NEWS
author wenzelm
Fri, 08 Apr 2011 13:31:16 +0200
changeset 43156 326f57825e1a
parent 43122 12fe41a92cd5
child 43162 b1f544c84040
permissions -rw-r--r--
explicit structure Syntax_Trans;
discontinued old-style constrainAbsC;
     1 Isabelle NEWS -- history user-relevant changes
     2 ==============================================
     3 
     4 New in this Isabelle version
     5 ----------------------------
     6 
     7 *** General ***
     8 
     9 * Theory loader: source files are identified by content via SHA1
    10 digests.  Discontinued former path/modtime identification and optional
    11 ISABELLE_FILE_IDENT plugin scripts.
    12 
    13 * Parallelization of nested Isar proofs is subject to
    14 Goal.parallel_proofs_threshold (default 100).  See also isabelle
    15 usedir option -Q.
    16 
    17 * Discontinued support for Poly/ML 5.2, which was the last version
    18 without proper multithreading and TimeLimit implementation.
    19 
    20 * Discontinued old lib/scripts/polyml-platform, which has been
    21 obsolete since Isabelle2009-2.
    22 
    23 * Theory loader: source files are exclusively located via the master
    24 directory of each theory node (where the .thy file itself resides).
    25 The global load path (such as src/HOL/Library) is has been
    26 discontinued.  INCOMPATIBILITY.
    27 
    28 * Various optional external tools are referenced more robustly and
    29 uniformly by explicit Isabelle settings as follows:
    30 
    31   ISABELLE_CSDP   (formerly CSDP_EXE)
    32   ISABELLE_GHC    (formerly EXEC_GHC or GHC_PATH)
    33   ISABELLE_OCAML  (formerly EXEC_OCAML)
    34   ISABELLE_SWIPL  (formerly EXEC_SWIPL)
    35   ISABELLE_YAP    (formerly EXEC_YAP)
    36 
    37 Note that automated detection from the file-system or search path has
    38 been discontinued.  INCOMPATIBILITY.
    39 
    40 
    41 *** HOL ***
    42 
    43 * Nitpick:
    44   - Added "need" and "total_consts" options.
    45   - Reintroduced "show_skolems" option by popular demand.
    46   - Renamed attribute: nitpick_def ~> nitpick_unfold.
    47     INCOMPATIBILITY.
    48 
    49 * Sledgehammer:
    50   - sledgehammer available_provers ~> sledgehammer supported_provers
    51     INCOMPATIBILITY.
    52   - Added "monomorphize", "monomorphize_limit", and "type_sys" options.
    53 
    54 * "try":
    55   - Added "simp:", "intro:", and "elim:" options.
    56 
    57 * Quickcheck:
    58   - Added "eval" option to evaluate terms for the found counterexample
    59     (currently only supported by the default (exhaustive) tester)
    60   - Added post-processing of terms to obtain readable counterexamples
    61     (currently only supported by the default (exhaustive) tester)
    62 
    63 * Function package: discontinued option "tailrec".
    64 INCOMPATIBILITY. Use partial_function instead.
    65 
    66 * HOL-Probability:
    67   - Caratheodory's extension lemma is now proved for ring_of_sets.
    68   - Infinite products of probability measures are now available.
    69   - Use extended reals instead of positive extended reals.
    70     INCOMPATIBILITY.
    71 
    72 *** Document preparation ***
    73 
    74 * New term style "isub" as ad-hoc conversion of variables x1, y23 into
    75 subscripted form x\<^isub>1, y\<^isub>2\<^isub>3.
    76 
    77 
    78 *** ML ***
    79 
    80 * Structure Timing provides various operations for timing; supersedes
    81 former start_timing/end_timing etc.
    82 
    83 * Path.print is the official way to show file-system paths to users
    84 (including quotes etc.).
    85 
    86 * Inner syntax: identifiers in parse trees of generic categories
    87 "logic", "aprop", "idt" etc. carry position information (disguised as
    88 type constraints).  Occasional INCOMPATIBILITY with non-compliant
    89 translations that choke on unexpected type constraints.  Positions can
    90 be stripped in ML translations via Syntax.strip_positions /
    91 Syntax.strip_positions_ast, or via the syntax constant
    92 "_strip_positions" within parse trees.  As last resort, positions can
    93 be disabled via the configuration option Syntax.positions, which is
    94 called "syntax_positions" in Isar attribute syntax.
    95 
    96 * Discontinued special treatment of various ML structures of inner
    97 syntax, such as structure Ast: no pervasive content, no inclusion in
    98 structure Syntax.  INCOMPATIBILITY, refer to qualified names like
    99 Ast.Constant etc.
   100 
   101 * Typed print translation: discontinued show_sorts argument, which is
   102 already available via context of "advanced" translation.
   103 
   104 
   105 
   106 New in Isabelle2011 (January 2011)
   107 ----------------------------------
   108 
   109 *** General ***
   110 
   111 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
   112 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
   113 useful tooltips and hyperlinks produced from its static analysis.  The
   114 bundled component provides an executable Isabelle tool that can be run
   115 like this:
   116 
   117   Isabelle2011/bin/isabelle jedit
   118 
   119 * Significantly improved Isabelle/Isar implementation manual.
   120 
   121 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
   122 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
   123 while the default heap location within that directory lacks that extra
   124 suffix.  This isolates multiple Isabelle installations from each
   125 other, avoiding problems with old settings in new versions.
   126 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
   127 
   128 * Source files are always encoded as UTF-8, instead of old-fashioned
   129 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
   130 the following package declarations:
   131 
   132   \usepackage[utf8]{inputenc}
   133   \usepackage{textcomp}
   134 
   135 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
   136 a Unicode character is treated as a single symbol, not a sequence of
   137 non-ASCII bytes as before.  Since Isabelle/ML string literals may
   138 contain symbols without further backslash escapes, Unicode can now be
   139 used here as well.  Recall that Symbol.explode in ML provides a
   140 consistent view on symbols, while raw explode (or String.explode)
   141 merely give a byte-oriented representation.
   142 
   143 * Theory loader: source files are primarily located via the master
   144 directory of each theory node (where the .thy file itself resides).
   145 The global load path is still partially available as legacy feature.
   146 Minor INCOMPATIBILITY due to subtle change in file lookup: use
   147 explicit paths, relatively to the theory.
   148 
   149 * Special treatment of ML file names has been discontinued.
   150 Historically, optional extensions .ML or .sml were added on demand --
   151 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
   152 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
   153 
   154 * Various options that affect pretty printing etc. are now properly
   155 handled within the context via configuration options, instead of
   156 unsynchronized references or print modes.  There are both ML Config.T
   157 entities and Isar declaration attributes to access these.
   158 
   159   ML (Config.T)                 Isar (attribute)
   160 
   161   eta_contract                  eta_contract
   162   show_brackets                 show_brackets
   163   show_sorts                    show_sorts
   164   show_types                    show_types
   165   show_question_marks           show_question_marks
   166   show_consts                   show_consts
   167   show_abbrevs                  show_abbrevs
   168 
   169   Syntax.ast_trace              syntax_ast_trace
   170   Syntax.ast_stat               syntax_ast_stat
   171   Syntax.ambiguity_level        syntax_ambiguity_level
   172 
   173   Goal_Display.goals_limit      goals_limit
   174   Goal_Display.show_main_goal   show_main_goal
   175 
   176   Method.rule_trace             rule_trace
   177 
   178   Thy_Output.display            thy_output_display
   179   Thy_Output.quotes             thy_output_quotes
   180   Thy_Output.indent             thy_output_indent
   181   Thy_Output.source             thy_output_source
   182   Thy_Output.break              thy_output_break
   183 
   184 Note that corresponding "..._default" references in ML may only be
   185 changed globally at the ROOT session setup, but *not* within a theory.
   186 The option "show_abbrevs" supersedes the former print mode
   187 "no_abbrevs" with inverted meaning.
   188 
   189 * More systematic naming of some configuration options.
   190 INCOMPATIBILITY.
   191 
   192   trace_simp  ~>  simp_trace
   193   debug_simp  ~>  simp_debug
   194 
   195 * Support for real valued configuration options, using simplistic
   196 floating-point notation that coincides with the inner syntax for
   197 float_token.
   198 
   199 * Support for real valued preferences (with approximative PGIP type):
   200 front-ends need to accept "pgint" values in float notation.
   201 INCOMPATIBILITY.
   202 
   203 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
   204 DejaVu Sans.
   205 
   206 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   207 
   208 
   209 *** Pure ***
   210 
   211 * Command 'type_synonym' (with single argument) replaces somewhat
   212 outdated 'types', which is still available as legacy feature for some
   213 time.
   214 
   215 * Command 'nonterminal' (with 'and' separated list of arguments)
   216 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
   217 
   218 * Command 'notepad' replaces former 'example_proof' for
   219 experimentation in Isar without any result.  INCOMPATIBILITY.
   220 
   221 * Locale interpretation commands 'interpret' and 'sublocale' accept
   222 lists of equations to map definitions in a locale to appropriate
   223 entities in the context of the interpretation.  The 'interpretation'
   224 command already provided this functionality.
   225 
   226 * Diagnostic command 'print_dependencies' prints the locale instances
   227 that would be activated if the specified expression was interpreted in
   228 the current context.  Variant "print_dependencies!" assumes a context
   229 without interpretations.
   230 
   231 * Diagnostic command 'print_interps' prints interpretations in proofs
   232 in addition to interpretations in theories.
   233 
   234 * Discontinued obsolete 'global' and 'local' commands to manipulate
   235 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
   236 Sign.root_path and Sign.local_path may be applied directly where this
   237 feature is still required for historical reasons.
   238 
   239 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
   240 'definition' instead.
   241 
   242 * The "prems" fact, which refers to the accidental collection of
   243 foundational premises in the context, is now explicitly marked as
   244 legacy feature and will be discontinued soon.  Consider using "assms"
   245 of the head statement or reference facts by explicit names.
   246 
   247 * Document antiquotations @{class} and @{type} print classes and type
   248 constructors.
   249 
   250 * Document antiquotation @{file} checks file/directory entries within
   251 the local file system.
   252 
   253 
   254 *** HOL ***
   255 
   256 * Coercive subtyping: functions can be declared as coercions and type
   257 inference will add them as necessary upon input of a term.  Theory
   258 Complex_Main declares real :: nat => real and real :: int => real as
   259 coercions. A coercion function f is declared like this:
   260 
   261   declare [[coercion f]]
   262 
   263 To lift coercions through type constructors (e.g. from nat => real to
   264 nat list => real list), map functions can be declared, e.g.
   265 
   266   declare [[coercion_map map]]
   267 
   268 Currently coercion inference is activated only in theories including
   269 real numbers, i.e. descendants of Complex_Main.  This is controlled by
   270 the configuration option "coercion_enabled", e.g. it can be enabled in
   271 other theories like this:
   272 
   273   declare [[coercion_enabled]]
   274 
   275 * Command 'partial_function' provides basic support for recursive
   276 function definitions over complete partial orders.  Concrete instances
   277 are provided for i) the option type, ii) tail recursion on arbitrary
   278 types, and iii) the heap monad of Imperative_HOL.  See
   279 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
   280 for examples.
   281 
   282 * Function package: f.psimps rules are no longer implicitly declared
   283 as [simp].  INCOMPATIBILITY.
   284 
   285 * Datatype package: theorems generated for executable equality (class
   286 "eq") carry proper names and are treated as default code equations.
   287 
   288 * Inductive package: now offers command 'inductive_simps' to
   289 automatically derive instantiated and simplified equations for
   290 inductive predicates, similar to 'inductive_cases'.
   291 
   292 * Command 'enriched_type' allows to register properties of the
   293 functorial structure of types.
   294 
   295 * Improved infrastructure for term evaluation using code generator
   296 techniques, in particular static evaluation conversions.
   297 
   298 * Code generator: Scala (2.8 or higher) has been added to the target
   299 languages.
   300 
   301 * Code generator: globbing constant expressions "*" and "Theory.*"
   302 have been replaced by the more idiomatic "_" and "Theory._".
   303 INCOMPATIBILITY.
   304 
   305 * Code generator: export_code without explicit file declaration prints
   306 to standard output.  INCOMPATIBILITY.
   307 
   308 * Code generator: do not print function definitions for case
   309 combinators any longer.
   310 
   311 * Code generator: simplification with rules determined with
   312 src/Tools/Code/code_simp.ML and method "code_simp".
   313 
   314 * Code generator for records: more idiomatic representation of record
   315 types.  Warning: records are not covered by ancient SML code
   316 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
   317 rep_datatype declaration helps to succeed then:
   318 
   319   record 'a foo = ...
   320   ...
   321   rep_datatype foo_ext ...
   322 
   323 * Records: logical foundation type for records does not carry a
   324 '_type' suffix any longer (obsolete due to authentic syntax).
   325 INCOMPATIBILITY.
   326 
   327 * Quickcheck now by default uses exhaustive testing instead of random
   328 testing.  Random testing can be invoked by "quickcheck [random]",
   329 exhaustive testing by "quickcheck [exhaustive]".
   330 
   331 * Quickcheck instantiates polymorphic types with small finite
   332 datatypes by default. This enables a simple execution mechanism to
   333 handle quantifiers and function equality over the finite datatypes.
   334 
   335 * Quickcheck random generator has been renamed from "code" to
   336 "random".  INCOMPATIBILITY.
   337 
   338 * Quickcheck now has a configurable time limit which is set to 30
   339 seconds by default. This can be changed by adding [timeout = n] to the
   340 quickcheck command. The time limit for Auto Quickcheck is still set
   341 independently.
   342 
   343 * Quickcheck in locales considers interpretations of that locale for
   344 counter example search.
   345 
   346 * Sledgehammer:
   347   - Added "smt" and "remote_smt" provers based on the "smt" proof
   348     method. See the Sledgehammer manual for details ("isabelle doc
   349     sledgehammer").
   350   - Renamed commands:
   351     sledgehammer atp_info ~> sledgehammer running_provers
   352     sledgehammer atp_kill ~> sledgehammer kill_provers
   353     sledgehammer available_atps ~> sledgehammer available_provers
   354     INCOMPATIBILITY.
   355   - Renamed options:
   356     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
   357     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
   358     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
   359     (and "ms" and "min" are no longer supported)
   360     INCOMPATIBILITY.
   361 
   362 * Nitpick:
   363   - Renamed options:
   364     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
   365     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
   366     INCOMPATIBILITY.
   367   - Added support for partial quotient types.
   368   - Added local versions of the "Nitpick.register_xxx" functions.
   369   - Added "whack" option.
   370   - Allow registration of quotient types as codatatypes.
   371   - Improved "merge_type_vars" option to merge more types.
   372   - Removed unsound "fast_descrs" option.
   373   - Added custom symmetry breaking for datatypes, making it possible to reach
   374     higher cardinalities.
   375   - Prevent the expansion of too large definitions.
   376 
   377 * Proof methods "metis" and "meson" now have configuration options
   378 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
   379 to diagnose these tools. E.g.
   380 
   381     using [[metis_trace = true]]
   382 
   383 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
   384 manually as command 'solve_direct'.
   385 
   386 * The default SMT solver Z3 must be enabled explicitly (due to
   387 licensing issues) by setting the environment variable
   388 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
   389 commercial applications, the SMT solver CVC3 is provided as fall-back;
   390 changing the SMT solver is done via the configuration option
   391 "smt_solver".
   392 
   393 * Remote SMT solvers need to be referred to by the "remote_" prefix,
   394 i.e. "remote_cvc3" and "remote_z3".
   395 
   396 * Added basic SMT support for datatypes, records, and typedefs using
   397 the oracle mode (no proofs).  Direct support of pairs has been dropped
   398 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
   399 support for a similar behavior).  Minor INCOMPATIBILITY.
   400 
   401 * Changed SMT configuration options:
   402   - Renamed:
   403     z3_proofs ~> smt_oracle (with inverted meaning)
   404     z3_trace_assms ~> smt_trace_used_facts
   405     INCOMPATIBILITY.
   406   - Added:
   407     smt_verbose
   408     smt_random_seed
   409     smt_datatypes
   410     smt_infer_triggers
   411     smt_monomorph_limit
   412     cvc3_options
   413     remote_cvc3_options
   414     remote_z3_options
   415     yices_options
   416 
   417 * Boogie output files (.b2i files) need to be declared in the theory
   418 header.
   419 
   420 * Simplification procedure "list_to_set_comprehension" rewrites list
   421 comprehensions applied to List.set to set comprehensions.  Occasional
   422 INCOMPATIBILITY, may be deactivated like this:
   423 
   424   declare [[simproc del: list_to_set_comprehension]]
   425 
   426 * Removed old version of primrec package.  INCOMPATIBILITY.
   427 
   428 * Removed simplifier congruence rule of "prod_case", as has for long
   429 been the case with "split".  INCOMPATIBILITY.
   430 
   431 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
   432 
   433 * Removed [split_format ... and ... and ...] version of
   434 [split_format].  Potential INCOMPATIBILITY.
   435 
   436 * Predicate "sorted" now defined inductively, with nice induction
   437 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
   438 
   439 * Constant "contents" renamed to "the_elem", to free the generic name
   440 contents for other uses.  INCOMPATIBILITY.
   441 
   442 * Renamed class eq and constant eq (for code generation) to class
   443 equal and constant equal, plus renaming of related facts and various
   444 tuning.  INCOMPATIBILITY.
   445 
   446 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
   447 
   448 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
   449 INCOMPATIBILITY.
   450 
   451 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
   452 avoid confusion with finite sets.  INCOMPATIBILITY.
   453 
   454 * Abandoned locales equiv, congruent and congruent2 for equivalence
   455 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
   456 for congruent(2)).
   457 
   458 * Some previously unqualified names have been qualified:
   459 
   460   types
   461     bool ~> HOL.bool
   462     nat ~> Nat.nat
   463 
   464   constants
   465     Trueprop ~> HOL.Trueprop
   466     True ~> HOL.True
   467     False ~> HOL.False
   468     op & ~> HOL.conj
   469     op | ~> HOL.disj
   470     op --> ~> HOL.implies
   471     op = ~> HOL.eq
   472     Not ~> HOL.Not
   473     The ~> HOL.The
   474     All ~> HOL.All
   475     Ex ~> HOL.Ex
   476     Ex1 ~> HOL.Ex1
   477     Let ~> HOL.Let
   478     If ~> HOL.If
   479     Ball ~> Set.Ball
   480     Bex ~> Set.Bex
   481     Suc ~> Nat.Suc
   482     Pair ~> Product_Type.Pair
   483     fst ~> Product_Type.fst
   484     snd ~> Product_Type.snd
   485     curry ~> Product_Type.curry
   486     op : ~> Set.member
   487     Collect ~> Set.Collect
   488 
   489 INCOMPATIBILITY.
   490 
   491 * More canonical naming convention for some fundamental definitions:
   492 
   493     bot_bool_eq ~> bot_bool_def
   494     top_bool_eq ~> top_bool_def
   495     inf_bool_eq ~> inf_bool_def
   496     sup_bool_eq ~> sup_bool_def
   497     bot_fun_eq  ~> bot_fun_def
   498     top_fun_eq  ~> top_fun_def
   499     inf_fun_eq  ~> inf_fun_def
   500     sup_fun_eq  ~> sup_fun_def
   501 
   502 INCOMPATIBILITY.
   503 
   504 * More stylized fact names:
   505 
   506   expand_fun_eq ~> fun_eq_iff
   507   expand_set_eq ~> set_eq_iff
   508   set_ext       ~> set_eqI
   509   nat_number    ~> eval_nat_numeral
   510 
   511 INCOMPATIBILITY.
   512 
   513 * Refactoring of code-generation specific operations in theory List:
   514 
   515   constants
   516     null ~> List.null
   517 
   518   facts
   519     mem_iff ~> member_def
   520     null_empty ~> null_def
   521 
   522 INCOMPATIBILITY.  Note that these were not supposed to be used
   523 regularly unless for striking reasons; their main purpose was code
   524 generation.
   525 
   526 Various operations from the Haskell prelude are used for generating
   527 Haskell code.
   528 
   529 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
   530 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
   531 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
   532 
   533 * Abolished some non-alphabetic type names: "prod" and "sum" replace
   534 "*" and "+" respectively.  INCOMPATIBILITY.
   535 
   536 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
   537 "Sum_Type.Plus" instead.
   538 
   539 * Constant "split" has been merged with constant "prod_case"; names of
   540 ML functions, facts etc. involving split have been retained so far,
   541 though.  INCOMPATIBILITY.
   542 
   543 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
   544 instead.  INCOMPATIBILITY.
   545 
   546 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
   547 INCOMPATIBILITY.
   548 
   549 * Former theory Library/Enum is now part of the HOL-Main image.
   550 INCOMPATIBILITY: all constants of the Enum theory now have to be
   551 referred to by its qualified name.
   552 
   553   enum    ~>  Enum.enum
   554   nlists  ~>  Enum.nlists
   555   product ~>  Enum.product
   556 
   557 * Theory Library/Monad_Syntax provides do-syntax for monad types.
   558 Syntax in Library/State_Monad has been changed to avoid ambiguities.
   559 INCOMPATIBILITY.
   560 
   561 * Theory Library/SetsAndFunctions has been split into
   562 Library/Function_Algebras and Library/Set_Algebras; canonical names
   563 for instance definitions for functions; various improvements.
   564 INCOMPATIBILITY.
   565 
   566 * Theory Library/Multiset provides stable quicksort implementation of
   567 sort_key.
   568 
   569 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
   570 INCOMPATIBILITY.
   571 
   572 * Session Multivariate_Analysis: introduced a type class for euclidean
   573 space.  Most theorems are now stated in terms of euclidean spaces
   574 instead of finite cartesian products.
   575 
   576   types
   577     real ^ 'n ~>  'a::real_vector
   578               ~>  'a::euclidean_space
   579               ~>  'a::ordered_euclidean_space
   580         (depends on your needs)
   581 
   582   constants
   583      _ $ _        ~> _ $$ _
   584      \<chi> x. _  ~> \<chi>\<chi> x. _
   585      CARD('n)     ~> DIM('a)
   586 
   587 Also note that the indices are now natural numbers and not from some
   588 finite type. Finite cartesian products of euclidean spaces, products
   589 of euclidean spaces the real and complex numbers are instantiated to
   590 be euclidean_spaces.  INCOMPATIBILITY.
   591 
   592 * Session Probability: introduced pextreal as positive extended real
   593 numbers.  Use pextreal as value for measures.  Introduce the
   594 Radon-Nikodym derivative, product spaces and Fubini's theorem for
   595 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
   596 the integral in Multivariate Analysis.  INCOMPATIBILITY.
   597 
   598 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   599 INCOMPATIBILITY.
   600 
   601 * Session SPARK (with image HOL-SPARK) provides commands to load and
   602 prove verification conditions generated by the SPARK Ada program
   603 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
   604 
   605 
   606 *** HOL-Algebra ***
   607 
   608 * Theorems for additive ring operations (locale abelian_monoid and
   609 descendants) are generated by interpretation from their multiplicative
   610 counterparts.  Names (in particular theorem names) have the mandatory
   611 qualifier 'add'.  Previous theorem names are redeclared for
   612 compatibility.
   613 
   614 * Structure "int_ring" is now an abbreviation (previously a
   615 definition).  This fits more natural with advanced interpretations.
   616 
   617 
   618 *** HOLCF ***
   619 
   620 * The domain package now runs in definitional mode by default: The
   621 former command 'new_domain' is now called 'domain'.  To use the domain
   622 package in its original axiomatic mode, use 'domain (unsafe)'.
   623 INCOMPATIBILITY.
   624 
   625 * The new class "domain" is now the default sort.  Class "predomain"
   626 is an unpointed version of "domain". Theories can be updated by
   627 replacing sort annotations as shown below.  INCOMPATIBILITY.
   628 
   629   'a::type ~> 'a::countable
   630   'a::cpo  ~> 'a::predomain
   631   'a::pcpo ~> 'a::domain
   632 
   633 * The old type class "rep" has been superseded by class "domain".
   634 Accordingly, users of the definitional package must remove any
   635 "default_sort rep" declarations.  INCOMPATIBILITY.
   636 
   637 * The domain package (definitional mode) now supports unpointed
   638 predomain argument types, as long as they are marked 'lazy'. (Strict
   639 arguments must be in class "domain".) For example, the following
   640 domain definition now works:
   641 
   642   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
   643 
   644 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
   645 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
   646 'a option, and 'a list.  Additionally, it configures fixrec and the
   647 domain package to work with these types.  For example:
   648 
   649   fixrec isInl :: "('a + 'b) u -> tr"
   650     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
   651 
   652   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
   653 
   654 * The "(permissive)" option of fixrec has been replaced with a
   655 per-equation "(unchecked)" option. See
   656 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
   657 
   658 * The "bifinite" class no longer fixes a constant "approx"; the class
   659 now just asserts that such a function exists.  INCOMPATIBILITY.
   660 
   661 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
   662 defines an embedding of type 'a defl into udom by default; instances
   663 of "bifinite" and "domain" classes are available in
   664 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
   665 
   666 * The syntax "REP('a)" has been replaced with "DEFL('a)".
   667 
   668 * The predicate "directed" has been removed.  INCOMPATIBILITY.
   669 
   670 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
   671 
   672 * The function "cprod_map" has been renamed to "prod_map".
   673 INCOMPATIBILITY.
   674 
   675 * The monadic bind operator on each powerdomain has new binder syntax
   676 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
   677 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
   678 
   679 * The infix syntax for binary union on each powerdomain has changed
   680 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
   681 syntax.  INCOMPATIBILITY.
   682 
   683 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
   684 still supported as an input translation.
   685 
   686 * Renamed some theorems (the original names are also still available).
   687 
   688   expand_fun_below   ~> fun_below_iff
   689   below_fun_ext      ~> fun_belowI
   690   expand_cfun_eq     ~> cfun_eq_iff
   691   ext_cfun           ~> cfun_eqI
   692   expand_cfun_below  ~> cfun_below_iff
   693   below_cfun_ext     ~> cfun_belowI
   694   cont2cont_Rep_CFun ~> cont2cont_APP
   695 
   696 * The Abs and Rep functions for various types have changed names.
   697 Related theorem names have also changed to match. INCOMPATIBILITY.
   698 
   699   Rep_CFun  ~> Rep_cfun
   700   Abs_CFun  ~> Abs_cfun
   701   Rep_Sprod ~> Rep_sprod
   702   Abs_Sprod ~> Abs_sprod
   703   Rep_Ssum  ~> Rep_ssum
   704   Abs_Ssum  ~> Abs_ssum
   705 
   706 * Lemmas with names of the form *_defined_iff or *_strict_iff have
   707 been renamed to *_bottom_iff.  INCOMPATIBILITY.
   708 
   709 * Various changes to bisimulation/coinduction with domain package:
   710 
   711   - Definitions of "bisim" constants no longer mention definedness.
   712   - With mutual recursion, "bisim" predicate is now curried.
   713   - With mutual recursion, each type gets a separate coind theorem.
   714   - Variable names in bisim_def and coinduct rules have changed.
   715 
   716 INCOMPATIBILITY.
   717 
   718 * Case combinators generated by the domain package for type "foo" are
   719 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
   720 
   721 * Several theorems have been renamed to more accurately reflect the
   722 names of constants and types involved.  INCOMPATIBILITY.
   723 
   724   thelub_const    ~> lub_const
   725   lub_const       ~> is_lub_const
   726   thelubI         ~> lub_eqI
   727   is_lub_lub      ~> is_lubD2
   728   lubI            ~> is_lub_lub
   729   unique_lub      ~> is_lub_unique
   730   is_ub_lub       ~> is_lub_rangeD1
   731   lub_bin_chain   ~> is_lub_bin_chain
   732   lub_fun         ~> is_lub_fun
   733   thelub_fun      ~> lub_fun
   734   thelub_cfun     ~> lub_cfun
   735   thelub_Pair     ~> lub_Pair
   736   lub_cprod       ~> is_lub_prod
   737   thelub_cprod    ~> lub_prod
   738   minimal_cprod   ~> minimal_prod
   739   inst_cprod_pcpo ~> inst_prod_pcpo
   740   UU_I            ~> bottomI
   741   compact_UU      ~> compact_bottom
   742   deflation_UU    ~> deflation_bottom
   743   finite_deflation_UU ~> finite_deflation_bottom
   744 
   745 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
   746 
   747   sq_ord_less_eq_trans ~> below_eq_trans
   748   sq_ord_eq_less_trans ~> eq_below_trans
   749   refl_less            ~> below_refl
   750   trans_less           ~> below_trans
   751   antisym_less         ~> below_antisym
   752   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
   753   box_less             ~> box_below
   754   rev_trans_less       ~> rev_below_trans
   755   not_less2not_eq      ~> not_below2not_eq
   756   less_UU_iff          ~> below_UU_iff
   757   flat_less_iff        ~> flat_below_iff
   758   adm_less             ~> adm_below
   759   adm_not_less         ~> adm_not_below
   760   adm_compact_not_less ~> adm_compact_not_below
   761   less_fun_def         ~> below_fun_def
   762   expand_fun_less      ~> fun_below_iff
   763   less_fun_ext         ~> fun_belowI
   764   less_discr_def       ~> below_discr_def
   765   discr_less_eq        ~> discr_below_eq
   766   less_unit_def        ~> below_unit_def
   767   less_cprod_def       ~> below_prod_def
   768   prod_lessI           ~> prod_belowI
   769   Pair_less_iff        ~> Pair_below_iff
   770   fst_less_iff         ~> fst_below_iff
   771   snd_less_iff         ~> snd_below_iff
   772   expand_cfun_less     ~> cfun_below_iff
   773   less_cfun_ext        ~> cfun_belowI
   774   injection_less       ~> injection_below
   775   less_up_def          ~> below_up_def
   776   not_Iup_less         ~> not_Iup_below
   777   Iup_less             ~> Iup_below
   778   up_less              ~> up_below
   779   Def_inject_less_eq   ~> Def_below_Def
   780   Def_less_is_eq       ~> Def_below_iff
   781   spair_less_iff       ~> spair_below_iff
   782   less_sprod           ~> below_sprod
   783   spair_less           ~> spair_below
   784   sfst_less_iff        ~> sfst_below_iff
   785   ssnd_less_iff        ~> ssnd_below_iff
   786   fix_least_less       ~> fix_least_below
   787   dist_less_one        ~> dist_below_one
   788   less_ONE             ~> below_ONE
   789   ONE_less_iff         ~> ONE_below_iff
   790   less_sinlD           ~> below_sinlD
   791   less_sinrD           ~> below_sinrD
   792 
   793 
   794 *** FOL and ZF ***
   795 
   796 * All constant names are now qualified internally and use proper
   797 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
   798 
   799 
   800 *** ML ***
   801 
   802 * Antiquotation @{assert} inlines a function bool -> unit that raises
   803 Fail if the argument is false.  Due to inlining the source position of
   804 failed assertions is included in the error output.
   805 
   806 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
   807 text is in practice always evaluated with a stable theory checkpoint.
   808 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
   809 
   810 * Antiquotation @{theory A} refers to theory A from the ancestry of
   811 the current context, not any accidental theory loader state as before.
   812 Potential INCOMPATIBILITY, subtle change in semantics.
   813 
   814 * Syntax.pretty_priority (default 0) configures the required priority
   815 of pretty-printed output and thus affects insertion of parentheses.
   816 
   817 * Syntax.default_root (default "any") configures the inner syntax
   818 category (nonterminal symbol) for parsing of terms.
   819 
   820 * Former exception Library.UnequalLengths now coincides with
   821 ListPair.UnequalLengths.
   822 
   823 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
   824 main functionality is provided by structure Simplifier.
   825 
   826 * Renamed raw "explode" function to "raw_explode" to emphasize its
   827 meaning.  Note that internally to Isabelle, Symbol.explode is used in
   828 almost all situations.
   829 
   830 * Discontinued obsolete function sys_error and exception SYS_ERROR.
   831 See implementation manual for further details on exceptions in
   832 Isabelle/ML.
   833 
   834 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
   835 meaning.
   836 
   837 * Renamed structure PureThy to Pure_Thy and moved most of its
   838 operations to structure Global_Theory, to emphasize that this is
   839 rarely-used global-only stuff.
   840 
   841 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
   842 instead (or tracing for high-volume output).
   843 
   844 * Configuration option show_question_marks only affects regular pretty
   845 printing of types and terms, not raw Term.string_of_vname.
   846 
   847 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
   848 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
   849 @{thms} for most purposes.
   850 
   851 * ML structure Unsynchronized is never opened, not even in Isar
   852 interaction mode as before.  Old Unsynchronized.set etc. have been
   853 discontinued -- use plain := instead.  This should be *rare* anyway,
   854 since modern tools always work via official context data, notably
   855 configuration options.
   856 
   857 * Parallel and asynchronous execution requires special care concerning
   858 interrupts.  Structure Exn provides some convenience functions that
   859 avoid working directly with raw Interrupt.  User code must not absorb
   860 interrupts -- intermediate handling (for cleanup etc.) needs to be
   861 followed by re-raising of the original exception.  Another common
   862 source of mistakes are "handle _" patterns, which make the meaning of
   863 the program subject to physical effects of the environment.
   864 
   865 
   866 
   867 New in Isabelle2009-2 (June 2010)
   868 ---------------------------------
   869 
   870 *** General ***
   871 
   872 * Authentic syntax for *all* logical entities (type classes, type
   873 constructors, term constants): provides simple and robust
   874 correspondence between formal entities and concrete syntax.  Within
   875 the parse tree / AST representations, "constants" are decorated by
   876 their category (class, type, const) and spelled out explicitly with
   877 their full internal name.
   878 
   879 Substantial INCOMPATIBILITY concerning low-level syntax declarations
   880 and translations (translation rules and translation functions in ML).
   881 Some hints on upgrading:
   882 
   883   - Many existing uses of 'syntax' and 'translations' can be replaced
   884     by more modern 'type_notation', 'notation' and 'abbreviation',
   885     which are independent of this issue.
   886 
   887   - 'translations' require markup within the AST; the term syntax
   888     provides the following special forms:
   889 
   890       CONST c   -- produces syntax version of constant c from context
   891       XCONST c  -- literally c, checked as constant from context
   892       c         -- literally c, if declared by 'syntax'
   893 
   894     Plain identifiers are treated as AST variables -- occasionally the
   895     system indicates accidental variables via the error "rhs contains
   896     extra variables".
   897 
   898     Type classes and type constructors are marked according to their
   899     concrete syntax.  Some old translations rules need to be written
   900     for the "type" category, using type constructor application
   901     instead of pseudo-term application of the default category
   902     "logic".
   903 
   904   - 'parse_translation' etc. in ML may use the following
   905     antiquotations:
   906 
   907       @{class_syntax c}   -- type class c within parse tree / AST
   908       @{term_syntax c}    -- type constructor c within parse tree / AST
   909       @{const_syntax c}   -- ML version of "CONST c" above
   910       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
   911 
   912   - Literal types within 'typed_print_translations', i.e. those *not*
   913     represented as pseudo-terms are represented verbatim.  Use @{class
   914     c} or @{type_name c} here instead of the above syntax
   915     antiquotations.
   916 
   917 Note that old non-authentic syntax was based on unqualified base
   918 names, so all of the above "constant" names would coincide.  Recall
   919 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
   920 diagnose syntax problems.
   921 
   922 * Type constructors admit general mixfix syntax, not just infix.
   923 
   924 * Concrete syntax may be attached to local entities without a proof
   925 body, too.  This works via regular mixfix annotations for 'fix',
   926 'def', 'obtain' etc. or via the explicit 'write' command, which is
   927 similar to the 'notation' command in theory specifications.
   928 
   929 * Discontinued unnamed infix syntax (legacy feature for many years) --
   930 need to specify constant name and syntax separately.  Internal ML
   931 datatype constructors have been renamed from InfixName to Infix etc.
   932 Minor INCOMPATIBILITY.
   933 
   934 * Schematic theorem statements need to be explicitly markup as such,
   935 via commands 'schematic_lemma', 'schematic_theorem',
   936 'schematic_corollary'.  Thus the relevance of the proof is made
   937 syntactically clear, which impacts performance in a parallel or
   938 asynchronous interactive environment.  Minor INCOMPATIBILITY.
   939 
   940 * Use of cumulative prems via "!" in some proof methods has been
   941 discontinued (old legacy feature).
   942 
   943 * References 'trace_simp' and 'debug_simp' have been replaced by
   944 configuration options stored in the context. Enabling tracing (the
   945 case of debugging is similar) in proofs works via
   946 
   947   using [[trace_simp = true]]
   948 
   949 Tracing is then active for all invocations of the simplifier in
   950 subsequent goal refinement steps. Tracing may also still be enabled or
   951 disabled via the ProofGeneral settings menu.
   952 
   953 * Separate commands 'hide_class', 'hide_type', 'hide_const',
   954 'hide_fact' replace the former 'hide' KIND command.  Minor
   955 INCOMPATIBILITY.
   956 
   957 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
   958 more efficient than combinations with -q1 or -q2.
   959 
   960 
   961 *** Pure ***
   962 
   963 * Proofterms record type-class reasoning explicitly, using the
   964 "unconstrain" operation internally.  This eliminates all sort
   965 constraints from a theorem and proof, introducing explicit
   966 OFCLASS-premises.  On the proof term level, this operation is
   967 automatically applied at theorem boundaries, such that closed proofs
   968 are always free of sort constraints.  INCOMPATIBILITY for tools that
   969 inspect proof terms.
   970 
   971 * Local theory specifications may depend on extra type variables that
   972 are not present in the result type -- arguments TYPE('a) :: 'a itself
   973 are added internally.  For example:
   974 
   975   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
   976 
   977 * Predicates of locales introduced by classes carry a mandatory
   978 "class" prefix.  INCOMPATIBILITY.
   979 
   980 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
   981 
   982 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
   983 'class' instead.
   984 
   985 * Command 'code_reflect' allows to incorporate generated ML code into
   986 runtime environment; replaces immature code_datatype antiquotation.
   987 INCOMPATIBILITY.
   988 
   989 * Code generator: simple concept for abstract datatypes obeying
   990 invariants.
   991 
   992 * Code generator: details of internal data cache have no impact on the
   993 user space functionality any longer.
   994 
   995 * Methods "unfold_locales" and "intro_locales" ignore non-locale
   996 subgoals.  This is more appropriate for interpretations with 'where'.
   997 INCOMPATIBILITY.
   998 
   999 * Command 'example_proof' opens an empty proof body.  This allows to
  1000 experiment with Isar, without producing any persistent result.
  1001 
  1002 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  1003 within a local theory context, with explicit checking of the
  1004 constructors involved (in contrast to the raw 'syntax' versions).
  1005 
  1006 * Commands 'types' and 'typedecl' now work within a local theory
  1007 context -- without introducing dependencies on parameters or
  1008 assumptions, which is not possible in Isabelle/Pure.
  1009 
  1010 * Command 'defaultsort' has been renamed to 'default_sort', it works
  1011 within a local theory context.  Minor INCOMPATIBILITY.
  1012 
  1013 
  1014 *** HOL ***
  1015 
  1016 * Command 'typedef' now works within a local theory context -- without
  1017 introducing dependencies on parameters or assumptions, which is not
  1018 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  1019 contain multiple interpretations of local typedefs (with different
  1020 non-emptiness proofs), even in a global theory context.
  1021 
  1022 * New package for quotient types.  Commands 'quotient_type' and
  1023 'quotient_definition' may be used for defining types and constants by
  1024 quotient constructions.  An example is the type of integers created by
  1025 quotienting pairs of natural numbers:
  1026 
  1027   fun
  1028     intrel :: "(nat * nat) => (nat * nat) => bool"
  1029   where
  1030     "intrel (x, y) (u, v) = (x + v = u + y)"
  1031 
  1032   quotient_type int = "nat * nat" / intrel
  1033     by (auto simp add: equivp_def expand_fun_eq)
  1034 
  1035   quotient_definition
  1036     "0::int" is "(0::nat, 0::nat)"
  1037 
  1038 The method "lifting" can be used to lift of theorems from the
  1039 underlying "raw" type to the quotient type.  The example
  1040 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  1041 construction and provides a reasoning infrastructure for finite sets.
  1042 
  1043 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  1044 clash with new theory Quotient in Main HOL.
  1045 
  1046 * Moved the SMT binding into the main HOL session, eliminating
  1047 separate HOL-SMT session.
  1048 
  1049 * List membership infix mem operation is only an input abbreviation.
  1050 INCOMPATIBILITY.
  1051 
  1052 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  1053 for future developements; former Library/Word.thy is still present in
  1054 the AFP entry RSAPPS.
  1055 
  1056 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  1057 longer shadowed.  INCOMPATIBILITY.
  1058 
  1059 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  1060 INCOMPATIBILITY.
  1061 
  1062 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  1063 INCOMPATIBILITY.
  1064 
  1065 * Dropped normalizing_semiring etc; use the facts in semiring classes
  1066 instead.  INCOMPATIBILITY.
  1067 
  1068 * Dropped several real-specific versions of lemmas about floor and
  1069 ceiling; use the generic lemmas from theory "Archimedean_Field"
  1070 instead.  INCOMPATIBILITY.
  1071 
  1072   floor_number_of_eq         ~> floor_number_of
  1073   le_floor_eq_number_of      ~> number_of_le_floor
  1074   le_floor_eq_zero           ~> zero_le_floor
  1075   le_floor_eq_one            ~> one_le_floor
  1076   floor_less_eq_number_of    ~> floor_less_number_of
  1077   floor_less_eq_zero         ~> floor_less_zero
  1078   floor_less_eq_one          ~> floor_less_one
  1079   less_floor_eq_number_of    ~> number_of_less_floor
  1080   less_floor_eq_zero         ~> zero_less_floor
  1081   less_floor_eq_one          ~> one_less_floor
  1082   floor_le_eq_number_of      ~> floor_le_number_of
  1083   floor_le_eq_zero           ~> floor_le_zero
  1084   floor_le_eq_one            ~> floor_le_one
  1085   floor_subtract_number_of   ~> floor_diff_number_of
  1086   floor_subtract_one         ~> floor_diff_one
  1087   ceiling_number_of_eq       ~> ceiling_number_of
  1088   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  1089   ceiling_le_zero_eq         ~> ceiling_le_zero
  1090   ceiling_le_eq_one          ~> ceiling_le_one
  1091   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  1092   less_ceiling_eq_zero       ~> zero_less_ceiling
  1093   less_ceiling_eq_one        ~> one_less_ceiling
  1094   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  1095   ceiling_less_eq_zero       ~> ceiling_less_zero
  1096   ceiling_less_eq_one        ~> ceiling_less_one
  1097   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  1098   le_ceiling_eq_zero         ~> zero_le_ceiling
  1099   le_ceiling_eq_one          ~> one_le_ceiling
  1100   ceiling_subtract_number_of ~> ceiling_diff_number_of
  1101   ceiling_subtract_one       ~> ceiling_diff_one
  1102 
  1103 * Theory "Finite_Set": various folding_XXX locales facilitate the
  1104 application of the various fold combinators on finite sets.
  1105 
  1106 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  1107 provides abstract red-black tree type which is backed by "RBT_Impl" as
  1108 implementation.  INCOMPATIBILTY.
  1109 
  1110 * Theory Library/Coinductive_List has been removed -- superseded by
  1111 AFP/thys/Coinductive.
  1112 
  1113 * Theory PReal, including the type "preal" and related operations, has
  1114 been removed.  INCOMPATIBILITY.
  1115 
  1116 * Real: new development using Cauchy Sequences.
  1117 
  1118 * Split off theory "Big_Operators" containing setsum, setprod,
  1119 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  1120 
  1121 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  1122 "Int" etc.  INCOMPATIBILITY.
  1123 
  1124 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  1125 
  1126 * New set of rules "ac_simps" provides combined assoc / commute
  1127 rewrites for all interpretations of the appropriate generic locales.
  1128 
  1129 * Renamed theory "OrderedGroup" to "Groups" and split theory
  1130 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  1131 appropriate and more consistent names suitable for name prefixes
  1132 within the HOL theories.  INCOMPATIBILITY.
  1133 
  1134 * Some generic constants have been put to appropriate theories:
  1135   - less_eq, less: Orderings
  1136   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  1137   - inverse, divide: Rings
  1138 INCOMPATIBILITY.
  1139 
  1140 * More consistent naming of type classes involving orderings (and
  1141 lattices):
  1142 
  1143     lower_semilattice                   ~> semilattice_inf
  1144     upper_semilattice                   ~> semilattice_sup
  1145 
  1146     dense_linear_order                  ~> dense_linorder
  1147 
  1148     pordered_ab_group_add               ~> ordered_ab_group_add
  1149     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  1150     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  1151     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  1152     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  1153     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  1154     pordered_cancel_semiring            ~> ordered_cancel_semiring
  1155     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  1156     pordered_comm_ring                  ~> ordered_comm_ring
  1157     pordered_comm_semiring              ~> ordered_comm_semiring
  1158     pordered_ring                       ~> ordered_ring
  1159     pordered_ring_abs                   ~> ordered_ring_abs
  1160     pordered_semiring                   ~> ordered_semiring
  1161 
  1162     ordered_ab_group_add                ~> linordered_ab_group_add
  1163     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  1164     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  1165     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  1166     ordered_field                       ~> linordered_field
  1167     ordered_field_no_lb                 ~> linordered_field_no_lb
  1168     ordered_field_no_ub                 ~> linordered_field_no_ub
  1169     ordered_field_dense_linear_order    ~> dense_linordered_field
  1170     ordered_idom                        ~> linordered_idom
  1171     ordered_ring                        ~> linordered_ring
  1172     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  1173     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  1174     ordered_ring_strict                 ~> linordered_ring_strict
  1175     ordered_semidom                     ~> linordered_semidom
  1176     ordered_semiring                    ~> linordered_semiring
  1177     ordered_semiring_1                  ~> linordered_semiring_1
  1178     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  1179     ordered_semiring_strict             ~> linordered_semiring_strict
  1180 
  1181   The following slightly odd type classes have been moved to a
  1182   separate theory Library/Lattice_Algebras:
  1183 
  1184     lordered_ab_group_add               ~> lattice_ab_group_add
  1185     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  1186     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  1187     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  1188     lordered_ring                       ~> lattice_ring
  1189 
  1190 INCOMPATIBILITY.
  1191 
  1192 * Refined field classes:
  1193   - classes division_ring_inverse_zero, field_inverse_zero,
  1194     linordered_field_inverse_zero include rule inverse 0 = 0 --
  1195     subsumes former division_by_zero class;
  1196   - numerous lemmas have been ported from field to division_ring.
  1197 INCOMPATIBILITY.
  1198 
  1199 * Refined algebra theorem collections:
  1200   - dropped theorem group group_simps, use algebra_simps instead;
  1201   - dropped theorem group ring_simps, use field_simps instead;
  1202   - proper theorem collection field_simps subsumes former theorem
  1203     groups field_eq_simps and field_simps;
  1204   - dropped lemma eq_minus_self_iff which is a duplicate for
  1205     equal_neg_zero.
  1206 INCOMPATIBILITY.
  1207 
  1208 * Theory Finite_Set and List: some lemmas have been generalized from
  1209 sets to lattices:
  1210 
  1211   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  1212   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  1213   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  1214   union_Union_fold_union        ~> sup_Sup_fold_sup
  1215   Inter_fold_inter              ~> Inf_fold_inf
  1216   Union_fold_union              ~> Sup_fold_sup
  1217   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  1218   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  1219   INTER_fold_inter              ~> INFI_fold_inf
  1220   UNION_fold_union              ~> SUPR_fold_sup
  1221 
  1222 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  1223 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  1224 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  1225 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  1226 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  1227 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  1228 
  1229 * Reorganized theory Multiset: swapped notation of pointwise and
  1230 multiset order:
  1231 
  1232   - pointwise ordering is instance of class order with standard syntax
  1233     <= and <;
  1234   - multiset ordering has syntax <=# and <#; partial order properties
  1235     are provided by means of interpretation with prefix
  1236     multiset_order;
  1237   - less duplication, less historical organization of sections,
  1238     conversion from associations lists to multisets, rudimentary code
  1239     generation;
  1240   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  1241     if needed.
  1242 
  1243 Renamed:
  1244 
  1245   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  1246   multi_count_ext  ~>  multiset_ext
  1247   diff_union_inverse2  ~>  diff_union_cancelR
  1248 
  1249 INCOMPATIBILITY.
  1250 
  1251 * Theory Permutation: replaced local "remove" by List.remove1.
  1252 
  1253 * Code generation: ML and OCaml code is decorated with signatures.
  1254 
  1255 * Theory List: added transpose.
  1256 
  1257 * Library/Nat_Bijection.thy is a collection of bijective functions
  1258 between nat and other types, which supersedes the older libraries
  1259 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  1260 
  1261   Constants:
  1262   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  1263   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  1264   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  1265   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  1266   Countable.pair_encode           ~> prod_encode
  1267   NatIso.prod2nat                 ~> prod_encode
  1268   NatIso.nat2prod                 ~> prod_decode
  1269   NatIso.sum2nat                  ~> sum_encode
  1270   NatIso.nat2sum                  ~> sum_decode
  1271   NatIso.list2nat                 ~> list_encode
  1272   NatIso.nat2list                 ~> list_decode
  1273   NatIso.set2nat                  ~> set_encode
  1274   NatIso.nat2set                  ~> set_decode
  1275 
  1276   Lemmas:
  1277   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  1278   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  1279   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  1280   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  1281   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  1282   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  1283   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  1284   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  1285   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  1286   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  1287   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  1288   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  1289   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  1290 
  1291 * Sledgehammer:
  1292   - Renamed ATP commands:
  1293     atp_info     ~> sledgehammer running_atps
  1294     atp_kill     ~> sledgehammer kill_atps
  1295     atp_messages ~> sledgehammer messages
  1296     atp_minimize ~> sledgehammer minimize
  1297     print_atps   ~> sledgehammer available_atps
  1298     INCOMPATIBILITY.
  1299   - Added user's manual ("isabelle doc sledgehammer").
  1300   - Added option syntax and "sledgehammer_params" to customize
  1301     Sledgehammer's behavior.  See the manual for details.
  1302   - Modified the Isar proof reconstruction code so that it produces
  1303     direct proofs rather than proofs by contradiction.  (This feature
  1304     is still experimental.)
  1305   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  1306     full-typed mode.
  1307   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  1308 
  1309 * Nitpick:
  1310   - Added and implemented "binary_ints" and "bits" options.
  1311   - Added "std" option and implemented support for nonstandard models.
  1312   - Added and implemented "finitize" option to improve the precision
  1313     of infinite datatypes based on a monotonicity analysis.
  1314   - Added support for quotient types.
  1315   - Added support for "specification" and "ax_specification"
  1316     constructs.
  1317   - Added support for local definitions (for "function" and
  1318     "termination" proofs).
  1319   - Added support for term postprocessors.
  1320   - Optimized "Multiset.multiset" and "FinFun.finfun".
  1321   - Improved efficiency of "destroy_constrs" optimization.
  1322   - Fixed soundness bugs related to "destroy_constrs" optimization and
  1323     record getters.
  1324   - Fixed soundness bug related to higher-order constructors.
  1325   - Fixed soundness bug when "full_descrs" is enabled.
  1326   - Improved precision of set constructs.
  1327   - Added "atoms" option.
  1328   - Added cache to speed up repeated Kodkod invocations on the same
  1329     problems.
  1330   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  1331     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  1332     "SAT4J_Light".  INCOMPATIBILITY.
  1333   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  1334     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  1335   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  1336 
  1337 * Method "induct" now takes instantiations of the form t, where t is not
  1338   a variable, as a shorthand for "x == t", where x is a fresh variable.
  1339   If this is not intended, t has to be enclosed in parentheses.
  1340   By default, the equalities generated by definitional instantiations
  1341   are pre-simplified, which may cause parameters of inductive cases
  1342   to disappear, or may even delete some of the inductive cases.
  1343   Use "induct (no_simp)" instead of "induct" to restore the old
  1344   behaviour. The (no_simp) option is also understood by the "cases"
  1345   and "nominal_induct" methods, which now perform pre-simplification, too.
  1346   INCOMPATIBILITY.
  1347 
  1348 
  1349 *** HOLCF ***
  1350 
  1351 * Variable names in lemmas generated by the domain package have
  1352 changed; the naming scheme is now consistent with the HOL datatype
  1353 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  1354 
  1355 * The domain package no longer defines the function "foo_copy" for
  1356 recursive domain "foo".  The reach lemma is now stated directly in
  1357 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  1358 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  1359 
  1360 * Most definedness lemmas generated by the domain package (previously
  1361 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  1362 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  1363 Proofs that used definedness lemmas as intro rules may break,
  1364 potential INCOMPATIBILITY.
  1365 
  1366 * Induction and casedist rules generated by the domain package now
  1367 declare proper case_names (one called "bottom", and one named for each
  1368 constructor).  INCOMPATIBILITY.
  1369 
  1370 * For mutually-recursive domains, separate "reach" and "take_lemma"
  1371 rules are generated for each domain, INCOMPATIBILITY.
  1372 
  1373   foo_bar.reach       ~> foo.reach  bar.reach
  1374   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  1375 
  1376 * Some lemmas generated by the domain package have been renamed for
  1377 consistency with the datatype package, INCOMPATIBILITY.
  1378 
  1379   foo.ind        ~> foo.induct
  1380   foo.finite_ind ~> foo.finite_induct
  1381   foo.coind      ~> foo.coinduct
  1382   foo.casedist   ~> foo.exhaust
  1383   foo.exhaust    ~> foo.nchotomy
  1384 
  1385 * For consistency with other definition packages, the fixrec package
  1386 now generates qualified theorem names, INCOMPATIBILITY.
  1387 
  1388   foo_simps  ~> foo.simps
  1389   foo_unfold ~> foo.unfold
  1390   foo_induct ~> foo.induct
  1391 
  1392 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  1393 method and internal fixrec proofs now use the default simpset instead.
  1394 INCOMPATIBILITY.
  1395 
  1396 * The "contlub" predicate has been removed.  Proof scripts should use
  1397 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  1398 
  1399 * The "admw" predicate has been removed, INCOMPATIBILITY.
  1400 
  1401 * The constants cpair, cfst, and csnd have been removed in favor of
  1402 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  1403 
  1404 
  1405 *** ML ***
  1406 
  1407 * Antiquotations for basic formal entities:
  1408 
  1409     @{class NAME}         -- type class
  1410     @{class_syntax NAME}  -- syntax representation of the above
  1411 
  1412     @{type_name NAME}     -- logical type
  1413     @{type_abbrev NAME}   -- type abbreviation
  1414     @{nonterminal NAME}   -- type of concrete syntactic category
  1415     @{type_syntax NAME}   -- syntax representation of any of the above
  1416 
  1417     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  1418     @{const_abbrev NAME}  -- abbreviated constant
  1419     @{const_syntax NAME}  -- syntax representation of any of the above
  1420 
  1421 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  1422 syntax constant (cf. 'syntax' command).
  1423 
  1424 * Antiquotation @{make_string} inlines a function to print arbitrary
  1425 values similar to the ML toplevel.  The result is compiler dependent
  1426 and may fall back on "?" in certain situations.
  1427 
  1428 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  1429 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  1430 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  1431 not work with the asynchronous Isar document model.
  1432 
  1433 * Configuration options now admit dynamic default values, depending on
  1434 the context or even global references.
  1435 
  1436 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  1437 uses an efficient external library if available (for Poly/ML).
  1438 
  1439 * Renamed some important ML structures, while keeping the old names
  1440 for some time as aliases within the structure Legacy:
  1441 
  1442   OuterKeyword  ~>  Keyword
  1443   OuterLex      ~>  Token
  1444   OuterParse    ~>  Parse
  1445   OuterSyntax   ~>  Outer_Syntax
  1446   PrintMode     ~>  Print_Mode
  1447   SpecParse     ~>  Parse_Spec
  1448   ThyInfo       ~>  Thy_Info
  1449   ThyLoad       ~>  Thy_Load
  1450   ThyOutput     ~>  Thy_Output
  1451   TypeInfer     ~>  Type_Infer
  1452 
  1453 Note that "open Legacy" simplifies porting of sources, but forgetting
  1454 to remove it again will complicate porting again in the future.
  1455 
  1456 * Most operations that refer to a global context are named
  1457 accordingly, e.g. Simplifier.global_context or
  1458 ProofContext.init_global.  There are some situations where a global
  1459 context actually works, but under normal circumstances one needs to
  1460 pass the proper local context through the code!
  1461 
  1462 * Discontinued old TheoryDataFun with its copy/init operation -- data
  1463 needs to be pure.  Functor Theory_Data_PP retains the traditional
  1464 Pretty.pp argument to merge, which is absent in the standard
  1465 Theory_Data version.
  1466 
  1467 * Sorts.certify_sort and derived "cert" operations for types and terms
  1468 no longer minimize sorts.  Thus certification at the boundary of the
  1469 inference kernel becomes invariant under addition of class relations,
  1470 which is an important monotonicity principle.  Sorts are now minimized
  1471 in the syntax layer only, at the boundary between the end-user and the
  1472 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  1473 explicitly in rare situations.
  1474 
  1475 * Renamed old-style Drule.standard to Drule.export_without_context, to
  1476 emphasize that this is in no way a standard operation.
  1477 INCOMPATIBILITY.
  1478 
  1479 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  1480 usual for resolution.  Rare INCOMPATIBILITY.
  1481 
  1482 * Renamed varify/unvarify operations to varify_global/unvarify_global
  1483 to emphasize that these only work in a global situation (which is
  1484 quite rare).
  1485 
  1486 * Curried take and drop in library.ML; negative length is interpreted
  1487 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  1488 
  1489 * Proof terms: type substitutions on proof constants now use canonical
  1490 order of type variables.  INCOMPATIBILITY for tools working with proof
  1491 terms.
  1492 
  1493 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  1494 may no longer carry premises.  User-level specifications are
  1495 transformed accordingly by Thm.add_axiom/add_def.
  1496 
  1497 
  1498 *** System ***
  1499 
  1500 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  1501 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  1502 proof terms are enabled unconditionally in the new HOL-Proofs image.
  1503 
  1504 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  1505 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  1506 respectively.
  1507 
  1508 * Old lib/scripts/polyml-platform is superseded by the
  1509 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  1510 variant, even on a 64 bit machine.  The following example setting
  1511 prefers 64 bit if available:
  1512 
  1513   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  1514 
  1515 * The preliminary Isabelle/jEdit application demonstrates the emerging
  1516 Isabelle/Scala layer for advanced prover interaction and integration.
  1517 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  1518 component.
  1519 
  1520 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  1521 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  1522 similar to the default assignment of the document preparation system
  1523 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  1524 provides some operations for direct access to the font without asking
  1525 the user for manual installation.
  1526 
  1527 
  1528 
  1529 New in Isabelle2009-1 (December 2009)
  1530 -------------------------------------
  1531 
  1532 *** General ***
  1533 
  1534 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  1535 one backslash should be used, even in ML sources.
  1536 
  1537 
  1538 *** Pure ***
  1539 
  1540 * Locale interpretation propagates mixins along the locale hierarchy.
  1541 The currently only available mixins are the equations used to map
  1542 local definitions to terms of the target domain of an interpretation.
  1543 
  1544 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  1545 loc" to print all interpretations of locale "loc" in the theory.
  1546 Interpretations in proofs are not shown.
  1547 
  1548 * Thoroughly revised locales tutorial.  New section on conditional
  1549 interpretation.
  1550 
  1551 * On instantiation of classes, remaining undefined class parameters
  1552 are formally declared.  INCOMPATIBILITY.
  1553 
  1554 
  1555 *** Document preparation ***
  1556 
  1557 * New generalized style concept for printing terms: @{foo (style) ...}
  1558 instead of @{foo_style style ...}  (old form is still retained for
  1559 backward compatibility).  Styles can be also applied for
  1560 antiquotations prop, term_type and typeof.
  1561 
  1562 
  1563 *** HOL ***
  1564 
  1565 * New proof method "smt" for a combination of first-order logic with
  1566 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  1567 fixed-size bitvectors; there is also basic support for higher-order
  1568 features (esp. lambda abstractions).  It is an incomplete decision
  1569 procedure based on external SMT solvers using the oracle mechanism;
  1570 for the SMT solver Z3, this method is proof-producing.  Certificates
  1571 are provided to avoid calling the external solvers solely for
  1572 re-checking proofs.  Due to a remote SMT service there is no need for
  1573 installing SMT solvers locally.  See src/HOL/SMT.
  1574 
  1575 * New commands to load and prove verification conditions generated by
  1576 the Boogie program verifier or derived systems (e.g. the Verifying C
  1577 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1578 
  1579 * New counterexample generator tool 'nitpick' based on the Kodkod
  1580 relational model finder.  See src/HOL/Tools/Nitpick and
  1581 src/HOL/Nitpick_Examples.
  1582 
  1583 * New commands 'code_pred' and 'values' to invoke the predicate
  1584 compiler and to enumerate values of inductive predicates.
  1585 
  1586 * A tabled implementation of the reflexive transitive closure.
  1587 
  1588 * New implementation of quickcheck uses generic code generator;
  1589 default generators are provided for all suitable HOL types, records
  1590 and datatypes.  Old quickcheck can be re-activated importing theory
  1591 Library/SML_Quickcheck.
  1592 
  1593 * New testing tool Mirabelle for automated proof tools.  Applies
  1594 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1595 every proof step in a theory.  To be used in batch mode via the
  1596 "mirabelle" utility.
  1597 
  1598 * New proof method "sos" (sum of squares) for nonlinear real
  1599 arithmetic (originally due to John Harison). It requires theory
  1600 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1601 works well in practice on quantifier-free real arithmetic with +, -,
  1602 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1603 inequalities between polynomials.  It makes use of external
  1604 semidefinite programming solvers.  Method "sos" generates a
  1605 certificate that can be pasted into the proof thus avoiding the need
  1606 to call an external tool every time the proof is checked.  See
  1607 src/HOL/Library/Sum_Of_Squares.
  1608 
  1609 * New method "linarith" invokes existing linear arithmetic decision
  1610 procedure only.
  1611 
  1612 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1613 
  1614 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1615 Causes full type information to be output to the ATPs.  This slows
  1616 ATPs down considerably but eliminates a source of unsound "proofs"
  1617 that fail later.
  1618 
  1619 * New method "metisFT": A version of metis that uses full type
  1620 information in order to avoid failures of proof reconstruction.
  1621 
  1622 * New evaluator "approximate" approximates an real valued term using
  1623 the same method as the approximation method.
  1624 
  1625 * Method "approximate" now supports arithmetic expressions as
  1626 boundaries of intervals and implements interval splitting and Taylor
  1627 series expansion.
  1628 
  1629 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1630 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1631 
  1632 * New theory SupInf of the supremum and infimum operators for sets of
  1633 reals.
  1634 
  1635 * New theory Probability, which contains a development of measure
  1636 theory, eventually leading to Lebesgue integration and probability.
  1637 
  1638 * Extended Multivariate Analysis to include derivation and Brouwer's
  1639 fixpoint theorem.
  1640 
  1641 * Reorganization of number theory, INCOMPATIBILITY:
  1642   - new number theory development for nat and int, in theories Divides
  1643     and GCD as well as in new session Number_Theory
  1644   - some constants and facts now suffixed with _nat and _int
  1645     accordingly
  1646   - former session NumberTheory now named Old_Number_Theory, including
  1647     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1648   - moved theory Pocklington from src/HOL/Library to
  1649     src/HOL/Old_Number_Theory
  1650 
  1651 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1652 lcm of finite and infinite sets. It is shown that they form a complete
  1653 lattice.
  1654 
  1655 * Class semiring_div requires superclass no_zero_divisors and proof of
  1656 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1657 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1658 generalized to class semiring_div, subsuming former theorems
  1659 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1660 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1661 INCOMPATIBILITY.
  1662 
  1663 * Refinements to lattice classes and sets:
  1664   - less default intro/elim rules in locale variant, more default
  1665     intro/elim rules in class variant: more uniformity
  1666   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1667     le_inf_iff
  1668   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1669     sup_aci)
  1670   - renamed ACI to inf_sup_aci
  1671   - new class "boolean_algebra"
  1672   - class "complete_lattice" moved to separate theory
  1673     "Complete_Lattice"; corresponding constants (and abbreviations)
  1674     renamed and with authentic syntax:
  1675     Set.Inf ~>    Complete_Lattice.Inf
  1676     Set.Sup ~>    Complete_Lattice.Sup
  1677     Set.INFI ~>   Complete_Lattice.INFI
  1678     Set.SUPR ~>   Complete_Lattice.SUPR
  1679     Set.Inter ~>  Complete_Lattice.Inter
  1680     Set.Union ~>  Complete_Lattice.Union
  1681     Set.INTER ~>  Complete_Lattice.INTER
  1682     Set.UNION ~>  Complete_Lattice.UNION
  1683   - authentic syntax for
  1684     Set.Pow
  1685     Set.image
  1686   - mere abbreviations:
  1687     Set.empty               (for bot)
  1688     Set.UNIV                (for top)
  1689     Set.inter               (for inf, formerly Set.Int)
  1690     Set.union               (for sup, formerly Set.Un)
  1691     Complete_Lattice.Inter  (for Inf)
  1692     Complete_Lattice.Union  (for Sup)
  1693     Complete_Lattice.INTER  (for INFI)
  1694     Complete_Lattice.UNION  (for SUPR)
  1695   - object-logic definitions as far as appropriate
  1696 
  1697 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1698 Un_subset_iff are explicitly deleted as default simp rules; then also
  1699 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1700 deleted to achieve the desired effect.
  1701 
  1702 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1703 rules by default any longer; the same applies to min_max.inf_absorb1
  1704 etc.  INCOMPATIBILITY.
  1705 
  1706 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1707 pred_set_conv by default.  INCOMPATIBILITY.
  1708 
  1709 * Power operations on relations and functions are now one dedicated
  1710 constant "compow" with infix syntax "^^".  Power operation on
  1711 multiplicative monoids retains syntax "^" and is now defined generic
  1712 in class power.  INCOMPATIBILITY.
  1713 
  1714 * Relation composition "R O S" now has a more standard argument order:
  1715 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1716 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1717 break, since the O_assoc rule was not rewritten like this.  Fix using
  1718 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1719 
  1720 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1721 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1722 INCOMPATIBILITY.
  1723 
  1724 * Most rules produced by inductive and datatype package have mandatory
  1725 prefixes.  INCOMPATIBILITY.
  1726 
  1727 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1728 the attribute of the same name.  Each of the theorems in the list
  1729 DERIV_intros assumes composition with an additional function and
  1730 matches a variable to the derivative, which has to be solved by the
  1731 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1732 of most elementary terms.  Former Maclauren.DERIV_tac and
  1733 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1734 INCOMPATIBILITY.
  1735 
  1736 * Code generator attributes follow the usual underscore convention:
  1737     code_unfold     replaces    code unfold
  1738     code_post       replaces    code post
  1739     etc.
  1740   INCOMPATIBILITY.
  1741 
  1742 * Renamed methods:
  1743     sizechange -> size_change
  1744     induct_scheme -> induction_schema
  1745   INCOMPATIBILITY.
  1746 
  1747 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1748 INCOMPATIBILITY, use "undefined" directly.
  1749 
  1750 * Renamed theorems:
  1751     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1752     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1753     Suc_plus1 -> Suc_eq_plus1
  1754     *anti_sym -> *antisym*
  1755     vector_less_eq_def -> vector_le_def
  1756   INCOMPATIBILITY.
  1757 
  1758 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1759 INCOMPATIBILITY.
  1760 
  1761 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1762 INCOMPATIBILITY.
  1763 
  1764 
  1765 *** HOLCF ***
  1766 
  1767 * Theory Representable defines a class "rep" of domains that are
  1768 representable (via an ep-pair) in the universal domain type "udom".
  1769 Instances are provided for all type constructors defined in HOLCF.
  1770 
  1771 * The 'new_domain' command is a purely definitional version of the
  1772 domain package, for representable domains.  Syntax is identical to the
  1773 old domain package.  The 'new_domain' package also supports indirect
  1774 recursion using previously-defined type constructors.  See
  1775 src/HOLCF/ex/New_Domain.thy for examples.
  1776 
  1777 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1778 on the left-hand side of an equation, and then performs
  1779 simplification.  Rewriting is done using rules declared with the
  1780 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1781 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1782 
  1783 * The pattern-match compiler in 'fixrec' can now handle constructors
  1784 with HOL function types.  Pattern-match combinators for the Pair
  1785 constructor are pre-configured.
  1786 
  1787 * The 'fixrec' package now produces better fixed-point induction rules
  1788 for mutually-recursive definitions:  Induction rules have conclusions
  1789 of the form "P foo bar" instead of "P <foo, bar>".
  1790 
  1791 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1792 been renamed to "below".  The name "below" now replaces "less" in many
  1793 theorem names.  (Legacy theorem names using "less" are still supported
  1794 as well.)
  1795 
  1796 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1797 patterns can be used to generate strictness rules, or to make
  1798 functions more strict (much like the bang-patterns supported by the
  1799 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1800 examples.
  1801 
  1802 
  1803 *** ML ***
  1804 
  1805 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1806 errors and run-time exceptions, including detailed source positions.
  1807 
  1808 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1809 identified entries, with some additional information such as source
  1810 position, logical grouping etc.
  1811 
  1812 * Theory and context data is now introduced by the simplified and
  1813 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1814 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1815 copy operation) is still available for some time.
  1816 
  1817 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1818 provides a high-level programming interface to synchronized state
  1819 variables with atomic update.  This works via pure function
  1820 application within a critical section -- its runtime should be as
  1821 short as possible; beware of deadlocks if critical code is nested,
  1822 either directly or indirectly via other synchronized variables!
  1823 
  1824 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1825 wraps raw ML references, explicitly indicating their non-thread-safe
  1826 behaviour.  The Isar toplevel keeps this structure open, to
  1827 accommodate Proof General as well as quick and dirty interactive
  1828 experiments with references.
  1829 
  1830 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1831 parallel tactical reasoning.
  1832 
  1833 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1834 are similar to SUBPROOF, but are slightly more flexible: only the
  1835 specified parts of the subgoal are imported into the context, and the
  1836 body tactic may introduce new subgoals and schematic variables.
  1837 
  1838 * Old tactical METAHYPS, which does not observe the proof context, has
  1839 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1840 or Subgoal.FOCUS etc.
  1841 
  1842 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  1843 functors have their own ML name space there is no point to mark them
  1844 separately.)  Minor INCOMPATIBILITY.
  1845 
  1846 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  1847 
  1848 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  1849 INCOMPATIBILITY.
  1850 
  1851 * Operations of structure Skip_Proof no longer require quick_and_dirty
  1852 mode, which avoids critical setmp.
  1853 
  1854 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  1855 combinators for "args".  INCOMPATIBILITY, need to use simplified
  1856 Attrib/Method.setup introduced in Isabelle2009.
  1857 
  1858 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  1859 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  1860 last resort.  INCOMPATIBILITY.
  1861 
  1862 * Display.pretty_thm now requires a proper context (cf. former
  1863 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  1864 or even Display.pretty_thm_without_context as last resort.
  1865 INCOMPATIBILITY.
  1866 
  1867 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  1868 Syntax.pretty_typ/term directly, preferably with proper context
  1869 instead of global theory.
  1870 
  1871 
  1872 *** System ***
  1873 
  1874 * Further fine tuning of parallel proof checking, scales up to 8 cores
  1875 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  1876 usedir option -q.
  1877 
  1878 * Support for additional "Isabelle components" via etc/components, see
  1879 also the system manual.
  1880 
  1881 * The isabelle makeall tool now operates on all components with
  1882 IsaMakefile, not just hardwired "logics".
  1883 
  1884 * Removed "compress" option from isabelle-process and isabelle usedir;
  1885 this is always enabled.
  1886 
  1887 * Discontinued support for Poly/ML 4.x versions.
  1888 
  1889 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  1890 on a given logic image.  This requires the lighttpd webserver and is
  1891 currently supported on Linux only.
  1892 
  1893 
  1894 
  1895 New in Isabelle2009 (April 2009)
  1896 --------------------------------
  1897 
  1898 *** General ***
  1899 
  1900 * Simplified main Isabelle executables, with less surprises on
  1901 case-insensitive file-systems (such as Mac OS).
  1902 
  1903   - The main Isabelle tool wrapper is now called "isabelle" instead of
  1904     "isatool."
  1905 
  1906   - The former "isabelle" alias for "isabelle-process" has been
  1907     removed (should rarely occur to regular users).
  1908 
  1909   - The former "isabelle-interface" and its alias "Isabelle" have been
  1910     removed (interfaces are now regular Isabelle tools).
  1911 
  1912 Within scripts and make files, the Isabelle environment variables
  1913 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  1914 respectively.  (The latter are still available as legacy feature.)
  1915 
  1916 The old isabelle-interface wrapper could react in confusing ways if
  1917 the interface was uninstalled or changed otherwise.  Individual
  1918 interface tool configuration is now more explicit, see also the
  1919 Isabelle system manual.  In particular, Proof General is now available
  1920 via "isabelle emacs".
  1921 
  1922 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  1923 purge installed copies of Isabelle executables and re-run "isabelle
  1924 install -p ...", or use symlinks.
  1925 
  1926 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  1927 old ~/isabelle, which was slightly non-standard and apt to cause
  1928 surprises on case-insensitive file-systems (such as Mac OS).
  1929 
  1930 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  1931 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  1932 care is required when using older releases of Isabelle.  Note that
  1933 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  1934 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  1935 
  1936 * Proofs of fully specified statements are run in parallel on
  1937 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  1938 a regular 4-core machine, if the initial heap space is made reasonably
  1939 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  1940 
  1941 * The main reference manuals ("isar-ref", "implementation", and
  1942 "system") have been updated and extended.  Formally checked references
  1943 as hyperlinks are now available uniformly.
  1944 
  1945 
  1946 *** Pure ***
  1947 
  1948 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  1949 respects.  The most important changes are listed below.  See the
  1950 Tutorial on Locales ("locales" manual) for details.
  1951 
  1952 - In locale expressions, instantiation replaces renaming.  Parameters
  1953 must be declared in a for clause.  To aid compatibility with previous
  1954 parameter inheritance, in locale declarations, parameters that are not
  1955 'touched' (instantiation position "_" or omitted) are implicitly added
  1956 with their syntax at the beginning of the for clause.
  1957 
  1958 - Syntax from abbreviations and definitions in locales is available in
  1959 locale expressions and context elements.  The latter is particularly
  1960 useful in locale declarations.
  1961 
  1962 - More flexible mechanisms to qualify names generated by locale
  1963 expressions.  Qualifiers (prefixes) may be specified in locale
  1964 expressions, and can be marked as mandatory (syntax: "name!:") or
  1965 optional (syntax "name?:").  The default depends for plain "name:"
  1966 depends on the situation where a locale expression is used: in
  1967 commands 'locale' and 'sublocale' prefixes are optional, in
  1968 'interpretation' and 'interpret' prefixes are mandatory.  The old
  1969 implicit qualifiers derived from the parameter names of a locale are
  1970 no longer generated.
  1971 
  1972 - Command "sublocale l < e" replaces "interpretation l < e".  The
  1973 instantiation clause in "interpretation" and "interpret" (square
  1974 brackets) is no longer available.  Use locale expressions.
  1975 
  1976 - When converting proof scripts, mandatory qualifiers in
  1977 'interpretation' and 'interpret' should be retained by default, even
  1978 if this is an INCOMPATIBILITY compared to former behavior.  In the
  1979 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  1980 in locale expressions range over a single locale instance only.
  1981 
  1982 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  1983 In existing theorem specifications replace the includes element by the
  1984 respective context elements of the included locale, omitting those
  1985 that are already present in the theorem specification.  Multiple
  1986 assume elements of a locale should be replaced by a single one
  1987 involving the locale predicate.  In the proof body, declarations (most
  1988 notably theorems) may be regained by interpreting the respective
  1989 locales in the proof context as required (command "interpret").
  1990 
  1991 If using "includes" in replacement of a target solely because the
  1992 parameter types in the theorem are not as general as in the target,
  1993 consider declaring a new locale with additional type constraints on
  1994 the parameters (context element "constrains").
  1995 
  1996 - Discontinued "locale (open)".  INCOMPATIBILITY.
  1997 
  1998 - Locale interpretation commands no longer attempt to simplify goal.
  1999 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  2000 methods intro_locales and unfold_locales to clarify.
  2001 
  2002 - Locale interpretation commands no longer accept interpretation
  2003 attributes.  INCOMPATIBILITY.
  2004 
  2005 * Class declaration: so-called "base sort" must not be given in import
  2006 list any longer, but is inferred from the specification.  Particularly
  2007 in HOL, write
  2008 
  2009     class foo = ...
  2010 
  2011 instead of
  2012 
  2013     class foo = type + ...
  2014 
  2015 * Class target: global versions of theorems stemming do not carry a
  2016 parameter prefix any longer.  INCOMPATIBILITY.
  2017 
  2018 * Class 'instance' command no longer accepts attached definitions.
  2019 INCOMPATIBILITY, use proper 'instantiation' target instead.
  2020 
  2021 * Recovered hiding of consts, which was accidentally broken in
  2022 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  2023 makes c inaccessible; consider using ``hide (open) const c'' instead.
  2024 
  2025 * Slightly more coherent Pure syntax, with updated documentation in
  2026 isar-ref manual.  Removed locales meta_term_syntax and
  2027 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  2028 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  2029 directly in regular applications.
  2030 
  2031 * There is a new syntactic category "float_const" for signed decimal
  2032 fractions (e.g. 123.45 or -123.45).
  2033 
  2034 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  2035 interface with 'setup' command instead.
  2036 
  2037 * Command 'local_setup' is similar to 'setup', but operates on a local
  2038 theory context.
  2039 
  2040 * The 'axiomatization' command now only works within a global theory
  2041 context.  INCOMPATIBILITY.
  2042 
  2043 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  2044 hypotheses.  Sorts required in the course of reasoning need to be
  2045 covered by the constraints in the initial statement, completed by the
  2046 type instance information of the background theory.  Non-trivial sort
  2047 hypotheses, which rarely occur in practice, may be specified via
  2048 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  2049 
  2050   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  2051 
  2052 The result contains an implicit sort hypotheses as before --
  2053 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  2054 normalization.
  2055 
  2056 * Generalized Isar history, with support for linear undo, direct state
  2057 addressing etc.
  2058 
  2059 * Changed defaults for unify configuration options:
  2060 
  2061   unify_trace_bound = 50 (formerly 25)
  2062   unify_search_bound = 60 (formerly 30)
  2063 
  2064 * Different bookkeeping for code equations (INCOMPATIBILITY):
  2065 
  2066   a) On theory merge, the last set of code equations for a particular
  2067      constant is taken (in accordance with the policy applied by other
  2068      parts of the code generator framework).
  2069 
  2070   b) Code equations stemming from explicit declarations (e.g. code
  2071      attribute) gain priority over default code equations stemming
  2072      from definition, primrec, fun etc.
  2073 
  2074 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  2075 
  2076 * Unified theorem tables for both code generators.  Thus [code
  2077 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  2078 
  2079 * Command 'find_consts' searches for constants based on type and name
  2080 patterns, e.g.
  2081 
  2082     find_consts "_ => bool"
  2083 
  2084 By default, matching is against subtypes, but it may be restricted to
  2085 the whole type.  Searching by name is possible.  Multiple queries are
  2086 conjunctive and queries may be negated by prefixing them with a
  2087 hyphen:
  2088 
  2089     find_consts strict: "_ => bool" name: "Int" -"int => int"
  2090 
  2091 * New 'find_theorems' criterion "solves" matches theorems that
  2092 directly solve the current goal (modulo higher-order unification).
  2093 
  2094 * Auto solve feature for main theorem statements: whenever a new goal
  2095 is stated, "find_theorems solves" is called; any theorems that could
  2096 solve the lemma directly are listed as part of the goal state.
  2097 Cf. associated options in Proof General Isabelle settings menu,
  2098 enabled by default, with reasonable timeout for pathological cases of
  2099 higher-order unification.
  2100 
  2101 
  2102 *** Document preparation ***
  2103 
  2104 * Antiquotation @{lemma} now imitates a regular terminal proof,
  2105 demanding keyword 'by' and supporting the full method expression
  2106 syntax just like the Isar command 'by'.
  2107 
  2108 
  2109 *** HOL ***
  2110 
  2111 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  2112 points Main and Complex_Main remain as before.
  2113 
  2114 * Logic image HOL-Plain provides a minimal HOL with the most important
  2115 tools available (inductive, datatype, primrec, ...).  This facilitates
  2116 experimentation and tool development.  Note that user applications
  2117 (and library theories) should never refer to anything below theory
  2118 Main, as before.
  2119 
  2120 * Logic image HOL-Main stops at theory Main, and thus facilitates
  2121 experimentation due to shorter build times.
  2122 
  2123 * Logic image HOL-NSA contains theories of nonstandard analysis which
  2124 were previously part of former HOL-Complex.  Entry point Hyperreal
  2125 remains valid, but theories formerly using Complex_Main should now use
  2126 new entry point Hypercomplex.
  2127 
  2128 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  2129 Posix processes.  Avoids potentially expensive forking of the ML
  2130 process.  New thread-based implementation also works on non-Unix
  2131 platforms (Cygwin).  Provers are no longer hardwired, but defined
  2132 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  2133 commands are covered in the isar-ref manual.
  2134 
  2135 * Wrapper scripts for remote SystemOnTPTP service allows to use
  2136 sledgehammer without local ATP installation (Vampire etc.). Other
  2137 provers may be included via suitable ML wrappers, see also
  2138 src/HOL/ATP_Linkup.thy.
  2139 
  2140 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  2141 menu.
  2142 
  2143 * The metis method no longer fails because the theorem is too trivial
  2144 (contains the empty clause).
  2145 
  2146 * The metis method now fails in the usual manner, rather than raising
  2147 an exception, if it determines that it cannot prove the theorem.
  2148 
  2149 * Method "coherent" implements a prover for coherent logic (see also
  2150 src/Tools/coherent.ML).
  2151 
  2152 * Constants "undefined" and "default" replace "arbitrary".  Usually
  2153 "undefined" is the right choice to replace "arbitrary", though
  2154 logically there is no difference.  INCOMPATIBILITY.
  2155 
  2156 * Command "value" now integrates different evaluation mechanisms.  The
  2157 result of the first successful evaluation mechanism is printed.  In
  2158 square brackets a particular named evaluation mechanisms may be
  2159 specified (currently, [SML], [code] or [nbe]).  See further
  2160 src/HOL/ex/Eval_Examples.thy.
  2161 
  2162 * Normalization by evaluation now allows non-leftlinear equations.
  2163 Declare with attribute [code nbe].
  2164 
  2165 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  2166 as the structured Isar versions "cases" and "induct", cf. the
  2167 corresponding "cases" and "induct" attributes.  Mutual induction rules
  2168 are now presented as a list of individual projections
  2169 (e.g. foo_bar.inducts for types foo and bar); the old format with
  2170 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  2171 rare situations a different rule is selected --- notably nested tuple
  2172 elimination instead of former prod.exhaust: use explicit (case_tac t
  2173 rule: prod.exhaust) here.
  2174 
  2175 * Attributes "cases", "induct", "coinduct" support "del" option.
  2176 
  2177 * Removed fact "case_split_thm", which duplicates "case_split".
  2178 
  2179 * The option datatype has been moved to a new theory Option.  Renamed
  2180 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  2181 
  2182 * New predicate "strict_mono" classifies strict functions on partial
  2183 orders.  With strict functions on linear orders, reasoning about
  2184 (in)equalities is facilitated by theorems "strict_mono_eq",
  2185 "strict_mono_less_eq" and "strict_mono_less".
  2186 
  2187 * Some set operations are now proper qualified constants with
  2188 authentic syntax.  INCOMPATIBILITY:
  2189 
  2190     op Int ~>   Set.Int
  2191     op Un ~>    Set.Un
  2192     INTER ~>    Set.INTER
  2193     UNION ~>    Set.UNION
  2194     Inter ~>    Set.Inter
  2195     Union ~>    Set.Union
  2196     {} ~>       Set.empty
  2197     UNIV ~>     Set.UNIV
  2198 
  2199 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  2200 theory Set.
  2201 
  2202 * Auxiliary class "itself" has disappeared -- classes without any
  2203 parameter are treated as expected by the 'class' command.
  2204 
  2205 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  2206 
  2207 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  2208 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  2209 
  2210 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  2211 method "approximation".  It proves formulas on real values by using
  2212 interval arithmetic.  In the formulas are also the transcendental
  2213 functions sin, cos, tan, atan, ln, exp and the constant pi are
  2214 allowed. For examples see
  2215 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  2216 
  2217 * Theory "Reflection" now resides in HOL/Library.
  2218 
  2219 * Entry point to Word library now simply named "Word".
  2220 INCOMPATIBILITY.
  2221 
  2222 * Made source layout more coherent with logical distribution
  2223 structure:
  2224 
  2225     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  2226     src/HOL/Library/Code_Message.thy ~> src/HOL/
  2227     src/HOL/Library/GCD.thy ~> src/HOL/
  2228     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  2229     src/HOL/Library/Parity.thy ~> src/HOL/
  2230     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  2231     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  2232     src/HOL/Real/Lubs.thy ~> src/HOL/
  2233     src/HOL/Real/PReal.thy ~> src/HOL/
  2234     src/HOL/Real/Rational.thy ~> src/HOL/
  2235     src/HOL/Real/RComplete.thy ~> src/HOL/
  2236     src/HOL/Real/RealDef.thy ~> src/HOL/
  2237     src/HOL/Real/RealPow.thy ~> src/HOL/
  2238     src/HOL/Real/Real.thy ~> src/HOL/
  2239     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  2240     src/HOL/Complex/Complex.thy ~> src/HOL/
  2241     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  2242     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  2243     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  2244     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  2245     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  2246     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  2247     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  2248     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  2249     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  2250     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  2251     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  2252     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  2253     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  2254     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  2255     src/HOL/Real/Float ~> src/HOL/Library/
  2256     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  2257     src/HOL/Real/RealVector.thy ~> src/HOL/
  2258 
  2259     src/HOL/arith_data.ML ~> src/HOL/Tools
  2260     src/HOL/hologic.ML ~> src/HOL/Tools
  2261     src/HOL/simpdata.ML ~> src/HOL/Tools
  2262     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  2263     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  2264     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  2265     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  2266     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  2267     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  2268     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  2269 
  2270     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  2271     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  2272     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  2273     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  2274     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  2275     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  2276 
  2277 * If methods "eval" and "evaluation" encounter a structured proof
  2278 state with !!/==>, only the conclusion is evaluated to True (if
  2279 possible), avoiding strange error messages.
  2280 
  2281 * Method "sizechange" automates termination proofs using (a
  2282 modification of) the size-change principle.  Requires SAT solver.  See
  2283 src/HOL/ex/Termination.thy for examples.
  2284 
  2285 * Simplifier: simproc for let expressions now unfolds if bound
  2286 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  2287 
  2288 * Method "arith": Linear arithmetic now ignores all inequalities when
  2289 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  2290 
  2291 * New attribute "arith" for facts that should always be used
  2292 automatically by arithmetic. It is intended to be used locally in
  2293 proofs, e.g.
  2294 
  2295   assumes [arith]: "x > 0"
  2296 
  2297 Global usage is discouraged because of possible performance impact.
  2298 
  2299 * New classes "top" and "bot" with corresponding operations "top" and
  2300 "bot" in theory Orderings; instantiation of class "complete_lattice"
  2301 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  2302 
  2303 * Changed definition lemma "less_fun_def" in order to provide an
  2304 instance for preorders on functions; use lemma "less_le" instead.
  2305 INCOMPATIBILITY.
  2306 
  2307 * Theory Orderings: class "wellorder" moved here, with explicit
  2308 induction rule "less_induct" as assumption.  For instantiation of
  2309 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  2310 INCOMPATIBILITY.
  2311 
  2312 * Theory Orderings: added class "preorder" as superclass of "order".
  2313 INCOMPATIBILITY: Instantiation proofs for order, linorder
  2314 etc. slightly changed.  Some theorems named order_class.* now named
  2315 preorder_class.*.
  2316 
  2317 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  2318 "diag" to "Id_on".
  2319 
  2320 * Theory Finite_Set: added a new fold combinator of type
  2321 
  2322   ('a => 'b => 'b) => 'b => 'a set => 'b
  2323 
  2324 Occasionally this is more convenient than the old fold combinator
  2325 which is now defined in terms of the new one and renamed to
  2326 fold_image.
  2327 
  2328 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  2329 and "ring_simps" have been replaced by "algebra_simps" (which can be
  2330 extended with further lemmas!).  At the moment both still exist but
  2331 the former will disappear at some point.
  2332 
  2333 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  2334 class recpower.  Type-specific simp rules for various recpower types
  2335 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  2336 
  2337 rat_power_0    -> power_0
  2338 rat_power_Suc  -> power_Suc
  2339 realpow_0      -> power_0
  2340 realpow_Suc    -> power_Suc
  2341 complexpow_0   -> power_0
  2342 complexpow_Suc -> power_Suc
  2343 power_poly_0   -> power_0
  2344 power_poly_Suc -> power_Suc
  2345 
  2346 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  2347 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  2348 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  2349 of lemmas from Divides has been generalized from nat to class
  2350 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  2351 renames resulting from duplicate elimination:
  2352 
  2353     dvd_def_mod ~>          dvd_eq_mod_eq_0
  2354     zero_dvd_iff ~>         dvd_0_left_iff
  2355     dvd_0 ~>                dvd_0_right
  2356     DIVISION_BY_ZERO_DIV ~> div_by_0
  2357     DIVISION_BY_ZERO_MOD ~> mod_by_0
  2358     mult_div ~>             div_mult_self2_is_id
  2359     mult_mod ~>             mod_mult_self2_is_0
  2360 
  2361 * Theory IntDiv: removed many lemmas that are instances of class-based
  2362 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  2363 rename old lemmas as follows:
  2364 
  2365 dvd_diff               -> nat_dvd_diff
  2366 dvd_zminus_iff         -> dvd_minus_iff
  2367 mod_add1_eq            -> mod_add_eq
  2368 mod_mult1_eq           -> mod_mult_right_eq
  2369 mod_mult1_eq'          -> mod_mult_left_eq
  2370 mod_mult_distrib_mod   -> mod_mult_eq
  2371 nat_mod_add_left_eq    -> mod_add_left_eq
  2372 nat_mod_add_right_eq   -> mod_add_right_eq
  2373 nat_mod_div_trivial    -> mod_div_trivial
  2374 nat_mod_mod_trivial    -> mod_mod_trivial
  2375 zdiv_zadd_self1        -> div_add_self1
  2376 zdiv_zadd_self2        -> div_add_self2
  2377 zdiv_zmult_self1       -> div_mult_self2_is_id
  2378 zdiv_zmult_self2       -> div_mult_self1_is_id
  2379 zdvd_triv_left         -> dvd_triv_left
  2380 zdvd_triv_right        -> dvd_triv_right
  2381 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  2382 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  2383 zmod_zadd_left_eq      -> mod_add_left_eq
  2384 zmod_zadd_right_eq     -> mod_add_right_eq
  2385 zmod_zadd_self1        -> mod_add_self1
  2386 zmod_zadd_self2        -> mod_add_self2
  2387 zmod_zadd1_eq          -> mod_add_eq
  2388 zmod_zdiff1_eq         -> mod_diff_eq
  2389 zmod_zdvd_zmod         -> mod_mod_cancel
  2390 zmod_zmod_cancel       -> mod_mod_cancel
  2391 zmod_zmult_self1       -> mod_mult_self2_is_0
  2392 zmod_zmult_self2       -> mod_mult_self1_is_0
  2393 zmod_1                 -> mod_by_1
  2394 zdiv_1                 -> div_by_1
  2395 zdvd_abs1              -> abs_dvd_iff
  2396 zdvd_abs2              -> dvd_abs_iff
  2397 zdvd_refl              -> dvd_refl
  2398 zdvd_trans             -> dvd_trans
  2399 zdvd_zadd              -> dvd_add
  2400 zdvd_zdiff             -> dvd_diff
  2401 zdvd_zminus_iff        -> dvd_minus_iff
  2402 zdvd_zminus2_iff       -> minus_dvd_iff
  2403 zdvd_zmultD            -> dvd_mult_right
  2404 zdvd_zmultD2           -> dvd_mult_left
  2405 zdvd_zmult_mono        -> mult_dvd_mono
  2406 zdvd_0_right           -> dvd_0_right
  2407 zdvd_0_left            -> dvd_0_left_iff
  2408 zdvd_1_left            -> one_dvd
  2409 zminus_dvd_iff         -> minus_dvd_iff
  2410 
  2411 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  2412 
  2413 * The real numbers offer decimal input syntax: 12.34 is translated
  2414 into 1234/10^2. This translation is not reversed upon output.
  2415 
  2416 * Theory Library/Polynomial defines an abstract type 'a poly of
  2417 univariate polynomials with coefficients of type 'a.  In addition to
  2418 the standard ring operations, it also supports div and mod.  Code
  2419 generation is also supported, using list-style constructors.
  2420 
  2421 * Theory Library/Inner_Product defines a class of real_inner for real
  2422 inner product spaces, with an overloaded operation inner :: 'a => 'a
  2423 => real.  Class real_inner is a subclass of real_normed_vector from
  2424 theory RealVector.
  2425 
  2426 * Theory Library/Product_Vector provides instances for the product
  2427 type 'a * 'b of several classes from RealVector and Inner_Product.
  2428 Definitions of addition, subtraction, scalar multiplication, norms,
  2429 and inner products are included.
  2430 
  2431 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  2432 addition to the field operations, numerals and case syntax are also
  2433 supported.
  2434 
  2435 * Theory Library/Diagonalize provides constructive version of Cantor's
  2436 first diagonalization argument.
  2437 
  2438 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  2439 zlcm (for int); carried together from various gcd/lcm developements in
  2440 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  2441 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  2442 may recover tupled syntax as follows:
  2443 
  2444     hide (open) const gcd
  2445     abbreviation gcd where
  2446       "gcd == (%(a, b). GCD.gcd a b)"
  2447     notation (output)
  2448       GCD.gcd ("gcd '(_, _')")
  2449 
  2450 The same works for lcm, zgcd, zlcm.
  2451 
  2452 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  2453 instantiations for algebraic structures.  Removed some duplicate
  2454 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  2455 
  2456 * ML antiquotation @{code} takes a constant as argument and generates
  2457 corresponding code in background and inserts name of the corresponding
  2458 resulting ML value/function/datatype constructor binding in place.
  2459 All occurrences of @{code} with a single ML block are generated
  2460 simultaneously.  Provides a generic and safe interface for
  2461 instrumentalizing code generation.  See
  2462 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  2463 In future you ought to refrain from ad-hoc compiling generated SML
  2464 code on the ML toplevel.  Note that (for technical reasons) @{code}
  2465 cannot refer to constants for which user-defined serializations are
  2466 set.  Refer to the corresponding ML counterpart directly in that
  2467 cases.
  2468 
  2469 * Command 'rep_datatype': instead of theorem names the command now
  2470 takes a list of terms denoting the constructors of the type to be
  2471 represented as datatype.  The characteristic theorems have to be
  2472 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  2473 have disappeared in favour of existing ones:
  2474 
  2475     unit_induct                 ~> unit.induct
  2476     prod_induct                 ~> prod.induct
  2477     sum_induct                  ~> sum.induct
  2478     Suc_Suc_eq                  ~> nat.inject
  2479     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  2480 
  2481 
  2482 *** HOL-Algebra ***
  2483 
  2484 * New locales for orders and lattices where the equivalence relation
  2485 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  2486 locales use a record structure with field eq for the equivalence.
  2487 
  2488 * New theory of factorial domains.
  2489 
  2490 * Units_l_inv and Units_r_inv are now simp rules by default.
  2491 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  2492 and/or r_inv will now also require deletion of these lemmas.
  2493 
  2494 * Renamed the following theorems, INCOMPATIBILITY:
  2495 
  2496 UpperD ~> Upper_memD
  2497 LowerD ~> Lower_memD
  2498 least_carrier ~> least_closed
  2499 greatest_carrier ~> greatest_closed
  2500 greatest_Lower_above ~> greatest_Lower_below
  2501 one_zero ~> carrier_one_zero
  2502 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  2503 
  2504 
  2505 *** HOL-Nominal ***
  2506 
  2507 * Nominal datatypes can now contain type-variables.
  2508 
  2509 * Commands 'nominal_inductive' and 'equivariance' work with local
  2510 theory targets.
  2511 
  2512 * Nominal primrec can now works with local theory targets and its
  2513 specification syntax now conforms to the general format as seen in
  2514 'inductive' etc.
  2515 
  2516 * Method "perm_simp" honours the standard simplifier attributes
  2517 (no_asm), (no_asm_use) etc.
  2518 
  2519 * The new predicate #* is defined like freshness, except that on the
  2520 left hand side can be a set or list of atoms.
  2521 
  2522 * Experimental command 'nominal_inductive2' derives strong induction
  2523 principles for inductive definitions.  In contrast to
  2524 'nominal_inductive', which can only deal with a fixed number of
  2525 binders, it can deal with arbitrary expressions standing for sets of
  2526 atoms to be avoided.  The only inductive definition we have at the
  2527 moment that needs this generalisation is the typing rule for Lets in
  2528 the algorithm W:
  2529 
  2530  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  2531  -----------------------------------------------------------------
  2532          Gamma |- Let x be t1 in t2 : T2
  2533 
  2534 In this rule one wants to avoid all the binders that are introduced by
  2535 "close Gamma T1".  We are looking for other examples where this
  2536 feature might be useful.  Please let us know.
  2537 
  2538 
  2539 *** HOLCF ***
  2540 
  2541 * Reimplemented the simplification procedure for proving continuity
  2542 subgoals.  The new simproc is extensible; users can declare additional
  2543 continuity introduction rules with the attribute [cont2cont].
  2544 
  2545 * The continuity simproc now uses a different introduction rule for
  2546 solving continuity subgoals on terms with lambda abstractions.  In
  2547 some rare cases the new simproc may fail to solve subgoals that the
  2548 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  2549 Potential INCOMPATIBILITY.
  2550 
  2551 * Command 'fixrec': specification syntax now conforms to the general
  2552 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  2553 examples.  INCOMPATIBILITY.
  2554 
  2555 
  2556 *** ZF ***
  2557 
  2558 * Proof of Zorn's Lemma for partial orders.
  2559 
  2560 
  2561 *** ML ***
  2562 
  2563 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  2564 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  2565 depends on multithreading, so timouts will not work before Poly/ML
  2566 5.2.1!
  2567 
  2568 * High-level support for concurrent ML programming, see
  2569 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  2570 particularly convenient to organize independent functional
  2571 computations.  The concept of "synchronized variables" provides a
  2572 higher-order interface for components with shared state, avoiding the
  2573 delicate details of mutexes and condition variables.  (Requires
  2574 Poly/ML 5.2.1 or later.)
  2575 
  2576 * ML bindings produced via Isar commands are stored within the Isar
  2577 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2578 become thread-safe and work with undo as expected (concerning
  2579 top-level bindings, not side-effects on global references).
  2580 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2581 compiler at runtime; really global bindings need to be given outside a
  2582 theory.  (Requires Poly/ML 5.2 or later.)
  2583 
  2584 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2585 context.  Top-level ML bindings are stored within the proof context in
  2586 a purely sequential fashion, disregarding the nested proof structure.
  2587 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2588 proof.  (Requires Poly/ML 5.2 or later.)
  2589 
  2590 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2591 and Method.setup, as well as Isar commands 'attribute_setup' and
  2592 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2593 existing code accordingly, or use plain 'setup' together with old
  2594 Method.add_method.
  2595 
  2596 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2597 to 'a -> thm, while results are always tagged with an authentic oracle
  2598 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2599 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2600 accordingly.  Note that extra performance may be gained by producing
  2601 the cterm carefully, avoiding slow Thm.cterm_of.
  2602 
  2603 * Simplified interface for defining document antiquotations via
  2604 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2605 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2606 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2607 examples.
  2608 
  2609 * More systematic treatment of long names, abstract name bindings, and
  2610 name space operations.  Basic operations on qualified names have been
  2611 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2612 Long_Name.append.  Old type bstring has been mostly replaced by
  2613 abstract type binding (see structure Binding), which supports precise
  2614 qualification by packages and local theory targets, as well as proper
  2615 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2616 bstring values into Binding.name, or better pass through abstract
  2617 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2618 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2619 
  2620 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2621 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2622 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2623 
  2624 * Disposed old type and term read functions (Sign.read_def_typ,
  2625 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2626 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2627 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2628 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2629 resort for legacy applications.
  2630 
  2631 * Disposed old declarations, tactics, tactic combinators that refer to
  2632 the simpset or claset of an implicit theory (such as Addsimps,
  2633 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2634 embedded ML text, or local_simpset_of with a proper context passed as
  2635 explicit runtime argument.
  2636 
  2637 * Rules and tactics that read instantiations (read_instantiate,
  2638 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2639 context, which is required for parsing and type-checking.  Moreover,
  2640 the variables are specified as plain indexnames, not string encodings
  2641 thereof.  INCOMPATIBILITY.
  2642 
  2643 * Generic Toplevel.add_hook interface allows to analyze the result of
  2644 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2645 for theorem dependency output of transactions resulting in a new
  2646 theory state.
  2647 
  2648 * ML antiquotations: block-structured compilation context indicated by
  2649 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2650 
  2651   @{binding name}                         - basic name binding
  2652   @{let ?pat = term}                      - term abbreviation (HO matching)
  2653   @{note name = fact}                     - fact abbreviation
  2654   @{thm fact}                             - singleton fact (with attributes)
  2655   @{thms fact}                            - general fact (with attributes)
  2656   @{lemma prop by method}                 - singleton goal
  2657   @{lemma prop by meth1 meth2}            - singleton goal
  2658   @{lemma prop1 ... propN by method}      - general goal
  2659   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2660   @{lemma (open) ...}                     - open derivation
  2661 
  2662 
  2663 *** System ***
  2664 
  2665 * The Isabelle "emacs" tool provides a specific interface to invoke
  2666 Proof General / Emacs, with more explicit failure if that is not
  2667 installed (the old isabelle-interface script silently falls back on
  2668 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2669 installation location of the Proof General distribution.
  2670 
  2671 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2672 the Isabelle process into a JVM/Scala application.  See
  2673 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2674 process wrapper has been discontinued.)
  2675 
  2676 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2677 
  2678 * Various status messages (with exact source position information) are
  2679 emitted, if proper markup print mode is enabled.  This allows
  2680 user-interface components to provide detailed feedback on internal
  2681 prover operations.
  2682 
  2683 
  2684 
  2685 New in Isabelle2008 (June 2008)
  2686 -------------------------------
  2687 
  2688 *** General ***
  2689 
  2690 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2691 and updated, with formally checked references as hyperlinks.
  2692 
  2693 * Theory loader: use_thy (and similar operations) no longer set the
  2694 implicit ML context, which was occasionally hard to predict and in
  2695 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2696 provides a proper context already.
  2697 
  2698 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2699 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2700 'use' within a theory file will do the job.
  2701 
  2702 * Name space merge now observes canonical order, i.e. the second space
  2703 is inserted into the first one, while existing entries in the first
  2704 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2705 swap theory imports.
  2706 
  2707 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2708 INCOMPATIBILITY in identifier syntax etc.
  2709 
  2710 * Outer syntax: string tokens no longer admit escaped white space,
  2711 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2712 white space without escapes.
  2713 
  2714 * Outer syntax: string tokens may contain arbitrary character codes
  2715 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2716 "foo_bar".
  2717 
  2718 
  2719 *** Pure ***
  2720 
  2721 * Context-dependent token translations.  Default setup reverts locally
  2722 fixed variables, and adds hilite markup for undeclared frees.
  2723 
  2724 * Unused theorems can be found using the new command 'unused_thms'.
  2725 There are three ways of invoking it:
  2726 
  2727 (1) unused_thms
  2728      Only finds unused theorems in the current theory.
  2729 
  2730 (2) unused_thms thy_1 ... thy_n -
  2731      Finds unused theorems in the current theory and all of its ancestors,
  2732      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2733 
  2734 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2735      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2736      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2737      their ancestors.
  2738 
  2739 In order to increase the readability of the list produced by
  2740 unused_thms, theorems that have been created by a particular instance
  2741 of a theory command such as 'inductive' or 'function' are considered
  2742 to belong to the same "group", meaning that if at least one theorem in
  2743 this group is used, the other theorems in the same group are no longer
  2744 reported as unused.  Moreover, if all theorems in the group are
  2745 unused, only one theorem in the group is displayed.
  2746 
  2747 Note that proof objects have to be switched on in order for
  2748 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2749 usually the case when using Proof General with the default settings).
  2750 
  2751 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2752 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2753 duplicate fact bindings, or even accidental fact duplications.  Note
  2754 that tools may maintain dynamically scoped facts systematically, using
  2755 PureThy.add_thms_dynamic.
  2756 
  2757 * Command 'hide' now allows to hide from "fact" name space as well.
  2758 
  2759 * Eliminated destructive theorem database, simpset, claset, and
  2760 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2761 update of theories within ML code.
  2762 
  2763 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2764 INCOMPATIBILITY, object-logics depending on former Pure require
  2765 additional setup PureThy.old_appl_syntax_setup; object-logics
  2766 depending on former CPure need to refer to Pure.
  2767 
  2768 * Commands 'use' and 'ML' are now purely functional, operating on
  2769 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2770 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2771 INCOMPATIBILITY.
  2772 
  2773 * Command 'setup': discontinued implicit version with ML reference.
  2774 
  2775 * Instantiation target allows for simultaneous specification of class
  2776 instance operations together with an instantiation proof.
  2777 Type-checking phase allows to refer to class operations uniformly.
  2778 See src/HOL/Complex/Complex.thy for an Isar example and
  2779 src/HOL/Library/Eval.thy for an ML example.
  2780 
  2781 * Indexing of literal facts: be more serious about including only
  2782 facts from the visible specification/proof context, but not the
  2783 background context (locale etc.).  Affects `prop` notation and method
  2784 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2785 situations.
  2786 
  2787 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2788 "(open)" option, which used to expose internal bound variables to the
  2789 proof text.
  2790 
  2791 * Isar statements: removed obsolete case "rule_context".
  2792 INCOMPATIBILITY, better use explicit fixes/assumes.
  2793 
  2794 * Locale proofs: default proof step now includes 'unfold_locales';
  2795 hence 'proof' without argument may be used to unfold locale
  2796 predicates.
  2797 
  2798 
  2799 *** Document preparation ***
  2800 
  2801 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2802 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2803 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2804 spot); renamed link color from "darkblue" to "linkcolor" (default
  2805 value unchanged, can be redefined via \definecolor); no longer sets
  2806 "a4paper" option (unnecessary or even intrusive).
  2807 
  2808 * Antiquotation @{lemma A method} proves proposition A by the given
  2809 method (either a method name or a method name plus (optional) method
  2810 arguments in parentheses) and prints A just like @{prop A}.
  2811 
  2812 
  2813 *** HOL ***
  2814 
  2815 * New primrec package.  Specification syntax conforms in style to
  2816 definition/function/....  No separate induction rule is provided.  The
  2817 "primrec" command distinguishes old-style and new-style specifications
  2818 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2819 When adjusting theories, beware: constants stemming from new-style
  2820 primrec specifications have authentic syntax.
  2821 
  2822 * Metis prover is now an order of magnitude faster, and also works
  2823 with multithreading.
  2824 
  2825 * Metis: the maximum number of clauses that can be produced from a
  2826 theorem is now given by the attribute max_clauses.  Theorems that
  2827 exceed this number are ignored, with a warning printed.
  2828 
  2829 * Sledgehammer no longer produces structured proofs by default. To
  2830 enable, declare [[sledgehammer_full = true]].  Attributes
  2831 reconstruction_modulus, reconstruction_sorts renamed
  2832 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2833 
  2834 * Method "induct_scheme" derives user-specified induction rules
  2835 from well-founded induction and completeness of patterns. This factors
  2836 out some operations that are done internally by the function package
  2837 and makes them available separately.  See
  2838 src/HOL/ex/Induction_Scheme.thy for examples.
  2839 
  2840 * More flexible generation of measure functions for termination
  2841 proofs: Measure functions can be declared by proving a rule of the
  2842 form "is_measure f" and giving it the [measure_function] attribute.
  2843 The "is_measure" predicate is logically meaningless (always true), and
  2844 just guides the heuristic.  To find suitable measure functions, the
  2845 termination prover sets up the goal "is_measure ?f" of the appropriate
  2846 type and generates all solutions by prolog-style backwards proof using
  2847 the declared rules.
  2848 
  2849 This setup also deals with rules like 
  2850 
  2851   "is_measure f ==> is_measure (list_size f)"
  2852 
  2853 which accommodates nested datatypes that recurse through lists.
  2854 Similar rules are predeclared for products and option types.
  2855 
  2856 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  2857 
  2858   INCOMPATIBILITIES:
  2859 
  2860   - Definitions of overloaded constants on sets have to be replaced by
  2861     definitions on => and bool.
  2862 
  2863   - Some definitions of overloaded operators on sets can now be proved
  2864     using the definitions of the operators on => and bool.  Therefore,
  2865     the following theorems have been renamed:
  2866 
  2867       subset_def   -> subset_eq
  2868       psubset_def  -> psubset_eq
  2869       set_diff_def -> set_diff_eq
  2870       Compl_def    -> Compl_eq
  2871       Sup_set_def  -> Sup_set_eq
  2872       Inf_set_def  -> Inf_set_eq
  2873       sup_set_def  -> sup_set_eq
  2874       inf_set_def  -> inf_set_eq
  2875 
  2876   - Due to the incompleteness of the HO unification algorithm, some
  2877     rules such as subst may require manual instantiation, if some of
  2878     the unknowns in the rule is a set.
  2879 
  2880   - Higher order unification and forward proofs:
  2881     The proof pattern
  2882 
  2883       have "P (S::'a set)" <...>
  2884       then have "EX S. P S" ..
  2885 
  2886     no longer works (due to the incompleteness of the HO unification
  2887     algorithm) and must be replaced by the pattern
  2888 
  2889       have "EX S. P S"
  2890       proof
  2891         show "P S" <...>
  2892       qed
  2893 
  2894   - Calculational reasoning with subst (or similar rules):
  2895     The proof pattern
  2896 
  2897       have "P (S::'a set)" <...>
  2898       also have "S = T" <...>
  2899       finally have "P T" .
  2900 
  2901     no longer works (for similar reasons as the previous example) and
  2902     must be replaced by something like
  2903 
  2904       have "P (S::'a set)" <...>
  2905       moreover have "S = T" <...>
  2906       ultimately have "P T" by simp
  2907 
  2908   - Tactics or packages written in ML code:
  2909     Code performing pattern matching on types via
  2910 
  2911       Type ("set", [T]) => ...
  2912 
  2913     must be rewritten. Moreover, functions like strip_type or
  2914     binder_types no longer return the right value when applied to a
  2915     type of the form
  2916 
  2917       T1 => ... => Tn => U => bool
  2918 
  2919     rather than
  2920 
  2921       T1 => ... => Tn => U set
  2922 
  2923 * Merged theories Wellfounded_Recursion, Accessible_Part and
  2924 Wellfounded_Relations to theory Wellfounded.
  2925 
  2926 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  2927 
  2928 * Class finite no longer treats UNIV as class parameter.  Use class
  2929 enum from theory Library/Enum instead to achieve a similar effect.
  2930 INCOMPATIBILITY.
  2931 
  2932 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  2933 and "Cons".  INCOMPATIBILITY.
  2934 
  2935 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  2936 Potential INCOMPATIBILITY.
  2937 
  2938 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  2939 injective_fst_snd removed, use split_eta and prod_eqI instead.
  2940 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  2941 
  2942 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  2943 the same name in theory Orderings:
  2944 
  2945   less_trans
  2946   less_linear
  2947   le_imp_less_or_eq
  2948   le_less_trans
  2949   less_le_trans
  2950   less_not_sym
  2951   less_asym
  2952 
  2953 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  2954 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  2955 and different variable names.
  2956 
  2957 * Library/Option_ord.thy: Canonical order on option type.
  2958 
  2959 * Library/RBT.thy: Red-black trees, an efficient implementation of
  2960 finite maps.
  2961 
  2962 * Library/Countable.thy: Type class for countable types.
  2963 
  2964 * Theory Int: The representation of numerals has changed.  The infix
  2965 operator BIT and the bit datatype with constructors B0 and B1 have
  2966 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  2967 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  2968 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  2969 accordingly.
  2970 
  2971 * Theory Nat: definition of <= and < on natural numbers no longer
  2972 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  2973 le_def and less_def have disappeared.  Consider lemmas not_less
  2974 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  2975 
  2976 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  2977 (whose purpose mainly is for various fold_set functionals) have been
  2978 abandoned in favor of the existing algebraic classes
  2979 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  2980 lower_semilattice (resp. upper_semilattice) and linorder.
  2981 INCOMPATIBILITY.
  2982 
  2983 * Theory Transitive_Closure: induct and cases rules now declare proper
  2984 case_names ("base" and "step").  INCOMPATIBILITY.
  2985 
  2986 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  2987 lattices.  The form set-specific version is available as
  2988 Inductive.lfp_ordinal_induct_set.
  2989 
  2990 * Renamed theorems "power.simps" to "power_int.simps".
  2991 INCOMPATIBILITY.
  2992 
  2993 * Class semiring_div provides basic abstract properties of semirings
  2994 with division and modulo operations.  Subsumes former class dvd_mod.
  2995 
  2996 * Merged theories IntDef, Numeral and IntArith into unified theory
  2997 Int.  INCOMPATIBILITY.
  2998 
  2999 * Theory Library/Code_Index: type "index" now represents natural
  3000 numbers rather than integers.  INCOMPATIBILITY.
  3001 
  3002 * New class "uminus" with operation "uminus" (split of from class
  3003 "minus" which now only has operation "minus", binary).
  3004 INCOMPATIBILITY.
  3005 
  3006 * Constants "card", "internal_split", "option_map" now with authentic
  3007 syntax.  INCOMPATIBILITY.
  3008 
  3009 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  3010 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  3011 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  3012 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  3013 Sup_set_def, le_def, less_def, option_map_def now with object
  3014 equality.  INCOMPATIBILITY.
  3015 
  3016 * Records. Removed K_record, and replaced it by pure lambda term
  3017 %x. c. The simplifier setup is now more robust against eta expansion.
  3018 INCOMPATIBILITY: in cases explicitly referring to K_record.
  3019 
  3020 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  3021 
  3022 * Library/ListVector: new theory of arithmetic vector operations.
  3023 
  3024 * Library/Order_Relation: new theory of various orderings as sets of
  3025 pairs.  Defines preorders, partial orders, linear orders and
  3026 well-orders on sets and on types.
  3027 
  3028 
  3029 *** ZF ***
  3030 
  3031 * Renamed some theories to allow to loading both ZF and HOL in the
  3032 same session:
  3033 
  3034   Datatype  -> Datatype_ZF
  3035   Inductive -> Inductive_ZF
  3036   Int       -> Int_ZF
  3037   IntDiv    -> IntDiv_ZF
  3038   Nat       -> Nat_ZF
  3039   List      -> List_ZF
  3040   Main      -> Main_ZF
  3041 
  3042 INCOMPATIBILITY: ZF theories that import individual theories below
  3043 Main might need to be adapted.  Regular theory Main is still
  3044 available, as trivial extension of Main_ZF.
  3045 
  3046 
  3047 *** ML ***
  3048 
  3049 * ML within Isar: antiquotation @{const name} or @{const
  3050 name(typargs)} produces statically-checked Const term.
  3051 
  3052 * Functor NamedThmsFun: data is available to the user as dynamic fact
  3053 (of the same name).  Removed obsolete print command.
  3054 
  3055 * Removed obsolete "use_legacy_bindings" function.
  3056 
  3057 * The ``print mode'' is now a thread-local value derived from a global
  3058 template (the former print_mode reference), thus access becomes
  3059 non-critical.  The global print_mode reference is for session
  3060 management only; user-code should use print_mode_value,
  3061 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  3062 
  3063 * Functions system/system_out provide a robust way to invoke external
  3064 shell commands, with propagation of interrupts (requires Poly/ML
  3065 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  3066 
  3067 
  3068 *** System ***
  3069 
  3070 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  3071 in accordance with Proof General 3.7, which prefers GNU emacs.
  3072 
  3073 * isatool tty runs Isabelle process with plain tty interaction;
  3074 optional line editor may be specified via ISABELLE_LINE_EDITOR
  3075 setting, the default settings attempt to locate "ledit" and "rlwrap".
  3076 
  3077 * isatool browser now works with Cygwin as well, using general
  3078 "javapath" function defined in Isabelle process environment.
  3079 
  3080 * YXML notation provides a simple and efficient alternative to
  3081 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  3082 isatool yxml as described in the Isabelle system manual.
  3083 
  3084 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  3085 provides general wrapper for managing an Isabelle process in a robust
  3086 fashion, with ``cooked'' output from stdin/stderr.
  3087 
  3088 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  3089 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  3090 
  3091 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  3092 way of changing the user's settings is via
  3093 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  3094 script.
  3095 
  3096 * Multithreading.max_threads := 0 refers to the number of actual CPU
  3097 cores of the underlying machine, which is a good starting point for
  3098 optimal performance tuning.  The corresponding usedir option -M allows
  3099 "max" as an alias for "0".  WARNING: does not work on certain versions
  3100 of Mac OS (with Poly/ML 5.1).
  3101 
  3102 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  3103 adverse effect of Isabelle flooding interactive front-ends (notably
  3104 ProofGeneral / XEmacs).
  3105 
  3106 
  3107 
  3108 New in Isabelle2007 (November 2007)
  3109 -----------------------------------
  3110 
  3111 *** General ***
  3112 
  3113 * More uniform information about legacy features, notably a
  3114 warning/error of "Legacy feature: ...", depending on the state of the
  3115 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  3116 legacy features will disappear eventually.
  3117 
  3118 * Theory syntax: the header format ``theory A = B + C:'' has been
  3119 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  3120 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  3121 
  3122 * Theory syntax: the old non-Isar theory file format has been
  3123 discontinued altogether.  Note that ML proof scripts may still be used
  3124 with Isar theories; migration is usually quite simple with the ML
  3125 function use_legacy_bindings.  INCOMPATIBILITY.
  3126 
  3127 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  3128 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  3129 quotes.
  3130 
  3131 * Theory loader: be more serious about observing the static theory
  3132 header specifications (including optional directories), but not the
  3133 accidental file locations of previously successful loads.  The strict
  3134 update policy of former update_thy is now already performed by
  3135 use_thy, so the former has been removed; use_thys updates several
  3136 theories simultaneously, just as 'imports' within a theory header
  3137 specification, but without merging the results.  Potential
  3138 INCOMPATIBILITY: may need to refine theory headers and commands
  3139 ROOT.ML which depend on load order.
  3140 
  3141 * Theory loader: optional support for content-based file
  3142 identification, instead of the traditional scheme of full physical
  3143 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  3144 (cf. the system manual).  The new scheme allows to work with
  3145 non-finished theories in persistent session images, such that source
  3146 files may be moved later on without requiring reloads.
  3147 
  3148 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3149 file (with the same base name as the theory) are considered a legacy
  3150 feature, which will disappear eventually. Even now, the theory loader
  3151 no longer maintains dependencies on such files.
  3152 
  3153 * Syntax: the scope for resolving ambiguities via type-inference is
  3154 now limited to individual terms, instead of whole simultaneous
  3155 specifications as before. This greatly reduces the complexity of the
  3156 syntax module and improves flexibility by separating parsing and
  3157 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  3158 'fixes' etc.) are required in rare situations.
  3159 
  3160 * Syntax: constants introduced by new-style packages ('definition',
  3161 'abbreviation' etc.) are passed through the syntax module in
  3162 ``authentic mode''. This means that associated mixfix annotations
  3163 really stick to such constants, independently of potential name space
  3164 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  3165 trees are represented slightly differently, may need to adapt syntax
  3166 translations accordingly. Use CONST marker in 'translations' and
  3167 @{const_syntax} antiquotation in 'parse_translation' etc.
  3168 
  3169 * Legacy goal package: reduced interface to the bare minimum required
  3170 to keep existing proof scripts running.  Most other user-level
  3171 functions are now part of the OldGoals structure, which is *not* open
  3172 by default (consider isatool expandshort before open OldGoals).
  3173 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  3174 these tend to cause confusion about the actual goal (!) context being
  3175 used here, which is not necessarily the same as the_context().
  3176 
  3177 * Command 'find_theorems': supports "*" wild-card in "name:"
  3178 criterion; "with_dups" option.  Certain ProofGeneral versions might
  3179 support a specific search form (see ProofGeneral/CHANGES).
  3180 
  3181 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  3182 by default, which means that "prems" (and also "fixed variables") are
  3183 suppressed from proof state output.  Note that the ProofGeneral
  3184 settings mechanism allows to change and save options persistently, but
  3185 older versions of Isabelle will fail to start up if a negative prems
  3186 limit is imposed.
  3187 
  3188 * Local theory targets may be specified by non-nested blocks of
  3189 ``context/locale/class ... begin'' followed by ``end''.  The body may
  3190 contain definitions, theorems etc., including any derived mechanism
  3191 that has been implemented on top of these primitives.  This concept
  3192 generalizes the existing ``theorem (in ...)'' towards more versatility
  3193 and scalability.
  3194 
  3195 * Proof General interface: proper undo of final 'end' command;
  3196 discontinued Isabelle/classic mode (ML proof scripts).
  3197 
  3198 
  3199 *** Document preparation ***
  3200 
  3201 * Added antiquotation @{theory name} which prints the given name,
  3202 after checking that it refers to a valid ancestor theory in the
  3203 current context.
  3204 
  3205 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  3206 check the given source text as ML type/structure, printing verbatim.
  3207 
  3208 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  3209 "c args == rhs" given in the current context.  (Any number of
  3210 arguments may be given on the LHS.)
  3211 
  3212 
  3213 *** Pure ***
  3214 
  3215 * The 'class' package offers a combination of axclass and locale to
  3216 achieve Haskell-like type classes in Isabelle.  Definitions and
  3217 theorems within a class context produce both relative results (with
  3218 implicit parameters according to the locale context), and polymorphic
  3219 constants with qualified polymorphism (according to the class
  3220 context).  Within the body context of a 'class' target, a separate
  3221 syntax layer ("user space type system") takes care of converting
  3222 between global polymorphic consts and internal locale representation.
  3223 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  3224 "isatool doc classes" provides a tutorial.
  3225 
  3226 * Generic code generator framework allows to generate executable
  3227 code for ML and Haskell (including Isabelle classes).  A short usage
  3228 sketch:
  3229 
  3230     internal compilation:
  3231         export_code <list of constants (term syntax)> in SML
  3232     writing SML code to a file:
  3233         export_code <list of constants (term syntax)> in SML <filename>
  3234     writing OCaml code to a file:
  3235         export_code <list of constants (term syntax)> in OCaml <filename>
  3236     writing Haskell code to a bunch of files:
  3237         export_code <list of constants (term syntax)> in Haskell <filename>
  3238 
  3239     evaluating closed propositions to True/False using code generation:
  3240         method ``eval''
  3241 
  3242 Reasonable default setup of framework in HOL.
  3243 
  3244 Theorem attributs for selecting and transforming function equations theorems:
  3245 
  3246     [code fun]:        select a theorem as function equation for a specific constant
  3247     [code fun del]:    deselect a theorem as function equation for a specific constant
  3248     [code inline]:     select an equation theorem for unfolding (inlining) in place
  3249     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  3250 
  3251 User-defined serializations (target in {SML, OCaml, Haskell}):
  3252 
  3253     code_const <and-list of constants (term syntax)>
  3254       {(target) <and-list of const target syntax>}+
  3255 
  3256     code_type <and-list of type constructors>
  3257       {(target) <and-list of type target syntax>}+
  3258 
  3259     code_instance <and-list of instances>
  3260       {(target)}+
  3261         where instance ::= <type constructor> :: <class>
  3262 
  3263     code_class <and_list of classes>
  3264       {(target) <and-list of class target syntax>}+
  3265         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  3266 
  3267 code_instance and code_class only are effective to target Haskell.
  3268 
  3269 For example usage see src/HOL/ex/Codegenerator.thy and
  3270 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  3271 generation from Isabelle/HOL theories is available via "isatool doc
  3272 codegen".
  3273 
  3274 * Code generator: consts in 'consts_code' Isar commands are now
  3275 referred to by usual term syntax (including optional type
  3276 annotations).
  3277 
  3278 * Command 'no_translations' removes translation rules from theory
  3279 syntax.
  3280 
  3281 * Overloaded definitions are now actually checked for acyclic
  3282 dependencies.  The overloading scheme is slightly more general than
  3283 that of Haskell98, although Isabelle does not demand an exact
  3284 correspondence to type class and instance declarations.
  3285 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  3286 exotic versions of overloading -- at the discretion of the user!
  3287 
  3288 Polymorphic constants are represented via type arguments, i.e. the
  3289 instantiation that matches an instance against the most general
  3290 declaration given in the signature.  For example, with the declaration
  3291 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  3292 as c(nat).  Overloading is essentially simultaneous structural
  3293 recursion over such type arguments.  Incomplete specification patterns
  3294 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  3295 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  3296 Command 'print_theory' outputs the normalized system of recursive
  3297 equations, see section "definitions".
  3298 
  3299 * Configuration options are maintained within the theory or proof
  3300 context (with name and type bool/int/string), providing a very simple
  3301 interface to a poor-man's version of general context data.  Tools may
  3302 declare options in ML (e.g. using Attrib.config_int) and then refer to
  3303 these values using Config.get etc.  Users may change options via an
  3304 associated attribute of the same name.  This form of context
  3305 declaration works particularly well with commands 'declare' or
  3306 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  3307 very easy to avoid global references, which would not observe Isar
  3308 toplevel undo/redo and fail to work with multithreading.
  3309 
  3310 Various global ML references of Pure and HOL have been turned into
  3311 configuration options:
  3312 
  3313   Unify.search_bound		unify_search_bound
  3314   Unify.trace_bound		unify_trace_bound
  3315   Unify.trace_simp		unify_trace_simp
  3316   Unify.trace_types		unify_trace_types
  3317   Simplifier.simp_depth_limit	simp_depth_limit
  3318   Blast.depth_limit		blast_depth_limit
  3319   DatatypeProp.dtK		datatype_distinctness_limit
  3320   fast_arith_neq_limit  	fast_arith_neq_limit
  3321   fast_arith_split_limit	fast_arith_split_limit
  3322 
  3323 * Named collections of theorems may be easily installed as context
  3324 data using the functor NamedThmsFun (see also
  3325 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  3326 attributes; there is also a toplevel print command.  This facility is
  3327 just a common case of general context data, which is the preferred way
  3328 for anything more complex than just a list of facts in canonical
  3329 order.
  3330 
  3331 * Isar: command 'declaration' augments a local theory by generic
  3332 declaration functions written in ML.  This enables arbitrary content
  3333 being added to the context, depending on a morphism that tells the
  3334 difference of the original declaration context wrt. the application
  3335 context encountered later on.
  3336 
  3337 * Isar: proper interfaces for simplification procedures.  Command
  3338 'simproc_setup' declares named simprocs (with match patterns, and body
  3339 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  3340 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  3341 
  3342 * Isar: an extra pair of brackets around attribute declarations
  3343 abbreviates a theorem reference involving an internal dummy fact,
  3344 which will be ignored later --- only the effect of the attribute on
  3345 the background context will persist.  This form of in-place
  3346 declarations is particularly useful with commands like 'declare' and
  3347 'using', for example ``have A using [[simproc a]] by simp''.
  3348 
  3349 * Isar: method "assumption" (and implicit closing of subproofs) now
  3350 takes simple non-atomic goal assumptions into account: after applying
  3351 an assumption as a rule the resulting subgoals are solved by atomic
  3352 assumption steps.  This is particularly useful to finish 'obtain'
  3353 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  3354 without referring to the original premise "!!x. P x ==> thesis" in the
  3355 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  3356 more permissive.
  3357 
  3358 * Isar: implicit use of prems from the Isar proof context is
  3359 considered a legacy feature.  Common applications like ``have A .''
  3360 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  3361 referencing facts explicitly here improves readability and
  3362 maintainability of proof texts.
  3363 
  3364 * Isar: improper proof element 'guess' is like 'obtain', but derives
  3365 the obtained context from the course of reasoning!  For example:
  3366 
  3367   assume "EX x y. A x & B y"   -- "any previous fact"
  3368   then guess x and y by clarify
  3369 
  3370 This technique is potentially adventurous, depending on the facts and
  3371 proof tools being involved here.
  3372 
  3373 * Isar: known facts from the proof context may be specified as literal
  3374 propositions, using ASCII back-quote syntax.  This works wherever
  3375 named facts used to be allowed so far, in proof commands, proof
  3376 methods, attributes etc.  Literal facts are retrieved from the context
  3377 according to unification of type and term parameters.  For example,
  3378 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  3379 theorems in the current context, then these are valid literal facts:
  3380 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  3381 
  3382 There is also a proof method "fact" which does the same composition
  3383 for explicit goal states, e.g. the following proof texts coincide with
  3384 certain special cases of literal facts:
  3385 
  3386   have "A" by fact                 ==  note `A`
  3387   have "A ==> B" by fact           ==  note `A ==> B`
  3388   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  3389   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  3390 
  3391 * Isar: ":" (colon) is no longer a symbolic identifier character in
  3392 outer syntax.  Thus symbolic identifiers may be used without
  3393 additional white space in declarations like this: ``assume *: A''.
  3394 
  3395 * Isar: 'print_facts' prints all local facts of the current context,
  3396 both named and unnamed ones.
  3397 
  3398 * Isar: 'def' now admits simultaneous definitions, e.g.:
  3399 
  3400   def x == "t" and y == "u"
  3401 
  3402 * Isar: added command 'unfolding', which is structurally similar to
  3403 'using', but affects both the goal state and facts by unfolding given
  3404 rewrite rules.  Thus many occurrences of the 'unfold' method or
  3405 'unfolded' attribute may be replaced by first-class proof text.
  3406 
  3407 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  3408 and command 'unfolding' now all support object-level equalities
  3409 (potentially conditional).  The underlying notion of rewrite rule is
  3410 analogous to the 'rule_format' attribute, but *not* that of the
  3411 Simplifier (which is usually more generous).
  3412 
  3413 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  3414 premises of a theorem by n. Useful in conjunction with drule.
  3415 
  3416 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  3417 method expression within a sandbox consisting of the first N
  3418 sub-goals, which need to exist.  For example, ``simp_all [3]''
  3419 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  3420 simplifies all new goals that emerge from applying rule foo to the
  3421 originally first one.
  3422 
  3423 * Isar: schematic goals are no longer restricted to higher-order
  3424 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  3425 expected.
  3426 
  3427 * Isar: the conclusion of a long theorem statement is now either
  3428 'shows' (a simultaneous conjunction, as before), or 'obtains'
  3429 (essentially a disjunction of cases with local parameters and
  3430 assumptions).  The latter allows to express general elimination rules
  3431 adequately; in this notation common elimination rules look like this:
  3432 
  3433   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  3434     assumes "EX x. P x"
  3435     obtains x where "P x"
  3436 
  3437   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  3438     assumes "A & B"
  3439     obtains A and B
  3440 
  3441   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  3442     assumes "A | B"
  3443     obtains
  3444       A
  3445     | B
  3446 
  3447 The subsequent classical rules even refer to the formal "thesis"
  3448 explicitly:
  3449 
  3450   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  3451     obtains "~ thesis"
  3452 
  3453   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  3454     obtains "thesis ==> something"
  3455 
  3456 The actual proof of an 'obtains' statement is analogous to that of the
  3457 Isar proof element 'obtain', only that there may be several cases.
  3458 Optional case names may be specified in parentheses; these will be
  3459 available both in the present proof and as annotations in the
  3460 resulting rule, for later use with the 'cases' method (cf. attribute
  3461 case_names).
  3462 
  3463 * Isar: the assumptions of a long theorem statement are available as
  3464 "assms" fact in the proof context.  This is more appropriate than the
  3465 (historical) "prems", which refers to all assumptions of the current
  3466 context, including those from the target locale, proof body etc.
  3467 
  3468 * Isar: 'print_statement' prints theorems from the current theory or
  3469 proof context in long statement form, according to the syntax of a
  3470 top-level lemma.
  3471 
  3472 * Isar: 'obtain' takes an optional case name for the local context
  3473 introduction rule (default "that").
  3474 
  3475 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  3476 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  3477 to occur.
  3478 
  3479 * Pure: syntax "CONST name" produces a fully internalized constant
  3480 according to the current context.  This is particularly useful for
  3481 syntax translations that should refer to internal constant
  3482 representations independently of name spaces.
  3483 
  3484 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  3485 instead of "FOO ". This allows multiple binder declarations to coexist
  3486 in the same context.  INCOMPATIBILITY.
  3487 
  3488 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  3489 primitive that also works in a locale context (both for constants and
  3490 fixed variables). Type declaration and internal syntactic representation
  3491 of given constants retrieved from the context. Likewise, the
  3492 'no_notation' command allows to remove given syntax annotations from the
  3493 current context.
  3494 
  3495 * Isar/locales: new derived specification elements 'axiomatization',
  3496 'definition', 'abbreviation', which support type-inference, admit
  3497 object-level specifications (equality, equivalence).  See also the
  3498 isar-ref manual.  Examples:
  3499 
  3500   axiomatization
  3501     eq  (infix "===" 50) where
  3502     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  3503 
  3504   definition "f x y = x + y + 1"
  3505   definition g where "g x = f x x"
  3506 
  3507   abbreviation
  3508     neq  (infix "=!=" 50) where
  3509     "x =!= y == ~ (x === y)"
  3510 
  3511 These specifications may be also used in a locale context.  Then the
  3512 constants being introduced depend on certain fixed parameters, and the
  3513 constant name is qualified by the locale base name.  An internal
  3514 abbreviation takes care for convenient input and output, making the
  3515 parameters implicit and using the original short name.  See also
  3516 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  3517 entities from a monomorphic theory.
  3518 
  3519 Presently, abbreviations are only available 'in' a target locale, but
  3520 not inherited by general import expressions.  Also note that
  3521 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  3522 'translations' in common applications.  The "no_abbrevs" print mode
  3523 prevents folding of abbreviations in term output.
  3524 
  3525 Concrete syntax is attached to specified constants in internal form,
  3526 independently of name spaces.  The parse tree representation is
  3527 slightly different -- use 'notation' instead of raw 'syntax', and
  3528 'translations' with explicit "CONST" markup to accommodate this.
  3529 
  3530 * Pure/Isar: unified syntax for new-style specification mechanisms
  3531 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  3532 full type inference and dummy patterns ("_").  For example:
  3533 
  3534   definition "K x _ = x"
  3535 
  3536   inductive conj for A B
  3537   where "A ==> B ==> conj A B"
  3538 
  3539 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  3540 the current context.  Print mode "no_abbrevs" prevents inversion of
  3541 abbreviations on output.
  3542 
  3543 * Isar/locales: improved parameter handling: use of locales "var" and
  3544 "struct" no longer necessary; - parameter renamings are no longer
  3545 required to be injective.  For example, this allows to define
  3546 endomorphisms as locale endom = homom mult mult h.
  3547 
  3548 * Isar/locales: changed the way locales with predicates are defined.
  3549 Instead of accumulating the specification, the imported expression is
  3550 now an interpretation.  INCOMPATIBILITY: different normal form of
  3551 locale expressions.  In particular, in interpretations of locales with
  3552 predicates, goals repesenting already interpreted fragments are not
  3553 removed automatically.  Use methods `intro_locales' and
  3554 `unfold_locales'; see below.
  3555 
  3556 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  3557 provide backward reasoning on locales predicates.  The methods are
  3558 aware of interpretations and discharge corresponding goals.
  3559 `intro_locales' is less aggressive then `unfold_locales' and does not
  3560 unfold predicates to assumptions.
  3561 
  3562 * Isar/locales: the order in which locale fragments are accumulated
  3563 has changed.  This enables to override declarations from fragments due
  3564 to interpretations -- for example, unwanted simp rules.
  3565 
  3566 * Isar/locales: interpretation in theories and proof contexts has been
  3567 extended.  One may now specify (and prove) equations, which are
  3568 unfolded in interpreted theorems.  This is useful for replacing
  3569 defined concepts (constants depending on locale parameters) by
  3570 concepts already existing in the target context.  Example:
  3571 
  3572   interpretation partial_order ["op <= :: [int, int] => bool"]
  3573     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3574 
  3575 Typically, the constant `partial_order.less' is created by a
  3576 definition specification element in the context of locale
  3577 partial_order.
  3578 
  3579 * Method "induct": improved internal context management to support
  3580 local fixes and defines on-the-fly. Thus explicit meta-level
  3581 connectives !!  and ==> are rarely required anymore in inductive goals
  3582 (using object-logic connectives for this purpose has been long
  3583 obsolete anyway). Common proof patterns are explained in
  3584 src/HOL/Induct/Common_Patterns.thy, see also
  3585 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3586 examples.
  3587 
  3588 * Method "induct": improved handling of simultaneous goals. Instead of
  3589 introducing object-level conjunction, the statement is now split into
  3590 several conclusions, while the corresponding symbolic cases are nested
  3591 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3592 see src/HOL/Induct/Common_Patterns.thy, for example.
  3593 
  3594 * Method "induct": mutual induction rules are now specified as a list
  3595 of rule sharing the same induction cases. HOL packages usually provide
  3596 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3597 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3598 mutual induction rules differently, i.e. like this:
  3599 
  3600   (induct rule: foo_bar.inducts)
  3601   (induct set: foo bar)
  3602   (induct pred: foo bar)
  3603   (induct type: foo bar)
  3604 
  3605 The ML function ProjectRule.projections turns old-style rules into the
  3606 new format.
  3607 
  3608 * Method "coinduct": dual of induction, see
  3609 src/HOL/Library/Coinductive_List.thy for various examples.
  3610 
  3611 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3612 considered a legacy feature.
  3613 
  3614 * Attribute "symmetric" produces result with standardized schematic
  3615 variables (index 0).  Potential INCOMPATIBILITY.
  3616 
  3617 * Simplifier: by default the simplifier trace only shows top level
  3618 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3619 default. Thus there is less danger of being flooded by the trace. The
  3620 trace indicates where parts have been suppressed.
  3621   
  3622 * Provers/classical: removed obsolete classical version of elim_format
  3623 attribute; classical elim/dest rules are now treated uniformly when
  3624 manipulating the claset.
  3625 
  3626 * Provers/classical: stricter checks to ensure that supplied intro,
  3627 dest and elim rules are well-formed; dest and elim rules must have at
  3628 least one premise.
  3629 
  3630 * Provers/classical: attributes dest/elim/intro take an optional
  3631 weight argument for the rule (just as the Pure versions).  Weights are
  3632 ignored by automated tools, but determine the search order of single
  3633 rule steps.
  3634 
  3635 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3636 where the body does not mention the bound variable.  Note that dummy
  3637 patterns implicitly depend on their context of bounds, which makes
  3638 "{_. _}" match any set comprehension as expected.  Potential
  3639 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3640 constant "_idtdummy" in the binding position.
  3641 
  3642 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3643 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3644 for example "A -> B" => "Pi A (%_. B)".
  3645 
  3646 * Pure: 'class_deps' command visualizes the subclass relation, using
  3647 the graph browser tool.
  3648 
  3649 * Pure: 'print_theory' now suppresses certain internal declarations by
  3650 default; use '!' option for full details.
  3651 
  3652 
  3653 *** HOL ***
  3654 
  3655 * Method "metis" proves goals by applying the Metis general-purpose
  3656 resolution prover (see also http://gilith.com/software/metis/).
  3657 Examples are in the directory MetisExamples.  WARNING: the
  3658 Isabelle/HOL-Metis integration does not yet work properly with
  3659 multi-threading.
  3660   
  3661 * Command 'sledgehammer' invokes external automatic theorem provers as
  3662 background processes.  It generates calls to the "metis" method if
  3663 successful. These can be pasted into the proof.  Users do not have to
  3664 wait for the automatic provers to return.  WARNING: does not really
  3665 work with multi-threading.
  3666 
  3667 * New "auto_quickcheck" feature tests outermost goal statements for
  3668 potential counter-examples.  Controlled by ML references
  3669 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3670 5000 milliseconds).  Fails silently if statements is outside of
  3671 executable fragment, or any other codgenerator problem occurs.
  3672 
  3673 * New constant "undefined" with axiom "undefined x = undefined".
  3674 
  3675 * Added class "HOL.eq", allowing for code generation with polymorphic
  3676 equality.
  3677 
  3678 * Some renaming of class constants due to canonical name prefixing in
  3679 the new 'class' package:
  3680 
  3681     HOL.abs ~> HOL.abs_class.abs
  3682     HOL.divide ~> HOL.divide_class.divide
  3683     0 ~> HOL.zero_class.zero
  3684     1 ~> HOL.one_class.one
  3685     op + ~> HOL.plus_class.plus
  3686     op - ~> HOL.minus_class.minus
  3687     uminus ~> HOL.minus_class.uminus
  3688     op * ~> HOL.times_class.times
  3689     op < ~> HOL.ord_class.less
  3690     op <= > HOL.ord_class.less_eq
  3691     Nat.power ~> Power.power_class.power
  3692     Nat.size ~> Nat.size_class.size
  3693     Numeral.number_of ~> Numeral.number_class.number_of
  3694     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3695     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3696     Orderings.min ~> Orderings.ord_class.min
  3697     Orderings.max ~> Orderings.ord_class.max
  3698     Divides.op div ~> Divides.div_class.div
  3699     Divides.op mod ~> Divides.div_class.mod
  3700     Divides.op dvd ~> Divides.div_class.dvd
  3701 
  3702 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3703 
  3704 a) User-defined constants using any of the names "plus", "minus",
  3705 "times", "less" or "less_eq". The standard syntax translations for
  3706 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3707 names.
  3708 
  3709 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3710 INCOMPATIBILITY: use more specific names.
  3711 
  3712 c) Permutative equations (e.g. "a + b = b + a")
  3713 Since the change of names also changes the order of terms, permutative
  3714 rewrite rules may get applied in a different order. Experience shows
  3715 that this is rarely the case (only two adaptions in the whole Isabelle
  3716 distribution).  INCOMPATIBILITY: rewrite proofs
  3717 
  3718 d) ML code directly refering to constant names
  3719 This in general only affects hand-written proof tactics, simprocs and
  3720 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3721 Consider using @{const_name} antiquotation.
  3722 
  3723 * New class "default" with associated constant "default".
  3724 
  3725 * Function "sgn" is now overloaded and available on int, real, complex
  3726 (and other numeric types), using class "sgn".  Two possible defs of
  3727 sgn are given as equational assumptions in the classes sgn_if and
  3728 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3729 INCOMPATIBILITY.
  3730 
  3731 * Locale "partial_order" now unified with class "order" (cf. theory
  3732 Orderings), added parameter "less".  INCOMPATIBILITY.
  3733 
  3734 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3735 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3736 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3737 
  3738 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3739 changed order of proof goals in instance proofs.
  3740 
  3741 * The transitivity reasoner for partial and linear orders is set up
  3742 for classes "order" and "linorder".  Instances of the reasoner are available
  3743 in all contexts importing or interpreting the corresponding locales.
  3744 Method "order" invokes the reasoner separately; the reasoner
  3745 is also integrated with the Simplifier as a solver.  Diagnostic
  3746 command 'print_orders' shows the available instances of the reasoner
  3747 in the current context.
  3748 
  3749 * Localized monotonicity predicate in theory "Orderings"; integrated
  3750 lemmas max_of_mono and min_of_mono with this predicate.
  3751 INCOMPATIBILITY.
  3752 
  3753 * Formulation of theorem "dense" changed slightly due to integration
  3754 with new class dense_linear_order.
  3755 
  3756 * Uniform lattice theory development in HOL.
  3757 
  3758     constants "meet" and "join" now named "inf" and "sup"
  3759     constant "Meet" now named "Inf"
  3760 
  3761     classes "meet_semilorder" and "join_semilorder" now named
  3762       "lower_semilattice" and "upper_semilattice"
  3763     class "lorder" now named "lattice"
  3764     class "comp_lat" now named "complete_lattice"
  3765 
  3766     Instantiation of lattice classes allows explicit definitions
  3767     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3768 
  3769   INCOMPATIBILITY.  Theorem renames:
  3770 
  3771     meet_left_le            ~> inf_le1
  3772     meet_right_le           ~> inf_le2
  3773     join_left_le            ~> sup_ge1
  3774     join_right_le           ~> sup_ge2
  3775     meet_join_le            ~> inf_sup_ord
  3776     le_meetI                ~> le_infI
  3777     join_leI                ~> le_supI
  3778     le_meet                 ~> le_inf_iff
  3779     le_join                 ~> ge_sup_conv
  3780     meet_idempotent         ~> inf_idem
  3781     join_idempotent         ~> sup_idem
  3782     meet_comm               ~> inf_commute
  3783     join_comm               ~> sup_commute
  3784     meet_leI1               ~> le_infI1
  3785     meet_leI2               ~> le_infI2
  3786     le_joinI1               ~> le_supI1
  3787     le_joinI2               ~> le_supI2
  3788     meet_assoc              ~> inf_assoc
  3789     join_assoc              ~> sup_assoc
  3790     meet_left_comm          ~> inf_left_commute
  3791     meet_left_idempotent    ~> inf_left_idem
  3792     join_left_comm          ~> sup_left_commute
  3793     join_left_idempotent    ~> sup_left_idem
  3794     meet_aci                ~> inf_aci
  3795     join_aci                ~> sup_aci
  3796     le_def_meet             ~> le_iff_inf
  3797     le_def_join             ~> le_iff_sup
  3798     join_absorp2            ~> sup_absorb2
  3799     join_absorp1            ~> sup_absorb1
  3800     meet_absorp1            ~> inf_absorb1
  3801     meet_absorp2            ~> inf_absorb2
  3802     meet_join_absorp        ~> inf_sup_absorb
  3803     join_meet_absorp        ~> sup_inf_absorb
  3804     distrib_join_le         ~> distrib_sup_le
  3805     distrib_meet_le         ~> distrib_inf_le
  3806 
  3807     add_meet_distrib_left   ~> add_inf_distrib_left
  3808     add_join_distrib_left   ~> add_sup_distrib_left
  3809     is_join_neg_meet        ~> is_join_neg_inf
  3810     is_meet_neg_join        ~> is_meet_neg_sup
  3811     add_meet_distrib_right  ~> add_inf_distrib_right
  3812     add_join_distrib_right  ~> add_sup_distrib_right
  3813     add_meet_join_distribs  ~> add_sup_inf_distribs
  3814     join_eq_neg_meet        ~> sup_eq_neg_inf
  3815     meet_eq_neg_join        ~> inf_eq_neg_sup
  3816     add_eq_meet_join        ~> add_eq_inf_sup
  3817     meet_0_imp_0            ~> inf_0_imp_0
  3818     join_0_imp_0            ~> sup_0_imp_0
  3819     meet_0_eq_0             ~> inf_0_eq_0
  3820     join_0_eq_0             ~> sup_0_eq_0
  3821     neg_meet_eq_join        ~> neg_inf_eq_sup
  3822     neg_join_eq_meet        ~> neg_sup_eq_inf
  3823     join_eq_if              ~> sup_eq_if
  3824 
  3825     mono_meet               ~> mono_inf
  3826     mono_join               ~> mono_sup
  3827     meet_bool_eq            ~> inf_bool_eq
  3828     join_bool_eq            ~> sup_bool_eq
  3829     meet_fun_eq             ~> inf_fun_eq
  3830     join_fun_eq             ~> sup_fun_eq
  3831     meet_set_eq             ~> inf_set_eq
  3832     join_set_eq             ~> sup_set_eq
  3833     meet1_iff               ~> inf1_iff
  3834     meet2_iff               ~> inf2_iff
  3835     meet1I                  ~> inf1I
  3836     meet2I                  ~> inf2I
  3837     meet1D1                 ~> inf1D1
  3838     meet2D1                 ~> inf2D1
  3839     meet1D2                 ~> inf1D2
  3840     meet2D2                 ~> inf2D2
  3841     meet1E                  ~> inf1E
  3842     meet2E                  ~> inf2E
  3843     join1_iff               ~> sup1_iff
  3844     join2_iff               ~> sup2_iff
  3845     join1I1                 ~> sup1I1
  3846     join2I1                 ~> sup2I1
  3847     join1I1                 ~> sup1I1
  3848     join2I2                 ~> sup1I2
  3849     join1CI                 ~> sup1CI
  3850     join2CI                 ~> sup2CI
  3851     join1E                  ~> sup1E
  3852     join2E                  ~> sup2E
  3853 
  3854     is_meet_Meet            ~> is_meet_Inf
  3855     Meet_bool_def           ~> Inf_bool_def
  3856     Meet_fun_def            ~> Inf_fun_def
  3857     Meet_greatest           ~> Inf_greatest
  3858     Meet_lower              ~> Inf_lower
  3859     Meet_set_def            ~> Inf_set_def
  3860 
  3861     Sup_def                 ~> Sup_Inf
  3862     Sup_bool_eq             ~> Sup_bool_def
  3863     Sup_fun_eq              ~> Sup_fun_def
  3864     Sup_set_eq              ~> Sup_set_def
  3865 
  3866     listsp_meetI            ~> listsp_infI
  3867     listsp_meet_eq          ~> listsp_inf_eq
  3868 
  3869     meet_min                ~> inf_min
  3870     join_max                ~> sup_max
  3871 
  3872 * Added syntactic class "size"; overloaded constant "size" now has
  3873 type "'a::size ==> bool"
  3874 
  3875 * Internal reorganisation of `size' of datatypes: size theorems
  3876 "foo.size" are no longer subsumed by "foo.simps" (but are still
  3877 simplification rules by default!); theorems "prod.size" now named
  3878 "*.size".
  3879 
  3880 * Class "div" now inherits from class "times" rather than "type".
  3881 INCOMPATIBILITY.
  3882 
  3883 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  3884 Linorder etc.  have disappeared; operations defined in terms of
  3885 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  3886 
  3887 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  3888 
  3889 * HOL-Word: New extensive library and type for generic, fixed size
  3890 machine words, with arithemtic, bit-wise, shifting and rotating
  3891 operations, reflection into int, nat, and bool lists, automation for
  3892 linear arithmetic (by automatic reflection into nat or int), including
  3893 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  3894 arithmetic type classes, supporting automatic simplification of
  3895 numerals on all operations.
  3896 
  3897 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  3898 
  3899 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  3900 
  3901 * Code generator library theories:
  3902   - Code_Integer represents HOL integers by big integer literals in target
  3903     languages.
  3904   - Code_Char represents HOL characters by character literals in target
  3905     languages.
  3906   - Code_Char_chr like Code_Char, but also offers treatment of character
  3907     codes; includes Code_Integer.
  3908   - Executable_Set allows to generate code for finite sets using lists.
  3909   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  3910     denominator).
  3911   - Executable_Real implements a subset of real numbers, namly those
  3912     representable by rational numbers.
  3913   - Efficient_Nat implements natural numbers by integers, which in general will
  3914     result in higher efficency; pattern matching with 0/Suc is eliminated;
  3915     includes Code_Integer.
  3916   - Code_Index provides an additional datatype index which is mapped to
  3917     target-language built-in integers.
  3918   - Code_Message provides an additional datatype message_string which is isomorphic to
  3919     strings; messages are mapped to target-language strings.
  3920 
  3921 * New package for inductive predicates
  3922 
  3923   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  3924 
  3925     inductive
  3926       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3927       for z_1 :: U_1 and ... and z_n :: U_m
  3928     where
  3929       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3930     | ...
  3931 
  3932   with full support for type-inference, rather than
  3933 
  3934     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3935 
  3936     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3937     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3938 
  3939     inductive "s z_1 ... z_m"
  3940     intros
  3941       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3942       ...
  3943 
  3944   For backward compatibility, there is a wrapper allowing inductive
  3945   sets to be defined with the new package via
  3946 
  3947     inductive_set
  3948       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3949       for z_1 :: U_1 and ... and z_n :: U_m
  3950     where
  3951       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3952     | ...
  3953 
  3954   or
  3955 
  3956     inductive_set
  3957       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3958       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3959       for z_1 :: U_1 and ... and z_n :: U_m
  3960     where
  3961       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3962     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3963     | ...
  3964 
  3965   if the additional syntax "p ..." is required.
  3966 
  3967   Numerous examples can be found in the subdirectories src/HOL/Auth,
  3968   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  3969 
  3970   INCOMPATIBILITIES:
  3971 
  3972   - Since declaration and definition of inductive sets or predicates
  3973     is no longer separated, abbreviations involving the newly
  3974     introduced sets or predicates must be specified together with the
  3975     introduction rules after the 'where' keyword (see above), rather
  3976     than before the actual inductive definition.
  3977 
  3978   - The variables in induction and elimination rules are now
  3979     quantified in the order of their occurrence in the introduction
  3980     rules, rather than in alphabetical order. Since this may break
  3981     some proofs, these proofs either have to be repaired, e.g. by
  3982     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  3983     statements of the form
  3984 
  3985       case (rule_i a_i_1 ... a_i_{k_i})
  3986 
  3987     or the old order of quantification has to be restored by explicitly adding
  3988     meta-level quantifiers in the introduction rules, i.e.
  3989 
  3990       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  3991 
  3992   - The format of the elimination rules is now
  3993 
  3994       p z_1 ... z_m x_1 ... x_n ==>
  3995         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  3996         ==> ... ==> P
  3997 
  3998     for predicates and
  3999 
  4000       (x_1, ..., x_n) : s z_1 ... z_m ==>
  4001         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4002         ==> ... ==> P
  4003 
  4004     for sets rather than
  4005 
  4006       x : s z_1 ... z_m ==>
  4007         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  4008         ==> ... ==> P
  4009 
  4010     This may require terms in goals to be expanded to n-tuples
  4011     (e.g. using case_tac or simplification with the split_paired_all
  4012     rule) before the above elimination rule is applicable.
  4013 
  4014   - The elimination or case analysis rules for (mutually) inductive
  4015     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  4016     list of rules "p_1_..._p_k.elims" is no longer available.
  4017 
  4018 * New package "function"/"fun" for general recursive functions,
  4019 supporting mutual and nested recursion, definitions in local contexts,
  4020 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  4021 for small examples, and the separate tutorial on the function
  4022 package. The old recdef "package" is still available as before, but
  4023 users are encouraged to use the new package.
  4024 
  4025 * Method "lexicographic_order" automatically synthesizes termination
  4026 relations as lexicographic combinations of size measures. 
  4027 
  4028 * Case-expressions allow arbitrary constructor-patterns (including
  4029 "_") and take their order into account, like in functional
  4030 programming.  Internally, this is translated into nested
  4031 case-expressions; missing cases are added and mapped to the predefined
  4032 constant "undefined". In complicated cases printing may no longer show
  4033 the original input but the internal form. Lambda-abstractions allow
  4034 the same form of pattern matching: "% pat1 => e1 | ..." is an
  4035 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  4036 variable.
  4037 
  4038 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  4039 is an abbreviation for "of_nat :: nat => int". The simplification
  4040 rules for "of_nat" have been changed to work like "int" did
  4041 previously.  Potential INCOMPATIBILITY:
  4042   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  4043   - of_nat_diff and of_nat_mult are no longer default simp rules
  4044 
  4045 * Method "algebra" solves polynomial equations over (semi)rings using
  4046 Groebner bases. The (semi)ring structure is defined by locales and the
  4047 tool setup depends on that generic context. Installing the method for
  4048 a specific type involves instantiating the locale and possibly adding
  4049 declarations for computation on the coefficients.  The method is
  4050 already instantiated for natural numbers and for the axiomatic class
  4051 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  4052 CALCULEMUS 2007 for the general principles underlying this
  4053 architecture of context-aware proof-tools.
  4054 
  4055 * Method "ferrack" implements quantifier elimination over
  4056 special-purpose dense linear orders using locales (analogous to
  4057 "algebra"). The method is already installed for class
  4058 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  4059 rat, etc.
  4060 
  4061 * Former constant "List.op @" now named "List.append".  Use ML
  4062 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  4063 circumvent possible incompatibilities when working on ML level.
  4064 
  4065 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  4066 
  4067 * New function listsum :: 'a list => 'a for arbitrary monoids.
  4068 Special syntax: "SUM x <- xs. f x" (and latex variants)
  4069 
  4070 * New syntax for Haskell-like list comprehension (input only), eg.
  4071 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  4072 
  4073 * The special syntax for function "filter" has changed from [x :
  4074 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  4075 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  4076 
  4077 * [a..b] is now defined for arbitrary linear orders.  It used to be
  4078 defined on nat only, as an abbreviation for [a..<Suc b]
  4079 INCOMPATIBILITY.
  4080 
  4081 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  4082 
  4083 * New functions "sorted" and "sort" in src/HOL/List.thy.
  4084 
  4085 * New lemma collection field_simps (an extension of ring_simps) for
  4086 manipulating (in)equations involving division. Multiplies with all
  4087 denominators that can be proved to be non-zero (in equations) or
  4088 positive/negative (in inequations).
  4089 
  4090 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  4091 have been improved and renamed to ring_simps, group_simps and
  4092 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  4093 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  4094 
  4095 * Theory Library/Commutative_Ring: switched from recdef to function
  4096 package; constants add, mul, pow now curried.  Infix syntax for
  4097 algebraic operations.
  4098 
  4099 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  4100 INCOMPATIBILITY.
  4101 
  4102 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  4103 INCOMPATIBILITY.
  4104 
  4105 * HOL/records: generalised field-update to take a function on the
  4106 field rather than the new value: r(|A := x|) is translated to A_update
  4107 (K x) r The K-combinator that is internally used is called K_record.
  4108 INCOMPATIBILITY: Usage of the plain update functions has to be
  4109 adapted.
  4110  
  4111 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  4112 * x = 0, which are required for a semiring.  Richer structures do not
  4113 inherit from semiring_0 anymore, because this property is a theorem
  4114 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  4115 there is more to prove, but this is mostly trivial.
  4116 
  4117 * Class "recpower" is generalized to arbitrary monoids, not just
  4118 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  4119 commutativity or semiring properties additionally.
  4120 
  4121 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  4122 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  4123 better use 'abbreviation'.
  4124 
  4125 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  4126 
  4127 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  4128 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  4129 significant changes for setting up numeral syntax for types:
  4130   - New constants Numeral.pred and Numeral.succ instead
  4131       of former Numeral.bin_pred and Numeral.bin_succ.
  4132   - Use integer operations instead of bin_add, bin_mult and so on.
  4133   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  4134   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  4135 
  4136 See src/HOL/Integ/IntArith.thy for an example setup.
  4137 
  4138 * Command 'normal_form' computes the normal form of a term that may
  4139 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  4140 produces ``[b, c, a]'' (without proof).  This command is suitable for
  4141 heavy-duty computations because the functions are compiled to ML
  4142 first.  Correspondingly, a method "normalization" is provided.  See
  4143 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  4144 
  4145 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  4146 25 like -->); output depends on the "iff" print_mode, the default is
  4147 "A = B" (with priority 50).
  4148 
  4149 * Relations less (<) and less_eq (<=) are also available on type bool.
  4150 Modified syntax to disallow nesting without explicit parentheses,
  4151 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  4152 INCOMPATIBILITY.
  4153 
  4154 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  4155 
  4156 * Relation composition operator "op O" now has precedence 75 and binds
  4157 stronger than union and intersection. INCOMPATIBILITY.
  4158 
  4159 * The old set interval syntax "{m..n(}" (and relatives) has been
  4160 removed.  Use "{m..<n}" (and relatives) instead.
  4161 
  4162 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  4163 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  4164 ``declare [[simproc del: neq]]''.
  4165 
  4166 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  4167 True/False.
  4168 
  4169 * Theorem Cons_eq_map_conv no longer declared as "simp".
  4170 
  4171 * Theorem setsum_mult renamed to setsum_right_distrib.
  4172 
  4173 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  4174 ``rule'' method.
  4175 
  4176 * Reimplemented methods "sat" and "satx", with several improvements:
  4177 goals no longer need to be stated as "<prems> ==> False", equivalences
  4178 (i.e. "=" on type bool) are handled, variable names of the form
  4179 "lit_<n>" are no longer reserved, significant speedup.
  4180 
  4181 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  4182 zChaff is still supported as well.
  4183 
  4184 * 'inductive' and 'datatype': provide projections of mutual rules,
  4185 bundled as foo_bar.inducts;
  4186 
  4187 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  4188 Library.
  4189 
  4190 * Library: moved theory Accessible_Part to main HOL.
  4191 
  4192 * Library: added theory Coinductive_List of potentially infinite lists
  4193 as greatest fixed-point.
  4194 
  4195 * Library: added theory AssocList which implements (finite) maps as
  4196 association lists.
  4197 
  4198 * Method "evaluation" solves goals (i.e. a boolean expression)
  4199 efficiently by compiling it to ML.  The goal is "proved" (via an
  4200 oracle) if it evaluates to True.
  4201 
  4202 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  4203 also when invoked by the simplifier.  This results in the Simplifier
  4204 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  4205 Configuration option fast_arith_split_limit=0 recovers the old
  4206 behavior.
  4207 
  4208 * Support for hex (0x20) and binary (0b1001) numerals.
  4209 
  4210 * New method: reify eqs (t), where eqs are equations for an
  4211 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  4212 parameter, computes a term s::'b and a list xs::'a list and proves the
  4213 theorem I xs s = t. This is also known as reification or quoting. The
  4214 resulting theorem is applied to the subgoal to substitute t with I xs
  4215 s.  If t is omitted, the subgoal itself is reified.
  4216 
  4217 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  4218 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  4219 where f is supposed to be a computable function (in the sense of code
  4220 generattion). The method uses reify to compute s and xs as above then
  4221 applies corr_thm and uses normalization by evaluation to "prove" f s =
  4222 r and finally gets the theorem t = r, which is again applied to the
  4223 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  4224 
  4225 * Reflection: Automatic reification now handels binding, an example is
  4226 available in src/HOL/ex/ReflectionEx.thy
  4227 
  4228 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  4229 command 'statespace' that is similar to 'record', but introduces an
  4230 abstract specification based on the locale infrastructure instead of
  4231 HOL types.  This leads to extra flexibility in composing state spaces,
  4232 in particular multiple inheritance and renaming of components.
  4233 
  4234 
  4235 *** HOL-Complex ***
  4236 
  4237 * Hyperreal: Functions root and sqrt are now defined on negative real
  4238 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  4239 Nonnegativity side conditions have been removed from many lemmas, so
  4240 that more subgoals may now be solved by simplification; potential
  4241 INCOMPATIBILITY.
  4242 
  4243 * Real: new type classes formalize real normed vector spaces and
  4244 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  4245 and norm :: 'a => real.
  4246 
  4247 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  4248 reals into other types. The overloaded constant Reals :: 'a set is now
  4249 defined as range of_real; potential INCOMPATIBILITY.
  4250 
  4251 * Real: proper support for ML code generation, including 'quickcheck'.
  4252 Reals are implemented as arbitrary precision rationals.
  4253 
  4254 * Hyperreal: Several constants that previously worked only for the
  4255 reals have been generalized, so they now work over arbitrary vector
  4256 spaces. Type annotations may need to be added in some cases; potential
  4257 INCOMPATIBILITY.
  4258 
  4259   Infinitesimal  :: ('a::real_normed_vector) star set
  4260   HFinite        :: ('a::real_normed_vector) star set
  4261   HInfinite      :: ('a::real_normed_vector) star set
  4262   approx         :: ('a::real_normed_vector) star => 'a star => bool
  4263   monad          :: ('a::real_normed_vector) star => 'a star set
  4264   galaxy         :: ('a::real_normed_vector) star => 'a star set
  4265   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  4266   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  4267   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  4268   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  4269   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  4270   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  4271   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  4272   sgn            :: 'a::real_normed_vector => 'a
  4273   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  4274 
  4275 * Complex: Some complex-specific constants are now abbreviations for
  4276 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  4277 hnorm.  Other constants have been entirely removed in favor of the
  4278 polymorphic versions (INCOMPATIBILITY):
  4279 
  4280   approx        <-- capprox
  4281   HFinite       <-- CFinite
  4282   HInfinite     <-- CInfinite
  4283   Infinitesimal <-- CInfinitesimal
  4284   monad         <-- cmonad
  4285   galaxy        <-- cgalaxy
  4286   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  4287   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  4288   (ns)deriv     <-- (ns)cderiv
  4289 
  4290 
  4291 *** HOL-Algebra ***
  4292 
  4293 * Formalisation of ideals and the quotient construction over rings.
  4294 
  4295 * Order and lattice theory no longer based on records.
  4296 INCOMPATIBILITY.
  4297 
  4298 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  4299 greatest_closed.  INCOMPATIBILITY.
  4300 
  4301 * Method algebra is now set up via an attribute.  For examples see
  4302 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  4303 of algebraic structures.
  4304 
  4305 * Renamed theory CRing to Ring.
  4306 
  4307 
  4308 *** HOL-Nominal ***
  4309 
  4310 * Substantial, yet incomplete support for nominal datatypes (binding
  4311 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  4312 src/HOL/Nominal/Examples.  Prospective users should consult
  4313 http://isabelle.in.tum.de/nominal/
  4314 
  4315 
  4316 *** ML ***
  4317 
  4318 * ML basics: just one true type int, which coincides with IntInf.int
  4319 (even on SML/NJ).
  4320 
  4321 * ML within Isar: antiquotations allow to embed statically-checked
  4322 formal entities in the source, referring to the context available at
  4323 compile-time.  For example:
  4324 
  4325 ML {* @{sort "{zero,one}"} *}
  4326 ML {* @{typ "'a => 'b"} *}
  4327 ML {* @{term "%x. x"} *}
  4328 ML {* @{prop "x == y"} *}
  4329 ML {* @{ctyp "'a => 'b"} *}
  4330 ML {* @{cterm "%x. x"} *}
  4331 ML {* @{cprop "x == y"} *}
  4332 ML {* @{thm asm_rl} *}
  4333 ML {* @{thms asm_rl} *}
  4334 ML {* @{type_name c} *}
  4335 ML {* @{type_syntax c} *}
  4336 ML {* @{const_name c} *}
  4337 ML {* @{const_syntax c} *}
  4338 ML {* @{context} *}
  4339 ML {* @{theory} *}
  4340 ML {* @{theory Pure} *}
  4341 ML {* @{theory_ref} *}
  4342 ML {* @{theory_ref Pure} *}
  4343 ML {* @{simpset} *}
  4344 ML {* @{claset} *}
  4345 ML {* @{clasimpset} *}
  4346 
  4347 The same works for sources being ``used'' within an Isar context.
  4348 
  4349 * ML in Isar: improved error reporting; extra verbosity with
  4350 ML_Context.trace enabled.
  4351 
  4352 * Pure/General/table.ML: the join operations now works via exceptions
  4353 DUP/SAME instead of type option. This is simpler in simple cases, and
  4354 admits slightly more efficient complex applications.
  4355 
  4356 * Pure: 'advanced' translation functions (parse_translation etc.) now
  4357 use Context.generic instead of just theory.
  4358 
  4359 * Pure: datatype Context.generic joins theory/Proof.context and
  4360 provides some facilities for code that works in either kind of
  4361 context, notably GenericDataFun for uniform theory and proof data.
  4362 
  4363 * Pure: simplified internal attribute type, which is now always
  4364 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  4365 local (Proof.context) attributes have been discontinued, while
  4366 minimizing code duplication. Thm.rule_attribute and
  4367 Thm.declaration_attribute build canonical attributes; see also structure
  4368 Context for further operations on Context.generic, notably
  4369 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  4370 declarations and definitions.
  4371 
  4372 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  4373 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  4374 init only required for impure data. INCOMPATIBILITY: empty really need
  4375 to be empty (no dependencies on theory content!)
  4376 
  4377 * Pure/kernel: consts certification ignores sort constraints given in
  4378 signature declarations. (This information is not relevant to the
  4379 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  4380 potential INCOMPATIBILITY.
  4381 
  4382 * Pure: axiomatic type classes are now purely definitional, with
  4383 explicit proofs of class axioms and super class relations performed
  4384 internally. See Pure/axclass.ML for the main internal interfaces --
  4385 notably AxClass.define_class supercedes AxClass.add_axclass, and
  4386 AxClass.axiomatize_class/classrel/arity supersede
  4387 Sign.add_classes/classrel/arities.
  4388 
  4389 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  4390 global/local versions on theory vs. Proof.context have been
  4391 discontinued; Attrib.syntax and Method.syntax have been adapted
  4392 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  4393 attributes, methods, etc.
  4394 
  4395 * Pure: several functions of signature "... -> theory -> theory * ..."
  4396 have been reoriented to "... -> theory -> ... * theory" in order to
  4397 allow natural usage in combination with the ||>, ||>>, |-> and
  4398 fold_map combinators.
  4399 
  4400 * Pure: official theorem names (closed derivations) and additional
  4401 comments (tags) are now strictly separate.  Name hints -- which are
  4402 maintained as tags -- may be attached any time without affecting the
  4403 derivation.
  4404 
  4405 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  4406 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  4407 achieve the old behaviour.
  4408 
  4409 * Pure: the "Goal" constant is now called "prop", supporting a
  4410 slightly more general idea of ``protecting'' meta-level rule
  4411 statements.
  4412 
  4413 * Pure: Logic.(un)varify only works in a global context, which is now
  4414 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  4415 Logic.legacy_(un)varify as temporary workaround.
  4416 
  4417 * Pure: structure Name provides scalable operations for generating
  4418 internal variable names, notably Name.variants etc.  This replaces
  4419 some popular functions from term.ML:
  4420 
  4421   Term.variant		->  Name.variant
  4422   Term.variantlist	->  Name.variant_list
  4423   Term.invent_names	->  Name.invent_list
  4424 
  4425 Note that low-level renaming rarely occurs in new code -- operations
  4426 from structure Variable are used instead (see below).
  4427 
  4428 * Pure: structure Variable provides fundamental operations for proper
  4429 treatment of fixed/schematic variables in a context.  For example,
  4430 Variable.import introduces fixes for schematics of given facts and
  4431 Variable.export reverses the effect (up to renaming) -- this replaces
  4432 various freeze_thaw operations.
  4433 
  4434 * Pure: structure Goal provides simple interfaces for
  4435 init/conclude/finish and tactical prove operations (replacing former
  4436 Tactic.prove).  Goal.prove is the canonical way to prove results
  4437 within a given context; Goal.prove_global is a degraded version for
  4438 theory level goals, including a global Drule.standard.  Note that
  4439 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  4440 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  4441 in a locale context).
  4442 
  4443 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  4444 and type checking (Syntax.check_term etc.), with common combinations
  4445 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  4446 which are considered legacy and await removal.
  4447 
  4448 * Pure/Syntax: generic interfaces for type unchecking
  4449 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  4450 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  4451 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  4452 available for convenience, but refer to the very same operations using
  4453 a mere theory instead of a full context.
  4454 
  4455 * Isar: simplified treatment of user-level errors, using exception
  4456 ERROR of string uniformly.  Function error now merely raises ERROR,
  4457 without any side effect on output channels.  The Isar toplevel takes
  4458 care of proper display of ERROR exceptions.  ML code may use plain
  4459 handle/can/try; cat_error may be used to concatenate errors like this:
  4460 
  4461   ... handle ERROR msg => cat_error msg "..."
  4462 
  4463 Toplevel ML code (run directly or through the Isar toplevel) may be
  4464 embedded into the Isar toplevel with exception display/debug like
  4465 this:
  4466 
  4467   Isar.toplevel (fn () => ...)
  4468 
  4469 INCOMPATIBILITY, removed special transform_error facilities, removed
  4470 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  4471 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  4472 -- use plain ERROR instead.
  4473 
  4474 * Isar: theory setup now has type (theory -> theory), instead of a
  4475 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  4476 
  4477 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  4478 ProofContext.debug/verbose flags.
  4479 
  4480 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  4481 theory before entering a proof state.  Transactions now always see a
  4482 quasi-functional intermediate checkpoint, both in interactive and
  4483 batch mode.
  4484 
  4485 * Isar: simplified interfaces for outer syntax.  Renamed
  4486 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  4487 OuterSyntax.add_parsers -- this functionality is now included in
  4488 OuterSyntax.command etc.  INCOMPATIBILITY.
  4489 
  4490 * Simplifier: the simpset of a running simplification process now
  4491 contains a proof context (cf. Simplifier.the_context), which is the
  4492 very context that the initial simpset has been retrieved from (by
  4493 simpset_of/local_simpset_of).  Consequently, all plug-in components
  4494 (solver, looper etc.) may depend on arbitrary proof data.
  4495 
  4496 * Simplifier.inherit_context inherits the proof context (plus the
  4497 local bounds) of the current simplification process; any simproc
  4498 etc. that calls the Simplifier recursively should do this!  Removed
  4499 former Simplifier.inherit_bounds, which is already included here --
  4500 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  4501 specify an explicit context using Simplifier.context/theory_context.
  4502 
  4503 * Simplifier/Classical Reasoner: more abstract interfaces
  4504 change_simpset/claset for modifying the simpset/claset reference of a
  4505 theory; raw versions simpset/claset_ref etc. have been discontinued --
  4506 INCOMPATIBILITY.
  4507 
  4508 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  4509 "Trueprop" etc.
  4510 
  4511 
  4512 *** System ***
  4513 
  4514 * settings: the default heap location within ISABELLE_HOME_USER now
  4515 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  4516 Isabelle installations.
  4517 
  4518 * isabelle-process: option -S (secure mode) disables some critical
  4519 operations, notably runtime compilation and evaluation of ML source
  4520 code.
  4521 
  4522 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  4523 
  4524 * Support for parallel execution, using native multicore support of
  4525 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  4526 independent theories, according to the given theory header
  4527 specifications. The maximum number of worker threads is specified via
  4528 usedir option -M or the "max-threads" setting in Proof General. A
  4529 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  4530 to 6 on a 8-core machine.  User-code needs to observe certain
  4531 guidelines for thread-safe programming, see appendix A in the Isar
  4532 Implementation manual.
  4533 
  4534 
  4535 
  4536 New in Isabelle2005 (October 2005)
  4537 ----------------------------------
  4538 
  4539 *** General ***
  4540 
  4541 * Theory headers: the new header syntax for Isar theories is
  4542 
  4543   theory <name>
  4544   imports <theory1> ... <theoryN>
  4545   uses <file1> ... <fileM>
  4546   begin
  4547 
  4548 where the 'uses' part is optional.  The previous syntax
  4549 
  4550   theory <name> = <theory1> + ... + <theoryN>:
  4551 
  4552 will disappear in the next release.  Use isatool fixheaders to convert
  4553 existing theory files.  Note that there is no change in ancient
  4554 non-Isar theories now, but these will disappear soon.
  4555 
  4556 * Theory loader: parent theories can now also be referred to via
  4557 relative and absolute paths.
  4558 
  4559 * Command 'find_theorems' searches for a list of criteria instead of a
  4560 list of constants. Known criteria are: intro, elim, dest, name:string,
  4561 simp:term, and any term. Criteria can be preceded by '-' to select
  4562 theorems that do not match. Intro, elim, dest select theorems that
  4563 match the current goal, name:s selects theorems whose fully qualified
  4564 name contain s, and simp:term selects all simplification rules whose
  4565 lhs match term.  Any other term is interpreted as pattern and selects
  4566 all theorems matching the pattern. Available in ProofGeneral under
  4567 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  4568 
  4569   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  4570 
  4571 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  4572 matching the current goal as introduction rule and not having "HOL."
  4573 in their name (i.e. not being defined in theory HOL).
  4574 
  4575 * Command 'thms_containing' has been discontinued in favour of
  4576 'find_theorems'; INCOMPATIBILITY.
  4577 
  4578 * Communication with Proof General is now 8bit clean, which means that
  4579 Unicode text in UTF-8 encoding may be used within theory texts (both
  4580 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4581 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4582 
  4583   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4584   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4585 
  4586 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4587 Classical Reasoner.  Typical big applications run around 2 times
  4588 faster.
  4589 
  4590 
  4591 *** Document preparation ***
  4592 
  4593 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4594 of raw sources.  Only those symbols that do not require additional
  4595 LaTeX packages (depending on comments in isabellesym.sty) are
  4596 displayed properly, everything else is left verbatim.  isatool display
  4597 and isatool print are used as front ends (these are subject to the
  4598 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4599 
  4600 * Command tags control specific markup of certain regions of text,
  4601 notably folding and hiding.  Predefined tags include "theory" (for
  4602 theory begin and end), "proof" for proof commands, and "ML" for
  4603 commands involving ML code; the additional tags "visible" and
  4604 "invisible" are unused by default.  Users may give explicit tag
  4605 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4606 interpretation of tags is determined by the LaTeX job during document
  4607 preparation: see option -V of isatool usedir, or options -n and -t of
  4608 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4609 \isadroptag.
  4610 
  4611 Several document versions may be produced at the same time via isatool
  4612 usedir (the generated index.html will link all of them).  Typical
  4613 specifications include ''-V document=theory,proof,ML'' to present
  4614 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4615 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4616 these parts without any formal replacement text.  The Isabelle site
  4617 default settings produce ''document'' and ''outline'' versions as
  4618 specified above.
  4619 
  4620 * Several new antiquotations:
  4621 
  4622   @{term_type term} prints a term with its type annotated;
  4623 
  4624   @{typeof term} prints the type of a term;
  4625 
  4626   @{const const} is the same as @{term const}, but checks that the
  4627   argument is a known logical constant;
  4628 
  4629   @{term_style style term} and @{thm_style style thm} print a term or
  4630   theorem applying a "style" to it
  4631 
  4632   @{ML text}
  4633 
  4634 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4635 definitions, equations, inequations etc., 'concl' printing only the
  4636 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4637 to print the specified premise.  TermStyle.add_style provides an ML
  4638 interface for introducing further styles.  See also the "LaTeX Sugar"
  4639 document practical applications.  The ML antiquotation prints
  4640 type-checked ML expressions verbatim.
  4641 
  4642 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4643 and 'text' support optional locale specification '(in loc)', which
  4644 specifies the default context for interpreting antiquotations.  For
  4645 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4646 
  4647 * Option 'locale=NAME' of antiquotations specifies an alternative
  4648 context interpreting the subsequent argument.  For example: @{thm
  4649 [locale=lattice] inf_assoc}.
  4650 
  4651 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4652 a proof context.
  4653 
  4654 * Proper output of antiquotations for theory commands involving a
  4655 proof context (such as 'locale' or 'theorem (in loc) ...').
  4656 
  4657 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4658 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4659 
  4660 * isatool usedir: new option -C (default true) controls whether option
  4661 -D should include a copy of the original document directory; -C false
  4662 prevents unwanted effects such as copying of administrative CVS data.
  4663 
  4664 
  4665 *** Pure ***
  4666 
  4667 * Considerably improved version of 'constdefs' command.  Now performs
  4668 automatic type-inference of declared constants; additional support for
  4669 local structure declarations (cf. locales and HOL records), see also
  4670 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4671 sequential dependencies of definitions within a single 'constdefs'
  4672 section; moreover, the declared name needs to be an identifier.  If
  4673 all fails, consider to fall back on 'consts' and 'defs' separately.
  4674 
  4675 * Improved indexed syntax and implicit structures.  First of all,
  4676 indexed syntax provides a notational device for subscripted
  4677 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4678 expressions.  Secondly, in a local context with structure
  4679 declarations, number indexes \<^sub>n or the empty index (default
  4680 number 1) refer to a certain fixed variable implicitly; option
  4681 show_structs controls printing of implicit structures.  Typical
  4682 applications of these concepts involve record types and locales.
  4683 
  4684 * New command 'no_syntax' removes grammar declarations (and
  4685 translations) resulting from the given syntax specification, which is
  4686 interpreted in the same manner as for the 'syntax' command.
  4687 
  4688 * 'Advanced' translation functions (parse_translation etc.) may depend
  4689 on the signature of the theory context being presently used for
  4690 parsing/printing, see also isar-ref manual.
  4691 
  4692 * Improved 'oracle' command provides a type-safe interface to turn an
  4693 ML expression of type theory -> T -> term into a primitive rule of
  4694 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4695 is already included here); see also FOL/ex/IffExample.thy;
  4696 INCOMPATIBILITY.
  4697 
  4698 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4699 before); "cI" is no longer bound, use "c.intro" instead.
  4700 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4701 axclasses vs. locales.
  4702 
  4703 * Improved internal renaming of symbolic identifiers -- attach primes
  4704 instead of base 26 numbers.
  4705 
  4706 * New flag show_question_marks controls printing of leading question
  4707 marks in schematic variable names.
  4708 
  4709 * In schematic variable names, *any* symbol following \<^isub> or
  4710 \<^isup> is now treated as part of the base name.  For example, the
  4711 following works without printing of awkward ".0" indexes:
  4712 
  4713   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4714     by simp
  4715 
  4716 * Inner syntax includes (*(*nested*) comments*).
  4717 
  4718 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4719 annotations as "(00...)".
  4720 
  4721 * Clear separation of logical types and nonterminals, where the latter
  4722 may only occur in 'syntax' specifications or type abbreviations.
  4723 Before that distinction was only partially implemented via type class
  4724 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4725 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4726 exotic syntax specifications may require further adaption
  4727 (e.g. Cube/Cube.thy).
  4728 
  4729 * Removed obsolete type class "logic", use the top sort {} instead.
  4730 Note that non-logical types should be declared as 'nonterminals'
  4731 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4732 specifications.
  4733 
  4734 * Attributes 'induct' and 'cases': type or set names may now be
  4735 locally fixed variables as well.
  4736 
  4737 * Simplifier: can now control the depth to which conditional rewriting
  4738 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4739 Limit.
  4740 
  4741 * Simplifier: simplification procedures may now take the current
  4742 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4743 interface), which is very useful for calling the Simplifier
  4744 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4745 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4746 low-level mk_simproc no longer applies Logic.varify internally, to
  4747 allow for use in a context of fixed variables.
  4748 
  4749 * thin_tac now works even if the assumption being deleted contains !!
  4750 or ==>.  More generally, erule now works even if the major premise of
  4751 the elimination rule contains !! or ==>.
  4752 
  4753 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4754 
  4755 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4756 from Pure, which contains all common declarations already.  Both
  4757 theories are defined via plain Isabelle/Isar .thy files.
  4758 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4759 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4760 use isatool fixcpure to adapt your theory and ML sources.
  4761 
  4762 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4763 selections of theorems in named facts via index ranges.
  4764 
  4765 * 'print_theorems': in theory mode, really print the difference
  4766 wrt. the last state (works for interactive theory development only),
  4767 in proof mode print all local facts (cf. 'print_facts');
  4768 
  4769 * 'hide': option '(open)' hides only base names.
  4770 
  4771 * More efficient treatment of intermediate checkpoints in interactive
  4772 theory development.
  4773 
  4774 * Code generator is now invoked via code_module (incremental code
  4775 generation) and code_library (modular code generation, ML structures
  4776 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4777 must be quoted when used as identifiers.
  4778 
  4779 * New 'value' command for reading, evaluating and printing terms using
  4780 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4781 quoted when used as identifier.
  4782 
  4783 
  4784 *** Locales ***
  4785 
  4786 * New commands for the interpretation of locale expressions in
  4787 theories (1), locales (2) and proof contexts (3).  These generate
  4788 proof obligations from the expression specification.  After the
  4789 obligations have been discharged, theorems of the expression are added
  4790 to the theory, target locale or proof context.  The synopsis of the
  4791 commands is a follows:
  4792 
  4793   (1) interpretation expr inst
  4794   (2) interpretation target < expr
  4795   (3) interpret expr inst
  4796 
  4797 Interpretation in theories and proof contexts require a parameter
  4798 instantiation of terms from the current context.  This is applied to
  4799 specifications and theorems of the interpreted expression.
  4800 Interpretation in locales only permits parameter renaming through the
  4801 locale expression.  Interpretation is smart in that interpretations
  4802 that are active already do not occur in proof obligations, neither are
  4803 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4804 inspect active interpretations of a particular locale.  For details,
  4805 see the Isar Reference manual.  Examples can be found in
  4806 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4807 
  4808 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4809 'interpret' instead.
  4810 
  4811 * New context element 'constrains' for adding type constraints to
  4812 parameters.
  4813 
  4814 * Context expressions: renaming of parameters with syntax
  4815 redeclaration.
  4816 
  4817 * Locale declaration: 'includes' disallowed.
  4818 
  4819 * Proper static binding of attribute syntax -- i.e. types / terms /
  4820 facts mentioned as arguments are always those of the locale definition
  4821 context, independently of the context of later invocations.  Moreover,
  4822 locale operations (renaming and type / term instantiation) are applied
  4823 to attribute arguments as expected.
  4824 
  4825 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4826 actual attributes; rare situations may require Attrib.attribute to
  4827 embed those attributes into Attrib.src that lack concrete syntax.
  4828 Attribute implementations need to cooperate properly with the static
  4829 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4830 Attrib.XXX_thm etc. already do the right thing without further
  4831 intervention.  Only unusual applications -- such as "where" or "of"
  4832 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4833 on the context and the facts involved -- may have to assign parsed
  4834 values to argument tokens explicitly.
  4835 
  4836 * Changed parameter management in theorem generation for long goal
  4837 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4838 theorem statement in rare situations.
  4839 
  4840 * Locale inspection command 'print_locale' omits notes elements.  Use
  4841 'print_locale!' to have them included in the output.
  4842 
  4843 
  4844 *** Provers ***
  4845 
  4846 * Provers/hypsubst.ML: improved version of the subst method, for
  4847 single-step rewriting: it now works in bound variable contexts. New is
  4848 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  4849 rewrite a different subterm than the original subst method, which is
  4850 still available as 'simplesubst'.
  4851 
  4852 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  4853 and quasi orders.
  4854 
  4855 * Provers/trancl.ML: new transitivity reasoner for transitive and
  4856 reflexive-transitive closure of relations.
  4857 
  4858 * Provers/blast.ML: new reference depth_limit to make blast's depth
  4859 limit (previously hard-coded with a value of 20) user-definable.
  4860 
  4861 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  4862 is peformed already.  Object-logics merely need to finish their
  4863 initial simpset configuration as before.  INCOMPATIBILITY.
  4864 
  4865 
  4866 *** HOL ***
  4867 
  4868 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  4869 
  4870   syntax (epsilon)
  4871     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  4872 
  4873 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  4874 and x-symbol; use option '-m epsilon' to get it actually printed.
  4875 Moreover, the mathematically important symbolic identifier \<epsilon>
  4876 becomes available as variable, constant etc.  INCOMPATIBILITY,
  4877 
  4878 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  4879 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  4880 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  4881 support corresponding Isar calculations.
  4882 
  4883 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  4884 instead of ":".
  4885 
  4886 * theory SetInterval: changed the syntax for open intervals:
  4887 
  4888   Old       New
  4889   {..n(}    {..<n}
  4890   {)n..}    {n<..}
  4891   {m..n(}   {m..<n}
  4892   {)m..n}   {m<..n}
  4893   {)m..n(}  {m<..<n}
  4894 
  4895 The old syntax is still supported but will disappear in the next
  4896 release.  For conversion use the following Emacs search and replace
  4897 patterns (these are not perfect but work quite well):
  4898 
  4899   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  4900   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  4901 
  4902 * Theory Commutative_Ring (in Library): method comm_ring for proving
  4903 equalities in commutative rings; method 'algebra' provides a generic
  4904 interface.
  4905 
  4906 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  4907 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  4908 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  4909 be a tuple pattern.
  4910 
  4911 Some new syntax forms are available:
  4912 
  4913   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  4914   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  4915   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  4916   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  4917 
  4918 The latter form "\<Sum>x < k. e" used to be based on a separate
  4919 function "Summation", which has been discontinued.
  4920 
  4921 * theory Finite_Set: in structured induction proofs, the insert case
  4922 is now 'case (insert x F)' instead of the old counterintuitive 'case
  4923 (insert F x)'.
  4924 
  4925 * The 'refute' command has been extended to support a much larger
  4926 fragment of HOL, including axiomatic type classes, constdefs and
  4927 typedefs, inductive datatypes and recursion.
  4928 
  4929 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  4930 Requires zChaff with proof generation to be installed.  See
  4931 HOL/ex/SAT_Examples.thy for examples.
  4932 
  4933 * Datatype induction via method 'induct' now preserves the name of the
  4934 induction variable. For example, when proving P(xs::'a list) by
  4935 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  4936 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  4937 in unstructured proof scripts.
  4938 
  4939 * Reworked implementation of records.  Improved scalability for
  4940 records with many fields, avoiding performance problems for type
  4941 inference. Records are no longer composed of nested field types, but
  4942 of nested extension types. Therefore the record type only grows linear
  4943 in the number of extensions and not in the number of fields.  The
  4944 top-level (users) view on records is preserved.  Potential
  4945 INCOMPATIBILITY only in strange cases, where the theory depends on the
  4946 old record representation. The type generated for a record is called
  4947 <record_name>_ext_type.
  4948 
  4949 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  4950 proofs triggered by a record definition or a simproc (if
  4951 quick_and_dirty is enabled).  Definitions of large records can take
  4952 quite long.
  4953 
  4954 New simproc record_upd_simproc for simplification of multiple record
  4955 updates enabled by default.  Moreover, trivial updates are also
  4956 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  4957 occasionally, since simplification is more powerful by default.
  4958 
  4959 * typedef: proper support for polymorphic sets, which contain extra
  4960 type-variables in the term.
  4961 
  4962 * Simplifier: automatically reasons about transitivity chains
  4963 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  4964 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  4965 old proofs break occasionally as simplification may now solve more
  4966 goals than previously.
  4967 
  4968 * Simplifier: converts x <= y into x = y if assumption y <= x is
  4969 present.  Works for all partial orders (class "order"), in particular
  4970 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  4971 just like y <= x.
  4972 
  4973 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  4974 bound variable or a constant then the let is unfolded.  Otherwise
  4975 first a is simplified to b, and then f b is simplified to g. If
  4976 possible we abstract b from g arriving at "let x = b in h x",
  4977 otherwise we unfold the let and arrive at g.  The simproc can be
  4978 enabled/disabled by the reference use_let_simproc.  Potential
  4979 INCOMPATIBILITY since simplification is more powerful by default.
  4980 
  4981 * Classical reasoning: the meson method now accepts theorems as arguments.
  4982 
  4983 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  4984 jobs to provide advice on the provability of subgoals.
  4985 
  4986 * Theory OrderedGroup and Ring_and_Field: various additions and
  4987 improvements to faciliate calculations involving equalities and
  4988 inequalities.
  4989 
  4990 The following theorems have been eliminated or modified
  4991 (INCOMPATIBILITY):
  4992 
  4993   abs_eq             now named abs_of_nonneg
  4994   abs_of_ge_0        now named abs_of_nonneg
  4995   abs_minus_eq       now named abs_of_nonpos
  4996   imp_abs_id         now named abs_of_nonneg
  4997   imp_abs_neg_id     now named abs_of_nonpos
  4998   mult_pos           now named mult_pos_pos
  4999   mult_pos_le        now named mult_nonneg_nonneg
  5000   mult_pos_neg_le    now named mult_nonneg_nonpos
  5001   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  5002   mult_neg           now named mult_neg_neg
  5003   mult_neg_le        now named mult_nonpos_nonpos
  5004 
  5005 * The following lemmas in Ring_and_Field have been added to the simplifier:
  5006      
  5007      zero_le_square
  5008      not_square_less_zero 
  5009 
  5010   The following lemmas have been deleted from Real/RealPow:
  5011   
  5012      realpow_zero_zero
  5013      realpow_two
  5014      realpow_less
  5015      zero_le_power
  5016      realpow_two_le
  5017      abs_realpow_two
  5018      realpow_two_abs     
  5019 
  5020 * Theory Parity: added rules for simplifying exponents.
  5021 
  5022 * Theory List:
  5023 
  5024 The following theorems have been eliminated or modified
  5025 (INCOMPATIBILITY):
  5026 
  5027   list_all_Nil       now named list_all.simps(1)
  5028   list_all_Cons      now named list_all.simps(2)
  5029   list_all_conv      now named list_all_iff
  5030   set_mem_eq         now named mem_iff
  5031 
  5032 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  5033 asymptotic "big O" calculations.  See the notes in BigO.thy.
  5034 
  5035 
  5036 *** HOL-Complex ***
  5037 
  5038 * Theory RealDef: better support for embedding natural numbers and
  5039 integers in the reals.
  5040 
  5041 The following theorems have been eliminated or modified
  5042 (INCOMPATIBILITY):
  5043 
  5044   exp_ge_add_one_self  now requires no hypotheses
  5045   real_of_int_add      reversed direction of equality (use [symmetric])
  5046   real_of_int_minus    reversed direction of equality (use [symmetric])
  5047   real_of_int_diff     reversed direction of equality (use [symmetric])
  5048   real_of_int_mult     reversed direction of equality (use [symmetric])
  5049 
  5050 * Theory RComplete: expanded support for floor and ceiling functions.
  5051 
  5052 * Theory Ln is new, with properties of the natural logarithm
  5053 
  5054 * Hyperreal: There is a new type constructor "star" for making
  5055 nonstandard types.  The old type names are now type synonyms:
  5056 
  5057   hypreal = real star
  5058   hypnat = nat star
  5059   hcomplex = complex star
  5060 
  5061 * Hyperreal: Many groups of similarly-defined constants have been
  5062 replaced by polymorphic versions (INCOMPATIBILITY):
  5063 
  5064   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  5065 
  5066   starset      <-- starsetNat, starsetC
  5067   *s*          <-- *sNat*, *sc*
  5068   starset_n    <-- starsetNat_n, starsetC_n
  5069   *sn*         <-- *sNatn*, *scn*
  5070   InternalSets <-- InternalNatSets, InternalCSets
  5071 
  5072   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  5073   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  5074   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  5075   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  5076   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  5077 
  5078 * Hyperreal: Many type-specific theorems have been removed in favor of
  5079 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  5080 
  5081   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  5082   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  5083   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  5084   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  5085   right_minus <-- hypreal_add_minus
  5086   left_minus <-- {hypreal,hcomplex}_add_minus_left
  5087   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  5088   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  5089   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  5090   mult_1_right <-- hcomplex_mult_one_right
  5091   mult_zero_left <-- hcomplex_mult_zero_left
  5092   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  5093   right_distrib <-- hypnat_add_mult_distrib2
  5094   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  5095   right_inverse <-- hypreal_mult_inverse
  5096   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  5097   order_refl <-- {hypreal,hypnat}_le_refl
  5098   order_trans <-- {hypreal,hypnat}_le_trans
  5099   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  5100   order_less_le <-- {hypreal,hypnat}_less_le
  5101   linorder_linear <-- {hypreal,hypnat}_le_linear
  5102   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  5103   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  5104   add_nonneg_nonneg <-- hypreal_le_add_order
  5105 
  5106 * Hyperreal: Separate theorems having to do with type-specific
  5107 versions of constants have been merged into theorems that apply to the
  5108 new polymorphic constants (INCOMPATIBILITY):
  5109 
  5110   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  5111   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  5112   STAR_Un <-- {STAR,NatStar,STARC}_Un
  5113   STAR_Int <-- {STAR,NatStar,STARC}_Int
  5114   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  5115   STAR_subset <-- {STAR,NatStar,STARC}_subset
  5116   STAR_mem <-- {STAR,NatStar,STARC}_mem
  5117   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  5118   STAR_diff <-- {STAR,STARC}_diff
  5119   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  5120     STARC_hcomplex_of_complex}_image_subset
  5121   starset_n_Un <-- starset{Nat,C}_n_Un
  5122   starset_n_Int <-- starset{Nat,C}_n_Int
  5123   starset_n_Compl <-- starset{Nat,C}_n_Compl
  5124   starset_n_diff <-- starset{Nat,C}_n_diff
  5125   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  5126   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  5127   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  5128   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  5129   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  5130   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  5131   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  5132   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  5133   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  5134   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  5135   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  5136   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  5137   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  5138   starfun_diff <-- starfun{C,RC,CR}_diff
  5139   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  5140   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  5141   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  5142   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  5143   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  5144   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  5145   starfun_Id <-- starfunC_Id
  5146   starfun_approx <-- starfun{Nat,CR}_approx
  5147   starfun_capprox <-- starfun{C,RC}_capprox
  5148   starfun_abs <-- starfunNat_rabs
  5149   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  5150   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  5151   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  5152   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  5153   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  5154   starfun_add_approx <-- starfunCR_add_approx
  5155   starfun_inverse_inverse <-- starfunC_inverse_inverse
  5156   starfun_divide <-- starfun{C,CR,RC}_divide
  5157   starfun_n <-- starfun{Nat,C}_n
  5158   starfun_n_mult <-- starfun{Nat,C}_n_mult
  5159   starfun_n_add <-- starfun{Nat,C}_n_add
  5160   starfun_n_add_minus <-- starfunNat_n_add_minus
  5161   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  5162   starfun_n_minus <-- starfun{Nat,C}_n_minus
  5163   starfun_n_eq <-- starfun{Nat,C}_n_eq
  5164 
  5165   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  5166   star_n_minus <-- {hypreal,hcomplex}_minus
  5167   star_n_diff <-- {hypreal,hcomplex}_diff
  5168   star_n_mult <-- {hypreal,hcomplex}_mult
  5169   star_n_inverse <-- {hypreal,hcomplex}_inverse
  5170   star_n_le <-- {hypreal,hypnat}_le
  5171   star_n_less <-- {hypreal,hypnat}_less
  5172   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  5173   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  5174   star_n_abs <-- hypreal_hrabs
  5175   star_n_divide <-- hcomplex_divide
  5176 
  5177   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  5178   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  5179   star_of_diff <-- hypreal_of_real_diff
  5180   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  5181   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  5182   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  5183   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  5184   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  5185   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  5186   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  5187   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  5188   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  5189   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  5190   star_of_number_of <-- {hypreal,hcomplex}_number_of
  5191   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  5192   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  5193   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  5194   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  5195   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  5196   star_of_power <-- hypreal_of_real_power
  5197   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  5198 
  5199 * Hyperreal: new method "transfer" that implements the transfer
  5200 principle of nonstandard analysis. With a subgoal that mentions
  5201 nonstandard types like "'a star", the command "apply transfer"
  5202 replaces it with an equivalent one that mentions only standard types.
  5203 To be successful, all free variables must have standard types; non-
  5204 standard variables must have explicit universal quantifiers.
  5205 
  5206 * Hyperreal: A theory of Taylor series.
  5207 
  5208 
  5209 *** HOLCF ***
  5210 
  5211 * Discontinued special version of 'constdefs' (which used to support
  5212 continuous functions) in favor of the general Pure one with full
  5213 type-inference.
  5214 
  5215 * New simplification procedure for solving continuity conditions; it
  5216 is much faster on terms with many nested lambda abstractions (cubic
  5217 instead of exponential time).
  5218 
  5219 * New syntax for domain package: selector names are now optional.
  5220 Parentheses should be omitted unless argument is lazy, for example:
  5221 
  5222   domain 'a stream = cons "'a" (lazy "'a stream")
  5223 
  5224 * New command 'fixrec' for defining recursive functions with pattern
  5225 matching; defining multiple functions with mutual recursion is also
  5226 supported.  Patterns may include the constants cpair, spair, up, sinl,
  5227 sinr, or any data constructor defined by the domain package. The given
  5228 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  5229 syntax and examples.
  5230 
  5231 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  5232 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  5233 but the proof obligation additionally includes an admissibility
  5234 requirement. The packages generate instances of class cpo or pcpo,
  5235 with continuity and strictness theorems for Rep and Abs.
  5236 
  5237 * HOLCF: Many theorems have been renamed according to a more standard naming
  5238 scheme (INCOMPATIBILITY):
  5239 
  5240   foo_inject:  "foo$x = foo$y ==> x = y"
  5241   foo_eq:      "(foo$x = foo$y) = (x = y)"
  5242   foo_less:    "(foo$x << foo$y) = (x << y)"
  5243   foo_strict:  "foo$UU = UU"
  5244   foo_defined: "... ==> foo$x ~= UU"
  5245   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  5246 
  5247 
  5248 *** ZF ***
  5249 
  5250 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  5251 including the First Isomorphism Theorem (on quotienting by the kernel
  5252 of a homomorphism).
  5253 
  5254 * ZF/Simplifier: install second copy of type solver that actually
  5255 makes use of TC rules declared to Isar proof contexts (or locales);
  5256 the old version is still required for ML proof scripts.
  5257 
  5258 
  5259 *** Cube ***
  5260 
  5261 * Converted to Isar theory format; use locales instead of axiomatic
  5262 theories.
  5263 
  5264 
  5265 *** ML ***
  5266 
  5267 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  5268 for ||>, ||>>, |>>,
  5269 
  5270 * Pure/library.ML no longer defines its own option datatype, but uses
  5271 that of the SML basis, which has constructors NONE and SOME instead of
  5272 None and Some, as well as exception Option.Option instead of OPTION.
  5273 The functions the, if_none, is_some, is_none have been adapted
  5274 accordingly, while Option.map replaces apsome.
  5275 
  5276 * Pure/library.ML: the exception LIST has been given up in favour of
  5277 the standard exceptions Empty and Subscript, as well as
  5278 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  5279 superceded by the standard hd and tl functions etc.
  5280 
  5281 A number of basic list functions are no longer exported to the ML
  5282 toplevel, as they are variants of predefined functions.  The following
  5283 suggests how one can translate existing code:
  5284 
  5285     rev_append xs ys = List.revAppend (xs, ys)
  5286     nth_elem (i, xs) = List.nth (xs, i)
  5287     last_elem xs = List.last xs
  5288     flat xss = List.concat xss
  5289     seq fs = List.app fs
  5290     partition P xs = List.partition P xs
  5291     mapfilter f xs = List.mapPartial f xs
  5292 
  5293 * Pure/library.ML: several combinators for linear functional
  5294 transformations, notably reverse application and composition:
  5295 
  5296   x |> f                f #> g
  5297   (x, y) |-> f          f #-> g
  5298 
  5299 * Pure/library.ML: introduced/changed precedence of infix operators:
  5300 
  5301   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  5302   infix 2 ?;
  5303   infix 3 o oo ooo oooo;
  5304   infix 4 ~~ upto downto;
  5305 
  5306 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  5307 infix operators.
  5308 
  5309 * Pure/library.ML: natural list combinators fold, fold_rev, and
  5310 fold_map support linear functional transformations and nesting.  For
  5311 example:
  5312 
  5313   fold f [x1, ..., xN] y =
  5314     y |> f x1 |> ... |> f xN
  5315 
  5316   (fold o fold) f [xs1, ..., xsN] y =
  5317     y |> fold f xs1 |> ... |> fold f xsN
  5318 
  5319   fold f [x1, ..., xN] =
  5320     f x1 #> ... #> f xN
  5321 
  5322   (fold o fold) f [xs1, ..., xsN] =
  5323     fold f xs1 #> ... #> fold f xsN
  5324 
  5325 * Pure/library.ML: the following selectors on type 'a option are
  5326 available:
  5327 
  5328   the:               'a option -> 'a  (*partial*)
  5329   these:             'a option -> 'a  where 'a = 'b list
  5330   the_default: 'a -> 'a option -> 'a
  5331   the_list:          'a option -> 'a list
  5332 
  5333 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5334 basic operations for association lists, following natural argument
  5335 order; moreover the explicit equality predicate passed here avoids
  5336 potentially expensive polymorphic runtime equality checks.
  5337 The old functions may be expressed as follows:
  5338 
  5339   assoc = uncurry (AList.lookup (op =))
  5340   assocs = these oo AList.lookup (op =)
  5341   overwrite = uncurry (AList.update (op =)) o swap
  5342 
  5343 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5344 
  5345   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  5346   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  5347 
  5348 replacing make_keylist and keyfilter (occassionally used)
  5349 Naive rewrites:
  5350 
  5351   make_keylist = AList.make
  5352   keyfilter = AList.find (op =)
  5353 
  5354 * eq_fst and eq_snd now take explicit equality parameter, thus
  5355   avoiding eqtypes. Naive rewrites:
  5356 
  5357     eq_fst = eq_fst (op =)
  5358     eq_snd = eq_snd (op =)
  5359 
  5360 * Removed deprecated apl and apr (rarely used).
  5361   Naive rewrites:
  5362 
  5363     apl (n, op) =>>= curry op n
  5364     apr (op, m) =>>= fn n => op (n, m)
  5365 
  5366 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  5367 provides a reasonably efficient light-weight implementation of sets as
  5368 lists.
  5369 
  5370 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  5371 few new operations; existing lookup and update are now curried to
  5372 follow natural argument order (for use with fold etc.);
  5373 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  5374 
  5375 * Pure/General: output via the Isabelle channels of
  5376 writeln/warning/error etc. is now passed through Output.output, with a
  5377 hook for arbitrary transformations depending on the print_mode
  5378 (cf. Output.add_mode -- the first active mode that provides a output
  5379 function wins).  Already formatted output may be embedded into further
  5380 text via Output.raw; the result of Pretty.string_of/str_of and derived
  5381 functions (string_of_term/cterm/thm etc.) is already marked raw to
  5382 accommodate easy composition of diagnostic messages etc.  Programmers
  5383 rarely need to care about Output.output or Output.raw at all, with
  5384 some notable exceptions: Output.output is required when bypassing the
  5385 standard channels (writeln etc.), or in token translations to produce
  5386 properly formatted results; Output.raw is required when capturing
  5387 already output material that will eventually be presented to the user
  5388 a second time.  For the default print mode, both Output.output and
  5389 Output.raw have no effect.
  5390 
  5391 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  5392 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  5393 cumulative results are displayed at the end of a batch session.
  5394 
  5395 * Pure/General: File.sysify_path and File.quote_sysify path have been
  5396 replaced by File.platform_path and File.shell_path (with appropriate
  5397 hooks).  This provides a clean interface for unusual systems where the
  5398 internal and external process view of file names are different.
  5399 
  5400 * Pure: more efficient orders for basic syntactic entities: added
  5401 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  5402 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  5403 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  5404 orders now -- potential INCOMPATIBILITY for code that depends on a
  5405 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  5406 Library.sort_strings on result).
  5407 
  5408 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  5409 fold_types traverse types/terms from left to right, observing natural
  5410 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  5411 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  5412 
  5413 * Pure: name spaces have been refined, with significant changes of the
  5414 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  5415 to extern(_table).  The plain name entry path is superceded by a
  5416 general 'naming' context, which also includes the 'policy' to produce
  5417 a fully qualified name and external accesses of a fully qualified
  5418 name; NameSpace.extend is superceded by context dependent
  5419 Sign.declare_name.  Several theory and proof context operations modify
  5420 the naming context.  Especially note Theory.restore_naming and
  5421 ProofContext.restore_naming to get back to a sane state; note that
  5422 Theory.add_path is no longer sufficient to recover from
  5423 Theory.absolute_path in particular.
  5424 
  5425 * Pure: new flags short_names (default false) and unique_names
  5426 (default true) for controlling output of qualified names.  If
  5427 short_names is set, names are printed unqualified.  If unique_names is
  5428 reset, the name prefix is reduced to the minimum required to achieve
  5429 the original result when interning again, even if there is an overlap
  5430 with earlier declarations.
  5431 
  5432 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  5433 now 'extend', and 'merge' gets an additional Pretty.pp argument
  5434 (useful for printing error messages).  INCOMPATIBILITY.
  5435 
  5436 * Pure: major reorganization of the theory context.  Type Sign.sg and
  5437 Theory.theory are now identified, referring to the universal
  5438 Context.theory (see Pure/context.ML).  Actual signature and theory
  5439 content is managed as theory data.  The old code and interfaces were
  5440 spread over many files and structures; the new arrangement introduces
  5441 considerable INCOMPATIBILITY to gain more clarity:
  5442 
  5443   Context -- theory management operations (name, identity, inclusion,
  5444     parents, ancestors, merge, etc.), plus generic theory data;
  5445 
  5446   Sign -- logical signature and syntax operations (declaring consts,
  5447     types, etc.), plus certify/read for common entities;
  5448 
  5449   Theory -- logical theory operations (stating axioms, definitions,
  5450     oracles), plus a copy of logical signature operations (consts,
  5451     types, etc.); also a few basic management operations (Theory.copy,
  5452     Theory.merge, etc.)
  5453 
  5454 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  5455 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  5456 for convenience -- they merely return the theory.
  5457 
  5458 * Pure: type Type.tsig is superceded by theory in most interfaces.
  5459 
  5460 * Pure: the Isar proof context type is already defined early in Pure
  5461 as Context.proof (note that ProofContext.context and Proof.context are
  5462 aliases, where the latter is the preferred name).  This enables other
  5463 Isabelle components to refer to that type even before Isar is present.
  5464 
  5465 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  5466 typeK, constK, axiomK, oracleK), but provide explicit operations for
  5467 any of these kinds.  For example, Sign.intern typeK is now
  5468 Sign.intern_type, Theory.hide_space Sign.typeK is now
  5469 Theory.hide_types.  Also note that former
  5470 Theory.hide_classes/types/consts are now
  5471 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  5472 internalize their arguments!  INCOMPATIBILITY.
  5473 
  5474 * Pure: get_thm interface (of PureThy and ProofContext) expects
  5475 datatype thmref (with constructors Name and NameSelection) instead of
  5476 plain string -- INCOMPATIBILITY;
  5477 
  5478 * Pure: cases produced by proof methods specify options, where NONE
  5479 means to remove case bindings -- INCOMPATIBILITY in
  5480 (RAW_)METHOD_CASES.
  5481 
  5482 * Pure: the following operations retrieve axioms or theorems from a
  5483 theory node or theory hierarchy, respectively:
  5484 
  5485   Theory.axioms_of: theory -> (string * term) list
  5486   Theory.all_axioms_of: theory -> (string * term) list
  5487   PureThy.thms_of: theory -> (string * thm) list
  5488   PureThy.all_thms_of: theory -> (string * thm) list
  5489 
  5490 * Pure: print_tac now outputs the goal through the trace channel.
  5491 
  5492 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  5493 Reference Toplevel.debug (default false) controls detailed printing
  5494 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  5495 controls execution profiling -- set to 1 for time and 2 for space
  5496 (both increase the runtime).
  5497 
  5498 * Isar session: The initial use of ROOT.ML is now always timed,
  5499 i.e. the log will show the actual process times, in contrast to the
  5500 elapsed wall-clock time that the outer shell wrapper produces.
  5501 
  5502 * Simplifier: improved handling of bound variables (nameless
  5503 representation, avoid allocating new strings).  Simprocs that invoke
  5504 the Simplifier recursively should use Simplifier.inherit_bounds to
  5505 avoid local name clashes.  Failure to do so produces warnings
  5506 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  5507 for further details.
  5508 
  5509 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  5510 bindings for all theorems stored within a given theory; this may help
  5511 in porting non-Isar theories to Isar ones, while keeping ML proof
  5512 scripts for the time being.
  5513 
  5514 * ML operator HTML.with_charset specifies the charset begin used for
  5515 generated HTML files.  For example:
  5516 
  5517   HTML.with_charset "utf-8" use_thy "Hebrew";
  5518   HTML.with_charset "utf-8" use_thy "Chinese";
  5519 
  5520 
  5521 *** System ***
  5522 
  5523 * Allow symlinks to all proper Isabelle executables (Isabelle,
  5524 isabelle, isatool etc.).
  5525 
  5526 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  5527 isatool doc, isatool mkdir, display_drafts etc.).
  5528 
  5529 * isatool usedir: option -f allows specification of the ML file to be
  5530 used by Isabelle; default is ROOT.ML.
  5531 
  5532 * New isatool version outputs the version identifier of the Isabelle
  5533 distribution being used.
  5534 
  5535 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  5536 (containing Boolean satisfiability problems) into Isabelle/HOL
  5537 theories.
  5538 
  5539 
  5540 
  5541 New in Isabelle2004 (April 2004)
  5542 --------------------------------
  5543 
  5544 *** General ***
  5545 
  5546 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  5547   Replaces linorder.ML.
  5548 
  5549 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  5550   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  5551   (\<a>...\<z>), are now considered normal letters, and can therefore
  5552   be used anywhere where an ASCII letter (a...zA...Z) has until
  5553   now. COMPATIBILITY: This obviously changes the parsing of some
  5554   terms, especially where a symbol has been used as a binder, say
  5555   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  5556   as an identifier.  Fix it by inserting a space around former
  5557   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  5558   existing theory and ML files.
  5559 
  5560 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  5561 
  5562 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  5563   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  5564   a normal (but invisible) letter. For multiple letter subscripts repeat
  5565   \<^isub> like this: x\<^isub>1\<^isub>2.
  5566 
  5567 * Pure: There are now sub-/superscripts that can span more than one
  5568   character. Text between \<^bsub> and \<^esub> is set in subscript in
  5569   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  5570   superscript. The new control characters are not identifier parts.
  5571 
  5572 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5573   content of "..." to the latex file instead of \isacntrl... . The "..."
  5574   may consist of any printable characters excluding the end bracket >.
  5575 
  5576 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5577   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5578   declare constants "final", which prevents their being given a definition
  5579   later.  It is useful for constants whose behaviour is fixed axiomatically
  5580   rather than definitionally, such as the meta-logic connectives.
  5581 
  5582 * Pure: 'instance' now handles general arities with general sorts
  5583   (i.e. intersections of classes),
  5584 
  5585 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5586   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5587   It can be changed to alter the colors/layout of generated pages.
  5588 
  5589 
  5590 *** Isar ***
  5591 
  5592 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5593   cut_tac, subgoal_tac and thin_tac:
  5594   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5595     locales are no longer forced to write Isar proof scripts.
  5596     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5597     emulations.
  5598   - INCOMPATIBILITY: names of variables to be instantiated may no
  5599     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5600     This is consistent with the instantiation attribute "where".
  5601 
  5602 * Attributes "where" and "of":
  5603   - Now take type variables of instantiated theorem into account when reading
  5604     the instantiation string.  This fixes a bug that caused instantiated
  5605     theorems to have too special types in some circumstances.
  5606   - "where" permits explicit instantiations of type variables.
  5607 
  5608 * Calculation commands "moreover" and "also" no longer interfere with
  5609   current facts ("this"), admitting arbitrary combinations with "then"
  5610   and derived forms.
  5611 
  5612 * Locales:
  5613   - Goal statements involving the context element "includes" no longer
  5614     generate theorems with internal delta predicates (those ending on
  5615     "_axioms") in the premise.
  5616     Resolve particular premise with <locale>.intro to obtain old form.
  5617   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5618     specification and "includes" elements in goal statement.
  5619   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5620     [intro?] and [elim?] (respectively) by default.
  5621   - Experimental command for instantiation of locales in proof contexts:
  5622         instantiate <label>[<attrs>]: <loc>
  5623     Instantiates locale <loc> and adds all its theorems to the current context
  5624     taking into account their attributes.  Label and attrs are optional
  5625     modifiers, like in theorem declarations.  If present, names of
  5626     instantiated theorems are qualified with <label>, and the attributes
  5627     <attrs> are applied after any attributes these theorems might have already.
  5628       If the locale has assumptions, a chained fact of the form
  5629     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5630     are derived.  The command does not support old-style locales declared
  5631     with "locale (open)".
  5632       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5633 
  5634 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5635   (Isar) contexts.
  5636 
  5637 
  5638 *** HOL ***
  5639 
  5640 * Proof import: new image HOL4 contains the imported library from
  5641   the HOL4 system with about 2500 theorems. It is imported by
  5642   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5643   can be used like any other Isabelle image.  See
  5644   HOL/Import/HOL/README for more information.
  5645 
  5646 * Simplifier:
  5647   - Much improved handling of linear and partial orders.
  5648     Reasoners for linear and partial orders are set up for type classes
  5649     "linorder" and "order" respectively, and are added to the default simpset
  5650     as solvers.  This means that the simplifier can build transitivity chains
  5651     to solve goals from the assumptions.
  5652   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5653     of blast or auto after simplification become unnecessary because the goal
  5654     is solved by simplification already.
  5655 
  5656 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5657     all proved in axiomatic type classes for semirings, rings and fields.
  5658 
  5659 * Numerics:
  5660   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5661     now formalized using the Ring_and_Field theory mentioned above.
  5662   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5663     than before, because now they are set up once in a generic manner.
  5664   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5665     Look for the general versions in Ring_and_Field (and Power if they concern
  5666     exponentiation).
  5667 
  5668 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5669 
  5670 * Records:
  5671   - Record types are now by default printed with their type abbreviation
  5672     instead of the list of all field types. This can be configured via
  5673     the reference "print_record_type_abbr".
  5674   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5675     (not enabled by default).
  5676   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5677     EX x. x = sel r to True (not enabled by default).
  5678   - Tactic "record_split_simp_tac" to split and simplify records added.
  5679 
  5680 * 'specification' command added, allowing for definition by
  5681   specification.  There is also an 'ax_specification' command that
  5682   introduces the new constants axiomatically.
  5683 
  5684 * arith(_tac) is now able to generate counterexamples for reals as well.
  5685 
  5686 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5687 
  5688 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5689   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5690 
  5691 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5692   matrix theory to linear programming.
  5693 
  5694 * Unions and Intersections:
  5695   The latex output syntax of UN and INT has been changed
  5696   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5697   i.e. the index formulae has become a subscript.
  5698   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5699 
  5700 * Unions and Intersections over Intervals:
  5701   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5702   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5703   like in normal math, and corresponding versions for < and for intersection.
  5704 
  5705 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5706   lexicographic dictonary ordering has been added as "lexord".
  5707 
  5708 * ML: the legacy theory structures Int and List have been removed. They had
  5709   conflicted with ML Basis Library structures having the same names.
  5710 
  5711 * 'refute' command added to search for (finite) countermodels.  Only works
  5712   for a fragment of HOL.  The installation of an external SAT solver is
  5713   highly recommended.  See "HOL/Refute.thy" for details.
  5714 
  5715 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5716   formulae under an assignment of free variables to random values.
  5717   In contrast to 'refute', it can deal with inductive datatypes,
  5718   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5719   for examples.
  5720 
  5721 
  5722 *** HOLCF ***
  5723 
  5724 * Streams now come with concatenation and are part of the HOLCF image
  5725 
  5726 
  5727 
  5728 New in Isabelle2003 (May 2003)
  5729 ------------------------------
  5730 
  5731 *** General ***
  5732 
  5733 * Provers/simplifier:
  5734 
  5735   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5736     Assumptions are now subject to complete mutual simplification,
  5737     not just from left to right. The simplifier now preserves
  5738     the order of assumptions.
  5739 
  5740     Potential INCOMPATIBILITY:
  5741 
  5742     -- simp sometimes diverges where the old version did
  5743        not, e.g. invoking simp on the goal
  5744 
  5745         [| P (f x); y = x; f x = f y |] ==> Q
  5746 
  5747        now gives rise to the infinite reduction sequence
  5748 
  5749         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5750 
  5751        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5752        kind of problem.
  5753 
  5754     -- Tactics combining classical reasoner and simplification (such as auto)
  5755        are also affected by this change, because many of them rely on
  5756        simp. They may sometimes diverge as well or yield a different numbers
  5757        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5758        in case of problems. Sometimes subsequent calls to the classical
  5759        reasoner will fail because a preceeding call to the simplifier too
  5760        eagerly simplified the goal, e.g. deleted redundant premises.
  5761 
  5762   - The simplifier trace now shows the names of the applied rewrite rules
  5763 
  5764   - You can limit the number of recursive invocations of the simplifier
  5765     during conditional rewriting (where the simplifie tries to solve the
  5766     conditions before applying the rewrite rule):
  5767     ML "simp_depth_limit := n"
  5768     where n is an integer. Thus you can force termination where previously
  5769     the simplifier would diverge.
  5770 
  5771   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5772 
  5773   - No longer aborts on failed congruence proof.  Instead, the
  5774     congruence is ignored.
  5775 
  5776 * Pure: New generic framework for extracting programs from constructive
  5777   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5778   as HOL/Extraction for some case studies.
  5779 
  5780 * Pure: The main goal of the proof state is no longer shown by default, only
  5781 the subgoals. This behaviour is controlled by a new flag.
  5782    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5783 (ML: Proof.show_main_goal).
  5784 
  5785 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5786 rules whose conclusion matches subgoal 1:
  5787       PG menu: Isabelle/Isar -> Show me -> matching rules
  5788 The rules are ordered by how closely they match the subgoal.
  5789 In particular, rules that solve a subgoal outright are displayed first
  5790 (or rather last, the way they are printed).
  5791 (ML: ProofGeneral.print_intros())
  5792 
  5793 * Pure: New flag trace_unify_fail causes unification to print
  5794 diagnostic information (PG: in trace buffer) when it fails. This is
  5795 useful for figuring out why single step proofs like rule, erule or
  5796 assumption failed.
  5797 
  5798 * Pure: Locale specifications now produce predicate definitions
  5799 according to the body of text (covering assumptions modulo local
  5800 definitions); predicate "loc_axioms" covers newly introduced text,
  5801 while "loc" is cumulative wrt. all included locale expressions; the
  5802 latter view is presented only on export into the global theory
  5803 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5804 on the old view without predicates;
  5805 
  5806 * Pure: predefined locales "var" and "struct" are useful for sharing
  5807 parameters (as in CASL, for example); just specify something like
  5808 ``var x + var y + struct M'' as import;
  5809 
  5810 * Pure: improved thms_containing: proper indexing of facts instead of
  5811 raw theorems; check validity of results wrt. current name space;
  5812 include local facts of proof configuration (also covers active
  5813 locales), cover fixed variables in index; may use "_" in term
  5814 specification; an optional limit for the number of printed facts may
  5815 be given (the default is 40);
  5816 
  5817 * Pure: disallow duplicate fact bindings within new-style theory files
  5818 (batch-mode only);
  5819 
  5820 * Provers: improved induct method: assumptions introduced by case
  5821 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5822 the goal statement); "foo" still refers to all facts collectively;
  5823 
  5824 * Provers: the function blast.overloaded has been removed: all constants
  5825 are regarded as potentially overloaded, which improves robustness in exchange
  5826 for slight decrease in efficiency;
  5827 
  5828 * Provers/linorder: New generic prover for transitivity reasoning over
  5829 linear orders.  Note: this prover is not efficient!
  5830 
  5831 * Isar: preview of problems to finish 'show' now produce an error
  5832 rather than just a warning (in interactive mode);
  5833 
  5834 
  5835 *** HOL ***
  5836 
  5837 * arith(_tac)
  5838 
  5839  - Produces a counter example if it cannot prove a goal.
  5840    Note that the counter example may be spurious if the goal is not a formula
  5841    of quantifier-free linear arithmetic.
  5842    In ProofGeneral the counter example appears in the trace buffer.
  5843 
  5844  - Knows about div k and mod k where k is a numeral of type nat or int.
  5845 
  5846  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  5847    linear arithmetic fails. This takes account of quantifiers and divisibility.
  5848    Presburger arithmetic can also be called explicitly via presburger(_tac).
  5849 
  5850 * simp's arithmetic capabilities have been enhanced a bit: it now
  5851 takes ~= in premises into account (by performing a case split);
  5852 
  5853 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  5854 are distributed over a sum of terms;
  5855 
  5856 * New tactic "trans_tac" and method "trans" instantiate
  5857 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  5858 "<=", "<" and "=").
  5859 
  5860 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  5861 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  5862 
  5863 * 'typedef' command has new option "open" to suppress the set
  5864 definition;
  5865 
  5866 * functions Min and Max on finite sets have been introduced (theory
  5867 Finite_Set);
  5868 
  5869 * attribute [symmetric] now works for relations as well; it turns
  5870 (x,y) : R^-1 into (y,x) : R, and vice versa;
  5871 
  5872 * induct over a !!-quantified statement (say !!x1..xn):
  5873   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  5874 
  5875 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  5876 %x. None. Warning: empty_def now refers to the previously hidden definition
  5877 of the empty set.
  5878 
  5879 * Algebra: formalization of classical algebra.  Intended as base for
  5880 any algebraic development in Isabelle.  Currently covers group theory
  5881 (up to Sylow's theorem) and ring theory (Universal Property of
  5882 Univariate Polynomials).  Contributions welcome;
  5883 
  5884 * GroupTheory: deleted, since its material has been moved to Algebra;
  5885 
  5886 * Complex: new directory of the complex numbers with numeric constants,
  5887 nonstandard complex numbers, and some complex analysis, standard and
  5888 nonstandard (Jacques Fleuriot);
  5889 
  5890 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  5891 
  5892 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  5893 Fleuriot);
  5894 
  5895 * Real/HahnBanach: updated and adapted to locales;
  5896 
  5897 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  5898 Gray and Kramer);
  5899 
  5900 * UNITY: added the Meier-Sanders theory of progress sets;
  5901 
  5902 * MicroJava: bytecode verifier and lightweight bytecode verifier
  5903 as abstract algorithms, instantiated to the JVM;
  5904 
  5905 * Bali: Java source language formalization. Type system, operational
  5906 semantics, axiomatic semantics. Supported language features:
  5907 classes, interfaces, objects,virtual methods, static methods,
  5908 static/instance fields, arrays, access modifiers, definite
  5909 assignment, exceptions.
  5910 
  5911 
  5912 *** ZF ***
  5913 
  5914 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  5915 universe, etc.);
  5916 
  5917 * Main ZF: virtually all theories converted to new-style format;
  5918 
  5919 
  5920 *** ML ***
  5921 
  5922 * Pure: Tactic.prove provides sane interface for internal proofs;
  5923 omits the infamous "standard" operation, so this is more appropriate
  5924 than prove_goalw_cterm in many situations (e.g. in simprocs);
  5925 
  5926 * Pure: improved error reporting of simprocs;
  5927 
  5928 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  5929 up simprocs;
  5930 
  5931 
  5932 *** Document preparation ***
  5933 
  5934 * uses \par instead of \\ for line breaks in theory text. This may
  5935 shift some page breaks in large documents. To get the old behaviour
  5936 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  5937 
  5938 * minimized dependencies of isabelle.sty and isabellesym.sty on
  5939 other packages
  5940 
  5941 * \<euro> now needs package babel/greek instead of marvosym (which
  5942 broke \Rightarrow)
  5943 
  5944 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  5945 textcomp package)
  5946 
  5947 
  5948 
  5949 New in Isabelle2002 (March 2002)
  5950 --------------------------------
  5951 
  5952 *** Document preparation ***
  5953 
  5954 * greatly simplified document preparation setup, including more
  5955 graceful interpretation of isatool usedir -i/-d/-D options, and more
  5956 instructive isatool mkdir; users should basically be able to get
  5957 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  5958 users may run a separate document processing stage manually like this:
  5959 "isatool usedir -D output HOL Test && isatool document Test/output";
  5960 
  5961 * theory dependency graph may now be incorporated into documents;
  5962 isatool usedir -g true will produce session_graph.eps/.pdf for use
  5963 with \includegraphics of LaTeX;
  5964 
  5965 * proper spacing of consecutive markup elements, especially text
  5966 blocks after section headings;
  5967 
  5968 * support bold style (for single symbols only), input syntax is like
  5969 this: "\<^bold>\<alpha>" or "\<^bold>A";
  5970 
  5971 * \<bullet> is now output as bold \cdot by default, which looks much
  5972 better in printed text;
  5973 
  5974 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  5975 note that these symbols are currently unavailable in Proof General /
  5976 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  5977 
  5978 * isatool latex no longer depends on changed TEXINPUTS, instead
  5979 isatool document copies the Isabelle style files to the target
  5980 location;
  5981 
  5982 
  5983 *** Isar ***
  5984 
  5985 * Pure/Provers: improved proof by cases and induction;
  5986   - 'case' command admits impromptu naming of parameters (such as
  5987     "case (Suc n)");
  5988   - 'induct' method divinates rule instantiation from the inductive
  5989     claim; no longer requires excessive ?P bindings for proper
  5990     instantiation of cases;
  5991   - 'induct' method properly enumerates all possibilities of set/type
  5992     rules; as a consequence facts may be also passed through *type*
  5993     rules without further ado;
  5994   - 'induct' method now derives symbolic cases from the *rulified*
  5995     rule (before it used to rulify cases stemming from the internal
  5996     atomized version); this means that the context of a non-atomic
  5997     statement becomes is included in the hypothesis, avoiding the
  5998     slightly cumbersome show "PROP ?case" form;
  5999   - 'induct' may now use elim-style induction rules without chaining
  6000     facts, using ``missing'' premises from the goal state; this allows
  6001     rules stemming from inductive sets to be applied in unstructured
  6002     scripts, while still benefitting from proper handling of non-atomic
  6003     statements; NB: major inductive premises need to be put first, all
  6004     the rest of the goal is passed through the induction;
  6005   - 'induct' proper support for mutual induction involving non-atomic
  6006     rule statements (uses the new concept of simultaneous goals, see
  6007     below);
  6008   - append all possible rule selections, but only use the first
  6009     success (no backtracking);
  6010   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  6011   - undeclared rule case names default to numbers 1, 2, 3, ...;
  6012   - added 'print_induct_rules' (covered by help item in recent Proof
  6013     General versions);
  6014   - moved induct/cases attributes to Pure, methods to Provers;
  6015   - generic method setup instantiated for FOL and HOL;
  6016 
  6017 * Pure: support multiple simultaneous goal statements, for example
  6018 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  6019 meta-level mechanism, this acts as if several individual goals had
  6020 been stated separately; in particular common proof methods need to be
  6021 repeated in order to cover all claims; note that a single elimination
  6022 step is *not* sufficient to establish the two conjunctions, so this
  6023 fails:
  6024 
  6025   assume "A & B" then have A and B ..   (*".." fails*)
  6026 
  6027 better use "obtain" in situations as above; alternative refer to
  6028 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  6029 
  6030 * Pure: proper integration with ``locales''; unlike the original
  6031 version by Florian Kammller, Isar locales package high-level proof
  6032 contexts rather than raw logical ones (e.g. we admit to include
  6033 attributes everywhere); operations on locales include merge and
  6034 rename; support for implicit arguments (``structures''); simultaneous
  6035 type-inference over imports and text; see also HOL/ex/Locales.thy for
  6036 some examples;
  6037 
  6038 * Pure: the following commands have been ``localized'', supporting a
  6039 target locale specification "(in name)": 'lemma', 'theorem',
  6040 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  6041 stored both within the locale and at the theory level (exported and
  6042 qualified by the locale name);
  6043 
  6044 * Pure: theory goals may now be specified in ``long'' form, with
  6045 ad-hoc contexts consisting of arbitrary locale elements. for example
  6046 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  6047 definitions may be given, too); the result is a meta-level rule with
  6048 the context elements being discharged in the obvious way;
  6049 
  6050 * Pure: new proof command 'using' allows to augment currently used
  6051 facts after a goal statement ('using' is syntactically analogous to
  6052 'apply', but acts on the goal's facts only); this allows chained facts
  6053 to be separated into parts given before and after a claim, as in
  6054 ``from a and b have C using d and e <proof>'';
  6055 
  6056 * Pure: renamed "antecedent" case to "rule_context";
  6057 
  6058 * Pure: new 'judgment' command records explicit information about the
  6059 object-logic embedding (used by several tools internally); no longer
  6060 use hard-wired "Trueprop";
  6061 
  6062 * Pure: added 'corollary' command;
  6063 
  6064 * Pure: fixed 'token_translation' command;
  6065 
  6066 * Pure: removed obsolete 'exported' attribute;
  6067 
  6068 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  6069 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  6070 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  6071 
  6072 * Pure: method 'atomize' presents local goal premises as object-level
  6073 statements (atomic meta-level propositions); setup controlled via
  6074 rewrite rules declarations of 'atomize' attribute; example
  6075 application: 'induct' method with proper rule statements in improper
  6076 proof *scripts*;
  6077 
  6078 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  6079 now consider the syntactic context of assumptions, giving a better
  6080 chance to get type-inference of the arguments right (this is
  6081 especially important for locales);
  6082 
  6083 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  6084 mode;
  6085 
  6086 * Pure/obtain: the formal conclusion "thesis", being marked as
  6087 ``internal'', may no longer be reference directly in the text;
  6088 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  6089 situations;
  6090 
  6091 * Pure: generic 'sym' attribute which declares a rule both as pure
  6092 'elim?' and for the 'symmetric' operation;
  6093 
  6094 * Pure: marginal comments ``--'' may now occur just anywhere in the
  6095 text; the fixed correlation with particular command syntax has been
  6096 discontinued;
  6097 
  6098 * Pure: new method 'rules' is particularly well-suited for proof
  6099 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  6100 but often produces more compact proof terms with less detours;
  6101 
  6102 * Pure/Provers/classical: simplified integration with pure rule
  6103 attributes and methods; the classical "intro?/elim?/dest?"
  6104 declarations coincide with the pure ones; the "rule" method no longer
  6105 includes classically swapped intros; "intro" and "elim" methods no
  6106 longer pick rules from the context; also got rid of ML declarations
  6107 AddXIs/AddXEs/AddXDs; all of this has some potential for
  6108 INCOMPATIBILITY;
  6109 
  6110 * Provers/classical: attribute 'swapped' produces classical inversions
  6111 of introduction rules;
  6112 
  6113 * Provers/simplifier: 'simplified' attribute may refer to explicit
  6114 rules instead of full simplifier context; 'iff' attribute handles
  6115 conditional rules;
  6116 
  6117 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  6118 
  6119 * HOL: 'recdef' now fails on unfinished automated proofs, use
  6120 "(permissive)" option to recover old behavior;
  6121 
  6122 * HOL: 'inductive' no longer features separate (collective) attributes
  6123 for 'intros' (was found too confusing);
  6124 
  6125 * HOL: properly declared induction rules less_induct and
  6126 wf_induct_rule;
  6127 
  6128 
  6129 *** HOL ***
  6130 
  6131 * HOL: moved over to sane numeral syntax; the new policy is as
  6132 follows:
  6133 
  6134   - 0 and 1 are polymorphic constants, which are defined on any
  6135   numeric type (nat, int, real etc.);
  6136 
  6137   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  6138   binary representation internally;
  6139 
  6140   - type nat has special constructor Suc, and generally prefers Suc 0
  6141   over 1::nat and Suc (Suc 0) over 2::nat;
  6142 
  6143 This change may cause significant problems of INCOMPATIBILITY; here
  6144 are some hints on converting existing sources:
  6145 
  6146   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  6147   entities, so expressions involving "-" (unary or binary minus) need
  6148   to be spaced properly;
  6149 
  6150   - existing occurrences of "1" may need to be constraint "1::nat" or
  6151   even replaced by Suc 0; similar for old "2";
  6152 
  6153   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  6154 
  6155   - remove all special provisions on numerals in proofs;
  6156 
  6157 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  6158 representation (depends on bin_arith_simps in the default context);
  6159 
  6160 * HOL: symbolic syntax for x^2 (numeral 2);
  6161 
  6162 * HOL: the class of all HOL types is now called "type" rather than
  6163 "term"; INCOMPATIBILITY, need to adapt references to this type class
  6164 in axclass/classes, instance/arities, and (usually rare) occurrences
  6165 in typings (of consts etc.); internally the class is called
  6166 "HOL.type", ML programs should refer to HOLogic.typeS;
  6167 
  6168 * HOL/record package improvements:
  6169   - new derived operations "fields" to build a partial record section,
  6170     "extend" to promote a fixed record to a record scheme, and
  6171     "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*
  6172     declared as simp by default;
  6173   - shared operations ("more", "fields", etc.) now need to be always
  6174     qualified) --- potential INCOMPATIBILITY;
  6175   - removed "make_scheme" operations (use "make" with "extend") --
  6176     INCOMPATIBILITY;
  6177   - removed "more" class (simply use "term") -- INCOMPATIBILITY;
  6178   - provides cases/induct rules for use with corresponding Isar
  6179     methods (for concrete records, record schemes, concrete more
  6180     parts, and schematic more parts -- in that order);
  6181   - internal definitions directly based on a light-weight abstract
  6182     theory of product types over typedef rather than datatype;
  6183 
  6184 * HOL: generic code generator for generating executable ML code from
  6185 specifications; specific support for HOL constructs such as inductive
  6186 datatypes and sets, as well as recursive functions; can be invoked
  6187 via 'generate_code' theory section;
  6188 
  6189 * HOL: canonical cases/induct rules for n-tuples (n = 3..7);
  6190 
  6191 * HOL: consolidated and renamed several theories.  In particular:
  6192         Ord.thy has been absorbed into HOL.thy
  6193         String.thy has been absorbed into List.thy
  6194 
  6195 * HOL: concrete setsum syntax "\<Sum>i:A. b" == "setsum (%i. b) A"
  6196 (beware of argument permutation!);
  6197 
  6198 * HOL: linorder_less_split superseded by linorder_cases;
  6199 
  6200 * HOL/List: "nodups" renamed to "distinct";
  6201 
  6202 * HOL: added "The" definite description operator; move Hilbert's "Eps"
  6203 to peripheral theory "Hilbert_Choice"; some INCOMPATIBILITIES:
  6204   - Ex_def has changed, now need to use some_eq_ex
  6205 
  6206 * HOL: made split_all_tac safe; EXISTING PROOFS MAY FAIL OR LOOP, so
  6207 in this (rare) case use:
  6208 
  6209   delSWrapper "split_all_tac"
  6210   addSbefore ("unsafe_split_all_tac", unsafe_split_all_tac)
  6211 
  6212 * HOL: added safe wrapper "split_conv_tac" to claset; EXISTING PROOFS
  6213 MAY FAIL;
  6214 
  6215 * HOL: introduced f^n = f o ... o f; warning: due to the limits of
  6216 Isabelle's type classes, ^ on functions and relations has too general
  6217 a domain, namely ('a * 'b) set and 'a => 'b; this means that it may be
  6218 necessary to attach explicit type constraints;
  6219 
  6220 * HOL/Relation: the prefix name of the infix "O" has been changed from
  6221 "comp" to "rel_comp"; INCOMPATIBILITY: a few theorems have been
  6222 renamed accordingly (eg "compI" -> "rel_compI").
  6223 
  6224 * HOL: syntax translations now work properly with numerals and records
  6225 expressions;
  6226 
  6227 * HOL: bounded abstraction now uses syntax "%" / "\<lambda>" instead
  6228 of "lam" -- INCOMPATIBILITY;
  6229 
  6230 * HOL: got rid of some global declarations (potential INCOMPATIBILITY
  6231 for ML tools): const "()" renamed "Product_Type.Unity", type "unit"
  6232 renamed "Product_Type.unit";
  6233 
  6234 * HOL: renamed rtrancl_into_rtrancl2 to converse_rtrancl_into_rtrancl
  6235 
  6236 * HOL: removed obsolete theorem "optionE" (use "option.exhaust", or
  6237 the "cases" method);
  6238 
  6239 * HOL/GroupTheory: group theory examples including Sylow's theorem (by
  6240 Florian Kammller);
  6241 
  6242 * HOL/IMP: updated and converted to new-style theory format; several
  6243 parts turned into readable document, with proper Isar proof texts and
  6244 some explanations (by Gerwin Klein);
  6245 
  6246 * HOL-Real: added Complex_Numbers (by Gertrud Bauer);
  6247 
  6248 * HOL-Hyperreal is now a logic image;
  6249 
  6250 
  6251 *** HOLCF ***
  6252 
  6253 * Isar: consts/constdefs supports mixfix syntax for continuous
  6254 operations;
  6255 
  6256 * Isar: domain package adapted to new-style theory format, e.g. see
  6257 HOLCF/ex/Dnat.thy;
  6258 
  6259 * theory Lift: proper use of rep_datatype lift instead of ML hacks --
  6260 potential INCOMPATIBILITY; now use plain induct_tac instead of former
  6261 lift.induct_tac, always use UU instead of Undef;
  6262 
  6263 * HOLCF/IMP: updated and converted to new-style theory;
  6264 
  6265 
  6266 *** ZF ***
  6267 
  6268 * Isar: proper integration of logic-specific tools and packages,
  6269 including theory commands '(co)inductive', '(co)datatype',
  6270 'rep_datatype', 'inductive_cases', as well as methods 'ind_cases',
  6271 'induct_tac', 'case_tac', and 'typecheck' (with attribute 'TC');
  6272 
  6273 * theory Main no longer includes AC; for the Axiom of Choice, base
  6274 your theory on Main_ZFC;
  6275 
  6276 * the integer library now covers quotients and remainders, with many
  6277 laws relating division to addition, multiplication, etc.;
  6278 
  6279 * ZF/UNITY: Chandy and Misra's UNITY is now available in ZF, giving a
  6280 typeless version of the formalism;
  6281 
  6282 * ZF/AC, Coind, IMP, Resid: updated and converted to new-style theory
  6283 format;
  6284 
  6285 * ZF/Induct: new directory for examples of inductive definitions,
  6286 including theory Multiset for multiset orderings; converted to
  6287 new-style theory format;
  6288 
  6289 * ZF: many new theorems about lists, ordinals, etc.;
  6290 
  6291 
  6292 *** General ***
  6293 
  6294 * Pure/kernel: meta-level proof terms (by Stefan Berghofer); reference
  6295 variable proof controls level of detail: 0 = no proofs (only oracle
  6296 dependencies), 1 = lemma dependencies, 2 = compact proof terms; see
  6297 also ref manual for further ML interfaces;
  6298 
  6299 * Pure/axclass: removed obsolete ML interface
  6300 goal_subclass/goal_arity;
  6301 
  6302 * Pure/syntax: new token syntax "num" for plain numerals (without "#"
  6303 of "xnum"); potential INCOMPATIBILITY, since -0, -1 etc. are now
  6304 separate tokens, so expressions involving minus need to be spaced
  6305 properly;
  6306 
  6307 * Pure/syntax: support non-oriented infixes, using keyword "infix"
  6308 rather than "infixl" or "infixr";
  6309 
  6310 * Pure/syntax: concrete syntax for dummy type variables admits genuine
  6311 sort constraint specifications in type inference; e.g. "x::_::foo"
  6312 ensures that the type of "x" is of sort "foo" (but not necessarily a
  6313 type variable);
  6314 
  6315 * Pure/syntax: print modes "type_brackets" and "no_type_brackets"
  6316 control output of nested => (types); the default behavior is
  6317 "type_brackets";
  6318 
  6319 * Pure/syntax: builtin parse translation for "_constify" turns valued
  6320 tokens into AST constants;
  6321 
  6322 * Pure/syntax: prefer later declarations of translations and print
  6323 translation functions; potential INCOMPATIBILITY: need to reverse
  6324 multiple declarations for same syntax element constant;
  6325 
  6326 * Pure/show_hyps reset by default (in accordance to existing Isar
  6327 practice);
  6328 
  6329 * Provers/classical: renamed addaltern to addafter, addSaltern to
  6330 addSafter;
  6331 
  6332 * Provers/clasimp: ``iff'' declarations now handle conditional rules
  6333 as well;
  6334 
  6335 * system: tested support for MacOS X; should be able to get Isabelle +
  6336 Proof General to work in a plain Terminal after installing Poly/ML
  6337 (e.g. from the Isabelle distribution area) and GNU bash alone
  6338 (e.g. from http://www.apple.com); full X11, XEmacs and X-Symbol
  6339 support requires further installations, e.g. from
  6340 http://fink.sourceforge.net/);
  6341 
  6342 * system: support Poly/ML 4.1.1 (able to manage larger heaps);
  6343 
  6344 * system: reduced base memory usage by Poly/ML (approx. 20 MB instead
  6345 of 40 MB), cf. ML_OPTIONS;
  6346 
  6347 * system: Proof General keywords specification is now part of the
  6348 Isabelle distribution (see etc/isar-keywords.el);
  6349 
  6350 * system: support for persistent Proof General sessions (refrain from
  6351 outdating all loaded theories on startup); user may create writable
  6352 logic images like this: ``isabelle -q HOL Test'';
  6353 
  6354 * system: smart selection of Isabelle process versus Isabelle
  6355 interface, accommodates case-insensitive file systems (e.g. HFS+); may
  6356 run both "isabelle" and "Isabelle" even if file names are badly
  6357 damaged (executable inspects the case of the first letter of its own
  6358 name); added separate "isabelle-process" and "isabelle-interface";
  6359 
  6360 * system: refrain from any attempt at filtering input streams; no
  6361 longer support ``8bit'' encoding of old isabelle font, instead proper
  6362 iso-latin characters may now be used; the related isatools
  6363 "symbolinput" and "nonascii" have disappeared as well;
  6364 
  6365 * system: removed old "xterm" interface (the print modes "xterm" and
  6366 "xterm_color" are still available for direct use in a suitable
  6367 terminal);
  6368 
  6369 
  6370 
  6371 New in Isabelle99-2 (February 2001)
  6372 -----------------------------------
  6373 
  6374 *** Overview of INCOMPATIBILITIES ***
  6375 
  6376 * HOL: please note that theories in the Library and elsewhere often use the
  6377 new-style (Isar) format; to refer to their theorems in an ML script you must
  6378 bind them to ML identifers by e.g.      val thm_name = thm "thm_name";
  6379 
  6380 * HOL: inductive package no longer splits induction rule aggressively,
  6381 but only as far as specified by the introductions given; the old
  6382 format may be recovered via ML function complete_split_rule or attribute
  6383 'split_rule (complete)';
  6384 
  6385 * HOL: induct renamed to lfp_induct, lfp_Tarski to lfp_unfold,
  6386 gfp_Tarski to gfp_unfold;
  6387 
  6388 * HOL: contrapos, contrapos2 renamed to contrapos_nn, contrapos_pp;
  6389 
  6390 * HOL: infix "dvd" now has priority 50 rather than 70 (because it is a
  6391 relation); infix "^^" has been renamed "``"; infix "``" has been
  6392 renamed "`"; "univalent" has been renamed "single_valued";
  6393 
  6394 * HOL/Real: "rinv" and "hrinv" replaced by overloaded "inverse"
  6395 operation;
  6396 
  6397 * HOLCF: infix "`" has been renamed "$"; the symbol syntax is \<cdot>;
  6398 
  6399 * Isar: 'obtain' no longer declares "that" fact as simp/intro;
  6400 
  6401 * Isar/HOL: method 'induct' now handles non-atomic goals; as a
  6402 consequence, it is no longer monotonic wrt. the local goal context
  6403 (which is now passed through the inductive cases);
  6404 
  6405 * Document preparation: renamed standard symbols \<ll> to \<lless> and
  6406 \<gg> to \<ggreater>;
  6407 
  6408 
  6409 *** Document preparation ***
  6410 
  6411 * \isabellestyle{NAME} selects version of Isabelle output (currently
  6412 available: are "it" for near math-mode best-style output, "sl" for
  6413 slanted text style, and "tt" for plain type-writer; if no
  6414 \isabellestyle command is given, output is according to slanted
  6415 type-writer);
  6416 
  6417 * support sub/super scripts (for single symbols only), input syntax is
  6418 like this: "A\<^sup>*" or "A\<^sup>\<star>";
  6419 
  6420 * some more standard symbols; see Appendix A of the system manual for
  6421 the complete list of symbols defined in isabellesym.sty;
  6422 
  6423 * improved isabelle style files; more abstract symbol implementation
  6424 (should now use \isamath{...} and \isatext{...} in custom symbol
  6425 definitions);
  6426 
  6427 * antiquotation @{goals} and @{subgoals} for output of *dynamic* goals
  6428 state; Note that presentation of goal states does not conform to
  6429 actual human-readable proof documents.  Please do not include goal
  6430 states into document output unless you really know what you are doing!
  6431 
  6432 * proper indentation of antiquoted output with proportional LaTeX
  6433 fonts;
  6434 
  6435 * no_document ML operator temporarily disables LaTeX document
  6436 generation;
  6437 
  6438 * isatool unsymbolize tunes sources for plain ASCII communication;
  6439 
  6440 
  6441 *** Isar ***
  6442 
  6443 * Pure: Isar now suffers initial goal statements to contain unbound
  6444 schematic variables (this does not conform to actual readable proof
  6445 documents, due to unpredictable outcome and non-compositional proof
  6446 checking); users who know what they are doing may use schematic goals
  6447 for Prolog-style synthesis of proven results;
  6448 
  6449 * Pure: assumption method (an implicit finishing) now handles actual
  6450 rules as well;
  6451 
  6452 * Pure: improved 'obtain' --- moved to Pure, insert "that" into
  6453 initial goal, declare "that" only as Pure intro (only for single
  6454 steps); the "that" rule assumption may now be involved in implicit
  6455 finishing, thus ".." becomes a feasible for trivial obtains;
  6456 
  6457 * Pure: default proof step now includes 'intro_classes'; thus trivial
  6458 instance proofs may be performed by "..";
  6459 
  6460 * Pure: ?thesis / ?this / "..." now work for pure meta-level
  6461 statements as well;
  6462 
  6463 * Pure: more robust selection of calculational rules;
  6464 
  6465 * Pure: the builtin notion of 'finished' goal now includes the ==-refl
  6466 rule (as well as the assumption rule);
  6467 
  6468 * Pure: 'thm_deps' command visualizes dependencies of theorems and
  6469 lemmas, using the graph browser tool;
  6470 
  6471 * Pure: predict failure of "show" in interactive mode;
  6472 
  6473 * Pure: 'thms_containing' now takes actual terms as arguments;
  6474 
  6475 * HOL: improved method 'induct' --- now handles non-atomic goals
  6476 (potential INCOMPATIBILITY); tuned error handling;
  6477 
  6478 * HOL: cases and induct rules now provide explicit hints about the
  6479 number of facts to be consumed (0 for "type" and 1 for "set" rules);
  6480 any remaining facts are inserted into the goal verbatim;
  6481 
  6482 * HOL: local contexts (aka cases) may now contain term bindings as
  6483 well; the 'cases' and 'induct' methods new provide a ?case binding for
  6484 the result to be shown in each case;
  6485 
  6486 * HOL: added 'recdef_tc' command;
  6487 
  6488 * isatool convert assists in eliminating legacy ML scripts;
  6489 
  6490 
  6491 *** HOL ***
  6492 
  6493 * HOL/Library: a collection of generic theories to be used together
  6494 with main HOL; the theory loader path already includes this directory
  6495 by default; the following existing theories have been moved here:
  6496 HOL/Induct/Multiset, HOL/Induct/Acc (as Accessible_Part), HOL/While
  6497 (as While_Combinator), HOL/Lex/Prefix (as List_Prefix);
  6498 
  6499 * HOL/Unix: "Some aspects of Unix file-system security", a typical
  6500 modelling and verification task performed in Isabelle/HOL +
  6501 Isabelle/Isar + Isabelle document preparation (by Markus Wenzel).
  6502 
  6503 * HOL/Algebra: special summation operator SUM no longer exists, it has
  6504 been replaced by setsum; infix 'assoc' now has priority 50 (like
  6505 'dvd'); axiom 'one_not_zero' has been moved from axclass 'ring' to
  6506 'domain', this makes the theory consistent with mathematical
  6507 literature;
  6508 
  6509 * HOL basics: added overloaded operations "inverse" and "divide"
  6510 (infix "/"), syntax for generic "abs" operation, generic summation
  6511 operator \<Sum>;
  6512 
  6513 * HOL/typedef: simplified package, provide more useful rules (see also
  6514 HOL/subset.thy);
  6515 
  6516 * HOL/datatype: induction rule for arbitrarily branching datatypes is
  6517 now expressed as a proper nested rule (old-style tactic scripts may
  6518 require atomize_strip_tac to cope with non-atomic premises);
  6519 
  6520 * HOL: renamed theory "Prod" to "Product_Type", renamed "split" rule
  6521 to "split_conv" (old name still available for compatibility);
  6522 
  6523 * HOL: improved concrete syntax for strings (e.g. allows translation
  6524 rules with string literals);
  6525 
  6526 * HOL-Real-Hyperreal: this extends HOL-Real with the hyperreals
  6527  and Fleuriot's mechanization of analysis, including the transcendental
  6528  functions for the reals;
  6529 
  6530 * HOL/Real, HOL/Hyperreal: improved arithmetic simplification;
  6531 
  6532 
  6533 *** CTT ***
  6534 
  6535 * CTT: x-symbol support for Pi, Sigma, -->, : (membership); note that
  6536 "lam" is displayed as TWO lambda-symbols
  6537 
  6538 * CTT: theory Main now available, containing everything (that is, Bool
  6539 and Arith);
  6540 
  6541 
  6542 *** General ***
  6543 
  6544 * Pure: the Simplifier has been implemented properly as a derived rule
  6545 outside of the actual kernel (at last!); the overall performance
  6546 penalty in practical applications is about 50%, while reliability of
  6547 the Isabelle inference kernel has been greatly improved;
  6548 
  6549 * print modes "brackets" and "no_brackets" control output of nested =>
  6550 (types) and ==> (props); the default behaviour is "brackets";
  6551 
  6552 * Provers: fast_tac (and friends) now handle actual object-logic rules
  6553 as assumptions as well;
  6554 
  6555 * system: support Poly/ML 4.0;
  6556 
  6557 * system: isatool install handles KDE version 1 or 2;
  6558 
  6559 
  6560 
  6561 New in Isabelle99-1 (October 2000)
  6562 ----------------------------------
  6563 
  6564 *** Overview of INCOMPATIBILITIES ***
  6565 
  6566 * HOL: simplification of natural numbers is much changed; to partly
  6567 recover the old behaviour (e.g. to prevent n+n rewriting to #2*n)
  6568 issue the following ML commands:
  6569 
  6570   Delsimprocs Nat_Numeral_Simprocs.cancel_numerals;
  6571   Delsimprocs [Nat_Numeral_Simprocs.combine_numerals];
  6572 
  6573 * HOL: simplification no longer dives into case-expressions; this is
  6574 controlled by "t.weak_case_cong" for each datatype t;
  6575 
  6576 * HOL: nat_less_induct renamed to less_induct;
  6577 
  6578 * HOL: systematic renaming of the SOME (Eps) rules, may use isatool
  6579 fixsome to patch .thy and .ML sources automatically;
  6580 
  6581   select_equality  -> some_equality
  6582   select_eq_Ex     -> some_eq_ex
  6583   selectI2EX       -> someI2_ex
  6584   selectI2         -> someI2
  6585   selectI          -> someI
  6586   select1_equality -> some1_equality
  6587   Eps_sym_eq       -> some_sym_eq_trivial
  6588   Eps_eq           -> some_eq_trivial
  6589 
  6590 * HOL: exhaust_tac on datatypes superceded by new generic case_tac;
  6591 
  6592 * HOL: removed obsolete theorem binding expand_if (refer to split_if
  6593 instead);
  6594 
  6595 * HOL: the recursion equations generated by 'recdef' are now called
  6596 f.simps instead of f.rules;
  6597 
  6598 * HOL: qed_spec_mp now also handles bounded ALL as well;
  6599 
  6600 * HOL: 0 is now overloaded, so the type constraint ":: nat" may
  6601 sometimes be needed;
  6602 
  6603 * HOL: the constant for "f``x" is now "image" rather than "op ``";
  6604 
  6605 * HOL: the constant for "f-``x" is now "vimage" rather than "op -``";
  6606 
  6607 * HOL: the disjoint sum is now "<+>" instead of "Plus"; the cartesian
  6608 product is now "<*>" instead of "Times"; the lexicographic product is
  6609 now "<*lex*>" instead of "**";
  6610 
  6611 * HOL: theory Sexp is now in HOL/Induct examples (it used to be part
  6612 of main HOL, but was unused); better use HOL's datatype package;
  6613 
  6614 * HOL: removed "symbols" syntax for constant "override" of theory Map;
  6615 the old syntax may be recovered as follows:
  6616 
  6617   syntax (symbols)
  6618     override  :: "('a ~=> 'b) => ('a ~=> 'b) => ('a ~=> 'b)"
  6619       (infixl "\\<oplus>" 100)
  6620 
  6621 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  6622 
  6623 * HOL/ML: even fewer consts are declared as global (see theories Ord,
  6624 Lfp, Gfp, WF); this only affects ML packages that refer to const names
  6625 internally;
  6626 
  6627 * HOL and ZF: syntax for quotienting wrt an equivalence relation
  6628 changed from A/r to A//r;
  6629 
  6630 * ZF: new treatment of arithmetic (nat & int) may break some old
  6631 proofs;
  6632 
  6633 * Isar: renamed some attributes (RS -> THEN, simplify -> simplified,
  6634 rulify -> rule_format, elimify -> elim_format, ...);
  6635 
  6636 * Isar/Provers: intro/elim/dest attributes changed; renamed
  6637 intro/intro!/intro!! flags to intro!/intro/intro? (in most cases, one
  6638 should have to change intro!! to intro? only); replaced "delrule" by
  6639 "rule del";
  6640 
  6641 * Isar/HOL: renamed "intrs" to "intros" in inductive definitions;
  6642 
  6643 * Provers: strengthened force_tac by using new first_best_tac;
  6644 
  6645 * LaTeX document preparation: several changes of isabelle.sty (see
  6646 lib/texinputs);
  6647 
  6648 
  6649 *** Document preparation ***
  6650 
  6651 * formal comments (text blocks etc.) in new-style theories may now
  6652 contain antiquotations of thm/prop/term/typ/text to be presented
  6653 according to latex print mode; concrete syntax is like this:
  6654 @{term[show_types] "f(x) = a + x"};
  6655 
  6656 * isatool mkdir provides easy setup of Isabelle session directories,
  6657 including proper document sources;
  6658 
  6659 * generated LaTeX sources are now deleted after successful run
  6660 (isatool document -c); may retain a copy somewhere else via -D option
  6661 of isatool usedir;
  6662 
  6663 * isatool usedir -D now lets isatool latex -o sty update the Isabelle
  6664 style files, achieving self-contained LaTeX sources and simplifying
  6665 LaTeX debugging;
  6666 
  6667 * old-style theories now produce (crude) LaTeX output as well;
  6668 
  6669 * browser info session directories are now self-contained (may be put
  6670 on WWW server seperately); improved graphs of nested sessions; removed
  6671 graph for 'all sessions';
  6672 
  6673 * several improvements in isabelle style files; \isabellestyle{it}
  6674 produces fake math mode output; \isamarkupheader is now \section by
  6675 default; see lib/texinputs/isabelle.sty etc.;
  6676 
  6677 
  6678 *** Isar ***
  6679 
  6680 * Isar/Pure: local results and corresponding term bindings are now
  6681 subject to Hindley-Milner polymorphism (similar to ML); this
  6682 accommodates incremental type-inference very nicely;
  6683 
  6684 * Isar/Pure: new derived language element 'obtain' supports
  6685 generalized existence reasoning;
  6686 
  6687 * Isar/Pure: new calculational elements 'moreover' and 'ultimately'
  6688 support accumulation of results, without applying any rules yet;
  6689 useful to collect intermediate results without explicit name
  6690 references, and for use with transitivity rules with more than 2
  6691 premises;
  6692 
  6693 * Isar/Pure: scalable support for case-analysis type proofs: new
  6694 'case' language element refers to local contexts symbolically, as
  6695 produced by certain proof methods; internally, case names are attached
  6696 to theorems as "tags";
  6697 
  6698 * Isar/Pure: theory command 'hide' removes declarations from
  6699 class/type/const name spaces;
  6700 
  6701 * Isar/Pure: theory command 'defs' supports option "(overloaded)" to
  6702 indicate potential overloading;
  6703 
  6704 * Isar/Pure: changed syntax of local blocks from {{ }} to { };
  6705 
  6706 * Isar/Pure: syntax of sorts made 'inner', i.e. have to write
  6707 "{a,b,c}" instead of {a,b,c};
  6708 
  6709 * Isar/Pure now provides its own version of intro/elim/dest
  6710 attributes; useful for building new logics, but beware of confusion
  6711 with the version in Provers/classical;
  6712 
  6713 * Isar/Pure: the local context of (non-atomic) goals is provided via
  6714 case name 'antecedent';
  6715 
  6716 * Isar/Pure: removed obsolete 'transfer' attribute (transfer of thms
  6717 to the current context is now done automatically);
  6718 
  6719 * Isar/Pure: theory command 'method_setup' provides a simple interface
  6720 for definining proof methods in ML;
  6721 
  6722 * Isar/Provers: intro/elim/dest attributes changed; renamed
  6723 intro/intro!/intro!! flags to intro!/intro/intro? (INCOMPATIBILITY, in
  6724 most cases, one should have to change intro!! to intro? only);
  6725 replaced "delrule" by "rule del";
  6726 
  6727 * Isar/Provers: new 'hypsubst' method, plain 'subst' method and
  6728 'symmetric' attribute (the latter supercedes [RS sym]);
  6729 
  6730 * Isar/Provers: splitter support (via 'split' attribute and 'simp'
  6731 method modifier); 'simp' method: 'only:' modifier removes loopers as
  6732 well (including splits);
  6733 
  6734 * Isar/Provers: Simplifier and Classical methods now support all kind
  6735 of modifiers used in the past, including 'cong', 'iff', etc.
  6736 
  6737 * Isar/Provers: added 'fastsimp' and 'clarsimp' methods (combination
  6738 of Simplifier and Classical reasoner);
  6739 
  6740 * Isar/HOL: new proof method 'cases' and improved version of 'induct'
  6741 now support named cases; major packages (inductive, datatype, primrec,
  6742 recdef) support case names and properly name parameters;
  6743 
  6744 * Isar/HOL: new transitivity rules for substitution in inequalities --
  6745 monotonicity conditions are extracted to be proven at end of
  6746 calculations;
  6747 
  6748 * Isar/HOL: removed 'case_split' thm binding, should use 'cases' proof
  6749 method anyway;
  6750 
  6751 * Isar/HOL: removed old expand_if = split_if; theorems if_splits =
  6752 split_if split_if_asm; datatype package provides theorems foo.splits =
  6753 foo.split foo.split_asm for each datatype;
  6754 
  6755 * Isar/HOL: tuned inductive package, rename "intrs" to "intros"
  6756 (potential INCOMPATIBILITY), emulation of mk_cases feature for proof
  6757 scripts: new 'inductive_cases' command and 'ind_cases' method; (Note:
  6758 use "(cases (simplified))" method in proper proof texts);
  6759 
  6760 * Isar/HOL: added global 'arith_split' attribute for 'arith' method;
  6761 
  6762 * Isar: names of theorems etc. may be natural numbers as well;
  6763 
  6764 * Isar: 'pr' command: optional arguments for goals_limit and
  6765 ProofContext.prems_limit; no longer prints theory contexts, but only
  6766 proof states;
  6767 
  6768 * Isar: diagnostic commands 'pr', 'thm', 'prop', 'term', 'typ' admit
  6769 additional print modes to be specified; e.g. "pr(latex)" will print
  6770 proof state according to the Isabelle LaTeX style;
  6771 
  6772 * Isar: improved support for emulating tactic scripts, including proof
  6773 methods 'rule_tac' etc., 'cut_tac', 'thin_tac', 'subgoal_tac',
  6774 'rename_tac', 'rotate_tac', 'tactic', and 'case_tac' / 'induct_tac'
  6775 (for HOL datatypes);
  6776 
  6777 * Isar: simplified (more robust) goal selection of proof methods: 1st
  6778 goal, all goals, or explicit goal specifier (tactic emulation); thus
  6779 'proof method scripts' have to be in depth-first order;
  6780 
  6781 * Isar: tuned 'let' syntax: replaced 'as' keyword by 'and';
  6782 
  6783 * Isar: removed 'help' command, which hasn't been too helpful anyway;
  6784 should instead use individual commands for printing items
  6785 (print_commands, print_methods etc.);
  6786 
  6787 * Isar: added 'nothing' --- the empty list of theorems;
  6788 
  6789 
  6790 *** HOL ***
  6791 
  6792 * HOL/MicroJava: formalization of a fragment of Java, together with a
  6793 corresponding virtual machine and a specification of its bytecode
  6794 verifier and a lightweight bytecode verifier, including proofs of
  6795 type-safety; by Gerwin Klein, Tobias Nipkow, David von Oheimb, and
  6796 Cornelia Pusch (see also the homepage of project Bali at
  6797 http://isabelle.in.tum.de/Bali/);
  6798 
  6799 * HOL/Algebra: new theory of rings and univariate polynomials, by
  6800 Clemens Ballarin;
  6801 
  6802 * HOL/NumberTheory: fundamental Theorem of Arithmetic, Chinese
  6803 Remainder Theorem, Fermat/Euler Theorem, Wilson's Theorem, by Thomas M
  6804 Rasmussen;
  6805 
  6806 * HOL/Lattice: fundamental concepts of lattice theory and order
  6807 structures, including duals, properties of bounds versus algebraic
  6808 laws, lattice operations versus set-theoretic ones, the Knaster-Tarski
  6809 Theorem for complete lattices etc.; may also serve as a demonstration
  6810 for abstract algebraic reasoning using axiomatic type classes, and
  6811 mathematics-style proof in Isabelle/Isar; by Markus Wenzel;
  6812 
  6813 * HOL/Prolog: a (bare-bones) implementation of Lambda-Prolog, by David
  6814 von Oheimb;
  6815 
  6816 * HOL/IMPP: extension of IMP with local variables and mutually
  6817 recursive procedures, by David von Oheimb;
  6818 
  6819 * HOL/Lambda: converted into new-style theory and document;
  6820 
  6821 * HOL/ex/Multiquote: example of multiple nested quotations and
  6822 anti-quotations -- basically a generalized version of de-Bruijn
  6823 representation; very useful in avoiding lifting of operations;
  6824 
  6825 * HOL/record: added general record equality rule to simpset; fixed
  6826 select-update simplification procedure to handle extended records as
  6827 well; admit "r" as field name;
  6828 
  6829 * HOL: 0 is now overloaded over the new sort "zero", allowing its use with
  6830 other numeric types and also as the identity of groups, rings, etc.;
  6831 
  6832 * HOL: new axclass plus_ac0 for addition with the AC-laws and 0 as identity.
  6833 Types nat and int belong to this axclass;
  6834 
  6835 * HOL: greatly improved simplification involving numerals of type nat, int, real:
  6836    (i + #8 + j) = Suc k simplifies to  #7 + (i + j) = k
  6837    i*j + k + j*#3*i     simplifies to  #4*(i*j) + k
  6838   two terms #m*u and #n*u are replaced by #(m+n)*u
  6839     (where #m, #n and u can implicitly be 1; this is simproc combine_numerals)
  6840   and the term/formula #m*u+x ~~ #n*u+y simplifies simplifies to #(m-n)+x ~~ y
  6841     or x ~~ #(n-m)+y, where ~~ is one of = < <= or - (simproc cancel_numerals);
  6842 
  6843 * HOL: meson_tac is available (previously in ex/meson.ML); it is a
  6844 powerful prover for predicate logic but knows nothing of clasets; see
  6845 ex/mesontest.ML and ex/mesontest2.ML for example applications;
  6846 
  6847 * HOL: new version of "case_tac" subsumes both boolean case split and
  6848 "exhaust_tac" on datatypes; INCOMPATIBILITY: exhaust_tac no longer
  6849 exists, may define val exhaust_tac = case_tac for ad-hoc portability;
  6850 
  6851 * HOL: simplification no longer dives into case-expressions: only the
  6852 selector expression is simplified, but not the remaining arms; to
  6853 enable full simplification of case-expressions for datatype t, you may
  6854 remove t.weak_case_cong from the simpset, either globally (Delcongs
  6855 [thm"t.weak_case_cong"];) or locally (delcongs [...]).
  6856 
  6857 * HOL/recdef: the recursion equations generated by 'recdef' for
  6858 function 'f' are now called f.simps instead of f.rules; if all
  6859 termination conditions are proved automatically, these simplification
  6860 rules are added to the simpset, as in primrec; rules may be named
  6861 individually as well, resulting in a separate list of theorems for
  6862 each equation;
  6863 
  6864 * HOL/While is a new theory that provides a while-combinator. It
  6865 permits the definition of tail-recursive functions without the
  6866 provision of a termination measure. The latter is necessary once the
  6867 invariant proof rule for while is applied.
  6868 
  6869 * HOL: new (overloaded) notation for the set of elements below/above
  6870 some element: {..u}, {..u(}, {l..}, {)l..}. See theory SetInterval.
  6871 
  6872 * HOL: theorems impI, allI, ballI bound as "strip";
  6873 
  6874 * HOL: new tactic induct_thm_tac: thm -> string -> int -> tactic
  6875 induct_tac th "x1 ... xn" expects th to have a conclusion of the form
  6876 P v1 ... vn and abbreviates res_inst_tac [("v1","x1"),...,("vn","xn")] th;
  6877 
  6878 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  6879 
  6880 * HOL: theory Sexp now in HOL/Induct examples (it used to be part of
  6881 main HOL, but was unused);
  6882 
  6883 * HOL: fewer consts declared as global (e.g. have to refer to
  6884 "Lfp.lfp" instead of "lfp" internally; affects ML packages only);
  6885 
  6886 * HOL: tuned AST representation of nested pairs, avoiding bogus output
  6887 in case of overlap with user translations (e.g. judgements over
  6888 tuples); (note that the underlying logical represenation is still
  6889 bogus);
  6890 
  6891 
  6892 *** ZF ***
  6893 
  6894 * ZF: simplification automatically cancels common terms in arithmetic
  6895 expressions over nat and int;
  6896 
  6897 * ZF: new treatment of nat to minimize type-checking: all operators
  6898 coerce their operands to a natural number using the function natify,
  6899 making the algebraic laws unconditional;
  6900 
  6901 * ZF: as above, for int: operators coerce their operands to an integer
  6902 using the function intify;
  6903 
  6904 * ZF: the integer library now contains many of the usual laws for the
  6905 orderings, including $<=, and monotonicity laws for $+ and $*;
  6906 
  6907 * ZF: new example ZF/ex/NatSum to demonstrate integer arithmetic
  6908 simplification;
  6909 
  6910 * FOL and ZF: AddIffs now available, giving theorems of the form P<->Q
  6911 to the simplifier and classical reasoner simultaneously;
  6912 
  6913 
  6914 *** General ***
  6915 
  6916 * Provers: blast_tac now handles actual object-logic rules as
  6917 assumptions; note that auto_tac uses blast_tac internally as well;
  6918 
  6919 * Provers: new functions rulify/rulify_no_asm: thm -> thm for turning
  6920 outer -->/All/Ball into ==>/!!; qed_spec_mp now uses rulify_no_asm;
  6921 
  6922 * Provers: delrules now handles destruct rules as well (no longer need
  6923 explicit make_elim);
  6924 
  6925 * Provers: Blast_tac now warns of and ignores "weak elimination rules" e.g.
  6926   [| inj ?f;          ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
  6927 use instead the strong form,
  6928   [| inj ?f; ~ ?W ==> ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
  6929 in HOL, FOL and ZF the function cla_make_elim will create such rules
  6930 from destruct-rules;
  6931 
  6932 * Provers: Simplifier.easy_setup provides a fast path to basic
  6933 Simplifier setup for new object-logics;
  6934 
  6935 * Pure: AST translation rules no longer require constant head on LHS;
  6936 
  6937 * Pure: improved name spaces: ambiguous output is qualified; support
  6938 for hiding of names;
  6939 
  6940 * system: smart setup of canonical ML_HOME, ISABELLE_INTERFACE, and
  6941 XSYMBOL_HOME; no longer need to do manual configuration in most
  6942 situations;
  6943 
  6944 * system: compression of ML heaps images may now be controlled via -c
  6945 option of isabelle and isatool usedir (currently only observed by
  6946 Poly/ML);
  6947 
  6948 * system: isatool installfonts may handle X-Symbol fonts as well (very
  6949 useful for remote X11);
  6950 
  6951 * system: provide TAGS file for Isabelle sources;
  6952 
  6953 * ML: infix 'OF' is a version of 'MRS' with more appropriate argument
  6954 order;
  6955 
  6956 * ML: renamed flags Syntax.trace_norm_ast to Syntax.trace_ast; global
  6957 timing flag supersedes proof_timing and Toplevel.trace;
  6958 
  6959 * ML: new combinators |>> and |>>> for incremental transformations
  6960 with secondary results (e.g. certain theory extensions):
  6961 
  6962 * ML: PureThy.add_defs gets additional argument to indicate potential
  6963 overloading (usually false);
  6964 
  6965 * ML: PureThy.add_thms/add_axioms/add_defs now return theorems as
  6966 results;
  6967 
  6968 
  6969 
  6970 New in Isabelle99 (October 1999)
  6971 --------------------------------
  6972 
  6973 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  6974 
  6975 * HOL: The THEN and ELSE parts of conditional expressions (if P then x else y)
  6976 are no longer simplified.  (This allows the simplifier to unfold recursive
  6977 functional programs.)  To restore the old behaviour, declare
  6978 
  6979     Delcongs [if_weak_cong];
  6980 
  6981 * HOL: Removed the obsolete syntax "Compl A"; use -A for set
  6982 complement;
  6983 
  6984 * HOL: the predicate "inj" is now defined by translation to "inj_on";
  6985 
  6986 * HOL/datatype: mutual_induct_tac no longer exists --
  6987   use induct_tac "x_1 ... x_n" instead of mutual_induct_tac ["x_1", ..., "x_n"]
  6988 
  6989 * HOL/typedef: fixed type inference for representing set; type
  6990 arguments now have to occur explicitly on the rhs as type constraints;
  6991 
  6992 * ZF: The con_defs part of an inductive definition may no longer refer
  6993 to constants declared in the same theory;
  6994 
  6995 * HOL, ZF: the function mk_cases, generated by the inductive
  6996 definition package, has lost an argument.  To simplify its result, it
  6997 uses the default simpset instead of a supplied list of theorems.
  6998 
  6999 * HOL/List: the constructors of type list are now Nil and Cons;
  7000 
  7001 * Simplifier: the type of the infix ML functions
  7002         setSSolver addSSolver setSolver addSolver
  7003 is now  simpset * solver -> simpset  where `solver' is a new abstract type
  7004 for packaging solvers. A solver is created via
  7005         mk_solver: string -> (thm list -> int -> tactic) -> solver
  7006 where the string argument is only a comment.
  7007 
  7008 
  7009 *** Proof tools ***
  7010 
  7011 * Provers/Arith/fast_lin_arith.ML contains a functor for creating a
  7012 decision procedure for linear arithmetic. Currently it is used for
  7013 types `nat', `int', and `real' in HOL (see below); it can, should and
  7014 will be instantiated for other types and logics as well.
  7015 
  7016 * The simplifier now accepts rewrite rules with flexible heads, eg
  7017      hom ?f ==> ?f(?x+?y) = ?f ?x + ?f ?y
  7018   They are applied like any rule with a non-pattern lhs, i.e. by first-order
  7019   matching.
  7020 
  7021 
  7022 *** General ***
  7023 
  7024 * New Isabelle/Isar subsystem provides an alternative to traditional
  7025 tactical theorem proving; together with the ProofGeneral/isar user
  7026 interface it offers an interactive environment for developing human
  7027 readable proof documents (Isar == Intelligible semi-automated
  7028 reasoning); for further information see isatool doc isar-ref,
  7029 src/HOL/Isar_examples and http://isabelle.in.tum.de/Isar/
  7030 
  7031 * improved and simplified presentation of theories: better HTML markup
  7032 (including colors), graph views in several sizes; isatool usedir now
  7033 provides a proper interface for user theories (via -P option); actual
  7034 document preparation based on (PDF)LaTeX is available as well (for
  7035 new-style theories only); see isatool doc system for more information;
  7036 
  7037 * native support for Proof General, both for classic Isabelle and
  7038 Isabelle/Isar;
  7039 
  7040 * ML function thm_deps visualizes dependencies of theorems and lemmas,
  7041 using the graph browser tool;
  7042 
  7043 * Isabelle manuals now also available as PDF;
  7044 
  7045 * theory loader rewritten from scratch (may not be fully
  7046 bug-compatible); old loadpath variable has been replaced by show_path,
  7047 add_path, del_path, reset_path functions; new operations such as
  7048 update_thy, touch_thy, remove_thy, use/update_thy_only (see also
  7049 isatool doc ref);
  7050 
  7051 * improved isatool install: option -k creates KDE application icon,
  7052 option -p DIR installs standalone binaries;
  7053 
  7054 * added ML_PLATFORM setting (useful for cross-platform installations);
  7055 more robust handling of platform specific ML images for SML/NJ;
  7056 
  7057 * the settings environment is now statically scoped, i.e. it is never
  7058 created again in sub-processes invoked from isabelle, isatool, or
  7059 Isabelle;
  7060 
  7061 * path element specification '~~' refers to '$ISABELLE_HOME';
  7062 
  7063 * in locales, the "assumes" and "defines" parts may be omitted if
  7064 empty;
  7065 
  7066 * new print_mode "xsymbols" for extended symbol support (e.g. genuine
  7067 long arrows);
  7068 
  7069 * new print_mode "HTML";
  7070 
  7071 * new flag show_tags controls display of tags of theorems (which are
  7072 basically just comments that may be attached by some tools);
  7073 
  7074 * Isamode 2.6 requires patch to accomodate change of Isabelle font
  7075 mode and goal output format:
  7076 
  7077 diff -r Isamode-2.6/elisp/isa-load.el Isamode/elisp/isa-load.el
  7078 244c244
  7079 <       (list (isa-getenv "ISABELLE") "-msymbols" logic-name)
  7080 ---
  7081 >       (list (isa-getenv "ISABELLE") "-misabelle_font" "-msymbols" logic-name)
  7082 diff -r Isabelle-2.6/elisp/isa-proofstate.el Isamode/elisp/isa-proofstate.el
  7083 181c181
  7084 < (defconst proofstate-proofstart-regexp "^Level [0-9]+$"
  7085 ---
  7086 > (defconst proofstate-proofstart-regexp "^Level [0-9]+"
  7087 
  7088 * function bind_thms stores lists of theorems (cf. bind_thm);
  7089 
  7090 * new shorthand tactics ftac, eatac, datac, fatac;
  7091 
  7092 * qed (and friends) now accept "" as result name; in that case the
  7093 theorem is not stored, but proper checks and presentation of the
  7094 result still apply;
  7095 
  7096 * theorem database now also indexes constants "Trueprop", "all",
  7097 "==>", "=="; thus thms_containing, findI etc. may retrieve more rules;
  7098 
  7099 
  7100 *** HOL ***
  7101 
  7102 ** HOL arithmetic **
  7103 
  7104 * There are now decision procedures for linear arithmetic over nat and
  7105 int:
  7106 
  7107 1. arith_tac copes with arbitrary formulae involving `=', `<', `<=',
  7108 `+', `-', `Suc', `min', `max' and numerical constants; other subterms
  7109 are treated as atomic; subformulae not involving type `nat' or `int'
  7110 are ignored; quantified subformulae are ignored unless they are
  7111 positive universal or negative existential. The tactic has to be
  7112 invoked by hand and can be a little bit slow. In particular, the
  7113 running time is exponential in the number of occurrences of `min' and
  7114 `max', and `-' on `nat'.
  7115 
  7116 2. fast_arith_tac is a cut-down version of arith_tac: it only takes
  7117 (negated) (in)equalities among the premises and the conclusion into
  7118 account (i.e. no compound formulae) and does not know about `min' and
  7119 `max', and `-' on `nat'. It is fast and is used automatically by the
  7120 simplifier.
  7121 
  7122 NB: At the moment, these decision procedures do not cope with mixed
  7123 nat/int formulae where the two parts interact, such as `m < n ==>
  7124 int(m) < int(n)'.
  7125 
  7126 * HOL/Numeral provides a generic theory of numerals (encoded
  7127 efficiently as bit strings); setup for types nat/int/real is in place;
  7128 INCOMPATIBILITY: since numeral syntax is now polymorphic, rather than
  7129 int, existing theories and proof scripts may require a few additional
  7130 type constraints;
  7131 
  7132 * integer division and remainder can now be performed on constant
  7133 arguments;
  7134 
  7135 * many properties of integer multiplication, division and remainder
  7136 are now available;
  7137 
  7138 * An interface to the Stanford Validity Checker (SVC) is available through the
  7139 tactic svc_tac.  Propositional tautologies and theorems of linear arithmetic
  7140 are proved automatically.  SVC must be installed separately, and its results
  7141 must be TAKEN ON TRUST (Isabelle does not check the proofs, but tags any
  7142 invocation of the underlying oracle).  For SVC see
  7143   http://verify.stanford.edu/SVC
  7144 
  7145 * IsaMakefile: the HOL-Real target now builds an actual image;
  7146 
  7147 
  7148 ** HOL misc **
  7149 
  7150 * HOL/Real/HahnBanach: the Hahn-Banach theorem for real vector spaces
  7151 (in Isabelle/Isar) -- by Gertrud Bauer;
  7152 
  7153 * HOL/BCV: generic model of bytecode verification, i.e. data-flow
  7154 analysis for assembly languages with subtypes;
  7155 
  7156 * HOL/TLA (Lamport's Temporal Logic of Actions): major reorganization
  7157 -- avoids syntactic ambiguities and treats state, transition, and
  7158 temporal levels more uniformly; introduces INCOMPATIBILITIES due to
  7159 changed syntax and (many) tactics;
  7160 
  7161 * HOL/inductive: Now also handles more general introduction rules such
  7162   as "ALL y. (y, x) : r --> y : acc r ==> x : acc r"; monotonicity
  7163   theorems are now maintained within the theory (maintained via the
  7164   "mono" attribute);
  7165 
  7166 * HOL/datatype: Now also handles arbitrarily branching datatypes
  7167   (using function types) such as
  7168 
  7169   datatype 'a tree = Atom 'a | Branch "nat => 'a tree"
  7170 
  7171 * HOL/record: record_simproc (part of the default simpset) takes care
  7172 of selectors applied to updated records; record_split_tac is no longer
  7173 part of the default claset; update_defs may now be removed from the
  7174 simpset in many cases; COMPATIBILITY: old behavior achieved by
  7175 
  7176   claset_ref () := claset() addSWrapper record_split_wrapper;
  7177   Delsimprocs [record_simproc]
  7178 
  7179 * HOL/typedef: fixed type inference for representing set; type
  7180 arguments now have to occur explicitly on the rhs as type constraints;
  7181 
  7182 * HOL/recdef (TFL): 'congs' syntax now expects comma separated list of theorem
  7183 names rather than an ML expression;
  7184 
  7185 * HOL/defer_recdef (TFL): like recdef but the well-founded relation can be
  7186 supplied later.  Program schemes can be defined, such as
  7187     "While B C s = (if B s then While B C (C s) else s)"
  7188 where the well-founded relation can be chosen after B and C have been given.
  7189 
  7190 * HOL/List: the constructors of type list are now Nil and Cons;
  7191 INCOMPATIBILITY: while [] and infix # syntax is still there, of
  7192 course, ML tools referring to List.list.op # etc. have to be adapted;
  7193 
  7194 * HOL_quantifiers flag superseded by "HOL" print mode, which is
  7195 disabled by default; run isabelle with option -m HOL to get back to
  7196 the original Gordon/HOL-style output;
  7197 
  7198 * HOL/Ord.thy: new bounded quantifier syntax (input only): ALL x<y. P,
  7199 ALL x<=y. P, EX x<y. P, EX x<=y. P;
  7200 
  7201 * HOL basic syntax simplified (more orthogonal): all variants of
  7202 All/Ex now support plain / symbolic / HOL notation; plain syntax for
  7203 Eps operator is provided as well: "SOME x. P[x]";
  7204 
  7205 * HOL/Sum.thy: sum_case has been moved to HOL/Datatype;
  7206 
  7207 * HOL/Univ.thy: infix syntax <*>, <+>, <**>, <+> eliminated and made
  7208 thus available for user theories;
  7209 
  7210 * HOLCF/IOA/Sequents: renamed 'Cons' to 'Consq' to avoid clash with
  7211 HOL/List; hardly an INCOMPATIBILITY since '>>' syntax is used all the
  7212 time;
  7213 
  7214 * HOL: new tactic smp_tac: int -> int -> tactic, which applies spec
  7215 several times and then mp;
  7216 
  7217 
  7218 *** LK ***
  7219 
  7220 * the notation <<...>> is now available as a notation for sequences of
  7221 formulas;
  7222 
  7223 * the simplifier is now installed
  7224 
  7225 * the axiom system has been generalized (thanks to Soren Heilmann)
  7226 
  7227 * the classical reasoner now has a default rule database
  7228 
  7229 
  7230 *** ZF ***
  7231 
  7232 * new primrec section allows primitive recursive functions to be given
  7233 directly (as in HOL) over datatypes and the natural numbers;
  7234 
  7235 * new tactics induct_tac and exhaust_tac for induction (or case
  7236 analysis) over datatypes and the natural numbers;
  7237 
  7238 * the datatype declaration of type T now defines the recursor T_rec;
  7239 
  7240 * simplification automatically does freeness reasoning for datatype
  7241 constructors;
  7242 
  7243 * automatic type-inference, with AddTCs command to insert new
  7244 type-checking rules;
  7245 
  7246 * datatype introduction rules are now added as Safe Introduction rules
  7247 to the claset;
  7248 
  7249 * the syntax "if P then x else y" is now available in addition to
  7250 if(P,x,y);
  7251 
  7252 
  7253 *** Internal programming interfaces ***
  7254 
  7255 * tuned simplifier trace output; new flag debug_simp;
  7256 
  7257 * structures Vartab / Termtab (instances of TableFun) offer efficient
  7258 tables indexed by indexname_ord / term_ord (compatible with aconv);
  7259 
  7260 * AxClass.axclass_tac lost the theory argument;
  7261 
  7262 * tuned current_goals_markers semantics: begin / end goal avoids
  7263 printing empty lines;
  7264 
  7265 * removed prs and prs_fn hook, which was broken because it did not
  7266 include \n in its semantics, forcing writeln to add one
  7267 uncoditionally; replaced prs_fn by writeln_fn; consider std_output:
  7268 string -> unit if you really want to output text without newline;
  7269 
  7270 * Symbol.output subject to print mode; INCOMPATIBILITY: defaults to
  7271 plain output, interface builders may have to enable 'isabelle_font'
  7272 mode to get Isabelle font glyphs as before;
  7273 
  7274 * refined token_translation interface; INCOMPATIBILITY: output length
  7275 now of type real instead of int;
  7276 
  7277 * theory loader actions may be traced via new ThyInfo.add_hook
  7278 interface (see src/Pure/Thy/thy_info.ML); example application: keep
  7279 your own database of information attached to *whole* theories -- as
  7280 opposed to intra-theory data slots offered via TheoryDataFun;
  7281 
  7282 * proper handling of dangling sort hypotheses (at last!);
  7283 Thm.strip_shyps and Drule.strip_shyps_warning take care of removing
  7284 extra sort hypotheses that can be witnessed from the type signature;
  7285 the force_strip_shyps flag is gone, any remaining shyps are simply
  7286 left in the theorem (with a warning issued by strip_shyps_warning);
  7287 
  7288 
  7289 
  7290 New in Isabelle98-1 (October 1998)
  7291 ----------------------------------
  7292 
  7293 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  7294 
  7295 * several changes of automated proof tools;
  7296 
  7297 * HOL: major changes to the inductive and datatype packages, including
  7298 some minor incompatibilities of theory syntax;
  7299 
  7300 * HOL: renamed r^-1 to 'converse' from 'inverse'; 'inj_onto' is now
  7301 called `inj_on';
  7302 
  7303 * HOL: removed duplicate thms in Arith:
  7304   less_imp_add_less  should be replaced by  trans_less_add1
  7305   le_imp_add_le      should be replaced by  trans_le_add1
  7306 
  7307 * HOL: unary minus is now overloaded (new type constraints may be
  7308 required);
  7309 
  7310 * HOL and ZF: unary minus for integers is now #- instead of #~.  In
  7311 ZF, expressions such as n#-1 must be changed to n#- 1, since #-1 is
  7312 now taken as an integer constant.
  7313 
  7314 * Pure: ML function 'theory_of' renamed to 'theory';
  7315 
  7316 
  7317 *** Proof tools ***
  7318 
  7319 * Simplifier:
  7320   1. Asm_full_simp_tac is now more aggressive.
  7321      1. It will sometimes reorient premises if that increases their power to
  7322         simplify.
  7323      2. It does no longer proceed strictly from left to right but may also
  7324         rotate premises to achieve further simplification.
  7325      For compatibility reasons there is now Asm_lr_simp_tac which is like the
  7326      old Asm_full_simp_tac in that it does not rotate premises.
  7327   2. The simplifier now knows a little bit about nat-arithmetic.
  7328 
  7329 * Classical reasoner: wrapper mechanism for the classical reasoner now
  7330 allows for selected deletion of wrappers, by introduction of names for
  7331 wrapper functionals.  This implies that addbefore, addSbefore,
  7332 addaltern, and addSaltern now take a pair (name, tactic) as argument,
  7333 and that adding two tactics with the same name overwrites the first
  7334 one (emitting a warning).
  7335   type wrapper = (int -> tactic) -> (int -> tactic)
  7336   setWrapper, setSWrapper, compWrapper and compSWrapper are replaced by
  7337   addWrapper, addSWrapper: claset * (string * wrapper) -> claset
  7338   delWrapper, delSWrapper: claset *  string            -> claset
  7339   getWrapper is renamed to appWrappers, getSWrapper to appSWrappers;
  7340 
  7341 * Classical reasoner: addbefore/addSbefore now have APPEND/ORELSE
  7342 semantics; addbefore now affects only the unsafe part of step_tac
  7343 etc.; this affects addss/auto_tac/force_tac, so EXISTING PROOFS MAY
  7344 FAIL, but proofs should be fixable easily, e.g. by replacing Auto_tac
  7345 by Force_tac;
  7346 
  7347 * Classical reasoner: setwrapper to setWrapper and compwrapper to
  7348 compWrapper; added safe wrapper (and access functions for it);
  7349 
  7350 * HOL/split_all_tac is now much faster and fails if there is nothing
  7351 to split.  Some EXISTING PROOFS MAY REQUIRE ADAPTION because the order
  7352 and the names of the automatically generated variables have changed.
  7353 split_all_tac has moved within claset() from unsafe wrappers to safe
  7354 wrappers, which means that !!-bound variables are split much more
  7355 aggressively, and safe_tac and clarify_tac now split such variables.
  7356 If this splitting is not appropriate, use delSWrapper "split_all_tac".
  7357 Note: the same holds for record_split_tac, which does the job of
  7358 split_all_tac for record fields.
  7359 
  7360 * HOL/Simplifier: Rewrite rules for case distinctions can now be added
  7361 permanently to the default simpset using Addsplits just like
  7362 Addsimps. They can be removed via Delsplits just like
  7363 Delsimps. Lower-case versions are also available.
  7364 
  7365 * HOL/Simplifier: The rule split_if is now part of the default
  7366 simpset. This means that the simplifier will eliminate all occurrences
  7367 of if-then-else in the conclusion of a goal. To prevent this, you can
  7368 either remove split_if completely from the default simpset by
  7369 `Delsplits [split_if]' or remove it in a specific call of the
  7370 simplifier using `... delsplits [split_if]'.  You can also add/delete
  7371 other case splitting rules to/from the default simpset: every datatype
  7372 generates suitable rules `split_t_case' and `split_t_case_asm' (where
  7373 t is the name of the datatype).
  7374 
  7375 * Classical reasoner / Simplifier combination: new force_tac (and
  7376 derivatives Force_tac, force) combines rewriting and classical
  7377 reasoning (and whatever other tools) similarly to auto_tac, but is
  7378 aimed to solve the given subgoal completely.
  7379 
  7380 
  7381 *** General ***
  7382 
  7383 * new top-level commands `Goal' and `Goalw' that improve upon `goal'
  7384 and `goalw': the theory is no longer needed as an explicit argument -
  7385 the current theory context is used; assumptions are no longer returned
  7386 at the ML-level unless one of them starts with ==> or !!; it is
  7387 recommended to convert to these new commands using isatool fixgoal
  7388 (backup your sources first!);
  7389 
  7390 * new top-level commands 'thm' and 'thms' for retrieving theorems from
  7391 the current theory context, and 'theory' to lookup stored theories;
  7392 
  7393 * new theory section 'locale' for declaring constants, assumptions and
  7394 definitions that have local scope;
  7395 
  7396 * new theory section 'nonterminals' for purely syntactic types;
  7397 
  7398 * new theory section 'setup' for generic ML setup functions
  7399 (e.g. package initialization);
  7400 
  7401 * the distribution now includes Isabelle icons: see
  7402 lib/logo/isabelle-{small,tiny}.xpm;
  7403 
  7404 * isatool install - install binaries with absolute references to
  7405 ISABELLE_HOME/bin;
  7406 
  7407 * isatool logo -- create instances of the Isabelle logo (as EPS);
  7408 
  7409 * print mode 'emacs' reserved for Isamode;
  7410 
  7411 * support multiple print (ast) translations per constant name;
  7412 
  7413 * theorems involving oracles are now printed with a suffixed [!];
  7414 
  7415 
  7416 *** HOL ***
  7417 
  7418 * there is now a tutorial on Isabelle/HOL (do 'isatool doc tutorial');
  7419 
  7420 * HOL/inductive package reorganized and improved: now supports mutual
  7421 definitions such as
  7422 
  7423   inductive EVEN ODD
  7424     intrs
  7425       null "0 : EVEN"
  7426       oddI "n : EVEN ==> Suc n : ODD"
  7427       evenI "n : ODD ==> Suc n : EVEN"
  7428 
  7429 new theorem list "elims" contains an elimination rule for each of the
  7430 recursive sets; inductive definitions now handle disjunctive premises
  7431 correctly (also ZF);
  7432 
  7433 INCOMPATIBILITIES: requires Inductive as an ancestor; component
  7434 "mutual_induct" no longer exists - the induction rule is always
  7435 contained in "induct";
  7436 
  7437 
  7438 * HOL/datatype package re-implemented and greatly improved: now
  7439 supports mutually recursive datatypes such as
  7440 
  7441   datatype
  7442     'a aexp = IF_THEN_ELSE ('a bexp) ('a aexp) ('a aexp)
  7443             | SUM ('a aexp) ('a aexp)
  7444             | DIFF ('a aexp) ('a aexp)
  7445             | NUM 'a
  7446   and
  7447     'a bexp = LESS ('a aexp) ('a aexp)
  7448             | AND ('a bexp) ('a bexp)
  7449             | OR ('a bexp) ('a bexp)
  7450 
  7451 as well as indirectly recursive datatypes such as
  7452 
  7453   datatype
  7454     ('a, 'b) term = Var 'a
  7455                   | App 'b ((('a, 'b) term) list)
  7456 
  7457 The new tactic  mutual_induct_tac [<var_1>, ..., <var_n>] i  performs
  7458 induction on mutually / indirectly recursive datatypes.
  7459 
  7460 Primrec equations are now stored in theory and can be accessed via
  7461 <function_name>.simps.
  7462 
  7463 INCOMPATIBILITIES:
  7464 
  7465   - Theories using datatypes must now have theory Datatype as an
  7466     ancestor.
  7467   - The specific <typename>.induct_tac no longer exists - use the
  7468     generic induct_tac instead.
  7469   - natE has been renamed to nat.exhaust - use exhaust_tac
  7470     instead of res_inst_tac ... natE. Note that the variable
  7471     names in nat.exhaust differ from the names in natE, this
  7472     may cause some "fragile" proofs to fail.
  7473   - The theorems split_<typename>_case and split_<typename>_case_asm
  7474     have been renamed to <typename>.split and <typename>.split_asm.
  7475   - Since default sorts of type variables are now handled correctly,
  7476     some datatype definitions may have to be annotated with explicit
  7477     sort constraints.
  7478   - Primrec definitions no longer require function name and type
  7479     of recursive argument.
  7480 
  7481 Consider using isatool fixdatatype to adapt your theories and proof
  7482 scripts to the new package (backup your sources first!).
  7483 
  7484 
  7485 * HOL/record package: considerably improved implementation; now
  7486 includes concrete syntax for record types, terms, updates; theorems
  7487 for surjective pairing and splitting !!-bound record variables; proof
  7488 support is as follows:
  7489 
  7490   1) standard conversions (selectors or updates applied to record
  7491 constructor terms) are part of the standard simpset;
  7492 
  7493   2) inject equations of the form ((x, y) = (x', y')) == x=x' & y=y' are
  7494 made part of standard simpset and claset via addIffs;
  7495 
  7496   3) a tactic for record field splitting (record_split_tac) is part of
  7497 the standard claset (addSWrapper);
  7498 
  7499 To get a better idea about these rules you may retrieve them via
  7500 something like 'thms "foo.simps"' or 'thms "foo.iffs"', where "foo" is
  7501 the name of your record type.
  7502 
  7503 The split tactic 3) conceptually simplifies by the following rule:
  7504 
  7505   "(!!x. PROP ?P x) == (!!a b. PROP ?P (a, b))"
  7506 
  7507 Thus any record variable that is bound by meta-all will automatically
  7508 blow up into some record constructor term, consequently the
  7509 simplifications of 1), 2) apply.  Thus force_tac, auto_tac etc. shall
  7510 solve record problems automatically.
  7511 
  7512 
  7513 * reorganized the main HOL image: HOL/Integ and String loaded by
  7514 default; theory Main includes everything;
  7515 
  7516 * automatic simplification of integer sums and comparisons, using cancellation;
  7517 
  7518 * added option_map_eq_Some and not_Some_eq to the default simpset and claset;
  7519 
  7520 * added disj_not1 = "(~P | Q) = (P --> Q)" to the default simpset;
  7521 
  7522 * many new identities for unions, intersections, set difference, etc.;
  7523 
  7524 * expand_if, expand_split, expand_sum_case and expand_nat_case are now
  7525 called split_if, split_split, split_sum_case and split_nat_case (to go
  7526 with add/delsplits);
  7527 
  7528 * HOL/Prod introduces simplification procedure unit_eq_proc rewriting
  7529 (?x::unit) = (); this is made part of the default simpset, which COULD
  7530 MAKE EXISTING PROOFS FAIL under rare circumstances (consider
  7531 'Delsimprocs [unit_eq_proc];' as last resort); also note that
  7532 unit_abs_eta_conv is added in order to counter the effect of
  7533 unit_eq_proc on (%u::unit. f u), replacing it by f rather than by
  7534 %u.f();
  7535 
  7536 * HOL/Fun INCOMPATIBILITY: `inj_onto' is now called `inj_on' (which
  7537 makes more sense);
  7538 
  7539 * HOL/Set INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
  7540   It and 'sym RS equals0D' are now in the default  claset, giving automatic
  7541   disjointness reasoning but breaking a few old proofs.
  7542 
  7543 * HOL/Relation INCOMPATIBILITY: renamed the relational operator r^-1
  7544 to 'converse' from 'inverse' (for compatibility with ZF and some
  7545 literature);
  7546 
  7547 * HOL/recdef can now declare non-recursive functions, with {} supplied as
  7548 the well-founded relation;
  7549 
  7550 * HOL/Set INCOMPATIBILITY: the complement of set A is now written -A instead of
  7551     Compl A.  The "Compl" syntax remains available as input syntax for this
  7552     release ONLY.
  7553 
  7554 * HOL/Update: new theory of function updates:
  7555     f(a:=b) == %x. if x=a then b else f x
  7556 may also be iterated as in f(a:=b,c:=d,...);
  7557 
  7558 * HOL/Vimage: new theory for inverse image of a function, syntax f-``B;
  7559 
  7560 * HOL/List:
  7561   - new function list_update written xs[i:=v] that updates the i-th
  7562     list position. May also be iterated as in xs[i:=a,j:=b,...].
  7563   - new function `upt' written [i..j(] which generates the list
  7564     [i,i+1,...,j-1], i.e. the upper bound is excluded. To include the upper
  7565     bound write [i..j], which is a shorthand for [i..j+1(].
  7566   - new lexicographic orderings and corresponding wellfoundedness theorems.
  7567 
  7568 * HOL/Arith:
  7569   - removed 'pred' (predecessor) function;
  7570   - generalized some theorems about n-1;
  7571   - many new laws about "div" and "mod";
  7572   - new laws about greatest common divisors (see theory ex/Primes);
  7573 
  7574 * HOL/Relation: renamed the relational operator r^-1 "converse"
  7575 instead of "inverse";
  7576 
  7577 * HOL/Induct/Multiset: a theory of multisets, including the wellfoundedness
  7578   of the multiset ordering;
  7579 
  7580 * directory HOL/Real: a construction of the reals using Dedekind cuts
  7581   (not included by default);
  7582 
  7583 * directory HOL/UNITY: Chandy and Misra's UNITY formalism;
  7584 
  7585 * directory HOL/Hoare: a new version of Hoare logic which permits many-sorted
  7586   programs, i.e. different program variables may have different types.
  7587 
  7588 * calling (stac rew i) now fails if "rew" has no effect on the goal
  7589   [previously, this check worked only if the rewrite rule was unconditional]
  7590   Now rew can involve either definitions or equalities (either == or =).
  7591 
  7592 
  7593 *** ZF ***
  7594 
  7595 * theory Main includes everything; INCOMPATIBILITY: theory ZF.thy contains
  7596   only the theorems proved on ZF.ML;
  7597 
  7598 * ZF INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
  7599   It and 'sym RS equals0D' are now in the default  claset, giving automatic
  7600   disjointness reasoning but breaking a few old proofs.
  7601 
  7602 * ZF/Update: new theory of function updates
  7603     with default rewrite rule  f(x:=y) ` z = if(z=x, y, f`z)
  7604   may also be iterated as in f(a:=b,c:=d,...);
  7605 
  7606 * in  let x=t in u(x), neither t nor u(x) has to be an FOL term.
  7607 
  7608 * calling (stac rew i) now fails if "rew" has no effect on the goal
  7609   [previously, this check worked only if the rewrite rule was unconditional]
  7610   Now rew can involve either definitions or equalities (either == or =).
  7611 
  7612 * case_tac provided for compatibility with HOL
  7613     (like the old excluded_middle_tac, but with subgoals swapped)
  7614 
  7615 
  7616 *** Internal programming interfaces ***
  7617 
  7618 * Pure: several new basic modules made available for general use, see
  7619 also src/Pure/README;
  7620 
  7621 * improved the theory data mechanism to support encapsulation (data
  7622 kind name replaced by private Object.kind, acting as authorization
  7623 key); new type-safe user interface via functor TheoryDataFun; generic
  7624 print_data function becomes basically useless;
  7625 
  7626 * removed global_names compatibility flag -- all theory declarations
  7627 are qualified by default;
  7628 
  7629 * module Pure/Syntax now offers quote / antiquote translation
  7630 functions (useful for Hoare logic etc. with implicit dependencies);
  7631 see HOL/ex/Antiquote for an example use;
  7632 
  7633 * Simplifier now offers conversions (asm_)(full_)rewrite: simpset ->
  7634 cterm -> thm;
  7635 
  7636 * new tactical CHANGED_GOAL for checking that a tactic modifies a
  7637 subgoal;
  7638 
  7639 * Display.print_goals function moved to Locale.print_goals;
  7640 
  7641 * standard print function for goals supports current_goals_markers
  7642 variable for marking begin of proof, end of proof, start of goal; the
  7643 default is ("", "", ""); setting current_goals_markers := ("<proof>",
  7644 "</proof>", "<goal>") causes SGML like tagged proof state printing,
  7645 for example;
  7646 
  7647 
  7648 
  7649 New in Isabelle98 (January 1998)
  7650 --------------------------------
  7651 
  7652 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  7653 
  7654 * changed lexical syntax of terms / types: dots made part of long
  7655 identifiers, e.g. "%x.x" no longer possible, should be "%x. x";
  7656 
  7657 * simpset (and claset) reference variable replaced by functions
  7658 simpset / simpset_ref;
  7659 
  7660 * no longer supports theory aliases (via merge) and non-trivial
  7661 implicit merge of thms' signatures;
  7662 
  7663 * most internal names of constants changed due to qualified names;
  7664 
  7665 * changed Pure/Sequence interface (see Pure/seq.ML);
  7666 
  7667 
  7668 *** General Changes ***
  7669 
  7670 * hierachically structured name spaces (for consts, types, axms, thms
  7671 etc.); new lexical class 'longid' (e.g. Foo.bar.x) may render much of
  7672 old input syntactically incorrect (e.g. "%x.x"); COMPATIBILITY:
  7673 isatool fixdots ensures space after dots (e.g. "%x. x"); set
  7674 long_names for fully qualified output names; NOTE: ML programs
  7675 (special tactics, packages etc.) referring to internal names may have
  7676 to be adapted to cope with fully qualified names; in case of severe
  7677 backward campatibility problems try setting 'global_names' at compile
  7678 time to have enrything declared within a flat name space; one may also
  7679 fine tune name declarations in theories via the 'global' and 'local'
  7680 section;
  7681 
  7682 * reimplemented the implicit simpset and claset using the new anytype
  7683 data filed in signatures; references simpset:simpset ref etc. are
  7684 replaced by functions simpset:unit->simpset and
  7685 simpset_ref:unit->simpset ref; COMPATIBILITY: use isatool fixclasimp
  7686 to patch your ML files accordingly;
  7687 
  7688 * HTML output now includes theory graph data for display with Java
  7689 applet or isatool browser; data generated automatically via isatool
  7690 usedir (see -i option, ISABELLE_USEDIR_OPTIONS);
  7691 
  7692 * defs may now be conditional; improved rewrite_goals_tac to handle
  7693 conditional equations;
  7694 
  7695 * defs now admits additional type arguments, using TYPE('a) syntax;
  7696 
  7697 * theory aliases via merge (e.g. M=A+B+C) no longer supported, always
  7698 creates a new theory node; implicit merge of thms' signatures is
  7699 restricted to 'trivial' ones; COMPATIBILITY: one may have to use
  7700 transfer:theory->thm->thm in (rare) cases;
  7701 
  7702 * improved handling of draft signatures / theories; draft thms (and
  7703 ctyps, cterms) are automatically promoted to real ones;
  7704 
  7705 * slightly changed interfaces for oracles: admit many per theory, named
  7706 (e.g. oracle foo = mlfun), additional name argument for invoke_oracle;
  7707 
  7708 * print_goals: optional output of const types (set show_consts and
  7709 show_types);
  7710 
  7711 * improved output of warnings (###) and errors (***);
  7712 
  7713 * subgoal_tac displays a warning if the new subgoal has type variables;
  7714 
  7715 * removed old README and Makefiles;
  7716 
  7717 * replaced print_goals_ref hook by print_current_goals_fn and result_error_fn;
  7718 
  7719 * removed obsolete init_pps and init_database;
  7720 
  7721 * deleted the obsolete tactical STATE, which was declared by
  7722     fun STATE tacfun st = tacfun st st;
  7723 
  7724 * cd and use now support path variables, e.g. $ISABELLE_HOME, or ~
  7725 (which abbreviates $HOME);
  7726 
  7727 * changed Pure/Sequence interface (see Pure/seq.ML); COMPATIBILITY:
  7728 use isatool fixseq to adapt your ML programs (this works for fully
  7729 qualified references to the Sequence structure only!);
  7730 
  7731 * use_thy no longer requires writable current directory; it always
  7732 reloads .ML *and* .thy file, if either one is out of date;
  7733 
  7734 
  7735 *** Classical Reasoner ***
  7736 
  7737 * Clarify_tac, clarify_tac, clarify_step_tac, Clarify_step_tac: new
  7738 tactics that use classical reasoning to simplify a subgoal without
  7739 splitting it into several subgoals;
  7740 
  7741 * Safe_tac: like safe_tac but uses the default claset;
  7742 
  7743 
  7744 *** Simplifier ***
  7745 
  7746 * added simplification meta rules:
  7747     (asm_)(full_)simplify: simpset -> thm -> thm;
  7748 
  7749 * simplifier.ML no longer part of Pure -- has to be loaded by object
  7750 logics (again);
  7751 
  7752 * added prems argument to simplification procedures;
  7753 
  7754 * HOL, FOL, ZF: added infix function `addsplits':
  7755   instead of `<simpset> setloop (split_tac <thms>)'
  7756   you can simply write `<simpset> addsplits <thms>'
  7757 
  7758 
  7759 *** Syntax ***
  7760 
  7761 * TYPE('a) syntax for type reflection terms;
  7762 
  7763 * no longer handles consts with name "" -- declare as 'syntax' instead;
  7764 
  7765 * pretty printer: changed order of mixfix annotation preference (again!);
  7766 
  7767 * Pure: fixed idt/idts vs. pttrn/pttrns syntactic categories;
  7768 
  7769 
  7770 *** HOL ***
  7771 
  7772 * HOL: there is a new splitter `split_asm_tac' that can be used e.g.
  7773   with `addloop' of the simplifier to faciliate case splitting in premises.
  7774 
  7775 * HOL/TLA: Stephan Merz's formalization of Lamport's Temporal Logic of Actions;
  7776 
  7777 * HOL/Auth: new protocol proofs including some for the Internet
  7778   protocol TLS;
  7779 
  7780 * HOL/Map: new theory of `maps' a la VDM;
  7781 
  7782 * HOL/simplifier: simplification procedures nat_cancel_sums for
  7783 cancelling out common nat summands from =, <, <= (in)equalities, or
  7784 differences; simplification procedures nat_cancel_factor for
  7785 cancelling common factor from =, <, <= (in)equalities over natural
  7786 sums; nat_cancel contains both kinds of procedures, it is installed by
  7787 default in Arith.thy -- this COULD MAKE EXISTING PROOFS FAIL;
  7788 
  7789 * HOL/simplifier: terms of the form
  7790   `? x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x)'  (or t=x)
  7791   are rewritten to
  7792   `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t)',
  7793   and those of the form
  7794   `! x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x) --> R(x)'  (or t=x)
  7795   are rewritten to
  7796   `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t) --> R(t)',
  7797 
  7798 * HOL/datatype
  7799   Each datatype `t' now comes with a theorem `split_t_case' of the form
  7800 
  7801   P(t_case f1 ... fn x) =
  7802      ( (!y1 ... ym1. x = C1 y1 ... ym1 --> P(f1 y1 ... ym1)) &
  7803         ...
  7804        (!y1 ... ymn. x = Cn y1 ... ymn --> P(f1 y1 ... ymn))
  7805      )
  7806 
  7807   and a theorem `split_t_case_asm' of the form
  7808 
  7809   P(t_case f1 ... fn x) =
  7810     ~( (? y1 ... ym1. x = C1 y1 ... ym1 & ~P(f1 y1 ... ym1)) |
  7811         ...
  7812        (? y1 ... ymn. x = Cn y1 ... ymn & ~P(f1 y1 ... ymn))
  7813      )
  7814   which can be added to a simpset via `addsplits'. The existing theorems
  7815   expand_list_case and expand_option_case have been renamed to
  7816   split_list_case and split_option_case.
  7817 
  7818 * HOL/Arithmetic:
  7819   - `pred n' is automatically converted to `n-1'.
  7820     Users are strongly encouraged not to use `pred' any longer,
  7821     because it will disappear altogether at some point.
  7822   - Users are strongly encouraged to write "0 < n" rather than
  7823     "n ~= 0". Theorems and proof tools have been modified towards this
  7824     `standard'.
  7825 
  7826 * HOL/Lists:
  7827   the function "set_of_list" has been renamed "set" (and its theorems too);
  7828   the function "nth" now takes its arguments in the reverse order and
  7829   has acquired the infix notation "!" as in "xs!n".
  7830 
  7831 * HOL/Set: UNIV is now a constant and is no longer translated to Compl{};
  7832 
  7833 * HOL/Set: The operator (UN x.B x) now abbreviates (UN x:UNIV. B x) and its
  7834   specialist theorems (like UN1_I) are gone.  Similarly for (INT x.B x);
  7835 
  7836 * HOL/record: extensible records with schematic structural subtyping
  7837 (single inheritance); EXPERIMENTAL version demonstrating the encoding,
  7838 still lacks various theorems and concrete record syntax;
  7839 
  7840 
  7841 *** HOLCF ***
  7842 
  7843 * removed "axioms" and "generated by" sections;
  7844 
  7845 * replaced "ops" section by extended "consts" section, which is capable of
  7846   handling the continuous function space "->" directly;
  7847 
  7848 * domain package:
  7849   . proves theorems immediately and stores them in the theory,
  7850   . creates hierachical name space,
  7851   . now uses normal mixfix annotations (instead of cinfix...),
  7852   . minor changes to some names and values (for consistency),
  7853   . e.g. cases -> casedist, dists_eq -> dist_eqs, [take_lemma] -> take_lemmas,
  7854   . separator between mutual domain defs: changed "," to "and",
  7855   . improved handling of sort constraints;  now they have to
  7856     appear on the left-hand side of the equations only;
  7857 
  7858 * fixed LAM <x,y,zs>.b syntax;
  7859 
  7860 * added extended adm_tac to simplifier in HOLCF -- can now discharge
  7861 adm (%x. P (t x)), where P is chainfinite and t continuous;
  7862 
  7863 
  7864 *** FOL and ZF ***
  7865 
  7866 * FOL: there is a new splitter `split_asm_tac' that can be used e.g.
  7867   with `addloop' of the simplifier to faciliate case splitting in premises.
  7868 
  7869 * qed_spec_mp, qed_goal_spec_mp, qed_goalw_spec_mp are available, as
  7870 in HOL, they strip ALL and --> from proved theorems;
  7871 
  7872 
  7873 
  7874 New in Isabelle94-8 (May 1997)
  7875 ------------------------------
  7876 
  7877 *** General Changes ***
  7878 
  7879 * new utilities to build / run / maintain Isabelle etc. (in parts
  7880 still somewhat experimental); old Makefiles etc. still functional;
  7881 
  7882 * new 'Isabelle System Manual';
  7883 
  7884 * INSTALL text, together with ./configure and ./build scripts;
  7885 
  7886 * reimplemented type inference for greater efficiency, better error
  7887 messages and clean internal interface;
  7888 
  7889 * prlim command for dealing with lots of subgoals (an easier way of
  7890 setting goals_limit);
  7891 
  7892 
  7893 *** Syntax ***
  7894 
  7895 * supports alternative (named) syntax tables (parser and pretty
  7896 printer); internal interface is provided by add_modesyntax(_i);
  7897 
  7898 * Pure, FOL, ZF, HOL, HOLCF now support symbolic input and output; to
  7899 be used in conjunction with the Isabelle symbol font; uses the
  7900 "symbols" syntax table;
  7901 
  7902 * added token_translation interface (may translate name tokens in
  7903 arbitrary ways, dependent on their type (free, bound, tfree, ...) and
  7904 the current print_mode); IMPORTANT: user print translation functions
  7905 are responsible for marking newly introduced bounds
  7906 (Syntax.mark_boundT);
  7907 
  7908 * token translations for modes "xterm" and "xterm_color" that display
  7909 names in bold, underline etc. or colors (which requires a color
  7910 version of xterm);
  7911 
  7912 * infixes may now be declared with names independent of their syntax;
  7913 
  7914 * added typed_print_translation (like print_translation, but may
  7915 access type of constant);
  7916 
  7917 
  7918 *** Classical Reasoner ***
  7919 
  7920 Blast_tac: a new tactic!  It is often more powerful than fast_tac, but has
  7921 some limitations.  Blast_tac...
  7922   + ignores addss, addbefore, addafter; this restriction is intrinsic
  7923   + ignores elimination rules that don't have the correct format
  7924         (the conclusion MUST be a formula variable)
  7925   + ignores types, which can make HOL proofs fail
  7926   + rules must not require higher-order unification, e.g. apply_type in ZF
  7927     [message "Function Var's argument not a bound variable" relates to this]
  7928   + its proof strategy is more general but can actually be slower
  7929 
  7930 * substitution with equality assumptions no longer permutes other
  7931 assumptions;
  7932 
  7933 * minor changes in semantics of addafter (now called addaltern); renamed
  7934 setwrapper to setWrapper and compwrapper to compWrapper; added safe wrapper
  7935 (and access functions for it);
  7936 
  7937 * improved combination of classical reasoner and simplifier:
  7938   + functions for handling clasimpsets
  7939   + improvement of addss: now the simplifier is called _after_ the
  7940     safe steps.
  7941   + safe variant of addss called addSss: uses safe simplifications
  7942     _during_ the safe steps. It is more complete as it allows multiple
  7943     instantiations of unknowns (e.g. with slow_tac).
  7944 
  7945 *** Simplifier ***
  7946 
  7947 * added interface for simplification procedures (functions that
  7948 produce *proven* rewrite rules on the fly, depending on current
  7949 redex);
  7950 
  7951 * ordering on terms as parameter (used for ordered rewriting);
  7952 
  7953 * new functions delcongs, deleqcongs, and Delcongs. richer rep_ss;
  7954 
  7955 * the solver is now split into a safe and an unsafe part.
  7956 This should be invisible for the normal user, except that the
  7957 functions setsolver and addsolver have been renamed to setSolver and
  7958 addSolver; added safe_asm_full_simp_tac;
  7959 
  7960 
  7961 *** HOL ***
  7962 
  7963 * a generic induction tactic `induct_tac' which works for all datatypes and
  7964 also for type `nat';
  7965 
  7966 * a generic case distinction tactic `exhaust_tac' which works for all
  7967 datatypes and also for type `nat';
  7968 
  7969 * each datatype comes with a function `size';
  7970 
  7971 * patterns in case expressions allow tuple patterns as arguments to
  7972 constructors, for example `case x of [] => ... | (x,y,z)#ps => ...';
  7973 
  7974 * primrec now also works with type nat;
  7975 
  7976 * recdef: a new declaration form, allows general recursive functions to be
  7977 defined in theory files.  See HOL/ex/Fib, HOL/ex/Primes, HOL/Subst/Unify.
  7978 
  7979 * the constant for negation has been renamed from "not" to "Not" to
  7980 harmonize with FOL, ZF, LK, etc.;
  7981 
  7982 * HOL/ex/LFilter theory of a corecursive "filter" functional for
  7983 infinite lists;
  7984 
  7985 * HOL/Modelcheck demonstrates invocation of model checker oracle;
  7986 
  7987 * HOL/ex/Ring.thy declares cring_simp, which solves equational
  7988 problems in commutative rings, using axiomatic type classes for + and *;
  7989 
  7990 * more examples in HOL/MiniML and HOL/Auth;
  7991 
  7992 * more default rewrite rules for quantifiers, union/intersection;
  7993 
  7994 * a new constant `arbitrary == @x.False';
  7995 
  7996 * HOLCF/IOA replaces old HOL/IOA;
  7997 
  7998 * HOLCF changes: derived all rules and arities
  7999   + axiomatic type classes instead of classes
  8000   + typedef instead of faking type definitions
  8001   + eliminated the internal constants less_fun, less_cfun, UU_fun, UU_cfun etc.
  8002   + new axclasses cpo, chfin, flat with flat < chfin < pcpo < cpo < po
  8003   + eliminated the types void, one, tr
  8004   + use unit lift and bool lift (with translations) instead of one and tr
  8005   + eliminated blift from Lift3.thy (use Def instead of blift)
  8006   all eliminated rules are derived as theorems --> no visible changes ;
  8007 
  8008 
  8009 *** ZF ***
  8010 
  8011 * ZF now has Fast_tac, Simp_tac and Auto_tac.  Union_iff is a now a default
  8012 rewrite rule; this may affect some proofs.  eq_cs is gone but can be put back
  8013 as ZF_cs addSIs [equalityI];
  8014 
  8015 
  8016 
  8017 New in Isabelle94-7 (November 96)
  8018 ---------------------------------
  8019 
  8020 * allowing negative levels (as offsets) in prlev and choplev;
  8021 
  8022 * super-linear speedup for large simplifications;
  8023 
  8024 * FOL, ZF and HOL now use miniscoping: rewriting pushes
  8025 quantifications in as far as possible (COULD MAKE EXISTING PROOFS
  8026 FAIL); can suppress it using the command Delsimps (ex_simps @
  8027 all_simps); De Morgan laws are also now included, by default;
  8028 
  8029 * improved printing of ==>  :  ~:
  8030 
  8031 * new object-logic "Sequents" adds linear logic, while replacing LK
  8032 and Modal (thanks to Sara Kalvala);
  8033 
  8034 * HOL/Auth: correctness proofs for authentication protocols;
  8035 
  8036 * HOL: new auto_tac combines rewriting and classical reasoning (many
  8037 examples on HOL/Auth);
  8038 
  8039 * HOL: new command AddIffs for declaring theorems of the form P=Q to
  8040 the rewriter and classical reasoner simultaneously;
  8041 
  8042 * function uresult no longer returns theorems in "standard" format;
  8043 regain previous version by: val uresult = standard o uresult;
  8044 
  8045 
  8046 
  8047 New in Isabelle94-6
  8048 -------------------
  8049 
  8050 * oracles -- these establish an interface between Isabelle and trusted
  8051 external reasoners, which may deliver results as theorems;
  8052 
  8053 * proof objects (in particular record all uses of oracles);
  8054 
  8055 * Simp_tac, Fast_tac, etc. that refer to implicit simpset / claset;
  8056 
  8057 * "constdefs" section in theory files;
  8058 
  8059 * "primrec" section (HOL) no longer requires names;
  8060 
  8061 * internal type "tactic" now simply "thm -> thm Sequence.seq";
  8062 
  8063 
  8064 
  8065 New in Isabelle94-5
  8066 -------------------
  8067 
  8068 * reduced space requirements;
  8069 
  8070 * automatic HTML generation from theories;
  8071 
  8072 * theory files no longer require "..." (quotes) around most types;
  8073 
  8074 * new examples, including two proofs of the Church-Rosser theorem;
  8075 
  8076 * non-curried (1994) version of HOL is no longer distributed;
  8077 
  8078 
  8079 
  8080 New in Isabelle94-4
  8081 -------------------
  8082 
  8083 * greatly reduced space requirements;
  8084 
  8085 * theory files (.thy) no longer require \...\ escapes at line breaks;
  8086 
  8087 * searchable theorem database (see the section "Retrieving theorems" on
  8088 page 8 of the Reference Manual);
  8089 
  8090 * new examples, including Grabczewski's monumental case study of the
  8091 Axiom of Choice;
  8092 
  8093 * The previous version of HOL renamed to Old_HOL;
  8094 
  8095 * The new version of HOL (previously called CHOL) uses a curried syntax
  8096 for functions.  Application looks like f a b instead of f(a,b);
  8097 
  8098 * Mutually recursive inductive definitions finally work in HOL;
  8099 
  8100 * In ZF, pattern-matching on tuples is now available in all abstractions and
  8101 translates to the operator "split";
  8102 
  8103 
  8104 
  8105 New in Isabelle94-3
  8106 -------------------
  8107 
  8108 * new infix operator, addss, allowing the classical reasoner to
  8109 perform simplification at each step of its search.  Example:
  8110         fast_tac (cs addss ss)
  8111 
  8112 * a new logic, CHOL, the same as HOL, but with a curried syntax
  8113 for functions.  Application looks like f a b instead of f(a,b).  Also pairs
  8114 look like (a,b) instead of <a,b>;
  8115 
  8116 * PLEASE NOTE: CHOL will eventually replace HOL!
  8117 
  8118 * In CHOL, pattern-matching on tuples is now available in all abstractions.
  8119 It translates to the operator "split".  A new theory of integers is available;
  8120 
  8121 * In ZF, integer numerals now denote two's-complement binary integers.
  8122 Arithmetic operations can be performed by rewriting.  See ZF/ex/Bin.ML;
  8123 
  8124 * Many new examples: I/O automata, Church-Rosser theorem, equivalents
  8125 of the Axiom of Choice;
  8126 
  8127 
  8128 
  8129 New in Isabelle94-2
  8130 -------------------
  8131 
  8132 * Significantly faster resolution;
  8133 
  8134 * the different sections in a .thy file can now be mixed and repeated
  8135 freely;
  8136 
  8137 * Database of theorems for FOL, HOL and ZF.  New
  8138 commands including qed, qed_goal and bind_thm store theorems in the database.
  8139 
  8140 * Simple database queries: return a named theorem (get_thm) or all theorems of
  8141 a given theory (thms_of), or find out what theory a theorem was proved in
  8142 (theory_of_thm);
  8143 
  8144 * Bugs fixed in the inductive definition and datatype packages;
  8145 
  8146 * The classical reasoner provides deepen_tac and depth_tac, making FOL_dup_cs
  8147 and HOL_dup_cs obsolete;
  8148 
  8149 * Syntactic ambiguities caused by the new treatment of syntax in Isabelle94-1
  8150 have been removed;
  8151 
  8152 * Simpler definition of function space in ZF;
  8153 
  8154 * new results about cardinal and ordinal arithmetic in ZF;
  8155 
  8156 * 'subtype' facility in HOL for introducing new types as subsets of existing
  8157 types;
  8158 
  8159 :mode=text:wrap=hard:maxLineLen=72: