NEWS
author wenzelm
Sat, 15 Jan 2011 13:34:10 +0100
changeset 41819 19017138241c
parent 41760 8445396e1e39
child 41820 089049b768c6
permissions -rw-r--r--
misc tuning for release;
     1 Isabelle NEWS -- history user-relevant changes
     2 ==============================================
     3 
     4 New in Isabelle2011 (January 2011)
     5 ----------------------------------
     6 
     7 *** General ***
     8 
     9 * Significantly improved Isabelle/Isar implementation manual.
    10 
    11 * Source files are always encoded as UTF-8, instead of old-fashioned
    12 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
    13 the following package declarations:
    14 
    15   \usepackage[utf8]{inputenc}
    16   \usepackage{textcomp}
    17 
    18 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
    19 a Unicode character is treated as a single symbol, not a sequence of
    20 non-ASCII bytes as before.  Since Isabelle/ML string literals may
    21 contain symbols without further backslash escapes, Unicode can now be
    22 used here as well.  Recall that Symbol.explode in ML provides a
    23 consistent view on symbols, while raw explode (or String.explode)
    24 merely give a byte-oriented representation.
    25 
    26 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
    27 (and thus refers to something like $HOME/.isabelle/IsabelleXXXX),
    28 while the default heap location within that directory lacks that extra
    29 suffix.  This isolates multiple Isabelle installations from each
    30 other, avoiding problems with old settings in new versions.
    31 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
    32 
    33 * Theory loading: only the master source file is looked-up in the
    34 implicit load path, all other files are addressed relatively to its
    35 directory.  Minor INCOMPATIBILITY, subtle change in semantics.
    36 
    37 * Special treatment of ML file names has been discontinued.
    38 Historically, optional extensions .ML or .sml were added on demand --
    39 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
    40 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
    41 
    42 * Various options that affect pretty printing etc. are now properly
    43 handled within the context via configuration options, instead of
    44 unsynchronized references or print modes.  There are both ML Config.T
    45 entities and Isar declaration attributes to access these.
    46 
    47   ML (Config.T)                 Isar (attribute)
    48 
    49   eta_contract                  eta_contract
    50   show_brackets                 show_brackets
    51   show_sorts                    show_sorts
    52   show_types                    show_types
    53   show_question_marks           show_question_marks
    54   show_consts                   show_consts
    55   show_abbrevs                  show_abbrevs
    56 
    57   Syntax.ast_trace              syntax_ast_trace
    58   Syntax.ast_stat               syntax_ast_stat
    59   Syntax.ambiguity_level        syntax_ambiguity_level
    60 
    61   Goal_Display.goals_limit      goals_limit
    62   Goal_Display.show_main_goal   show_main_goal
    63 
    64   Method.rule_trace             rule_trace
    65 
    66   Thy_Output.display            thy_output_display
    67   Thy_Output.quotes             thy_output_quotes
    68   Thy_Output.indent             thy_output_indent
    69   Thy_Output.source             thy_output_source
    70   Thy_Output.break              thy_output_break
    71 
    72 Note that corresponding "..._default" references in ML may only be
    73 changed globally at the ROOT session setup, but *not* within a theory.
    74 The option "show_abbrevs" supersedes the former print mode
    75 "no_abbrevs" with inverted meaning.
    76 
    77 * More systematic naming of some configuration options.
    78 INCOMPATIBILITY.
    79 
    80   trace_simp  ~>  simp_trace
    81   debug_simp  ~>  simp_debug
    82 
    83 * Support for real valued configuration options, using simplistic
    84 floating-point notation that coincides with the inner syntax for
    85 float_token.
    86 
    87 * Theory loader: implicit load path is considered legacy.  Use
    88 explicit file specifications instead, relatively to the directory of
    89 the enclosing theory file.
    90 
    91 
    92 *** Pure ***
    93 
    94 * Command 'type_synonym' (with single argument) replaces somewhat
    95 outdated 'types', which is still available as legacy feature for some
    96 time.
    97 
    98 * Command 'nonterminal' (with 'and' separated list of arguments)
    99 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
   100 
   101 * Command 'notepad' replaces former 'example_proof' for
   102 experimentation in Isar without any result.  INCOMPATIBILITY.
   103 
   104 * Support for real valued preferences (with approximative PGIP type).
   105 
   106 * Locale interpretation commands 'interpret' and 'sublocale' accept
   107 lists of equations to map definitions in a locale to appropriate
   108 entities in the context of the interpretation.  The 'interpretation'
   109 command already provided this functionality.
   110 
   111 * New diagnostic command 'print_dependencies' prints the locale
   112 instances that would be activated if the specified expression was
   113 interpreted in the current context.  Variant 'print_dependencies!'
   114 assumes a context without interpretations.
   115 
   116 * Diagnostic command 'print_interps' prints interpretations in proofs
   117 in addition to interpretations in theories.
   118 
   119 * Discontinued obsolete 'global' and 'local' commands to manipulate
   120 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
   121 Sign.root_path and Sign.local_path may be applied directly where this
   122 feature is still required for historical reasons.
   123 
   124 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
   125 'definition' instead.
   126 
   127 * Document antiquotations @{class} and @{type} print classes and type
   128 constructors.
   129 
   130 * Document antiquotation @{file} checks file/directory entries within
   131 the local file system.
   132 
   133 
   134 *** HOL ***
   135 
   136 * Simproc "list_to_set_comprehension" rewrites list comprehensions
   137 applied to List.set to set comprehensions.  Occasional
   138 INCOMPATIBILITY, may be deactivated like this:
   139 
   140   declare [[simproc del: list_to_set_comprehension]]
   141 
   142 * Functions can be declared as coercions and type inference will add
   143 them as necessary upon input of a term. Theory Complex_Main declares
   144 real :: nat => real and real :: int => real as coercions. A coercion
   145 function f is declared like this:
   146 
   147   declare [[coercion f]]
   148 
   149 To lift coercions through type constructors (e.g. from nat => real to
   150 nat list => real list), map functions can be declared, e.g.
   151 
   152   declare [[coercion_map map]]
   153 
   154 Currently coercion inference is activated only in theories including
   155 real numbers, i.e. descendants of Complex_Main.  This is controlled by
   156 the configuration option "coercion_enabled", e.g. it can be enabled in
   157 other theories like this:
   158 
   159   declare [[coercion_enabled]]
   160 
   161 * Command 'partial_function' provides basic support for recursive
   162 function definitions over complete partial orders.  Concrete instances
   163 are provided for i) the option type, ii) tail recursion on arbitrary
   164 types, and iii) the heap monad of Imperative_HOL.  See
   165 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
   166 for examples.
   167 
   168 * Scala (2.8 or higher) has been added to the target languages of the
   169 code generator.
   170 
   171 * Inductive package: now offers command 'inductive_simps' to
   172 automatically derive instantiated and simplified equations for
   173 inductive predicates, similar to 'inductive_cases'.
   174 
   175 * Function package: f.psimps rules are no longer implicitly declared
   176 as [simp].  INCOMPATIBILITY.
   177 
   178 * Datatype package: theorems generated for executable equality (class
   179 "eq") carry proper names and are treated as default code equations.
   180 
   181 * Command 'enriched_type' allows to register properties of the
   182 functorial structure of types.
   183 
   184 * Improved infrastructure for term evaluation using code generator
   185 techniques, in particular static evaluation conversions.
   186 
   187 * Code generator: globbing constant expressions "*" and "Theory.*"
   188 have been replaced by the more idiomatic "_" and "Theory._".
   189 INCOMPATIBILITY.
   190 
   191 * Code generator: export_code without explicit file declaration prints
   192 to standard output.  INCOMPATIBILITY.
   193 
   194 * Code generator: do not print function definitions for case
   195 combinators any longer.
   196 
   197 * Simplification with rules determined by code generator with
   198 src/Tools/Code/code_simp.ML and method "code_simp".
   199 
   200 * Records: logical foundation type for records does not carry a
   201 '_type' suffix any longer (obsolete due to authentic syntax).
   202 INCOMPATIBILITY.
   203 
   204 * Code generation for records: more idiomatic representation of record
   205 types.  Warning: records are not covered by ancient SML code
   206 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
   207 rep_datatype declaration helps to succeed then:
   208 
   209   record 'a foo = ...
   210   ...
   211   rep_datatype foo_ext ...
   212 
   213 * Quickcheck now by default uses exhaustive testing instead of random
   214 testing.  Random testing can be invoked by "quickcheck [random]",
   215 exhaustive testing by "quickcheck [exhaustive]".
   216 
   217 * Quickcheck instantiates polymorphic types with small finite
   218 datatypes by default. This enables a simple execution mechanism to
   219 handle quantifiers and function equality over the finite datatypes.
   220 
   221 * Quickcheck random generator has been renamed from "code" to
   222 "random".  INCOMPATIBILITY.
   223 
   224 * Quickcheck now has a configurable time limit which is set to 30
   225 seconds by default. This can be changed by adding [timeout = n] to the
   226 quickcheck command. The time limit for Auto Quickcheck is still set
   227 independently.
   228 
   229 * Quickcheck in locales considers interpretations of that locale for
   230 counter example search.
   231 
   232 * Sledgehammer:
   233   - Added "smt" and "remote_smt" provers based on the "smt" proof
   234     method. See the Sledgehammer manual for details ("isabelle doc
   235     sledgehammer").
   236   - Renamed commands:
   237     sledgehammer atp_info ~> sledgehammer running_provers
   238     sledgehammer atp_kill ~> sledgehammer kill_provers
   239     sledgehammer available_atps ~> sledgehammer available_provers
   240     INCOMPATIBILITY.
   241   - Renamed options:
   242     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
   243     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
   244     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
   245     (and "ms" and "min" are no longer supported)
   246     INCOMPATIBILITY.
   247 
   248 * Nitpick:
   249   - Renamed options:
   250     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
   251     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
   252     INCOMPATIBILITY.
   253   - Added support for partial quotient types.
   254   - Added local versions of the "Nitpick.register_xxx" functions.
   255   - Added "whack" option.
   256   - Allow registration of quotient types as codatatypes.
   257   - Improved "merge_type_vars" option to merge more types.
   258   - Removed unsound "fast_descrs" option.
   259   - Added custom symmetry breaking for datatypes, making it possible to reach
   260     higher cardinalities.
   261   - Prevent the expansion of too large definitions.
   262 
   263 * Proof methods "metis" and "meson" now have configuration options
   264 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
   265 to diagnose these tools. E.g.
   266 
   267     using [[metis_trace = true]]
   268 
   269 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
   270 manually as command 'solve_direct'.
   271 
   272 * The default SMT solver is now CVC3.  Z3 must be enabled explicitly
   273 (due to licensing issues) via Z3_NON_COMMERCIAL in etc/settings of the
   274 component, for example.
   275 
   276 * Remote SMT solvers need to be referred to by the "remote_" prefix,
   277 i.e. "remote_cvc3" and "remote_z3".
   278 
   279 * Added basic SMT support for datatypes, records, and typedefs using
   280 the oracle mode (no proofs).  Direct support of pairs has been dropped
   281 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
   282 support for a similar behavior).  Minor INCOMPATIBILITY.
   283 
   284 * Changed SMT configuration options:
   285   - Renamed:
   286     z3_proofs ~> smt_oracle (with inverted meaning)
   287     z3_trace_assms ~> smt_trace_used_facts
   288     INCOMPATIBILITY.
   289   - Added:
   290     smt_verbose
   291     smt_random_seed
   292     smt_datatypes
   293     smt_infer_triggers
   294     smt_monomorph_limit
   295     cvc3_options
   296     remote_cvc3_options
   297     remote_z3_options
   298     yices_options
   299 
   300 * Boogie output files (.b2i files) need to be declared in the theory
   301 header.
   302 
   303 * Dropped syntax for old version of primrec package.  INCOMPATIBILITY.
   304 
   305 * Multivariate Analysis: Introduced a type class for euclidean
   306 space. Most theorems are now stated in terms of euclidean spaces
   307 instead of finite cartesian products.
   308 
   309   types
   310     real ^ 'n ~>  'a::real_vector
   311               ~>  'a::euclidean_space
   312               ~>  'a::ordered_euclidean_space
   313         (depends on your needs)
   314 
   315   constants
   316      _ $ _        ~> _ $$ _
   317      \<chi> x. _  ~> \<chi>\<chi> x. _
   318      CARD('n)     ~> DIM('a)
   319 
   320 Also note that the indices are now natural numbers and not from some
   321 finite type. Finite cartesian products of euclidean spaces, products
   322 of euclidean spaces the real and complex numbers are instantiated to
   323 be euclidean_spaces.  INCOMPATIBILITY.
   324 
   325 * Session Probability: Introduced pextreal as positive extended real
   326 numbers.  Use pextreal as value for measures.  Introduce the
   327 Radon-Nikodym derivative, product spaces and Fubini's theorem for
   328 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
   329 the integral in Multivariate Analysis.  INCOMPATIBILITY.
   330 
   331 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   332 INCOMPATIBILITY.
   333 
   334 * Theory Library/Monad_Syntax provides do-syntax for monad types.
   335 Syntax in Library/State_Monad has been changed to avoid ambiguities.
   336 INCOMPATIBILITY.
   337 
   338 * Theory SetsAndFunctions has been split into Function_Algebras and
   339 Set_Algebras; canonical names for instance definitions for functions;
   340 various improvements.  INCOMPATIBILITY.
   341 
   342 * Theory Library/Multiset provides stable quicksort implementation of
   343 sort_key.
   344 
   345 * Former theory Library/Enum is now part of the HOL-Main image.
   346 INCOMPATIBILITY: all constants of the Enum theory now have to be
   347 referred to by its qualified name.
   348 
   349   enum    ~>  Enum.enum
   350   nlists  ~>  Enum.nlists
   351   product ~>  Enum.product
   352 
   353 * Removed simplifier congruence rule of "prod_case", as has for long
   354 been the case with "split".  INCOMPATIBILITY.
   355 
   356 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
   357 
   358 * Removed [split_format ... and ... and ...] version of
   359 [split_format].  Potential INCOMPATIBILITY.
   360 
   361 * Predicate "sorted" now defined inductively, with nice induction
   362 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
   363 
   364 * Constant "contents" renamed to "the_elem", to free the generic name
   365 contents for other uses.  INCOMPATIBILITY.
   366 
   367 * Renamed class eq and constant eq (for code generation) to class
   368 equal and constant equal, plus renaming of related facts and various
   369 tuning.  INCOMPATIBILITY.
   370 
   371 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
   372 
   373 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
   374 INCOMPATIBILITY.
   375 
   376 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
   377 avoid confusion with finite sets.  INCOMPATIBILITY.
   378 
   379 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
   380 INCOMPATIBILITY.
   381 
   382 * Abandoned locales equiv, congruent and congruent2 for equivalence
   383 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
   384 for congruent(2)).
   385 
   386 * Some previously unqualified names have been qualified:
   387 
   388   types
   389     bool ~> HOL.bool
   390     nat ~> Nat.nat
   391 
   392   constants
   393     Trueprop ~> HOL.Trueprop
   394     True ~> HOL.True
   395     False ~> HOL.False
   396     op & ~> HOL.conj
   397     op | ~> HOL.disj
   398     op --> ~> HOL.implies
   399     op = ~> HOL.eq
   400     Not ~> HOL.Not
   401     The ~> HOL.The
   402     All ~> HOL.All
   403     Ex ~> HOL.Ex
   404     Ex1 ~> HOL.Ex1
   405     Let ~> HOL.Let
   406     If ~> HOL.If
   407     Ball ~> Set.Ball
   408     Bex ~> Set.Bex
   409     Suc ~> Nat.Suc
   410     Pair ~> Product_Type.Pair
   411     fst ~> Product_Type.fst
   412     snd ~> Product_Type.snd
   413     curry ~> Product_Type.curry
   414     op : ~> Set.member
   415     Collect ~> Set.Collect
   416 
   417 INCOMPATIBILITY.
   418 
   419 * More canonical naming convention for some fundamental definitions:
   420 
   421     bot_bool_eq ~> bot_bool_def
   422     top_bool_eq ~> top_bool_def
   423     inf_bool_eq ~> inf_bool_def
   424     sup_bool_eq ~> sup_bool_def
   425     bot_fun_eq  ~> bot_fun_def
   426     top_fun_eq  ~> top_fun_def
   427     inf_fun_eq  ~> inf_fun_def
   428     sup_fun_eq  ~> sup_fun_def
   429 
   430 INCOMPATIBILITY.
   431 
   432 * More stylized fact names:
   433 
   434   expand_fun_eq ~> fun_eq_iff
   435   expand_set_eq ~> set_eq_iff
   436   set_ext       ~> set_eqI
   437   nat_number    ~> eval_nat_numeral
   438 
   439 INCOMPATIBILITY.
   440 
   441 * Refactoring of code-generation specific operations in theory List:
   442 
   443   constants
   444     null ~> List.null
   445 
   446   facts
   447     mem_iff ~> member_def
   448     null_empty ~> null_def
   449 
   450 INCOMPATIBILITY.  Note that these were not supposed to be used
   451 regularly unless for striking reasons; their main purpose was code
   452 generation.
   453 
   454 Various operations from the Haskell prelude are used for generating
   455 Haskell code.
   456 
   457 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
   458 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
   459 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
   460 
   461 * Abolished some non-alphabetic type names: "prod" and "sum" replace
   462 "*" and "+" respectively.  INCOMPATIBILITY.
   463 
   464 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
   465 "Sum_Type.Plus" instead.
   466 
   467 * Constant "split" has been merged with constant "prod_case"; names of
   468 ML functions, facts etc. involving split have been retained so far,
   469 though.  INCOMPATIBILITY.
   470 
   471 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
   472 instead.  INCOMPATIBILITY.
   473 
   474 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
   475 INCOMPATIBILITY.
   476 
   477 
   478 *** HOL-Algebra ***
   479 
   480 * Theorems for additive ring operations (locale abelian_monoid and
   481 descendants) are generated by interpretation from their multiplicative
   482 counterparts.  Names (in particular theorem names) have the mandatory
   483 qualifier 'add'.  Previous theorem names are redeclared for
   484 compatibility.
   485 
   486 * Structure "int_ring" is now an abbreviation (previously a
   487 definition).  This fits more natural with advanced interpretations.
   488 
   489 
   490 *** HOLCF ***
   491 
   492 * The domain package now runs in definitional mode by default: The
   493 former command 'new_domain' is now called 'domain'.  To use the domain
   494 package in its original axiomatic mode, use 'domain (unsafe)'.
   495 INCOMPATIBILITY.
   496 
   497 * The new class "domain" is now the default sort.  Class "predomain"
   498 is an unpointed version of "domain". Theories can be updated by
   499 replacing sort annotations as shown below.  INCOMPATIBILITY.
   500 
   501   'a::type ~> 'a::countable
   502   'a::cpo  ~> 'a::predomain
   503   'a::pcpo ~> 'a::domain
   504 
   505 * The old type class "rep" has been superseded by class "domain".
   506 Accordingly, users of the definitional package must remove any
   507 "default_sort rep" declarations.  INCOMPATIBILITY.
   508 
   509 * The domain package (definitional mode) now supports unpointed
   510 predomain argument types, as long as they are marked 'lazy'. (Strict
   511 arguments must be in class "domain".) For example, the following
   512 domain definition now works:
   513 
   514   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
   515 
   516 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
   517 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
   518 'a option, and 'a list.  Additionally, it configures fixrec and the
   519 domain package to work with these types.  For example:
   520 
   521   fixrec isInl :: "('a + 'b) u -> tr"
   522     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
   523 
   524   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
   525 
   526 * The "(permissive)" option of fixrec has been replaced with a
   527 per-equation "(unchecked)" option. See
   528 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
   529 
   530 * The "bifinite" class no longer fixes a constant "approx"; the class
   531 now just asserts that such a function exists.  INCOMPATIBILITY.
   532 
   533 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
   534 defines an embedding of type 'a defl into udom by default; instances
   535 of "bifinite" and "domain" classes are available in
   536 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
   537 
   538 * The syntax "REP('a)" has been replaced with "DEFL('a)".
   539 
   540 * The predicate "directed" has been removed.  INCOMPATIBILITY.
   541 
   542 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
   543 
   544 * The function "cprod_map" has been renamed to "prod_map".
   545 INCOMPATIBILITY.
   546 
   547 * The monadic bind operator on each powerdomain has new binder syntax
   548 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
   549 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
   550 
   551 * The infix syntax for binary union on each powerdomain has changed
   552 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
   553 syntax.  INCOMPATIBILITY.
   554 
   555 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
   556 still supported as an input translation.
   557 
   558 * Renamed some theorems (the original names are also still available).
   559 
   560   expand_fun_below   ~> fun_below_iff
   561   below_fun_ext      ~> fun_belowI
   562   expand_cfun_eq     ~> cfun_eq_iff
   563   ext_cfun           ~> cfun_eqI
   564   expand_cfun_below  ~> cfun_below_iff
   565   below_cfun_ext     ~> cfun_belowI
   566   cont2cont_Rep_CFun ~> cont2cont_APP
   567 
   568 * The Abs and Rep functions for various types have changed names.
   569 Related theorem names have also changed to match. INCOMPATIBILITY.
   570 
   571   Rep_CFun  ~> Rep_cfun
   572   Abs_CFun  ~> Abs_cfun
   573   Rep_Sprod ~> Rep_sprod
   574   Abs_Sprod ~> Abs_sprod
   575   Rep_Ssum  ~> Rep_ssum
   576   Abs_Ssum  ~> Abs_ssum
   577 
   578 * Lemmas with names of the form *_defined_iff or *_strict_iff have
   579 been renamed to *_bottom_iff.  INCOMPATIBILITY.
   580 
   581 * Various changes to bisimulation/coinduction with domain package:
   582 
   583   - Definitions of "bisim" constants no longer mention definedness.
   584   - With mutual recursion, "bisim" predicate is now curried.
   585   - With mutual recursion, each type gets a separate coind theorem.
   586   - Variable names in bisim_def and coinduct rules have changed.
   587 
   588 INCOMPATIBILITY.
   589 
   590 * Case combinators generated by the domain package for type "foo" are
   591 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
   592 
   593 * Several theorems have been renamed to more accurately reflect the
   594 names of constants and types involved.  INCOMPATIBILITY.
   595 
   596   thelub_const    ~> lub_const
   597   lub_const       ~> is_lub_const
   598   thelubI         ~> lub_eqI
   599   is_lub_lub      ~> is_lubD2
   600   lubI            ~> is_lub_lub
   601   unique_lub      ~> is_lub_unique
   602   is_ub_lub       ~> is_lub_rangeD1
   603   lub_bin_chain   ~> is_lub_bin_chain
   604   lub_fun         ~> is_lub_fun
   605   thelub_fun      ~> lub_fun
   606   thelub_cfun     ~> lub_cfun
   607   thelub_Pair     ~> lub_Pair
   608   lub_cprod       ~> is_lub_prod
   609   thelub_cprod    ~> lub_prod
   610   minimal_cprod   ~> minimal_prod
   611   inst_cprod_pcpo ~> inst_prod_pcpo
   612   UU_I            ~> bottomI
   613   compact_UU      ~> compact_bottom
   614   deflation_UU    ~> deflation_bottom
   615   finite_deflation_UU ~> finite_deflation_bottom
   616 
   617 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
   618 
   619   sq_ord_less_eq_trans ~> below_eq_trans
   620   sq_ord_eq_less_trans ~> eq_below_trans
   621   refl_less            ~> below_refl
   622   trans_less           ~> below_trans
   623   antisym_less         ~> below_antisym
   624   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
   625   box_less             ~> box_below
   626   rev_trans_less       ~> rev_below_trans
   627   not_less2not_eq      ~> not_below2not_eq
   628   less_UU_iff          ~> below_UU_iff
   629   flat_less_iff        ~> flat_below_iff
   630   adm_less             ~> adm_below
   631   adm_not_less         ~> adm_not_below
   632   adm_compact_not_less ~> adm_compact_not_below
   633   less_fun_def         ~> below_fun_def
   634   expand_fun_less      ~> fun_below_iff
   635   less_fun_ext         ~> fun_belowI
   636   less_discr_def       ~> below_discr_def
   637   discr_less_eq        ~> discr_below_eq
   638   less_unit_def        ~> below_unit_def
   639   less_cprod_def       ~> below_prod_def
   640   prod_lessI           ~> prod_belowI
   641   Pair_less_iff        ~> Pair_below_iff
   642   fst_less_iff         ~> fst_below_iff
   643   snd_less_iff         ~> snd_below_iff
   644   expand_cfun_less     ~> cfun_below_iff
   645   less_cfun_ext        ~> cfun_belowI
   646   injection_less       ~> injection_below
   647   less_up_def          ~> below_up_def
   648   not_Iup_less         ~> not_Iup_below
   649   Iup_less             ~> Iup_below
   650   up_less              ~> up_below
   651   Def_inject_less_eq   ~> Def_below_Def
   652   Def_less_is_eq       ~> Def_below_iff
   653   spair_less_iff       ~> spair_below_iff
   654   less_sprod           ~> below_sprod
   655   spair_less           ~> spair_below
   656   sfst_less_iff        ~> sfst_below_iff
   657   ssnd_less_iff        ~> ssnd_below_iff
   658   fix_least_less       ~> fix_least_below
   659   dist_less_one        ~> dist_below_one
   660   less_ONE             ~> below_ONE
   661   ONE_less_iff         ~> ONE_below_iff
   662   less_sinlD           ~> below_sinlD
   663   less_sinrD           ~> below_sinrD
   664 
   665 
   666 *** FOL and ZF ***
   667 
   668 * All constant names are now qualified internally and use proper
   669 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
   670 
   671 
   672 *** ML ***
   673 
   674 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
   675 main functionality is provided by structure Simplifier.
   676 
   677 * Syntax.pretty_priority (default 0) configures the required priority
   678 of pretty-printed output and thus affects insertion of parentheses.
   679 
   680 * Syntax.default_root (default "any") configures the inner syntax
   681 category (nonterminal symbol) for parsing of terms.
   682 
   683 * Former exception Library.UnequalLengths now coincides with
   684 ListPair.UnequalLengths.
   685 
   686 * Renamed raw "explode" function to "raw_explode" to emphasize its
   687 meaning.  Note that internally to Isabelle, Symbol.explode is used in
   688 almost all situations.
   689 
   690 * Discontinued obsolete function sys_error and exception SYS_ERROR.
   691 See implementation manual for further details on exceptions in
   692 Isabelle/ML.
   693 
   694 * Antiquotation @{assert} inlines a function bool -> unit that raises
   695 Fail if the argument is false.  Due to inlining the source position of
   696 failed assertions is included in the error output.
   697 
   698 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
   699 text is in practice always evaluated with a stable theory checkpoint.
   700 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
   701 
   702 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
   703 meaning.
   704 
   705 * Renamed structure PureThy to Pure_Thy and moved most of its
   706 operations to structure Global_Theory, to emphasize that this is
   707 rarely-used global-only stuff.
   708 
   709 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
   710 instead (or tracing for high-volume output).
   711 
   712 * Configuration option show_question_marks only affects regular pretty
   713 printing of types and terms, not raw Term.string_of_vname.
   714 
   715 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
   716 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
   717 @{thms} for most purposes.
   718 
   719 * ML structure Unsynchronized never opened, not even in Isar
   720 interaction mode as before.  Old Unsynchronized.set etc. have been
   721 discontinued -- use plain := instead.  This should be *rare* anyway,
   722 since modern tools always work via official context data, notably
   723 configuration options.
   724 
   725 * ML antiquotations @{theory} and @{theory_ref} refer to named
   726 theories from the ancestry of the current context, not any accidental
   727 theory loader state as before.  Potential INCOMPATIBILITY, subtle
   728 change in semantics.
   729 
   730 * Parallel and asynchronous execution requires special care concerning
   731 interrupts.  Structure Exn provides some convenience functions that
   732 avoid working directly with raw Interrupt.  User code must not absorb
   733 interrupts -- intermediate handling (for cleanup etc.) needs to be
   734 followed by re-raising of the original exception.  Another common
   735 source of mistakes are "handle _" patterns, which make the meaning of
   736 the program subject to physical effects of the environment.
   737 
   738 
   739 *** System ***
   740 
   741 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
   742 DejaVu Sans.
   743 
   744 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   745 
   746 
   747 
   748 New in Isabelle2009-2 (June 2010)
   749 ---------------------------------
   750 
   751 *** General ***
   752 
   753 * Authentic syntax for *all* logical entities (type classes, type
   754 constructors, term constants): provides simple and robust
   755 correspondence between formal entities and concrete syntax.  Within
   756 the parse tree / AST representations, "constants" are decorated by
   757 their category (class, type, const) and spelled out explicitly with
   758 their full internal name.
   759 
   760 Substantial INCOMPATIBILITY concerning low-level syntax declarations
   761 and translations (translation rules and translation functions in ML).
   762 Some hints on upgrading:
   763 
   764   - Many existing uses of 'syntax' and 'translations' can be replaced
   765     by more modern 'type_notation', 'notation' and 'abbreviation',
   766     which are independent of this issue.
   767 
   768   - 'translations' require markup within the AST; the term syntax
   769     provides the following special forms:
   770 
   771       CONST c   -- produces syntax version of constant c from context
   772       XCONST c  -- literally c, checked as constant from context
   773       c         -- literally c, if declared by 'syntax'
   774 
   775     Plain identifiers are treated as AST variables -- occasionally the
   776     system indicates accidental variables via the error "rhs contains
   777     extra variables".
   778 
   779     Type classes and type constructors are marked according to their
   780     concrete syntax.  Some old translations rules need to be written
   781     for the "type" category, using type constructor application
   782     instead of pseudo-term application of the default category
   783     "logic".
   784 
   785   - 'parse_translation' etc. in ML may use the following
   786     antiquotations:
   787 
   788       @{class_syntax c}   -- type class c within parse tree / AST
   789       @{term_syntax c}    -- type constructor c within parse tree / AST
   790       @{const_syntax c}   -- ML version of "CONST c" above
   791       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
   792 
   793   - Literal types within 'typed_print_translations', i.e. those *not*
   794     represented as pseudo-terms are represented verbatim.  Use @{class
   795     c} or @{type_name c} here instead of the above syntax
   796     antiquotations.
   797 
   798 Note that old non-authentic syntax was based on unqualified base
   799 names, so all of the above "constant" names would coincide.  Recall
   800 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
   801 diagnose syntax problems.
   802 
   803 * Type constructors admit general mixfix syntax, not just infix.
   804 
   805 * Concrete syntax may be attached to local entities without a proof
   806 body, too.  This works via regular mixfix annotations for 'fix',
   807 'def', 'obtain' etc. or via the explicit 'write' command, which is
   808 similar to the 'notation' command in theory specifications.
   809 
   810 * Discontinued unnamed infix syntax (legacy feature for many years) --
   811 need to specify constant name and syntax separately.  Internal ML
   812 datatype constructors have been renamed from InfixName to Infix etc.
   813 Minor INCOMPATIBILITY.
   814 
   815 * Schematic theorem statements need to be explicitly markup as such,
   816 via commands 'schematic_lemma', 'schematic_theorem',
   817 'schematic_corollary'.  Thus the relevance of the proof is made
   818 syntactically clear, which impacts performance in a parallel or
   819 asynchronous interactive environment.  Minor INCOMPATIBILITY.
   820 
   821 * Use of cumulative prems via "!" in some proof methods has been
   822 discontinued (old legacy feature).
   823 
   824 * References 'trace_simp' and 'debug_simp' have been replaced by
   825 configuration options stored in the context. Enabling tracing (the
   826 case of debugging is similar) in proofs works via
   827 
   828   using [[trace_simp = true]]
   829 
   830 Tracing is then active for all invocations of the simplifier in
   831 subsequent goal refinement steps. Tracing may also still be enabled or
   832 disabled via the ProofGeneral settings menu.
   833 
   834 * Separate commands 'hide_class', 'hide_type', 'hide_const',
   835 'hide_fact' replace the former 'hide' KIND command.  Minor
   836 INCOMPATIBILITY.
   837 
   838 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
   839 more efficient than combinations with -q1 or -q2.
   840 
   841 
   842 *** Pure ***
   843 
   844 * Proofterms record type-class reasoning explicitly, using the
   845 "unconstrain" operation internally.  This eliminates all sort
   846 constraints from a theorem and proof, introducing explicit
   847 OFCLASS-premises.  On the proof term level, this operation is
   848 automatically applied at theorem boundaries, such that closed proofs
   849 are always free of sort constraints.  INCOMPATIBILITY for tools that
   850 inspect proof terms.
   851 
   852 * Local theory specifications may depend on extra type variables that
   853 are not present in the result type -- arguments TYPE('a) :: 'a itself
   854 are added internally.  For example:
   855 
   856   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
   857 
   858 * Predicates of locales introduced by classes carry a mandatory
   859 "class" prefix.  INCOMPATIBILITY.
   860 
   861 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
   862 
   863 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
   864 'class' instead.
   865 
   866 * Command 'code_reflect' allows to incorporate generated ML code into
   867 runtime environment; replaces immature code_datatype antiquotation.
   868 INCOMPATIBILITY.
   869 
   870 * Code generator: simple concept for abstract datatypes obeying
   871 invariants.
   872 
   873 * Code generator: details of internal data cache have no impact on the
   874 user space functionality any longer.
   875 
   876 * Methods "unfold_locales" and "intro_locales" ignore non-locale
   877 subgoals.  This is more appropriate for interpretations with 'where'.
   878 INCOMPATIBILITY.
   879 
   880 * Command 'example_proof' opens an empty proof body.  This allows to
   881 experiment with Isar, without producing any persistent result.
   882 
   883 * Commands 'type_notation' and 'no_type_notation' declare type syntax
   884 within a local theory context, with explicit checking of the
   885 constructors involved (in contrast to the raw 'syntax' versions).
   886 
   887 * Commands 'types' and 'typedecl' now work within a local theory
   888 context -- without introducing dependencies on parameters or
   889 assumptions, which is not possible in Isabelle/Pure.
   890 
   891 * Command 'defaultsort' has been renamed to 'default_sort', it works
   892 within a local theory context.  Minor INCOMPATIBILITY.
   893 
   894 
   895 *** HOL ***
   896 
   897 * Command 'typedef' now works within a local theory context -- without
   898 introducing dependencies on parameters or assumptions, which is not
   899 possible in Isabelle/Pure/HOL.  Note that the logical environment may
   900 contain multiple interpretations of local typedefs (with different
   901 non-emptiness proofs), even in a global theory context.
   902 
   903 * New package for quotient types.  Commands 'quotient_type' and
   904 'quotient_definition' may be used for defining types and constants by
   905 quotient constructions.  An example is the type of integers created by
   906 quotienting pairs of natural numbers:
   907 
   908   fun
   909     intrel :: "(nat * nat) => (nat * nat) => bool"
   910   where
   911     "intrel (x, y) (u, v) = (x + v = u + y)"
   912 
   913   quotient_type int = "nat * nat" / intrel
   914     by (auto simp add: equivp_def expand_fun_eq)
   915 
   916   quotient_definition
   917     "0::int" is "(0::nat, 0::nat)"
   918 
   919 The method "lifting" can be used to lift of theorems from the
   920 underlying "raw" type to the quotient type.  The example
   921 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
   922 construction and provides a reasoning infrastructure for finite sets.
   923 
   924 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
   925 clash with new theory Quotient in Main HOL.
   926 
   927 * Moved the SMT binding into the main HOL session, eliminating
   928 separate HOL-SMT session.
   929 
   930 * List membership infix mem operation is only an input abbreviation.
   931 INCOMPATIBILITY.
   932 
   933 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
   934 for future developements; former Library/Word.thy is still present in
   935 the AFP entry RSAPPS.
   936 
   937 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
   938 longer shadowed.  INCOMPATIBILITY.
   939 
   940 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
   941 INCOMPATIBILITY.
   942 
   943 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
   944 INCOMPATIBILITY.
   945 
   946 * Dropped normalizing_semiring etc; use the facts in semiring classes
   947 instead.  INCOMPATIBILITY.
   948 
   949 * Dropped several real-specific versions of lemmas about floor and
   950 ceiling; use the generic lemmas from theory "Archimedean_Field"
   951 instead.  INCOMPATIBILITY.
   952 
   953   floor_number_of_eq         ~> floor_number_of
   954   le_floor_eq_number_of      ~> number_of_le_floor
   955   le_floor_eq_zero           ~> zero_le_floor
   956   le_floor_eq_one            ~> one_le_floor
   957   floor_less_eq_number_of    ~> floor_less_number_of
   958   floor_less_eq_zero         ~> floor_less_zero
   959   floor_less_eq_one          ~> floor_less_one
   960   less_floor_eq_number_of    ~> number_of_less_floor
   961   less_floor_eq_zero         ~> zero_less_floor
   962   less_floor_eq_one          ~> one_less_floor
   963   floor_le_eq_number_of      ~> floor_le_number_of
   964   floor_le_eq_zero           ~> floor_le_zero
   965   floor_le_eq_one            ~> floor_le_one
   966   floor_subtract_number_of   ~> floor_diff_number_of
   967   floor_subtract_one         ~> floor_diff_one
   968   ceiling_number_of_eq       ~> ceiling_number_of
   969   ceiling_le_eq_number_of    ~> ceiling_le_number_of
   970   ceiling_le_zero_eq         ~> ceiling_le_zero
   971   ceiling_le_eq_one          ~> ceiling_le_one
   972   less_ceiling_eq_number_of  ~> number_of_less_ceiling
   973   less_ceiling_eq_zero       ~> zero_less_ceiling
   974   less_ceiling_eq_one        ~> one_less_ceiling
   975   ceiling_less_eq_number_of  ~> ceiling_less_number_of
   976   ceiling_less_eq_zero       ~> ceiling_less_zero
   977   ceiling_less_eq_one        ~> ceiling_less_one
   978   le_ceiling_eq_number_of    ~> number_of_le_ceiling
   979   le_ceiling_eq_zero         ~> zero_le_ceiling
   980   le_ceiling_eq_one          ~> one_le_ceiling
   981   ceiling_subtract_number_of ~> ceiling_diff_number_of
   982   ceiling_subtract_one       ~> ceiling_diff_one
   983 
   984 * Theory "Finite_Set": various folding_XXX locales facilitate the
   985 application of the various fold combinators on finite sets.
   986 
   987 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
   988 provides abstract red-black tree type which is backed by "RBT_Impl" as
   989 implementation.  INCOMPATIBILTY.
   990 
   991 * Theory Library/Coinductive_List has been removed -- superseded by
   992 AFP/thys/Coinductive.
   993 
   994 * Theory PReal, including the type "preal" and related operations, has
   995 been removed.  INCOMPATIBILITY.
   996 
   997 * Real: new development using Cauchy Sequences.
   998 
   999 * Split off theory "Big_Operators" containing setsum, setprod,
  1000 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  1001 
  1002 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  1003 "Int" etc.  INCOMPATIBILITY.
  1004 
  1005 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  1006 
  1007 * New set of rules "ac_simps" provides combined assoc / commute
  1008 rewrites for all interpretations of the appropriate generic locales.
  1009 
  1010 * Renamed theory "OrderedGroup" to "Groups" and split theory
  1011 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  1012 appropriate and more consistent names suitable for name prefixes
  1013 within the HOL theories.  INCOMPATIBILITY.
  1014 
  1015 * Some generic constants have been put to appropriate theories:
  1016   - less_eq, less: Orderings
  1017   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  1018   - inverse, divide: Rings
  1019 INCOMPATIBILITY.
  1020 
  1021 * More consistent naming of type classes involving orderings (and
  1022 lattices):
  1023 
  1024     lower_semilattice                   ~> semilattice_inf
  1025     upper_semilattice                   ~> semilattice_sup
  1026 
  1027     dense_linear_order                  ~> dense_linorder
  1028 
  1029     pordered_ab_group_add               ~> ordered_ab_group_add
  1030     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  1031     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  1032     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  1033     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  1034     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  1035     pordered_cancel_semiring            ~> ordered_cancel_semiring
  1036     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  1037     pordered_comm_ring                  ~> ordered_comm_ring
  1038     pordered_comm_semiring              ~> ordered_comm_semiring
  1039     pordered_ring                       ~> ordered_ring
  1040     pordered_ring_abs                   ~> ordered_ring_abs
  1041     pordered_semiring                   ~> ordered_semiring
  1042 
  1043     ordered_ab_group_add                ~> linordered_ab_group_add
  1044     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  1045     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  1046     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  1047     ordered_field                       ~> linordered_field
  1048     ordered_field_no_lb                 ~> linordered_field_no_lb
  1049     ordered_field_no_ub                 ~> linordered_field_no_ub
  1050     ordered_field_dense_linear_order    ~> dense_linordered_field
  1051     ordered_idom                        ~> linordered_idom
  1052     ordered_ring                        ~> linordered_ring
  1053     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  1054     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  1055     ordered_ring_strict                 ~> linordered_ring_strict
  1056     ordered_semidom                     ~> linordered_semidom
  1057     ordered_semiring                    ~> linordered_semiring
  1058     ordered_semiring_1                  ~> linordered_semiring_1
  1059     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  1060     ordered_semiring_strict             ~> linordered_semiring_strict
  1061 
  1062   The following slightly odd type classes have been moved to a
  1063   separate theory Library/Lattice_Algebras:
  1064 
  1065     lordered_ab_group_add               ~> lattice_ab_group_add
  1066     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  1067     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  1068     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  1069     lordered_ring                       ~> lattice_ring
  1070 
  1071 INCOMPATIBILITY.
  1072 
  1073 * Refined field classes:
  1074   - classes division_ring_inverse_zero, field_inverse_zero,
  1075     linordered_field_inverse_zero include rule inverse 0 = 0 --
  1076     subsumes former division_by_zero class;
  1077   - numerous lemmas have been ported from field to division_ring.
  1078 INCOMPATIBILITY.
  1079 
  1080 * Refined algebra theorem collections:
  1081   - dropped theorem group group_simps, use algebra_simps instead;
  1082   - dropped theorem group ring_simps, use field_simps instead;
  1083   - proper theorem collection field_simps subsumes former theorem
  1084     groups field_eq_simps and field_simps;
  1085   - dropped lemma eq_minus_self_iff which is a duplicate for
  1086     equal_neg_zero.
  1087 INCOMPATIBILITY.
  1088 
  1089 * Theory Finite_Set and List: some lemmas have been generalized from
  1090 sets to lattices:
  1091 
  1092   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  1093   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  1094   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  1095   union_Union_fold_union        ~> sup_Sup_fold_sup
  1096   Inter_fold_inter              ~> Inf_fold_inf
  1097   Union_fold_union              ~> Sup_fold_sup
  1098   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  1099   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  1100   INTER_fold_inter              ~> INFI_fold_inf
  1101   UNION_fold_union              ~> SUPR_fold_sup
  1102 
  1103 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  1104 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  1105 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  1106 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  1107 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  1108 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  1109 
  1110 * Reorganized theory Multiset: swapped notation of pointwise and
  1111 multiset order:
  1112 
  1113   - pointwise ordering is instance of class order with standard syntax
  1114     <= and <;
  1115   - multiset ordering has syntax <=# and <#; partial order properties
  1116     are provided by means of interpretation with prefix
  1117     multiset_order;
  1118   - less duplication, less historical organization of sections,
  1119     conversion from associations lists to multisets, rudimentary code
  1120     generation;
  1121   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  1122     if needed.
  1123 
  1124 Renamed:
  1125 
  1126   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  1127   multi_count_ext  ~>  multiset_ext
  1128   diff_union_inverse2  ~>  diff_union_cancelR
  1129 
  1130 INCOMPATIBILITY.
  1131 
  1132 * Theory Permutation: replaced local "remove" by List.remove1.
  1133 
  1134 * Code generation: ML and OCaml code is decorated with signatures.
  1135 
  1136 * Theory List: added transpose.
  1137 
  1138 * Library/Nat_Bijection.thy is a collection of bijective functions
  1139 between nat and other types, which supersedes the older libraries
  1140 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  1141 
  1142   Constants:
  1143   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  1144   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  1145   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  1146   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  1147   Countable.pair_encode           ~> prod_encode
  1148   NatIso.prod2nat                 ~> prod_encode
  1149   NatIso.nat2prod                 ~> prod_decode
  1150   NatIso.sum2nat                  ~> sum_encode
  1151   NatIso.nat2sum                  ~> sum_decode
  1152   NatIso.list2nat                 ~> list_encode
  1153   NatIso.nat2list                 ~> list_decode
  1154   NatIso.set2nat                  ~> set_encode
  1155   NatIso.nat2set                  ~> set_decode
  1156 
  1157   Lemmas:
  1158   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  1159   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  1160   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  1161   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  1162   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  1163   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  1164   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  1165   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  1166   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  1167   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  1168   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  1169   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  1170   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  1171 
  1172 * Sledgehammer:
  1173   - Renamed ATP commands:
  1174     atp_info     ~> sledgehammer running_atps
  1175     atp_kill     ~> sledgehammer kill_atps
  1176     atp_messages ~> sledgehammer messages
  1177     atp_minimize ~> sledgehammer minimize
  1178     print_atps   ~> sledgehammer available_atps
  1179     INCOMPATIBILITY.
  1180   - Added user's manual ("isabelle doc sledgehammer").
  1181   - Added option syntax and "sledgehammer_params" to customize
  1182     Sledgehammer's behavior.  See the manual for details.
  1183   - Modified the Isar proof reconstruction code so that it produces
  1184     direct proofs rather than proofs by contradiction.  (This feature
  1185     is still experimental.)
  1186   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  1187     full-typed mode.
  1188   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  1189 
  1190 * Nitpick:
  1191   - Added and implemented "binary_ints" and "bits" options.
  1192   - Added "std" option and implemented support for nonstandard models.
  1193   - Added and implemented "finitize" option to improve the precision
  1194     of infinite datatypes based on a monotonicity analysis.
  1195   - Added support for quotient types.
  1196   - Added support for "specification" and "ax_specification"
  1197     constructs.
  1198   - Added support for local definitions (for "function" and
  1199     "termination" proofs).
  1200   - Added support for term postprocessors.
  1201   - Optimized "Multiset.multiset" and "FinFun.finfun".
  1202   - Improved efficiency of "destroy_constrs" optimization.
  1203   - Fixed soundness bugs related to "destroy_constrs" optimization and
  1204     record getters.
  1205   - Fixed soundness bug related to higher-order constructors.
  1206   - Fixed soundness bug when "full_descrs" is enabled.
  1207   - Improved precision of set constructs.
  1208   - Added "atoms" option.
  1209   - Added cache to speed up repeated Kodkod invocations on the same
  1210     problems.
  1211   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  1212     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  1213     "SAT4J_Light".  INCOMPATIBILITY.
  1214   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  1215     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  1216   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  1217 
  1218 * Method "induct" now takes instantiations of the form t, where t is not
  1219   a variable, as a shorthand for "x == t", where x is a fresh variable.
  1220   If this is not intended, t has to be enclosed in parentheses.
  1221   By default, the equalities generated by definitional instantiations
  1222   are pre-simplified, which may cause parameters of inductive cases
  1223   to disappear, or may even delete some of the inductive cases.
  1224   Use "induct (no_simp)" instead of "induct" to restore the old
  1225   behaviour. The (no_simp) option is also understood by the "cases"
  1226   and "nominal_induct" methods, which now perform pre-simplification, too.
  1227   INCOMPATIBILITY.
  1228 
  1229 
  1230 *** HOLCF ***
  1231 
  1232 * Variable names in lemmas generated by the domain package have
  1233 changed; the naming scheme is now consistent with the HOL datatype
  1234 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  1235 
  1236 * The domain package no longer defines the function "foo_copy" for
  1237 recursive domain "foo".  The reach lemma is now stated directly in
  1238 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  1239 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  1240 
  1241 * Most definedness lemmas generated by the domain package (previously
  1242 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  1243 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  1244 Proofs that used definedness lemmas as intro rules may break,
  1245 potential INCOMPATIBILITY.
  1246 
  1247 * Induction and casedist rules generated by the domain package now
  1248 declare proper case_names (one called "bottom", and one named for each
  1249 constructor).  INCOMPATIBILITY.
  1250 
  1251 * For mutually-recursive domains, separate "reach" and "take_lemma"
  1252 rules are generated for each domain, INCOMPATIBILITY.
  1253 
  1254   foo_bar.reach       ~> foo.reach  bar.reach
  1255   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  1256 
  1257 * Some lemmas generated by the domain package have been renamed for
  1258 consistency with the datatype package, INCOMPATIBILITY.
  1259 
  1260   foo.ind        ~> foo.induct
  1261   foo.finite_ind ~> foo.finite_induct
  1262   foo.coind      ~> foo.coinduct
  1263   foo.casedist   ~> foo.exhaust
  1264   foo.exhaust    ~> foo.nchotomy
  1265 
  1266 * For consistency with other definition packages, the fixrec package
  1267 now generates qualified theorem names, INCOMPATIBILITY.
  1268 
  1269   foo_simps  ~> foo.simps
  1270   foo_unfold ~> foo.unfold
  1271   foo_induct ~> foo.induct
  1272 
  1273 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  1274 method and internal fixrec proofs now use the default simpset instead.
  1275 INCOMPATIBILITY.
  1276 
  1277 * The "contlub" predicate has been removed.  Proof scripts should use
  1278 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  1279 
  1280 * The "admw" predicate has been removed, INCOMPATIBILITY.
  1281 
  1282 * The constants cpair, cfst, and csnd have been removed in favor of
  1283 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  1284 
  1285 
  1286 *** ML ***
  1287 
  1288 * Antiquotations for basic formal entities:
  1289 
  1290     @{class NAME}         -- type class
  1291     @{class_syntax NAME}  -- syntax representation of the above
  1292 
  1293     @{type_name NAME}     -- logical type
  1294     @{type_abbrev NAME}   -- type abbreviation
  1295     @{nonterminal NAME}   -- type of concrete syntactic category
  1296     @{type_syntax NAME}   -- syntax representation of any of the above
  1297 
  1298     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  1299     @{const_abbrev NAME}  -- abbreviated constant
  1300     @{const_syntax NAME}  -- syntax representation of any of the above
  1301 
  1302 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  1303 syntax constant (cf. 'syntax' command).
  1304 
  1305 * Antiquotation @{make_string} inlines a function to print arbitrary
  1306 values similar to the ML toplevel.  The result is compiler dependent
  1307 and may fall back on "?" in certain situations.
  1308 
  1309 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  1310 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  1311 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  1312 not work with the asynchronous Isar document model.
  1313 
  1314 * Configuration options now admit dynamic default values, depending on
  1315 the context or even global references.
  1316 
  1317 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  1318 uses an efficient external library if available (for Poly/ML).
  1319 
  1320 * Renamed some important ML structures, while keeping the old names
  1321 for some time as aliases within the structure Legacy:
  1322 
  1323   OuterKeyword  ~>  Keyword
  1324   OuterLex      ~>  Token
  1325   OuterParse    ~>  Parse
  1326   OuterSyntax   ~>  Outer_Syntax
  1327   PrintMode     ~>  Print_Mode
  1328   SpecParse     ~>  Parse_Spec
  1329   ThyInfo       ~>  Thy_Info
  1330   ThyLoad       ~>  Thy_Load
  1331   ThyOutput     ~>  Thy_Output
  1332   TypeInfer     ~>  Type_Infer
  1333 
  1334 Note that "open Legacy" simplifies porting of sources, but forgetting
  1335 to remove it again will complicate porting again in the future.
  1336 
  1337 * Most operations that refer to a global context are named
  1338 accordingly, e.g. Simplifier.global_context or
  1339 ProofContext.init_global.  There are some situations where a global
  1340 context actually works, but under normal circumstances one needs to
  1341 pass the proper local context through the code!
  1342 
  1343 * Discontinued old TheoryDataFun with its copy/init operation -- data
  1344 needs to be pure.  Functor Theory_Data_PP retains the traditional
  1345 Pretty.pp argument to merge, which is absent in the standard
  1346 Theory_Data version.
  1347 
  1348 * Sorts.certify_sort and derived "cert" operations for types and terms
  1349 no longer minimize sorts.  Thus certification at the boundary of the
  1350 inference kernel becomes invariant under addition of class relations,
  1351 which is an important monotonicity principle.  Sorts are now minimized
  1352 in the syntax layer only, at the boundary between the end-user and the
  1353 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  1354 explicitly in rare situations.
  1355 
  1356 * Renamed old-style Drule.standard to Drule.export_without_context, to
  1357 emphasize that this is in no way a standard operation.
  1358 INCOMPATIBILITY.
  1359 
  1360 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  1361 usual for resolution.  Rare INCOMPATIBILITY.
  1362 
  1363 * Renamed varify/unvarify operations to varify_global/unvarify_global
  1364 to emphasize that these only work in a global situation (which is
  1365 quite rare).
  1366 
  1367 * Curried take and drop in library.ML; negative length is interpreted
  1368 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  1369 
  1370 * Proof terms: type substitutions on proof constants now use canonical
  1371 order of type variables.  INCOMPATIBILITY for tools working with proof
  1372 terms.
  1373 
  1374 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  1375 may no longer carry premises.  User-level specifications are
  1376 transformed accordingly by Thm.add_axiom/add_def.
  1377 
  1378 
  1379 *** System ***
  1380 
  1381 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  1382 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  1383 proof terms are enabled unconditionally in the new HOL-Proofs image.
  1384 
  1385 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  1386 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  1387 respectively.
  1388 
  1389 * Old lib/scripts/polyml-platform is superseded by the
  1390 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  1391 variant, even on a 64 bit machine.  The following example setting
  1392 prefers 64 bit if available:
  1393 
  1394   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  1395 
  1396 * The preliminary Isabelle/jEdit application demonstrates the emerging
  1397 Isabelle/Scala layer for advanced prover interaction and integration.
  1398 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  1399 component.
  1400 
  1401 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  1402 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  1403 similar to the default assignment of the document preparation system
  1404 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  1405 provides some operations for direct access to the font without asking
  1406 the user for manual installation.
  1407 
  1408 
  1409 
  1410 New in Isabelle2009-1 (December 2009)
  1411 -------------------------------------
  1412 
  1413 *** General ***
  1414 
  1415 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  1416 one backslash should be used, even in ML sources.
  1417 
  1418 
  1419 *** Pure ***
  1420 
  1421 * Locale interpretation propagates mixins along the locale hierarchy.
  1422 The currently only available mixins are the equations used to map
  1423 local definitions to terms of the target domain of an interpretation.
  1424 
  1425 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  1426 loc" to print all interpretations of locale "loc" in the theory.
  1427 Interpretations in proofs are not shown.
  1428 
  1429 * Thoroughly revised locales tutorial.  New section on conditional
  1430 interpretation.
  1431 
  1432 * On instantiation of classes, remaining undefined class parameters
  1433 are formally declared.  INCOMPATIBILITY.
  1434 
  1435 
  1436 *** Document preparation ***
  1437 
  1438 * New generalized style concept for printing terms: @{foo (style) ...}
  1439 instead of @{foo_style style ...}  (old form is still retained for
  1440 backward compatibility).  Styles can be also applied for
  1441 antiquotations prop, term_type and typeof.
  1442 
  1443 
  1444 *** HOL ***
  1445 
  1446 * New proof method "smt" for a combination of first-order logic with
  1447 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  1448 fixed-size bitvectors; there is also basic support for higher-order
  1449 features (esp. lambda abstractions).  It is an incomplete decision
  1450 procedure based on external SMT solvers using the oracle mechanism;
  1451 for the SMT solver Z3, this method is proof-producing.  Certificates
  1452 are provided to avoid calling the external solvers solely for
  1453 re-checking proofs.  Due to a remote SMT service there is no need for
  1454 installing SMT solvers locally.  See src/HOL/SMT.
  1455 
  1456 * New commands to load and prove verification conditions generated by
  1457 the Boogie program verifier or derived systems (e.g. the Verifying C
  1458 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1459 
  1460 * New counterexample generator tool 'nitpick' based on the Kodkod
  1461 relational model finder.  See src/HOL/Tools/Nitpick and
  1462 src/HOL/Nitpick_Examples.
  1463 
  1464 * New commands 'code_pred' and 'values' to invoke the predicate
  1465 compiler and to enumerate values of inductive predicates.
  1466 
  1467 * A tabled implementation of the reflexive transitive closure.
  1468 
  1469 * New implementation of quickcheck uses generic code generator;
  1470 default generators are provided for all suitable HOL types, records
  1471 and datatypes.  Old quickcheck can be re-activated importing theory
  1472 Library/SML_Quickcheck.
  1473 
  1474 * New testing tool Mirabelle for automated proof tools.  Applies
  1475 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1476 every proof step in a theory.  To be used in batch mode via the
  1477 "mirabelle" utility.
  1478 
  1479 * New proof method "sos" (sum of squares) for nonlinear real
  1480 arithmetic (originally due to John Harison). It requires theory
  1481 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1482 works well in practice on quantifier-free real arithmetic with +, -,
  1483 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1484 inequalities between polynomials.  It makes use of external
  1485 semidefinite programming solvers.  Method "sos" generates a
  1486 certificate that can be pasted into the proof thus avoiding the need
  1487 to call an external tool every time the proof is checked.  See
  1488 src/HOL/Library/Sum_Of_Squares.
  1489 
  1490 * New method "linarith" invokes existing linear arithmetic decision
  1491 procedure only.
  1492 
  1493 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1494 
  1495 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1496 Causes full type information to be output to the ATPs.  This slows
  1497 ATPs down considerably but eliminates a source of unsound "proofs"
  1498 that fail later.
  1499 
  1500 * New method "metisFT": A version of metis that uses full type
  1501 information in order to avoid failures of proof reconstruction.
  1502 
  1503 * New evaluator "approximate" approximates an real valued term using
  1504 the same method as the approximation method.
  1505 
  1506 * Method "approximate" now supports arithmetic expressions as
  1507 boundaries of intervals and implements interval splitting and Taylor
  1508 series expansion.
  1509 
  1510 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1511 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1512 
  1513 * New theory SupInf of the supremum and infimum operators for sets of
  1514 reals.
  1515 
  1516 * New theory Probability, which contains a development of measure
  1517 theory, eventually leading to Lebesgue integration and probability.
  1518 
  1519 * Extended Multivariate Analysis to include derivation and Brouwer's
  1520 fixpoint theorem.
  1521 
  1522 * Reorganization of number theory, INCOMPATIBILITY:
  1523   - new number theory development for nat and int, in theories Divides
  1524     and GCD as well as in new session Number_Theory
  1525   - some constants and facts now suffixed with _nat and _int
  1526     accordingly
  1527   - former session NumberTheory now named Old_Number_Theory, including
  1528     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1529   - moved theory Pocklington from src/HOL/Library to
  1530     src/HOL/Old_Number_Theory
  1531 
  1532 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1533 lcm of finite and infinite sets. It is shown that they form a complete
  1534 lattice.
  1535 
  1536 * Class semiring_div requires superclass no_zero_divisors and proof of
  1537 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1538 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1539 generalized to class semiring_div, subsuming former theorems
  1540 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1541 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1542 INCOMPATIBILITY.
  1543 
  1544 * Refinements to lattice classes and sets:
  1545   - less default intro/elim rules in locale variant, more default
  1546     intro/elim rules in class variant: more uniformity
  1547   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1548     le_inf_iff
  1549   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1550     sup_aci)
  1551   - renamed ACI to inf_sup_aci
  1552   - new class "boolean_algebra"
  1553   - class "complete_lattice" moved to separate theory
  1554     "Complete_Lattice"; corresponding constants (and abbreviations)
  1555     renamed and with authentic syntax:
  1556     Set.Inf ~>    Complete_Lattice.Inf
  1557     Set.Sup ~>    Complete_Lattice.Sup
  1558     Set.INFI ~>   Complete_Lattice.INFI
  1559     Set.SUPR ~>   Complete_Lattice.SUPR
  1560     Set.Inter ~>  Complete_Lattice.Inter
  1561     Set.Union ~>  Complete_Lattice.Union
  1562     Set.INTER ~>  Complete_Lattice.INTER
  1563     Set.UNION ~>  Complete_Lattice.UNION
  1564   - authentic syntax for
  1565     Set.Pow
  1566     Set.image
  1567   - mere abbreviations:
  1568     Set.empty               (for bot)
  1569     Set.UNIV                (for top)
  1570     Set.inter               (for inf, formerly Set.Int)
  1571     Set.union               (for sup, formerly Set.Un)
  1572     Complete_Lattice.Inter  (for Inf)
  1573     Complete_Lattice.Union  (for Sup)
  1574     Complete_Lattice.INTER  (for INFI)
  1575     Complete_Lattice.UNION  (for SUPR)
  1576   - object-logic definitions as far as appropriate
  1577 
  1578 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1579 Un_subset_iff are explicitly deleted as default simp rules; then also
  1580 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1581 deleted to achieve the desired effect.
  1582 
  1583 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1584 rules by default any longer; the same applies to min_max.inf_absorb1
  1585 etc.  INCOMPATIBILITY.
  1586 
  1587 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1588 pred_set_conv by default.  INCOMPATIBILITY.
  1589 
  1590 * Power operations on relations and functions are now one dedicated
  1591 constant "compow" with infix syntax "^^".  Power operation on
  1592 multiplicative monoids retains syntax "^" and is now defined generic
  1593 in class power.  INCOMPATIBILITY.
  1594 
  1595 * Relation composition "R O S" now has a more standard argument order:
  1596 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1597 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1598 break, since the O_assoc rule was not rewritten like this.  Fix using
  1599 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1600 
  1601 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1602 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1603 INCOMPATIBILITY.
  1604 
  1605 * Most rules produced by inductive and datatype package have mandatory
  1606 prefixes.  INCOMPATIBILITY.
  1607 
  1608 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1609 the attribute of the same name.  Each of the theorems in the list
  1610 DERIV_intros assumes composition with an additional function and
  1611 matches a variable to the derivative, which has to be solved by the
  1612 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1613 of most elementary terms.  Former Maclauren.DERIV_tac and
  1614 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1615 INCOMPATIBILITY.
  1616 
  1617 * Code generator attributes follow the usual underscore convention:
  1618     code_unfold     replaces    code unfold
  1619     code_post       replaces    code post
  1620     etc.
  1621   INCOMPATIBILITY.
  1622 
  1623 * Renamed methods:
  1624     sizechange -> size_change
  1625     induct_scheme -> induction_schema
  1626   INCOMPATIBILITY.
  1627 
  1628 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1629 INCOMPATIBILITY, use "undefined" directly.
  1630 
  1631 * Renamed theorems:
  1632     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1633     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1634     Suc_plus1 -> Suc_eq_plus1
  1635     *anti_sym -> *antisym*
  1636     vector_less_eq_def -> vector_le_def
  1637   INCOMPATIBILITY.
  1638 
  1639 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1640 INCOMPATIBILITY.
  1641 
  1642 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1643 INCOMPATIBILITY.
  1644 
  1645 
  1646 *** HOLCF ***
  1647 
  1648 * Theory Representable defines a class "rep" of domains that are
  1649 representable (via an ep-pair) in the universal domain type "udom".
  1650 Instances are provided for all type constructors defined in HOLCF.
  1651 
  1652 * The 'new_domain' command is a purely definitional version of the
  1653 domain package, for representable domains.  Syntax is identical to the
  1654 old domain package.  The 'new_domain' package also supports indirect
  1655 recursion using previously-defined type constructors.  See
  1656 src/HOLCF/ex/New_Domain.thy for examples.
  1657 
  1658 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1659 on the left-hand side of an equation, and then performs
  1660 simplification.  Rewriting is done using rules declared with the
  1661 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1662 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1663 
  1664 * The pattern-match compiler in 'fixrec' can now handle constructors
  1665 with HOL function types.  Pattern-match combinators for the Pair
  1666 constructor are pre-configured.
  1667 
  1668 * The 'fixrec' package now produces better fixed-point induction rules
  1669 for mutually-recursive definitions:  Induction rules have conclusions
  1670 of the form "P foo bar" instead of "P <foo, bar>".
  1671 
  1672 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1673 been renamed to "below".  The name "below" now replaces "less" in many
  1674 theorem names.  (Legacy theorem names using "less" are still supported
  1675 as well.)
  1676 
  1677 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1678 patterns can be used to generate strictness rules, or to make
  1679 functions more strict (much like the bang-patterns supported by the
  1680 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1681 examples.
  1682 
  1683 
  1684 *** ML ***
  1685 
  1686 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1687 errors and run-time exceptions, including detailed source positions.
  1688 
  1689 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1690 identified entries, with some additional information such as source
  1691 position, logical grouping etc.
  1692 
  1693 * Theory and context data is now introduced by the simplified and
  1694 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1695 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1696 copy operation) is still available for some time.
  1697 
  1698 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1699 provides a high-level programming interface to synchronized state
  1700 variables with atomic update.  This works via pure function
  1701 application within a critical section -- its runtime should be as
  1702 short as possible; beware of deadlocks if critical code is nested,
  1703 either directly or indirectly via other synchronized variables!
  1704 
  1705 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1706 wraps raw ML references, explicitly indicating their non-thread-safe
  1707 behaviour.  The Isar toplevel keeps this structure open, to
  1708 accommodate Proof General as well as quick and dirty interactive
  1709 experiments with references.
  1710 
  1711 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1712 parallel tactical reasoning.
  1713 
  1714 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1715 are similar to SUBPROOF, but are slightly more flexible: only the
  1716 specified parts of the subgoal are imported into the context, and the
  1717 body tactic may introduce new subgoals and schematic variables.
  1718 
  1719 * Old tactical METAHYPS, which does not observe the proof context, has
  1720 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1721 or Subgoal.FOCUS etc.
  1722 
  1723 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  1724 functors have their own ML name space there is no point to mark them
  1725 separately.)  Minor INCOMPATIBILITY.
  1726 
  1727 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  1728 
  1729 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  1730 INCOMPATIBILITY.
  1731 
  1732 * Operations of structure Skip_Proof no longer require quick_and_dirty
  1733 mode, which avoids critical setmp.
  1734 
  1735 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  1736 combinators for "args".  INCOMPATIBILITY, need to use simplified
  1737 Attrib/Method.setup introduced in Isabelle2009.
  1738 
  1739 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  1740 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  1741 last resort.  INCOMPATIBILITY.
  1742 
  1743 * Display.pretty_thm now requires a proper context (cf. former
  1744 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  1745 or even Display.pretty_thm_without_context as last resort.
  1746 INCOMPATIBILITY.
  1747 
  1748 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  1749 Syntax.pretty_typ/term directly, preferably with proper context
  1750 instead of global theory.
  1751 
  1752 
  1753 *** System ***
  1754 
  1755 * Further fine tuning of parallel proof checking, scales up to 8 cores
  1756 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  1757 usedir option -q.
  1758 
  1759 * Support for additional "Isabelle components" via etc/components, see
  1760 also the system manual.
  1761 
  1762 * The isabelle makeall tool now operates on all components with
  1763 IsaMakefile, not just hardwired "logics".
  1764 
  1765 * Removed "compress" option from isabelle-process and isabelle usedir;
  1766 this is always enabled.
  1767 
  1768 * Discontinued support for Poly/ML 4.x versions.
  1769 
  1770 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  1771 on a given logic image.  This requires the lighttpd webserver and is
  1772 currently supported on Linux only.
  1773 
  1774 
  1775 
  1776 New in Isabelle2009 (April 2009)
  1777 --------------------------------
  1778 
  1779 *** General ***
  1780 
  1781 * Simplified main Isabelle executables, with less surprises on
  1782 case-insensitive file-systems (such as Mac OS).
  1783 
  1784   - The main Isabelle tool wrapper is now called "isabelle" instead of
  1785     "isatool."
  1786 
  1787   - The former "isabelle" alias for "isabelle-process" has been
  1788     removed (should rarely occur to regular users).
  1789 
  1790   - The former "isabelle-interface" and its alias "Isabelle" have been
  1791     removed (interfaces are now regular Isabelle tools).
  1792 
  1793 Within scripts and make files, the Isabelle environment variables
  1794 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  1795 respectively.  (The latter are still available as legacy feature.)
  1796 
  1797 The old isabelle-interface wrapper could react in confusing ways if
  1798 the interface was uninstalled or changed otherwise.  Individual
  1799 interface tool configuration is now more explicit, see also the
  1800 Isabelle system manual.  In particular, Proof General is now available
  1801 via "isabelle emacs".
  1802 
  1803 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  1804 purge installed copies of Isabelle executables and re-run "isabelle
  1805 install -p ...", or use symlinks.
  1806 
  1807 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  1808 old ~/isabelle, which was slightly non-standard and apt to cause
  1809 surprises on case-insensitive file-systems (such as Mac OS).
  1810 
  1811 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  1812 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  1813 care is required when using older releases of Isabelle.  Note that
  1814 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  1815 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  1816 
  1817 * Proofs of fully specified statements are run in parallel on
  1818 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  1819 a regular 4-core machine, if the initial heap space is made reasonably
  1820 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  1821 
  1822 * The main reference manuals ("isar-ref", "implementation", and
  1823 "system") have been updated and extended.  Formally checked references
  1824 as hyperlinks are now available uniformly.
  1825 
  1826 
  1827 *** Pure ***
  1828 
  1829 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  1830 respects.  The most important changes are listed below.  See the
  1831 Tutorial on Locales ("locales" manual) for details.
  1832 
  1833 - In locale expressions, instantiation replaces renaming.  Parameters
  1834 must be declared in a for clause.  To aid compatibility with previous
  1835 parameter inheritance, in locale declarations, parameters that are not
  1836 'touched' (instantiation position "_" or omitted) are implicitly added
  1837 with their syntax at the beginning of the for clause.
  1838 
  1839 - Syntax from abbreviations and definitions in locales is available in
  1840 locale expressions and context elements.  The latter is particularly
  1841 useful in locale declarations.
  1842 
  1843 - More flexible mechanisms to qualify names generated by locale
  1844 expressions.  Qualifiers (prefixes) may be specified in locale
  1845 expressions, and can be marked as mandatory (syntax: "name!:") or
  1846 optional (syntax "name?:").  The default depends for plain "name:"
  1847 depends on the situation where a locale expression is used: in
  1848 commands 'locale' and 'sublocale' prefixes are optional, in
  1849 'interpretation' and 'interpret' prefixes are mandatory.  The old
  1850 implicit qualifiers derived from the parameter names of a locale are
  1851 no longer generated.
  1852 
  1853 - Command "sublocale l < e" replaces "interpretation l < e".  The
  1854 instantiation clause in "interpretation" and "interpret" (square
  1855 brackets) is no longer available.  Use locale expressions.
  1856 
  1857 - When converting proof scripts, mandatory qualifiers in
  1858 'interpretation' and 'interpret' should be retained by default, even
  1859 if this is an INCOMPATIBILITY compared to former behavior.  In the
  1860 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  1861 in locale expressions range over a single locale instance only.
  1862 
  1863 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  1864 In existing theorem specifications replace the includes element by the
  1865 respective context elements of the included locale, omitting those
  1866 that are already present in the theorem specification.  Multiple
  1867 assume elements of a locale should be replaced by a single one
  1868 involving the locale predicate.  In the proof body, declarations (most
  1869 notably theorems) may be regained by interpreting the respective
  1870 locales in the proof context as required (command "interpret").
  1871 
  1872 If using "includes" in replacement of a target solely because the
  1873 parameter types in the theorem are not as general as in the target,
  1874 consider declaring a new locale with additional type constraints on
  1875 the parameters (context element "constrains").
  1876 
  1877 - Discontinued "locale (open)".  INCOMPATIBILITY.
  1878 
  1879 - Locale interpretation commands no longer attempt to simplify goal.
  1880 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  1881 methods intro_locales and unfold_locales to clarify.
  1882 
  1883 - Locale interpretation commands no longer accept interpretation
  1884 attributes.  INCOMPATIBILITY.
  1885 
  1886 * Class declaration: so-called "base sort" must not be given in import
  1887 list any longer, but is inferred from the specification.  Particularly
  1888 in HOL, write
  1889 
  1890     class foo = ...
  1891 
  1892 instead of
  1893 
  1894     class foo = type + ...
  1895 
  1896 * Class target: global versions of theorems stemming do not carry a
  1897 parameter prefix any longer.  INCOMPATIBILITY.
  1898 
  1899 * Class 'instance' command no longer accepts attached definitions.
  1900 INCOMPATIBILITY, use proper 'instantiation' target instead.
  1901 
  1902 * Recovered hiding of consts, which was accidentally broken in
  1903 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  1904 makes c inaccessible; consider using ``hide (open) const c'' instead.
  1905 
  1906 * Slightly more coherent Pure syntax, with updated documentation in
  1907 isar-ref manual.  Removed locales meta_term_syntax and
  1908 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  1909 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  1910 directly in regular applications.
  1911 
  1912 * There is a new syntactic category "float_const" for signed decimal
  1913 fractions (e.g. 123.45 or -123.45).
  1914 
  1915 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  1916 interface with 'setup' command instead.
  1917 
  1918 * Command 'local_setup' is similar to 'setup', but operates on a local
  1919 theory context.
  1920 
  1921 * The 'axiomatization' command now only works within a global theory
  1922 context.  INCOMPATIBILITY.
  1923 
  1924 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  1925 hypotheses.  Sorts required in the course of reasoning need to be
  1926 covered by the constraints in the initial statement, completed by the
  1927 type instance information of the background theory.  Non-trivial sort
  1928 hypotheses, which rarely occur in practice, may be specified via
  1929 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  1930 
  1931   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  1932 
  1933 The result contains an implicit sort hypotheses as before --
  1934 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  1935 normalization.
  1936 
  1937 * Generalized Isar history, with support for linear undo, direct state
  1938 addressing etc.
  1939 
  1940 * Changed defaults for unify configuration options:
  1941 
  1942   unify_trace_bound = 50 (formerly 25)
  1943   unify_search_bound = 60 (formerly 30)
  1944 
  1945 * Different bookkeeping for code equations (INCOMPATIBILITY):
  1946 
  1947   a) On theory merge, the last set of code equations for a particular
  1948      constant is taken (in accordance with the policy applied by other
  1949      parts of the code generator framework).
  1950 
  1951   b) Code equations stemming from explicit declarations (e.g. code
  1952      attribute) gain priority over default code equations stemming
  1953      from definition, primrec, fun etc.
  1954 
  1955 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  1956 
  1957 * Unified theorem tables for both code generators.  Thus [code
  1958 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  1959 
  1960 * Command 'find_consts' searches for constants based on type and name
  1961 patterns, e.g.
  1962 
  1963     find_consts "_ => bool"
  1964 
  1965 By default, matching is against subtypes, but it may be restricted to
  1966 the whole type.  Searching by name is possible.  Multiple queries are
  1967 conjunctive and queries may be negated by prefixing them with a
  1968 hyphen:
  1969 
  1970     find_consts strict: "_ => bool" name: "Int" -"int => int"
  1971 
  1972 * New 'find_theorems' criterion "solves" matches theorems that
  1973 directly solve the current goal (modulo higher-order unification).
  1974 
  1975 * Auto solve feature for main theorem statements: whenever a new goal
  1976 is stated, "find_theorems solves" is called; any theorems that could
  1977 solve the lemma directly are listed as part of the goal state.
  1978 Cf. associated options in Proof General Isabelle settings menu,
  1979 enabled by default, with reasonable timeout for pathological cases of
  1980 higher-order unification.
  1981 
  1982 
  1983 *** Document preparation ***
  1984 
  1985 * Antiquotation @{lemma} now imitates a regular terminal proof,
  1986 demanding keyword 'by' and supporting the full method expression
  1987 syntax just like the Isar command 'by'.
  1988 
  1989 
  1990 *** HOL ***
  1991 
  1992 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  1993 points Main and Complex_Main remain as before.
  1994 
  1995 * Logic image HOL-Plain provides a minimal HOL with the most important
  1996 tools available (inductive, datatype, primrec, ...).  This facilitates
  1997 experimentation and tool development.  Note that user applications
  1998 (and library theories) should never refer to anything below theory
  1999 Main, as before.
  2000 
  2001 * Logic image HOL-Main stops at theory Main, and thus facilitates
  2002 experimentation due to shorter build times.
  2003 
  2004 * Logic image HOL-NSA contains theories of nonstandard analysis which
  2005 were previously part of former HOL-Complex.  Entry point Hyperreal
  2006 remains valid, but theories formerly using Complex_Main should now use
  2007 new entry point Hypercomplex.
  2008 
  2009 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  2010 Posix processes.  Avoids potentially expensive forking of the ML
  2011 process.  New thread-based implementation also works on non-Unix
  2012 platforms (Cygwin).  Provers are no longer hardwired, but defined
  2013 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  2014 commands are covered in the isar-ref manual.
  2015 
  2016 * Wrapper scripts for remote SystemOnTPTP service allows to use
  2017 sledgehammer without local ATP installation (Vampire etc.). Other
  2018 provers may be included via suitable ML wrappers, see also
  2019 src/HOL/ATP_Linkup.thy.
  2020 
  2021 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  2022 menu.
  2023 
  2024 * The metis method no longer fails because the theorem is too trivial
  2025 (contains the empty clause).
  2026 
  2027 * The metis method now fails in the usual manner, rather than raising
  2028 an exception, if it determines that it cannot prove the theorem.
  2029 
  2030 * Method "coherent" implements a prover for coherent logic (see also
  2031 src/Tools/coherent.ML).
  2032 
  2033 * Constants "undefined" and "default" replace "arbitrary".  Usually
  2034 "undefined" is the right choice to replace "arbitrary", though
  2035 logically there is no difference.  INCOMPATIBILITY.
  2036 
  2037 * Command "value" now integrates different evaluation mechanisms.  The
  2038 result of the first successful evaluation mechanism is printed.  In
  2039 square brackets a particular named evaluation mechanisms may be
  2040 specified (currently, [SML], [code] or [nbe]).  See further
  2041 src/HOL/ex/Eval_Examples.thy.
  2042 
  2043 * Normalization by evaluation now allows non-leftlinear equations.
  2044 Declare with attribute [code nbe].
  2045 
  2046 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  2047 as the structured Isar versions "cases" and "induct", cf. the
  2048 corresponding "cases" and "induct" attributes.  Mutual induction rules
  2049 are now presented as a list of individual projections
  2050 (e.g. foo_bar.inducts for types foo and bar); the old format with
  2051 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  2052 rare situations a different rule is selected --- notably nested tuple
  2053 elimination instead of former prod.exhaust: use explicit (case_tac t
  2054 rule: prod.exhaust) here.
  2055 
  2056 * Attributes "cases", "induct", "coinduct" support "del" option.
  2057 
  2058 * Removed fact "case_split_thm", which duplicates "case_split".
  2059 
  2060 * The option datatype has been moved to a new theory Option.  Renamed
  2061 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  2062 
  2063 * New predicate "strict_mono" classifies strict functions on partial
  2064 orders.  With strict functions on linear orders, reasoning about
  2065 (in)equalities is facilitated by theorems "strict_mono_eq",
  2066 "strict_mono_less_eq" and "strict_mono_less".
  2067 
  2068 * Some set operations are now proper qualified constants with
  2069 authentic syntax.  INCOMPATIBILITY:
  2070 
  2071     op Int ~>   Set.Int
  2072     op Un ~>    Set.Un
  2073     INTER ~>    Set.INTER
  2074     UNION ~>    Set.UNION
  2075     Inter ~>    Set.Inter
  2076     Union ~>    Set.Union
  2077     {} ~>       Set.empty
  2078     UNIV ~>     Set.UNIV
  2079 
  2080 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  2081 theory Set.
  2082 
  2083 * Auxiliary class "itself" has disappeared -- classes without any
  2084 parameter are treated as expected by the 'class' command.
  2085 
  2086 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  2087 
  2088 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  2089 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  2090 
  2091 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  2092 method "approximation".  It proves formulas on real values by using
  2093 interval arithmetic.  In the formulas are also the transcendental
  2094 functions sin, cos, tan, atan, ln, exp and the constant pi are
  2095 allowed. For examples see
  2096 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  2097 
  2098 * Theory "Reflection" now resides in HOL/Library.
  2099 
  2100 * Entry point to Word library now simply named "Word".
  2101 INCOMPATIBILITY.
  2102 
  2103 * Made source layout more coherent with logical distribution
  2104 structure:
  2105 
  2106     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  2107     src/HOL/Library/Code_Message.thy ~> src/HOL/
  2108     src/HOL/Library/GCD.thy ~> src/HOL/
  2109     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  2110     src/HOL/Library/Parity.thy ~> src/HOL/
  2111     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  2112     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  2113     src/HOL/Real/Lubs.thy ~> src/HOL/
  2114     src/HOL/Real/PReal.thy ~> src/HOL/
  2115     src/HOL/Real/Rational.thy ~> src/HOL/
  2116     src/HOL/Real/RComplete.thy ~> src/HOL/
  2117     src/HOL/Real/RealDef.thy ~> src/HOL/
  2118     src/HOL/Real/RealPow.thy ~> src/HOL/
  2119     src/HOL/Real/Real.thy ~> src/HOL/
  2120     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  2121     src/HOL/Complex/Complex.thy ~> src/HOL/
  2122     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  2123     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  2124     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  2125     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  2126     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  2127     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  2128     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  2129     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  2130     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  2131     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  2132     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  2133     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  2134     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  2135     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  2136     src/HOL/Real/Float ~> src/HOL/Library/
  2137     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  2138     src/HOL/Real/RealVector.thy ~> src/HOL/
  2139 
  2140     src/HOL/arith_data.ML ~> src/HOL/Tools
  2141     src/HOL/hologic.ML ~> src/HOL/Tools
  2142     src/HOL/simpdata.ML ~> src/HOL/Tools
  2143     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  2144     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  2145     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  2146     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  2147     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  2148     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  2149     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  2150 
  2151     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  2152     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  2153     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  2154     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  2155     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  2156     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  2157 
  2158 * If methods "eval" and "evaluation" encounter a structured proof
  2159 state with !!/==>, only the conclusion is evaluated to True (if
  2160 possible), avoiding strange error messages.
  2161 
  2162 * Method "sizechange" automates termination proofs using (a
  2163 modification of) the size-change principle.  Requires SAT solver.  See
  2164 src/HOL/ex/Termination.thy for examples.
  2165 
  2166 * Simplifier: simproc for let expressions now unfolds if bound
  2167 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  2168 
  2169 * Method "arith": Linear arithmetic now ignores all inequalities when
  2170 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  2171 
  2172 * New attribute "arith" for facts that should always be used
  2173 automatically by arithmetic. It is intended to be used locally in
  2174 proofs, e.g.
  2175 
  2176   assumes [arith]: "x > 0"
  2177 
  2178 Global usage is discouraged because of possible performance impact.
  2179 
  2180 * New classes "top" and "bot" with corresponding operations "top" and
  2181 "bot" in theory Orderings; instantiation of class "complete_lattice"
  2182 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  2183 
  2184 * Changed definition lemma "less_fun_def" in order to provide an
  2185 instance for preorders on functions; use lemma "less_le" instead.
  2186 INCOMPATIBILITY.
  2187 
  2188 * Theory Orderings: class "wellorder" moved here, with explicit
  2189 induction rule "less_induct" as assumption.  For instantiation of
  2190 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  2191 INCOMPATIBILITY.
  2192 
  2193 * Theory Orderings: added class "preorder" as superclass of "order".
  2194 INCOMPATIBILITY: Instantiation proofs for order, linorder
  2195 etc. slightly changed.  Some theorems named order_class.* now named
  2196 preorder_class.*.
  2197 
  2198 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  2199 "diag" to "Id_on".
  2200 
  2201 * Theory Finite_Set: added a new fold combinator of type
  2202 
  2203   ('a => 'b => 'b) => 'b => 'a set => 'b
  2204 
  2205 Occasionally this is more convenient than the old fold combinator
  2206 which is now defined in terms of the new one and renamed to
  2207 fold_image.
  2208 
  2209 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  2210 and "ring_simps" have been replaced by "algebra_simps" (which can be
  2211 extended with further lemmas!).  At the moment both still exist but
  2212 the former will disappear at some point.
  2213 
  2214 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  2215 class recpower.  Type-specific simp rules for various recpower types
  2216 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  2217 
  2218 rat_power_0    -> power_0
  2219 rat_power_Suc  -> power_Suc
  2220 realpow_0      -> power_0
  2221 realpow_Suc    -> power_Suc
  2222 complexpow_0   -> power_0
  2223 complexpow_Suc -> power_Suc
  2224 power_poly_0   -> power_0
  2225 power_poly_Suc -> power_Suc
  2226 
  2227 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  2228 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  2229 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  2230 of lemmas from Divides has been generalized from nat to class
  2231 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  2232 renames resulting from duplicate elimination:
  2233 
  2234     dvd_def_mod ~>          dvd_eq_mod_eq_0
  2235     zero_dvd_iff ~>         dvd_0_left_iff
  2236     dvd_0 ~>                dvd_0_right
  2237     DIVISION_BY_ZERO_DIV ~> div_by_0
  2238     DIVISION_BY_ZERO_MOD ~> mod_by_0
  2239     mult_div ~>             div_mult_self2_is_id
  2240     mult_mod ~>             mod_mult_self2_is_0
  2241 
  2242 * Theory IntDiv: removed many lemmas that are instances of class-based
  2243 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  2244 rename old lemmas as follows:
  2245 
  2246 dvd_diff               -> nat_dvd_diff
  2247 dvd_zminus_iff         -> dvd_minus_iff
  2248 mod_add1_eq            -> mod_add_eq
  2249 mod_mult1_eq           -> mod_mult_right_eq
  2250 mod_mult1_eq'          -> mod_mult_left_eq
  2251 mod_mult_distrib_mod   -> mod_mult_eq
  2252 nat_mod_add_left_eq    -> mod_add_left_eq
  2253 nat_mod_add_right_eq   -> mod_add_right_eq
  2254 nat_mod_div_trivial    -> mod_div_trivial
  2255 nat_mod_mod_trivial    -> mod_mod_trivial
  2256 zdiv_zadd_self1        -> div_add_self1
  2257 zdiv_zadd_self2        -> div_add_self2
  2258 zdiv_zmult_self1       -> div_mult_self2_is_id
  2259 zdiv_zmult_self2       -> div_mult_self1_is_id
  2260 zdvd_triv_left         -> dvd_triv_left
  2261 zdvd_triv_right        -> dvd_triv_right
  2262 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  2263 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  2264 zmod_zadd_left_eq      -> mod_add_left_eq
  2265 zmod_zadd_right_eq     -> mod_add_right_eq
  2266 zmod_zadd_self1        -> mod_add_self1
  2267 zmod_zadd_self2        -> mod_add_self2
  2268 zmod_zadd1_eq          -> mod_add_eq
  2269 zmod_zdiff1_eq         -> mod_diff_eq
  2270 zmod_zdvd_zmod         -> mod_mod_cancel
  2271 zmod_zmod_cancel       -> mod_mod_cancel
  2272 zmod_zmult_self1       -> mod_mult_self2_is_0
  2273 zmod_zmult_self2       -> mod_mult_self1_is_0
  2274 zmod_1                 -> mod_by_1
  2275 zdiv_1                 -> div_by_1
  2276 zdvd_abs1              -> abs_dvd_iff
  2277 zdvd_abs2              -> dvd_abs_iff
  2278 zdvd_refl              -> dvd_refl
  2279 zdvd_trans             -> dvd_trans
  2280 zdvd_zadd              -> dvd_add
  2281 zdvd_zdiff             -> dvd_diff
  2282 zdvd_zminus_iff        -> dvd_minus_iff
  2283 zdvd_zminus2_iff       -> minus_dvd_iff
  2284 zdvd_zmultD            -> dvd_mult_right
  2285 zdvd_zmultD2           -> dvd_mult_left
  2286 zdvd_zmult_mono        -> mult_dvd_mono
  2287 zdvd_0_right           -> dvd_0_right
  2288 zdvd_0_left            -> dvd_0_left_iff
  2289 zdvd_1_left            -> one_dvd
  2290 zminus_dvd_iff         -> minus_dvd_iff
  2291 
  2292 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  2293 
  2294 * The real numbers offer decimal input syntax: 12.34 is translated
  2295 into 1234/10^2. This translation is not reversed upon output.
  2296 
  2297 * Theory Library/Polynomial defines an abstract type 'a poly of
  2298 univariate polynomials with coefficients of type 'a.  In addition to
  2299 the standard ring operations, it also supports div and mod.  Code
  2300 generation is also supported, using list-style constructors.
  2301 
  2302 * Theory Library/Inner_Product defines a class of real_inner for real
  2303 inner product spaces, with an overloaded operation inner :: 'a => 'a
  2304 => real.  Class real_inner is a subclass of real_normed_vector from
  2305 theory RealVector.
  2306 
  2307 * Theory Library/Product_Vector provides instances for the product
  2308 type 'a * 'b of several classes from RealVector and Inner_Product.
  2309 Definitions of addition, subtraction, scalar multiplication, norms,
  2310 and inner products are included.
  2311 
  2312 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  2313 addition to the field operations, numerals and case syntax are also
  2314 supported.
  2315 
  2316 * Theory Library/Diagonalize provides constructive version of Cantor's
  2317 first diagonalization argument.
  2318 
  2319 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  2320 zlcm (for int); carried together from various gcd/lcm developements in
  2321 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  2322 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  2323 may recover tupled syntax as follows:
  2324 
  2325     hide (open) const gcd
  2326     abbreviation gcd where
  2327       "gcd == (%(a, b). GCD.gcd a b)"
  2328     notation (output)
  2329       GCD.gcd ("gcd '(_, _')")
  2330 
  2331 The same works for lcm, zgcd, zlcm.
  2332 
  2333 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  2334 instantiations for algebraic structures.  Removed some duplicate
  2335 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  2336 
  2337 * ML antiquotation @{code} takes a constant as argument and generates
  2338 corresponding code in background and inserts name of the corresponding
  2339 resulting ML value/function/datatype constructor binding in place.
  2340 All occurrences of @{code} with a single ML block are generated
  2341 simultaneously.  Provides a generic and safe interface for
  2342 instrumentalizing code generation.  See
  2343 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  2344 In future you ought to refrain from ad-hoc compiling generated SML
  2345 code on the ML toplevel.  Note that (for technical reasons) @{code}
  2346 cannot refer to constants for which user-defined serializations are
  2347 set.  Refer to the corresponding ML counterpart directly in that
  2348 cases.
  2349 
  2350 * Command 'rep_datatype': instead of theorem names the command now
  2351 takes a list of terms denoting the constructors of the type to be
  2352 represented as datatype.  The characteristic theorems have to be
  2353 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  2354 have disappeared in favour of existing ones:
  2355 
  2356     unit_induct                 ~> unit.induct
  2357     prod_induct                 ~> prod.induct
  2358     sum_induct                  ~> sum.induct
  2359     Suc_Suc_eq                  ~> nat.inject
  2360     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  2361 
  2362 
  2363 *** HOL-Algebra ***
  2364 
  2365 * New locales for orders and lattices where the equivalence relation
  2366 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  2367 locales use a record structure with field eq for the equivalence.
  2368 
  2369 * New theory of factorial domains.
  2370 
  2371 * Units_l_inv and Units_r_inv are now simp rules by default.
  2372 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  2373 and/or r_inv will now also require deletion of these lemmas.
  2374 
  2375 * Renamed the following theorems, INCOMPATIBILITY:
  2376 
  2377 UpperD ~> Upper_memD
  2378 LowerD ~> Lower_memD
  2379 least_carrier ~> least_closed
  2380 greatest_carrier ~> greatest_closed
  2381 greatest_Lower_above ~> greatest_Lower_below
  2382 one_zero ~> carrier_one_zero
  2383 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  2384 
  2385 
  2386 *** HOL-Nominal ***
  2387 
  2388 * Nominal datatypes can now contain type-variables.
  2389 
  2390 * Commands 'nominal_inductive' and 'equivariance' work with local
  2391 theory targets.
  2392 
  2393 * Nominal primrec can now works with local theory targets and its
  2394 specification syntax now conforms to the general format as seen in
  2395 'inductive' etc.
  2396 
  2397 * Method "perm_simp" honours the standard simplifier attributes
  2398 (no_asm), (no_asm_use) etc.
  2399 
  2400 * The new predicate #* is defined like freshness, except that on the
  2401 left hand side can be a set or list of atoms.
  2402 
  2403 * Experimental command 'nominal_inductive2' derives strong induction
  2404 principles for inductive definitions.  In contrast to
  2405 'nominal_inductive', which can only deal with a fixed number of
  2406 binders, it can deal with arbitrary expressions standing for sets of
  2407 atoms to be avoided.  The only inductive definition we have at the
  2408 moment that needs this generalisation is the typing rule for Lets in
  2409 the algorithm W:
  2410 
  2411  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  2412  -----------------------------------------------------------------
  2413          Gamma |- Let x be t1 in t2 : T2
  2414 
  2415 In this rule one wants to avoid all the binders that are introduced by
  2416 "close Gamma T1".  We are looking for other examples where this
  2417 feature might be useful.  Please let us know.
  2418 
  2419 
  2420 *** HOLCF ***
  2421 
  2422 * Reimplemented the simplification procedure for proving continuity
  2423 subgoals.  The new simproc is extensible; users can declare additional
  2424 continuity introduction rules with the attribute [cont2cont].
  2425 
  2426 * The continuity simproc now uses a different introduction rule for
  2427 solving continuity subgoals on terms with lambda abstractions.  In
  2428 some rare cases the new simproc may fail to solve subgoals that the
  2429 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  2430 Potential INCOMPATIBILITY.
  2431 
  2432 * Command 'fixrec': specification syntax now conforms to the general
  2433 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  2434 examples.  INCOMPATIBILITY.
  2435 
  2436 
  2437 *** ZF ***
  2438 
  2439 * Proof of Zorn's Lemma for partial orders.
  2440 
  2441 
  2442 *** ML ***
  2443 
  2444 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  2445 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  2446 depends on multithreading, so timouts will not work before Poly/ML
  2447 5.2.1!
  2448 
  2449 * High-level support for concurrent ML programming, see
  2450 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  2451 particularly convenient to organize independent functional
  2452 computations.  The concept of "synchronized variables" provides a
  2453 higher-order interface for components with shared state, avoiding the
  2454 delicate details of mutexes and condition variables.  (Requires
  2455 Poly/ML 5.2.1 or later.)
  2456 
  2457 * ML bindings produced via Isar commands are stored within the Isar
  2458 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2459 become thread-safe and work with undo as expected (concerning
  2460 top-level bindings, not side-effects on global references).
  2461 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2462 compiler at runtime; really global bindings need to be given outside a
  2463 theory.  (Requires Poly/ML 5.2 or later.)
  2464 
  2465 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2466 context.  Top-level ML bindings are stored within the proof context in
  2467 a purely sequential fashion, disregarding the nested proof structure.
  2468 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2469 proof.  (Requires Poly/ML 5.2 or later.)
  2470 
  2471 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2472 and Method.setup, as well as Isar commands 'attribute_setup' and
  2473 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2474 existing code accordingly, or use plain 'setup' together with old
  2475 Method.add_method.
  2476 
  2477 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2478 to 'a -> thm, while results are always tagged with an authentic oracle
  2479 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2480 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2481 accordingly.  Note that extra performance may be gained by producing
  2482 the cterm carefully, avoiding slow Thm.cterm_of.
  2483 
  2484 * Simplified interface for defining document antiquotations via
  2485 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2486 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2487 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2488 examples.
  2489 
  2490 * More systematic treatment of long names, abstract name bindings, and
  2491 name space operations.  Basic operations on qualified names have been
  2492 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2493 Long_Name.append.  Old type bstring has been mostly replaced by
  2494 abstract type binding (see structure Binding), which supports precise
  2495 qualification by packages and local theory targets, as well as proper
  2496 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2497 bstring values into Binding.name, or better pass through abstract
  2498 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2499 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2500 
  2501 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2502 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2503 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2504 
  2505 * Disposed old type and term read functions (Sign.read_def_typ,
  2506 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2507 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2508 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2509 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2510 resort for legacy applications.
  2511 
  2512 * Disposed old declarations, tactics, tactic combinators that refer to
  2513 the simpset or claset of an implicit theory (such as Addsimps,
  2514 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2515 embedded ML text, or local_simpset_of with a proper context passed as
  2516 explicit runtime argument.
  2517 
  2518 * Rules and tactics that read instantiations (read_instantiate,
  2519 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2520 context, which is required for parsing and type-checking.  Moreover,
  2521 the variables are specified as plain indexnames, not string encodings
  2522 thereof.  INCOMPATIBILITY.
  2523 
  2524 * Generic Toplevel.add_hook interface allows to analyze the result of
  2525 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2526 for theorem dependency output of transactions resulting in a new
  2527 theory state.
  2528 
  2529 * ML antiquotations: block-structured compilation context indicated by
  2530 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2531 
  2532   @{binding name}                         - basic name binding
  2533   @{let ?pat = term}                      - term abbreviation (HO matching)
  2534   @{note name = fact}                     - fact abbreviation
  2535   @{thm fact}                             - singleton fact (with attributes)
  2536   @{thms fact}                            - general fact (with attributes)
  2537   @{lemma prop by method}                 - singleton goal
  2538   @{lemma prop by meth1 meth2}            - singleton goal
  2539   @{lemma prop1 ... propN by method}      - general goal
  2540   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2541   @{lemma (open) ...}                     - open derivation
  2542 
  2543 
  2544 *** System ***
  2545 
  2546 * The Isabelle "emacs" tool provides a specific interface to invoke
  2547 Proof General / Emacs, with more explicit failure if that is not
  2548 installed (the old isabelle-interface script silently falls back on
  2549 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2550 installation location of the Proof General distribution.
  2551 
  2552 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2553 the Isabelle process into a JVM/Scala application.  See
  2554 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2555 process wrapper has been discontinued.)
  2556 
  2557 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2558 
  2559 * Various status messages (with exact source position information) are
  2560 emitted, if proper markup print mode is enabled.  This allows
  2561 user-interface components to provide detailed feedback on internal
  2562 prover operations.
  2563 
  2564 
  2565 
  2566 New in Isabelle2008 (June 2008)
  2567 -------------------------------
  2568 
  2569 *** General ***
  2570 
  2571 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2572 and updated, with formally checked references as hyperlinks.
  2573 
  2574 * Theory loader: use_thy (and similar operations) no longer set the
  2575 implicit ML context, which was occasionally hard to predict and in
  2576 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2577 provides a proper context already.
  2578 
  2579 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2580 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2581 'use' within a theory file will do the job.
  2582 
  2583 * Name space merge now observes canonical order, i.e. the second space
  2584 is inserted into the first one, while existing entries in the first
  2585 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2586 swap theory imports.
  2587 
  2588 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2589 INCOMPATIBILITY in identifier syntax etc.
  2590 
  2591 * Outer syntax: string tokens no longer admit escaped white space,
  2592 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2593 white space without escapes.
  2594 
  2595 * Outer syntax: string tokens may contain arbitrary character codes
  2596 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2597 "foo_bar".
  2598 
  2599 
  2600 *** Pure ***
  2601 
  2602 * Context-dependent token translations.  Default setup reverts locally
  2603 fixed variables, and adds hilite markup for undeclared frees.
  2604 
  2605 * Unused theorems can be found using the new command 'unused_thms'.
  2606 There are three ways of invoking it:
  2607 
  2608 (1) unused_thms
  2609      Only finds unused theorems in the current theory.
  2610 
  2611 (2) unused_thms thy_1 ... thy_n -
  2612      Finds unused theorems in the current theory and all of its ancestors,
  2613      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2614 
  2615 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2616      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2617      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2618      their ancestors.
  2619 
  2620 In order to increase the readability of the list produced by
  2621 unused_thms, theorems that have been created by a particular instance
  2622 of a theory command such as 'inductive' or 'function' are considered
  2623 to belong to the same "group", meaning that if at least one theorem in
  2624 this group is used, the other theorems in the same group are no longer
  2625 reported as unused.  Moreover, if all theorems in the group are
  2626 unused, only one theorem in the group is displayed.
  2627 
  2628 Note that proof objects have to be switched on in order for
  2629 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2630 usually the case when using Proof General with the default settings).
  2631 
  2632 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2633 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2634 duplicate fact bindings, or even accidental fact duplications.  Note
  2635 that tools may maintain dynamically scoped facts systematically, using
  2636 PureThy.add_thms_dynamic.
  2637 
  2638 * Command 'hide' now allows to hide from "fact" name space as well.
  2639 
  2640 * Eliminated destructive theorem database, simpset, claset, and
  2641 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2642 update of theories within ML code.
  2643 
  2644 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2645 INCOMPATIBILITY, object-logics depending on former Pure require
  2646 additional setup PureThy.old_appl_syntax_setup; object-logics
  2647 depending on former CPure need to refer to Pure.
  2648 
  2649 * Commands 'use' and 'ML' are now purely functional, operating on
  2650 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2651 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2652 INCOMPATIBILITY.
  2653 
  2654 * Command 'setup': discontinued implicit version with ML reference.
  2655 
  2656 * Instantiation target allows for simultaneous specification of class
  2657 instance operations together with an instantiation proof.
  2658 Type-checking phase allows to refer to class operations uniformly.
  2659 See src/HOL/Complex/Complex.thy for an Isar example and
  2660 src/HOL/Library/Eval.thy for an ML example.
  2661 
  2662 * Indexing of literal facts: be more serious about including only
  2663 facts from the visible specification/proof context, but not the
  2664 background context (locale etc.).  Affects `prop` notation and method
  2665 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2666 situations.
  2667 
  2668 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2669 "(open)" option, which used to expose internal bound variables to the
  2670 proof text.
  2671 
  2672 * Isar statements: removed obsolete case "rule_context".
  2673 INCOMPATIBILITY, better use explicit fixes/assumes.
  2674 
  2675 * Locale proofs: default proof step now includes 'unfold_locales';
  2676 hence 'proof' without argument may be used to unfold locale
  2677 predicates.
  2678 
  2679 
  2680 *** Document preparation ***
  2681 
  2682 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2683 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2684 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2685 spot); renamed link color from "darkblue" to "linkcolor" (default
  2686 value unchanged, can be redefined via \definecolor); no longer sets
  2687 "a4paper" option (unnecessary or even intrusive).
  2688 
  2689 * Antiquotation @{lemma A method} proves proposition A by the given
  2690 method (either a method name or a method name plus (optional) method
  2691 arguments in parentheses) and prints A just like @{prop A}.
  2692 
  2693 
  2694 *** HOL ***
  2695 
  2696 * New primrec package.  Specification syntax conforms in style to
  2697 definition/function/....  No separate induction rule is provided.  The
  2698 "primrec" command distinguishes old-style and new-style specifications
  2699 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2700 When adjusting theories, beware: constants stemming from new-style
  2701 primrec specifications have authentic syntax.
  2702 
  2703 * Metis prover is now an order of magnitude faster, and also works
  2704 with multithreading.
  2705 
  2706 * Metis: the maximum number of clauses that can be produced from a
  2707 theorem is now given by the attribute max_clauses.  Theorems that
  2708 exceed this number are ignored, with a warning printed.
  2709 
  2710 * Sledgehammer no longer produces structured proofs by default. To
  2711 enable, declare [[sledgehammer_full = true]].  Attributes
  2712 reconstruction_modulus, reconstruction_sorts renamed
  2713 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2714 
  2715 * Method "induct_scheme" derives user-specified induction rules
  2716 from well-founded induction and completeness of patterns. This factors
  2717 out some operations that are done internally by the function package
  2718 and makes them available separately.  See
  2719 src/HOL/ex/Induction_Scheme.thy for examples.
  2720 
  2721 * More flexible generation of measure functions for termination
  2722 proofs: Measure functions can be declared by proving a rule of the
  2723 form "is_measure f" and giving it the [measure_function] attribute.
  2724 The "is_measure" predicate is logically meaningless (always true), and
  2725 just guides the heuristic.  To find suitable measure functions, the
  2726 termination prover sets up the goal "is_measure ?f" of the appropriate
  2727 type and generates all solutions by prolog-style backwards proof using
  2728 the declared rules.
  2729 
  2730 This setup also deals with rules like 
  2731 
  2732   "is_measure f ==> is_measure (list_size f)"
  2733 
  2734 which accommodates nested datatypes that recurse through lists.
  2735 Similar rules are predeclared for products and option types.
  2736 
  2737 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  2738 
  2739   INCOMPATIBILITIES:
  2740 
  2741   - Definitions of overloaded constants on sets have to be replaced by
  2742     definitions on => and bool.
  2743 
  2744   - Some definitions of overloaded operators on sets can now be proved
  2745     using the definitions of the operators on => and bool.  Therefore,
  2746     the following theorems have been renamed:
  2747 
  2748       subset_def   -> subset_eq
  2749       psubset_def  -> psubset_eq
  2750       set_diff_def -> set_diff_eq
  2751       Compl_def    -> Compl_eq
  2752       Sup_set_def  -> Sup_set_eq
  2753       Inf_set_def  -> Inf_set_eq
  2754       sup_set_def  -> sup_set_eq
  2755       inf_set_def  -> inf_set_eq
  2756 
  2757   - Due to the incompleteness of the HO unification algorithm, some
  2758     rules such as subst may require manual instantiation, if some of
  2759     the unknowns in the rule is a set.
  2760 
  2761   - Higher order unification and forward proofs:
  2762     The proof pattern
  2763 
  2764       have "P (S::'a set)" <...>
  2765       then have "EX S. P S" ..
  2766 
  2767     no longer works (due to the incompleteness of the HO unification
  2768     algorithm) and must be replaced by the pattern
  2769 
  2770       have "EX S. P S"
  2771       proof
  2772         show "P S" <...>
  2773       qed
  2774 
  2775   - Calculational reasoning with subst (or similar rules):
  2776     The proof pattern
  2777 
  2778       have "P (S::'a set)" <...>
  2779       also have "S = T" <...>
  2780       finally have "P T" .
  2781 
  2782     no longer works (for similar reasons as the previous example) and
  2783     must be replaced by something like
  2784 
  2785       have "P (S::'a set)" <...>
  2786       moreover have "S = T" <...>
  2787       ultimately have "P T" by simp
  2788 
  2789   - Tactics or packages written in ML code:
  2790     Code performing pattern matching on types via
  2791 
  2792       Type ("set", [T]) => ...
  2793 
  2794     must be rewritten. Moreover, functions like strip_type or
  2795     binder_types no longer return the right value when applied to a
  2796     type of the form
  2797 
  2798       T1 => ... => Tn => U => bool
  2799 
  2800     rather than
  2801 
  2802       T1 => ... => Tn => U set
  2803 
  2804 * Merged theories Wellfounded_Recursion, Accessible_Part and
  2805 Wellfounded_Relations to theory Wellfounded.
  2806 
  2807 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  2808 
  2809 * Class finite no longer treats UNIV as class parameter.  Use class
  2810 enum from theory Library/Enum instead to achieve a similar effect.
  2811 INCOMPATIBILITY.
  2812 
  2813 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  2814 and "Cons".  INCOMPATIBILITY.
  2815 
  2816 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  2817 Potential INCOMPATIBILITY.
  2818 
  2819 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  2820 injective_fst_snd removed, use split_eta and prod_eqI instead.
  2821 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  2822 
  2823 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  2824 the same name in theory Orderings:
  2825 
  2826   less_trans
  2827   less_linear
  2828   le_imp_less_or_eq
  2829   le_less_trans
  2830   less_le_trans
  2831   less_not_sym
  2832   less_asym
  2833 
  2834 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  2835 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  2836 and different variable names.
  2837 
  2838 * Library/Option_ord.thy: Canonical order on option type.
  2839 
  2840 * Library/RBT.thy: Red-black trees, an efficient implementation of
  2841 finite maps.
  2842 
  2843 * Library/Countable.thy: Type class for countable types.
  2844 
  2845 * Theory Int: The representation of numerals has changed.  The infix
  2846 operator BIT and the bit datatype with constructors B0 and B1 have
  2847 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  2848 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  2849 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  2850 accordingly.
  2851 
  2852 * Theory Nat: definition of <= and < on natural numbers no longer
  2853 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  2854 le_def and less_def have disappeared.  Consider lemmas not_less
  2855 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  2856 
  2857 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  2858 (whose purpose mainly is for various fold_set functionals) have been
  2859 abandoned in favor of the existing algebraic classes
  2860 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  2861 lower_semilattice (resp. upper_semilattice) and linorder.
  2862 INCOMPATIBILITY.
  2863 
  2864 * Theory Transitive_Closure: induct and cases rules now declare proper
  2865 case_names ("base" and "step").  INCOMPATIBILITY.
  2866 
  2867 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  2868 lattices.  The form set-specific version is available as
  2869 Inductive.lfp_ordinal_induct_set.
  2870 
  2871 * Renamed theorems "power.simps" to "power_int.simps".
  2872 INCOMPATIBILITY.
  2873 
  2874 * Class semiring_div provides basic abstract properties of semirings
  2875 with division and modulo operations.  Subsumes former class dvd_mod.
  2876 
  2877 * Merged theories IntDef, Numeral and IntArith into unified theory
  2878 Int.  INCOMPATIBILITY.
  2879 
  2880 * Theory Library/Code_Index: type "index" now represents natural
  2881 numbers rather than integers.  INCOMPATIBILITY.
  2882 
  2883 * New class "uminus" with operation "uminus" (split of from class
  2884 "minus" which now only has operation "minus", binary).
  2885 INCOMPATIBILITY.
  2886 
  2887 * Constants "card", "internal_split", "option_map" now with authentic
  2888 syntax.  INCOMPATIBILITY.
  2889 
  2890 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  2891 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  2892 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  2893 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  2894 Sup_set_def, le_def, less_def, option_map_def now with object
  2895 equality.  INCOMPATIBILITY.
  2896 
  2897 * Records. Removed K_record, and replaced it by pure lambda term
  2898 %x. c. The simplifier setup is now more robust against eta expansion.
  2899 INCOMPATIBILITY: in cases explicitly referring to K_record.
  2900 
  2901 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  2902 
  2903 * Library/ListVector: new theory of arithmetic vector operations.
  2904 
  2905 * Library/Order_Relation: new theory of various orderings as sets of
  2906 pairs.  Defines preorders, partial orders, linear orders and
  2907 well-orders on sets and on types.
  2908 
  2909 
  2910 *** ZF ***
  2911 
  2912 * Renamed some theories to allow to loading both ZF and HOL in the
  2913 same session:
  2914 
  2915   Datatype  -> Datatype_ZF
  2916   Inductive -> Inductive_ZF
  2917   Int       -> Int_ZF
  2918   IntDiv    -> IntDiv_ZF
  2919   Nat       -> Nat_ZF
  2920   List      -> List_ZF
  2921   Main      -> Main_ZF
  2922 
  2923 INCOMPATIBILITY: ZF theories that import individual theories below
  2924 Main might need to be adapted.  Regular theory Main is still
  2925 available, as trivial extension of Main_ZF.
  2926 
  2927 
  2928 *** ML ***
  2929 
  2930 * ML within Isar: antiquotation @{const name} or @{const
  2931 name(typargs)} produces statically-checked Const term.
  2932 
  2933 * Functor NamedThmsFun: data is available to the user as dynamic fact
  2934 (of the same name).  Removed obsolete print command.
  2935 
  2936 * Removed obsolete "use_legacy_bindings" function.
  2937 
  2938 * The ``print mode'' is now a thread-local value derived from a global
  2939 template (the former print_mode reference), thus access becomes
  2940 non-critical.  The global print_mode reference is for session
  2941 management only; user-code should use print_mode_value,
  2942 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  2943 
  2944 * Functions system/system_out provide a robust way to invoke external
  2945 shell commands, with propagation of interrupts (requires Poly/ML
  2946 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  2947 
  2948 
  2949 *** System ***
  2950 
  2951 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  2952 in accordance with Proof General 3.7, which prefers GNU emacs.
  2953 
  2954 * isatool tty runs Isabelle process with plain tty interaction;
  2955 optional line editor may be specified via ISABELLE_LINE_EDITOR
  2956 setting, the default settings attempt to locate "ledit" and "rlwrap".
  2957 
  2958 * isatool browser now works with Cygwin as well, using general
  2959 "javapath" function defined in Isabelle process environment.
  2960 
  2961 * YXML notation provides a simple and efficient alternative to
  2962 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  2963 isatool yxml as described in the Isabelle system manual.
  2964 
  2965 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  2966 provides general wrapper for managing an Isabelle process in a robust
  2967 fashion, with ``cooked'' output from stdin/stderr.
  2968 
  2969 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  2970 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  2971 
  2972 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  2973 way of changing the user's settings is via
  2974 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  2975 script.
  2976 
  2977 * Multithreading.max_threads := 0 refers to the number of actual CPU
  2978 cores of the underlying machine, which is a good starting point for
  2979 optimal performance tuning.  The corresponding usedir option -M allows
  2980 "max" as an alias for "0".  WARNING: does not work on certain versions
  2981 of Mac OS (with Poly/ML 5.1).
  2982 
  2983 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  2984 adverse effect of Isabelle flooding interactive front-ends (notably
  2985 ProofGeneral / XEmacs).
  2986 
  2987 
  2988 
  2989 New in Isabelle2007 (November 2007)
  2990 -----------------------------------
  2991 
  2992 *** General ***
  2993 
  2994 * More uniform information about legacy features, notably a
  2995 warning/error of "Legacy feature: ...", depending on the state of the
  2996 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  2997 legacy features will disappear eventually.
  2998 
  2999 * Theory syntax: the header format ``theory A = B + C:'' has been
  3000 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  3001 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  3002 
  3003 * Theory syntax: the old non-Isar theory file format has been
  3004 discontinued altogether.  Note that ML proof scripts may still be used
  3005 with Isar theories; migration is usually quite simple with the ML
  3006 function use_legacy_bindings.  INCOMPATIBILITY.
  3007 
  3008 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  3009 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  3010 quotes.
  3011 
  3012 * Theory loader: be more serious about observing the static theory
  3013 header specifications (including optional directories), but not the
  3014 accidental file locations of previously successful loads.  The strict
  3015 update policy of former update_thy is now already performed by
  3016 use_thy, so the former has been removed; use_thys updates several
  3017 theories simultaneously, just as 'imports' within a theory header
  3018 specification, but without merging the results.  Potential
  3019 INCOMPATIBILITY: may need to refine theory headers and commands
  3020 ROOT.ML which depend on load order.
  3021 
  3022 * Theory loader: optional support for content-based file
  3023 identification, instead of the traditional scheme of full physical
  3024 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  3025 (cf. the system manual).  The new scheme allows to work with
  3026 non-finished theories in persistent session images, such that source
  3027 files may be moved later on without requiring reloads.
  3028 
  3029 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3030 file (with the same base name as the theory) are considered a legacy
  3031 feature, which will disappear eventually. Even now, the theory loader
  3032 no longer maintains dependencies on such files.
  3033 
  3034 * Syntax: the scope for resolving ambiguities via type-inference is
  3035 now limited to individual terms, instead of whole simultaneous
  3036 specifications as before. This greatly reduces the complexity of the
  3037 syntax module and improves flexibility by separating parsing and
  3038 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  3039 'fixes' etc.) are required in rare situations.
  3040 
  3041 * Syntax: constants introduced by new-style packages ('definition',
  3042 'abbreviation' etc.) are passed through the syntax module in
  3043 ``authentic mode''. This means that associated mixfix annotations
  3044 really stick to such constants, independently of potential name space
  3045 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  3046 trees are represented slightly differently, may need to adapt syntax
  3047 translations accordingly. Use CONST marker in 'translations' and
  3048 @{const_syntax} antiquotation in 'parse_translation' etc.
  3049 
  3050 * Legacy goal package: reduced interface to the bare minimum required
  3051 to keep existing proof scripts running.  Most other user-level
  3052 functions are now part of the OldGoals structure, which is *not* open
  3053 by default (consider isatool expandshort before open OldGoals).
  3054 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  3055 these tend to cause confusion about the actual goal (!) context being
  3056 used here, which is not necessarily the same as the_context().
  3057 
  3058 * Command 'find_theorems': supports "*" wild-card in "name:"
  3059 criterion; "with_dups" option.  Certain ProofGeneral versions might
  3060 support a specific search form (see ProofGeneral/CHANGES).
  3061 
  3062 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  3063 by default, which means that "prems" (and also "fixed variables") are
  3064 suppressed from proof state output.  Note that the ProofGeneral
  3065 settings mechanism allows to change and save options persistently, but
  3066 older versions of Isabelle will fail to start up if a negative prems
  3067 limit is imposed.
  3068 
  3069 * Local theory targets may be specified by non-nested blocks of
  3070 ``context/locale/class ... begin'' followed by ``end''.  The body may
  3071 contain definitions, theorems etc., including any derived mechanism
  3072 that has been implemented on top of these primitives.  This concept
  3073 generalizes the existing ``theorem (in ...)'' towards more versatility
  3074 and scalability.
  3075 
  3076 * Proof General interface: proper undo of final 'end' command;
  3077 discontinued Isabelle/classic mode (ML proof scripts).
  3078 
  3079 
  3080 *** Document preparation ***
  3081 
  3082 * Added antiquotation @{theory name} which prints the given name,
  3083 after checking that it refers to a valid ancestor theory in the
  3084 current context.
  3085 
  3086 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  3087 check the given source text as ML type/structure, printing verbatim.
  3088 
  3089 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  3090 "c args == rhs" given in the current context.  (Any number of
  3091 arguments may be given on the LHS.)
  3092 
  3093 
  3094 *** Pure ***
  3095 
  3096 * The 'class' package offers a combination of axclass and locale to
  3097 achieve Haskell-like type classes in Isabelle.  Definitions and
  3098 theorems within a class context produce both relative results (with
  3099 implicit parameters according to the locale context), and polymorphic
  3100 constants with qualified polymorphism (according to the class
  3101 context).  Within the body context of a 'class' target, a separate
  3102 syntax layer ("user space type system") takes care of converting
  3103 between global polymorphic consts and internal locale representation.
  3104 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  3105 "isatool doc classes" provides a tutorial.
  3106 
  3107 * Generic code generator framework allows to generate executable
  3108 code for ML and Haskell (including Isabelle classes).  A short usage
  3109 sketch:
  3110 
  3111     internal compilation:
  3112         export_code <list of constants (term syntax)> in SML
  3113     writing SML code to a file:
  3114         export_code <list of constants (term syntax)> in SML <filename>
  3115     writing OCaml code to a file:
  3116         export_code <list of constants (term syntax)> in OCaml <filename>
  3117     writing Haskell code to a bunch of files:
  3118         export_code <list of constants (term syntax)> in Haskell <filename>
  3119 
  3120     evaluating closed propositions to True/False using code generation:
  3121         method ``eval''
  3122 
  3123 Reasonable default setup of framework in HOL.
  3124 
  3125 Theorem attributs for selecting and transforming function equations theorems:
  3126 
  3127     [code fun]:        select a theorem as function equation for a specific constant
  3128     [code fun del]:    deselect a theorem as function equation for a specific constant
  3129     [code inline]:     select an equation theorem for unfolding (inlining) in place
  3130     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  3131 
  3132 User-defined serializations (target in {SML, OCaml, Haskell}):
  3133 
  3134     code_const <and-list of constants (term syntax)>
  3135       {(target) <and-list of const target syntax>}+
  3136 
  3137     code_type <and-list of type constructors>
  3138       {(target) <and-list of type target syntax>}+
  3139 
  3140     code_instance <and-list of instances>
  3141       {(target)}+
  3142         where instance ::= <type constructor> :: <class>
  3143 
  3144     code_class <and_list of classes>
  3145       {(target) <and-list of class target syntax>}+
  3146         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  3147 
  3148 code_instance and code_class only are effective to target Haskell.
  3149 
  3150 For example usage see src/HOL/ex/Codegenerator.thy and
  3151 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  3152 generation from Isabelle/HOL theories is available via "isatool doc
  3153 codegen".
  3154 
  3155 * Code generator: consts in 'consts_code' Isar commands are now
  3156 referred to by usual term syntax (including optional type
  3157 annotations).
  3158 
  3159 * Command 'no_translations' removes translation rules from theory
  3160 syntax.
  3161 
  3162 * Overloaded definitions are now actually checked for acyclic
  3163 dependencies.  The overloading scheme is slightly more general than
  3164 that of Haskell98, although Isabelle does not demand an exact
  3165 correspondence to type class and instance declarations.
  3166 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  3167 exotic versions of overloading -- at the discretion of the user!
  3168 
  3169 Polymorphic constants are represented via type arguments, i.e. the
  3170 instantiation that matches an instance against the most general
  3171 declaration given in the signature.  For example, with the declaration
  3172 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  3173 as c(nat).  Overloading is essentially simultaneous structural
  3174 recursion over such type arguments.  Incomplete specification patterns
  3175 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  3176 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  3177 Command 'print_theory' outputs the normalized system of recursive
  3178 equations, see section "definitions".
  3179 
  3180 * Configuration options are maintained within the theory or proof
  3181 context (with name and type bool/int/string), providing a very simple
  3182 interface to a poor-man's version of general context data.  Tools may
  3183 declare options in ML (e.g. using Attrib.config_int) and then refer to
  3184 these values using Config.get etc.  Users may change options via an
  3185 associated attribute of the same name.  This form of context
  3186 declaration works particularly well with commands 'declare' or
  3187 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  3188 very easy to avoid global references, which would not observe Isar
  3189 toplevel undo/redo and fail to work with multithreading.
  3190 
  3191 Various global ML references of Pure and HOL have been turned into
  3192 configuration options:
  3193 
  3194   Unify.search_bound		unify_search_bound
  3195   Unify.trace_bound		unify_trace_bound
  3196   Unify.trace_simp		unify_trace_simp
  3197   Unify.trace_types		unify_trace_types
  3198   Simplifier.simp_depth_limit	simp_depth_limit
  3199   Blast.depth_limit		blast_depth_limit
  3200   DatatypeProp.dtK		datatype_distinctness_limit
  3201   fast_arith_neq_limit  	fast_arith_neq_limit
  3202   fast_arith_split_limit	fast_arith_split_limit
  3203 
  3204 * Named collections of theorems may be easily installed as context
  3205 data using the functor NamedThmsFun (see also
  3206 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  3207 attributes; there is also a toplevel print command.  This facility is
  3208 just a common case of general context data, which is the preferred way
  3209 for anything more complex than just a list of facts in canonical
  3210 order.
  3211 
  3212 * Isar: command 'declaration' augments a local theory by generic
  3213 declaration functions written in ML.  This enables arbitrary content
  3214 being added to the context, depending on a morphism that tells the
  3215 difference of the original declaration context wrt. the application
  3216 context encountered later on.
  3217 
  3218 * Isar: proper interfaces for simplification procedures.  Command
  3219 'simproc_setup' declares named simprocs (with match patterns, and body
  3220 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  3221 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  3222 
  3223 * Isar: an extra pair of brackets around attribute declarations
  3224 abbreviates a theorem reference involving an internal dummy fact,
  3225 which will be ignored later --- only the effect of the attribute on
  3226 the background context will persist.  This form of in-place
  3227 declarations is particularly useful with commands like 'declare' and
  3228 'using', for example ``have A using [[simproc a]] by simp''.
  3229 
  3230 * Isar: method "assumption" (and implicit closing of subproofs) now
  3231 takes simple non-atomic goal assumptions into account: after applying
  3232 an assumption as a rule the resulting subgoals are solved by atomic
  3233 assumption steps.  This is particularly useful to finish 'obtain'
  3234 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  3235 without referring to the original premise "!!x. P x ==> thesis" in the
  3236 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  3237 more permissive.
  3238 
  3239 * Isar: implicit use of prems from the Isar proof context is
  3240 considered a legacy feature.  Common applications like ``have A .''
  3241 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  3242 referencing facts explicitly here improves readability and
  3243 maintainability of proof texts.
  3244 
  3245 * Isar: improper proof element 'guess' is like 'obtain', but derives
  3246 the obtained context from the course of reasoning!  For example:
  3247 
  3248   assume "EX x y. A x & B y"   -- "any previous fact"
  3249   then guess x and y by clarify
  3250 
  3251 This technique is potentially adventurous, depending on the facts and
  3252 proof tools being involved here.
  3253 
  3254 * Isar: known facts from the proof context may be specified as literal
  3255 propositions, using ASCII back-quote syntax.  This works wherever
  3256 named facts used to be allowed so far, in proof commands, proof
  3257 methods, attributes etc.  Literal facts are retrieved from the context
  3258 according to unification of type and term parameters.  For example,
  3259 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  3260 theorems in the current context, then these are valid literal facts:
  3261 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  3262 
  3263 There is also a proof method "fact" which does the same composition
  3264 for explicit goal states, e.g. the following proof texts coincide with
  3265 certain special cases of literal facts:
  3266 
  3267   have "A" by fact                 ==  note `A`
  3268   have "A ==> B" by fact           ==  note `A ==> B`
  3269   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  3270   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  3271 
  3272 * Isar: ":" (colon) is no longer a symbolic identifier character in
  3273 outer syntax.  Thus symbolic identifiers may be used without
  3274 additional white space in declarations like this: ``assume *: A''.
  3275 
  3276 * Isar: 'print_facts' prints all local facts of the current context,
  3277 both named and unnamed ones.
  3278 
  3279 * Isar: 'def' now admits simultaneous definitions, e.g.:
  3280 
  3281   def x == "t" and y == "u"
  3282 
  3283 * Isar: added command 'unfolding', which is structurally similar to
  3284 'using', but affects both the goal state and facts by unfolding given
  3285 rewrite rules.  Thus many occurrences of the 'unfold' method or
  3286 'unfolded' attribute may be replaced by first-class proof text.
  3287 
  3288 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  3289 and command 'unfolding' now all support object-level equalities
  3290 (potentially conditional).  The underlying notion of rewrite rule is
  3291 analogous to the 'rule_format' attribute, but *not* that of the
  3292 Simplifier (which is usually more generous).
  3293 
  3294 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  3295 premises of a theorem by n. Useful in conjunction with drule.
  3296 
  3297 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  3298 method expression within a sandbox consisting of the first N
  3299 sub-goals, which need to exist.  For example, ``simp_all [3]''
  3300 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  3301 simplifies all new goals that emerge from applying rule foo to the
  3302 originally first one.
  3303 
  3304 * Isar: schematic goals are no longer restricted to higher-order
  3305 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  3306 expected.
  3307 
  3308 * Isar: the conclusion of a long theorem statement is now either
  3309 'shows' (a simultaneous conjunction, as before), or 'obtains'
  3310 (essentially a disjunction of cases with local parameters and
  3311 assumptions).  The latter allows to express general elimination rules
  3312 adequately; in this notation common elimination rules look like this:
  3313 
  3314   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  3315     assumes "EX x. P x"
  3316     obtains x where "P x"
  3317 
  3318   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  3319     assumes "A & B"
  3320     obtains A and B
  3321 
  3322   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  3323     assumes "A | B"
  3324     obtains
  3325       A
  3326     | B
  3327 
  3328 The subsequent classical rules even refer to the formal "thesis"
  3329 explicitly:
  3330 
  3331   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  3332     obtains "~ thesis"
  3333 
  3334   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  3335     obtains "thesis ==> something"
  3336 
  3337 The actual proof of an 'obtains' statement is analogous to that of the
  3338 Isar proof element 'obtain', only that there may be several cases.
  3339 Optional case names may be specified in parentheses; these will be
  3340 available both in the present proof and as annotations in the
  3341 resulting rule, for later use with the 'cases' method (cf. attribute
  3342 case_names).
  3343 
  3344 * Isar: the assumptions of a long theorem statement are available as
  3345 "assms" fact in the proof context.  This is more appropriate than the
  3346 (historical) "prems", which refers to all assumptions of the current
  3347 context, including those from the target locale, proof body etc.
  3348 
  3349 * Isar: 'print_statement' prints theorems from the current theory or
  3350 proof context in long statement form, according to the syntax of a
  3351 top-level lemma.
  3352 
  3353 * Isar: 'obtain' takes an optional case name for the local context
  3354 introduction rule (default "that").
  3355 
  3356 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  3357 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  3358 to occur.
  3359 
  3360 * Pure: syntax "CONST name" produces a fully internalized constant
  3361 according to the current context.  This is particularly useful for
  3362 syntax translations that should refer to internal constant
  3363 representations independently of name spaces.
  3364 
  3365 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  3366 instead of "FOO ". This allows multiple binder declarations to coexist
  3367 in the same context.  INCOMPATIBILITY.
  3368 
  3369 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  3370 primitive that also works in a locale context (both for constants and
  3371 fixed variables). Type declaration and internal syntactic representation
  3372 of given constants retrieved from the context. Likewise, the
  3373 'no_notation' command allows to remove given syntax annotations from the
  3374 current context.
  3375 
  3376 * Isar/locales: new derived specification elements 'axiomatization',
  3377 'definition', 'abbreviation', which support type-inference, admit
  3378 object-level specifications (equality, equivalence).  See also the
  3379 isar-ref manual.  Examples:
  3380 
  3381   axiomatization
  3382     eq  (infix "===" 50) where
  3383     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  3384 
  3385   definition "f x y = x + y + 1"
  3386   definition g where "g x = f x x"
  3387 
  3388   abbreviation
  3389     neq  (infix "=!=" 50) where
  3390     "x =!= y == ~ (x === y)"
  3391 
  3392 These specifications may be also used in a locale context.  Then the
  3393 constants being introduced depend on certain fixed parameters, and the
  3394 constant name is qualified by the locale base name.  An internal
  3395 abbreviation takes care for convenient input and output, making the
  3396 parameters implicit and using the original short name.  See also
  3397 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  3398 entities from a monomorphic theory.
  3399 
  3400 Presently, abbreviations are only available 'in' a target locale, but
  3401 not inherited by general import expressions.  Also note that
  3402 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  3403 'translations' in common applications.  The "no_abbrevs" print mode
  3404 prevents folding of abbreviations in term output.
  3405 
  3406 Concrete syntax is attached to specified constants in internal form,
  3407 independently of name spaces.  The parse tree representation is
  3408 slightly different -- use 'notation' instead of raw 'syntax', and
  3409 'translations' with explicit "CONST" markup to accommodate this.
  3410 
  3411 * Pure/Isar: unified syntax for new-style specification mechanisms
  3412 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  3413 full type inference and dummy patterns ("_").  For example:
  3414 
  3415   definition "K x _ = x"
  3416 
  3417   inductive conj for A B
  3418   where "A ==> B ==> conj A B"
  3419 
  3420 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  3421 the current context.  Print mode "no_abbrevs" prevents inversion of
  3422 abbreviations on output.
  3423 
  3424 * Isar/locales: improved parameter handling: use of locales "var" and
  3425 "struct" no longer necessary; - parameter renamings are no longer
  3426 required to be injective.  For example, this allows to define
  3427 endomorphisms as locale endom = homom mult mult h.
  3428 
  3429 * Isar/locales: changed the way locales with predicates are defined.
  3430 Instead of accumulating the specification, the imported expression is
  3431 now an interpretation.  INCOMPATIBILITY: different normal form of
  3432 locale expressions.  In particular, in interpretations of locales with
  3433 predicates, goals repesenting already interpreted fragments are not
  3434 removed automatically.  Use methods `intro_locales' and
  3435 `unfold_locales'; see below.
  3436 
  3437 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  3438 provide backward reasoning on locales predicates.  The methods are
  3439 aware of interpretations and discharge corresponding goals.
  3440 `intro_locales' is less aggressive then `unfold_locales' and does not
  3441 unfold predicates to assumptions.
  3442 
  3443 * Isar/locales: the order in which locale fragments are accumulated
  3444 has changed.  This enables to override declarations from fragments due
  3445 to interpretations -- for example, unwanted simp rules.
  3446 
  3447 * Isar/locales: interpretation in theories and proof contexts has been
  3448 extended.  One may now specify (and prove) equations, which are
  3449 unfolded in interpreted theorems.  This is useful for replacing
  3450 defined concepts (constants depending on locale parameters) by
  3451 concepts already existing in the target context.  Example:
  3452 
  3453   interpretation partial_order ["op <= :: [int, int] => bool"]
  3454     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3455 
  3456 Typically, the constant `partial_order.less' is created by a
  3457 definition specification element in the context of locale
  3458 partial_order.
  3459 
  3460 * Method "induct": improved internal context management to support
  3461 local fixes and defines on-the-fly. Thus explicit meta-level
  3462 connectives !!  and ==> are rarely required anymore in inductive goals
  3463 (using object-logic connectives for this purpose has been long
  3464 obsolete anyway). Common proof patterns are explained in
  3465 src/HOL/Induct/Common_Patterns.thy, see also
  3466 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3467 examples.
  3468 
  3469 * Method "induct": improved handling of simultaneous goals. Instead of
  3470 introducing object-level conjunction, the statement is now split into
  3471 several conclusions, while the corresponding symbolic cases are nested
  3472 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3473 see src/HOL/Induct/Common_Patterns.thy, for example.
  3474 
  3475 * Method "induct": mutual induction rules are now specified as a list
  3476 of rule sharing the same induction cases. HOL packages usually provide
  3477 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3478 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3479 mutual induction rules differently, i.e. like this:
  3480 
  3481   (induct rule: foo_bar.inducts)
  3482   (induct set: foo bar)
  3483   (induct pred: foo bar)
  3484   (induct type: foo bar)
  3485 
  3486 The ML function ProjectRule.projections turns old-style rules into the
  3487 new format.
  3488 
  3489 * Method "coinduct": dual of induction, see
  3490 src/HOL/Library/Coinductive_List.thy for various examples.
  3491 
  3492 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3493 considered a legacy feature.
  3494 
  3495 * Attribute "symmetric" produces result with standardized schematic
  3496 variables (index 0).  Potential INCOMPATIBILITY.
  3497 
  3498 * Simplifier: by default the simplifier trace only shows top level
  3499 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3500 default. Thus there is less danger of being flooded by the trace. The
  3501 trace indicates where parts have been suppressed.
  3502   
  3503 * Provers/classical: removed obsolete classical version of elim_format
  3504 attribute; classical elim/dest rules are now treated uniformly when
  3505 manipulating the claset.
  3506 
  3507 * Provers/classical: stricter checks to ensure that supplied intro,
  3508 dest and elim rules are well-formed; dest and elim rules must have at
  3509 least one premise.
  3510 
  3511 * Provers/classical: attributes dest/elim/intro take an optional
  3512 weight argument for the rule (just as the Pure versions).  Weights are
  3513 ignored by automated tools, but determine the search order of single
  3514 rule steps.
  3515 
  3516 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3517 where the body does not mention the bound variable.  Note that dummy
  3518 patterns implicitly depend on their context of bounds, which makes
  3519 "{_. _}" match any set comprehension as expected.  Potential
  3520 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3521 constant "_idtdummy" in the binding position.
  3522 
  3523 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3524 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3525 for example "A -> B" => "Pi A (%_. B)".
  3526 
  3527 * Pure: 'class_deps' command visualizes the subclass relation, using
  3528 the graph browser tool.
  3529 
  3530 * Pure: 'print_theory' now suppresses certain internal declarations by
  3531 default; use '!' option for full details.
  3532 
  3533 
  3534 *** HOL ***
  3535 
  3536 * Method "metis" proves goals by applying the Metis general-purpose
  3537 resolution prover (see also http://gilith.com/software/metis/).
  3538 Examples are in the directory MetisExamples.  WARNING: the
  3539 Isabelle/HOL-Metis integration does not yet work properly with
  3540 multi-threading.
  3541   
  3542 * Command 'sledgehammer' invokes external automatic theorem provers as
  3543 background processes.  It generates calls to the "metis" method if
  3544 successful. These can be pasted into the proof.  Users do not have to
  3545 wait for the automatic provers to return.  WARNING: does not really
  3546 work with multi-threading.
  3547 
  3548 * New "auto_quickcheck" feature tests outermost goal statements for
  3549 potential counter-examples.  Controlled by ML references
  3550 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3551 5000 milliseconds).  Fails silently if statements is outside of
  3552 executable fragment, or any other codgenerator problem occurs.
  3553 
  3554 * New constant "undefined" with axiom "undefined x = undefined".
  3555 
  3556 * Added class "HOL.eq", allowing for code generation with polymorphic
  3557 equality.
  3558 
  3559 * Some renaming of class constants due to canonical name prefixing in
  3560 the new 'class' package:
  3561 
  3562     HOL.abs ~> HOL.abs_class.abs
  3563     HOL.divide ~> HOL.divide_class.divide
  3564     0 ~> HOL.zero_class.zero
  3565     1 ~> HOL.one_class.one
  3566     op + ~> HOL.plus_class.plus
  3567     op - ~> HOL.minus_class.minus
  3568     uminus ~> HOL.minus_class.uminus
  3569     op * ~> HOL.times_class.times
  3570     op < ~> HOL.ord_class.less
  3571     op <= > HOL.ord_class.less_eq
  3572     Nat.power ~> Power.power_class.power
  3573     Nat.size ~> Nat.size_class.size
  3574     Numeral.number_of ~> Numeral.number_class.number_of
  3575     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3576     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3577     Orderings.min ~> Orderings.ord_class.min
  3578     Orderings.max ~> Orderings.ord_class.max
  3579     Divides.op div ~> Divides.div_class.div
  3580     Divides.op mod ~> Divides.div_class.mod
  3581     Divides.op dvd ~> Divides.div_class.dvd
  3582 
  3583 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3584 
  3585 a) User-defined constants using any of the names "plus", "minus",
  3586 "times", "less" or "less_eq". The standard syntax translations for
  3587 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3588 names.
  3589 
  3590 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3591 INCOMPATIBILITY: use more specific names.
  3592 
  3593 c) Permutative equations (e.g. "a + b = b + a")
  3594 Since the change of names also changes the order of terms, permutative
  3595 rewrite rules may get applied in a different order. Experience shows
  3596 that this is rarely the case (only two adaptions in the whole Isabelle
  3597 distribution).  INCOMPATIBILITY: rewrite proofs
  3598 
  3599 d) ML code directly refering to constant names
  3600 This in general only affects hand-written proof tactics, simprocs and
  3601 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3602 Consider using @{const_name} antiquotation.
  3603 
  3604 * New class "default" with associated constant "default".
  3605 
  3606 * Function "sgn" is now overloaded and available on int, real, complex
  3607 (and other numeric types), using class "sgn".  Two possible defs of
  3608 sgn are given as equational assumptions in the classes sgn_if and
  3609 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3610 INCOMPATIBILITY.
  3611 
  3612 * Locale "partial_order" now unified with class "order" (cf. theory
  3613 Orderings), added parameter "less".  INCOMPATIBILITY.
  3614 
  3615 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3616 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3617 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3618 
  3619 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3620 changed order of proof goals in instance proofs.
  3621 
  3622 * The transitivity reasoner for partial and linear orders is set up
  3623 for classes "order" and "linorder".  Instances of the reasoner are available
  3624 in all contexts importing or interpreting the corresponding locales.
  3625 Method "order" invokes the reasoner separately; the reasoner
  3626 is also integrated with the Simplifier as a solver.  Diagnostic
  3627 command 'print_orders' shows the available instances of the reasoner
  3628 in the current context.
  3629 
  3630 * Localized monotonicity predicate in theory "Orderings"; integrated
  3631 lemmas max_of_mono and min_of_mono with this predicate.
  3632 INCOMPATIBILITY.
  3633 
  3634 * Formulation of theorem "dense" changed slightly due to integration
  3635 with new class dense_linear_order.
  3636 
  3637 * Uniform lattice theory development in HOL.
  3638 
  3639     constants "meet" and "join" now named "inf" and "sup"
  3640     constant "Meet" now named "Inf"
  3641 
  3642     classes "meet_semilorder" and "join_semilorder" now named
  3643       "lower_semilattice" and "upper_semilattice"
  3644     class "lorder" now named "lattice"
  3645     class "comp_lat" now named "complete_lattice"
  3646 
  3647     Instantiation of lattice classes allows explicit definitions
  3648     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3649 
  3650   INCOMPATIBILITY.  Theorem renames:
  3651 
  3652     meet_left_le            ~> inf_le1
  3653     meet_right_le           ~> inf_le2
  3654     join_left_le            ~> sup_ge1
  3655     join_right_le           ~> sup_ge2
  3656     meet_join_le            ~> inf_sup_ord
  3657     le_meetI                ~> le_infI
  3658     join_leI                ~> le_supI
  3659     le_meet                 ~> le_inf_iff
  3660     le_join                 ~> ge_sup_conv
  3661     meet_idempotent         ~> inf_idem
  3662     join_idempotent         ~> sup_idem
  3663     meet_comm               ~> inf_commute
  3664     join_comm               ~> sup_commute
  3665     meet_leI1               ~> le_infI1
  3666     meet_leI2               ~> le_infI2
  3667     le_joinI1               ~> le_supI1
  3668     le_joinI2               ~> le_supI2
  3669     meet_assoc              ~> inf_assoc
  3670     join_assoc              ~> sup_assoc
  3671     meet_left_comm          ~> inf_left_commute
  3672     meet_left_idempotent    ~> inf_left_idem
  3673     join_left_comm          ~> sup_left_commute
  3674     join_left_idempotent    ~> sup_left_idem
  3675     meet_aci                ~> inf_aci
  3676     join_aci                ~> sup_aci
  3677     le_def_meet             ~> le_iff_inf
  3678     le_def_join             ~> le_iff_sup
  3679     join_absorp2            ~> sup_absorb2
  3680     join_absorp1            ~> sup_absorb1
  3681     meet_absorp1            ~> inf_absorb1
  3682     meet_absorp2            ~> inf_absorb2
  3683     meet_join_absorp        ~> inf_sup_absorb
  3684     join_meet_absorp        ~> sup_inf_absorb
  3685     distrib_join_le         ~> distrib_sup_le
  3686     distrib_meet_le         ~> distrib_inf_le
  3687 
  3688     add_meet_distrib_left   ~> add_inf_distrib_left
  3689     add_join_distrib_left   ~> add_sup_distrib_left
  3690     is_join_neg_meet        ~> is_join_neg_inf
  3691     is_meet_neg_join        ~> is_meet_neg_sup
  3692     add_meet_distrib_right  ~> add_inf_distrib_right
  3693     add_join_distrib_right  ~> add_sup_distrib_right
  3694     add_meet_join_distribs  ~> add_sup_inf_distribs
  3695     join_eq_neg_meet        ~> sup_eq_neg_inf
  3696     meet_eq_neg_join        ~> inf_eq_neg_sup
  3697     add_eq_meet_join        ~> add_eq_inf_sup
  3698     meet_0_imp_0            ~> inf_0_imp_0
  3699     join_0_imp_0            ~> sup_0_imp_0
  3700     meet_0_eq_0             ~> inf_0_eq_0
  3701     join_0_eq_0             ~> sup_0_eq_0
  3702     neg_meet_eq_join        ~> neg_inf_eq_sup
  3703     neg_join_eq_meet        ~> neg_sup_eq_inf
  3704     join_eq_if              ~> sup_eq_if
  3705 
  3706     mono_meet               ~> mono_inf
  3707     mono_join               ~> mono_sup
  3708     meet_bool_eq            ~> inf_bool_eq
  3709     join_bool_eq            ~> sup_bool_eq
  3710     meet_fun_eq             ~> inf_fun_eq
  3711     join_fun_eq             ~> sup_fun_eq
  3712     meet_set_eq             ~> inf_set_eq
  3713     join_set_eq             ~> sup_set_eq
  3714     meet1_iff               ~> inf1_iff
  3715     meet2_iff               ~> inf2_iff
  3716     meet1I                  ~> inf1I
  3717     meet2I                  ~> inf2I
  3718     meet1D1                 ~> inf1D1
  3719     meet2D1                 ~> inf2D1
  3720     meet1D2                 ~> inf1D2
  3721     meet2D2                 ~> inf2D2
  3722     meet1E                  ~> inf1E
  3723     meet2E                  ~> inf2E
  3724     join1_iff               ~> sup1_iff
  3725     join2_iff               ~> sup2_iff
  3726     join1I1                 ~> sup1I1
  3727     join2I1                 ~> sup2I1
  3728     join1I1                 ~> sup1I1
  3729     join2I2                 ~> sup1I2
  3730     join1CI                 ~> sup1CI
  3731     join2CI                 ~> sup2CI
  3732     join1E                  ~> sup1E
  3733     join2E                  ~> sup2E
  3734 
  3735     is_meet_Meet            ~> is_meet_Inf
  3736     Meet_bool_def           ~> Inf_bool_def
  3737     Meet_fun_def            ~> Inf_fun_def
  3738     Meet_greatest           ~> Inf_greatest
  3739     Meet_lower              ~> Inf_lower
  3740     Meet_set_def            ~> Inf_set_def
  3741 
  3742     Sup_def                 ~> Sup_Inf
  3743     Sup_bool_eq             ~> Sup_bool_def
  3744     Sup_fun_eq              ~> Sup_fun_def
  3745     Sup_set_eq              ~> Sup_set_def
  3746 
  3747     listsp_meetI            ~> listsp_infI
  3748     listsp_meet_eq          ~> listsp_inf_eq
  3749 
  3750     meet_min                ~> inf_min
  3751     join_max                ~> sup_max
  3752 
  3753 * Added syntactic class "size"; overloaded constant "size" now has
  3754 type "'a::size ==> bool"
  3755 
  3756 * Internal reorganisation of `size' of datatypes: size theorems
  3757 "foo.size" are no longer subsumed by "foo.simps" (but are still
  3758 simplification rules by default!); theorems "prod.size" now named
  3759 "*.size".
  3760 
  3761 * Class "div" now inherits from class "times" rather than "type".
  3762 INCOMPATIBILITY.
  3763 
  3764 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  3765 Linorder etc.  have disappeared; operations defined in terms of
  3766 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  3767 
  3768 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  3769 
  3770 * HOL-Word: New extensive library and type for generic, fixed size
  3771 machine words, with arithemtic, bit-wise, shifting and rotating
  3772 operations, reflection into int, nat, and bool lists, automation for
  3773 linear arithmetic (by automatic reflection into nat or int), including
  3774 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  3775 arithmetic type classes, supporting automatic simplification of
  3776 numerals on all operations.
  3777 
  3778 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  3779 
  3780 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  3781 
  3782 * Code generator library theories:
  3783   - Code_Integer represents HOL integers by big integer literals in target
  3784     languages.
  3785   - Code_Char represents HOL characters by character literals in target
  3786     languages.
  3787   - Code_Char_chr like Code_Char, but also offers treatment of character
  3788     codes; includes Code_Integer.
  3789   - Executable_Set allows to generate code for finite sets using lists.
  3790   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  3791     denominator).
  3792   - Executable_Real implements a subset of real numbers, namly those
  3793     representable by rational numbers.
  3794   - Efficient_Nat implements natural numbers by integers, which in general will
  3795     result in higher efficency; pattern matching with 0/Suc is eliminated;
  3796     includes Code_Integer.
  3797   - Code_Index provides an additional datatype index which is mapped to
  3798     target-language built-in integers.
  3799   - Code_Message provides an additional datatype message_string which is isomorphic to
  3800     strings; messages are mapped to target-language strings.
  3801 
  3802 * New package for inductive predicates
  3803 
  3804   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  3805 
  3806     inductive
  3807       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3808       for z_1 :: U_1 and ... and z_n :: U_m
  3809     where
  3810       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3811     | ...
  3812 
  3813   with full support for type-inference, rather than
  3814 
  3815     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3816 
  3817     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3818     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3819 
  3820     inductive "s z_1 ... z_m"
  3821     intros
  3822       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3823       ...
  3824 
  3825   For backward compatibility, there is a wrapper allowing inductive
  3826   sets to be defined with the new package via
  3827 
  3828     inductive_set
  3829       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3830       for z_1 :: U_1 and ... and z_n :: U_m
  3831     where
  3832       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3833     | ...
  3834 
  3835   or
  3836 
  3837     inductive_set
  3838       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3839       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3840       for z_1 :: U_1 and ... and z_n :: U_m
  3841     where
  3842       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3843     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3844     | ...
  3845 
  3846   if the additional syntax "p ..." is required.
  3847 
  3848   Numerous examples can be found in the subdirectories src/HOL/Auth,
  3849   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  3850 
  3851   INCOMPATIBILITIES:
  3852 
  3853   - Since declaration and definition of inductive sets or predicates
  3854     is no longer separated, abbreviations involving the newly
  3855     introduced sets or predicates must be specified together with the
  3856     introduction rules after the 'where' keyword (see above), rather
  3857     than before the actual inductive definition.
  3858 
  3859   - The variables in induction and elimination rules are now
  3860     quantified in the order of their occurrence in the introduction
  3861     rules, rather than in alphabetical order. Since this may break
  3862     some proofs, these proofs either have to be repaired, e.g. by
  3863     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  3864     statements of the form
  3865 
  3866       case (rule_i a_i_1 ... a_i_{k_i})
  3867 
  3868     or the old order of quantification has to be restored by explicitly adding
  3869     meta-level quantifiers in the introduction rules, i.e.
  3870 
  3871       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  3872 
  3873   - The format of the elimination rules is now
  3874 
  3875       p z_1 ... z_m x_1 ... x_n ==>
  3876         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  3877         ==> ... ==> P
  3878 
  3879     for predicates and
  3880 
  3881       (x_1, ..., x_n) : s z_1 ... z_m ==>
  3882         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  3883         ==> ... ==> P
  3884 
  3885     for sets rather than
  3886 
  3887       x : s z_1 ... z_m ==>
  3888         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  3889         ==> ... ==> P
  3890 
  3891     This may require terms in goals to be expanded to n-tuples
  3892     (e.g. using case_tac or simplification with the split_paired_all
  3893     rule) before the above elimination rule is applicable.
  3894 
  3895   - The elimination or case analysis rules for (mutually) inductive
  3896     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  3897     list of rules "p_1_..._p_k.elims" is no longer available.
  3898 
  3899 * New package "function"/"fun" for general recursive functions,
  3900 supporting mutual and nested recursion, definitions in local contexts,
  3901 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  3902 for small examples, and the separate tutorial on the function
  3903 package. The old recdef "package" is still available as before, but
  3904 users are encouraged to use the new package.
  3905 
  3906 * Method "lexicographic_order" automatically synthesizes termination
  3907 relations as lexicographic combinations of size measures. 
  3908 
  3909 * Case-expressions allow arbitrary constructor-patterns (including
  3910 "_") and take their order into account, like in functional
  3911 programming.  Internally, this is translated into nested
  3912 case-expressions; missing cases are added and mapped to the predefined
  3913 constant "undefined". In complicated cases printing may no longer show
  3914 the original input but the internal form. Lambda-abstractions allow
  3915 the same form of pattern matching: "% pat1 => e1 | ..." is an
  3916 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  3917 variable.
  3918 
  3919 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  3920 is an abbreviation for "of_nat :: nat => int". The simplification
  3921 rules for "of_nat" have been changed to work like "int" did
  3922 previously.  Potential INCOMPATIBILITY:
  3923   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  3924   - of_nat_diff and of_nat_mult are no longer default simp rules
  3925 
  3926 * Method "algebra" solves polynomial equations over (semi)rings using
  3927 Groebner bases. The (semi)ring structure is defined by locales and the
  3928 tool setup depends on that generic context. Installing the method for
  3929 a specific type involves instantiating the locale and possibly adding
  3930 declarations for computation on the coefficients.  The method is
  3931 already instantiated for natural numbers and for the axiomatic class
  3932 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  3933 CALCULEMUS 2007 for the general principles underlying this
  3934 architecture of context-aware proof-tools.
  3935 
  3936 * Method "ferrack" implements quantifier elimination over
  3937 special-purpose dense linear orders using locales (analogous to
  3938 "algebra"). The method is already installed for class
  3939 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  3940 rat, etc.
  3941 
  3942 * Former constant "List.op @" now named "List.append".  Use ML
  3943 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  3944 circumvent possible incompatibilities when working on ML level.
  3945 
  3946 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  3947 
  3948 * New function listsum :: 'a list => 'a for arbitrary monoids.
  3949 Special syntax: "SUM x <- xs. f x" (and latex variants)
  3950 
  3951 * New syntax for Haskell-like list comprehension (input only), eg.
  3952 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  3953 
  3954 * The special syntax for function "filter" has changed from [x :
  3955 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  3956 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  3957 
  3958 * [a..b] is now defined for arbitrary linear orders.  It used to be
  3959 defined on nat only, as an abbreviation for [a..<Suc b]
  3960 INCOMPATIBILITY.
  3961 
  3962 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  3963 
  3964 * New functions "sorted" and "sort" in src/HOL/List.thy.
  3965 
  3966 * New lemma collection field_simps (an extension of ring_simps) for
  3967 manipulating (in)equations involving division. Multiplies with all
  3968 denominators that can be proved to be non-zero (in equations) or
  3969 positive/negative (in inequations).
  3970 
  3971 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  3972 have been improved and renamed to ring_simps, group_simps and
  3973 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  3974 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  3975 
  3976 * Theory Library/Commutative_Ring: switched from recdef to function
  3977 package; constants add, mul, pow now curried.  Infix syntax for
  3978 algebraic operations.
  3979 
  3980 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  3981 INCOMPATIBILITY.
  3982 
  3983 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  3984 INCOMPATIBILITY.
  3985 
  3986 * HOL/records: generalised field-update to take a function on the
  3987 field rather than the new value: r(|A := x|) is translated to A_update
  3988 (K x) r The K-combinator that is internally used is called K_record.
  3989 INCOMPATIBILITY: Usage of the plain update functions has to be
  3990 adapted.
  3991  
  3992 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  3993 * x = 0, which are required for a semiring.  Richer structures do not
  3994 inherit from semiring_0 anymore, because this property is a theorem
  3995 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  3996 there is more to prove, but this is mostly trivial.
  3997 
  3998 * Class "recpower" is generalized to arbitrary monoids, not just
  3999 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  4000 commutativity or semiring properties additionally.
  4001 
  4002 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  4003 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  4004 better use 'abbreviation'.
  4005 
  4006 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  4007 
  4008 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  4009 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  4010 significant changes for setting up numeral syntax for types:
  4011   - New constants Numeral.pred and Numeral.succ instead
  4012       of former Numeral.bin_pred and Numeral.bin_succ.
  4013   - Use integer operations instead of bin_add, bin_mult and so on.
  4014   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  4015   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  4016 
  4017 See src/HOL/Integ/IntArith.thy for an example setup.
  4018 
  4019 * Command 'normal_form' computes the normal form of a term that may
  4020 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  4021 produces ``[b, c, a]'' (without proof).  This command is suitable for
  4022 heavy-duty computations because the functions are compiled to ML
  4023 first.  Correspondingly, a method "normalization" is provided.  See
  4024 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  4025 
  4026 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  4027 25 like -->); output depends on the "iff" print_mode, the default is
  4028 "A = B" (with priority 50).
  4029 
  4030 * Relations less (<) and less_eq (<=) are also available on type bool.
  4031 Modified syntax to disallow nesting without explicit parentheses,
  4032 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  4033 INCOMPATIBILITY.
  4034 
  4035 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  4036 
  4037 * Relation composition operator "op O" now has precedence 75 and binds
  4038 stronger than union and intersection. INCOMPATIBILITY.
  4039 
  4040 * The old set interval syntax "{m..n(}" (and relatives) has been
  4041 removed.  Use "{m..<n}" (and relatives) instead.
  4042 
  4043 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  4044 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  4045 ``declare [[simproc del: neq]]''.
  4046 
  4047 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  4048 True/False.
  4049 
  4050 * Theorem Cons_eq_map_conv no longer declared as "simp".
  4051 
  4052 * Theorem setsum_mult renamed to setsum_right_distrib.
  4053 
  4054 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  4055 ``rule'' method.
  4056 
  4057 * Reimplemented methods "sat" and "satx", with several improvements:
  4058 goals no longer need to be stated as "<prems> ==> False", equivalences
  4059 (i.e. "=" on type bool) are handled, variable names of the form
  4060 "lit_<n>" are no longer reserved, significant speedup.
  4061 
  4062 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  4063 zChaff is still supported as well.
  4064 
  4065 * 'inductive' and 'datatype': provide projections of mutual rules,
  4066 bundled as foo_bar.inducts;
  4067 
  4068 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  4069 Library.
  4070 
  4071 * Library: moved theory Accessible_Part to main HOL.
  4072 
  4073 * Library: added theory Coinductive_List of potentially infinite lists
  4074 as greatest fixed-point.
  4075 
  4076 * Library: added theory AssocList which implements (finite) maps as
  4077 association lists.
  4078 
  4079 * Method "evaluation" solves goals (i.e. a boolean expression)
  4080 efficiently by compiling it to ML.  The goal is "proved" (via an
  4081 oracle) if it evaluates to True.
  4082 
  4083 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  4084 also when invoked by the simplifier.  This results in the Simplifier
  4085 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  4086 Configuration option fast_arith_split_limit=0 recovers the old
  4087 behavior.
  4088 
  4089 * Support for hex (0x20) and binary (0b1001) numerals.
  4090 
  4091 * New method: reify eqs (t), where eqs are equations for an
  4092 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  4093 parameter, computes a term s::'b and a list xs::'a list and proves the
  4094 theorem I xs s = t. This is also known as reification or quoting. The
  4095 resulting theorem is applied to the subgoal to substitute t with I xs
  4096 s.  If t is omitted, the subgoal itself is reified.
  4097 
  4098 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  4099 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  4100 where f is supposed to be a computable function (in the sense of code
  4101 generattion). The method uses reify to compute s and xs as above then
  4102 applies corr_thm and uses normalization by evaluation to "prove" f s =
  4103 r and finally gets the theorem t = r, which is again applied to the
  4104 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  4105 
  4106 * Reflection: Automatic reification now handels binding, an example is
  4107 available in src/HOL/ex/ReflectionEx.thy
  4108 
  4109 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  4110 command 'statespace' that is similar to 'record', but introduces an
  4111 abstract specification based on the locale infrastructure instead of
  4112 HOL types.  This leads to extra flexibility in composing state spaces,
  4113 in particular multiple inheritance and renaming of components.
  4114 
  4115 
  4116 *** HOL-Complex ***
  4117 
  4118 * Hyperreal: Functions root and sqrt are now defined on negative real
  4119 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  4120 Nonnegativity side conditions have been removed from many lemmas, so
  4121 that more subgoals may now be solved by simplification; potential
  4122 INCOMPATIBILITY.
  4123 
  4124 * Real: new type classes formalize real normed vector spaces and
  4125 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  4126 and norm :: 'a => real.
  4127 
  4128 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  4129 reals into other types. The overloaded constant Reals :: 'a set is now
  4130 defined as range of_real; potential INCOMPATIBILITY.
  4131 
  4132 * Real: proper support for ML code generation, including 'quickcheck'.
  4133 Reals are implemented as arbitrary precision rationals.
  4134 
  4135 * Hyperreal: Several constants that previously worked only for the
  4136 reals have been generalized, so they now work over arbitrary vector
  4137 spaces. Type annotations may need to be added in some cases; potential
  4138 INCOMPATIBILITY.
  4139 
  4140   Infinitesimal  :: ('a::real_normed_vector) star set
  4141   HFinite        :: ('a::real_normed_vector) star set
  4142   HInfinite      :: ('a::real_normed_vector) star set
  4143   approx         :: ('a::real_normed_vector) star => 'a star => bool
  4144   monad          :: ('a::real_normed_vector) star => 'a star set
  4145   galaxy         :: ('a::real_normed_vector) star => 'a star set
  4146   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  4147   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  4148   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  4149   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  4150   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  4151   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  4152   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  4153   sgn            :: 'a::real_normed_vector => 'a
  4154   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  4155 
  4156 * Complex: Some complex-specific constants are now abbreviations for
  4157 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  4158 hnorm.  Other constants have been entirely removed in favor of the
  4159 polymorphic versions (INCOMPATIBILITY):
  4160 
  4161   approx        <-- capprox
  4162   HFinite       <-- CFinite
  4163   HInfinite     <-- CInfinite
  4164   Infinitesimal <-- CInfinitesimal
  4165   monad         <-- cmonad
  4166   galaxy        <-- cgalaxy
  4167   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  4168   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  4169   (ns)deriv     <-- (ns)cderiv
  4170 
  4171 
  4172 *** HOL-Algebra ***
  4173 
  4174 * Formalisation of ideals and the quotient construction over rings.
  4175 
  4176 * Order and lattice theory no longer based on records.
  4177 INCOMPATIBILITY.
  4178 
  4179 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  4180 greatest_closed.  INCOMPATIBILITY.
  4181 
  4182 * Method algebra is now set up via an attribute.  For examples see
  4183 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  4184 of algebraic structures.
  4185 
  4186 * Renamed theory CRing to Ring.
  4187 
  4188 
  4189 *** HOL-Nominal ***
  4190 
  4191 * Substantial, yet incomplete support for nominal datatypes (binding
  4192 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  4193 src/HOL/Nominal/Examples.  Prospective users should consult
  4194 http://isabelle.in.tum.de/nominal/
  4195 
  4196 
  4197 *** ML ***
  4198 
  4199 * ML basics: just one true type int, which coincides with IntInf.int
  4200 (even on SML/NJ).
  4201 
  4202 * ML within Isar: antiquotations allow to embed statically-checked
  4203 formal entities in the source, referring to the context available at
  4204 compile-time.  For example:
  4205 
  4206 ML {* @{sort "{zero,one}"} *}
  4207 ML {* @{typ "'a => 'b"} *}
  4208 ML {* @{term "%x. x"} *}
  4209 ML {* @{prop "x == y"} *}
  4210 ML {* @{ctyp "'a => 'b"} *}
  4211 ML {* @{cterm "%x. x"} *}
  4212 ML {* @{cprop "x == y"} *}
  4213 ML {* @{thm asm_rl} *}
  4214 ML {* @{thms asm_rl} *}
  4215 ML {* @{type_name c} *}
  4216 ML {* @{type_syntax c} *}
  4217 ML {* @{const_name c} *}
  4218 ML {* @{const_syntax c} *}
  4219 ML {* @{context} *}
  4220 ML {* @{theory} *}
  4221 ML {* @{theory Pure} *}
  4222 ML {* @{theory_ref} *}
  4223 ML {* @{theory_ref Pure} *}
  4224 ML {* @{simpset} *}
  4225 ML {* @{claset} *}
  4226 ML {* @{clasimpset} *}
  4227 
  4228 The same works for sources being ``used'' within an Isar context.
  4229 
  4230 * ML in Isar: improved error reporting; extra verbosity with
  4231 ML_Context.trace enabled.
  4232 
  4233 * Pure/General/table.ML: the join operations now works via exceptions
  4234 DUP/SAME instead of type option. This is simpler in simple cases, and
  4235 admits slightly more efficient complex applications.
  4236 
  4237 * Pure: 'advanced' translation functions (parse_translation etc.) now
  4238 use Context.generic instead of just theory.
  4239 
  4240 * Pure: datatype Context.generic joins theory/Proof.context and
  4241 provides some facilities for code that works in either kind of
  4242 context, notably GenericDataFun for uniform theory and proof data.
  4243 
  4244 * Pure: simplified internal attribute type, which is now always
  4245 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  4246 local (Proof.context) attributes have been discontinued, while
  4247 minimizing code duplication. Thm.rule_attribute and
  4248 Thm.declaration_attribute build canonical attributes; see also structure
  4249 Context for further operations on Context.generic, notably
  4250 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  4251 declarations and definitions.
  4252 
  4253 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  4254 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  4255 init only required for impure data. INCOMPATIBILITY: empty really need
  4256 to be empty (no dependencies on theory content!)
  4257 
  4258 * Pure/kernel: consts certification ignores sort constraints given in
  4259 signature declarations. (This information is not relevant to the
  4260 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  4261 potential INCOMPATIBILITY.
  4262 
  4263 * Pure: axiomatic type classes are now purely definitional, with
  4264 explicit proofs of class axioms and super class relations performed
  4265 internally. See Pure/axclass.ML for the main internal interfaces --
  4266 notably AxClass.define_class supercedes AxClass.add_axclass, and
  4267 AxClass.axiomatize_class/classrel/arity supersede
  4268 Sign.add_classes/classrel/arities.
  4269 
  4270 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  4271 global/local versions on theory vs. Proof.context have been
  4272 discontinued; Attrib.syntax and Method.syntax have been adapted
  4273 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  4274 attributes, methods, etc.
  4275 
  4276 * Pure: several functions of signature "... -> theory -> theory * ..."
  4277 have been reoriented to "... -> theory -> ... * theory" in order to
  4278 allow natural usage in combination with the ||>, ||>>, |-> and
  4279 fold_map combinators.
  4280 
  4281 * Pure: official theorem names (closed derivations) and additional
  4282 comments (tags) are now strictly separate.  Name hints -- which are
  4283 maintained as tags -- may be attached any time without affecting the
  4284 derivation.
  4285 
  4286 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  4287 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  4288 achieve the old behaviour.
  4289 
  4290 * Pure: the "Goal" constant is now called "prop", supporting a
  4291 slightly more general idea of ``protecting'' meta-level rule
  4292 statements.
  4293 
  4294 * Pure: Logic.(un)varify only works in a global context, which is now
  4295 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  4296 Logic.legacy_(un)varify as temporary workaround.
  4297 
  4298 * Pure: structure Name provides scalable operations for generating
  4299 internal variable names, notably Name.variants etc.  This replaces
  4300 some popular functions from term.ML:
  4301 
  4302   Term.variant		->  Name.variant
  4303   Term.variantlist	->  Name.variant_list
  4304   Term.invent_names	->  Name.invent_list
  4305 
  4306 Note that low-level renaming rarely occurs in new code -- operations
  4307 from structure Variable are used instead (see below).
  4308 
  4309 * Pure: structure Variable provides fundamental operations for proper
  4310 treatment of fixed/schematic variables in a context.  For example,
  4311 Variable.import introduces fixes for schematics of given facts and
  4312 Variable.export reverses the effect (up to renaming) -- this replaces
  4313 various freeze_thaw operations.
  4314 
  4315 * Pure: structure Goal provides simple interfaces for
  4316 init/conclude/finish and tactical prove operations (replacing former
  4317 Tactic.prove).  Goal.prove is the canonical way to prove results
  4318 within a given context; Goal.prove_global is a degraded version for
  4319 theory level goals, including a global Drule.standard.  Note that
  4320 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  4321 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  4322 in a locale context).
  4323 
  4324 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  4325 and type checking (Syntax.check_term etc.), with common combinations
  4326 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  4327 which are considered legacy and await removal.
  4328 
  4329 * Pure/Syntax: generic interfaces for type unchecking
  4330 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  4331 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  4332 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  4333 available for convenience, but refer to the very same operations using
  4334 a mere theory instead of a full context.
  4335 
  4336 * Isar: simplified treatment of user-level errors, using exception
  4337 ERROR of string uniformly.  Function error now merely raises ERROR,
  4338 without any side effect on output channels.  The Isar toplevel takes
  4339 care of proper display of ERROR exceptions.  ML code may use plain
  4340 handle/can/try; cat_error may be used to concatenate errors like this:
  4341 
  4342   ... handle ERROR msg => cat_error msg "..."
  4343 
  4344 Toplevel ML code (run directly or through the Isar toplevel) may be
  4345 embedded into the Isar toplevel with exception display/debug like
  4346 this:
  4347 
  4348   Isar.toplevel (fn () => ...)
  4349 
  4350 INCOMPATIBILITY, removed special transform_error facilities, removed
  4351 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  4352 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  4353 -- use plain ERROR instead.
  4354 
  4355 * Isar: theory setup now has type (theory -> theory), instead of a
  4356 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  4357 
  4358 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  4359 ProofContext.debug/verbose flags.
  4360 
  4361 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  4362 theory before entering a proof state.  Transactions now always see a
  4363 quasi-functional intermediate checkpoint, both in interactive and
  4364 batch mode.
  4365 
  4366 * Isar: simplified interfaces for outer syntax.  Renamed
  4367 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  4368 OuterSyntax.add_parsers -- this functionality is now included in
  4369 OuterSyntax.command etc.  INCOMPATIBILITY.
  4370 
  4371 * Simplifier: the simpset of a running simplification process now
  4372 contains a proof context (cf. Simplifier.the_context), which is the
  4373 very context that the initial simpset has been retrieved from (by
  4374 simpset_of/local_simpset_of).  Consequently, all plug-in components
  4375 (solver, looper etc.) may depend on arbitrary proof data.
  4376 
  4377 * Simplifier.inherit_context inherits the proof context (plus the
  4378 local bounds) of the current simplification process; any simproc
  4379 etc. that calls the Simplifier recursively should do this!  Removed
  4380 former Simplifier.inherit_bounds, which is already included here --
  4381 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  4382 specify an explicit context using Simplifier.context/theory_context.
  4383 
  4384 * Simplifier/Classical Reasoner: more abstract interfaces
  4385 change_simpset/claset for modifying the simpset/claset reference of a
  4386 theory; raw versions simpset/claset_ref etc. have been discontinued --
  4387 INCOMPATIBILITY.
  4388 
  4389 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  4390 "Trueprop" etc.
  4391 
  4392 
  4393 *** System ***
  4394 
  4395 * settings: the default heap location within ISABELLE_HOME_USER now
  4396 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  4397 Isabelle installations.
  4398 
  4399 * isabelle-process: option -S (secure mode) disables some critical
  4400 operations, notably runtime compilation and evaluation of ML source
  4401 code.
  4402 
  4403 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  4404 
  4405 * Support for parallel execution, using native multicore support of
  4406 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  4407 independent theories, according to the given theory header
  4408 specifications. The maximum number of worker threads is specified via
  4409 usedir option -M or the "max-threads" setting in Proof General. A
  4410 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  4411 to 6 on a 8-core machine.  User-code needs to observe certain
  4412 guidelines for thread-safe programming, see appendix A in the Isar
  4413 Implementation manual.
  4414 
  4415 
  4416 
  4417 New in Isabelle2005 (October 2005)
  4418 ----------------------------------
  4419 
  4420 *** General ***
  4421 
  4422 * Theory headers: the new header syntax for Isar theories is
  4423 
  4424   theory <name>
  4425   imports <theory1> ... <theoryN>
  4426   uses <file1> ... <fileM>
  4427   begin
  4428 
  4429 where the 'uses' part is optional.  The previous syntax
  4430 
  4431   theory <name> = <theory1> + ... + <theoryN>:
  4432 
  4433 will disappear in the next release.  Use isatool fixheaders to convert
  4434 existing theory files.  Note that there is no change in ancient
  4435 non-Isar theories now, but these will disappear soon.
  4436 
  4437 * Theory loader: parent theories can now also be referred to via
  4438 relative and absolute paths.
  4439 
  4440 * Command 'find_theorems' searches for a list of criteria instead of a
  4441 list of constants. Known criteria are: intro, elim, dest, name:string,
  4442 simp:term, and any term. Criteria can be preceded by '-' to select
  4443 theorems that do not match. Intro, elim, dest select theorems that
  4444 match the current goal, name:s selects theorems whose fully qualified
  4445 name contain s, and simp:term selects all simplification rules whose
  4446 lhs match term.  Any other term is interpreted as pattern and selects
  4447 all theorems matching the pattern. Available in ProofGeneral under
  4448 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  4449 
  4450   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  4451 
  4452 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  4453 matching the current goal as introduction rule and not having "HOL."
  4454 in their name (i.e. not being defined in theory HOL).
  4455 
  4456 * Command 'thms_containing' has been discontinued in favour of
  4457 'find_theorems'; INCOMPATIBILITY.
  4458 
  4459 * Communication with Proof General is now 8bit clean, which means that
  4460 Unicode text in UTF-8 encoding may be used within theory texts (both
  4461 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4462 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4463 
  4464   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4465   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4466 
  4467 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4468 Classical Reasoner.  Typical big applications run around 2 times
  4469 faster.
  4470 
  4471 
  4472 *** Document preparation ***
  4473 
  4474 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4475 of raw sources.  Only those symbols that do not require additional
  4476 LaTeX packages (depending on comments in isabellesym.sty) are
  4477 displayed properly, everything else is left verbatim.  isatool display
  4478 and isatool print are used as front ends (these are subject to the
  4479 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4480 
  4481 * Command tags control specific markup of certain regions of text,
  4482 notably folding and hiding.  Predefined tags include "theory" (for
  4483 theory begin and end), "proof" for proof commands, and "ML" for
  4484 commands involving ML code; the additional tags "visible" and
  4485 "invisible" are unused by default.  Users may give explicit tag
  4486 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4487 interpretation of tags is determined by the LaTeX job during document
  4488 preparation: see option -V of isatool usedir, or options -n and -t of
  4489 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4490 \isadroptag.
  4491 
  4492 Several document versions may be produced at the same time via isatool
  4493 usedir (the generated index.html will link all of them).  Typical
  4494 specifications include ''-V document=theory,proof,ML'' to present
  4495 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4496 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4497 these parts without any formal replacement text.  The Isabelle site
  4498 default settings produce ''document'' and ''outline'' versions as
  4499 specified above.
  4500 
  4501 * Several new antiquotations:
  4502 
  4503   @{term_type term} prints a term with its type annotated;
  4504 
  4505   @{typeof term} prints the type of a term;
  4506 
  4507   @{const const} is the same as @{term const}, but checks that the
  4508   argument is a known logical constant;
  4509 
  4510   @{term_style style term} and @{thm_style style thm} print a term or
  4511   theorem applying a "style" to it
  4512 
  4513   @{ML text}
  4514 
  4515 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4516 definitions, equations, inequations etc., 'concl' printing only the
  4517 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4518 to print the specified premise.  TermStyle.add_style provides an ML
  4519 interface for introducing further styles.  See also the "LaTeX Sugar"
  4520 document practical applications.  The ML antiquotation prints
  4521 type-checked ML expressions verbatim.
  4522 
  4523 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4524 and 'text' support optional locale specification '(in loc)', which
  4525 specifies the default context for interpreting antiquotations.  For
  4526 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4527 
  4528 * Option 'locale=NAME' of antiquotations specifies an alternative
  4529 context interpreting the subsequent argument.  For example: @{thm
  4530 [locale=lattice] inf_assoc}.
  4531 
  4532 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4533 a proof context.
  4534 
  4535 * Proper output of antiquotations for theory commands involving a
  4536 proof context (such as 'locale' or 'theorem (in loc) ...').
  4537 
  4538 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4539 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4540 
  4541 * isatool usedir: new option -C (default true) controls whether option
  4542 -D should include a copy of the original document directory; -C false
  4543 prevents unwanted effects such as copying of administrative CVS data.
  4544 
  4545 
  4546 *** Pure ***
  4547 
  4548 * Considerably improved version of 'constdefs' command.  Now performs
  4549 automatic type-inference of declared constants; additional support for
  4550 local structure declarations (cf. locales and HOL records), see also
  4551 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4552 sequential dependencies of definitions within a single 'constdefs'
  4553 section; moreover, the declared name needs to be an identifier.  If
  4554 all fails, consider to fall back on 'consts' and 'defs' separately.
  4555 
  4556 * Improved indexed syntax and implicit structures.  First of all,
  4557 indexed syntax provides a notational device for subscripted
  4558 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4559 expressions.  Secondly, in a local context with structure
  4560 declarations, number indexes \<^sub>n or the empty index (default
  4561 number 1) refer to a certain fixed variable implicitly; option
  4562 show_structs controls printing of implicit structures.  Typical
  4563 applications of these concepts involve record types and locales.
  4564 
  4565 * New command 'no_syntax' removes grammar declarations (and
  4566 translations) resulting from the given syntax specification, which is
  4567 interpreted in the same manner as for the 'syntax' command.
  4568 
  4569 * 'Advanced' translation functions (parse_translation etc.) may depend
  4570 on the signature of the theory context being presently used for
  4571 parsing/printing, see also isar-ref manual.
  4572 
  4573 * Improved 'oracle' command provides a type-safe interface to turn an
  4574 ML expression of type theory -> T -> term into a primitive rule of
  4575 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4576 is already included here); see also FOL/ex/IffExample.thy;
  4577 INCOMPATIBILITY.
  4578 
  4579 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4580 before); "cI" is no longer bound, use "c.intro" instead.
  4581 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4582 axclasses vs. locales.
  4583 
  4584 * Improved internal renaming of symbolic identifiers -- attach primes
  4585 instead of base 26 numbers.
  4586 
  4587 * New flag show_question_marks controls printing of leading question
  4588 marks in schematic variable names.
  4589 
  4590 * In schematic variable names, *any* symbol following \<^isub> or
  4591 \<^isup> is now treated as part of the base name.  For example, the
  4592 following works without printing of awkward ".0" indexes:
  4593 
  4594   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4595     by simp
  4596 
  4597 * Inner syntax includes (*(*nested*) comments*).
  4598 
  4599 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4600 annotations as "(00...)".
  4601 
  4602 * Clear separation of logical types and nonterminals, where the latter
  4603 may only occur in 'syntax' specifications or type abbreviations.
  4604 Before that distinction was only partially implemented via type class
  4605 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4606 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4607 exotic syntax specifications may require further adaption
  4608 (e.g. Cube/Cube.thy).
  4609 
  4610 * Removed obsolete type class "logic", use the top sort {} instead.
  4611 Note that non-logical types should be declared as 'nonterminals'
  4612 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4613 specifications.
  4614 
  4615 * Attributes 'induct' and 'cases': type or set names may now be
  4616 locally fixed variables as well.
  4617 
  4618 * Simplifier: can now control the depth to which conditional rewriting
  4619 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4620 Limit.
  4621 
  4622 * Simplifier: simplification procedures may now take the current
  4623 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4624 interface), which is very useful for calling the Simplifier
  4625 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4626 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4627 low-level mk_simproc no longer applies Logic.varify internally, to
  4628 allow for use in a context of fixed variables.
  4629 
  4630 * thin_tac now works even if the assumption being deleted contains !!
  4631 or ==>.  More generally, erule now works even if the major premise of
  4632 the elimination rule contains !! or ==>.
  4633 
  4634 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4635 
  4636 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4637 from Pure, which contains all common declarations already.  Both
  4638 theories are defined via plain Isabelle/Isar .thy files.
  4639 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4640 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4641 use isatool fixcpure to adapt your theory and ML sources.
  4642 
  4643 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4644 selections of theorems in named facts via index ranges.
  4645 
  4646 * 'print_theorems': in theory mode, really print the difference
  4647 wrt. the last state (works for interactive theory development only),
  4648 in proof mode print all local facts (cf. 'print_facts');
  4649 
  4650 * 'hide': option '(open)' hides only base names.
  4651 
  4652 * More efficient treatment of intermediate checkpoints in interactive
  4653 theory development.
  4654 
  4655 * Code generator is now invoked via code_module (incremental code
  4656 generation) and code_library (modular code generation, ML structures
  4657 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4658 must be quoted when used as identifiers.
  4659 
  4660 * New 'value' command for reading, evaluating and printing terms using
  4661 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4662 quoted when used as identifier.
  4663 
  4664 
  4665 *** Locales ***
  4666 
  4667 * New commands for the interpretation of locale expressions in
  4668 theories (1), locales (2) and proof contexts (3).  These generate
  4669 proof obligations from the expression specification.  After the
  4670 obligations have been discharged, theorems of the expression are added
  4671 to the theory, target locale or proof context.  The synopsis of the
  4672 commands is a follows:
  4673 
  4674   (1) interpretation expr inst
  4675   (2) interpretation target < expr
  4676   (3) interpret expr inst
  4677 
  4678 Interpretation in theories and proof contexts require a parameter
  4679 instantiation of terms from the current context.  This is applied to
  4680 specifications and theorems of the interpreted expression.
  4681 Interpretation in locales only permits parameter renaming through the
  4682 locale expression.  Interpretation is smart in that interpretations
  4683 that are active already do not occur in proof obligations, neither are
  4684 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4685 inspect active interpretations of a particular locale.  For details,
  4686 see the Isar Reference manual.  Examples can be found in
  4687 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4688 
  4689 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4690 'interpret' instead.
  4691 
  4692 * New context element 'constrains' for adding type constraints to
  4693 parameters.
  4694 
  4695 * Context expressions: renaming of parameters with syntax
  4696 redeclaration.
  4697 
  4698 * Locale declaration: 'includes' disallowed.
  4699 
  4700 * Proper static binding of attribute syntax -- i.e. types / terms /
  4701 facts mentioned as arguments are always those of the locale definition
  4702 context, independently of the context of later invocations.  Moreover,
  4703 locale operations (renaming and type / term instantiation) are applied
  4704 to attribute arguments as expected.
  4705 
  4706 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4707 actual attributes; rare situations may require Attrib.attribute to
  4708 embed those attributes into Attrib.src that lack concrete syntax.
  4709 Attribute implementations need to cooperate properly with the static
  4710 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4711 Attrib.XXX_thm etc. already do the right thing without further
  4712 intervention.  Only unusual applications -- such as "where" or "of"
  4713 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4714 on the context and the facts involved -- may have to assign parsed
  4715 values to argument tokens explicitly.
  4716 
  4717 * Changed parameter management in theorem generation for long goal
  4718 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4719 theorem statement in rare situations.
  4720 
  4721 * Locale inspection command 'print_locale' omits notes elements.  Use
  4722 'print_locale!' to have them included in the output.
  4723 
  4724 
  4725 *** Provers ***
  4726 
  4727 * Provers/hypsubst.ML: improved version of the subst method, for
  4728 single-step rewriting: it now works in bound variable contexts. New is
  4729 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  4730 rewrite a different subterm than the original subst method, which is
  4731 still available as 'simplesubst'.
  4732 
  4733 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  4734 and quasi orders.
  4735 
  4736 * Provers/trancl.ML: new transitivity reasoner for transitive and
  4737 reflexive-transitive closure of relations.
  4738 
  4739 * Provers/blast.ML: new reference depth_limit to make blast's depth
  4740 limit (previously hard-coded with a value of 20) user-definable.
  4741 
  4742 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  4743 is peformed already.  Object-logics merely need to finish their
  4744 initial simpset configuration as before.  INCOMPATIBILITY.
  4745 
  4746 
  4747 *** HOL ***
  4748 
  4749 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  4750 
  4751   syntax (epsilon)
  4752     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  4753 
  4754 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  4755 and x-symbol; use option '-m epsilon' to get it actually printed.
  4756 Moreover, the mathematically important symbolic identifier \<epsilon>
  4757 becomes available as variable, constant etc.  INCOMPATIBILITY,
  4758 
  4759 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  4760 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  4761 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  4762 support corresponding Isar calculations.
  4763 
  4764 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  4765 instead of ":".
  4766 
  4767 * theory SetInterval: changed the syntax for open intervals:
  4768 
  4769   Old       New
  4770   {..n(}    {..<n}
  4771   {)n..}    {n<..}
  4772   {m..n(}   {m..<n}
  4773   {)m..n}   {m<..n}
  4774   {)m..n(}  {m<..<n}
  4775 
  4776 The old syntax is still supported but will disappear in the next
  4777 release.  For conversion use the following Emacs search and replace
  4778 patterns (these are not perfect but work quite well):
  4779 
  4780   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  4781   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  4782 
  4783 * Theory Commutative_Ring (in Library): method comm_ring for proving
  4784 equalities in commutative rings; method 'algebra' provides a generic
  4785 interface.
  4786 
  4787 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  4788 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  4789 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  4790 be a tuple pattern.
  4791 
  4792 Some new syntax forms are available:
  4793 
  4794   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  4795   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  4796   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  4797   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  4798 
  4799 The latter form "\<Sum>x < k. e" used to be based on a separate
  4800 function "Summation", which has been discontinued.
  4801 
  4802 * theory Finite_Set: in structured induction proofs, the insert case
  4803 is now 'case (insert x F)' instead of the old counterintuitive 'case
  4804 (insert F x)'.
  4805 
  4806 * The 'refute' command has been extended to support a much larger
  4807 fragment of HOL, including axiomatic type classes, constdefs and
  4808 typedefs, inductive datatypes and recursion.
  4809 
  4810 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  4811 Requires zChaff with proof generation to be installed.  See
  4812 HOL/ex/SAT_Examples.thy for examples.
  4813 
  4814 * Datatype induction via method 'induct' now preserves the name of the
  4815 induction variable. For example, when proving P(xs::'a list) by
  4816 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  4817 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  4818 in unstructured proof scripts.
  4819 
  4820 * Reworked implementation of records.  Improved scalability for
  4821 records with many fields, avoiding performance problems for type
  4822 inference. Records are no longer composed of nested field types, but
  4823 of nested extension types. Therefore the record type only grows linear
  4824 in the number of extensions and not in the number of fields.  The
  4825 top-level (users) view on records is preserved.  Potential
  4826 INCOMPATIBILITY only in strange cases, where the theory depends on the
  4827 old record representation. The type generated for a record is called
  4828 <record_name>_ext_type.
  4829 
  4830 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  4831 proofs triggered by a record definition or a simproc (if
  4832 quick_and_dirty is enabled).  Definitions of large records can take
  4833 quite long.
  4834 
  4835 New simproc record_upd_simproc for simplification of multiple record
  4836 updates enabled by default.  Moreover, trivial updates are also
  4837 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  4838 occasionally, since simplification is more powerful by default.
  4839 
  4840 * typedef: proper support for polymorphic sets, which contain extra
  4841 type-variables in the term.
  4842 
  4843 * Simplifier: automatically reasons about transitivity chains
  4844 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  4845 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  4846 old proofs break occasionally as simplification may now solve more
  4847 goals than previously.
  4848 
  4849 * Simplifier: converts x <= y into x = y if assumption y <= x is
  4850 present.  Works for all partial orders (class "order"), in particular
  4851 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  4852 just like y <= x.
  4853 
  4854 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  4855 bound variable or a constant then the let is unfolded.  Otherwise
  4856 first a is simplified to b, and then f b is simplified to g. If
  4857 possible we abstract b from g arriving at "let x = b in h x",
  4858 otherwise we unfold the let and arrive at g.  The simproc can be
  4859 enabled/disabled by the reference use_let_simproc.  Potential
  4860 INCOMPATIBILITY since simplification is more powerful by default.
  4861 
  4862 * Classical reasoning: the meson method now accepts theorems as arguments.
  4863 
  4864 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  4865 jobs to provide advice on the provability of subgoals.
  4866 
  4867 * Theory OrderedGroup and Ring_and_Field: various additions and
  4868 improvements to faciliate calculations involving equalities and
  4869 inequalities.
  4870 
  4871 The following theorems have been eliminated or modified
  4872 (INCOMPATIBILITY):
  4873 
  4874   abs_eq             now named abs_of_nonneg
  4875   abs_of_ge_0        now named abs_of_nonneg
  4876   abs_minus_eq       now named abs_of_nonpos
  4877   imp_abs_id         now named abs_of_nonneg
  4878   imp_abs_neg_id     now named abs_of_nonpos
  4879   mult_pos           now named mult_pos_pos
  4880   mult_pos_le        now named mult_nonneg_nonneg
  4881   mult_pos_neg_le    now named mult_nonneg_nonpos
  4882   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  4883   mult_neg           now named mult_neg_neg
  4884   mult_neg_le        now named mult_nonpos_nonpos
  4885 
  4886 * The following lemmas in Ring_and_Field have been added to the simplifier:
  4887      
  4888      zero_le_square
  4889      not_square_less_zero 
  4890 
  4891   The following lemmas have been deleted from Real/RealPow:
  4892   
  4893      realpow_zero_zero
  4894      realpow_two
  4895      realpow_less
  4896      zero_le_power
  4897      realpow_two_le
  4898      abs_realpow_two
  4899      realpow_two_abs     
  4900 
  4901 * Theory Parity: added rules for simplifying exponents.
  4902 
  4903 * Theory List:
  4904 
  4905 The following theorems have been eliminated or modified
  4906 (INCOMPATIBILITY):
  4907 
  4908   list_all_Nil       now named list_all.simps(1)
  4909   list_all_Cons      now named list_all.simps(2)
  4910   list_all_conv      now named list_all_iff
  4911   set_mem_eq         now named mem_iff
  4912 
  4913 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  4914 asymptotic "big O" calculations.  See the notes in BigO.thy.
  4915 
  4916 
  4917 *** HOL-Complex ***
  4918 
  4919 * Theory RealDef: better support for embedding natural numbers and
  4920 integers in the reals.
  4921 
  4922 The following theorems have been eliminated or modified
  4923 (INCOMPATIBILITY):
  4924 
  4925   exp_ge_add_one_self  now requires no hypotheses
  4926   real_of_int_add      reversed direction of equality (use [symmetric])
  4927   real_of_int_minus    reversed direction of equality (use [symmetric])
  4928   real_of_int_diff     reversed direction of equality (use [symmetric])
  4929   real_of_int_mult     reversed direction of equality (use [symmetric])
  4930 
  4931 * Theory RComplete: expanded support for floor and ceiling functions.
  4932 
  4933 * Theory Ln is new, with properties of the natural logarithm
  4934 
  4935 * Hyperreal: There is a new type constructor "star" for making
  4936 nonstandard types.  The old type names are now type synonyms:
  4937 
  4938   hypreal = real star
  4939   hypnat = nat star
  4940   hcomplex = complex star
  4941 
  4942 * Hyperreal: Many groups of similarly-defined constants have been
  4943 replaced by polymorphic versions (INCOMPATIBILITY):
  4944 
  4945   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  4946 
  4947   starset      <-- starsetNat, starsetC
  4948   *s*          <-- *sNat*, *sc*
  4949   starset_n    <-- starsetNat_n, starsetC_n
  4950   *sn*         <-- *sNatn*, *scn*
  4951   InternalSets <-- InternalNatSets, InternalCSets
  4952 
  4953   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  4954   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  4955   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  4956   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  4957   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  4958 
  4959 * Hyperreal: Many type-specific theorems have been removed in favor of
  4960 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  4961 
  4962   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  4963   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  4964   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  4965   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  4966   right_minus <-- hypreal_add_minus
  4967   left_minus <-- {hypreal,hcomplex}_add_minus_left
  4968   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  4969   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  4970   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  4971   mult_1_right <-- hcomplex_mult_one_right
  4972   mult_zero_left <-- hcomplex_mult_zero_left
  4973   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  4974   right_distrib <-- hypnat_add_mult_distrib2
  4975   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  4976   right_inverse <-- hypreal_mult_inverse
  4977   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  4978   order_refl <-- {hypreal,hypnat}_le_refl
  4979   order_trans <-- {hypreal,hypnat}_le_trans
  4980   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  4981   order_less_le <-- {hypreal,hypnat}_less_le
  4982   linorder_linear <-- {hypreal,hypnat}_le_linear
  4983   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  4984   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  4985   add_nonneg_nonneg <-- hypreal_le_add_order
  4986 
  4987 * Hyperreal: Separate theorems having to do with type-specific
  4988 versions of constants have been merged into theorems that apply to the
  4989 new polymorphic constants (INCOMPATIBILITY):
  4990 
  4991   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  4992   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  4993   STAR_Un <-- {STAR,NatStar,STARC}_Un
  4994   STAR_Int <-- {STAR,NatStar,STARC}_Int
  4995   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  4996   STAR_subset <-- {STAR,NatStar,STARC}_subset
  4997   STAR_mem <-- {STAR,NatStar,STARC}_mem
  4998   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  4999   STAR_diff <-- {STAR,STARC}_diff
  5000   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  5001     STARC_hcomplex_of_complex}_image_subset
  5002   starset_n_Un <-- starset{Nat,C}_n_Un
  5003   starset_n_Int <-- starset{Nat,C}_n_Int
  5004   starset_n_Compl <-- starset{Nat,C}_n_Compl
  5005   starset_n_diff <-- starset{Nat,C}_n_diff
  5006   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  5007   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  5008   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  5009   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  5010   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  5011   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  5012   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  5013   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  5014   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  5015   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  5016   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  5017   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  5018   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  5019   starfun_diff <-- starfun{C,RC,CR}_diff
  5020   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  5021   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  5022   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  5023   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  5024   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  5025   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  5026   starfun_Id <-- starfunC_Id
  5027   starfun_approx <-- starfun{Nat,CR}_approx
  5028   starfun_capprox <-- starfun{C,RC}_capprox
  5029   starfun_abs <-- starfunNat_rabs
  5030   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  5031   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  5032   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  5033   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  5034   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  5035   starfun_add_approx <-- starfunCR_add_approx
  5036   starfun_inverse_inverse <-- starfunC_inverse_inverse
  5037   starfun_divide <-- starfun{C,CR,RC}_divide
  5038   starfun_n <-- starfun{Nat,C}_n
  5039   starfun_n_mult <-- starfun{Nat,C}_n_mult
  5040   starfun_n_add <-- starfun{Nat,C}_n_add
  5041   starfun_n_add_minus <-- starfunNat_n_add_minus
  5042   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  5043   starfun_n_minus <-- starfun{Nat,C}_n_minus
  5044   starfun_n_eq <-- starfun{Nat,C}_n_eq
  5045 
  5046   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  5047   star_n_minus <-- {hypreal,hcomplex}_minus
  5048   star_n_diff <-- {hypreal,hcomplex}_diff
  5049   star_n_mult <-- {hypreal,hcomplex}_mult
  5050   star_n_inverse <-- {hypreal,hcomplex}_inverse
  5051   star_n_le <-- {hypreal,hypnat}_le
  5052   star_n_less <-- {hypreal,hypnat}_less
  5053   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  5054   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  5055   star_n_abs <-- hypreal_hrabs
  5056   star_n_divide <-- hcomplex_divide
  5057 
  5058   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  5059   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  5060   star_of_diff <-- hypreal_of_real_diff
  5061   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  5062   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  5063   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  5064   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  5065   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  5066   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  5067   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  5068   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  5069   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  5070   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  5071   star_of_number_of <-- {hypreal,hcomplex}_number_of
  5072   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  5073   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  5074   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  5075   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  5076   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  5077   star_of_power <-- hypreal_of_real_power
  5078   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  5079 
  5080 * Hyperreal: new method "transfer" that implements the transfer
  5081 principle of nonstandard analysis. With a subgoal that mentions
  5082 nonstandard types like "'a star", the command "apply transfer"
  5083 replaces it with an equivalent one that mentions only standard types.
  5084 To be successful, all free variables must have standard types; non-
  5085 standard variables must have explicit universal quantifiers.
  5086 
  5087 * Hyperreal: A theory of Taylor series.
  5088 
  5089 
  5090 *** HOLCF ***
  5091 
  5092 * Discontinued special version of 'constdefs' (which used to support
  5093 continuous functions) in favor of the general Pure one with full
  5094 type-inference.
  5095 
  5096 * New simplification procedure for solving continuity conditions; it
  5097 is much faster on terms with many nested lambda abstractions (cubic
  5098 instead of exponential time).
  5099 
  5100 * New syntax for domain package: selector names are now optional.
  5101 Parentheses should be omitted unless argument is lazy, for example:
  5102 
  5103   domain 'a stream = cons "'a" (lazy "'a stream")
  5104 
  5105 * New command 'fixrec' for defining recursive functions with pattern
  5106 matching; defining multiple functions with mutual recursion is also
  5107 supported.  Patterns may include the constants cpair, spair, up, sinl,
  5108 sinr, or any data constructor defined by the domain package. The given
  5109 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  5110 syntax and examples.
  5111 
  5112 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  5113 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  5114 but the proof obligation additionally includes an admissibility
  5115 requirement. The packages generate instances of class cpo or pcpo,
  5116 with continuity and strictness theorems for Rep and Abs.
  5117 
  5118 * HOLCF: Many theorems have been renamed according to a more standard naming
  5119 scheme (INCOMPATIBILITY):
  5120 
  5121   foo_inject:  "foo$x = foo$y ==> x = y"
  5122   foo_eq:      "(foo$x = foo$y) = (x = y)"
  5123   foo_less:    "(foo$x << foo$y) = (x << y)"
  5124   foo_strict:  "foo$UU = UU"
  5125   foo_defined: "... ==> foo$x ~= UU"
  5126   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  5127 
  5128 
  5129 *** ZF ***
  5130 
  5131 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  5132 including the First Isomorphism Theorem (on quotienting by the kernel
  5133 of a homomorphism).
  5134 
  5135 * ZF/Simplifier: install second copy of type solver that actually
  5136 makes use of TC rules declared to Isar proof contexts (or locales);
  5137 the old version is still required for ML proof scripts.
  5138 
  5139 
  5140 *** Cube ***
  5141 
  5142 * Converted to Isar theory format; use locales instead of axiomatic
  5143 theories.
  5144 
  5145 
  5146 *** ML ***
  5147 
  5148 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  5149 for ||>, ||>>, |>>,
  5150 
  5151 * Pure/library.ML no longer defines its own option datatype, but uses
  5152 that of the SML basis, which has constructors NONE and SOME instead of
  5153 None and Some, as well as exception Option.Option instead of OPTION.
  5154 The functions the, if_none, is_some, is_none have been adapted
  5155 accordingly, while Option.map replaces apsome.
  5156 
  5157 * Pure/library.ML: the exception LIST has been given up in favour of
  5158 the standard exceptions Empty and Subscript, as well as
  5159 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  5160 superceded by the standard hd and tl functions etc.
  5161 
  5162 A number of basic list functions are no longer exported to the ML
  5163 toplevel, as they are variants of predefined functions.  The following
  5164 suggests how one can translate existing code:
  5165 
  5166     rev_append xs ys = List.revAppend (xs, ys)
  5167     nth_elem (i, xs) = List.nth (xs, i)
  5168     last_elem xs = List.last xs
  5169     flat xss = List.concat xss
  5170     seq fs = List.app fs
  5171     partition P xs = List.partition P xs
  5172     mapfilter f xs = List.mapPartial f xs
  5173 
  5174 * Pure/library.ML: several combinators for linear functional
  5175 transformations, notably reverse application and composition:
  5176 
  5177   x |> f                f #> g
  5178   (x, y) |-> f          f #-> g
  5179 
  5180 * Pure/library.ML: introduced/changed precedence of infix operators:
  5181 
  5182   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  5183   infix 2 ?;
  5184   infix 3 o oo ooo oooo;
  5185   infix 4 ~~ upto downto;
  5186 
  5187 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  5188 infix operators.
  5189 
  5190 * Pure/library.ML: natural list combinators fold, fold_rev, and
  5191 fold_map support linear functional transformations and nesting.  For
  5192 example:
  5193 
  5194   fold f [x1, ..., xN] y =
  5195     y |> f x1 |> ... |> f xN
  5196 
  5197   (fold o fold) f [xs1, ..., xsN] y =
  5198     y |> fold f xs1 |> ... |> fold f xsN
  5199 
  5200   fold f [x1, ..., xN] =
  5201     f x1 #> ... #> f xN
  5202 
  5203   (fold o fold) f [xs1, ..., xsN] =
  5204     fold f xs1 #> ... #> fold f xsN
  5205 
  5206 * Pure/library.ML: the following selectors on type 'a option are
  5207 available:
  5208 
  5209   the:               'a option -> 'a  (*partial*)
  5210   these:             'a option -> 'a  where 'a = 'b list
  5211   the_default: 'a -> 'a option -> 'a
  5212   the_list:          'a option -> 'a list
  5213 
  5214 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5215 basic operations for association lists, following natural argument
  5216 order; moreover the explicit equality predicate passed here avoids
  5217 potentially expensive polymorphic runtime equality checks.
  5218 The old functions may be expressed as follows:
  5219 
  5220   assoc = uncurry (AList.lookup (op =))
  5221   assocs = these oo AList.lookup (op =)
  5222   overwrite = uncurry (AList.update (op =)) o swap
  5223 
  5224 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5225 
  5226   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  5227   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  5228 
  5229 replacing make_keylist and keyfilter (occassionally used)
  5230 Naive rewrites:
  5231 
  5232   make_keylist = AList.make
  5233   keyfilter = AList.find (op =)
  5234 
  5235 * eq_fst and eq_snd now take explicit equality parameter, thus
  5236   avoiding eqtypes. Naive rewrites:
  5237 
  5238     eq_fst = eq_fst (op =)
  5239     eq_snd = eq_snd (op =)
  5240 
  5241 * Removed deprecated apl and apr (rarely used).
  5242   Naive rewrites:
  5243 
  5244     apl (n, op) =>>= curry op n
  5245     apr (op, m) =>>= fn n => op (n, m)
  5246 
  5247 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  5248 provides a reasonably efficient light-weight implementation of sets as
  5249 lists.
  5250 
  5251 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  5252 few new operations; existing lookup and update are now curried to
  5253 follow natural argument order (for use with fold etc.);
  5254 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  5255 
  5256 * Pure/General: output via the Isabelle channels of
  5257 writeln/warning/error etc. is now passed through Output.output, with a
  5258 hook for arbitrary transformations depending on the print_mode
  5259 (cf. Output.add_mode -- the first active mode that provides a output
  5260 function wins).  Already formatted output may be embedded into further
  5261 text via Output.raw; the result of Pretty.string_of/str_of and derived
  5262 functions (string_of_term/cterm/thm etc.) is already marked raw to
  5263 accommodate easy composition of diagnostic messages etc.  Programmers
  5264 rarely need to care about Output.output or Output.raw at all, with
  5265 some notable exceptions: Output.output is required when bypassing the
  5266 standard channels (writeln etc.), or in token translations to produce
  5267 properly formatted results; Output.raw is required when capturing
  5268 already output material that will eventually be presented to the user
  5269 a second time.  For the default print mode, both Output.output and
  5270 Output.raw have no effect.
  5271 
  5272 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  5273 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  5274 cumulative results are displayed at the end of a batch session.
  5275 
  5276 * Pure/General: File.sysify_path and File.quote_sysify path have been
  5277 replaced by File.platform_path and File.shell_path (with appropriate
  5278 hooks).  This provides a clean interface for unusual systems where the
  5279 internal and external process view of file names are different.
  5280 
  5281 * Pure: more efficient orders for basic syntactic entities: added
  5282 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  5283 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  5284 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  5285 orders now -- potential INCOMPATIBILITY for code that depends on a
  5286 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  5287 Library.sort_strings on result).
  5288 
  5289 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  5290 fold_types traverse types/terms from left to right, observing natural
  5291 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  5292 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  5293 
  5294 * Pure: name spaces have been refined, with significant changes of the
  5295 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  5296 to extern(_table).  The plain name entry path is superceded by a
  5297 general 'naming' context, which also includes the 'policy' to produce
  5298 a fully qualified name and external accesses of a fully qualified
  5299 name; NameSpace.extend is superceded by context dependent
  5300 Sign.declare_name.  Several theory and proof context operations modify
  5301 the naming context.  Especially note Theory.restore_naming and
  5302 ProofContext.restore_naming to get back to a sane state; note that
  5303 Theory.add_path is no longer sufficient to recover from
  5304 Theory.absolute_path in particular.
  5305 
  5306 * Pure: new flags short_names (default false) and unique_names
  5307 (default true) for controlling output of qualified names.  If
  5308 short_names is set, names are printed unqualified.  If unique_names is
  5309 reset, the name prefix is reduced to the minimum required to achieve
  5310 the original result when interning again, even if there is an overlap
  5311 with earlier declarations.
  5312 
  5313 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  5314 now 'extend', and 'merge' gets an additional Pretty.pp argument
  5315 (useful for printing error messages).  INCOMPATIBILITY.
  5316 
  5317 * Pure: major reorganization of the theory context.  Type Sign.sg and
  5318 Theory.theory are now identified, referring to the universal
  5319 Context.theory (see Pure/context.ML).  Actual signature and theory
  5320 content is managed as theory data.  The old code and interfaces were
  5321 spread over many files and structures; the new arrangement introduces
  5322 considerable INCOMPATIBILITY to gain more clarity:
  5323 
  5324   Context -- theory management operations (name, identity, inclusion,
  5325     parents, ancestors, merge, etc.), plus generic theory data;
  5326 
  5327   Sign -- logical signature and syntax operations (declaring consts,
  5328     types, etc.), plus certify/read for common entities;
  5329 
  5330   Theory -- logical theory operations (stating axioms, definitions,
  5331     oracles), plus a copy of logical signature operations (consts,
  5332     types, etc.); also a few basic management operations (Theory.copy,
  5333     Theory.merge, etc.)
  5334 
  5335 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  5336 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  5337 for convenience -- they merely return the theory.
  5338 
  5339 * Pure: type Type.tsig is superceded by theory in most interfaces.
  5340 
  5341 * Pure: the Isar proof context type is already defined early in Pure
  5342 as Context.proof (note that ProofContext.context and Proof.context are
  5343 aliases, where the latter is the preferred name).  This enables other
  5344 Isabelle components to refer to that type even before Isar is present.
  5345 
  5346 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  5347 typeK, constK, axiomK, oracleK), but provide explicit operations for
  5348 any of these kinds.  For example, Sign.intern typeK is now
  5349 Sign.intern_type, Theory.hide_space Sign.typeK is now
  5350 Theory.hide_types.  Also note that former
  5351 Theory.hide_classes/types/consts are now
  5352 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  5353 internalize their arguments!  INCOMPATIBILITY.
  5354 
  5355 * Pure: get_thm interface (of PureThy and ProofContext) expects
  5356 datatype thmref (with constructors Name and NameSelection) instead of
  5357 plain string -- INCOMPATIBILITY;
  5358 
  5359 * Pure: cases produced by proof methods specify options, where NONE
  5360 means to remove case bindings -- INCOMPATIBILITY in
  5361 (RAW_)METHOD_CASES.
  5362 
  5363 * Pure: the following operations retrieve axioms or theorems from a
  5364 theory node or theory hierarchy, respectively:
  5365 
  5366   Theory.axioms_of: theory -> (string * term) list
  5367   Theory.all_axioms_of: theory -> (string * term) list
  5368   PureThy.thms_of: theory -> (string * thm) list
  5369   PureThy.all_thms_of: theory -> (string * thm) list
  5370 
  5371 * Pure: print_tac now outputs the goal through the trace channel.
  5372 
  5373 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  5374 Reference Toplevel.debug (default false) controls detailed printing
  5375 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  5376 controls execution profiling -- set to 1 for time and 2 for space
  5377 (both increase the runtime).
  5378 
  5379 * Isar session: The initial use of ROOT.ML is now always timed,
  5380 i.e. the log will show the actual process times, in contrast to the
  5381 elapsed wall-clock time that the outer shell wrapper produces.
  5382 
  5383 * Simplifier: improved handling of bound variables (nameless
  5384 representation, avoid allocating new strings).  Simprocs that invoke
  5385 the Simplifier recursively should use Simplifier.inherit_bounds to
  5386 avoid local name clashes.  Failure to do so produces warnings
  5387 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  5388 for further details.
  5389 
  5390 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  5391 bindings for all theorems stored within a given theory; this may help
  5392 in porting non-Isar theories to Isar ones, while keeping ML proof
  5393 scripts for the time being.
  5394 
  5395 * ML operator HTML.with_charset specifies the charset begin used for
  5396 generated HTML files.  For example:
  5397 
  5398   HTML.with_charset "utf-8" use_thy "Hebrew";
  5399   HTML.with_charset "utf-8" use_thy "Chinese";
  5400 
  5401 
  5402 *** System ***
  5403 
  5404 * Allow symlinks to all proper Isabelle executables (Isabelle,
  5405 isabelle, isatool etc.).
  5406 
  5407 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  5408 isatool doc, isatool mkdir, display_drafts etc.).
  5409 
  5410 * isatool usedir: option -f allows specification of the ML file to be
  5411 used by Isabelle; default is ROOT.ML.
  5412 
  5413 * New isatool version outputs the version identifier of the Isabelle
  5414 distribution being used.
  5415 
  5416 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  5417 (containing Boolean satisfiability problems) into Isabelle/HOL
  5418 theories.
  5419 
  5420 
  5421 
  5422 New in Isabelle2004 (April 2004)
  5423 --------------------------------
  5424 
  5425 *** General ***
  5426 
  5427 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  5428   Replaces linorder.ML.
  5429 
  5430 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  5431   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  5432   (\<a>...\<z>), are now considered normal letters, and can therefore
  5433   be used anywhere where an ASCII letter (a...zA...Z) has until
  5434   now. COMPATIBILITY: This obviously changes the parsing of some
  5435   terms, especially where a symbol has been used as a binder, say
  5436   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  5437   as an identifier.  Fix it by inserting a space around former
  5438   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  5439   existing theory and ML files.
  5440 
  5441 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  5442 
  5443 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  5444   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  5445   a normal (but invisible) letter. For multiple letter subscripts repeat
  5446   \<^isub> like this: x\<^isub>1\<^isub>2.
  5447 
  5448 * Pure: There are now sub-/superscripts that can span more than one
  5449   character. Text between \<^bsub> and \<^esub> is set in subscript in
  5450   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  5451   superscript. The new control characters are not identifier parts.
  5452 
  5453 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5454   content of "..." to the latex file instead of \isacntrl... . The "..."
  5455   may consist of any printable characters excluding the end bracket >.
  5456 
  5457 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5458   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5459   declare constants "final", which prevents their being given a definition
  5460   later.  It is useful for constants whose behaviour is fixed axiomatically
  5461   rather than definitionally, such as the meta-logic connectives.
  5462 
  5463 * Pure: 'instance' now handles general arities with general sorts
  5464   (i.e. intersections of classes),
  5465 
  5466 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5467   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5468   It can be changed to alter the colors/layout of generated pages.
  5469 
  5470 
  5471 *** Isar ***
  5472 
  5473 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5474   cut_tac, subgoal_tac and thin_tac:
  5475   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5476     locales are no longer forced to write Isar proof scripts.
  5477     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5478     emulations.
  5479   - INCOMPATIBILITY: names of variables to be instantiated may no
  5480     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5481     This is consistent with the instantiation attribute "where".
  5482 
  5483 * Attributes "where" and "of":
  5484   - Now take type variables of instantiated theorem into account when reading
  5485     the instantiation string.  This fixes a bug that caused instantiated
  5486     theorems to have too special types in some circumstances.
  5487   - "where" permits explicit instantiations of type variables.
  5488 
  5489 * Calculation commands "moreover" and "also" no longer interfere with
  5490   current facts ("this"), admitting arbitrary combinations with "then"
  5491   and derived forms.
  5492 
  5493 * Locales:
  5494   - Goal statements involving the context element "includes" no longer
  5495     generate theorems with internal delta predicates (those ending on
  5496     "_axioms") in the premise.
  5497     Resolve particular premise with <locale>.intro to obtain old form.
  5498   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5499     specification and "includes" elements in goal statement.
  5500   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5501     [intro?] and [elim?] (respectively) by default.
  5502   - Experimental command for instantiation of locales in proof contexts:
  5503         instantiate <label>[<attrs>]: <loc>
  5504     Instantiates locale <loc> and adds all its theorems to the current context
  5505     taking into account their attributes.  Label and attrs are optional
  5506     modifiers, like in theorem declarations.  If present, names of
  5507     instantiated theorems are qualified with <label>, and the attributes
  5508     <attrs> are applied after any attributes these theorems might have already.
  5509       If the locale has assumptions, a chained fact of the form
  5510     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5511     are derived.  The command does not support old-style locales declared
  5512     with "locale (open)".
  5513       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5514 
  5515 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5516   (Isar) contexts.
  5517 
  5518 
  5519 *** HOL ***
  5520 
  5521 * Proof import: new image HOL4 contains the imported library from
  5522   the HOL4 system with about 2500 theorems. It is imported by
  5523   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5524   can be used like any other Isabelle image.  See
  5525   HOL/Import/HOL/README for more information.
  5526 
  5527 * Simplifier:
  5528   - Much improved handling of linear and partial orders.
  5529     Reasoners for linear and partial orders are set up for type classes
  5530     "linorder" and "order" respectively, and are added to the default simpset
  5531     as solvers.  This means that the simplifier can build transitivity chains
  5532     to solve goals from the assumptions.
  5533   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5534     of blast or auto after simplification become unnecessary because the goal
  5535     is solved by simplification already.
  5536 
  5537 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5538     all proved in axiomatic type classes for semirings, rings and fields.
  5539 
  5540 * Numerics:
  5541   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5542     now formalized using the Ring_and_Field theory mentioned above.
  5543   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5544     than before, because now they are set up once in a generic manner.
  5545   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5546     Look for the general versions in Ring_and_Field (and Power if they concern
  5547     exponentiation).
  5548 
  5549 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5550 
  5551 * Records:
  5552   - Record types are now by default printed with their type abbreviation
  5553     instead of the list of all field types. This can be configured via
  5554     the reference "print_record_type_abbr".
  5555   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5556     (not enabled by default).
  5557   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5558     EX x. x = sel r to True (not enabled by default).
  5559   - Tactic "record_split_simp_tac" to split and simplify records added.
  5560 
  5561 * 'specification' command added, allowing for definition by
  5562   specification.  There is also an 'ax_specification' command that
  5563   introduces the new constants axiomatically.
  5564 
  5565 * arith(_tac) is now able to generate counterexamples for reals as well.
  5566 
  5567 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5568 
  5569 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5570   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5571 
  5572 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5573   matrix theory to linear programming.
  5574 
  5575 * Unions and Intersections:
  5576   The latex output syntax of UN and INT has been changed
  5577   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5578   i.e. the index formulae has become a subscript.
  5579   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5580 
  5581 * Unions and Intersections over Intervals:
  5582   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5583   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5584   like in normal math, and corresponding versions for < and for intersection.
  5585 
  5586 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5587   lexicographic dictonary ordering has been added as "lexord".
  5588 
  5589 * ML: the legacy theory structures Int and List have been removed. They had
  5590   conflicted with ML Basis Library structures having the same names.
  5591 
  5592 * 'refute' command added to search for (finite) countermodels.  Only works
  5593   for a fragment of HOL.  The installation of an external SAT solver is
  5594   highly recommended.  See "HOL/Refute.thy" for details.
  5595 
  5596 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5597   formulae under an assignment of free variables to random values.
  5598   In contrast to 'refute', it can deal with inductive datatypes,
  5599   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5600   for examples.
  5601 
  5602 
  5603 *** HOLCF ***
  5604 
  5605 * Streams now come with concatenation and are part of the HOLCF image
  5606 
  5607 
  5608 
  5609 New in Isabelle2003 (May 2003)
  5610 ------------------------------
  5611 
  5612 *** General ***
  5613 
  5614 * Provers/simplifier:
  5615 
  5616   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5617     Assumptions are now subject to complete mutual simplification,
  5618     not just from left to right. The simplifier now preserves
  5619     the order of assumptions.
  5620 
  5621     Potential INCOMPATIBILITY:
  5622 
  5623     -- simp sometimes diverges where the old version did
  5624        not, e.g. invoking simp on the goal
  5625 
  5626         [| P (f x); y = x; f x = f y |] ==> Q
  5627 
  5628        now gives rise to the infinite reduction sequence
  5629 
  5630         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5631 
  5632        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5633        kind of problem.
  5634 
  5635     -- Tactics combining classical reasoner and simplification (such as auto)
  5636        are also affected by this change, because many of them rely on
  5637        simp. They may sometimes diverge as well or yield a different numbers
  5638        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5639        in case of problems. Sometimes subsequent calls to the classical
  5640        reasoner will fail because a preceeding call to the simplifier too
  5641        eagerly simplified the goal, e.g. deleted redundant premises.
  5642 
  5643   - The simplifier trace now shows the names of the applied rewrite rules
  5644 
  5645   - You can limit the number of recursive invocations of the simplifier
  5646     during conditional rewriting (where the simplifie tries to solve the
  5647     conditions before applying the rewrite rule):
  5648     ML "simp_depth_limit := n"
  5649     where n is an integer. Thus you can force termination where previously
  5650     the simplifier would diverge.
  5651 
  5652   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5653 
  5654   - No longer aborts on failed congruence proof.  Instead, the
  5655     congruence is ignored.
  5656 
  5657 * Pure: New generic framework for extracting programs from constructive
  5658   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5659   as HOL/Extraction for some case studies.
  5660 
  5661 * Pure: The main goal of the proof state is no longer shown by default, only
  5662 the subgoals. This behaviour is controlled by a new flag.
  5663    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5664 (ML: Proof.show_main_goal).
  5665 
  5666 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5667 rules whose conclusion matches subgoal 1:
  5668       PG menu: Isabelle/Isar -> Show me -> matching rules
  5669 The rules are ordered by how closely they match the subgoal.
  5670 In particular, rules that solve a subgoal outright are displayed first
  5671 (or rather last, the way they are printed).
  5672 (ML: ProofGeneral.print_intros())
  5673 
  5674 * Pure: New flag trace_unify_fail causes unification to print
  5675 diagnostic information (PG: in trace buffer) when it fails. This is
  5676 useful for figuring out why single step proofs like rule, erule or
  5677 assumption failed.
  5678 
  5679 * Pure: Locale specifications now produce predicate definitions
  5680 according to the body of text (covering assumptions modulo local
  5681 definitions); predicate "loc_axioms" covers newly introduced text,
  5682 while "loc" is cumulative wrt. all included locale expressions; the
  5683 latter view is presented only on export into the global theory
  5684 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5685 on the old view without predicates;
  5686 
  5687 * Pure: predefined locales "var" and "struct" are useful for sharing
  5688 parameters (as in CASL, for example); just specify something like
  5689 ``var x + var y + struct M'' as import;
  5690 
  5691 * Pure: improved thms_containing: proper indexing of facts instead of
  5692 raw theorems; check validity of results wrt. current name space;
  5693 include local facts of proof configuration (also covers active
  5694 locales), cover fixed variables in index; may use "_" in term
  5695 specification; an optional limit for the number of printed facts may
  5696 be given (the default is 40);
  5697 
  5698 * Pure: disallow duplicate fact bindings within new-style theory files
  5699 (batch-mode only);
  5700 
  5701 * Provers: improved induct method: assumptions introduced by case
  5702 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5703 the goal statement); "foo" still refers to all facts collectively;
  5704 
  5705 * Provers: the function blast.overloaded has been removed: all constants
  5706 are regarded as potentially overloaded, which improves robustness in exchange
  5707 for slight decrease in efficiency;
  5708 
  5709 * Provers/linorder: New generic prover for transitivity reasoning over
  5710 linear orders.  Note: this prover is not efficient!
  5711 
  5712 * Isar: preview of problems to finish 'show' now produce an error
  5713 rather than just a warning (in interactive mode);
  5714 
  5715 
  5716 *** HOL ***
  5717 
  5718 * arith(_tac)
  5719 
  5720  - Produces a counter example if it cannot prove a goal.
  5721    Note that the counter example may be spurious if the goal is not a formula
  5722    of quantifier-free linear arithmetic.
  5723    In ProofGeneral the counter example appears in the trace buffer.
  5724 
  5725  - Knows about div k and mod k where k is a numeral of type nat or int.
  5726 
  5727  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  5728    linear arithmetic fails. This takes account of quantifiers and divisibility.
  5729    Presburger arithmetic can also be called explicitly via presburger(_tac).
  5730 
  5731 * simp's arithmetic capabilities have been enhanced a bit: it now
  5732 takes ~= in premises into account (by performing a case split);
  5733 
  5734 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  5735 are distributed over a sum of terms;
  5736 
  5737 * New tactic "trans_tac" and method "trans" instantiate
  5738 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  5739 "<=", "<" and "=").
  5740 
  5741 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  5742 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  5743 
  5744 * 'typedef' command has new option "open" to suppress the set
  5745 definition;
  5746 
  5747 * functions Min and Max on finite sets have been introduced (theory
  5748 Finite_Set);
  5749 
  5750 * attribute [symmetric] now works for relations as well; it turns
  5751 (x,y) : R^-1 into (y,x) : R, and vice versa;
  5752 
  5753 * induct over a !!-quantified statement (say !!x1..xn):
  5754   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  5755 
  5756 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  5757 %x. None. Warning: empty_def now refers to the previously hidden definition
  5758 of the empty set.
  5759 
  5760 * Algebra: formalization of classical algebra.  Intended as base for
  5761 any algebraic development in Isabelle.  Currently covers group theory
  5762 (up to Sylow's theorem) and ring theory (Universal Property of
  5763 Univariate Polynomials).  Contributions welcome;
  5764 
  5765 * GroupTheory: deleted, since its material has been moved to Algebra;
  5766 
  5767 * Complex: new directory of the complex numbers with numeric constants,
  5768 nonstandard complex numbers, and some complex analysis, standard and
  5769 nonstandard (Jacques Fleuriot);
  5770 
  5771 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  5772 
  5773 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  5774 Fleuriot);
  5775 
  5776 * Real/HahnBanach: updated and adapted to locales;
  5777 
  5778 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  5779 Gray and Kramer);
  5780 
  5781 * UNITY: added the Meier-Sanders theory of progress sets;
  5782 
  5783 * MicroJava: bytecode verifier and lightweight bytecode verifier
  5784 as abstract algorithms, instantiated to the JVM;
  5785 
  5786 * Bali: Java source language formalization. Type system, operational
  5787 semantics, axiomatic semantics. Supported language features:
  5788 classes, interfaces, objects,virtual methods, static methods,
  5789 static/instance fields, arrays, access modifiers, definite
  5790 assignment, exceptions.
  5791 
  5792 
  5793 *** ZF ***
  5794 
  5795 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  5796 universe, etc.);
  5797 
  5798 * Main ZF: virtually all theories converted to new-style format;
  5799 
  5800 
  5801 *** ML ***
  5802 
  5803 * Pure: Tactic.prove provides sane interface for internal proofs;
  5804 omits the infamous "standard" operation, so this is more appropriate
  5805 than prove_goalw_cterm in many situations (e.g. in simprocs);
  5806 
  5807 * Pure: improved error reporting of simprocs;
  5808 
  5809 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  5810 up simprocs;
  5811 
  5812 
  5813 *** Document preparation ***
  5814 
  5815 * uses \par instead of \\ for line breaks in theory text. This may
  5816 shift some page breaks in large documents. To get the old behaviour
  5817 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  5818 
  5819 * minimized dependencies of isabelle.sty and isabellesym.sty on
  5820 other packages
  5821 
  5822 * \<euro> now needs package babel/greek instead of marvosym (which
  5823 broke \Rightarrow)
  5824 
  5825 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  5826 textcomp package)
  5827 
  5828 
  5829 
  5830 New in Isabelle2002 (March 2002)
  5831 --------------------------------
  5832 
  5833 *** Document preparation ***
  5834 
  5835 * greatly simplified document preparation setup, including more
  5836 graceful interpretation of isatool usedir -i/-d/-D options, and more
  5837 instructive isatool mkdir; users should basically be able to get
  5838 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  5839 users may run a separate document processing stage manually like this:
  5840 "isatool usedir -D output HOL Test && isatool document Test/output";
  5841 
  5842 * theory dependency graph may now be incorporated into documents;
  5843 isatool usedir -g true will produce session_graph.eps/.pdf for use
  5844 with \includegraphics of LaTeX;
  5845 
  5846 * proper spacing of consecutive markup elements, especially text
  5847 blocks after section headings;
  5848 
  5849 * support bold style (for single symbols only), input syntax is like
  5850 this: "\<^bold>\<alpha>" or "\<^bold>A";
  5851 
  5852 * \<bullet> is now output as bold \cdot by default, which looks much
  5853 better in printed text;
  5854 
  5855 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  5856 note that these symbols are currently unavailable in Proof General /
  5857 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  5858 
  5859 * isatool latex no longer depends on changed TEXINPUTS, instead
  5860 isatool document copies the Isabelle style files to the target
  5861 location;
  5862 
  5863 
  5864 *** Isar ***
  5865 
  5866 * Pure/Provers: improved proof by cases and induction;
  5867   - 'case' command admits impromptu naming of parameters (such as
  5868     "case (Suc n)");
  5869   - 'induct' method divinates rule instantiation from the inductive
  5870     claim; no longer requires excessive ?P bindings for proper
  5871     instantiation of cases;
  5872   - 'induct' method properly enumerates all possibilities of set/type
  5873     rules; as a consequence facts may be also passed through *type*
  5874     rules without further ado;
  5875   - 'induct' method now derives symbolic cases from the *rulified*
  5876     rule (before it used to rulify cases stemming from the internal
  5877     atomized version); this means that the context of a non-atomic
  5878     statement becomes is included in the hypothesis, avoiding the
  5879     slightly cumbersome show "PROP ?case" form;
  5880   - 'induct' may now use elim-style induction rules without chaining
  5881     facts, using ``missing'' premises from the goal state; this allows
  5882     rules stemming from inductive sets to be applied in unstructured
  5883     scripts, while still benefitting from proper handling of non-atomic
  5884     statements; NB: major inductive premises need to be put first, all
  5885     the rest of the goal is passed through the induction;
  5886   - 'induct' proper support for mutual induction involving non-atomic
  5887     rule statements (uses the new concept of simultaneous goals, see
  5888     below);
  5889   - append all possible rule selections, but only use the first
  5890     success (no backtracking);
  5891   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  5892   - undeclared rule case names default to numbers 1, 2, 3, ...;
  5893   - added 'print_induct_rules' (covered by help item in recent Proof
  5894     General versions);
  5895   - moved induct/cases attributes to Pure, methods to Provers;
  5896   - generic method setup instantiated for FOL and HOL;
  5897 
  5898 * Pure: support multiple simultaneous goal statements, for example
  5899 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  5900 meta-level mechanism, this acts as if several individual goals had
  5901 been stated separately; in particular common proof methods need to be
  5902 repeated in order to cover all claims; note that a single elimination
  5903 step is *not* sufficient to establish the two conjunctions, so this
  5904 fails:
  5905 
  5906   assume "A & B" then have A and B ..   (*".." fails*)
  5907 
  5908 better use "obtain" in situations as above; alternative refer to
  5909 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  5910 
  5911 * Pure: proper integration with ``locales''; unlike the original
  5912 version by Florian Kammller, Isar locales package high-level proof
  5913 contexts rather than raw logical ones (e.g. we admit to include
  5914 attributes everywhere); operations on locales include merge and
  5915 rename; support for implicit arguments (``structures''); simultaneous
  5916 type-inference over imports and text; see also HOL/ex/Locales.thy for
  5917 some examples;
  5918 
  5919 * Pure: the following commands have been ``localized'', supporting a
  5920 target locale specification "(in name)": 'lemma', 'theorem',
  5921 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  5922 stored both within the locale and at the theory level (exported and
  5923 qualified by the locale name);
  5924 
  5925 * Pure: theory goals may now be specified in ``long'' form, with
  5926 ad-hoc contexts consisting of arbitrary locale elements. for example
  5927 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  5928 definitions may be given, too); the result is a meta-level rule with
  5929 the context elements being discharged in the obvious way;
  5930 
  5931 * Pure: new proof command 'using' allows to augment currently used
  5932 facts after a goal statement ('using' is syntactically analogous to
  5933 'apply', but acts on the goal's facts only); this allows chained facts
  5934 to be separated into parts given before and after a claim, as in
  5935 ``from a and b have C using d and e <proof>'';
  5936 
  5937 * Pure: renamed "antecedent" case to "rule_context";
  5938 
  5939 * Pure: new 'judgment' command records explicit information about the
  5940 object-logic embedding (used by several tools internally); no longer
  5941 use hard-wired "Trueprop";
  5942 
  5943 * Pure: added 'corollary' command;
  5944 
  5945 * Pure: fixed 'token_translation' command;
  5946 
  5947 * Pure: removed obsolete 'exported' attribute;
  5948 
  5949 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  5950 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  5951 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  5952 
  5953 * Pure: method 'atomize' presents local goal premises as object-level
  5954 statements (atomic meta-level propositions); setup controlled via
  5955 rewrite rules declarations of 'atomize' attribute; example
  5956 application: 'induct' method with proper rule statements in improper
  5957 proof *scripts*;
  5958 
  5959 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  5960 now consider the syntactic context of assumptions, giving a better
  5961 chance to get type-inference of the arguments right (this is
  5962 especially important for locales);
  5963 
  5964 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  5965 mode;
  5966 
  5967 * Pure/obtain: the formal conclusion "thesis", being marked as
  5968 ``internal'', may no longer be reference directly in the text;
  5969 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  5970 situations;
  5971 
  5972 * Pure: generic 'sym' attribute which declares a rule both as pure
  5973 'elim?' and for the 'symmetric' operation;
  5974 
  5975 * Pure: marginal comments ``--'' may now occur just anywhere in the
  5976 text; the fixed correlation with particular command syntax has been
  5977 discontinued;
  5978 
  5979 * Pure: new method 'rules' is particularly well-suited for proof
  5980 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  5981 but often produces more compact proof terms with less detours;
  5982 
  5983 * Pure/Provers/classical: simplified integration with pure rule
  5984 attributes and methods; the classical "intro?/elim?/dest?"
  5985 declarations coincide with the pure ones; the "rule" method no longer
  5986 includes classically swapped intros; "intro" and "elim" methods no
  5987 longer pick rules from the context; also got rid of ML declarations
  5988 AddXIs/AddXEs/AddXDs; all of this has some potential for
  5989 INCOMPATIBILITY;
  5990 
  5991 * Provers/classical: attribute 'swapped' produces classical inversions
  5992 of introduction rules;
  5993 
  5994 * Provers/simplifier: 'simplified' attribute may refer to explicit
  5995 rules instead of full simplifier context; 'iff' attribute handles
  5996 conditional rules;
  5997 
  5998 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  5999 
  6000 * HOL: 'recdef' now fails on unfinished automated proofs, use
  6001 "(permissive)" option to recover old behavior;
  6002 
  6003 * HOL: 'inductive' no longer features separate (collective) attributes
  6004 for 'intros' (was found too confusing);
  6005 
  6006 * HOL: properly declared induction rules less_induct and
  6007 wf_induct_rule;
  6008 
  6009 
  6010 *** HOL ***
  6011 
  6012 * HOL: moved over to sane numeral syntax; the new policy is as
  6013 follows:
  6014 
  6015   - 0 and 1 are polymorphic constants, which are defined on any
  6016   numeric type (nat, int, real etc.);
  6017 
  6018   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  6019   binary representation internally;
  6020 
  6021   - type nat has special constructor Suc, and generally prefers Suc 0
  6022   over 1::nat and Suc (Suc 0) over 2::nat;
  6023 
  6024 This change may cause significant problems of INCOMPATIBILITY; here
  6025 are some hints on converting existing sources:
  6026 
  6027   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  6028   entities, so expressions involving "-" (unary or binary minus) need
  6029   to be spaced properly;
  6030 
  6031   - existing occurrences of "1" may need to be constraint "1::nat" or
  6032   even replaced by Suc 0; similar for old "2";
  6033 
  6034   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  6035 
  6036   - remove all special provisions on numerals in proofs;
  6037 
  6038 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  6039 representation (depends on bin_arith_simps in the default context);
  6040 
  6041 * HOL: symbolic syntax for x^2 (numeral 2);
  6042 
  6043 * HOL: the class of all HOL types is now called "type" rather than
  6044 "term"; INCOMPATIBILITY, need to adapt references to this type class
  6045 in axclass/classes, instance/arities, and (usually rare) occurrences
  6046 in typings (of consts etc.); internally the class is called
  6047 "HOL.type", ML programs should refer to HOLogic.typeS;
  6048 
  6049 * HOL/record package improvements:
  6050   - new derived operations "fields" to build a partial record section,
  6051     "extend" to promote a fixed record to a record scheme, and
  6052     "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*
  6053     declared as simp by default;
  6054   - shared operations ("more", "fields", etc.) now need to be always
  6055     qualified) --- potential INCOMPATIBILITY;
  6056   - removed "make_scheme" operations (use "make" with "extend") --
  6057     INCOMPATIBILITY;
  6058   - removed "more" class (simply use "term") -- INCOMPATIBILITY;
  6059   - provides cases/induct rules for use with corresponding Isar
  6060     methods (for concrete records, record schemes, concrete more
  6061     parts, and schematic more parts -- in that order);
  6062   - internal definitions directly based on a light-weight abstract
  6063     theory of product types over typedef rather than datatype;
  6064 
  6065 * HOL: generic code generator for generating executable ML code from
  6066 specifications; specific support for HOL constructs such as inductive
  6067 datatypes and sets, as well as recursive functions; can be invoked
  6068 via 'generate_code' theory section;
  6069 
  6070 * HOL: canonical cases/induct rules for n-tuples (n = 3..7);
  6071 
  6072 * HOL: consolidated and renamed several theories.  In particular:
  6073         Ord.thy has been absorbed into HOL.thy
  6074         String.thy has been absorbed into List.thy
  6075 
  6076 * HOL: concrete setsum syntax "\<Sum>i:A. b" == "setsum (%i. b) A"
  6077 (beware of argument permutation!);
  6078 
  6079 * HOL: linorder_less_split superseded by linorder_cases;
  6080 
  6081 * HOL/List: "nodups" renamed to "distinct";
  6082 
  6083 * HOL: added "The" definite description operator; move Hilbert's "Eps"
  6084 to peripheral theory "Hilbert_Choice"; some INCOMPATIBILITIES:
  6085   - Ex_def has changed, now need to use some_eq_ex
  6086 
  6087 * HOL: made split_all_tac safe; EXISTING PROOFS MAY FAIL OR LOOP, so
  6088 in this (rare) case use:
  6089 
  6090   delSWrapper "split_all_tac"
  6091   addSbefore ("unsafe_split_all_tac", unsafe_split_all_tac)
  6092 
  6093 * HOL: added safe wrapper "split_conv_tac" to claset; EXISTING PROOFS
  6094 MAY FAIL;
  6095 
  6096 * HOL: introduced f^n = f o ... o f; warning: due to the limits of
  6097 Isabelle's type classes, ^ on functions and relations has too general
  6098 a domain, namely ('a * 'b) set and 'a => 'b; this means that it may be
  6099 necessary to attach explicit type constraints;
  6100 
  6101 * HOL/Relation: the prefix name of the infix "O" has been changed from
  6102 "comp" to "rel_comp"; INCOMPATIBILITY: a few theorems have been
  6103 renamed accordingly (eg "compI" -> "rel_compI").
  6104 
  6105 * HOL: syntax translations now work properly with numerals and records
  6106 expressions;
  6107 
  6108 * HOL: bounded abstraction now uses syntax "%" / "\<lambda>" instead
  6109 of "lam" -- INCOMPATIBILITY;
  6110 
  6111 * HOL: got rid of some global declarations (potential INCOMPATIBILITY
  6112 for ML tools): const "()" renamed "Product_Type.Unity", type "unit"
  6113 renamed "Product_Type.unit";
  6114 
  6115 * HOL: renamed rtrancl_into_rtrancl2 to converse_rtrancl_into_rtrancl
  6116 
  6117 * HOL: removed obsolete theorem "optionE" (use "option.exhaust", or
  6118 the "cases" method);
  6119 
  6120 * HOL/GroupTheory: group theory examples including Sylow's theorem (by
  6121 Florian Kammller);
  6122 
  6123 * HOL/IMP: updated and converted to new-style theory format; several
  6124 parts turned into readable document, with proper Isar proof texts and
  6125 some explanations (by Gerwin Klein);
  6126 
  6127 * HOL-Real: added Complex_Numbers (by Gertrud Bauer);
  6128 
  6129 * HOL-Hyperreal is now a logic image;
  6130 
  6131 
  6132 *** HOLCF ***
  6133 
  6134 * Isar: consts/constdefs supports mixfix syntax for continuous
  6135 operations;
  6136 
  6137 * Isar: domain package adapted to new-style theory format, e.g. see
  6138 HOLCF/ex/Dnat.thy;
  6139 
  6140 * theory Lift: proper use of rep_datatype lift instead of ML hacks --
  6141 potential INCOMPATIBILITY; now use plain induct_tac instead of former
  6142 lift.induct_tac, always use UU instead of Undef;
  6143 
  6144 * HOLCF/IMP: updated and converted to new-style theory;
  6145 
  6146 
  6147 *** ZF ***
  6148 
  6149 * Isar: proper integration of logic-specific tools and packages,
  6150 including theory commands '(co)inductive', '(co)datatype',
  6151 'rep_datatype', 'inductive_cases', as well as methods 'ind_cases',
  6152 'induct_tac', 'case_tac', and 'typecheck' (with attribute 'TC');
  6153 
  6154 * theory Main no longer includes AC; for the Axiom of Choice, base
  6155 your theory on Main_ZFC;
  6156 
  6157 * the integer library now covers quotients and remainders, with many
  6158 laws relating division to addition, multiplication, etc.;
  6159 
  6160 * ZF/UNITY: Chandy and Misra's UNITY is now available in ZF, giving a
  6161 typeless version of the formalism;
  6162 
  6163 * ZF/AC, Coind, IMP, Resid: updated and converted to new-style theory
  6164 format;
  6165 
  6166 * ZF/Induct: new directory for examples of inductive definitions,
  6167 including theory Multiset for multiset orderings; converted to
  6168 new-style theory format;
  6169 
  6170 * ZF: many new theorems about lists, ordinals, etc.;
  6171 
  6172 
  6173 *** General ***
  6174 
  6175 * Pure/kernel: meta-level proof terms (by Stefan Berghofer); reference
  6176 variable proof controls level of detail: 0 = no proofs (only oracle
  6177 dependencies), 1 = lemma dependencies, 2 = compact proof terms; see
  6178 also ref manual for further ML interfaces;
  6179 
  6180 * Pure/axclass: removed obsolete ML interface
  6181 goal_subclass/goal_arity;
  6182 
  6183 * Pure/syntax: new token syntax "num" for plain numerals (without "#"
  6184 of "xnum"); potential INCOMPATIBILITY, since -0, -1 etc. are now
  6185 separate tokens, so expressions involving minus need to be spaced
  6186 properly;
  6187 
  6188 * Pure/syntax: support non-oriented infixes, using keyword "infix"
  6189 rather than "infixl" or "infixr";
  6190 
  6191 * Pure/syntax: concrete syntax for dummy type variables admits genuine
  6192 sort constraint specifications in type inference; e.g. "x::_::foo"
  6193 ensures that the type of "x" is of sort "foo" (but not necessarily a
  6194 type variable);
  6195 
  6196 * Pure/syntax: print modes "type_brackets" and "no_type_brackets"
  6197 control output of nested => (types); the default behavior is
  6198 "type_brackets";
  6199 
  6200 * Pure/syntax: builtin parse translation for "_constify" turns valued
  6201 tokens into AST constants;
  6202 
  6203 * Pure/syntax: prefer later declarations of translations and print
  6204 translation functions; potential INCOMPATIBILITY: need to reverse
  6205 multiple declarations for same syntax element constant;
  6206 
  6207 * Pure/show_hyps reset by default (in accordance to existing Isar
  6208 practice);
  6209 
  6210 * Provers/classical: renamed addaltern to addafter, addSaltern to
  6211 addSafter;
  6212 
  6213 * Provers/clasimp: ``iff'' declarations now handle conditional rules
  6214 as well;
  6215 
  6216 * system: tested support for MacOS X; should be able to get Isabelle +
  6217 Proof General to work in a plain Terminal after installing Poly/ML
  6218 (e.g. from the Isabelle distribution area) and GNU bash alone
  6219 (e.g. from http://www.apple.com); full X11, XEmacs and X-Symbol
  6220 support requires further installations, e.g. from
  6221 http://fink.sourceforge.net/);
  6222 
  6223 * system: support Poly/ML 4.1.1 (able to manage larger heaps);
  6224 
  6225 * system: reduced base memory usage by Poly/ML (approx. 20 MB instead
  6226 of 40 MB), cf. ML_OPTIONS;
  6227 
  6228 * system: Proof General keywords specification is now part of the
  6229 Isabelle distribution (see etc/isar-keywords.el);
  6230 
  6231 * system: support for persistent Proof General sessions (refrain from
  6232 outdating all loaded theories on startup); user may create writable
  6233 logic images like this: ``isabelle -q HOL Test'';
  6234 
  6235 * system: smart selection of Isabelle process versus Isabelle
  6236 interface, accommodates case-insensitive file systems (e.g. HFS+); may
  6237 run both "isabelle" and "Isabelle" even if file names are badly
  6238 damaged (executable inspects the case of the first letter of its own
  6239 name); added separate "isabelle-process" and "isabelle-interface";
  6240 
  6241 * system: refrain from any attempt at filtering input streams; no
  6242 longer support ``8bit'' encoding of old isabelle font, instead proper
  6243 iso-latin characters may now be used; the related isatools
  6244 "symbolinput" and "nonascii" have disappeared as well;
  6245 
  6246 * system: removed old "xterm" interface (the print modes "xterm" and
  6247 "xterm_color" are still available for direct use in a suitable
  6248 terminal);
  6249 
  6250 
  6251 
  6252 New in Isabelle99-2 (February 2001)
  6253 -----------------------------------
  6254 
  6255 *** Overview of INCOMPATIBILITIES ***
  6256 
  6257 * HOL: please note that theories in the Library and elsewhere often use the
  6258 new-style (Isar) format; to refer to their theorems in an ML script you must
  6259 bind them to ML identifers by e.g.      val thm_name = thm "thm_name";
  6260 
  6261 * HOL: inductive package no longer splits induction rule aggressively,
  6262 but only as far as specified by the introductions given; the old
  6263 format may be recovered via ML function complete_split_rule or attribute
  6264 'split_rule (complete)';
  6265 
  6266 * HOL: induct renamed to lfp_induct, lfp_Tarski to lfp_unfold,
  6267 gfp_Tarski to gfp_unfold;
  6268 
  6269 * HOL: contrapos, contrapos2 renamed to contrapos_nn, contrapos_pp;
  6270 
  6271 * HOL: infix "dvd" now has priority 50 rather than 70 (because it is a
  6272 relation); infix "^^" has been renamed "``"; infix "``" has been
  6273 renamed "`"; "univalent" has been renamed "single_valued";
  6274 
  6275 * HOL/Real: "rinv" and "hrinv" replaced by overloaded "inverse"
  6276 operation;
  6277 
  6278 * HOLCF: infix "`" has been renamed "$"; the symbol syntax is \<cdot>;
  6279 
  6280 * Isar: 'obtain' no longer declares "that" fact as simp/intro;
  6281 
  6282 * Isar/HOL: method 'induct' now handles non-atomic goals; as a
  6283 consequence, it is no longer monotonic wrt. the local goal context
  6284 (which is now passed through the inductive cases);
  6285 
  6286 * Document preparation: renamed standard symbols \<ll> to \<lless> and
  6287 \<gg> to \<ggreater>;
  6288 
  6289 
  6290 *** Document preparation ***
  6291 
  6292 * \isabellestyle{NAME} selects version of Isabelle output (currently
  6293 available: are "it" for near math-mode best-style output, "sl" for
  6294 slanted text style, and "tt" for plain type-writer; if no
  6295 \isabellestyle command is given, output is according to slanted
  6296 type-writer);
  6297 
  6298 * support sub/super scripts (for single symbols only), input syntax is
  6299 like this: "A\<^sup>*" or "A\<^sup>\<star>";
  6300 
  6301 * some more standard symbols; see Appendix A of the system manual for
  6302 the complete list of symbols defined in isabellesym.sty;
  6303 
  6304 * improved isabelle style files; more abstract symbol implementation
  6305 (should now use \isamath{...} and \isatext{...} in custom symbol
  6306 definitions);
  6307 
  6308 * antiquotation @{goals} and @{subgoals} for output of *dynamic* goals
  6309 state; Note that presentation of goal states does not conform to
  6310 actual human-readable proof documents.  Please do not include goal
  6311 states into document output unless you really know what you are doing!
  6312 
  6313 * proper indentation of antiquoted output with proportional LaTeX
  6314 fonts;
  6315 
  6316 * no_document ML operator temporarily disables LaTeX document
  6317 generation;
  6318 
  6319 * isatool unsymbolize tunes sources for plain ASCII communication;
  6320 
  6321 
  6322 *** Isar ***
  6323 
  6324 * Pure: Isar now suffers initial goal statements to contain unbound
  6325 schematic variables (this does not conform to actual readable proof
  6326 documents, due to unpredictable outcome and non-compositional proof
  6327 checking); users who know what they are doing may use schematic goals
  6328 for Prolog-style synthesis of proven results;
  6329 
  6330 * Pure: assumption method (an implicit finishing) now handles actual
  6331 rules as well;
  6332 
  6333 * Pure: improved 'obtain' --- moved to Pure, insert "that" into
  6334 initial goal, declare "that" only as Pure intro (only for single
  6335 steps); the "that" rule assumption may now be involved in implicit
  6336 finishing, thus ".." becomes a feasible for trivial obtains;
  6337 
  6338 * Pure: default proof step now includes 'intro_classes'; thus trivial
  6339 instance proofs may be performed by "..";
  6340 
  6341 * Pure: ?thesis / ?this / "..." now work for pure meta-level
  6342 statements as well;
  6343 
  6344 * Pure: more robust selection of calculational rules;
  6345 
  6346 * Pure: the builtin notion of 'finished' goal now includes the ==-refl
  6347 rule (as well as the assumption rule);
  6348 
  6349 * Pure: 'thm_deps' command visualizes dependencies of theorems and
  6350 lemmas, using the graph browser tool;
  6351 
  6352 * Pure: predict failure of "show" in interactive mode;
  6353 
  6354 * Pure: 'thms_containing' now takes actual terms as arguments;
  6355 
  6356 * HOL: improved method 'induct' --- now handles non-atomic goals
  6357 (potential INCOMPATIBILITY); tuned error handling;
  6358 
  6359 * HOL: cases and induct rules now provide explicit hints about the
  6360 number of facts to be consumed (0 for "type" and 1 for "set" rules);
  6361 any remaining facts are inserted into the goal verbatim;
  6362 
  6363 * HOL: local contexts (aka cases) may now contain term bindings as
  6364 well; the 'cases' and 'induct' methods new provide a ?case binding for
  6365 the result to be shown in each case;
  6366 
  6367 * HOL: added 'recdef_tc' command;
  6368 
  6369 * isatool convert assists in eliminating legacy ML scripts;
  6370 
  6371 
  6372 *** HOL ***
  6373 
  6374 * HOL/Library: a collection of generic theories to be used together
  6375 with main HOL; the theory loader path already includes this directory
  6376 by default; the following existing theories have been moved here:
  6377 HOL/Induct/Multiset, HOL/Induct/Acc (as Accessible_Part), HOL/While
  6378 (as While_Combinator), HOL/Lex/Prefix (as List_Prefix);
  6379 
  6380 * HOL/Unix: "Some aspects of Unix file-system security", a typical
  6381 modelling and verification task performed in Isabelle/HOL +
  6382 Isabelle/Isar + Isabelle document preparation (by Markus Wenzel).
  6383 
  6384 * HOL/Algebra: special summation operator SUM no longer exists, it has
  6385 been replaced by setsum; infix 'assoc' now has priority 50 (like
  6386 'dvd'); axiom 'one_not_zero' has been moved from axclass 'ring' to
  6387 'domain', this makes the theory consistent with mathematical
  6388 literature;
  6389 
  6390 * HOL basics: added overloaded operations "inverse" and "divide"
  6391 (infix "/"), syntax for generic "abs" operation, generic summation
  6392 operator \<Sum>;
  6393 
  6394 * HOL/typedef: simplified package, provide more useful rules (see also
  6395 HOL/subset.thy);
  6396 
  6397 * HOL/datatype: induction rule for arbitrarily branching datatypes is
  6398 now expressed as a proper nested rule (old-style tactic scripts may
  6399 require atomize_strip_tac to cope with non-atomic premises);
  6400 
  6401 * HOL: renamed theory "Prod" to "Product_Type", renamed "split" rule
  6402 to "split_conv" (old name still available for compatibility);
  6403 
  6404 * HOL: improved concrete syntax for strings (e.g. allows translation
  6405 rules with string literals);
  6406 
  6407 * HOL-Real-Hyperreal: this extends HOL-Real with the hyperreals
  6408  and Fleuriot's mechanization of analysis, including the transcendental
  6409  functions for the reals;
  6410 
  6411 * HOL/Real, HOL/Hyperreal: improved arithmetic simplification;
  6412 
  6413 
  6414 *** CTT ***
  6415 
  6416 * CTT: x-symbol support for Pi, Sigma, -->, : (membership); note that
  6417 "lam" is displayed as TWO lambda-symbols
  6418 
  6419 * CTT: theory Main now available, containing everything (that is, Bool
  6420 and Arith);
  6421 
  6422 
  6423 *** General ***
  6424 
  6425 * Pure: the Simplifier has been implemented properly as a derived rule
  6426 outside of the actual kernel (at last!); the overall performance
  6427 penalty in practical applications is about 50%, while reliability of
  6428 the Isabelle inference kernel has been greatly improved;
  6429 
  6430 * print modes "brackets" and "no_brackets" control output of nested =>
  6431 (types) and ==> (props); the default behaviour is "brackets";
  6432 
  6433 * Provers: fast_tac (and friends) now handle actual object-logic rules
  6434 as assumptions as well;
  6435 
  6436 * system: support Poly/ML 4.0;
  6437 
  6438 * system: isatool install handles KDE version 1 or 2;
  6439 
  6440 
  6441 
  6442 New in Isabelle99-1 (October 2000)
  6443 ----------------------------------
  6444 
  6445 *** Overview of INCOMPATIBILITIES ***
  6446 
  6447 * HOL: simplification of natural numbers is much changed; to partly
  6448 recover the old behaviour (e.g. to prevent n+n rewriting to #2*n)
  6449 issue the following ML commands:
  6450 
  6451   Delsimprocs Nat_Numeral_Simprocs.cancel_numerals;
  6452   Delsimprocs [Nat_Numeral_Simprocs.combine_numerals];
  6453 
  6454 * HOL: simplification no longer dives into case-expressions; this is
  6455 controlled by "t.weak_case_cong" for each datatype t;
  6456 
  6457 * HOL: nat_less_induct renamed to less_induct;
  6458 
  6459 * HOL: systematic renaming of the SOME (Eps) rules, may use isatool
  6460 fixsome to patch .thy and .ML sources automatically;
  6461 
  6462   select_equality  -> some_equality
  6463   select_eq_Ex     -> some_eq_ex
  6464   selectI2EX       -> someI2_ex
  6465   selectI2         -> someI2
  6466   selectI          -> someI
  6467   select1_equality -> some1_equality
  6468   Eps_sym_eq       -> some_sym_eq_trivial
  6469   Eps_eq           -> some_eq_trivial
  6470 
  6471 * HOL: exhaust_tac on datatypes superceded by new generic case_tac;
  6472 
  6473 * HOL: removed obsolete theorem binding expand_if (refer to split_if
  6474 instead);
  6475 
  6476 * HOL: the recursion equations generated by 'recdef' are now called
  6477 f.simps instead of f.rules;
  6478 
  6479 * HOL: qed_spec_mp now also handles bounded ALL as well;
  6480 
  6481 * HOL: 0 is now overloaded, so the type constraint ":: nat" may
  6482 sometimes be needed;
  6483 
  6484 * HOL: the constant for "f``x" is now "image" rather than "op ``";
  6485 
  6486 * HOL: the constant for "f-``x" is now "vimage" rather than "op -``";
  6487 
  6488 * HOL: the disjoint sum is now "<+>" instead of "Plus"; the cartesian
  6489 product is now "<*>" instead of "Times"; the lexicographic product is
  6490 now "<*lex*>" instead of "**";
  6491 
  6492 * HOL: theory Sexp is now in HOL/Induct examples (it used to be part
  6493 of main HOL, but was unused); better use HOL's datatype package;
  6494 
  6495 * HOL: removed "symbols" syntax for constant "override" of theory Map;
  6496 the old syntax may be recovered as follows:
  6497 
  6498   syntax (symbols)
  6499     override  :: "('a ~=> 'b) => ('a ~=> 'b) => ('a ~=> 'b)"
  6500       (infixl "\\<oplus>" 100)
  6501 
  6502 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  6503 
  6504 * HOL/ML: even fewer consts are declared as global (see theories Ord,
  6505 Lfp, Gfp, WF); this only affects ML packages that refer to const names
  6506 internally;
  6507 
  6508 * HOL and ZF: syntax for quotienting wrt an equivalence relation
  6509 changed from A/r to A//r;
  6510 
  6511 * ZF: new treatment of arithmetic (nat & int) may break some old
  6512 proofs;
  6513 
  6514 * Isar: renamed some attributes (RS -> THEN, simplify -> simplified,
  6515 rulify -> rule_format, elimify -> elim_format, ...);
  6516 
  6517 * Isar/Provers: intro/elim/dest attributes changed; renamed
  6518 intro/intro!/intro!! flags to intro!/intro/intro? (in most cases, one
  6519 should have to change intro!! to intro? only); replaced "delrule" by
  6520 "rule del";
  6521 
  6522 * Isar/HOL: renamed "intrs" to "intros" in inductive definitions;
  6523 
  6524 * Provers: strengthened force_tac by using new first_best_tac;
  6525 
  6526 * LaTeX document preparation: several changes of isabelle.sty (see
  6527 lib/texinputs);
  6528 
  6529 
  6530 *** Document preparation ***
  6531 
  6532 * formal comments (text blocks etc.) in new-style theories may now
  6533 contain antiquotations of thm/prop/term/typ/text to be presented
  6534 according to latex print mode; concrete syntax is like this:
  6535 @{term[show_types] "f(x) = a + x"};
  6536 
  6537 * isatool mkdir provides easy setup of Isabelle session directories,
  6538 including proper document sources;
  6539 
  6540 * generated LaTeX sources are now deleted after successful run
  6541 (isatool document -c); may retain a copy somewhere else via -D option
  6542 of isatool usedir;
  6543 
  6544 * isatool usedir -D now lets isatool latex -o sty update the Isabelle
  6545 style files, achieving self-contained LaTeX sources and simplifying
  6546 LaTeX debugging;
  6547 
  6548 * old-style theories now produce (crude) LaTeX output as well;
  6549 
  6550 * browser info session directories are now self-contained (may be put
  6551 on WWW server seperately); improved graphs of nested sessions; removed
  6552 graph for 'all sessions';
  6553 
  6554 * several improvements in isabelle style files; \isabellestyle{it}
  6555 produces fake math mode output; \isamarkupheader is now \section by
  6556 default; see lib/texinputs/isabelle.sty etc.;
  6557 
  6558 
  6559 *** Isar ***
  6560 
  6561 * Isar/Pure: local results and corresponding term bindings are now
  6562 subject to Hindley-Milner polymorphism (similar to ML); this
  6563 accommodates incremental type-inference very nicely;
  6564 
  6565 * Isar/Pure: new derived language element 'obtain' supports
  6566 generalized existence reasoning;
  6567 
  6568 * Isar/Pure: new calculational elements 'moreover' and 'ultimately'
  6569 support accumulation of results, without applying any rules yet;
  6570 useful to collect intermediate results without explicit name
  6571 references, and for use with transitivity rules with more than 2
  6572 premises;
  6573 
  6574 * Isar/Pure: scalable support for case-analysis type proofs: new
  6575 'case' language element refers to local contexts symbolically, as
  6576 produced by certain proof methods; internally, case names are attached
  6577 to theorems as "tags";
  6578 
  6579 * Isar/Pure: theory command 'hide' removes declarations from
  6580 class/type/const name spaces;
  6581 
  6582 * Isar/Pure: theory command 'defs' supports option "(overloaded)" to
  6583 indicate potential overloading;
  6584 
  6585 * Isar/Pure: changed syntax of local blocks from {{ }} to { };
  6586 
  6587 * Isar/Pure: syntax of sorts made 'inner', i.e. have to write
  6588 "{a,b,c}" instead of {a,b,c};
  6589 
  6590 * Isar/Pure now provides its own version of intro/elim/dest
  6591 attributes; useful for building new logics, but beware of confusion
  6592 with the version in Provers/classical;
  6593 
  6594 * Isar/Pure: the local context of (non-atomic) goals is provided via
  6595 case name 'antecedent';
  6596 
  6597 * Isar/Pure: removed obsolete 'transfer' attribute (transfer of thms
  6598 to the current context is now done automatically);
  6599 
  6600 * Isar/Pure: theory command 'method_setup' provides a simple interface
  6601 for definining proof methods in ML;
  6602 
  6603 * Isar/Provers: intro/elim/dest attributes changed; renamed
  6604 intro/intro!/intro!! flags to intro!/intro/intro? (INCOMPATIBILITY, in
  6605 most cases, one should have to change intro!! to intro? only);
  6606 replaced "delrule" by "rule del";
  6607 
  6608 * Isar/Provers: new 'hypsubst' method, plain 'subst' method and
  6609 'symmetric' attribute (the latter supercedes [RS sym]);
  6610 
  6611 * Isar/Provers: splitter support (via 'split' attribute and 'simp'
  6612 method modifier); 'simp' method: 'only:' modifier removes loopers as
  6613 well (including splits);
  6614 
  6615 * Isar/Provers: Simplifier and Classical methods now support all kind
  6616 of modifiers used in the past, including 'cong', 'iff', etc.
  6617 
  6618 * Isar/Provers: added 'fastsimp' and 'clarsimp' methods (combination
  6619 of Simplifier and Classical reasoner);
  6620 
  6621 * Isar/HOL: new proof method 'cases' and improved version of 'induct'
  6622 now support named cases; major packages (inductive, datatype, primrec,
  6623 recdef) support case names and properly name parameters;
  6624 
  6625 * Isar/HOL: new transitivity rules for substitution in inequalities --
  6626 monotonicity conditions are extracted to be proven at end of
  6627 calculations;
  6628 
  6629 * Isar/HOL: removed 'case_split' thm binding, should use 'cases' proof
  6630 method anyway;
  6631 
  6632 * Isar/HOL: removed old expand_if = split_if; theorems if_splits =
  6633 split_if split_if_asm; datatype package provides theorems foo.splits =
  6634 foo.split foo.split_asm for each datatype;
  6635 
  6636 * Isar/HOL: tuned inductive package, rename "intrs" to "intros"
  6637 (potential INCOMPATIBILITY), emulation of mk_cases feature for proof
  6638 scripts: new 'inductive_cases' command and 'ind_cases' method; (Note:
  6639 use "(cases (simplified))" method in proper proof texts);
  6640 
  6641 * Isar/HOL: added global 'arith_split' attribute for 'arith' method;
  6642 
  6643 * Isar: names of theorems etc. may be natural numbers as well;
  6644 
  6645 * Isar: 'pr' command: optional arguments for goals_limit and
  6646 ProofContext.prems_limit; no longer prints theory contexts, but only
  6647 proof states;
  6648 
  6649 * Isar: diagnostic commands 'pr', 'thm', 'prop', 'term', 'typ' admit
  6650 additional print modes to be specified; e.g. "pr(latex)" will print
  6651 proof state according to the Isabelle LaTeX style;
  6652 
  6653 * Isar: improved support for emulating tactic scripts, including proof
  6654 methods 'rule_tac' etc., 'cut_tac', 'thin_tac', 'subgoal_tac',
  6655 'rename_tac', 'rotate_tac', 'tactic', and 'case_tac' / 'induct_tac'
  6656 (for HOL datatypes);
  6657 
  6658 * Isar: simplified (more robust) goal selection of proof methods: 1st
  6659 goal, all goals, or explicit goal specifier (tactic emulation); thus
  6660 'proof method scripts' have to be in depth-first order;
  6661 
  6662 * Isar: tuned 'let' syntax: replaced 'as' keyword by 'and';
  6663 
  6664 * Isar: removed 'help' command, which hasn't been too helpful anyway;
  6665 should instead use individual commands for printing items
  6666 (print_commands, print_methods etc.);
  6667 
  6668 * Isar: added 'nothing' --- the empty list of theorems;
  6669 
  6670 
  6671 *** HOL ***
  6672 
  6673 * HOL/MicroJava: formalization of a fragment of Java, together with a
  6674 corresponding virtual machine and a specification of its bytecode
  6675 verifier and a lightweight bytecode verifier, including proofs of
  6676 type-safety; by Gerwin Klein, Tobias Nipkow, David von Oheimb, and
  6677 Cornelia Pusch (see also the homepage of project Bali at
  6678 http://isabelle.in.tum.de/Bali/);
  6679 
  6680 * HOL/Algebra: new theory of rings and univariate polynomials, by
  6681 Clemens Ballarin;
  6682 
  6683 * HOL/NumberTheory: fundamental Theorem of Arithmetic, Chinese
  6684 Remainder Theorem, Fermat/Euler Theorem, Wilson's Theorem, by Thomas M
  6685 Rasmussen;
  6686 
  6687 * HOL/Lattice: fundamental concepts of lattice theory and order
  6688 structures, including duals, properties of bounds versus algebraic
  6689 laws, lattice operations versus set-theoretic ones, the Knaster-Tarski
  6690 Theorem for complete lattices etc.; may also serve as a demonstration
  6691 for abstract algebraic reasoning using axiomatic type classes, and
  6692 mathematics-style proof in Isabelle/Isar; by Markus Wenzel;
  6693 
  6694 * HOL/Prolog: a (bare-bones) implementation of Lambda-Prolog, by David
  6695 von Oheimb;
  6696 
  6697 * HOL/IMPP: extension of IMP with local variables and mutually
  6698 recursive procedures, by David von Oheimb;
  6699 
  6700 * HOL/Lambda: converted into new-style theory and document;
  6701 
  6702 * HOL/ex/Multiquote: example of multiple nested quotations and
  6703 anti-quotations -- basically a generalized version of de-Bruijn
  6704 representation; very useful in avoiding lifting of operations;
  6705 
  6706 * HOL/record: added general record equality rule to simpset; fixed
  6707 select-update simplification procedure to handle extended records as
  6708 well; admit "r" as field name;
  6709 
  6710 * HOL: 0 is now overloaded over the new sort "zero", allowing its use with
  6711 other numeric types and also as the identity of groups, rings, etc.;
  6712 
  6713 * HOL: new axclass plus_ac0 for addition with the AC-laws and 0 as identity.
  6714 Types nat and int belong to this axclass;
  6715 
  6716 * HOL: greatly improved simplification involving numerals of type nat, int, real:
  6717    (i + #8 + j) = Suc k simplifies to  #7 + (i + j) = k
  6718    i*j + k + j*#3*i     simplifies to  #4*(i*j) + k
  6719   two terms #m*u and #n*u are replaced by #(m+n)*u
  6720     (where #m, #n and u can implicitly be 1; this is simproc combine_numerals)
  6721   and the term/formula #m*u+x ~~ #n*u+y simplifies simplifies to #(m-n)+x ~~ y
  6722     or x ~~ #(n-m)+y, where ~~ is one of = < <= or - (simproc cancel_numerals);
  6723 
  6724 * HOL: meson_tac is available (previously in ex/meson.ML); it is a
  6725 powerful prover for predicate logic but knows nothing of clasets; see
  6726 ex/mesontest.ML and ex/mesontest2.ML for example applications;
  6727 
  6728 * HOL: new version of "case_tac" subsumes both boolean case split and
  6729 "exhaust_tac" on datatypes; INCOMPATIBILITY: exhaust_tac no longer
  6730 exists, may define val exhaust_tac = case_tac for ad-hoc portability;
  6731 
  6732 * HOL: simplification no longer dives into case-expressions: only the
  6733 selector expression is simplified, but not the remaining arms; to
  6734 enable full simplification of case-expressions for datatype t, you may
  6735 remove t.weak_case_cong from the simpset, either globally (Delcongs
  6736 [thm"t.weak_case_cong"];) or locally (delcongs [...]).
  6737 
  6738 * HOL/recdef: the recursion equations generated by 'recdef' for
  6739 function 'f' are now called f.simps instead of f.rules; if all
  6740 termination conditions are proved automatically, these simplification
  6741 rules are added to the simpset, as in primrec; rules may be named
  6742 individually as well, resulting in a separate list of theorems for
  6743 each equation;
  6744 
  6745 * HOL/While is a new theory that provides a while-combinator. It
  6746 permits the definition of tail-recursive functions without the
  6747 provision of a termination measure. The latter is necessary once the
  6748 invariant proof rule for while is applied.
  6749 
  6750 * HOL: new (overloaded) notation for the set of elements below/above
  6751 some element: {..u}, {..u(}, {l..}, {)l..}. See theory SetInterval.
  6752 
  6753 * HOL: theorems impI, allI, ballI bound as "strip";
  6754 
  6755 * HOL: new tactic induct_thm_tac: thm -> string -> int -> tactic
  6756 induct_tac th "x1 ... xn" expects th to have a conclusion of the form
  6757 P v1 ... vn and abbreviates res_inst_tac [("v1","x1"),...,("vn","xn")] th;
  6758 
  6759 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  6760 
  6761 * HOL: theory Sexp now in HOL/Induct examples (it used to be part of
  6762 main HOL, but was unused);
  6763 
  6764 * HOL: fewer consts declared as global (e.g. have to refer to
  6765 "Lfp.lfp" instead of "lfp" internally; affects ML packages only);
  6766 
  6767 * HOL: tuned AST representation of nested pairs, avoiding bogus output
  6768 in case of overlap with user translations (e.g. judgements over
  6769 tuples); (note that the underlying logical represenation is still
  6770 bogus);
  6771 
  6772 
  6773 *** ZF ***
  6774 
  6775 * ZF: simplification automatically cancels common terms in arithmetic
  6776 expressions over nat and int;
  6777 
  6778 * ZF: new treatment of nat to minimize type-checking: all operators
  6779 coerce their operands to a natural number using the function natify,
  6780 making the algebraic laws unconditional;
  6781 
  6782 * ZF: as above, for int: operators coerce their operands to an integer
  6783 using the function intify;
  6784 
  6785 * ZF: the integer library now contains many of the usual laws for the
  6786 orderings, including $<=, and monotonicity laws for $+ and $*;
  6787 
  6788 * ZF: new example ZF/ex/NatSum to demonstrate integer arithmetic
  6789 simplification;
  6790 
  6791 * FOL and ZF: AddIffs now available, giving theorems of the form P<->Q
  6792 to the simplifier and classical reasoner simultaneously;
  6793 
  6794 
  6795 *** General ***
  6796 
  6797 * Provers: blast_tac now handles actual object-logic rules as
  6798 assumptions; note that auto_tac uses blast_tac internally as well;
  6799 
  6800 * Provers: new functions rulify/rulify_no_asm: thm -> thm for turning
  6801 outer -->/All/Ball into ==>/!!; qed_spec_mp now uses rulify_no_asm;
  6802 
  6803 * Provers: delrules now handles destruct rules as well (no longer need
  6804 explicit make_elim);
  6805 
  6806 * Provers: Blast_tac now warns of and ignores "weak elimination rules" e.g.
  6807   [| inj ?f;          ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
  6808 use instead the strong form,
  6809   [| inj ?f; ~ ?W ==> ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
  6810 in HOL, FOL and ZF the function cla_make_elim will create such rules
  6811 from destruct-rules;
  6812 
  6813 * Provers: Simplifier.easy_setup provides a fast path to basic
  6814 Simplifier setup for new object-logics;
  6815 
  6816 * Pure: AST translation rules no longer require constant head on LHS;
  6817 
  6818 * Pure: improved name spaces: ambiguous output is qualified; support
  6819 for hiding of names;
  6820 
  6821 * system: smart setup of canonical ML_HOME, ISABELLE_INTERFACE, and
  6822 XSYMBOL_HOME; no longer need to do manual configuration in most
  6823 situations;
  6824 
  6825 * system: compression of ML heaps images may now be controlled via -c
  6826 option of isabelle and isatool usedir (currently only observed by
  6827 Poly/ML);
  6828 
  6829 * system: isatool installfonts may handle X-Symbol fonts as well (very
  6830 useful for remote X11);
  6831 
  6832 * system: provide TAGS file for Isabelle sources;
  6833 
  6834 * ML: infix 'OF' is a version of 'MRS' with more appropriate argument
  6835 order;
  6836 
  6837 * ML: renamed flags Syntax.trace_norm_ast to Syntax.trace_ast; global
  6838 timing flag supersedes proof_timing and Toplevel.trace;
  6839 
  6840 * ML: new combinators |>> and |>>> for incremental transformations
  6841 with secondary results (e.g. certain theory extensions):
  6842 
  6843 * ML: PureThy.add_defs gets additional argument to indicate potential
  6844 overloading (usually false);
  6845 
  6846 * ML: PureThy.add_thms/add_axioms/add_defs now return theorems as
  6847 results;
  6848 
  6849 
  6850 
  6851 New in Isabelle99 (October 1999)
  6852 --------------------------------
  6853 
  6854 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  6855 
  6856 * HOL: The THEN and ELSE parts of conditional expressions (if P then x else y)
  6857 are no longer simplified.  (This allows the simplifier to unfold recursive
  6858 functional programs.)  To restore the old behaviour, declare
  6859 
  6860     Delcongs [if_weak_cong];
  6861 
  6862 * HOL: Removed the obsolete syntax "Compl A"; use -A for set
  6863 complement;
  6864 
  6865 * HOL: the predicate "inj" is now defined by translation to "inj_on";
  6866 
  6867 * HOL/datatype: mutual_induct_tac no longer exists --
  6868   use induct_tac "x_1 ... x_n" instead of mutual_induct_tac ["x_1", ..., "x_n"]
  6869 
  6870 * HOL/typedef: fixed type inference for representing set; type
  6871 arguments now have to occur explicitly on the rhs as type constraints;
  6872 
  6873 * ZF: The con_defs part of an inductive definition may no longer refer
  6874 to constants declared in the same theory;
  6875 
  6876 * HOL, ZF: the function mk_cases, generated by the inductive
  6877 definition package, has lost an argument.  To simplify its result, it
  6878 uses the default simpset instead of a supplied list of theorems.
  6879 
  6880 * HOL/List: the constructors of type list are now Nil and Cons;
  6881 
  6882 * Simplifier: the type of the infix ML functions
  6883         setSSolver addSSolver setSolver addSolver
  6884 is now  simpset * solver -> simpset  where `solver' is a new abstract type
  6885 for packaging solvers. A solver is created via
  6886         mk_solver: string -> (thm list -> int -> tactic) -> solver
  6887 where the string argument is only a comment.
  6888 
  6889 
  6890 *** Proof tools ***
  6891 
  6892 * Provers/Arith/fast_lin_arith.ML contains a functor for creating a
  6893 decision procedure for linear arithmetic. Currently it is used for
  6894 types `nat', `int', and `real' in HOL (see below); it can, should and
  6895 will be instantiated for other types and logics as well.
  6896 
  6897 * The simplifier now accepts rewrite rules with flexible heads, eg
  6898      hom ?f ==> ?f(?x+?y) = ?f ?x + ?f ?y
  6899   They are applied like any rule with a non-pattern lhs, i.e. by first-order
  6900   matching.
  6901 
  6902 
  6903 *** General ***
  6904 
  6905 * New Isabelle/Isar subsystem provides an alternative to traditional
  6906 tactical theorem proving; together with the ProofGeneral/isar user
  6907 interface it offers an interactive environment for developing human
  6908 readable proof documents (Isar == Intelligible semi-automated
  6909 reasoning); for further information see isatool doc isar-ref,
  6910 src/HOL/Isar_examples and http://isabelle.in.tum.de/Isar/
  6911 
  6912 * improved and simplified presentation of theories: better HTML markup
  6913 (including colors), graph views in several sizes; isatool usedir now
  6914 provides a proper interface for user theories (via -P option); actual
  6915 document preparation based on (PDF)LaTeX is available as well (for
  6916 new-style theories only); see isatool doc system for more information;
  6917 
  6918 * native support for Proof General, both for classic Isabelle and
  6919 Isabelle/Isar;
  6920 
  6921 * ML function thm_deps visualizes dependencies of theorems and lemmas,
  6922 using the graph browser tool;
  6923 
  6924 * Isabelle manuals now also available as PDF;
  6925 
  6926 * theory loader rewritten from scratch (may not be fully
  6927 bug-compatible); old loadpath variable has been replaced by show_path,
  6928 add_path, del_path, reset_path functions; new operations such as
  6929 update_thy, touch_thy, remove_thy, use/update_thy_only (see also
  6930 isatool doc ref);
  6931 
  6932 * improved isatool install: option -k creates KDE application icon,
  6933 option -p DIR installs standalone binaries;
  6934 
  6935 * added ML_PLATFORM setting (useful for cross-platform installations);
  6936 more robust handling of platform specific ML images for SML/NJ;
  6937 
  6938 * the settings environment is now statically scoped, i.e. it is never
  6939 created again in sub-processes invoked from isabelle, isatool, or
  6940 Isabelle;
  6941 
  6942 * path element specification '~~' refers to '$ISABELLE_HOME';
  6943 
  6944 * in locales, the "assumes" and "defines" parts may be omitted if
  6945 empty;
  6946 
  6947 * new print_mode "xsymbols" for extended symbol support (e.g. genuine
  6948 long arrows);
  6949 
  6950 * new print_mode "HTML";
  6951 
  6952 * new flag show_tags controls display of tags of theorems (which are
  6953 basically just comments that may be attached by some tools);
  6954 
  6955 * Isamode 2.6 requires patch to accomodate change of Isabelle font
  6956 mode and goal output format:
  6957 
  6958 diff -r Isamode-2.6/elisp/isa-load.el Isamode/elisp/isa-load.el
  6959 244c244
  6960 <       (list (isa-getenv "ISABELLE") "-msymbols" logic-name)
  6961 ---
  6962 >       (list (isa-getenv "ISABELLE") "-misabelle_font" "-msymbols" logic-name)
  6963 diff -r Isabelle-2.6/elisp/isa-proofstate.el Isamode/elisp/isa-proofstate.el
  6964 181c181
  6965 < (defconst proofstate-proofstart-regexp "^Level [0-9]+$"
  6966 ---
  6967 > (defconst proofstate-proofstart-regexp "^Level [0-9]+"
  6968 
  6969 * function bind_thms stores lists of theorems (cf. bind_thm);
  6970 
  6971 * new shorthand tactics ftac, eatac, datac, fatac;
  6972 
  6973 * qed (and friends) now accept "" as result name; in that case the
  6974 theorem is not stored, but proper checks and presentation of the
  6975 result still apply;
  6976 
  6977 * theorem database now also indexes constants "Trueprop", "all",
  6978 "==>", "=="; thus thms_containing, findI etc. may retrieve more rules;
  6979 
  6980 
  6981 *** HOL ***
  6982 
  6983 ** HOL arithmetic **
  6984 
  6985 * There are now decision procedures for linear arithmetic over nat and
  6986 int:
  6987 
  6988 1. arith_tac copes with arbitrary formulae involving `=', `<', `<=',
  6989 `+', `-', `Suc', `min', `max' and numerical constants; other subterms
  6990 are treated as atomic; subformulae not involving type `nat' or `int'
  6991 are ignored; quantified subformulae are ignored unless they are
  6992 positive universal or negative existential. The tactic has to be
  6993 invoked by hand and can be a little bit slow. In particular, the
  6994 running time is exponential in the number of occurrences of `min' and
  6995 `max', and `-' on `nat'.
  6996 
  6997 2. fast_arith_tac is a cut-down version of arith_tac: it only takes
  6998 (negated) (in)equalities among the premises and the conclusion into
  6999 account (i.e. no compound formulae) and does not know about `min' and
  7000 `max', and `-' on `nat'. It is fast and is used automatically by the
  7001 simplifier.
  7002 
  7003 NB: At the moment, these decision procedures do not cope with mixed
  7004 nat/int formulae where the two parts interact, such as `m < n ==>
  7005 int(m) < int(n)'.
  7006 
  7007 * HOL/Numeral provides a generic theory of numerals (encoded
  7008 efficiently as bit strings); setup for types nat/int/real is in place;
  7009 INCOMPATIBILITY: since numeral syntax is now polymorphic, rather than
  7010 int, existing theories and proof scripts may require a few additional
  7011 type constraints;
  7012 
  7013 * integer division and remainder can now be performed on constant
  7014 arguments;
  7015 
  7016 * many properties of integer multiplication, division and remainder
  7017 are now available;
  7018 
  7019 * An interface to the Stanford Validity Checker (SVC) is available through the
  7020 tactic svc_tac.  Propositional tautologies and theorems of linear arithmetic
  7021 are proved automatically.  SVC must be installed separately, and its results
  7022 must be TAKEN ON TRUST (Isabelle does not check the proofs, but tags any
  7023 invocation of the underlying oracle).  For SVC see
  7024   http://verify.stanford.edu/SVC
  7025 
  7026 * IsaMakefile: the HOL-Real target now builds an actual image;
  7027 
  7028 
  7029 ** HOL misc **
  7030 
  7031 * HOL/Real/HahnBanach: the Hahn-Banach theorem for real vector spaces
  7032 (in Isabelle/Isar) -- by Gertrud Bauer;
  7033 
  7034 * HOL/BCV: generic model of bytecode verification, i.e. data-flow
  7035 analysis for assembly languages with subtypes;
  7036 
  7037 * HOL/TLA (Lamport's Temporal Logic of Actions): major reorganization
  7038 -- avoids syntactic ambiguities and treats state, transition, and
  7039 temporal levels more uniformly; introduces INCOMPATIBILITIES due to
  7040 changed syntax and (many) tactics;
  7041 
  7042 * HOL/inductive: Now also handles more general introduction rules such
  7043   as "ALL y. (y, x) : r --> y : acc r ==> x : acc r"; monotonicity
  7044   theorems are now maintained within the theory (maintained via the
  7045   "mono" attribute);
  7046 
  7047 * HOL/datatype: Now also handles arbitrarily branching datatypes
  7048   (using function types) such as
  7049 
  7050   datatype 'a tree = Atom 'a | Branch "nat => 'a tree"
  7051 
  7052 * HOL/record: record_simproc (part of the default simpset) takes care
  7053 of selectors applied to updated records; record_split_tac is no longer
  7054 part of the default claset; update_defs may now be removed from the
  7055 simpset in many cases; COMPATIBILITY: old behavior achieved by
  7056 
  7057   claset_ref () := claset() addSWrapper record_split_wrapper;
  7058   Delsimprocs [record_simproc]
  7059 
  7060 * HOL/typedef: fixed type inference for representing set; type
  7061 arguments now have to occur explicitly on the rhs as type constraints;
  7062 
  7063 * HOL/recdef (TFL): 'congs' syntax now expects comma separated list of theorem
  7064 names rather than an ML expression;
  7065 
  7066 * HOL/defer_recdef (TFL): like recdef but the well-founded relation can be
  7067 supplied later.  Program schemes can be defined, such as
  7068     "While B C s = (if B s then While B C (C s) else s)"
  7069 where the well-founded relation can be chosen after B and C have been given.
  7070 
  7071 * HOL/List: the constructors of type list are now Nil and Cons;
  7072 INCOMPATIBILITY: while [] and infix # syntax is still there, of
  7073 course, ML tools referring to List.list.op # etc. have to be adapted;
  7074 
  7075 * HOL_quantifiers flag superseded by "HOL" print mode, which is
  7076 disabled by default; run isabelle with option -m HOL to get back to
  7077 the original Gordon/HOL-style output;
  7078 
  7079 * HOL/Ord.thy: new bounded quantifier syntax (input only): ALL x<y. P,
  7080 ALL x<=y. P, EX x<y. P, EX x<=y. P;
  7081 
  7082 * HOL basic syntax simplified (more orthogonal): all variants of
  7083 All/Ex now support plain / symbolic / HOL notation; plain syntax for
  7084 Eps operator is provided as well: "SOME x. P[x]";
  7085 
  7086 * HOL/Sum.thy: sum_case has been moved to HOL/Datatype;
  7087 
  7088 * HOL/Univ.thy: infix syntax <*>, <+>, <**>, <+> eliminated and made
  7089 thus available for user theories;
  7090 
  7091 * HOLCF/IOA/Sequents: renamed 'Cons' to 'Consq' to avoid clash with
  7092 HOL/List; hardly an INCOMPATIBILITY since '>>' syntax is used all the
  7093 time;
  7094 
  7095 * HOL: new tactic smp_tac: int -> int -> tactic, which applies spec
  7096 several times and then mp;
  7097 
  7098 
  7099 *** LK ***
  7100 
  7101 * the notation <<...>> is now available as a notation for sequences of
  7102 formulas;
  7103 
  7104 * the simplifier is now installed
  7105 
  7106 * the axiom system has been generalized (thanks to Soren Heilmann)
  7107 
  7108 * the classical reasoner now has a default rule database
  7109 
  7110 
  7111 *** ZF ***
  7112 
  7113 * new primrec section allows primitive recursive functions to be given
  7114 directly (as in HOL) over datatypes and the natural numbers;
  7115 
  7116 * new tactics induct_tac and exhaust_tac for induction (or case
  7117 analysis) over datatypes and the natural numbers;
  7118 
  7119 * the datatype declaration of type T now defines the recursor T_rec;
  7120 
  7121 * simplification automatically does freeness reasoning for datatype
  7122 constructors;
  7123 
  7124 * automatic type-inference, with AddTCs command to insert new
  7125 type-checking rules;
  7126 
  7127 * datatype introduction rules are now added as Safe Introduction rules
  7128 to the claset;
  7129 
  7130 * the syntax "if P then x else y" is now available in addition to
  7131 if(P,x,y);
  7132 
  7133 
  7134 *** Internal programming interfaces ***
  7135 
  7136 * tuned simplifier trace output; new flag debug_simp;
  7137 
  7138 * structures Vartab / Termtab (instances of TableFun) offer efficient
  7139 tables indexed by indexname_ord / term_ord (compatible with aconv);
  7140 
  7141 * AxClass.axclass_tac lost the theory argument;
  7142 
  7143 * tuned current_goals_markers semantics: begin / end goal avoids
  7144 printing empty lines;
  7145 
  7146 * removed prs and prs_fn hook, which was broken because it did not
  7147 include \n in its semantics, forcing writeln to add one
  7148 uncoditionally; replaced prs_fn by writeln_fn; consider std_output:
  7149 string -> unit if you really want to output text without newline;
  7150 
  7151 * Symbol.output subject to print mode; INCOMPATIBILITY: defaults to
  7152 plain output, interface builders may have to enable 'isabelle_font'
  7153 mode to get Isabelle font glyphs as before;
  7154 
  7155 * refined token_translation interface; INCOMPATIBILITY: output length
  7156 now of type real instead of int;
  7157 
  7158 * theory loader actions may be traced via new ThyInfo.add_hook
  7159 interface (see src/Pure/Thy/thy_info.ML); example application: keep
  7160 your own database of information attached to *whole* theories -- as
  7161 opposed to intra-theory data slots offered via TheoryDataFun;
  7162 
  7163 * proper handling of dangling sort hypotheses (at last!);
  7164 Thm.strip_shyps and Drule.strip_shyps_warning take care of removing
  7165 extra sort hypotheses that can be witnessed from the type signature;
  7166 the force_strip_shyps flag is gone, any remaining shyps are simply
  7167 left in the theorem (with a warning issued by strip_shyps_warning);
  7168 
  7169 
  7170 
  7171 New in Isabelle98-1 (October 1998)
  7172 ----------------------------------
  7173 
  7174 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  7175 
  7176 * several changes of automated proof tools;
  7177 
  7178 * HOL: major changes to the inductive and datatype packages, including
  7179 some minor incompatibilities of theory syntax;
  7180 
  7181 * HOL: renamed r^-1 to 'converse' from 'inverse'; 'inj_onto' is now
  7182 called `inj_on';
  7183 
  7184 * HOL: removed duplicate thms in Arith:
  7185   less_imp_add_less  should be replaced by  trans_less_add1
  7186   le_imp_add_le      should be replaced by  trans_le_add1
  7187 
  7188 * HOL: unary minus is now overloaded (new type constraints may be
  7189 required);
  7190 
  7191 * HOL and ZF: unary minus for integers is now #- instead of #~.  In
  7192 ZF, expressions such as n#-1 must be changed to n#- 1, since #-1 is
  7193 now taken as an integer constant.
  7194 
  7195 * Pure: ML function 'theory_of' renamed to 'theory';
  7196 
  7197 
  7198 *** Proof tools ***
  7199 
  7200 * Simplifier:
  7201   1. Asm_full_simp_tac is now more aggressive.
  7202      1. It will sometimes reorient premises if that increases their power to
  7203         simplify.
  7204      2. It does no longer proceed strictly from left to right but may also
  7205         rotate premises to achieve further simplification.
  7206      For compatibility reasons there is now Asm_lr_simp_tac which is like the
  7207      old Asm_full_simp_tac in that it does not rotate premises.
  7208   2. The simplifier now knows a little bit about nat-arithmetic.
  7209 
  7210 * Classical reasoner: wrapper mechanism for the classical reasoner now
  7211 allows for selected deletion of wrappers, by introduction of names for
  7212 wrapper functionals.  This implies that addbefore, addSbefore,
  7213 addaltern, and addSaltern now take a pair (name, tactic) as argument,
  7214 and that adding two tactics with the same name overwrites the first
  7215 one (emitting a warning).
  7216   type wrapper = (int -> tactic) -> (int -> tactic)
  7217   setWrapper, setSWrapper, compWrapper and compSWrapper are replaced by
  7218   addWrapper, addSWrapper: claset * (string * wrapper) -> claset
  7219   delWrapper, delSWrapper: claset *  string            -> claset
  7220   getWrapper is renamed to appWrappers, getSWrapper to appSWrappers;
  7221 
  7222 * Classical reasoner: addbefore/addSbefore now have APPEND/ORELSE
  7223 semantics; addbefore now affects only the unsafe part of step_tac
  7224 etc.; this affects addss/auto_tac/force_tac, so EXISTING PROOFS MAY
  7225 FAIL, but proofs should be fixable easily, e.g. by replacing Auto_tac
  7226 by Force_tac;
  7227 
  7228 * Classical reasoner: setwrapper to setWrapper and compwrapper to
  7229 compWrapper; added safe wrapper (and access functions for it);
  7230 
  7231 * HOL/split_all_tac is now much faster and fails if there is nothing
  7232 to split.  Some EXISTING PROOFS MAY REQUIRE ADAPTION because the order
  7233 and the names of the automatically generated variables have changed.
  7234 split_all_tac has moved within claset() from unsafe wrappers to safe
  7235 wrappers, which means that !!-bound variables are split much more
  7236 aggressively, and safe_tac and clarify_tac now split such variables.
  7237 If this splitting is not appropriate, use delSWrapper "split_all_tac".
  7238 Note: the same holds for record_split_tac, which does the job of
  7239 split_all_tac for record fields.
  7240 
  7241 * HOL/Simplifier: Rewrite rules for case distinctions can now be added
  7242 permanently to the default simpset using Addsplits just like
  7243 Addsimps. They can be removed via Delsplits just like
  7244 Delsimps. Lower-case versions are also available.
  7245 
  7246 * HOL/Simplifier: The rule split_if is now part of the default
  7247 simpset. This means that the simplifier will eliminate all occurrences
  7248 of if-then-else in the conclusion of a goal. To prevent this, you can
  7249 either remove split_if completely from the default simpset by
  7250 `Delsplits [split_if]' or remove it in a specific call of the
  7251 simplifier using `... delsplits [split_if]'.  You can also add/delete
  7252 other case splitting rules to/from the default simpset: every datatype
  7253 generates suitable rules `split_t_case' and `split_t_case_asm' (where
  7254 t is the name of the datatype).
  7255 
  7256 * Classical reasoner / Simplifier combination: new force_tac (and
  7257 derivatives Force_tac, force) combines rewriting and classical
  7258 reasoning (and whatever other tools) similarly to auto_tac, but is
  7259 aimed to solve the given subgoal completely.
  7260 
  7261 
  7262 *** General ***
  7263 
  7264 * new top-level commands `Goal' and `Goalw' that improve upon `goal'
  7265 and `goalw': the theory is no longer needed as an explicit argument -
  7266 the current theory context is used; assumptions are no longer returned
  7267 at the ML-level unless one of them starts with ==> or !!; it is
  7268 recommended to convert to these new commands using isatool fixgoal
  7269 (backup your sources first!);
  7270 
  7271 * new top-level commands 'thm' and 'thms' for retrieving theorems from
  7272 the current theory context, and 'theory' to lookup stored theories;
  7273 
  7274 * new theory section 'locale' for declaring constants, assumptions and
  7275 definitions that have local scope;
  7276 
  7277 * new theory section 'nonterminals' for purely syntactic types;
  7278 
  7279 * new theory section 'setup' for generic ML setup functions
  7280 (e.g. package initialization);
  7281 
  7282 * the distribution now includes Isabelle icons: see
  7283 lib/logo/isabelle-{small,tiny}.xpm;
  7284 
  7285 * isatool install - install binaries with absolute references to
  7286 ISABELLE_HOME/bin;
  7287 
  7288 * isatool logo -- create instances of the Isabelle logo (as EPS);
  7289 
  7290 * print mode 'emacs' reserved for Isamode;
  7291 
  7292 * support multiple print (ast) translations per constant name;
  7293 
  7294 * theorems involving oracles are now printed with a suffixed [!];
  7295 
  7296 
  7297 *** HOL ***
  7298 
  7299 * there is now a tutorial on Isabelle/HOL (do 'isatool doc tutorial');
  7300 
  7301 * HOL/inductive package reorganized and improved: now supports mutual
  7302 definitions such as
  7303 
  7304   inductive EVEN ODD
  7305     intrs
  7306       null "0 : EVEN"
  7307       oddI "n : EVEN ==> Suc n : ODD"
  7308       evenI "n : ODD ==> Suc n : EVEN"
  7309 
  7310 new theorem list "elims" contains an elimination rule for each of the
  7311 recursive sets; inductive definitions now handle disjunctive premises
  7312 correctly (also ZF);
  7313 
  7314 INCOMPATIBILITIES: requires Inductive as an ancestor; component
  7315 "mutual_induct" no longer exists - the induction rule is always
  7316 contained in "induct";
  7317 
  7318 
  7319 * HOL/datatype package re-implemented and greatly improved: now
  7320 supports mutually recursive datatypes such as
  7321 
  7322   datatype
  7323     'a aexp = IF_THEN_ELSE ('a bexp) ('a aexp) ('a aexp)
  7324             | SUM ('a aexp) ('a aexp)
  7325             | DIFF ('a aexp) ('a aexp)
  7326             | NUM 'a
  7327   and
  7328     'a bexp = LESS ('a aexp) ('a aexp)
  7329             | AND ('a bexp) ('a bexp)
  7330             | OR ('a bexp) ('a bexp)
  7331 
  7332 as well as indirectly recursive datatypes such as
  7333 
  7334   datatype
  7335     ('a, 'b) term = Var 'a
  7336                   | App 'b ((('a, 'b) term) list)
  7337 
  7338 The new tactic  mutual_induct_tac [<var_1>, ..., <var_n>] i  performs
  7339 induction on mutually / indirectly recursive datatypes.
  7340 
  7341 Primrec equations are now stored in theory and can be accessed via
  7342 <function_name>.simps.
  7343 
  7344 INCOMPATIBILITIES:
  7345 
  7346   - Theories using datatypes must now have theory Datatype as an
  7347     ancestor.
  7348   - The specific <typename>.induct_tac no longer exists - use the
  7349     generic induct_tac instead.
  7350   - natE has been renamed to nat.exhaust - use exhaust_tac
  7351     instead of res_inst_tac ... natE. Note that the variable
  7352     names in nat.exhaust differ from the names in natE, this
  7353     may cause some "fragile" proofs to fail.
  7354   - The theorems split_<typename>_case and split_<typename>_case_asm
  7355     have been renamed to <typename>.split and <typename>.split_asm.
  7356   - Since default sorts of type variables are now handled correctly,
  7357     some datatype definitions may have to be annotated with explicit
  7358     sort constraints.
  7359   - Primrec definitions no longer require function name and type
  7360     of recursive argument.
  7361 
  7362 Consider using isatool fixdatatype to adapt your theories and proof
  7363 scripts to the new package (backup your sources first!).
  7364 
  7365 
  7366 * HOL/record package: considerably improved implementation; now
  7367 includes concrete syntax for record types, terms, updates; theorems
  7368 for surjective pairing and splitting !!-bound record variables; proof
  7369 support is as follows:
  7370 
  7371   1) standard conversions (selectors or updates applied to record
  7372 constructor terms) are part of the standard simpset;
  7373 
  7374   2) inject equations of the form ((x, y) = (x', y')) == x=x' & y=y' are
  7375 made part of standard simpset and claset via addIffs;
  7376 
  7377   3) a tactic for record field splitting (record_split_tac) is part of
  7378 the standard claset (addSWrapper);
  7379 
  7380 To get a better idea about these rules you may retrieve them via
  7381 something like 'thms "foo.simps"' or 'thms "foo.iffs"', where "foo" is
  7382 the name of your record type.
  7383 
  7384 The split tactic 3) conceptually simplifies by the following rule:
  7385 
  7386   "(!!x. PROP ?P x) == (!!a b. PROP ?P (a, b))"
  7387 
  7388 Thus any record variable that is bound by meta-all will automatically
  7389 blow up into some record constructor term, consequently the
  7390 simplifications of 1), 2) apply.  Thus force_tac, auto_tac etc. shall
  7391 solve record problems automatically.
  7392 
  7393 
  7394 * reorganized the main HOL image: HOL/Integ and String loaded by
  7395 default; theory Main includes everything;
  7396 
  7397 * automatic simplification of integer sums and comparisons, using cancellation;
  7398 
  7399 * added option_map_eq_Some and not_Some_eq to the default simpset and claset;
  7400 
  7401 * added disj_not1 = "(~P | Q) = (P --> Q)" to the default simpset;
  7402 
  7403 * many new identities for unions, intersections, set difference, etc.;
  7404 
  7405 * expand_if, expand_split, expand_sum_case and expand_nat_case are now
  7406 called split_if, split_split, split_sum_case and split_nat_case (to go
  7407 with add/delsplits);
  7408 
  7409 * HOL/Prod introduces simplification procedure unit_eq_proc rewriting
  7410 (?x::unit) = (); this is made part of the default simpset, which COULD
  7411 MAKE EXISTING PROOFS FAIL under rare circumstances (consider
  7412 'Delsimprocs [unit_eq_proc];' as last resort); also note that
  7413 unit_abs_eta_conv is added in order to counter the effect of
  7414 unit_eq_proc on (%u::unit. f u), replacing it by f rather than by
  7415 %u.f();
  7416 
  7417 * HOL/Fun INCOMPATIBILITY: `inj_onto' is now called `inj_on' (which
  7418 makes more sense);
  7419 
  7420 * HOL/Set INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
  7421   It and 'sym RS equals0D' are now in the default  claset, giving automatic
  7422   disjointness reasoning but breaking a few old proofs.
  7423 
  7424 * HOL/Relation INCOMPATIBILITY: renamed the relational operator r^-1
  7425 to 'converse' from 'inverse' (for compatibility with ZF and some
  7426 literature);
  7427 
  7428 * HOL/recdef can now declare non-recursive functions, with {} supplied as
  7429 the well-founded relation;
  7430 
  7431 * HOL/Set INCOMPATIBILITY: the complement of set A is now written -A instead of
  7432     Compl A.  The "Compl" syntax remains available as input syntax for this
  7433     release ONLY.
  7434 
  7435 * HOL/Update: new theory of function updates:
  7436     f(a:=b) == %x. if x=a then b else f x
  7437 may also be iterated as in f(a:=b,c:=d,...);
  7438 
  7439 * HOL/Vimage: new theory for inverse image of a function, syntax f-``B;
  7440 
  7441 * HOL/List:
  7442   - new function list_update written xs[i:=v] that updates the i-th
  7443     list position. May also be iterated as in xs[i:=a,j:=b,...].
  7444   - new function `upt' written [i..j(] which generates the list
  7445     [i,i+1,...,j-1], i.e. the upper bound is excluded. To include the upper
  7446     bound write [i..j], which is a shorthand for [i..j+1(].
  7447   - new lexicographic orderings and corresponding wellfoundedness theorems.
  7448 
  7449 * HOL/Arith:
  7450   - removed 'pred' (predecessor) function;
  7451   - generalized some theorems about n-1;
  7452   - many new laws about "div" and "mod";
  7453   - new laws about greatest common divisors (see theory ex/Primes);
  7454 
  7455 * HOL/Relation: renamed the relational operator r^-1 "converse"
  7456 instead of "inverse";
  7457 
  7458 * HOL/Induct/Multiset: a theory of multisets, including the wellfoundedness
  7459   of the multiset ordering;
  7460 
  7461 * directory HOL/Real: a construction of the reals using Dedekind cuts
  7462   (not included by default);
  7463 
  7464 * directory HOL/UNITY: Chandy and Misra's UNITY formalism;
  7465 
  7466 * directory HOL/Hoare: a new version of Hoare logic which permits many-sorted
  7467   programs, i.e. different program variables may have different types.
  7468 
  7469 * calling (stac rew i) now fails if "rew" has no effect on the goal
  7470   [previously, this check worked only if the rewrite rule was unconditional]
  7471   Now rew can involve either definitions or equalities (either == or =).
  7472 
  7473 
  7474 *** ZF ***
  7475 
  7476 * theory Main includes everything; INCOMPATIBILITY: theory ZF.thy contains
  7477   only the theorems proved on ZF.ML;
  7478 
  7479 * ZF INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
  7480   It and 'sym RS equals0D' are now in the default  claset, giving automatic
  7481   disjointness reasoning but breaking a few old proofs.
  7482 
  7483 * ZF/Update: new theory of function updates
  7484     with default rewrite rule  f(x:=y) ` z = if(z=x, y, f`z)
  7485   may also be iterated as in f(a:=b,c:=d,...);
  7486 
  7487 * in  let x=t in u(x), neither t nor u(x) has to be an FOL term.
  7488 
  7489 * calling (stac rew i) now fails if "rew" has no effect on the goal
  7490   [previously, this check worked only if the rewrite rule was unconditional]
  7491   Now rew can involve either definitions or equalities (either == or =).
  7492 
  7493 * case_tac provided for compatibility with HOL
  7494     (like the old excluded_middle_tac, but with subgoals swapped)
  7495 
  7496 
  7497 *** Internal programming interfaces ***
  7498 
  7499 * Pure: several new basic modules made available for general use, see
  7500 also src/Pure/README;
  7501 
  7502 * improved the theory data mechanism to support encapsulation (data
  7503 kind name replaced by private Object.kind, acting as authorization
  7504 key); new type-safe user interface via functor TheoryDataFun; generic
  7505 print_data function becomes basically useless;
  7506 
  7507 * removed global_names compatibility flag -- all theory declarations
  7508 are qualified by default;
  7509 
  7510 * module Pure/Syntax now offers quote / antiquote translation
  7511 functions (useful for Hoare logic etc. with implicit dependencies);
  7512 see HOL/ex/Antiquote for an example use;
  7513 
  7514 * Simplifier now offers conversions (asm_)(full_)rewrite: simpset ->
  7515 cterm -> thm;
  7516 
  7517 * new tactical CHANGED_GOAL for checking that a tactic modifies a
  7518 subgoal;
  7519 
  7520 * Display.print_goals function moved to Locale.print_goals;
  7521 
  7522 * standard print function for goals supports current_goals_markers
  7523 variable for marking begin of proof, end of proof, start of goal; the
  7524 default is ("", "", ""); setting current_goals_markers := ("<proof>",
  7525 "</proof>", "<goal>") causes SGML like tagged proof state printing,
  7526 for example;
  7527 
  7528 
  7529 
  7530 New in Isabelle98 (January 1998)
  7531 --------------------------------
  7532 
  7533 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  7534 
  7535 * changed lexical syntax of terms / types: dots made part of long
  7536 identifiers, e.g. "%x.x" no longer possible, should be "%x. x";
  7537 
  7538 * simpset (and claset) reference variable replaced by functions
  7539 simpset / simpset_ref;
  7540 
  7541 * no longer supports theory aliases (via merge) and non-trivial
  7542 implicit merge of thms' signatures;
  7543 
  7544 * most internal names of constants changed due to qualified names;
  7545 
  7546 * changed Pure/Sequence interface (see Pure/seq.ML);
  7547 
  7548 
  7549 *** General Changes ***
  7550 
  7551 * hierachically structured name spaces (for consts, types, axms, thms
  7552 etc.); new lexical class 'longid' (e.g. Foo.bar.x) may render much of
  7553 old input syntactically incorrect (e.g. "%x.x"); COMPATIBILITY:
  7554 isatool fixdots ensures space after dots (e.g. "%x. x"); set
  7555 long_names for fully qualified output names; NOTE: ML programs
  7556 (special tactics, packages etc.) referring to internal names may have
  7557 to be adapted to cope with fully qualified names; in case of severe
  7558 backward campatibility problems try setting 'global_names' at compile
  7559 time to have enrything declared within a flat name space; one may also
  7560 fine tune name declarations in theories via the 'global' and 'local'
  7561 section;
  7562 
  7563 * reimplemented the implicit simpset and claset using the new anytype
  7564 data filed in signatures; references simpset:simpset ref etc. are
  7565 replaced by functions simpset:unit->simpset and
  7566 simpset_ref:unit->simpset ref; COMPATIBILITY: use isatool fixclasimp
  7567 to patch your ML files accordingly;
  7568 
  7569 * HTML output now includes theory graph data for display with Java
  7570 applet or isatool browser; data generated automatically via isatool
  7571 usedir (see -i option, ISABELLE_USEDIR_OPTIONS);
  7572 
  7573 * defs may now be conditional; improved rewrite_goals_tac to handle
  7574 conditional equations;
  7575 
  7576 * defs now admits additional type arguments, using TYPE('a) syntax;
  7577 
  7578 * theory aliases via merge (e.g. M=A+B+C) no longer supported, always
  7579 creates a new theory node; implicit merge of thms' signatures is
  7580 restricted to 'trivial' ones; COMPATIBILITY: one may have to use
  7581 transfer:theory->thm->thm in (rare) cases;
  7582 
  7583 * improved handling of draft signatures / theories; draft thms (and
  7584 ctyps, cterms) are automatically promoted to real ones;
  7585 
  7586 * slightly changed interfaces for oracles: admit many per theory, named
  7587 (e.g. oracle foo = mlfun), additional name argument for invoke_oracle;
  7588 
  7589 * print_goals: optional output of const types (set show_consts and
  7590 show_types);
  7591 
  7592 * improved output of warnings (###) and errors (***);
  7593 
  7594 * subgoal_tac displays a warning if the new subgoal has type variables;
  7595 
  7596 * removed old README and Makefiles;
  7597 
  7598 * replaced print_goals_ref hook by print_current_goals_fn and result_error_fn;
  7599 
  7600 * removed obsolete init_pps and init_database;
  7601 
  7602 * deleted the obsolete tactical STATE, which was declared by
  7603     fun STATE tacfun st = tacfun st st;
  7604 
  7605 * cd and use now support path variables, e.g. $ISABELLE_HOME, or ~
  7606 (which abbreviates $HOME);
  7607 
  7608 * changed Pure/Sequence interface (see Pure/seq.ML); COMPATIBILITY:
  7609 use isatool fixseq to adapt your ML programs (this works for fully
  7610 qualified references to the Sequence structure only!);
  7611 
  7612 * use_thy no longer requires writable current directory; it always
  7613 reloads .ML *and* .thy file, if either one is out of date;
  7614 
  7615 
  7616 *** Classical Reasoner ***
  7617 
  7618 * Clarify_tac, clarify_tac, clarify_step_tac, Clarify_step_tac: new
  7619 tactics that use classical reasoning to simplify a subgoal without
  7620 splitting it into several subgoals;
  7621 
  7622 * Safe_tac: like safe_tac but uses the default claset;
  7623 
  7624 
  7625 *** Simplifier ***
  7626 
  7627 * added simplification meta rules:
  7628     (asm_)(full_)simplify: simpset -> thm -> thm;
  7629 
  7630 * simplifier.ML no longer part of Pure -- has to be loaded by object
  7631 logics (again);
  7632 
  7633 * added prems argument to simplification procedures;
  7634 
  7635 * HOL, FOL, ZF: added infix function `addsplits':
  7636   instead of `<simpset> setloop (split_tac <thms>)'
  7637   you can simply write `<simpset> addsplits <thms>'
  7638 
  7639 
  7640 *** Syntax ***
  7641 
  7642 * TYPE('a) syntax for type reflection terms;
  7643 
  7644 * no longer handles consts with name "" -- declare as 'syntax' instead;
  7645 
  7646 * pretty printer: changed order of mixfix annotation preference (again!);
  7647 
  7648 * Pure: fixed idt/idts vs. pttrn/pttrns syntactic categories;
  7649 
  7650 
  7651 *** HOL ***
  7652 
  7653 * HOL: there is a new splitter `split_asm_tac' that can be used e.g.
  7654   with `addloop' of the simplifier to faciliate case splitting in premises.
  7655 
  7656 * HOL/TLA: Stephan Merz's formalization of Lamport's Temporal Logic of Actions;
  7657 
  7658 * HOL/Auth: new protocol proofs including some for the Internet
  7659   protocol TLS;
  7660 
  7661 * HOL/Map: new theory of `maps' a la VDM;
  7662 
  7663 * HOL/simplifier: simplification procedures nat_cancel_sums for
  7664 cancelling out common nat summands from =, <, <= (in)equalities, or
  7665 differences; simplification procedures nat_cancel_factor for
  7666 cancelling common factor from =, <, <= (in)equalities over natural
  7667 sums; nat_cancel contains both kinds of procedures, it is installed by
  7668 default in Arith.thy -- this COULD MAKE EXISTING PROOFS FAIL;
  7669 
  7670 * HOL/simplifier: terms of the form
  7671   `? x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x)'  (or t=x)
  7672   are rewritten to
  7673   `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t)',
  7674   and those of the form
  7675   `! x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x) --> R(x)'  (or t=x)
  7676   are rewritten to
  7677   `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t) --> R(t)',
  7678 
  7679 * HOL/datatype
  7680   Each datatype `t' now comes with a theorem `split_t_case' of the form
  7681 
  7682   P(t_case f1 ... fn x) =
  7683      ( (!y1 ... ym1. x = C1 y1 ... ym1 --> P(f1 y1 ... ym1)) &
  7684         ...
  7685        (!y1 ... ymn. x = Cn y1 ... ymn --> P(f1 y1 ... ymn))
  7686      )
  7687 
  7688   and a theorem `split_t_case_asm' of the form
  7689 
  7690   P(t_case f1 ... fn x) =
  7691     ~( (? y1 ... ym1. x = C1 y1 ... ym1 & ~P(f1 y1 ... ym1)) |
  7692         ...
  7693        (? y1 ... ymn. x = Cn y1 ... ymn & ~P(f1 y1 ... ymn))
  7694      )
  7695   which can be added to a simpset via `addsplits'. The existing theorems
  7696   expand_list_case and expand_option_case have been renamed to
  7697   split_list_case and split_option_case.
  7698 
  7699 * HOL/Arithmetic:
  7700   - `pred n' is automatically converted to `n-1'.
  7701     Users are strongly encouraged not to use `pred' any longer,
  7702     because it will disappear altogether at some point.
  7703   - Users are strongly encouraged to write "0 < n" rather than
  7704     "n ~= 0". Theorems and proof tools have been modified towards this
  7705     `standard'.
  7706 
  7707 * HOL/Lists:
  7708   the function "set_of_list" has been renamed "set" (and its theorems too);
  7709   the function "nth" now takes its arguments in the reverse order and
  7710   has acquired the infix notation "!" as in "xs!n".
  7711 
  7712 * HOL/Set: UNIV is now a constant and is no longer translated to Compl{};
  7713 
  7714 * HOL/Set: The operator (UN x.B x) now abbreviates (UN x:UNIV. B x) and its
  7715   specialist theorems (like UN1_I) are gone.  Similarly for (INT x.B x);
  7716 
  7717 * HOL/record: extensible records with schematic structural subtyping
  7718 (single inheritance); EXPERIMENTAL version demonstrating the encoding,
  7719 still lacks various theorems and concrete record syntax;
  7720 
  7721 
  7722 *** HOLCF ***
  7723 
  7724 * removed "axioms" and "generated by" sections;
  7725 
  7726 * replaced "ops" section by extended "consts" section, which is capable of
  7727   handling the continuous function space "->" directly;
  7728 
  7729 * domain package:
  7730   . proves theorems immediately and stores them in the theory,
  7731   . creates hierachical name space,
  7732   . now uses normal mixfix annotations (instead of cinfix...),
  7733   . minor changes to some names and values (for consistency),
  7734   . e.g. cases -> casedist, dists_eq -> dist_eqs, [take_lemma] -> take_lemmas,
  7735   . separator between mutual domain defs: changed "," to "and",
  7736   . improved handling of sort constraints;  now they have to
  7737     appear on the left-hand side of the equations only;
  7738 
  7739 * fixed LAM <x,y,zs>.b syntax;
  7740 
  7741 * added extended adm_tac to simplifier in HOLCF -- can now discharge
  7742 adm (%x. P (t x)), where P is chainfinite and t continuous;
  7743 
  7744 
  7745 *** FOL and ZF ***
  7746 
  7747 * FOL: there is a new splitter `split_asm_tac' that can be used e.g.
  7748   with `addloop' of the simplifier to faciliate case splitting in premises.
  7749 
  7750 * qed_spec_mp, qed_goal_spec_mp, qed_goalw_spec_mp are available, as
  7751 in HOL, they strip ALL and --> from proved theorems;
  7752 
  7753 
  7754 
  7755 New in Isabelle94-8 (May 1997)
  7756 ------------------------------
  7757 
  7758 *** General Changes ***
  7759 
  7760 * new utilities to build / run / maintain Isabelle etc. (in parts
  7761 still somewhat experimental); old Makefiles etc. still functional;
  7762 
  7763 * new 'Isabelle System Manual';
  7764 
  7765 * INSTALL text, together with ./configure and ./build scripts;
  7766 
  7767 * reimplemented type inference for greater efficiency, better error
  7768 messages and clean internal interface;
  7769 
  7770 * prlim command for dealing with lots of subgoals (an easier way of
  7771 setting goals_limit);
  7772 
  7773 
  7774 *** Syntax ***
  7775 
  7776 * supports alternative (named) syntax tables (parser and pretty
  7777 printer); internal interface is provided by add_modesyntax(_i);
  7778 
  7779 * Pure, FOL, ZF, HOL, HOLCF now support symbolic input and output; to
  7780 be used in conjunction with the Isabelle symbol font; uses the
  7781 "symbols" syntax table;
  7782 
  7783 * added token_translation interface (may translate name tokens in
  7784 arbitrary ways, dependent on their type (free, bound, tfree, ...) and
  7785 the current print_mode); IMPORTANT: user print translation functions
  7786 are responsible for marking newly introduced bounds
  7787 (Syntax.mark_boundT);
  7788 
  7789 * token translations for modes "xterm" and "xterm_color" that display
  7790 names in bold, underline etc. or colors (which requires a color
  7791 version of xterm);
  7792 
  7793 * infixes may now be declared with names independent of their syntax;
  7794 
  7795 * added typed_print_translation (like print_translation, but may
  7796 access type of constant);
  7797 
  7798 
  7799 *** Classical Reasoner ***
  7800 
  7801 Blast_tac: a new tactic!  It is often more powerful than fast_tac, but has
  7802 some limitations.  Blast_tac...
  7803   + ignores addss, addbefore, addafter; this restriction is intrinsic
  7804   + ignores elimination rules that don't have the correct format
  7805         (the conclusion MUST be a formula variable)
  7806   + ignores types, which can make HOL proofs fail
  7807   + rules must not require higher-order unification, e.g. apply_type in ZF
  7808     [message "Function Var's argument not a bound variable" relates to this]
  7809   + its proof strategy is more general but can actually be slower
  7810 
  7811 * substitution with equality assumptions no longer permutes other
  7812 assumptions;
  7813 
  7814 * minor changes in semantics of addafter (now called addaltern); renamed
  7815 setwrapper to setWrapper and compwrapper to compWrapper; added safe wrapper
  7816 (and access functions for it);
  7817 
  7818 * improved combination of classical reasoner and simplifier:
  7819   + functions for handling clasimpsets
  7820   + improvement of addss: now the simplifier is called _after_ the
  7821     safe steps.
  7822   + safe variant of addss called addSss: uses safe simplifications
  7823     _during_ the safe steps. It is more complete as it allows multiple
  7824     instantiations of unknowns (e.g. with slow_tac).
  7825 
  7826 *** Simplifier ***
  7827 
  7828 * added interface for simplification procedures (functions that
  7829 produce *proven* rewrite rules on the fly, depending on current
  7830 redex);
  7831 
  7832 * ordering on terms as parameter (used for ordered rewriting);
  7833 
  7834 * new functions delcongs, deleqcongs, and Delcongs. richer rep_ss;
  7835 
  7836 * the solver is now split into a safe and an unsafe part.
  7837 This should be invisible for the normal user, except that the
  7838 functions setsolver and addsolver have been renamed to setSolver and
  7839 addSolver; added safe_asm_full_simp_tac;
  7840 
  7841 
  7842 *** HOL ***
  7843 
  7844 * a generic induction tactic `induct_tac' which works for all datatypes and
  7845 also for type `nat';
  7846 
  7847 * a generic case distinction tactic `exhaust_tac' which works for all
  7848 datatypes and also for type `nat';
  7849 
  7850 * each datatype comes with a function `size';
  7851 
  7852 * patterns in case expressions allow tuple patterns as arguments to
  7853 constructors, for example `case x of [] => ... | (x,y,z)#ps => ...';
  7854 
  7855 * primrec now also works with type nat;
  7856 
  7857 * recdef: a new declaration form, allows general recursive functions to be
  7858 defined in theory files.  See HOL/ex/Fib, HOL/ex/Primes, HOL/Subst/Unify.
  7859 
  7860 * the constant for negation has been renamed from "not" to "Not" to
  7861 harmonize with FOL, ZF, LK, etc.;
  7862 
  7863 * HOL/ex/LFilter theory of a corecursive "filter" functional for
  7864 infinite lists;
  7865 
  7866 * HOL/Modelcheck demonstrates invocation of model checker oracle;
  7867 
  7868 * HOL/ex/Ring.thy declares cring_simp, which solves equational
  7869 problems in commutative rings, using axiomatic type classes for + and *;
  7870 
  7871 * more examples in HOL/MiniML and HOL/Auth;
  7872 
  7873 * more default rewrite rules for quantifiers, union/intersection;
  7874 
  7875 * a new constant `arbitrary == @x.False';
  7876 
  7877 * HOLCF/IOA replaces old HOL/IOA;
  7878 
  7879 * HOLCF changes: derived all rules and arities
  7880   + axiomatic type classes instead of classes
  7881   + typedef instead of faking type definitions
  7882   + eliminated the internal constants less_fun, less_cfun, UU_fun, UU_cfun etc.
  7883   + new axclasses cpo, chfin, flat with flat < chfin < pcpo < cpo < po
  7884   + eliminated the types void, one, tr
  7885   + use unit lift and bool lift (with translations) instead of one and tr
  7886   + eliminated blift from Lift3.thy (use Def instead of blift)
  7887   all eliminated rules are derived as theorems --> no visible changes ;
  7888 
  7889 
  7890 *** ZF ***
  7891 
  7892 * ZF now has Fast_tac, Simp_tac and Auto_tac.  Union_iff is a now a default
  7893 rewrite rule; this may affect some proofs.  eq_cs is gone but can be put back
  7894 as ZF_cs addSIs [equalityI];
  7895 
  7896 
  7897 
  7898 New in Isabelle94-7 (November 96)
  7899 ---------------------------------
  7900 
  7901 * allowing negative levels (as offsets) in prlev and choplev;
  7902 
  7903 * super-linear speedup for large simplifications;
  7904 
  7905 * FOL, ZF and HOL now use miniscoping: rewriting pushes
  7906 quantifications in as far as possible (COULD MAKE EXISTING PROOFS
  7907 FAIL); can suppress it using the command Delsimps (ex_simps @
  7908 all_simps); De Morgan laws are also now included, by default;
  7909 
  7910 * improved printing of ==>  :  ~:
  7911 
  7912 * new object-logic "Sequents" adds linear logic, while replacing LK
  7913 and Modal (thanks to Sara Kalvala);
  7914 
  7915 * HOL/Auth: correctness proofs for authentication protocols;
  7916 
  7917 * HOL: new auto_tac combines rewriting and classical reasoning (many
  7918 examples on HOL/Auth);
  7919 
  7920 * HOL: new command AddIffs for declaring theorems of the form P=Q to
  7921 the rewriter and classical reasoner simultaneously;
  7922 
  7923 * function uresult no longer returns theorems in "standard" format;
  7924 regain previous version by: val uresult = standard o uresult;
  7925 
  7926 
  7927 
  7928 New in Isabelle94-6
  7929 -------------------
  7930 
  7931 * oracles -- these establish an interface between Isabelle and trusted
  7932 external reasoners, which may deliver results as theorems;
  7933 
  7934 * proof objects (in particular record all uses of oracles);
  7935 
  7936 * Simp_tac, Fast_tac, etc. that refer to implicit simpset / claset;
  7937 
  7938 * "constdefs" section in theory files;
  7939 
  7940 * "primrec" section (HOL) no longer requires names;
  7941 
  7942 * internal type "tactic" now simply "thm -> thm Sequence.seq";
  7943 
  7944 
  7945 
  7946 New in Isabelle94-5
  7947 -------------------
  7948 
  7949 * reduced space requirements;
  7950 
  7951 * automatic HTML generation from theories;
  7952 
  7953 * theory files no longer require "..." (quotes) around most types;
  7954 
  7955 * new examples, including two proofs of the Church-Rosser theorem;
  7956 
  7957 * non-curried (1994) version of HOL is no longer distributed;
  7958 
  7959 
  7960 
  7961 New in Isabelle94-4
  7962 -------------------
  7963 
  7964 * greatly reduced space requirements;
  7965 
  7966 * theory files (.thy) no longer require \...\ escapes at line breaks;
  7967 
  7968 * searchable theorem database (see the section "Retrieving theorems" on
  7969 page 8 of the Reference Manual);
  7970 
  7971 * new examples, including Grabczewski's monumental case study of the
  7972 Axiom of Choice;
  7973 
  7974 * The previous version of HOL renamed to Old_HOL;
  7975 
  7976 * The new version of HOL (previously called CHOL) uses a curried syntax
  7977 for functions.  Application looks like f a b instead of f(a,b);
  7978 
  7979 * Mutually recursive inductive definitions finally work in HOL;
  7980 
  7981 * In ZF, pattern-matching on tuples is now available in all abstractions and
  7982 translates to the operator "split";
  7983 
  7984 
  7985 
  7986 New in Isabelle94-3
  7987 -------------------
  7988 
  7989 * new infix operator, addss, allowing the classical reasoner to
  7990 perform simplification at each step of its search.  Example:
  7991         fast_tac (cs addss ss)
  7992 
  7993 * a new logic, CHOL, the same as HOL, but with a curried syntax
  7994 for functions.  Application looks like f a b instead of f(a,b).  Also pairs
  7995 look like (a,b) instead of <a,b>;
  7996 
  7997 * PLEASE NOTE: CHOL will eventually replace HOL!
  7998 
  7999 * In CHOL, pattern-matching on tuples is now available in all abstractions.
  8000 It translates to the operator "split".  A new theory of integers is available;
  8001 
  8002 * In ZF, integer numerals now denote two's-complement binary integers.
  8003 Arithmetic operations can be performed by rewriting.  See ZF/ex/Bin.ML;
  8004 
  8005 * Many new examples: I/O automata, Church-Rosser theorem, equivalents
  8006 of the Axiom of Choice;
  8007 
  8008 
  8009 
  8010 New in Isabelle94-2
  8011 -------------------
  8012 
  8013 * Significantly faster resolution;
  8014 
  8015 * the different sections in a .thy file can now be mixed and repeated
  8016 freely;
  8017 
  8018 * Database of theorems for FOL, HOL and ZF.  New
  8019 commands including qed, qed_goal and bind_thm store theorems in the database.
  8020 
  8021 * Simple database queries: return a named theorem (get_thm) or all theorems of
  8022 a given theory (thms_of), or find out what theory a theorem was proved in
  8023 (theory_of_thm);
  8024 
  8025 * Bugs fixed in the inductive definition and datatype packages;
  8026 
  8027 * The classical reasoner provides deepen_tac and depth_tac, making FOL_dup_cs
  8028 and HOL_dup_cs obsolete;
  8029 
  8030 * Syntactic ambiguities caused by the new treatment of syntax in Isabelle94-1
  8031 have been removed;
  8032 
  8033 * Simpler definition of function space in ZF;
  8034 
  8035 * new results about cardinal and ordinal arithmetic in ZF;
  8036 
  8037 * 'subtype' facility in HOL for introducing new types as subsets of existing
  8038 types;
  8039 
  8040 :mode=text:wrap=hard:maxLineLen=72: