocols;
  7957 
  7958 * HOL: new auto_tac combines rewriting and classical reasoning (many
  7959 examples on HOL/Auth);
  7960 
  7961 * HOL: new command AddIffs for declaring theorems of the form P=Q to
  7962 the rewriter and classical reasoner simultaneously;
  7963 
  7964 * function uresult no longer returns theorems in "standard" format;
  7965 regain previous version by: val uresult = standard o uresult;
  7966 
  7967 
  7968 
  7969 New in Isabelle94-6
  7970 -------------------
  7971 
  7972 * oracles -- these establish an interface between Isabelle and trusted
  7973 external reasoners, which may deliver results as theorems;
  7974 
  7975 * proof objects (in particular record all uses of oracles);
  7976 
  7977 * Simp_tac, Fast_tac, etc. that refer to implicit simpset / claset;
  7978 
  7979 * "constdefs" section in theory files;
  7980 
  7981 * "primrec" section (HOL) no longer requires names;
  7982 
  7983 * internal type "tactic" now simply "thm -> thm Sequence.seq";
  7984 
  7985 
  7986 
  7987 New in Isabelle94-5
  7988 -------------------
  7989 
  7990 * reduced space requirements;
  7991 
  7992 * automatic HTML generation from theories;
  7993 
  7994 * theory files no longer require "..." (quotes) around most types;
  7995 
  7996 * new examples, including two proofs of the Church-Rosser theorem;
  7997 
  7998 * non-curried (1994) version of HOL is no longer distributed;
  7999 
  8000 
  8001 
  8002 New in Isabelle94-4
  8003 -------------------
  8004 
  8005 * greatly reduced space requirements;
  8006 
  8007 * theory files (.thy) no longer require \...\ escapes at line breaks;
  8008 
  8009 * searchable theorem database (see the section "Retrieving theorems" on
  8010 page 8 of the Reference Manual);
  8011 
  8012 * new examples, including Grabczewski's monumental case study of the
  8013 Axiom of Choice;
  8014 
  8015 * The previous version of HOL renamed to Old_HOL;
  8016 
  8017 * The new version of HOL (previously called CHOL) uses a curried syntax
  8018 for functions.  Application looks like f a b instead of f(a,b);
  8019 
  8020 * Mutually recursive inductive definitions finally work in HOL;
  8021 
  8022 * In ZF, pattern-matching on tuples is now available in all abstractions and
  8023 translates to the operator "split";
  8024 
  8025 
  8026 
  8027 New in Isabelle94-3
  8028 -------------------
  8029 
  8030 * new infix operator, addss, allowing the classical reasoner to
  8031 perform simplification at each step of its search.  Example:
  8032         fast_tac (cs addss ss)
  8033 
  8034 * a new logic, CHOL, the same as HOL, but with a curried syntax
  8035 for functions.  Application looks like f a b instead of f(a,b).  Also pairs
  8036 look like (a,b) instead of <a,b>;
  8037 
  8038 * PLEASE NOTE: CHOL will eventually replace HOL!
  8039 
  8040 * In CHOL, pattern-matching on tuples is now available in all abstractions.
  8041 It translates to the operator "split".  A new theory of integers is available;
  8042 
  8043 * In ZF, integer numerals now denote two's-complement binary integers.
  8044 Arithmetic operations can be performed by rewriting.  See ZF/ex/Bin.ML;
  8045 
  8046 * Many new examples: I/O automata, Church-Rosser theorem, equivalents
  8047 of the Axiom of Choice;
  8048 
  8049 
  8050 
  8051 New in Isabelle94-2
  8052 -------------------
  8053 
  8054 * Significantly faster resolution;
  8055 
  8056 * the different sections in a .thy file can now be mixed and repeated
  8057 freely;
  8058 
  8059 * Database of theorems for FOL, HOL and ZF.  New
  8060 commands including qed, qed_goal and bind_thm store theorems in the database.
  8061 
  8062 * Simple database queries: return a named theorem (get_thm) or all theorems of
  8063 a given theory (thms_of), or find out what theory a theorem was proved in
  8064 (theory_of_thm);
  8065 
  8066 * Bugs fixed in the inductive definition and datatype packages;
  8067 
  8068 * The classical reasoner provides deepen_tac and depth_tac, making FOL_dup_cs
  8069 and HOL_dup_cs obsolete;
  8070 
  8071 * Syntactic ambiguities caused by the new treatment of syntax in Isabelle94-1
  8072 have been removed;
  8073 
  8074 * Simpler definition of function space in ZF;
  8075 
  8076 * new results about cardinal and ordinal arithmetic in ZF;
  8077 
  8078 * 'subtype' facility in HOL for introducing new types as subsets of existing
  8079 types;
  8080 
  8081 :mode=text:wrap=hard:maxLineLen=72: