NEWS
author wenzelm
Sat Apr 16 22:21:34 2011 +0200 (2011-04-16)
changeset 42370 244911efd275
parent 42360 da8817d01e7c
child 42403 38b29c9fc742
permissions -rw-r--r--
refined PARALLEL_GOALS;
     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 * Name space: proper configuration options "long_names",
    41 "short_names", "unique_names" instead of former unsynchronized
    42 references.  Minor INCOMPATIBILITY, need to declare options in context
    43 like this:
    44 
    45   declare [[unique_names = false]]
    46 
    47 
    48 *** HOL ***
    49 
    50 * Nitpick:
    51   - Added "need" and "total_consts" options.
    52   - Reintroduced "show_skolems" option by popular demand.
    53   - Renamed attribute: nitpick_def ~> nitpick_unfold.
    54     INCOMPATIBILITY.
    55 
    56 * Sledgehammer:
    57   - sledgehammer available_provers ~> sledgehammer supported_provers
    58     INCOMPATIBILITY.
    59   - Added "monomorphize", "monomorphize_limit", and "type_sys" options.
    60 
    61 * "try":
    62   - Added "simp:", "intro:", and "elim:" options.
    63 
    64 * Quickcheck:
    65   - Added "eval" option to evaluate terms for the found counterexample
    66     (currently only supported by the default (exhaustive) tester)
    67   - Added post-processing of terms to obtain readable counterexamples
    68     (currently only supported by the default (exhaustive) tester)
    69 
    70 * Function package: discontinued option "tailrec".
    71 INCOMPATIBILITY. Use partial_function instead.
    72 
    73 * HOL-Probability:
    74   - Caratheodory's extension lemma is now proved for ring_of_sets.
    75   - Infinite products of probability measures are now available.
    76   - Use extended reals instead of positive extended reals.
    77     INCOMPATIBILITY.
    78 
    79 *** Document preparation ***
    80 
    81 * New term style "isub" as ad-hoc conversion of variables x1, y23 into
    82 subscripted form x\<^isub>1, y\<^isub>2\<^isub>3.
    83 
    84 
    85 *** ML ***
    86 
    87 * Structure Proof_Context follows standard naming scheme.  Old
    88 ProofContext is still available for some time as legacy alias.
    89 
    90 * Structure Timing provides various operations for timing; supersedes
    91 former start_timing/end_timing etc.
    92 
    93 * Path.print is the official way to show file-system paths to users
    94 (including quotes etc.).
    95 
    96 * Inner syntax: identifiers in parse trees of generic categories
    97 "logic", "aprop", "idt" etc. carry position information (disguised as
    98 type constraints).  Occasional INCOMPATIBILITY with non-compliant
    99 translations that choke on unexpected type constraints.  Positions can
   100 be stripped in ML translations via Syntax.strip_positions /
   101 Syntax.strip_positions_ast, or via the syntax constant
   102 "_strip_positions" within parse trees.  As last resort, positions can
   103 be disabled via the configuration option Syntax.positions, which is
   104 called "syntax_positions" in Isar attribute syntax.
   105 
   106 * Discontinued special status of various ML structures that contribute
   107 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
   108 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
   109 refer directly to Ast.Constant, Lexicon.is_identifier,
   110 Syntax_Trans.mk_binder_tr etc.
   111 
   112 * Typed print translation: discontinued show_sorts argument, which is
   113 already available via context of "advanced" translation.
   114 
   115 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
   116 goal states; body tactic needs to address all subgoals uniformly.
   117 
   118 
   119 
   120 New in Isabelle2011 (January 2011)
   121 ----------------------------------
   122 
   123 *** General ***
   124 
   125 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
   126 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
   127 useful tooltips and hyperlinks produced from its static analysis.  The
   128 bundled component provides an executable Isabelle tool that can be run
   129 like this:
   130 
   131   Isabelle2011/bin/isabelle jedit
   132 
   133 * Significantly improved Isabelle/Isar implementation manual.
   134 
   135 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
   136 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
   137 while the default heap location within that directory lacks that extra
   138 suffix.  This isolates multiple Isabelle installations from each
   139 other, avoiding problems with old settings in new versions.
   140 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
   141 
   142 * Source files are always encoded as UTF-8, instead of old-fashioned
   143 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
   144 the following package declarations:
   145 
   146   \usepackage[utf8]{inputenc}
   147   \usepackage{textcomp}
   148 
   149 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
   150 a Unicode character is treated as a single symbol, not a sequence of
   151 non-ASCII bytes as before.  Since Isabelle/ML string literals may
   152 contain symbols without further backslash escapes, Unicode can now be
   153 used here as well.  Recall that Symbol.explode in ML provides a
   154 consistent view on symbols, while raw explode (or String.explode)
   155 merely give a byte-oriented representation.
   156 
   157 * Theory loader: source files are primarily located via the master
   158 directory of each theory node (where the .thy file itself resides).
   159 The global load path is still partially available as legacy feature.
   160 Minor INCOMPATIBILITY due to subtle change in file lookup: use
   161 explicit paths, relatively to the theory.
   162 
   163 * Special treatment of ML file names has been discontinued.
   164 Historically, optional extensions .ML or .sml were added on demand --
   165 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
   166 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
   167 
   168 * Various options that affect pretty printing etc. are now properly
   169 handled within the context via configuration options, instead of
   170 unsynchronized references or print modes.  There are both ML Config.T
   171 entities and Isar declaration attributes to access these.
   172 
   173   ML (Config.T)                 Isar (attribute)
   174 
   175   eta_contract                  eta_contract
   176   show_brackets                 show_brackets
   177   show_sorts                    show_sorts
   178   show_types                    show_types
   179   show_question_marks           show_question_marks
   180   show_consts                   show_consts
   181   show_abbrevs                  show_abbrevs
   182 
   183   Syntax.ast_trace              syntax_ast_trace
   184   Syntax.ast_stat               syntax_ast_stat
   185   Syntax.ambiguity_level        syntax_ambiguity_level
   186 
   187   Goal_Display.goals_limit      goals_limit
   188   Goal_Display.show_main_goal   show_main_goal
   189 
   190   Method.rule_trace             rule_trace
   191 
   192   Thy_Output.display            thy_output_display
   193   Thy_Output.quotes             thy_output_quotes
   194   Thy_Output.indent             thy_output_indent
   195   Thy_Output.source             thy_output_source
   196   Thy_Output.break              thy_output_break
   197 
   198 Note that corresponding "..._default" references in ML may only be
   199 changed globally at the ROOT session setup, but *not* within a theory.
   200 The option "show_abbrevs" supersedes the former print mode
   201 "no_abbrevs" with inverted meaning.
   202 
   203 * More systematic naming of some configuration options.
   204 INCOMPATIBILITY.
   205 
   206   trace_simp  ~>  simp_trace
   207   debug_simp  ~>  simp_debug
   208 
   209 * Support for real valued configuration options, using simplistic
   210 floating-point notation that coincides with the inner syntax for
   211 float_token.
   212 
   213 * Support for real valued preferences (with approximative PGIP type):
   214 front-ends need to accept "pgint" values in float notation.
   215 INCOMPATIBILITY.
   216 
   217 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
   218 DejaVu Sans.
   219 
   220 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   221 
   222 
   223 *** Pure ***
   224 
   225 * Command 'type_synonym' (with single argument) replaces somewhat
   226 outdated 'types', which is still available as legacy feature for some
   227 time.
   228 
   229 * Command 'nonterminal' (with 'and' separated list of arguments)
   230 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
   231 
   232 * Command 'notepad' replaces former 'example_proof' for
   233 experimentation in Isar without any result.  INCOMPATIBILITY.
   234 
   235 * Locale interpretation commands 'interpret' and 'sublocale' accept
   236 lists of equations to map definitions in a locale to appropriate
   237 entities in the context of the interpretation.  The 'interpretation'
   238 command already provided this functionality.
   239 
   240 * Diagnostic command 'print_dependencies' prints the locale instances
   241 that would be activated if the specified expression was interpreted in
   242 the current context.  Variant "print_dependencies!" assumes a context
   243 without interpretations.
   244 
   245 * Diagnostic command 'print_interps' prints interpretations in proofs
   246 in addition to interpretations in theories.
   247 
   248 * Discontinued obsolete 'global' and 'local' commands to manipulate
   249 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
   250 Sign.root_path and Sign.local_path may be applied directly where this
   251 feature is still required for historical reasons.
   252 
   253 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
   254 'definition' instead.
   255 
   256 * The "prems" fact, which refers to the accidental collection of
   257 foundational premises in the context, is now explicitly marked as
   258 legacy feature and will be discontinued soon.  Consider using "assms"
   259 of the head statement or reference facts by explicit names.
   260 
   261 * Document antiquotations @{class} and @{type} print classes and type
   262 constructors.
   263 
   264 * Document antiquotation @{file} checks file/directory entries within
   265 the local file system.
   266 
   267 
   268 *** HOL ***
   269 
   270 * Coercive subtyping: functions can be declared as coercions and type
   271 inference will add them as necessary upon input of a term.  Theory
   272 Complex_Main declares real :: nat => real and real :: int => real as
   273 coercions. A coercion function f is declared like this:
   274 
   275   declare [[coercion f]]
   276 
   277 To lift coercions through type constructors (e.g. from nat => real to
   278 nat list => real list), map functions can be declared, e.g.
   279 
   280   declare [[coercion_map map]]
   281 
   282 Currently coercion inference is activated only in theories including
   283 real numbers, i.e. descendants of Complex_Main.  This is controlled by
   284 the configuration option "coercion_enabled", e.g. it can be enabled in
   285 other theories like this:
   286 
   287   declare [[coercion_enabled]]
   288 
   289 * Command 'partial_function' provides basic support for recursive
   290 function definitions over complete partial orders.  Concrete instances
   291 are provided for i) the option type, ii) tail recursion on arbitrary
   292 types, and iii) the heap monad of Imperative_HOL.  See
   293 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
   294 for examples.
   295 
   296 * Function package: f.psimps rules are no longer implicitly declared
   297 as [simp].  INCOMPATIBILITY.
   298 
   299 * Datatype package: theorems generated for executable equality (class
   300 "eq") carry proper names and are treated as default code equations.
   301 
   302 * Inductive package: now offers command 'inductive_simps' to
   303 automatically derive instantiated and simplified equations for
   304 inductive predicates, similar to 'inductive_cases'.
   305 
   306 * Command 'enriched_type' allows to register properties of the
   307 functorial structure of types.
   308 
   309 * Improved infrastructure for term evaluation using code generator
   310 techniques, in particular static evaluation conversions.
   311 
   312 * Code generator: Scala (2.8 or higher) has been added to the target
   313 languages.
   314 
   315 * Code generator: globbing constant expressions "*" and "Theory.*"
   316 have been replaced by the more idiomatic "_" and "Theory._".
   317 INCOMPATIBILITY.
   318 
   319 * Code generator: export_code without explicit file declaration prints
   320 to standard output.  INCOMPATIBILITY.
   321 
   322 * Code generator: do not print function definitions for case
   323 combinators any longer.
   324 
   325 * Code generator: simplification with rules determined with
   326 src/Tools/Code/code_simp.ML and method "code_simp".
   327 
   328 * Code generator for records: more idiomatic representation of record
   329 types.  Warning: records are not covered by ancient SML code
   330 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
   331 rep_datatype declaration helps to succeed then:
   332 
   333   record 'a foo = ...
   334   ...
   335   rep_datatype foo_ext ...
   336 
   337 * Records: logical foundation type for records does not carry a
   338 '_type' suffix any longer (obsolete due to authentic syntax).
   339 INCOMPATIBILITY.
   340 
   341 * Quickcheck now by default uses exhaustive testing instead of random
   342 testing.  Random testing can be invoked by "quickcheck [random]",
   343 exhaustive testing by "quickcheck [exhaustive]".
   344 
   345 * Quickcheck instantiates polymorphic types with small finite
   346 datatypes by default. This enables a simple execution mechanism to
   347 handle quantifiers and function equality over the finite datatypes.
   348 
   349 * Quickcheck random generator has been renamed from "code" to
   350 "random".  INCOMPATIBILITY.
   351 
   352 * Quickcheck now has a configurable time limit which is set to 30
   353 seconds by default. This can be changed by adding [timeout = n] to the
   354 quickcheck command. The time limit for Auto Quickcheck is still set
   355 independently.
   356 
   357 * Quickcheck in locales considers interpretations of that locale for
   358 counter example search.
   359 
   360 * Sledgehammer:
   361   - Added "smt" and "remote_smt" provers based on the "smt" proof
   362     method. See the Sledgehammer manual for details ("isabelle doc
   363     sledgehammer").
   364   - Renamed commands:
   365     sledgehammer atp_info ~> sledgehammer running_provers
   366     sledgehammer atp_kill ~> sledgehammer kill_provers
   367     sledgehammer available_atps ~> sledgehammer available_provers
   368     INCOMPATIBILITY.
   369   - Renamed options:
   370     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
   371     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
   372     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
   373     (and "ms" and "min" are no longer supported)
   374     INCOMPATIBILITY.
   375 
   376 * Nitpick:
   377   - Renamed options:
   378     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
   379     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
   380     INCOMPATIBILITY.
   381   - Added support for partial quotient types.
   382   - Added local versions of the "Nitpick.register_xxx" functions.
   383   - Added "whack" option.
   384   - Allow registration of quotient types as codatatypes.
   385   - Improved "merge_type_vars" option to merge more types.
   386   - Removed unsound "fast_descrs" option.
   387   - Added custom symmetry breaking for datatypes, making it possible to reach
   388     higher cardinalities.
   389   - Prevent the expansion of too large definitions.
   390 
   391 * Proof methods "metis" and "meson" now have configuration options
   392 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
   393 to diagnose these tools. E.g.
   394 
   395     using [[metis_trace = true]]
   396 
   397 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
   398 manually as command 'solve_direct'.
   399 
   400 * The default SMT solver Z3 must be enabled explicitly (due to
   401 licensing issues) by setting the environment variable
   402 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
   403 commercial applications, the SMT solver CVC3 is provided as fall-back;
   404 changing the SMT solver is done via the configuration option
   405 "smt_solver".
   406 
   407 * Remote SMT solvers need to be referred to by the "remote_" prefix,
   408 i.e. "remote_cvc3" and "remote_z3".
   409 
   410 * Added basic SMT support for datatypes, records, and typedefs using
   411 the oracle mode (no proofs).  Direct support of pairs has been dropped
   412 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
   413 support for a similar behavior).  Minor INCOMPATIBILITY.
   414 
   415 * Changed SMT configuration options:
   416   - Renamed:
   417     z3_proofs ~> smt_oracle (with inverted meaning)
   418     z3_trace_assms ~> smt_trace_used_facts
   419     INCOMPATIBILITY.
   420   - Added:
   421     smt_verbose
   422     smt_random_seed
   423     smt_datatypes
   424     smt_infer_triggers
   425     smt_monomorph_limit
   426     cvc3_options
   427     remote_cvc3_options
   428     remote_z3_options
   429     yices_options
   430 
   431 * Boogie output files (.b2i files) need to be declared in the theory
   432 header.
   433 
   434 * Simplification procedure "list_to_set_comprehension" rewrites list
   435 comprehensions applied to List.set to set comprehensions.  Occasional
   436 INCOMPATIBILITY, may be deactivated like this:
   437 
   438   declare [[simproc del: list_to_set_comprehension]]
   439 
   440 * Removed old version of primrec package.  INCOMPATIBILITY.
   441 
   442 * Removed simplifier congruence rule of "prod_case", as has for long
   443 been the case with "split".  INCOMPATIBILITY.
   444 
   445 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
   446 
   447 * Removed [split_format ... and ... and ...] version of
   448 [split_format].  Potential INCOMPATIBILITY.
   449 
   450 * Predicate "sorted" now defined inductively, with nice induction
   451 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
   452 
   453 * Constant "contents" renamed to "the_elem", to free the generic name
   454 contents for other uses.  INCOMPATIBILITY.
   455 
   456 * Renamed class eq and constant eq (for code generation) to class
   457 equal and constant equal, plus renaming of related facts and various
   458 tuning.  INCOMPATIBILITY.
   459 
   460 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
   461 
   462 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
   463 INCOMPATIBILITY.
   464 
   465 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
   466 avoid confusion with finite sets.  INCOMPATIBILITY.
   467 
   468 * Abandoned locales equiv, congruent and congruent2 for equivalence
   469 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
   470 for congruent(2)).
   471 
   472 * Some previously unqualified names have been qualified:
   473 
   474   types
   475     bool ~> HOL.bool
   476     nat ~> Nat.nat
   477 
   478   constants
   479     Trueprop ~> HOL.Trueprop
   480     True ~> HOL.True
   481     False ~> HOL.False
   482     op & ~> HOL.conj
   483     op | ~> HOL.disj
   484     op --> ~> HOL.implies
   485     op = ~> HOL.eq
   486     Not ~> HOL.Not
   487     The ~> HOL.The
   488     All ~> HOL.All
   489     Ex ~> HOL.Ex
   490     Ex1 ~> HOL.Ex1
   491     Let ~> HOL.Let
   492     If ~> HOL.If
   493     Ball ~> Set.Ball
   494     Bex ~> Set.Bex
   495     Suc ~> Nat.Suc
   496     Pair ~> Product_Type.Pair
   497     fst ~> Product_Type.fst
   498     snd ~> Product_Type.snd
   499     curry ~> Product_Type.curry
   500     op : ~> Set.member
   501     Collect ~> Set.Collect
   502 
   503 INCOMPATIBILITY.
   504 
   505 * More canonical naming convention for some fundamental definitions:
   506 
   507     bot_bool_eq ~> bot_bool_def
   508     top_bool_eq ~> top_bool_def
   509     inf_bool_eq ~> inf_bool_def
   510     sup_bool_eq ~> sup_bool_def
   511     bot_fun_eq  ~> bot_fun_def
   512     top_fun_eq  ~> top_fun_def
   513     inf_fun_eq  ~> inf_fun_def
   514     sup_fun_eq  ~> sup_fun_def
   515 
   516 INCOMPATIBILITY.
   517 
   518 * More stylized fact names:
   519 
   520   expand_fun_eq ~> fun_eq_iff
   521   expand_set_eq ~> set_eq_iff
   522   set_ext       ~> set_eqI
   523   nat_number    ~> eval_nat_numeral
   524 
   525 INCOMPATIBILITY.
   526 
   527 * Refactoring of code-generation specific operations in theory List:
   528 
   529   constants
   530     null ~> List.null
   531 
   532   facts
   533     mem_iff ~> member_def
   534     null_empty ~> null_def
   535 
   536 INCOMPATIBILITY.  Note that these were not supposed to be used
   537 regularly unless for striking reasons; their main purpose was code
   538 generation.
   539 
   540 Various operations from the Haskell prelude are used for generating
   541 Haskell code.
   542 
   543 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
   544 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
   545 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
   546 
   547 * Abolished some non-alphabetic type names: "prod" and "sum" replace
   548 "*" and "+" respectively.  INCOMPATIBILITY.
   549 
   550 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
   551 "Sum_Type.Plus" instead.
   552 
   553 * Constant "split" has been merged with constant "prod_case"; names of
   554 ML functions, facts etc. involving split have been retained so far,
   555 though.  INCOMPATIBILITY.
   556 
   557 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
   558 instead.  INCOMPATIBILITY.
   559 
   560 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
   561 INCOMPATIBILITY.
   562 
   563 * Former theory Library/Enum is now part of the HOL-Main image.
   564 INCOMPATIBILITY: all constants of the Enum theory now have to be
   565 referred to by its qualified name.
   566 
   567   enum    ~>  Enum.enum
   568   nlists  ~>  Enum.nlists
   569   product ~>  Enum.product
   570 
   571 * Theory Library/Monad_Syntax provides do-syntax for monad types.
   572 Syntax in Library/State_Monad has been changed to avoid ambiguities.
   573 INCOMPATIBILITY.
   574 
   575 * Theory Library/SetsAndFunctions has been split into
   576 Library/Function_Algebras and Library/Set_Algebras; canonical names
   577 for instance definitions for functions; various improvements.
   578 INCOMPATIBILITY.
   579 
   580 * Theory Library/Multiset provides stable quicksort implementation of
   581 sort_key.
   582 
   583 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
   584 INCOMPATIBILITY.
   585 
   586 * Session Multivariate_Analysis: introduced a type class for euclidean
   587 space.  Most theorems are now stated in terms of euclidean spaces
   588 instead of finite cartesian products.
   589 
   590   types
   591     real ^ 'n ~>  'a::real_vector
   592               ~>  'a::euclidean_space
   593               ~>  'a::ordered_euclidean_space
   594         (depends on your needs)
   595 
   596   constants
   597      _ $ _        ~> _ $$ _
   598      \<chi> x. _  ~> \<chi>\<chi> x. _
   599      CARD('n)     ~> DIM('a)
   600 
   601 Also note that the indices are now natural numbers and not from some
   602 finite type. Finite cartesian products of euclidean spaces, products
   603 of euclidean spaces the real and complex numbers are instantiated to
   604 be euclidean_spaces.  INCOMPATIBILITY.
   605 
   606 * Session Probability: introduced pextreal as positive extended real
   607 numbers.  Use pextreal as value for measures.  Introduce the
   608 Radon-Nikodym derivative, product spaces and Fubini's theorem for
   609 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
   610 the integral in Multivariate Analysis.  INCOMPATIBILITY.
   611 
   612 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   613 INCOMPATIBILITY.
   614 
   615 * Session SPARK (with image HOL-SPARK) provides commands to load and
   616 prove verification conditions generated by the SPARK Ada program
   617 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
   618 
   619 
   620 *** HOL-Algebra ***
   621 
   622 * Theorems for additive ring operations (locale abelian_monoid and
   623 descendants) are generated by interpretation from their multiplicative
   624 counterparts.  Names (in particular theorem names) have the mandatory
   625 qualifier 'add'.  Previous theorem names are redeclared for
   626 compatibility.
   627 
   628 * Structure "int_ring" is now an abbreviation (previously a
   629 definition).  This fits more natural with advanced interpretations.
   630 
   631 
   632 *** HOLCF ***
   633 
   634 * The domain package now runs in definitional mode by default: The
   635 former command 'new_domain' is now called 'domain'.  To use the domain
   636 package in its original axiomatic mode, use 'domain (unsafe)'.
   637 INCOMPATIBILITY.
   638 
   639 * The new class "domain" is now the default sort.  Class "predomain"
   640 is an unpointed version of "domain". Theories can be updated by
   641 replacing sort annotations as shown below.  INCOMPATIBILITY.
   642 
   643   'a::type ~> 'a::countable
   644   'a::cpo  ~> 'a::predomain
   645   'a::pcpo ~> 'a::domain
   646 
   647 * The old type class "rep" has been superseded by class "domain".
   648 Accordingly, users of the definitional package must remove any
   649 "default_sort rep" declarations.  INCOMPATIBILITY.
   650 
   651 * The domain package (definitional mode) now supports unpointed
   652 predomain argument types, as long as they are marked 'lazy'. (Strict
   653 arguments must be in class "domain".) For example, the following
   654 domain definition now works:
   655 
   656   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
   657 
   658 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
   659 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
   660 'a option, and 'a list.  Additionally, it configures fixrec and the
   661 domain package to work with these types.  For example:
   662 
   663   fixrec isInl :: "('a + 'b) u -> tr"
   664     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
   665 
   666   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
   667 
   668 * The "(permissive)" option of fixrec has been replaced with a
   669 per-equation "(unchecked)" option. See
   670 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
   671 
   672 * The "bifinite" class no longer fixes a constant "approx"; the class
   673 now just asserts that such a function exists.  INCOMPATIBILITY.
   674 
   675 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
   676 defines an embedding of type 'a defl into udom by default; instances
   677 of "bifinite" and "domain" classes are available in
   678 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
   679 
   680 * The syntax "REP('a)" has been replaced with "DEFL('a)".
   681 
   682 * The predicate "directed" has been removed.  INCOMPATIBILITY.
   683 
   684 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
   685 
   686 * The function "cprod_map" has been renamed to "prod_map".
   687 INCOMPATIBILITY.
   688 
   689 * The monadic bind operator on each powerdomain has new binder syntax
   690 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
   691 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
   692 
   693 * The infix syntax for binary union on each powerdomain has changed
   694 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
   695 syntax.  INCOMPATIBILITY.
   696 
   697 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
   698 still supported as an input translation.
   699 
   700 * Renamed some theorems (the original names are also still available).
   701 
   702   expand_fun_below   ~> fun_below_iff
   703   below_fun_ext      ~> fun_belowI
   704   expand_cfun_eq     ~> cfun_eq_iff
   705   ext_cfun           ~> cfun_eqI
   706   expand_cfun_below  ~> cfun_below_iff
   707   below_cfun_ext     ~> cfun_belowI
   708   cont2cont_Rep_CFun ~> cont2cont_APP
   709 
   710 * The Abs and Rep functions for various types have changed names.
   711 Related theorem names have also changed to match. INCOMPATIBILITY.
   712 
   713   Rep_CFun  ~> Rep_cfun
   714   Abs_CFun  ~> Abs_cfun
   715   Rep_Sprod ~> Rep_sprod
   716   Abs_Sprod ~> Abs_sprod
   717   Rep_Ssum  ~> Rep_ssum
   718   Abs_Ssum  ~> Abs_ssum
   719 
   720 * Lemmas with names of the form *_defined_iff or *_strict_iff have
   721 been renamed to *_bottom_iff.  INCOMPATIBILITY.
   722 
   723 * Various changes to bisimulation/coinduction with domain package:
   724 
   725   - Definitions of "bisim" constants no longer mention definedness.
   726   - With mutual recursion, "bisim" predicate is now curried.
   727   - With mutual recursion, each type gets a separate coind theorem.
   728   - Variable names in bisim_def and coinduct rules have changed.
   729 
   730 INCOMPATIBILITY.
   731 
   732 * Case combinators generated by the domain package for type "foo" are
   733 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
   734 
   735 * Several theorems have been renamed to more accurately reflect the
   736 names of constants and types involved.  INCOMPATIBILITY.
   737 
   738   thelub_const    ~> lub_const
   739   lub_const       ~> is_lub_const
   740   thelubI         ~> lub_eqI
   741   is_lub_lub      ~> is_lubD2
   742   lubI            ~> is_lub_lub
   743   unique_lub      ~> is_lub_unique
   744   is_ub_lub       ~> is_lub_rangeD1
   745   lub_bin_chain   ~> is_lub_bin_chain
   746   lub_fun         ~> is_lub_fun
   747   thelub_fun      ~> lub_fun
   748   thelub_cfun     ~> lub_cfun
   749   thelub_Pair     ~> lub_Pair
   750   lub_cprod       ~> is_lub_prod
   751   thelub_cprod    ~> lub_prod
   752   minimal_cprod   ~> minimal_prod
   753   inst_cprod_pcpo ~> inst_prod_pcpo
   754   UU_I            ~> bottomI
   755   compact_UU      ~> compact_bottom
   756   deflation_UU    ~> deflation_bottom
   757   finite_deflation_UU ~> finite_deflation_bottom
   758 
   759 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
   760 
   761   sq_ord_less_eq_trans ~> below_eq_trans
   762   sq_ord_eq_less_trans ~> eq_below_trans
   763   refl_less            ~> below_refl
   764   trans_less           ~> below_trans
   765   antisym_less         ~> below_antisym
   766   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
   767   box_less             ~> box_below
   768   rev_trans_less       ~> rev_below_trans
   769   not_less2not_eq      ~> not_below2not_eq
   770   less_UU_iff          ~> below_UU_iff
   771   flat_less_iff        ~> flat_below_iff
   772   adm_less             ~> adm_below
   773   adm_not_less         ~> adm_not_below
   774   adm_compact_not_less ~> adm_compact_not_below
   775   less_fun_def         ~> below_fun_def
   776   expand_fun_less      ~> fun_below_iff
   777   less_fun_ext         ~> fun_belowI
   778   less_discr_def       ~> below_discr_def
   779   discr_less_eq        ~> discr_below_eq
   780   less_unit_def        ~> below_unit_def
   781   less_cprod_def       ~> below_prod_def
   782   prod_lessI           ~> prod_belowI
   783   Pair_less_iff        ~> Pair_below_iff
   784   fst_less_iff         ~> fst_below_iff
   785   snd_less_iff         ~> snd_below_iff
   786   expand_cfun_less     ~> cfun_below_iff
   787   less_cfun_ext        ~> cfun_belowI
   788   injection_less       ~> injection_below
   789   less_up_def          ~> below_up_def
   790   not_Iup_less         ~> not_Iup_below
   791   Iup_less             ~> Iup_below
   792   up_less              ~> up_below
   793   Def_inject_less_eq   ~> Def_below_Def
   794   Def_less_is_eq       ~> Def_below_iff
   795   spair_less_iff       ~> spair_below_iff
   796   less_sprod           ~> below_sprod
   797   spair_less           ~> spair_below
   798   sfst_less_iff        ~> sfst_below_iff
   799   ssnd_less_iff        ~> ssnd_below_iff
   800   fix_least_less       ~> fix_least_below
   801   dist_less_one        ~> dist_below_one
   802   less_ONE             ~> below_ONE
   803   ONE_less_iff         ~> ONE_below_iff
   804   less_sinlD           ~> below_sinlD
   805   less_sinrD           ~> below_sinrD
   806 
   807 
   808 *** FOL and ZF ***
   809 
   810 * All constant names are now qualified internally and use proper
   811 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
   812 
   813 
   814 *** ML ***
   815 
   816 * Antiquotation @{assert} inlines a function bool -> unit that raises
   817 Fail if the argument is false.  Due to inlining the source position of
   818 failed assertions is included in the error output.
   819 
   820 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
   821 text is in practice always evaluated with a stable theory checkpoint.
   822 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
   823 
   824 * Antiquotation @{theory A} refers to theory A from the ancestry of
   825 the current context, not any accidental theory loader state as before.
   826 Potential INCOMPATIBILITY, subtle change in semantics.
   827 
   828 * Syntax.pretty_priority (default 0) configures the required priority
   829 of pretty-printed output and thus affects insertion of parentheses.
   830 
   831 * Syntax.default_root (default "any") configures the inner syntax
   832 category (nonterminal symbol) for parsing of terms.
   833 
   834 * Former exception Library.UnequalLengths now coincides with
   835 ListPair.UnequalLengths.
   836 
   837 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
   838 main functionality is provided by structure Simplifier.
   839 
   840 * Renamed raw "explode" function to "raw_explode" to emphasize its
   841 meaning.  Note that internally to Isabelle, Symbol.explode is used in
   842 almost all situations.
   843 
   844 * Discontinued obsolete function sys_error and exception SYS_ERROR.
   845 See implementation manual for further details on exceptions in
   846 Isabelle/ML.
   847 
   848 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
   849 meaning.
   850 
   851 * Renamed structure PureThy to Pure_Thy and moved most of its
   852 operations to structure Global_Theory, to emphasize that this is
   853 rarely-used global-only stuff.
   854 
   855 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
   856 instead (or tracing for high-volume output).
   857 
   858 * Configuration option show_question_marks only affects regular pretty
   859 printing of types and terms, not raw Term.string_of_vname.
   860 
   861 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
   862 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
   863 @{thms} for most purposes.
   864 
   865 * ML structure Unsynchronized is never opened, not even in Isar
   866 interaction mode as before.  Old Unsynchronized.set etc. have been
   867 discontinued -- use plain := instead.  This should be *rare* anyway,
   868 since modern tools always work via official context data, notably
   869 configuration options.
   870 
   871 * Parallel and asynchronous execution requires special care concerning
   872 interrupts.  Structure Exn provides some convenience functions that
   873 avoid working directly with raw Interrupt.  User code must not absorb
   874 interrupts -- intermediate handling (for cleanup etc.) needs to be
   875 followed by re-raising of the original exception.  Another common
   876 source of mistakes are "handle _" patterns, which make the meaning of
   877 the program subject to physical effects of the environment.
   878 
   879 
   880 
   881 New in Isabelle2009-2 (June 2010)
   882 ---------------------------------
   883 
   884 *** General ***
   885 
   886 * Authentic syntax for *all* logical entities (type classes, type
   887 constructors, term constants): provides simple and robust
   888 correspondence between formal entities and concrete syntax.  Within
   889 the parse tree / AST representations, "constants" are decorated by
   890 their category (class, type, const) and spelled out explicitly with
   891 their full internal name.
   892 
   893 Substantial INCOMPATIBILITY concerning low-level syntax declarations
   894 and translations (translation rules and translation functions in ML).
   895 Some hints on upgrading:
   896 
   897   - Many existing uses of 'syntax' and 'translations' can be replaced
   898     by more modern 'type_notation', 'notation' and 'abbreviation',
   899     which are independent of this issue.
   900 
   901   - 'translations' require markup within the AST; the term syntax
   902     provides the following special forms:
   903 
   904       CONST c   -- produces syntax version of constant c from context
   905       XCONST c  -- literally c, checked as constant from context
   906       c         -- literally c, if declared by 'syntax'
   907 
   908     Plain identifiers are treated as AST variables -- occasionally the
   909     system indicates accidental variables via the error "rhs contains
   910     extra variables".
   911 
   912     Type classes and type constructors are marked according to their
   913     concrete syntax.  Some old translations rules need to be written
   914     for the "type" category, using type constructor application
   915     instead of pseudo-term application of the default category
   916     "logic".
   917 
   918   - 'parse_translation' etc. in ML may use the following
   919     antiquotations:
   920 
   921       @{class_syntax c}   -- type class c within parse tree / AST
   922       @{term_syntax c}    -- type constructor c within parse tree / AST
   923       @{const_syntax c}   -- ML version of "CONST c" above
   924       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
   925 
   926   - Literal types within 'typed_print_translations', i.e. those *not*
   927     represented as pseudo-terms are represented verbatim.  Use @{class
   928     c} or @{type_name c} here instead of the above syntax
   929     antiquotations.
   930 
   931 Note that old non-authentic syntax was based on unqualified base
   932 names, so all of the above "constant" names would coincide.  Recall
   933 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
   934 diagnose syntax problems.
   935 
   936 * Type constructors admit general mixfix syntax, not just infix.
   937 
   938 * Concrete syntax may be attached to local entities without a proof
   939 body, too.  This works via regular mixfix annotations for 'fix',
   940 'def', 'obtain' etc. or via the explicit 'write' command, which is
   941 similar to the 'notation' command in theory specifications.
   942 
   943 * Discontinued unnamed infix syntax (legacy feature for many years) --
   944 need to specify constant name and syntax separately.  Internal ML
   945 datatype constructors have been renamed from InfixName to Infix etc.
   946 Minor INCOMPATIBILITY.
   947 
   948 * Schematic theorem statements need to be explicitly markup as such,
   949 via commands 'schematic_lemma', 'schematic_theorem',
   950 'schematic_corollary'.  Thus the relevance of the proof is made
   951 syntactically clear, which impacts performance in a parallel or
   952 asynchronous interactive environment.  Minor INCOMPATIBILITY.
   953 
   954 * Use of cumulative prems via "!" in some proof methods has been
   955 discontinued (old legacy feature).
   956 
   957 * References 'trace_simp' and 'debug_simp' have been replaced by
   958 configuration options stored in the context. Enabling tracing (the
   959 case of debugging is similar) in proofs works via
   960 
   961   using [[trace_simp = true]]
   962 
   963 Tracing is then active for all invocations of the simplifier in
   964 subsequent goal refinement steps. Tracing may also still be enabled or
   965 disabled via the ProofGeneral settings menu.
   966 
   967 * Separate commands 'hide_class', 'hide_type', 'hide_const',
   968 'hide_fact' replace the former 'hide' KIND command.  Minor
   969 INCOMPATIBILITY.
   970 
   971 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
   972 more efficient than combinations with -q1 or -q2.
   973 
   974 
   975 *** Pure ***
   976 
   977 * Proofterms record type-class reasoning explicitly, using the
   978 "unconstrain" operation internally.  This eliminates all sort
   979 constraints from a theorem and proof, introducing explicit
   980 OFCLASS-premises.  On the proof term level, this operation is
   981 automatically applied at theorem boundaries, such that closed proofs
   982 are always free of sort constraints.  INCOMPATIBILITY for tools that
   983 inspect proof terms.
   984 
   985 * Local theory specifications may depend on extra type variables that
   986 are not present in the result type -- arguments TYPE('a) :: 'a itself
   987 are added internally.  For example:
   988 
   989   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
   990 
   991 * Predicates of locales introduced by classes carry a mandatory
   992 "class" prefix.  INCOMPATIBILITY.
   993 
   994 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
   995 
   996 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
   997 'class' instead.
   998 
   999 * Command 'code_reflect' allows to incorporate generated ML code into
  1000 runtime environment; replaces immature code_datatype antiquotation.
  1001 INCOMPATIBILITY.
  1002 
  1003 * Code generator: simple concept for abstract datatypes obeying
  1004 invariants.
  1005 
  1006 * Code generator: details of internal data cache have no impact on the
  1007 user space functionality any longer.
  1008 
  1009 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  1010 subgoals.  This is more appropriate for interpretations with 'where'.
  1011 INCOMPATIBILITY.
  1012 
  1013 * Command 'example_proof' opens an empty proof body.  This allows to
  1014 experiment with Isar, without producing any persistent result.
  1015 
  1016 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  1017 within a local theory context, with explicit checking of the
  1018 constructors involved (in contrast to the raw 'syntax' versions).
  1019 
  1020 * Commands 'types' and 'typedecl' now work within a local theory
  1021 context -- without introducing dependencies on parameters or
  1022 assumptions, which is not possible in Isabelle/Pure.
  1023 
  1024 * Command 'defaultsort' has been renamed to 'default_sort', it works
  1025 within a local theory context.  Minor INCOMPATIBILITY.
  1026 
  1027 
  1028 *** HOL ***
  1029 
  1030 * Command 'typedef' now works within a local theory context -- without
  1031 introducing dependencies on parameters or assumptions, which is not
  1032 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  1033 contain multiple interpretations of local typedefs (with different
  1034 non-emptiness proofs), even in a global theory context.
  1035 
  1036 * New package for quotient types.  Commands 'quotient_type' and
  1037 'quotient_definition' may be used for defining types and constants by
  1038 quotient constructions.  An example is the type of integers created by
  1039 quotienting pairs of natural numbers:
  1040 
  1041   fun
  1042     intrel :: "(nat * nat) => (nat * nat) => bool"
  1043   where
  1044     "intrel (x, y) (u, v) = (x + v = u + y)"
  1045 
  1046   quotient_type int = "nat * nat" / intrel
  1047     by (auto simp add: equivp_def expand_fun_eq)
  1048 
  1049   quotient_definition
  1050     "0::int" is "(0::nat, 0::nat)"
  1051 
  1052 The method "lifting" can be used to lift of theorems from the
  1053 underlying "raw" type to the quotient type.  The example
  1054 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  1055 construction and provides a reasoning infrastructure for finite sets.
  1056 
  1057 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  1058 clash with new theory Quotient in Main HOL.
  1059 
  1060 * Moved the SMT binding into the main HOL session, eliminating
  1061 separate HOL-SMT session.
  1062 
  1063 * List membership infix mem operation is only an input abbreviation.
  1064 INCOMPATIBILITY.
  1065 
  1066 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  1067 for future developements; former Library/Word.thy is still present in
  1068 the AFP entry RSAPPS.
  1069 
  1070 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  1071 longer shadowed.  INCOMPATIBILITY.
  1072 
  1073 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  1074 INCOMPATIBILITY.
  1075 
  1076 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  1077 INCOMPATIBILITY.
  1078 
  1079 * Dropped normalizing_semiring etc; use the facts in semiring classes
  1080 instead.  INCOMPATIBILITY.
  1081 
  1082 * Dropped several real-specific versions of lemmas about floor and
  1083 ceiling; use the generic lemmas from theory "Archimedean_Field"
  1084 instead.  INCOMPATIBILITY.
  1085 
  1086   floor_number_of_eq         ~> floor_number_of
  1087   le_floor_eq_number_of      ~> number_of_le_floor
  1088   le_floor_eq_zero           ~> zero_le_floor
  1089   le_floor_eq_one            ~> one_le_floor
  1090   floor_less_eq_number_of    ~> floor_less_number_of
  1091   floor_less_eq_zero         ~> floor_less_zero
  1092   floor_less_eq_one          ~> floor_less_one
  1093   less_floor_eq_number_of    ~> number_of_less_floor
  1094   less_floor_eq_zero         ~> zero_less_floor
  1095   less_floor_eq_one          ~> one_less_floor
  1096   floor_le_eq_number_of      ~> floor_le_number_of
  1097   floor_le_eq_zero           ~> floor_le_zero
  1098   floor_le_eq_one            ~> floor_le_one
  1099   floor_subtract_number_of   ~> floor_diff_number_of
  1100   floor_subtract_one         ~> floor_diff_one
  1101   ceiling_number_of_eq       ~> ceiling_number_of
  1102   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  1103   ceiling_le_zero_eq         ~> ceiling_le_zero
  1104   ceiling_le_eq_one          ~> ceiling_le_one
  1105   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  1106   less_ceiling_eq_zero       ~> zero_less_ceiling
  1107   less_ceiling_eq_one        ~> one_less_ceiling
  1108   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  1109   ceiling_less_eq_zero       ~> ceiling_less_zero
  1110   ceiling_less_eq_one        ~> ceiling_less_one
  1111   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  1112   le_ceiling_eq_zero         ~> zero_le_ceiling
  1113   le_ceiling_eq_one          ~> one_le_ceiling
  1114   ceiling_subtract_number_of ~> ceiling_diff_number_of
  1115   ceiling_subtract_one       ~> ceiling_diff_one
  1116 
  1117 * Theory "Finite_Set": various folding_XXX locales facilitate the
  1118 application of the various fold combinators on finite sets.
  1119 
  1120 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  1121 provides abstract red-black tree type which is backed by "RBT_Impl" as
  1122 implementation.  INCOMPATIBILTY.
  1123 
  1124 * Theory Library/Coinductive_List has been removed -- superseded by
  1125 AFP/thys/Coinductive.
  1126 
  1127 * Theory PReal, including the type "preal" and related operations, has
  1128 been removed.  INCOMPATIBILITY.
  1129 
  1130 * Real: new development using Cauchy Sequences.
  1131 
  1132 * Split off theory "Big_Operators" containing setsum, setprod,
  1133 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  1134 
  1135 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  1136 "Int" etc.  INCOMPATIBILITY.
  1137 
  1138 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  1139 
  1140 * New set of rules "ac_simps" provides combined assoc / commute
  1141 rewrites for all interpretations of the appropriate generic locales.
  1142 
  1143 * Renamed theory "OrderedGroup" to "Groups" and split theory
  1144 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  1145 appropriate and more consistent names suitable for name prefixes
  1146 within the HOL theories.  INCOMPATIBILITY.
  1147 
  1148 * Some generic constants have been put to appropriate theories:
  1149   - less_eq, less: Orderings
  1150   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  1151   - inverse, divide: Rings
  1152 INCOMPATIBILITY.
  1153 
  1154 * More consistent naming of type classes involving orderings (and
  1155 lattices):
  1156 
  1157     lower_semilattice                   ~> semilattice_inf
  1158     upper_semilattice                   ~> semilattice_sup
  1159 
  1160     dense_linear_order                  ~> dense_linorder
  1161 
  1162     pordered_ab_group_add               ~> ordered_ab_group_add
  1163     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  1164     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  1165     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  1166     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  1167     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  1168     pordered_cancel_semiring            ~> ordered_cancel_semiring
  1169     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  1170     pordered_comm_ring                  ~> ordered_comm_ring
  1171     pordered_comm_semiring              ~> ordered_comm_semiring
  1172     pordered_ring                       ~> ordered_ring
  1173     pordered_ring_abs                   ~> ordered_ring_abs
  1174     pordered_semiring                   ~> ordered_semiring
  1175 
  1176     ordered_ab_group_add                ~> linordered_ab_group_add
  1177     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  1178     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  1179     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  1180     ordered_field                       ~> linordered_field
  1181     ordered_field_no_lb                 ~> linordered_field_no_lb
  1182     ordered_field_no_ub                 ~> linordered_field_no_ub
  1183     ordered_field_dense_linear_order    ~> dense_linordered_field
  1184     ordered_idom                        ~> linordered_idom
  1185     ordered_ring                        ~> linordered_ring
  1186     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  1187     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  1188     ordered_ring_strict                 ~> linordered_ring_strict
  1189     ordered_semidom                     ~> linordered_semidom
  1190     ordered_semiring                    ~> linordered_semiring
  1191     ordered_semiring_1                  ~> linordered_semiring_1
  1192     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  1193     ordered_semiring_strict             ~> linordered_semiring_strict
  1194 
  1195   The following slightly odd type classes have been moved to a
  1196   separate theory Library/Lattice_Algebras:
  1197 
  1198     lordered_ab_group_add               ~> lattice_ab_group_add
  1199     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  1200     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  1201     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  1202     lordered_ring                       ~> lattice_ring
  1203 
  1204 INCOMPATIBILITY.
  1205 
  1206 * Refined field classes:
  1207   - classes division_ring_inverse_zero, field_inverse_zero,
  1208     linordered_field_inverse_zero include rule inverse 0 = 0 --
  1209     subsumes former division_by_zero class;
  1210   - numerous lemmas have been ported from field to division_ring.
  1211 INCOMPATIBILITY.
  1212 
  1213 * Refined algebra theorem collections:
  1214   - dropped theorem group group_simps, use algebra_simps instead;
  1215   - dropped theorem group ring_simps, use field_simps instead;
  1216   - proper theorem collection field_simps subsumes former theorem
  1217     groups field_eq_simps and field_simps;
  1218   - dropped lemma eq_minus_self_iff which is a duplicate for
  1219     equal_neg_zero.
  1220 INCOMPATIBILITY.
  1221 
  1222 * Theory Finite_Set and List: some lemmas have been generalized from
  1223 sets to lattices:
  1224 
  1225   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  1226   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  1227   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  1228   union_Union_fold_union        ~> sup_Sup_fold_sup
  1229   Inter_fold_inter              ~> Inf_fold_inf
  1230   Union_fold_union              ~> Sup_fold_sup
  1231   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  1232   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  1233   INTER_fold_inter              ~> INFI_fold_inf
  1234   UNION_fold_union              ~> SUPR_fold_sup
  1235 
  1236 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  1237 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  1238 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  1239 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  1240 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  1241 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  1242 
  1243 * Reorganized theory Multiset: swapped notation of pointwise and
  1244 multiset order:
  1245 
  1246   - pointwise ordering is instance of class order with standard syntax
  1247     <= and <;
  1248   - multiset ordering has syntax <=# and <#; partial order properties
  1249     are provided by means of interpretation with prefix
  1250     multiset_order;
  1251   - less duplication, less historical organization of sections,
  1252     conversion from associations lists to multisets, rudimentary code
  1253     generation;
  1254   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  1255     if needed.
  1256 
  1257 Renamed:
  1258 
  1259   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  1260   multi_count_ext  ~>  multiset_ext
  1261   diff_union_inverse2  ~>  diff_union_cancelR
  1262 
  1263 INCOMPATIBILITY.
  1264 
  1265 * Theory Permutation: replaced local "remove" by List.remove1.
  1266 
  1267 * Code generation: ML and OCaml code is decorated with signatures.
  1268 
  1269 * Theory List: added transpose.
  1270 
  1271 * Library/Nat_Bijection.thy is a collection of bijective functions
  1272 between nat and other types, which supersedes the older libraries
  1273 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  1274 
  1275   Constants:
  1276   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  1277   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  1278   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  1279   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  1280   Countable.pair_encode           ~> prod_encode
  1281   NatIso.prod2nat                 ~> prod_encode
  1282   NatIso.nat2prod                 ~> prod_decode
  1283   NatIso.sum2nat                  ~> sum_encode
  1284   NatIso.nat2sum                  ~> sum_decode
  1285   NatIso.list2nat                 ~> list_encode
  1286   NatIso.nat2list                 ~> list_decode
  1287   NatIso.set2nat                  ~> set_encode
  1288   NatIso.nat2set                  ~> set_decode
  1289 
  1290   Lemmas:
  1291   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  1292   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  1293   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  1294   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  1295   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  1296   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  1297   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  1298   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  1299   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  1300   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  1301   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  1302   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  1303   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  1304 
  1305 * Sledgehammer:
  1306   - Renamed ATP commands:
  1307     atp_info     ~> sledgehammer running_atps
  1308     atp_kill     ~> sledgehammer kill_atps
  1309     atp_messages ~> sledgehammer messages
  1310     atp_minimize ~> sledgehammer minimize
  1311     print_atps   ~> sledgehammer available_atps
  1312     INCOMPATIBILITY.
  1313   - Added user's manual ("isabelle doc sledgehammer").
  1314   - Added option syntax and "sledgehammer_params" to customize
  1315     Sledgehammer's behavior.  See the manual for details.
  1316   - Modified the Isar proof reconstruction code so that it produces
  1317     direct proofs rather than proofs by contradiction.  (This feature
  1318     is still experimental.)
  1319   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  1320     full-typed mode.
  1321   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  1322 
  1323 * Nitpick:
  1324   - Added and implemented "binary_ints" and "bits" options.
  1325   - Added "std" option and implemented support for nonstandard models.
  1326   - Added and implemented "finitize" option to improve the precision
  1327     of infinite datatypes based on a monotonicity analysis.
  1328   - Added support for quotient types.
  1329   - Added support for "specification" and "ax_specification"
  1330     constructs.
  1331   - Added support for local definitions (for "function" and
  1332     "termination" proofs).
  1333   - Added support for term postprocessors.
  1334   - Optimized "Multiset.multiset" and "FinFun.finfun".
  1335   - Improved efficiency of "destroy_constrs" optimization.
  1336   - Fixed soundness bugs related to "destroy_constrs" optimization and
  1337     record getters.
  1338   - Fixed soundness bug related to higher-order constructors.
  1339   - Fixed soundness bug when "full_descrs" is enabled.
  1340   - Improved precision of set constructs.
  1341   - Added "atoms" option.
  1342   - Added cache to speed up repeated Kodkod invocations on the same
  1343     problems.
  1344   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  1345     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  1346     "SAT4J_Light".  INCOMPATIBILITY.
  1347   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  1348     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  1349   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  1350 
  1351 * Method "induct" now takes instantiations of the form t, where t is not
  1352   a variable, as a shorthand for "x == t", where x is a fresh variable.
  1353   If this is not intended, t has to be enclosed in parentheses.
  1354   By default, the equalities generated by definitional instantiations
  1355   are pre-simplified, which may cause parameters of inductive cases
  1356   to disappear, or may even delete some of the inductive cases.
  1357   Use "induct (no_simp)" instead of "induct" to restore the old
  1358   behaviour. The (no_simp) option is also understood by the "cases"
  1359   and "nominal_induct" methods, which now perform pre-simplification, too.
  1360   INCOMPATIBILITY.
  1361 
  1362 
  1363 *** HOLCF ***
  1364 
  1365 * Variable names in lemmas generated by the domain package have
  1366 changed; the naming scheme is now consistent with the HOL datatype
  1367 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  1368 
  1369 * The domain package no longer defines the function "foo_copy" for
  1370 recursive domain "foo".  The reach lemma is now stated directly in
  1371 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  1372 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  1373 
  1374 * Most definedness lemmas generated by the domain package (previously
  1375 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  1376 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  1377 Proofs that used definedness lemmas as intro rules may break,
  1378 potential INCOMPATIBILITY.
  1379 
  1380 * Induction and casedist rules generated by the domain package now
  1381 declare proper case_names (one called "bottom", and one named for each
  1382 constructor).  INCOMPATIBILITY.
  1383 
  1384 * For mutually-recursive domains, separate "reach" and "take_lemma"
  1385 rules are generated for each domain, INCOMPATIBILITY.
  1386 
  1387   foo_bar.reach       ~> foo.reach  bar.reach
  1388   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  1389 
  1390 * Some lemmas generated by the domain package have been renamed for
  1391 consistency with the datatype package, INCOMPATIBILITY.
  1392 
  1393   foo.ind        ~> foo.induct
  1394   foo.finite_ind ~> foo.finite_induct
  1395   foo.coind      ~> foo.coinduct
  1396   foo.casedist   ~> foo.exhaust
  1397   foo.exhaust    ~> foo.nchotomy
  1398 
  1399 * For consistency with other definition packages, the fixrec package
  1400 now generates qualified theorem names, INCOMPATIBILITY.
  1401 
  1402   foo_simps  ~> foo.simps
  1403   foo_unfold ~> foo.unfold
  1404   foo_induct ~> foo.induct
  1405 
  1406 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  1407 method and internal fixrec proofs now use the default simpset instead.
  1408 INCOMPATIBILITY.
  1409 
  1410 * The "contlub" predicate has been removed.  Proof scripts should use
  1411 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  1412 
  1413 * The "admw" predicate has been removed, INCOMPATIBILITY.
  1414 
  1415 * The constants cpair, cfst, and csnd have been removed in favor of
  1416 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  1417 
  1418 
  1419 *** ML ***
  1420 
  1421 * Antiquotations for basic formal entities:
  1422 
  1423     @{class NAME}         -- type class
  1424     @{class_syntax NAME}  -- syntax representation of the above
  1425 
  1426     @{type_name NAME}     -- logical type
  1427     @{type_abbrev NAME}   -- type abbreviation
  1428     @{nonterminal NAME}   -- type of concrete syntactic category
  1429     @{type_syntax NAME}   -- syntax representation of any of the above
  1430 
  1431     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  1432     @{const_abbrev NAME}  -- abbreviated constant
  1433     @{const_syntax NAME}  -- syntax representation of any of the above
  1434 
  1435 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  1436 syntax constant (cf. 'syntax' command).
  1437 
  1438 * Antiquotation @{make_string} inlines a function to print arbitrary
  1439 values similar to the ML toplevel.  The result is compiler dependent
  1440 and may fall back on "?" in certain situations.
  1441 
  1442 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  1443 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  1444 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  1445 not work with the asynchronous Isar document model.
  1446 
  1447 * Configuration options now admit dynamic default values, depending on
  1448 the context or even global references.
  1449 
  1450 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  1451 uses an efficient external library if available (for Poly/ML).
  1452 
  1453 * Renamed some important ML structures, while keeping the old names
  1454 for some time as aliases within the structure Legacy:
  1455 
  1456   OuterKeyword  ~>  Keyword
  1457   OuterLex      ~>  Token
  1458   OuterParse    ~>  Parse
  1459   OuterSyntax   ~>  Outer_Syntax
  1460   PrintMode     ~>  Print_Mode
  1461   SpecParse     ~>  Parse_Spec
  1462   ThyInfo       ~>  Thy_Info
  1463   ThyLoad       ~>  Thy_Load
  1464   ThyOutput     ~>  Thy_Output
  1465   TypeInfer     ~>  Type_Infer
  1466 
  1467 Note that "open Legacy" simplifies porting of sources, but forgetting
  1468 to remove it again will complicate porting again in the future.
  1469 
  1470 * Most operations that refer to a global context are named
  1471 accordingly, e.g. Simplifier.global_context or
  1472 ProofContext.init_global.  There are some situations where a global
  1473 context actually works, but under normal circumstances one needs to
  1474 pass the proper local context through the code!
  1475 
  1476 * Discontinued old TheoryDataFun with its copy/init operation -- data
  1477 needs to be pure.  Functor Theory_Data_PP retains the traditional
  1478 Pretty.pp argument to merge, which is absent in the standard
  1479 Theory_Data version.
  1480 
  1481 * Sorts.certify_sort and derived "cert" operations for types and terms
  1482 no longer minimize sorts.  Thus certification at the boundary of the
  1483 inference kernel becomes invariant under addition of class relations,
  1484 which is an important monotonicity principle.  Sorts are now minimized
  1485 in the syntax layer only, at the boundary between the end-user and the
  1486 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  1487 explicitly in rare situations.
  1488 
  1489 * Renamed old-style Drule.standard to Drule.export_without_context, to
  1490 emphasize that this is in no way a standard operation.
  1491 INCOMPATIBILITY.
  1492 
  1493 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  1494 usual for resolution.  Rare INCOMPATIBILITY.
  1495 
  1496 * Renamed varify/unvarify operations to varify_global/unvarify_global
  1497 to emphasize that these only work in a global situation (which is
  1498 quite rare).
  1499 
  1500 * Curried take and drop in library.ML; negative length is interpreted
  1501 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  1502 
  1503 * Proof terms: type substitutions on proof constants now use canonical
  1504 order of type variables.  INCOMPATIBILITY for tools working with proof
  1505 terms.
  1506 
  1507 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  1508 may no longer carry premises.  User-level specifications are
  1509 transformed accordingly by Thm.add_axiom/add_def.
  1510 
  1511 
  1512 *** System ***
  1513 
  1514 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  1515 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  1516 proof terms are enabled unconditionally in the new HOL-Proofs image.
  1517 
  1518 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  1519 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  1520 respectively.
  1521 
  1522 * Old lib/scripts/polyml-platform is superseded by the
  1523 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  1524 variant, even on a 64 bit machine.  The following example setting
  1525 prefers 64 bit if available:
  1526 
  1527   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  1528 
  1529 * The preliminary Isabelle/jEdit application demonstrates the emerging
  1530 Isabelle/Scala layer for advanced prover interaction and integration.
  1531 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  1532 component.
  1533 
  1534 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  1535 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  1536 similar to the default assignment of the document preparation system
  1537 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  1538 provides some operations for direct access to the font without asking
  1539 the user for manual installation.
  1540 
  1541 
  1542 
  1543 New in Isabelle2009-1 (December 2009)
  1544 -------------------------------------
  1545 
  1546 *** General ***
  1547 
  1548 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  1549 one backslash should be used, even in ML sources.
  1550 
  1551 
  1552 *** Pure ***
  1553 
  1554 * Locale interpretation propagates mixins along the locale hierarchy.
  1555 The currently only available mixins are the equations used to map
  1556 local definitions to terms of the target domain of an interpretation.
  1557 
  1558 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  1559 loc" to print all interpretations of locale "loc" in the theory.
  1560 Interpretations in proofs are not shown.
  1561 
  1562 * Thoroughly revised locales tutorial.  New section on conditional
  1563 interpretation.
  1564 
  1565 * On instantiation of classes, remaining undefined class parameters
  1566 are formally declared.  INCOMPATIBILITY.
  1567 
  1568 
  1569 *** Document preparation ***
  1570 
  1571 * New generalized style concept for printing terms: @{foo (style) ...}
  1572 instead of @{foo_style style ...}  (old form is still retained for
  1573 backward compatibility).  Styles can be also applied for
  1574 antiquotations prop, term_type and typeof.
  1575 
  1576 
  1577 *** HOL ***
  1578 
  1579 * New proof method "smt" for a combination of first-order logic with
  1580 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  1581 fixed-size bitvectors; there is also basic support for higher-order
  1582 features (esp. lambda abstractions).  It is an incomplete decision
  1583 procedure based on external SMT solvers using the oracle mechanism;
  1584 for the SMT solver Z3, this method is proof-producing.  Certificates
  1585 are provided to avoid calling the external solvers solely for
  1586 re-checking proofs.  Due to a remote SMT service there is no need for
  1587 installing SMT solvers locally.  See src/HOL/SMT.
  1588 
  1589 * New commands to load and prove verification conditions generated by
  1590 the Boogie program verifier or derived systems (e.g. the Verifying C
  1591 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1592 
  1593 * New counterexample generator tool 'nitpick' based on the Kodkod
  1594 relational model finder.  See src/HOL/Tools/Nitpick and
  1595 src/HOL/Nitpick_Examples.
  1596 
  1597 * New commands 'code_pred' and 'values' to invoke the predicate
  1598 compiler and to enumerate values of inductive predicates.
  1599 
  1600 * A tabled implementation of the reflexive transitive closure.
  1601 
  1602 * New implementation of quickcheck uses generic code generator;
  1603 default generators are provided for all suitable HOL types, records
  1604 and datatypes.  Old quickcheck can be re-activated importing theory
  1605 Library/SML_Quickcheck.
  1606 
  1607 * New testing tool Mirabelle for automated proof tools.  Applies
  1608 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1609 every proof step in a theory.  To be used in batch mode via the
  1610 "mirabelle" utility.
  1611 
  1612 * New proof method "sos" (sum of squares) for nonlinear real
  1613 arithmetic (originally due to John Harison). It requires theory
  1614 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1615 works well in practice on quantifier-free real arithmetic with +, -,
  1616 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1617 inequalities between polynomials.  It makes use of external
  1618 semidefinite programming solvers.  Method "sos" generates a
  1619 certificate that can be pasted into the proof thus avoiding the need
  1620 to call an external tool every time the proof is checked.  See
  1621 src/HOL/Library/Sum_Of_Squares.
  1622 
  1623 * New method "linarith" invokes existing linear arithmetic decision
  1624 procedure only.
  1625 
  1626 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1627 
  1628 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1629 Causes full type information to be output to the ATPs.  This slows
  1630 ATPs down considerably but eliminates a source of unsound "proofs"
  1631 that fail later.
  1632 
  1633 * New method "metisFT": A version of metis that uses full type
  1634 information in order to avoid failures of proof reconstruction.
  1635 
  1636 * New evaluator "approximate" approximates an real valued term using
  1637 the same method as the approximation method.
  1638 
  1639 * Method "approximate" now supports arithmetic expressions as
  1640 boundaries of intervals and implements interval splitting and Taylor
  1641 series expansion.
  1642 
  1643 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1644 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1645 
  1646 * New theory SupInf of the supremum and infimum operators for sets of
  1647 reals.
  1648 
  1649 * New theory Probability, which contains a development of measure
  1650 theory, eventually leading to Lebesgue integration and probability.
  1651 
  1652 * Extended Multivariate Analysis to include derivation and Brouwer's
  1653 fixpoint theorem.
  1654 
  1655 * Reorganization of number theory, INCOMPATIBILITY:
  1656   - new number theory development for nat and int, in theories Divides
  1657     and GCD as well as in new session Number_Theory
  1658   - some constants and facts now suffixed with _nat and _int
  1659     accordingly
  1660   - former session NumberTheory now named Old_Number_Theory, including
  1661     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1662   - moved theory Pocklington from src/HOL/Library to
  1663     src/HOL/Old_Number_Theory
  1664 
  1665 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1666 lcm of finite and infinite sets. It is shown that they form a complete
  1667 lattice.
  1668 
  1669 * Class semiring_div requires superclass no_zero_divisors and proof of
  1670 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1671 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1672 generalized to class semiring_div, subsuming former theorems
  1673 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1674 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1675 INCOMPATIBILITY.
  1676 
  1677 * Refinements to lattice classes and sets:
  1678   - less default intro/elim rules in locale variant, more default
  1679     intro/elim rules in class variant: more uniformity
  1680   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1681     le_inf_iff
  1682   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1683     sup_aci)
  1684   - renamed ACI to inf_sup_aci
  1685   - new class "boolean_algebra"
  1686   - class "complete_lattice" moved to separate theory
  1687     "Complete_Lattice"; corresponding constants (and abbreviations)
  1688     renamed and with authentic syntax:
  1689     Set.Inf ~>    Complete_Lattice.Inf
  1690     Set.Sup ~>    Complete_Lattice.Sup
  1691     Set.INFI ~>   Complete_Lattice.INFI
  1692     Set.SUPR ~>   Complete_Lattice.SUPR
  1693     Set.Inter ~>  Complete_Lattice.Inter
  1694     Set.Union ~>  Complete_Lattice.Union
  1695     Set.INTER ~>  Complete_Lattice.INTER
  1696     Set.UNION ~>  Complete_Lattice.UNION
  1697   - authentic syntax for
  1698     Set.Pow
  1699     Set.image
  1700   - mere abbreviations:
  1701     Set.empty               (for bot)
  1702     Set.UNIV                (for top)
  1703     Set.inter               (for inf, formerly Set.Int)
  1704     Set.union               (for sup, formerly Set.Un)
  1705     Complete_Lattice.Inter  (for Inf)
  1706     Complete_Lattice.Union  (for Sup)
  1707     Complete_Lattice.INTER  (for INFI)
  1708     Complete_Lattice.UNION  (for SUPR)
  1709   - object-logic definitions as far as appropriate
  1710 
  1711 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1712 Un_subset_iff are explicitly deleted as default simp rules; then also
  1713 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1714 deleted to achieve the desired effect.
  1715 
  1716 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1717 rules by default any longer; the same applies to min_max.inf_absorb1
  1718 etc.  INCOMPATIBILITY.
  1719 
  1720 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1721 pred_set_conv by default.  INCOMPATIBILITY.
  1722 
  1723 * Power operations on relations and functions are now one dedicated
  1724 constant "compow" with infix syntax "^^".  Power operation on
  1725 multiplicative monoids retains syntax "^" and is now defined generic
  1726 in class power.  INCOMPATIBILITY.
  1727 
  1728 * Relation composition "R O S" now has a more standard argument order:
  1729 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1730 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1731 break, since the O_assoc rule was not rewritten like this.  Fix using
  1732 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1733 
  1734 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1735 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1736 INCOMPATIBILITY.
  1737 
  1738 * Most rules produced by inductive and datatype package have mandatory
  1739 prefixes.  INCOMPATIBILITY.
  1740 
  1741 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1742 the attribute of the same name.  Each of the theorems in the list
  1743 DERIV_intros assumes composition with an additional function and
  1744 matches a variable to the derivative, which has to be solved by the
  1745 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1746 of most elementary terms.  Former Maclauren.DERIV_tac and
  1747 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1748 INCOMPATIBILITY.
  1749 
  1750 * Code generator attributes follow the usual underscore convention:
  1751     code_unfold     replaces    code unfold
  1752     code_post       replaces    code post
  1753     etc.
  1754   INCOMPATIBILITY.
  1755 
  1756 * Renamed methods:
  1757     sizechange -> size_change
  1758     induct_scheme -> induction_schema
  1759   INCOMPATIBILITY.
  1760 
  1761 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1762 INCOMPATIBILITY, use "undefined" directly.
  1763 
  1764 * Renamed theorems:
  1765     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1766     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1767     Suc_plus1 -> Suc_eq_plus1
  1768     *anti_sym -> *antisym*
  1769     vector_less_eq_def -> vector_le_def
  1770   INCOMPATIBILITY.
  1771 
  1772 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1773 INCOMPATIBILITY.
  1774 
  1775 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1776 INCOMPATIBILITY.
  1777 
  1778 
  1779 *** HOLCF ***
  1780 
  1781 * Theory Representable defines a class "rep" of domains that are
  1782 representable (via an ep-pair) in the universal domain type "udom".
  1783 Instances are provided for all type constructors defined in HOLCF.
  1784 
  1785 * The 'new_domain' command is a purely definitional version of the
  1786 domain package, for representable domains.  Syntax is identical to the
  1787 old domain package.  The 'new_domain' package also supports indirect
  1788 recursion using previously-defined type constructors.  See
  1789 src/HOLCF/ex/New_Domain.thy for examples.
  1790 
  1791 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1792 on the left-hand side of an equation, and then performs
  1793 simplification.  Rewriting is done using rules declared with the
  1794 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1795 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1796 
  1797 * The pattern-match compiler in 'fixrec' can now handle constructors
  1798 with HOL function types.  Pattern-match combinators for the Pair
  1799 constructor are pre-configured.
  1800 
  1801 * The 'fixrec' package now produces better fixed-point induction rules
  1802 for mutually-recursive definitions:  Induction rules have conclusions
  1803 of the form "P foo bar" instead of "P <foo, bar>".
  1804 
  1805 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1806 been renamed to "below".  The name "below" now replaces "less" in many
  1807 theorem names.  (Legacy theorem names using "less" are still supported
  1808 as well.)
  1809 
  1810 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1811 patterns can be used to generate strictness rules, or to make
  1812 functions more strict (much like the bang-patterns supported by the
  1813 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1814 examples.
  1815 
  1816 
  1817 *** ML ***
  1818 
  1819 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1820 errors and run-time exceptions, including detailed source positions.
  1821 
  1822 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1823 identified entries, with some additional information such as source
  1824 position, logical grouping etc.
  1825 
  1826 * Theory and context data is now introduced by the simplified and
  1827 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1828 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1829 copy operation) is still available for some time.
  1830 
  1831 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1832 provides a high-level programming interface to synchronized state
  1833 variables with atomic update.  This works via pure function
  1834 application within a critical section -- its runtime should be as
  1835 short as possible; beware of deadlocks if critical code is nested,
  1836 either directly or indirectly via other synchronized variables!
  1837 
  1838 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1839 wraps raw ML references, explicitly indicating their non-thread-safe
  1840 behaviour.  The Isar toplevel keeps this structure open, to
  1841 accommodate Proof General as well as quick and dirty interactive
  1842 experiments with references.
  1843 
  1844 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1845 parallel tactical reasoning.
  1846 
  1847 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1848 are similar to SUBPROOF, but are slightly more flexible: only the
  1849 specified parts of the subgoal are imported into the context, and the
  1850 body tactic may introduce new subgoals and schematic variables.
  1851 
  1852 * Old tactical METAHYPS, which does not observe the proof context, has
  1853 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1854 or Subgoal.FOCUS etc.
  1855 
  1856 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  1857 functors have their own ML name space there is no point to mark them
  1858 separately.)  Minor INCOMPATIBILITY.
  1859 
  1860 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  1861 
  1862 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  1863 INCOMPATIBILITY.
  1864 
  1865 * Operations of structure Skip_Proof no longer require quick_and_dirty
  1866 mode, which avoids critical setmp.
  1867 
  1868 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  1869 combinators for "args".  INCOMPATIBILITY, need to use simplified
  1870 Attrib/Method.setup introduced in Isabelle2009.
  1871 
  1872 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  1873 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  1874 last resort.  INCOMPATIBILITY.
  1875 
  1876 * Display.pretty_thm now requires a proper context (cf. former
  1877 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  1878 or even Display.pretty_thm_without_context as last resort.
  1879 INCOMPATIBILITY.
  1880 
  1881 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  1882 Syntax.pretty_typ/term directly, preferably with proper context
  1883 instead of global theory.
  1884 
  1885 
  1886 *** System ***
  1887 
  1888 * Further fine tuning of parallel proof checking, scales up to 8 cores
  1889 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  1890 usedir option -q.
  1891 
  1892 * Support for additional "Isabelle components" via etc/components, see
  1893 also the system manual.
  1894 
  1895 * The isabelle makeall tool now operates on all components with
  1896 IsaMakefile, not just hardwired "logics".
  1897 
  1898 * Removed "compress" option from isabelle-process and isabelle usedir;
  1899 this is always enabled.
  1900 
  1901 * Discontinued support for Poly/ML 4.x versions.
  1902 
  1903 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  1904 on a given logic image.  This requires the lighttpd webserver and is
  1905 currently supported on Linux only.
  1906 
  1907 
  1908 
  1909 New in Isabelle2009 (April 2009)
  1910 --------------------------------
  1911 
  1912 *** General ***
  1913 
  1914 * Simplified main Isabelle executables, with less surprises on
  1915 case-insensitive file-systems (such as Mac OS).
  1916 
  1917   - The main Isabelle tool wrapper is now called "isabelle" instead of
  1918     "isatool."
  1919 
  1920   - The former "isabelle" alias for "isabelle-process" has been
  1921     removed (should rarely occur to regular users).
  1922 
  1923   - The former "isabelle-interface" and its alias "Isabelle" have been
  1924     removed (interfaces are now regular Isabelle tools).
  1925 
  1926 Within scripts and make files, the Isabelle environment variables
  1927 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  1928 respectively.  (The latter are still available as legacy feature.)
  1929 
  1930 The old isabelle-interface wrapper could react in confusing ways if
  1931 the interface was uninstalled or changed otherwise.  Individual
  1932 interface tool configuration is now more explicit, see also the
  1933 Isabelle system manual.  In particular, Proof General is now available
  1934 via "isabelle emacs".
  1935 
  1936 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  1937 purge installed copies of Isabelle executables and re-run "isabelle
  1938 install -p ...", or use symlinks.
  1939 
  1940 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  1941 old ~/isabelle, which was slightly non-standard and apt to cause
  1942 surprises on case-insensitive file-systems (such as Mac OS).
  1943 
  1944 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  1945 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  1946 care is required when using older releases of Isabelle.  Note that
  1947 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  1948 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  1949 
  1950 * Proofs of fully specified statements are run in parallel on
  1951 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  1952 a regular 4-core machine, if the initial heap space is made reasonably
  1953 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  1954 
  1955 * The main reference manuals ("isar-ref", "implementation", and
  1956 "system") have been updated and extended.  Formally checked references
  1957 as hyperlinks are now available uniformly.
  1958 
  1959 
  1960 *** Pure ***
  1961 
  1962 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  1963 respects.  The most important changes are listed below.  See the
  1964 Tutorial on Locales ("locales" manual) for details.
  1965 
  1966 - In locale expressions, instantiation replaces renaming.  Parameters
  1967 must be declared in a for clause.  To aid compatibility with previous
  1968 parameter inheritance, in locale declarations, parameters that are not
  1969 'touched' (instantiation position "_" or omitted) are implicitly added
  1970 with their syntax at the beginning of the for clause.
  1971 
  1972 - Syntax from abbreviations and definitions in locales is available in
  1973 locale expressions and context elements.  The latter is particularly
  1974 useful in locale declarations.
  1975 
  1976 - More flexible mechanisms to qualify names generated by locale
  1977 expressions.  Qualifiers (prefixes) may be specified in locale
  1978 expressions, and can be marked as mandatory (syntax: "name!:") or
  1979 optional (syntax "name?:").  The default depends for plain "name:"
  1980 depends on the situation where a locale expression is used: in
  1981 commands 'locale' and 'sublocale' prefixes are optional, in
  1982 'interpretation' and 'interpret' prefixes are mandatory.  The old
  1983 implicit qualifiers derived from the parameter names of a locale are
  1984 no longer generated.
  1985 
  1986 - Command "sublocale l < e" replaces "interpretation l < e".  The
  1987 instantiation clause in "interpretation" and "interpret" (square
  1988 brackets) is no longer available.  Use locale expressions.
  1989 
  1990 - When converting proof scripts, mandatory qualifiers in
  1991 'interpretation' and 'interpret' should be retained by default, even
  1992 if this is an INCOMPATIBILITY compared to former behavior.  In the
  1993 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  1994 in locale expressions range over a single locale instance only.
  1995 
  1996 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  1997 In existing theorem specifications replace the includes element by the
  1998 respective context elements of the included locale, omitting those
  1999 that are already present in the theorem specification.  Multiple
  2000 assume elements of a locale should be replaced by a single one
  2001 involving the locale predicate.  In the proof body, declarations (most
  2002 notably theorems) may be regained by interpreting the respective
  2003 locales in the proof context as required (command "interpret").
  2004 
  2005 If using "includes" in replacement of a target solely because the
  2006 parameter types in the theorem are not as general as in the target,
  2007 consider declaring a new locale with additional type constraints on
  2008 the parameters (context element "constrains").
  2009 
  2010 - Discontinued "locale (open)".  INCOMPATIBILITY.
  2011 
  2012 - Locale interpretation commands no longer attempt to simplify goal.
  2013 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  2014 methods intro_locales and unfold_locales to clarify.
  2015 
  2016 - Locale interpretation commands no longer accept interpretation
  2017 attributes.  INCOMPATIBILITY.
  2018 
  2019 * Class declaration: so-called "base sort" must not be given in import
  2020 list any longer, but is inferred from the specification.  Particularly
  2021 in HOL, write
  2022 
  2023     class foo = ...
  2024 
  2025 instead of
  2026 
  2027     class foo = type + ...
  2028 
  2029 * Class target: global versions of theorems stemming do not carry a
  2030 parameter prefix any longer.  INCOMPATIBILITY.
  2031 
  2032 * Class 'instance' command no longer accepts attached definitions.
  2033 INCOMPATIBILITY, use proper 'instantiation' target instead.
  2034 
  2035 * Recovered hiding of consts, which was accidentally broken in
  2036 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  2037 makes c inaccessible; consider using ``hide (open) const c'' instead.
  2038 
  2039 * Slightly more coherent Pure syntax, with updated documentation in
  2040 isar-ref manual.  Removed locales meta_term_syntax and
  2041 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  2042 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  2043 directly in regular applications.
  2044 
  2045 * There is a new syntactic category "float_const" for signed decimal
  2046 fractions (e.g. 123.45 or -123.45).
  2047 
  2048 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  2049 interface with 'setup' command instead.
  2050 
  2051 * Command 'local_setup' is similar to 'setup', but operates on a local
  2052 theory context.
  2053 
  2054 * The 'axiomatization' command now only works within a global theory
  2055 context.  INCOMPATIBILITY.
  2056 
  2057 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  2058 hypotheses.  Sorts required in the course of reasoning need to be
  2059 covered by the constraints in the initial statement, completed by the
  2060 type instance information of the background theory.  Non-trivial sort
  2061 hypotheses, which rarely occur in practice, may be specified via
  2062 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  2063 
  2064   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  2065 
  2066 The result contains an implicit sort hypotheses as before --
  2067 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  2068 normalization.
  2069 
  2070 * Generalized Isar history, with support for linear undo, direct state
  2071 addressing etc.
  2072 
  2073 * Changed defaults for unify configuration options:
  2074 
  2075   unify_trace_bound = 50 (formerly 25)
  2076   unify_search_bound = 60 (formerly 30)
  2077 
  2078 * Different bookkeeping for code equations (INCOMPATIBILITY):
  2079 
  2080   a) On theory merge, the last set of code equations for a particular
  2081      constant is taken (in accordance with the policy applied by other
  2082      parts of the code generator framework).
  2083 
  2084   b) Code equations stemming from explicit declarations (e.g. code
  2085      attribute) gain priority over default code equations stemming
  2086      from definition, primrec, fun etc.
  2087 
  2088 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  2089 
  2090 * Unified theorem tables for both code generators.  Thus [code
  2091 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  2092 
  2093 * Command 'find_consts' searches for constants based on type and name
  2094 patterns, e.g.
  2095 
  2096     find_consts "_ => bool"
  2097 
  2098 By default, matching is against subtypes, but it may be restricted to
  2099 the whole type.  Searching by name is possible.  Multiple queries are
  2100 conjunctive and queries may be negated by prefixing them with a
  2101 hyphen:
  2102 
  2103     find_consts strict: "_ => bool" name: "Int" -"int => int"
  2104 
  2105 * New 'find_theorems' criterion "solves" matches theorems that
  2106 directly solve the current goal (modulo higher-order unification).
  2107 
  2108 * Auto solve feature for main theorem statements: whenever a new goal
  2109 is stated, "find_theorems solves" is called; any theorems that could
  2110 solve the lemma directly are listed as part of the goal state.
  2111 Cf. associated options in Proof General Isabelle settings menu,
  2112 enabled by default, with reasonable timeout for pathological cases of
  2113 higher-order unification.
  2114 
  2115 
  2116 *** Document preparation ***
  2117 
  2118 * Antiquotation @{lemma} now imitates a regular terminal proof,
  2119 demanding keyword 'by' and supporting the full method expression
  2120 syntax just like the Isar command 'by'.
  2121 
  2122 
  2123 *** HOL ***
  2124 
  2125 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  2126 points Main and Complex_Main remain as before.
  2127 
  2128 * Logic image HOL-Plain provides a minimal HOL with the most important
  2129 tools available (inductive, datatype, primrec, ...).  This facilitates
  2130 experimentation and tool development.  Note that user applications
  2131 (and library theories) should never refer to anything below theory
  2132 Main, as before.
  2133 
  2134 * Logic image HOL-Main stops at theory Main, and thus facilitates
  2135 experimentation due to shorter build times.
  2136 
  2137 * Logic image HOL-NSA contains theories of nonstandard analysis which
  2138 were previously part of former HOL-Complex.  Entry point Hyperreal
  2139 remains valid, but theories formerly using Complex_Main should now use
  2140 new entry point Hypercomplex.
  2141 
  2142 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  2143 Posix processes.  Avoids potentially expensive forking of the ML
  2144 process.  New thread-based implementation also works on non-Unix
  2145 platforms (Cygwin).  Provers are no longer hardwired, but defined
  2146 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  2147 commands are covered in the isar-ref manual.
  2148 
  2149 * Wrapper scripts for remote SystemOnTPTP service allows to use
  2150 sledgehammer without local ATP installation (Vampire etc.). Other
  2151 provers may be included via suitable ML wrappers, see also
  2152 src/HOL/ATP_Linkup.thy.
  2153 
  2154 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  2155 menu.
  2156 
  2157 * The metis method no longer fails because the theorem is too trivial
  2158 (contains the empty clause).
  2159 
  2160 * The metis method now fails in the usual manner, rather than raising
  2161 an exception, if it determines that it cannot prove the theorem.
  2162 
  2163 * Method "coherent" implements a prover for coherent logic (see also
  2164 src/Tools/coherent.ML).
  2165 
  2166 * Constants "undefined" and "default" replace "arbitrary".  Usually
  2167 "undefined" is the right choice to replace "arbitrary", though
  2168 logically there is no difference.  INCOMPATIBILITY.
  2169 
  2170 * Command "value" now integrates different evaluation mechanisms.  The
  2171 result of the first successful evaluation mechanism is printed.  In
  2172 square brackets a particular named evaluation mechanisms may be
  2173 specified (currently, [SML], [code] or [nbe]).  See further
  2174 src/HOL/ex/Eval_Examples.thy.
  2175 
  2176 * Normalization by evaluation now allows non-leftlinear equations.
  2177 Declare with attribute [code nbe].
  2178 
  2179 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  2180 as the structured Isar versions "cases" and "induct", cf. the
  2181 corresponding "cases" and "induct" attributes.  Mutual induction rules
  2182 are now presented as a list of individual projections
  2183 (e.g. foo_bar.inducts for types foo and bar); the old format with
  2184 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  2185 rare situations a different rule is selected --- notably nested tuple
  2186 elimination instead of former prod.exhaust: use explicit (case_tac t
  2187 rule: prod.exhaust) here.
  2188 
  2189 * Attributes "cases", "induct", "coinduct" support "del" option.
  2190 
  2191 * Removed fact "case_split_thm", which duplicates "case_split".
  2192 
  2193 * The option datatype has been moved to a new theory Option.  Renamed
  2194 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  2195 
  2196 * New predicate "strict_mono" classifies strict functions on partial
  2197 orders.  With strict functions on linear orders, reasoning about
  2198 (in)equalities is facilitated by theorems "strict_mono_eq",
  2199 "strict_mono_less_eq" and "strict_mono_less".
  2200 
  2201 * Some set operations are now proper qualified constants with
  2202 authentic syntax.  INCOMPATIBILITY:
  2203 
  2204     op Int ~>   Set.Int
  2205     op Un ~>    Set.Un
  2206     INTER ~>    Set.INTER
  2207     UNION ~>    Set.UNION
  2208     Inter ~>    Set.Inter
  2209     Union ~>    Set.Union
  2210     {} ~>       Set.empty
  2211     UNIV ~>     Set.UNIV
  2212 
  2213 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  2214 theory Set.
  2215 
  2216 * Auxiliary class "itself" has disappeared -- classes without any
  2217 parameter are treated as expected by the 'class' command.
  2218 
  2219 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  2220 
  2221 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  2222 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  2223 
  2224 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  2225 method "approximation".  It proves formulas on real values by using
  2226 interval arithmetic.  In the formulas are also the transcendental
  2227 functions sin, cos, tan, atan, ln, exp and the constant pi are
  2228 allowed. For examples see
  2229 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  2230 
  2231 * Theory "Reflection" now resides in HOL/Library.
  2232 
  2233 * Entry point to Word library now simply named "Word".
  2234 INCOMPATIBILITY.
  2235 
  2236 * Made source layout more coherent with logical distribution
  2237 structure:
  2238 
  2239     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  2240     src/HOL/Library/Code_Message.thy ~> src/HOL/
  2241     src/HOL/Library/GCD.thy ~> src/HOL/
  2242     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  2243     src/HOL/Library/Parity.thy ~> src/HOL/
  2244     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  2245     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  2246     src/HOL/Real/Lubs.thy ~> src/HOL/
  2247     src/HOL/Real/PReal.thy ~> src/HOL/
  2248     src/HOL/Real/Rational.thy ~> src/HOL/
  2249     src/HOL/Real/RComplete.thy ~> src/HOL/
  2250     src/HOL/Real/RealDef.thy ~> src/HOL/
  2251     src/HOL/Real/RealPow.thy ~> src/HOL/
  2252     src/HOL/Real/Real.thy ~> src/HOL/
  2253     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  2254     src/HOL/Complex/Complex.thy ~> src/HOL/
  2255     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  2256     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  2257     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  2258     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  2259     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  2260     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  2261     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  2262     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  2263     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  2264     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  2265     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  2266     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  2267     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  2268     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  2269     src/HOL/Real/Float ~> src/HOL/Library/
  2270     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  2271     src/HOL/Real/RealVector.thy ~> src/HOL/
  2272 
  2273     src/HOL/arith_data.ML ~> src/HOL/Tools
  2274     src/HOL/hologic.ML ~> src/HOL/Tools
  2275     src/HOL/simpdata.ML ~> src/HOL/Tools
  2276     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  2277     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  2278     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  2279     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  2280     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  2281     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  2282     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  2283 
  2284     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  2285     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  2286     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  2287     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  2288     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  2289     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  2290 
  2291 * If methods "eval" and "evaluation" encounter a structured proof
  2292 state with !!/==>, only the conclusion is evaluated to True (if
  2293 possible), avoiding strange error messages.
  2294 
  2295 * Method "sizechange" automates termination proofs using (a
  2296 modification of) the size-change principle.  Requires SAT solver.  See
  2297 src/HOL/ex/Termination.thy for examples.
  2298 
  2299 * Simplifier: simproc for let expressions now unfolds if bound
  2300 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  2301 
  2302 * Method "arith": Linear arithmetic now ignores all inequalities when
  2303 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  2304 
  2305 * New attribute "arith" for facts that should always be used
  2306 automatically by arithmetic. It is intended to be used locally in
  2307 proofs, e.g.
  2308 
  2309   assumes [arith]: "x > 0"
  2310 
  2311 Global usage is discouraged because of possible performance impact.
  2312 
  2313 * New classes "top" and "bot" with corresponding operations "top" and
  2314 "bot" in theory Orderings; instantiation of class "complete_lattice"
  2315 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  2316 
  2317 * Changed definition lemma "less_fun_def" in order to provide an
  2318 instance for preorders on functions; use lemma "less_le" instead.
  2319 INCOMPATIBILITY.
  2320 
  2321 * Theory Orderings: class "wellorder" moved here, with explicit
  2322 induction rule "less_induct" as assumption.  For instantiation of
  2323 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  2324 INCOMPATIBILITY.
  2325 
  2326 * Theory Orderings: added class "preorder" as superclass of "order".
  2327 INCOMPATIBILITY: Instantiation proofs for order, linorder
  2328 etc. slightly changed.  Some theorems named order_class.* now named
  2329 preorder_class.*.
  2330 
  2331 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  2332 "diag" to "Id_on".
  2333 
  2334 * Theory Finite_Set: added a new fold combinator of type
  2335 
  2336   ('a => 'b => 'b) => 'b => 'a set => 'b
  2337 
  2338 Occasionally this is more convenient than the old fold combinator
  2339 which is now defined in terms of the new one and renamed to
  2340 fold_image.
  2341 
  2342 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  2343 and "ring_simps" have been replaced by "algebra_simps" (which can be
  2344 extended with further lemmas!).  At the moment both still exist but
  2345 the former will disappear at some point.
  2346 
  2347 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  2348 class recpower.  Type-specific simp rules for various recpower types
  2349 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  2350 
  2351 rat_power_0    -> power_0
  2352 rat_power_Suc  -> power_Suc
  2353 realpow_0      -> power_0
  2354 realpow_Suc    -> power_Suc
  2355 complexpow_0   -> power_0
  2356 complexpow_Suc -> power_Suc
  2357 power_poly_0   -> power_0
  2358 power_poly_Suc -> power_Suc
  2359 
  2360 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  2361 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  2362 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  2363 of lemmas from Divides has been generalized from nat to class
  2364 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  2365 renames resulting from duplicate elimination:
  2366 
  2367     dvd_def_mod ~>          dvd_eq_mod_eq_0
  2368     zero_dvd_iff ~>         dvd_0_left_iff
  2369     dvd_0 ~>                dvd_0_right
  2370     DIVISION_BY_ZERO_DIV ~> div_by_0
  2371     DIVISION_BY_ZERO_MOD ~> mod_by_0
  2372     mult_div ~>             div_mult_self2_is_id
  2373     mult_mod ~>             mod_mult_self2_is_0
  2374 
  2375 * Theory IntDiv: removed many lemmas that are instances of class-based
  2376 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  2377 rename old lemmas as follows:
  2378 
  2379 dvd_diff               -> nat_dvd_diff
  2380 dvd_zminus_iff         -> dvd_minus_iff
  2381 mod_add1_eq            -> mod_add_eq
  2382 mod_mult1_eq           -> mod_mult_right_eq
  2383 mod_mult1_eq'          -> mod_mult_left_eq
  2384 mod_mult_distrib_mod   -> mod_mult_eq
  2385 nat_mod_add_left_eq    -> mod_add_left_eq
  2386 nat_mod_add_right_eq   -> mod_add_right_eq
  2387 nat_mod_div_trivial    -> mod_div_trivial
  2388 nat_mod_mod_trivial    -> mod_mod_trivial
  2389 zdiv_zadd_self1        -> div_add_self1
  2390 zdiv_zadd_self2        -> div_add_self2
  2391 zdiv_zmult_self1       -> div_mult_self2_is_id
  2392 zdiv_zmult_self2       -> div_mult_self1_is_id
  2393 zdvd_triv_left         -> dvd_triv_left
  2394 zdvd_triv_right        -> dvd_triv_right
  2395 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  2396 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  2397 zmod_zadd_left_eq      -> mod_add_left_eq
  2398 zmod_zadd_right_eq     -> mod_add_right_eq
  2399 zmod_zadd_self1        -> mod_add_self1
  2400 zmod_zadd_self2        -> mod_add_self2
  2401 zmod_zadd1_eq          -> mod_add_eq
  2402 zmod_zdiff1_eq         -> mod_diff_eq
  2403 zmod_zdvd_zmod         -> mod_mod_cancel
  2404 zmod_zmod_cancel       -> mod_mod_cancel
  2405 zmod_zmult_self1       -> mod_mult_self2_is_0
  2406 zmod_zmult_self2       -> mod_mult_self1_is_0
  2407 zmod_1                 -> mod_by_1
  2408 zdiv_1                 -> div_by_1
  2409 zdvd_abs1              -> abs_dvd_iff
  2410 zdvd_abs2              -> dvd_abs_iff
  2411 zdvd_refl              -> dvd_refl
  2412 zdvd_trans             -> dvd_trans
  2413 zdvd_zadd              -> dvd_add
  2414 zdvd_zdiff             -> dvd_diff
  2415 zdvd_zminus_iff        -> dvd_minus_iff
  2416 zdvd_zminus2_iff       -> minus_dvd_iff
  2417 zdvd_zmultD            -> dvd_mult_right
  2418 zdvd_zmultD2           -> dvd_mult_left
  2419 zdvd_zmult_mono        -> mult_dvd_mono
  2420 zdvd_0_right           -> dvd_0_right
  2421 zdvd_0_left            -> dvd_0_left_iff
  2422 zdvd_1_left            -> one_dvd
  2423 zminus_dvd_iff         -> minus_dvd_iff
  2424 
  2425 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  2426 
  2427 * The real numbers offer decimal input syntax: 12.34 is translated
  2428 into 1234/10^2. This translation is not reversed upon output.
  2429 
  2430 * Theory Library/Polynomial defines an abstract type 'a poly of
  2431 univariate polynomials with coefficients of type 'a.  In addition to
  2432 the standard ring operations, it also supports div and mod.  Code
  2433 generation is also supported, using list-style constructors.
  2434 
  2435 * Theory Library/Inner_Product defines a class of real_inner for real
  2436 inner product spaces, with an overloaded operation inner :: 'a => 'a
  2437 => real.  Class real_inner is a subclass of real_normed_vector from
  2438 theory RealVector.
  2439 
  2440 * Theory Library/Product_Vector provides instances for the product
  2441 type 'a * 'b of several classes from RealVector and Inner_Product.
  2442 Definitions of addition, subtraction, scalar multiplication, norms,
  2443 and inner products are included.
  2444 
  2445 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  2446 addition to the field operations, numerals and case syntax are also
  2447 supported.
  2448 
  2449 * Theory Library/Diagonalize provides constructive version of Cantor's
  2450 first diagonalization argument.
  2451 
  2452 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  2453 zlcm (for int); carried together from various gcd/lcm developements in
  2454 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  2455 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  2456 may recover tupled syntax as follows:
  2457 
  2458     hide (open) const gcd
  2459     abbreviation gcd where
  2460       "gcd == (%(a, b). GCD.gcd a b)"
  2461     notation (output)
  2462       GCD.gcd ("gcd '(_, _')")
  2463 
  2464 The same works for lcm, zgcd, zlcm.
  2465 
  2466 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  2467 instantiations for algebraic structures.  Removed some duplicate
  2468 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  2469 
  2470 * ML antiquotation @{code} takes a constant as argument and generates
  2471 corresponding code in background and inserts name of the corresponding
  2472 resulting ML value/function/datatype constructor binding in place.
  2473 All occurrences of @{code} with a single ML block are generated
  2474 simultaneously.  Provides a generic and safe interface for
  2475 instrumentalizing code generation.  See
  2476 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  2477 In future you ought to refrain from ad-hoc compiling generated SML
  2478 code on the ML toplevel.  Note that (for technical reasons) @{code}
  2479 cannot refer to constants for which user-defined serializations are
  2480 set.  Refer to the corresponding ML counterpart directly in that
  2481 cases.
  2482 
  2483 * Command 'rep_datatype': instead of theorem names the command now
  2484 takes a list of terms denoting the constructors of the type to be
  2485 represented as datatype.  The characteristic theorems have to be
  2486 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  2487 have disappeared in favour of existing ones:
  2488 
  2489     unit_induct                 ~> unit.induct
  2490     prod_induct                 ~> prod.induct
  2491     sum_induct                  ~> sum.induct
  2492     Suc_Suc_eq                  ~> nat.inject
  2493     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  2494 
  2495 
  2496 *** HOL-Algebra ***
  2497 
  2498 * New locales for orders and lattices where the equivalence relation
  2499 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  2500 locales use a record structure with field eq for the equivalence.
  2501 
  2502 * New theory of factorial domains.
  2503 
  2504 * Units_l_inv and Units_r_inv are now simp rules by default.
  2505 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  2506 and/or r_inv will now also require deletion of these lemmas.
  2507 
  2508 * Renamed the following theorems, INCOMPATIBILITY:
  2509 
  2510 UpperD ~> Upper_memD
  2511 LowerD ~> Lower_memD
  2512 least_carrier ~> least_closed
  2513 greatest_carrier ~> greatest_closed
  2514 greatest_Lower_above ~> greatest_Lower_below
  2515 one_zero ~> carrier_one_zero
  2516 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  2517 
  2518 
  2519 *** HOL-Nominal ***
  2520 
  2521 * Nominal datatypes can now contain type-variables.
  2522 
  2523 * Commands 'nominal_inductive' and 'equivariance' work with local
  2524 theory targets.
  2525 
  2526 * Nominal primrec can now works with local theory targets and its
  2527 specification syntax now conforms to the general format as seen in
  2528 'inductive' etc.
  2529 
  2530 * Method "perm_simp" honours the standard simplifier attributes
  2531 (no_asm), (no_asm_use) etc.
  2532 
  2533 * The new predicate #* is defined like freshness, except that on the
  2534 left hand side can be a set or list of atoms.
  2535 
  2536 * Experimental command 'nominal_inductive2' derives strong induction
  2537 principles for inductive definitions.  In contrast to
  2538 'nominal_inductive', which can only deal with a fixed number of
  2539 binders, it can deal with arbitrary expressions standing for sets of
  2540 atoms to be avoided.  The only inductive definition we have at the
  2541 moment that needs this generalisation is the typing rule for Lets in
  2542 the algorithm W:
  2543 
  2544  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  2545  -----------------------------------------------------------------
  2546          Gamma |- Let x be t1 in t2 : T2
  2547 
  2548 In this rule one wants to avoid all the binders that are introduced by
  2549 "close Gamma T1".  We are looking for other examples where this
  2550 feature might be useful.  Please let us know.
  2551 
  2552 
  2553 *** HOLCF ***
  2554 
  2555 * Reimplemented the simplification procedure for proving continuity
  2556 subgoals.  The new simproc is extensible; users can declare additional
  2557 continuity introduction rules with the attribute [cont2cont].
  2558 
  2559 * The continuity simproc now uses a different introduction rule for
  2560 solving continuity subgoals on terms with lambda abstractions.  In
  2561 some rare cases the new simproc may fail to solve subgoals that the
  2562 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  2563 Potential INCOMPATIBILITY.
  2564 
  2565 * Command 'fixrec': specification syntax now conforms to the general
  2566 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  2567 examples.  INCOMPATIBILITY.
  2568 
  2569 
  2570 *** ZF ***
  2571 
  2572 * Proof of Zorn's Lemma for partial orders.
  2573 
  2574 
  2575 *** ML ***
  2576 
  2577 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  2578 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  2579 depends on multithreading, so timouts will not work before Poly/ML
  2580 5.2.1!
  2581 
  2582 * High-level support for concurrent ML programming, see
  2583 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  2584 particularly convenient to organize independent functional
  2585 computations.  The concept of "synchronized variables" provides a
  2586 higher-order interface for components with shared state, avoiding the
  2587 delicate details of mutexes and condition variables.  (Requires
  2588 Poly/ML 5.2.1 or later.)
  2589 
  2590 * ML bindings produced via Isar commands are stored within the Isar
  2591 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2592 become thread-safe and work with undo as expected (concerning
  2593 top-level bindings, not side-effects on global references).
  2594 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2595 compiler at runtime; really global bindings need to be given outside a
  2596 theory.  (Requires Poly/ML 5.2 or later.)
  2597 
  2598 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2599 context.  Top-level ML bindings are stored within the proof context in
  2600 a purely sequential fashion, disregarding the nested proof structure.
  2601 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2602 proof.  (Requires Poly/ML 5.2 or later.)
  2603 
  2604 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2605 and Method.setup, as well as Isar commands 'attribute_setup' and
  2606 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2607 existing code accordingly, or use plain 'setup' together with old
  2608 Method.add_method.
  2609 
  2610 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2611 to 'a -> thm, while results are always tagged with an authentic oracle
  2612 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2613 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2614 accordingly.  Note that extra performance may be gained by producing
  2615 the cterm carefully, avoiding slow Thm.cterm_of.
  2616 
  2617 * Simplified interface for defining document antiquotations via
  2618 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2619 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2620 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2621 examples.
  2622 
  2623 * More systematic treatment of long names, abstract name bindings, and
  2624 name space operations.  Basic operations on qualified names have been
  2625 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2626 Long_Name.append.  Old type bstring has been mostly replaced by
  2627 abstract type binding (see structure Binding), which supports precise
  2628 qualification by packages and local theory targets, as well as proper
  2629 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2630 bstring values into Binding.name, or better pass through abstract
  2631 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2632 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2633 
  2634 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2635 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2636 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2637 
  2638 * Disposed old type and term read functions (Sign.read_def_typ,
  2639 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2640 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2641 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2642 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2643 resort for legacy applications.
  2644 
  2645 * Disposed old declarations, tactics, tactic combinators that refer to
  2646 the simpset or claset of an implicit theory (such as Addsimps,
  2647 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2648 embedded ML text, or local_simpset_of with a proper context passed as
  2649 explicit runtime argument.
  2650 
  2651 * Rules and tactics that read instantiations (read_instantiate,
  2652 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2653 context, which is required for parsing and type-checking.  Moreover,
  2654 the variables are specified as plain indexnames, not string encodings
  2655 thereof.  INCOMPATIBILITY.
  2656 
  2657 * Generic Toplevel.add_hook interface allows to analyze the result of
  2658 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2659 for theorem dependency output of transactions resulting in a new
  2660 theory state.
  2661 
  2662 * ML antiquotations: block-structured compilation context indicated by
  2663 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2664 
  2665   @{binding name}                         - basic name binding
  2666   @{let ?pat = term}                      - term abbreviation (HO matching)
  2667   @{note name = fact}                     - fact abbreviation
  2668   @{thm fact}                             - singleton fact (with attributes)
  2669   @{thms fact}                            - general fact (with attributes)
  2670   @{lemma prop by method}                 - singleton goal
  2671   @{lemma prop by meth1 meth2}            - singleton goal
  2672   @{lemma prop1 ... propN by method}      - general goal
  2673   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2674   @{lemma (open) ...}                     - open derivation
  2675 
  2676 
  2677 *** System ***
  2678 
  2679 * The Isabelle "emacs" tool provides a specific interface to invoke
  2680 Proof General / Emacs, with more explicit failure if that is not
  2681 installed (the old isabelle-interface script silently falls back on
  2682 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2683 installation location of the Proof General distribution.
  2684 
  2685 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2686 the Isabelle process into a JVM/Scala application.  See
  2687 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2688 process wrapper has been discontinued.)
  2689 
  2690 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2691 
  2692 * Various status messages (with exact source position information) are
  2693 emitted, if proper markup print mode is enabled.  This allows
  2694 user-interface components to provide detailed feedback on internal
  2695 prover operations.
  2696 
  2697 
  2698 
  2699 New in Isabelle2008 (June 2008)
  2700 -------------------------------
  2701 
  2702 *** General ***
  2703 
  2704 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2705 and updated, with formally checked references as hyperlinks.
  2706 
  2707 * Theory loader: use_thy (and similar operations) no longer set the
  2708 implicit ML context, which was occasionally hard to predict and in
  2709 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2710 provides a proper context already.
  2711 
  2712 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2713 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2714 'use' within a theory file will do the job.
  2715 
  2716 * Name space merge now observes canonical order, i.e. the second space
  2717 is inserted into the first one, while existing entries in the first
  2718 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2719 swap theory imports.
  2720 
  2721 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2722 INCOMPATIBILITY in identifier syntax etc.
  2723 
  2724 * Outer syntax: string tokens no longer admit escaped white space,
  2725 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2726 white space without escapes.
  2727 
  2728 * Outer syntax: string tokens may contain arbitrary character codes
  2729 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2730 "foo_bar".
  2731 
  2732 
  2733 *** Pure ***
  2734 
  2735 * Context-dependent token translations.  Default setup reverts locally
  2736 fixed variables, and adds hilite markup for undeclared frees.
  2737 
  2738 * Unused theorems can be found using the new command 'unused_thms'.
  2739 There are three ways of invoking it:
  2740 
  2741 (1) unused_thms
  2742      Only finds unused theorems in the current theory.
  2743 
  2744 (2) unused_thms thy_1 ... thy_n -
  2745      Finds unused theorems in the current theory and all of its ancestors,
  2746      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2747 
  2748 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2749      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2750      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2751      their ancestors.
  2752 
  2753 In order to increase the readability of the list produced by
  2754 unused_thms, theorems that have been created by a particular instance
  2755 of a theory command such as 'inductive' or 'function' are considered
  2756 to belong to the same "group", meaning that if at least one theorem in
  2757 this group is used, the other theorems in the same group are no longer
  2758 reported as unused.  Moreover, if all theorems in the group are
  2759 unused, only one theorem in the group is displayed.
  2760 
  2761 Note that proof objects have to be switched on in order for
  2762 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2763 usually the case when using Proof General with the default settings).
  2764 
  2765 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2766 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2767 duplicate fact bindings, or even accidental fact duplications.  Note
  2768 that tools may maintain dynamically scoped facts systematically, using
  2769 PureThy.add_thms_dynamic.
  2770 
  2771 * Command 'hide' now allows to hide from "fact" name space as well.
  2772 
  2773 * Eliminated destructive theorem database, simpset, claset, and
  2774 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2775 update of theories within ML code.
  2776 
  2777 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2778 INCOMPATIBILITY, object-logics depending on former Pure require
  2779 additional setup PureThy.old_appl_syntax_setup; object-logics
  2780 depending on former CPure need to refer to Pure.
  2781 
  2782 * Commands 'use' and 'ML' are now purely functional, operating on
  2783 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2784 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2785 INCOMPATIBILITY.
  2786 
  2787 * Command 'setup': discontinued implicit version with ML reference.
  2788 
  2789 * Instantiation target allows for simultaneous specification of class
  2790 instance operations together with an instantiation proof.
  2791 Type-checking phase allows to refer to class operations uniformly.
  2792 See src/HOL/Complex/Complex.thy for an Isar example and
  2793 src/HOL/Library/Eval.thy for an ML example.
  2794 
  2795 * Indexing of literal facts: be more serious about including only
  2796 facts from the visible specification/proof context, but not the
  2797 background context (locale etc.).  Affects `prop` notation and method
  2798 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2799 situations.
  2800 
  2801 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2802 "(open)" option, which used to expose internal bound variables to the
  2803 proof text.
  2804 
  2805 * Isar statements: removed obsolete case "rule_context".
  2806 INCOMPATIBILITY, better use explicit fixes/assumes.
  2807 
  2808 * Locale proofs: default proof step now includes 'unfold_locales';
  2809 hence 'proof' without argument may be used to unfold locale
  2810 predicates.
  2811 
  2812 
  2813 *** Document preparation ***
  2814 
  2815 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2816 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2817 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2818 spot); renamed link color from "darkblue" to "linkcolor" (default
  2819 value unchanged, can be redefined via \definecolor); no longer sets
  2820 "a4paper" option (unnecessary or even intrusive).
  2821 
  2822 * Antiquotation @{lemma A method} proves proposition A by the given
  2823 method (either a method name or a method name plus (optional) method
  2824 arguments in parentheses) and prints A just like @{prop A}.
  2825 
  2826 
  2827 *** HOL ***
  2828 
  2829 * New primrec package.  Specification syntax conforms in style to
  2830 definition/function/....  No separate induction rule is provided.  The
  2831 "primrec" command distinguishes old-style and new-style specifications
  2832 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2833 When adjusting theories, beware: constants stemming from new-style
  2834 primrec specifications have authentic syntax.
  2835 
  2836 * Metis prover is now an order of magnitude faster, and also works
  2837 with multithreading.
  2838 
  2839 * Metis: the maximum number of clauses that can be produced from a
  2840 theorem is now given by the attribute max_clauses.  Theorems that
  2841 exceed this number are ignored, with a warning printed.
  2842 
  2843 * Sledgehammer no longer produces structured proofs by default. To
  2844 enable, declare [[sledgehammer_full = true]].  Attributes
  2845 reconstruction_modulus, reconstruction_sorts renamed
  2846 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2847 
  2848 * Method "induct_scheme" derives user-specified induction rules
  2849 from well-founded induction and completeness of patterns. This factors
  2850 out some operations that are done internally by the function package
  2851 and makes them available separately.  See
  2852 src/HOL/ex/Induction_Scheme.thy for examples.
  2853 
  2854 * More flexible generation of measure functions for termination
  2855 proofs: Measure functions can be declared by proving a rule of the
  2856 form "is_measure f" and giving it the [measure_function] attribute.
  2857 The "is_measure" predicate is logically meaningless (always true), and
  2858 just guides the heuristic.  To find suitable measure functions, the
  2859 termination prover sets up the goal "is_measure ?f" of the appropriate
  2860 type and generates all solutions by prolog-style backwards proof using
  2861 the declared rules.
  2862 
  2863 This setup also deals with rules like 
  2864 
  2865   "is_measure f ==> is_measure (list_size f)"
  2866 
  2867 which accommodates nested datatypes that recurse through lists.
  2868 Similar rules are predeclared for products and option types.
  2869 
  2870 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  2871 
  2872   INCOMPATIBILITIES:
  2873 
  2874   - Definitions of overloaded constants on sets have to be replaced by
  2875     definitions on => and bool.
  2876 
  2877   - Some definitions of overloaded operators on sets can now be proved
  2878     using the definitions of the operators on => and bool.  Therefore,
  2879     the following theorems have been renamed:
  2880 
  2881       subset_def   -> subset_eq
  2882       psubset_def  -> psubset_eq
  2883       set_diff_def -> set_diff_eq
  2884       Compl_def    -> Compl_eq
  2885       Sup_set_def  -> Sup_set_eq
  2886       Inf_set_def  -> Inf_set_eq
  2887       sup_set_def  -> sup_set_eq
  2888       inf_set_def  -> inf_set_eq
  2889 
  2890   - Due to the incompleteness of the HO unification algorithm, some
  2891     rules such as subst may require manual instantiation, if some of
  2892     the unknowns in the rule is a set.
  2893 
  2894   - Higher order unification and forward proofs:
  2895     The proof pattern
  2896 
  2897       have "P (S::'a set)" <...>
  2898       then have "EX S. P S" ..
  2899 
  2900     no longer works (due to the incompleteness of the HO unification
  2901     algorithm) and must be replaced by the pattern
  2902 
  2903       have "EX S. P S"
  2904       proof
  2905         show "P S" <...>
  2906       qed
  2907 
  2908   - Calculational reasoning with subst (or similar rules):
  2909     The proof pattern
  2910 
  2911       have "P (S::'a set)" <...>
  2912       also have "S = T" <...>
  2913       finally have "P T" .
  2914 
  2915     no longer works (for similar reasons as the previous example) and
  2916     must be replaced by something like
  2917 
  2918       have "P (S::'a set)" <...>
  2919       moreover have "S = T" <...>
  2920       ultimately have "P T" by simp
  2921 
  2922   - Tactics or packages written in ML code:
  2923     Code performing pattern matching on types via
  2924 
  2925       Type ("set", [T]) => ...
  2926 
  2927     must be rewritten. Moreover, functions like strip_type or
  2928     binder_types no longer return the right value when applied to a
  2929     type of the form
  2930 
  2931       T1 => ... => Tn => U => bool
  2932 
  2933     rather than
  2934 
  2935       T1 => ... => Tn => U set
  2936 
  2937 * Merged theories Wellfounded_Recursion, Accessible_Part and
  2938 Wellfounded_Relations to theory Wellfounded.
  2939 
  2940 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  2941 
  2942 * Class finite no longer treats UNIV as class parameter.  Use class
  2943 enum from theory Library/Enum instead to achieve a similar effect.
  2944 INCOMPATIBILITY.
  2945 
  2946 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  2947 and "Cons".  INCOMPATIBILITY.
  2948 
  2949 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  2950 Potential INCOMPATIBILITY.
  2951 
  2952 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  2953 injective_fst_snd removed, use split_eta and prod_eqI instead.
  2954 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  2955 
  2956 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  2957 the same name in theory Orderings:
  2958 
  2959   less_trans
  2960   less_linear
  2961   le_imp_less_or_eq
  2962   le_less_trans
  2963   less_le_trans
  2964   less_not_sym
  2965   less_asym
  2966 
  2967 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  2968 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  2969 and different variable names.
  2970 
  2971 * Library/Option_ord.thy: Canonical order on option type.
  2972 
  2973 * Library/RBT.thy: Red-black trees, an efficient implementation of
  2974 finite maps.
  2975 
  2976 * Library/Countable.thy: Type class for countable types.
  2977 
  2978 * Theory Int: The representation of numerals has changed.  The infix
  2979 operator BIT and the bit datatype with constructors B0 and B1 have
  2980 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  2981 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  2982 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  2983 accordingly.
  2984 
  2985 * Theory Nat: definition of <= and < on natural numbers no longer
  2986 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  2987 le_def and less_def have disappeared.  Consider lemmas not_less
  2988 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  2989 
  2990 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  2991 (whose purpose mainly is for various fold_set functionals) have been
  2992 abandoned in favor of the existing algebraic classes
  2993 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  2994 lower_semilattice (resp. upper_semilattice) and linorder.
  2995 INCOMPATIBILITY.
  2996 
  2997 * Theory Transitive_Closure: induct and cases rules now declare proper
  2998 case_names ("base" and "step").  INCOMPATIBILITY.
  2999 
  3000 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  3001 lattices.  The form set-specific version is available as
  3002 Inductive.lfp_ordinal_induct_set.
  3003 
  3004 * Renamed theorems "power.simps" to "power_int.simps".
  3005 INCOMPATIBILITY.
  3006 
  3007 * Class semiring_div provides basic abstract properties of semirings
  3008 with division and modulo operations.  Subsumes former class dvd_mod.
  3009 
  3010 * Merged theories IntDef, Numeral and IntArith into unified theory
  3011 Int.  INCOMPATIBILITY.
  3012 
  3013 * Theory Library/Code_Index: type "index" now represents natural
  3014 numbers rather than integers.  INCOMPATIBILITY.
  3015 
  3016 * New class "uminus" with operation "uminus" (split of from class
  3017 "minus" which now only has operation "minus", binary).
  3018 INCOMPATIBILITY.
  3019 
  3020 * Constants "card", "internal_split", "option_map" now with authentic
  3021 syntax.  INCOMPATIBILITY.
  3022 
  3023 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  3024 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  3025 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  3026 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  3027 Sup_set_def, le_def, less_def, option_map_def now with object
  3028 equality.  INCOMPATIBILITY.
  3029 
  3030 * Records. Removed K_record, and replaced it by pure lambda term
  3031 %x. c. The simplifier setup is now more robust against eta expansion.
  3032 INCOMPATIBILITY: in cases explicitly referring to K_record.
  3033 
  3034 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  3035 
  3036 * Library/ListVector: new theory of arithmetic vector operations.
  3037 
  3038 * Library/Order_Relation: new theory of various orderings as sets of
  3039 pairs.  Defines preorders, partial orders, linear orders and
  3040 well-orders on sets and on types.
  3041 
  3042 
  3043 *** ZF ***
  3044 
  3045 * Renamed some theories to allow to loading both ZF and HOL in the
  3046 same session:
  3047 
  3048   Datatype  -> Datatype_ZF
  3049   Inductive -> Inductive_ZF
  3050   Int       -> Int_ZF
  3051   IntDiv    -> IntDiv_ZF
  3052   Nat       -> Nat_ZF
  3053   List      -> List_ZF
  3054   Main      -> Main_ZF
  3055 
  3056 INCOMPATIBILITY: ZF theories that import individual theories below
  3057 Main might need to be adapted.  Regular theory Main is still
  3058 available, as trivial extension of Main_ZF.
  3059 
  3060 
  3061 *** ML ***
  3062 
  3063 * ML within Isar: antiquotation @{const name} or @{const
  3064 name(typargs)} produces statically-checked Const term.
  3065 
  3066 * Functor NamedThmsFun: data is available to the user as dynamic fact
  3067 (of the same name).  Removed obsolete print command.
  3068 
  3069 * Removed obsolete "use_legacy_bindings" function.
  3070 
  3071 * The ``print mode'' is now a thread-local value derived from a global
  3072 template (the former print_mode reference), thus access becomes
  3073 non-critical.  The global print_mode reference is for session
  3074 management only; user-code should use print_mode_value,
  3075 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  3076 
  3077 * Functions system/system_out provide a robust way to invoke external
  3078 shell commands, with propagation of interrupts (requires Poly/ML
  3079 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  3080 
  3081 
  3082 *** System ***
  3083 
  3084 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  3085 in accordance with Proof General 3.7, which prefers GNU emacs.
  3086 
  3087 * isatool tty runs Isabelle process with plain tty interaction;
  3088 optional line editor may be specified via ISABELLE_LINE_EDITOR
  3089 setting, the default settings attempt to locate "ledit" and "rlwrap".
  3090 
  3091 * isatool browser now works with Cygwin as well, using general
  3092 "javapath" function defined in Isabelle process environment.
  3093 
  3094 * YXML notation provides a simple and efficient alternative to
  3095 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  3096 isatool yxml as described in the Isabelle system manual.
  3097 
  3098 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  3099 provides general wrapper for managing an Isabelle process in a robust
  3100 fashion, with ``cooked'' output from stdin/stderr.
  3101 
  3102 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  3103 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  3104 
  3105 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  3106 way of changing the user's settings is via
  3107 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  3108 script.
  3109 
  3110 * Multithreading.max_threads := 0 refers to the number of actual CPU
  3111 cores of the underlying machine, which is a good starting point for
  3112 optimal performance tuning.  The corresponding usedir option -M allows
  3113 "max" as an alias for "0".  WARNING: does not work on certain versions
  3114 of Mac OS (with Poly/ML 5.1).
  3115 
  3116 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  3117 adverse effect of Isabelle flooding interactive front-ends (notably
  3118 ProofGeneral / XEmacs).
  3119 
  3120 
  3121 
  3122 New in Isabelle2007 (November 2007)
  3123 -----------------------------------
  3124 
  3125 *** General ***
  3126 
  3127 * More uniform information about legacy features, notably a
  3128 warning/error of "Legacy feature: ...", depending on the state of the
  3129 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  3130 legacy features will disappear eventually.
  3131 
  3132 * Theory syntax: the header format ``theory A = B + C:'' has been
  3133 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  3134 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  3135 
  3136 * Theory syntax: the old non-Isar theory file format has been
  3137 discontinued altogether.  Note that ML proof scripts may still be used
  3138 with Isar theories; migration is usually quite simple with the ML
  3139 function use_legacy_bindings.  INCOMPATIBILITY.
  3140 
  3141 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  3142 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  3143 quotes.
  3144 
  3145 * Theory loader: be more serious about observing the static theory
  3146 header specifications (including optional directories), but not the
  3147 accidental file locations of previously successful loads.  The strict
  3148 update policy of former update_thy is now already performed by
  3149 use_thy, so the former has been removed; use_thys updates several
  3150 theories simultaneously, just as 'imports' within a theory header
  3151 specification, but without merging the results.  Potential
  3152 INCOMPATIBILITY: may need to refine theory headers and commands
  3153 ROOT.ML which depend on load order.
  3154 
  3155 * Theory loader: optional support for content-based file
  3156 identification, instead of the traditional scheme of full physical
  3157 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  3158 (cf. the system manual).  The new scheme allows to work with
  3159 non-finished theories in persistent session images, such that source
  3160 files may be moved later on without requiring reloads.
  3161 
  3162 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3163 file (with the same base name as the theory) are considered a legacy
  3164 feature, which will disappear eventually. Even now, the theory loader
  3165 no longer maintains dependencies on such files.
  3166 
  3167 * Syntax: the scope for resolving ambiguities via type-inference is
  3168 now limited to individual terms, instead of whole simultaneous
  3169 specifications as before. This greatly reduces the complexity of the
  3170 syntax module and improves flexibility by separating parsing and
  3171 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  3172 'fixes' etc.) are required in rare situations.
  3173 
  3174 * Syntax: constants introduced by new-style packages ('definition',
  3175 'abbreviation' etc.) are passed through the syntax module in
  3176 ``authentic mode''. This means that associated mixfix annotations
  3177 really stick to such constants, independently of potential name space
  3178 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  3179 trees are represented slightly differently, may need to adapt syntax
  3180 translations accordingly. Use CONST marker in 'translations' and
  3181 @{const_syntax} antiquotation in 'parse_translation' etc.
  3182 
  3183 * Legacy goal package: reduced interface to the bare minimum required
  3184 to keep existing proof scripts running.  Most other user-level
  3185 functions are now part of the OldGoals structure, which is *not* open
  3186 by default (consider isatool expandshort before open OldGoals).
  3187 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  3188 these tend to cause confusion about the actual goal (!) context being
  3189 used here, which is not necessarily the same as the_context().
  3190 
  3191 * Command 'find_theorems': supports "*" wild-card in "name:"
  3192 criterion; "with_dups" option.  Certain ProofGeneral versions might
  3193 support a specific search form (see ProofGeneral/CHANGES).
  3194 
  3195 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  3196 by default, which means that "prems" (and also "fixed variables") are
  3197 suppressed from proof state output.  Note that the ProofGeneral
  3198 settings mechanism allows to change and save options persistently, but
  3199 older versions of Isabelle will fail to start up if a negative prems
  3200 limit is imposed.
  3201 
  3202 * Local theory targets may be specified by non-nested blocks of
  3203 ``context/locale/class ... begin'' followed by ``end''.  The body may
  3204 contain definitions, theorems etc., including any derived mechanism
  3205 that has been implemented on top of these primitives.  This concept
  3206 generalizes the existing ``theorem (in ...)'' towards more versatility
  3207 and scalability.
  3208 
  3209 * Proof General interface: proper undo of final 'end' command;
  3210 discontinued Isabelle/classic mode (ML proof scripts).
  3211 
  3212 
  3213 *** Document preparation ***
  3214 
  3215 * Added antiquotation @{theory name} which prints the given name,
  3216 after checking that it refers to a valid ancestor theory in the
  3217 current context.
  3218 
  3219 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  3220 check the given source text as ML type/structure, printing verbatim.
  3221 
  3222 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  3223 "c args == rhs" given in the current context.  (Any number of
  3224 arguments may be given on the LHS.)
  3225 
  3226 
  3227 *** Pure ***
  3228 
  3229 * The 'class' package offers a combination of axclass and locale to
  3230 achieve Haskell-like type classes in Isabelle.  Definitions and
  3231 theorems within a class context produce both relative results (with
  3232 implicit parameters according to the locale context), and polymorphic
  3233 constants with qualified polymorphism (according to the class
  3234 context).  Within the body context of a 'class' target, a separate
  3235 syntax layer ("user space type system") takes care of converting
  3236 between global polymorphic consts and internal locale representation.
  3237 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  3238 "isatool doc classes" provides a tutorial.
  3239 
  3240 * Generic code generator framework allows to generate executable
  3241 code for ML and Haskell (including Isabelle classes).  A short usage
  3242 sketch:
  3243 
  3244     internal compilation:
  3245         export_code <list of constants (term syntax)> in SML
  3246     writing SML code to a file:
  3247         export_code <list of constants (term syntax)> in SML <filename>
  3248     writing OCaml code to a file:
  3249         export_code <list of constants (term syntax)> in OCaml <filename>
  3250     writing Haskell code to a bunch of files:
  3251         export_code <list of constants (term syntax)> in Haskell <filename>
  3252 
  3253     evaluating closed propositions to True/False using code generation:
  3254         method ``eval''
  3255 
  3256 Reasonable default setup of framework in HOL.
  3257 
  3258 Theorem attributs for selecting and transforming function equations theorems:
  3259 
  3260     [code fun]:        select a theorem as function equation for a specific constant
  3261     [code fun del]:    deselect a theorem as function equation for a specific constant
  3262     [code inline]:     select an equation theorem for unfolding (inlining) in place
  3263     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  3264 
  3265 User-defined serializations (target in {SML, OCaml, Haskell}):
  3266 
  3267     code_const <and-list of constants (term syntax)>
  3268       {(target) <and-list of const target syntax>}+
  3269 
  3270     code_type <and-list of type constructors>
  3271       {(target) <and-list of type target syntax>}+
  3272 
  3273     code_instance <and-list of instances>
  3274       {(target)}+
  3275         where instance ::= <type constructor> :: <class>
  3276 
  3277     code_class <and_list of classes>
  3278       {(target) <and-list of class target syntax>}+
  3279         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  3280 
  3281 code_instance and code_class only are effective to target Haskell.
  3282 
  3283 For example usage see src/HOL/ex/Codegenerator.thy and
  3284 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  3285 generation from Isabelle/HOL theories is available via "isatool doc
  3286 codegen".
  3287 
  3288 * Code generator: consts in 'consts_code' Isar commands are now
  3289 referred to by usual term syntax (including optional type
  3290 annotations).
  3291 
  3292 * Command 'no_translations' removes translation rules from theory
  3293 syntax.
  3294 
  3295 * Overloaded definitions are now actually checked for acyclic
  3296 dependencies.  The overloading scheme is slightly more general than
  3297 that of Haskell98, although Isabelle does not demand an exact
  3298 correspondence to type class and instance declarations.
  3299 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  3300 exotic versions of overloading -- at the discretion of the user!
  3301 
  3302 Polymorphic constants are represented via type arguments, i.e. the
  3303 instantiation that matches an instance against the most general
  3304 declaration given in the signature.  For example, with the declaration
  3305 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  3306 as c(nat).  Overloading is essentially simultaneous structural
  3307 recursion over such type arguments.  Incomplete specification patterns
  3308 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  3309 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  3310 Command 'print_theory' outputs the normalized system of recursive
  3311 equations, see section "definitions".
  3312 
  3313 * Configuration options are maintained within the theory or proof
  3314 context (with name and type bool/int/string), providing a very simple
  3315 interface to a poor-man's version of general context data.  Tools may
  3316 declare options in ML (e.g. using Attrib.config_int) and then refer to
  3317 these values using Config.get etc.  Users may change options via an
  3318 associated attribute of the same name.  This form of context
  3319 declaration works particularly well with commands 'declare' or
  3320 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  3321 very easy to avoid global references, which would not observe Isar
  3322 toplevel undo/redo and fail to work with multithreading.
  3323 
  3324 Various global ML references of Pure and HOL have been turned into
  3325 configuration options:
  3326 
  3327   Unify.search_bound		unify_search_bound
  3328   Unify.trace_bound		unify_trace_bound
  3329   Unify.trace_simp		unify_trace_simp
  3330   Unify.trace_types		unify_trace_types
  3331   Simplifier.simp_depth_limit	simp_depth_limit
  3332   Blast.depth_limit		blast_depth_limit
  3333   DatatypeProp.dtK		datatype_distinctness_limit
  3334   fast_arith_neq_limit  	fast_arith_neq_limit
  3335   fast_arith_split_limit	fast_arith_split_limit
  3336 
  3337 * Named collections of theorems may be easily installed as context
  3338 data using the functor NamedThmsFun (see also
  3339 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  3340 attributes; there is also a toplevel print command.  This facility is
  3341 just a common case of general context data, which is the preferred way
  3342 for anything more complex than just a list of facts in canonical
  3343 order.
  3344 
  3345 * Isar: command 'declaration' augments a local theory by generic
  3346 declaration functions written in ML.  This enables arbitrary content
  3347 being added to the context, depending on a morphism that tells the
  3348 difference of the original declaration context wrt. the application
  3349 context encountered later on.
  3350 
  3351 * Isar: proper interfaces for simplification procedures.  Command
  3352 'simproc_setup' declares named simprocs (with match patterns, and body
  3353 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  3354 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  3355 
  3356 * Isar: an extra pair of brackets around attribute declarations
  3357 abbreviates a theorem reference involving an internal dummy fact,
  3358 which will be ignored later --- only the effect of the attribute on
  3359 the background context will persist.  This form of in-place
  3360 declarations is particularly useful with commands like 'declare' and
  3361 'using', for example ``have A using [[simproc a]] by simp''.
  3362 
  3363 * Isar: method "assumption" (and implicit closing of subproofs) now
  3364 takes simple non-atomic goal assumptions into account: after applying
  3365 an assumption as a rule the resulting subgoals are solved by atomic
  3366 assumption steps.  This is particularly useful to finish 'obtain'
  3367 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  3368 without referring to the original premise "!!x. P x ==> thesis" in the
  3369 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  3370 more permissive.
  3371 
  3372 * Isar: implicit use of prems from the Isar proof context is
  3373 considered a legacy feature.  Common applications like ``have A .''
  3374 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  3375 referencing facts explicitly here improves readability and
  3376 maintainability of proof texts.
  3377 
  3378 * Isar: improper proof element 'guess' is like 'obtain', but derives
  3379 the obtained context from the course of reasoning!  For example:
  3380 
  3381   assume "EX x y. A x & B y"   -- "any previous fact"
  3382   then guess x and y by clarify
  3383 
  3384 This technique is potentially adventurous, depending on the facts and
  3385 proof tools being involved here.
  3386 
  3387 * Isar: known facts from the proof context may be specified as literal
  3388 propositions, using ASCII back-quote syntax.  This works wherever
  3389 named facts used to be allowed so far, in proof commands, proof
  3390 methods, attributes etc.  Literal facts are retrieved from the context
  3391 according to unification of type and term parameters.  For example,
  3392 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  3393 theorems in the current context, then these are valid literal facts:
  3394 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  3395 
  3396 There is also a proof method "fact" which does the same composition
  3397 for explicit goal states, e.g. the following proof texts coincide with
  3398 certain special cases of literal facts:
  3399 
  3400   have "A" by fact                 ==  note `A`
  3401   have "A ==> B" by fact           ==  note `A ==> B`
  3402   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  3403   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  3404 
  3405 * Isar: ":" (colon) is no longer a symbolic identifier character in
  3406 outer syntax.  Thus symbolic identifiers may be used without
  3407 additional white space in declarations like this: ``assume *: A''.
  3408 
  3409 * Isar: 'print_facts' prints all local facts of the current context,
  3410 both named and unnamed ones.
  3411 
  3412 * Isar: 'def' now admits simultaneous definitions, e.g.:
  3413 
  3414   def x == "t" and y == "u"
  3415 
  3416 * Isar: added command 'unfolding', which is structurally similar to
  3417 'using', but affects both the goal state and facts by unfolding given
  3418 rewrite rules.  Thus many occurrences of the 'unfold' method or
  3419 'unfolded' attribute may be replaced by first-class proof text.
  3420 
  3421 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  3422 and command 'unfolding' now all support object-level equalities
  3423 (potentially conditional).  The underlying notion of rewrite rule is
  3424 analogous to the 'rule_format' attribute, but *not* that of the
  3425 Simplifier (which is usually more generous).
  3426 
  3427 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  3428 premises of a theorem by n. Useful in conjunction with drule.
  3429 
  3430 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  3431 method expression within a sandbox consisting of the first N
  3432 sub-goals, which need to exist.  For example, ``simp_all [3]''
  3433 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  3434 simplifies all new goals that emerge from applying rule foo to the
  3435 originally first one.
  3436 
  3437 * Isar: schematic goals are no longer restricted to higher-order
  3438 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  3439 expected.
  3440 
  3441 * Isar: the conclusion of a long theorem statement is now either
  3442 'shows' (a simultaneous conjunction, as before), or 'obtains'
  3443 (essentially a disjunction of cases with local parameters and
  3444 assumptions).  The latter allows to express general elimination rules
  3445 adequately; in this notation common elimination rules look like this:
  3446 
  3447   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  3448     assumes "EX x. P x"
  3449     obtains x where "P x"
  3450 
  3451   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  3452     assumes "A & B"
  3453     obtains A and B
  3454 
  3455   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  3456     assumes "A | B"
  3457     obtains
  3458       A
  3459     | B
  3460 
  3461 The subsequent classical rules even refer to the formal "thesis"
  3462 explicitly:
  3463 
  3464   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  3465     obtains "~ thesis"
  3466 
  3467   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  3468     obtains "thesis ==> something"
  3469 
  3470 The actual proof of an 'obtains' statement is analogous to that of the
  3471 Isar proof element 'obtain', only that there may be several cases.
  3472 Optional case names may be specified in parentheses; these will be
  3473 available both in the present proof and as annotations in the
  3474 resulting rule, for later use with the 'cases' method (cf. attribute
  3475 case_names).
  3476 
  3477 * Isar: the assumptions of a long theorem statement are available as
  3478 "assms" fact in the proof context.  This is more appropriate than the
  3479 (historical) "prems", which refers to all assumptions of the current
  3480 context, including those from the target locale, proof body etc.
  3481 
  3482 * Isar: 'print_statement' prints theorems from the current theory or
  3483 proof context in long statement form, according to the syntax of a
  3484 top-level lemma.
  3485 
  3486 * Isar: 'obtain' takes an optional case name for the local context
  3487 introduction rule (default "that").
  3488 
  3489 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  3490 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  3491 to occur.
  3492 
  3493 * Pure: syntax "CONST name" produces a fully internalized constant
  3494 according to the current context.  This is particularly useful for
  3495 syntax translations that should refer to internal constant
  3496 representations independently of name spaces.
  3497 
  3498 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  3499 instead of "FOO ". This allows multiple binder declarations to coexist
  3500 in the same context.  INCOMPATIBILITY.
  3501 
  3502 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  3503 primitive that also works in a locale context (both for constants and
  3504 fixed variables). Type declaration and internal syntactic representation
  3505 of given constants retrieved from the context. Likewise, the
  3506 'no_notation' command allows to remove given syntax annotations from the
  3507 current context.
  3508 
  3509 * Isar/locales: new derived specification elements 'axiomatization',
  3510 'definition', 'abbreviation', which support type-inference, admit
  3511 object-level specifications (equality, equivalence).  See also the
  3512 isar-ref manual.  Examples:
  3513 
  3514   axiomatization
  3515     eq  (infix "===" 50) where
  3516     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  3517 
  3518   definition "f x y = x + y + 1"
  3519   definition g where "g x = f x x"
  3520 
  3521   abbreviation
  3522     neq  (infix "=!=" 50) where
  3523     "x =!= y == ~ (x === y)"
  3524 
  3525 These specifications may be also used in a locale context.  Then the
  3526 constants being introduced depend on certain fixed parameters, and the
  3527 constant name is qualified by the locale base name.  An internal
  3528 abbreviation takes care for convenient input and output, making the
  3529 parameters implicit and using the original short name.  See also
  3530 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  3531 entities from a monomorphic theory.
  3532 
  3533 Presently, abbreviations are only available 'in' a target locale, but
  3534 not inherited by general import expressions.  Also note that
  3535 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  3536 'translations' in common applications.  The "no_abbrevs" print mode
  3537 prevents folding of abbreviations in term output.
  3538 
  3539 Concrete syntax is attached to specified constants in internal form,
  3540 independently of name spaces.  The parse tree representation is
  3541 slightly different -- use 'notation' instead of raw 'syntax', and
  3542 'translations' with explicit "CONST" markup to accommodate this.
  3543 
  3544 * Pure/Isar: unified syntax for new-style specification mechanisms
  3545 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  3546 full type inference and dummy patterns ("_").  For example:
  3547 
  3548   definition "K x _ = x"
  3549 
  3550   inductive conj for A B
  3551   where "A ==> B ==> conj A B"
  3552 
  3553 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  3554 the current context.  Print mode "no_abbrevs" prevents inversion of
  3555 abbreviations on output.
  3556 
  3557 * Isar/locales: improved parameter handling: use of locales "var" and
  3558 "struct" no longer necessary; - parameter renamings are no longer
  3559 required to be injective.  For example, this allows to define
  3560 endomorphisms as locale endom = homom mult mult h.
  3561 
  3562 * Isar/locales: changed the way locales with predicates are defined.
  3563 Instead of accumulating the specification, the imported expression is
  3564 now an interpretation.  INCOMPATIBILITY: different normal form of
  3565 locale expressions.  In particular, in interpretations of locales with
  3566 predicates, goals repesenting already interpreted fragments are not
  3567 removed automatically.  Use methods `intro_locales' and
  3568 `unfold_locales'; see below.
  3569 
  3570 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  3571 provide backward reasoning on locales predicates.  The methods are
  3572 aware of interpretations and discharge corresponding goals.
  3573 `intro_locales' is less aggressive then `unfold_locales' and does not
  3574 unfold predicates to assumptions.
  3575 
  3576 * Isar/locales: the order in which locale fragments are accumulated
  3577 has changed.  This enables to override declarations from fragments due
  3578 to interpretations -- for example, unwanted simp rules.
  3579 
  3580 * Isar/locales: interpretation in theories and proof contexts has been
  3581 extended.  One may now specify (and prove) equations, which are
  3582 unfolded in interpreted theorems.  This is useful for replacing
  3583 defined concepts (constants depending on locale parameters) by
  3584 concepts already existing in the target context.  Example:
  3585 
  3586   interpretation partial_order ["op <= :: [int, int] => bool"]
  3587     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3588 
  3589 Typically, the constant `partial_order.less' is created by a
  3590 definition specification element in the context of locale
  3591 partial_order.
  3592 
  3593 * Method "induct": improved internal context management to support
  3594 local fixes and defines on-the-fly. Thus explicit meta-level
  3595 connectives !!  and ==> are rarely required anymore in inductive goals
  3596 (using object-logic connectives for this purpose has been long
  3597 obsolete anyway). Common proof patterns are explained in
  3598 src/HOL/Induct/Common_Patterns.thy, see also
  3599 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3600 examples.
  3601 
  3602 * Method "induct": improved handling of simultaneous goals. Instead of
  3603 introducing object-level conjunction, the statement is now split into
  3604 several conclusions, while the corresponding symbolic cases are nested
  3605 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3606 see src/HOL/Induct/Common_Patterns.thy, for example.
  3607 
  3608 * Method "induct": mutual induction rules are now specified as a list
  3609 of rule sharing the same induction cases. HOL packages usually provide
  3610 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3611 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3612 mutual induction rules differently, i.e. like this:
  3613 
  3614   (induct rule: foo_bar.inducts)
  3615   (induct set: foo bar)
  3616   (induct pred: foo bar)
  3617   (induct type: foo bar)
  3618 
  3619 The ML function ProjectRule.projections turns old-style rules into the
  3620 new format.
  3621 
  3622 * Method "coinduct": dual of induction, see
  3623 src/HOL/Library/Coinductive_List.thy for various examples.
  3624 
  3625 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3626 considered a legacy feature.
  3627 
  3628 * Attribute "symmetric" produces result with standardized schematic
  3629 variables (index 0).  Potential INCOMPATIBILITY.
  3630 
  3631 * Simplifier: by default the simplifier trace only shows top level
  3632 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3633 default. Thus there is less danger of being flooded by the trace. The
  3634 trace indicates where parts have been suppressed.
  3635   
  3636 * Provers/classical: removed obsolete classical version of elim_format
  3637 attribute; classical elim/dest rules are now treated uniformly when
  3638 manipulating the claset.
  3639 
  3640 * Provers/classical: stricter checks to ensure that supplied intro,
  3641 dest and elim rules are well-formed; dest and elim rules must have at
  3642 least one premise.
  3643 
  3644 * Provers/classical: attributes dest/elim/intro take an optional
  3645 weight argument for the rule (just as the Pure versions).  Weights are
  3646 ignored by automated tools, but determine the search order of single
  3647 rule steps.
  3648 
  3649 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3650 where the body does not mention the bound variable.  Note that dummy
  3651 patterns implicitly depend on their context of bounds, which makes
  3652 "{_. _}" match any set comprehension as expected.  Potential
  3653 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3654 constant "_idtdummy" in the binding position.
  3655 
  3656 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3657 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3658 for example "A -> B" => "Pi A (%_. B)".
  3659 
  3660 * Pure: 'class_deps' command visualizes the subclass relation, using
  3661 the graph browser tool.
  3662 
  3663 * Pure: 'print_theory' now suppresses certain internal declarations by
  3664 default; use '!' option for full details.
  3665 
  3666 
  3667 *** HOL ***
  3668 
  3669 * Method "metis" proves goals by applying the Metis general-purpose
  3670 resolution prover (see also http://gilith.com/software/metis/).
  3671 Examples are in the directory MetisExamples.  WARNING: the
  3672 Isabelle/HOL-Metis integration does not yet work properly with
  3673 multi-threading.
  3674   
  3675 * Command 'sledgehammer' invokes external automatic theorem provers as
  3676 background processes.  It generates calls to the "metis" method if
  3677 successful. These can be pasted into the proof.  Users do not have to
  3678 wait for the automatic provers to return.  WARNING: does not really
  3679 work with multi-threading.
  3680 
  3681 * New "auto_quickcheck" feature tests outermost goal statements for
  3682 potential counter-examples.  Controlled by ML references
  3683 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3684 5000 milliseconds).  Fails silently if statements is outside of
  3685 executable fragment, or any other codgenerator problem occurs.
  3686 
  3687 * New constant "undefined" with axiom "undefined x = undefined".
  3688 
  3689 * Added class "HOL.eq", allowing for code generation with polymorphic
  3690 equality.
  3691 
  3692 * Some renaming of class constants due to canonical name prefixing in
  3693 the new 'class' package:
  3694 
  3695     HOL.abs ~> HOL.abs_class.abs
  3696     HOL.divide ~> HOL.divide_class.divide
  3697     0 ~> HOL.zero_class.zero
  3698     1 ~> HOL.one_class.one
  3699     op + ~> HOL.plus_class.plus
  3700     op - ~> HOL.minus_class.minus
  3701     uminus ~> HOL.minus_class.uminus
  3702     op * ~> HOL.times_class.times
  3703     op < ~> HOL.ord_class.less
  3704     op <= > HOL.ord_class.less_eq
  3705     Nat.power ~> Power.power_class.power
  3706     Nat.size ~> Nat.size_class.size
  3707     Numeral.number_of ~> Numeral.number_class.number_of
  3708     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3709     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3710     Orderings.min ~> Orderings.ord_class.min
  3711     Orderings.max ~> Orderings.ord_class.max
  3712     Divides.op div ~> Divides.div_class.div
  3713     Divides.op mod ~> Divides.div_class.mod
  3714     Divides.op dvd ~> Divides.div_class.dvd
  3715 
  3716 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3717 
  3718 a) User-defined constants using any of the names "plus", "minus",
  3719 "times", "less" or "less_eq". The standard syntax translations for
  3720 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3721 names.
  3722 
  3723 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3724 INCOMPATIBILITY: use more specific names.
  3725 
  3726 c) Permutative equations (e.g. "a + b = b + a")
  3727 Since the change of names also changes the order of terms, permutative
  3728 rewrite rules may get applied in a different order. Experience shows
  3729 that this is rarely the case (only two adaptions in the whole Isabelle
  3730 distribution).  INCOMPATIBILITY: rewrite proofs
  3731 
  3732 d) ML code directly refering to constant names
  3733 This in general only affects hand-written proof tactics, simprocs and
  3734 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3735 Consider using @{const_name} antiquotation.
  3736 
  3737 * New class "default" with associated constant "default".
  3738 
  3739 * Function "sgn" is now overloaded and available on int, real, complex
  3740 (and other numeric types), using class "sgn".  Two possible defs of
  3741 sgn are given as equational assumptions in the classes sgn_if and
  3742 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3743 INCOMPATIBILITY.
  3744 
  3745 * Locale "partial_order" now unified with class "order" (cf. theory
  3746 Orderings), added parameter "less".  INCOMPATIBILITY.
  3747 
  3748 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3749 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3750 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3751 
  3752 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3753 changed order of proof goals in instance proofs.
  3754 
  3755 * The transitivity reasoner for partial and linear orders is set up
  3756 for classes "order" and "linorder".  Instances of the reasoner are available
  3757 in all contexts importing or interpreting the corresponding locales.
  3758 Method "order" invokes the reasoner separately; the reasoner
  3759 is also integrated with the Simplifier as a solver.  Diagnostic
  3760 command 'print_orders' shows the available instances of the reasoner
  3761 in the current context.
  3762 
  3763 * Localized monotonicity predicate in theory "Orderings"; integrated
  3764 lemmas max_of_mono and min_of_mono with this predicate.
  3765 INCOMPATIBILITY.
  3766 
  3767 * Formulation of theorem "dense" changed slightly due to integration
  3768 with new class dense_linear_order.
  3769 
  3770 * Uniform lattice theory development in HOL.
  3771 
  3772     constants "meet" and "join" now named "inf" and "sup"
  3773     constant "Meet" now named "Inf"
  3774 
  3775     classes "meet_semilorder" and "join_semilorder" now named
  3776       "lower_semilattice" and "upper_semilattice"
  3777     class "lorder" now named "lattice"
  3778     class "comp_lat" now named "complete_lattice"
  3779 
  3780     Instantiation of lattice classes allows explicit definitions
  3781     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3782 
  3783   INCOMPATIBILITY.  Theorem renames:
  3784 
  3785     meet_left_le            ~> inf_le1
  3786     meet_right_le           ~> inf_le2
  3787     join_left_le            ~> sup_ge1
  3788     join_right_le           ~> sup_ge2
  3789     meet_join_le            ~> inf_sup_ord
  3790     le_meetI                ~> le_infI
  3791     join_leI                ~> le_supI
  3792     le_meet                 ~> le_inf_iff
  3793     le_join                 ~> ge_sup_conv
  3794     meet_idempotent         ~> inf_idem
  3795     join_idempotent         ~> sup_idem
  3796     meet_comm               ~> inf_commute
  3797     join_comm               ~> sup_commute
  3798     meet_leI1               ~> le_infI1
  3799     meet_leI2               ~> le_infI2
  3800     le_joinI1               ~> le_supI1
  3801     le_joinI2               ~> le_supI2
  3802     meet_assoc              ~> inf_assoc
  3803     join_assoc              ~> sup_assoc
  3804     meet_left_comm          ~> inf_left_commute
  3805     meet_left_idempotent    ~> inf_left_idem
  3806     join_left_comm          ~> sup_left_commute
  3807     join_left_idempotent    ~> sup_left_idem
  3808     meet_aci                ~> inf_aci
  3809     join_aci                ~> sup_aci
  3810     le_def_meet             ~> le_iff_inf
  3811     le_def_join             ~> le_iff_sup
  3812     join_absorp2            ~> sup_absorb2
  3813     join_absorp1            ~> sup_absorb1
  3814     meet_absorp1            ~> inf_absorb1
  3815     meet_absorp2            ~> inf_absorb2
  3816     meet_join_absorp        ~> inf_sup_absorb
  3817     join_meet_absorp        ~> sup_inf_absorb
  3818     distrib_join_le         ~> distrib_sup_le
  3819     distrib_meet_le         ~> distrib_inf_le
  3820 
  3821     add_meet_distrib_left   ~> add_inf_distrib_left
  3822     add_join_distrib_left   ~> add_sup_distrib_left
  3823     is_join_neg_meet        ~> is_join_neg_inf
  3824     is_meet_neg_join        ~> is_meet_neg_sup
  3825     add_meet_distrib_right  ~> add_inf_distrib_right
  3826     add_join_distrib_right  ~> add_sup_distrib_right
  3827     add_meet_join_distribs  ~> add_sup_inf_distribs
  3828     join_eq_neg_meet        ~> sup_eq_neg_inf
  3829     meet_eq_neg_join        ~> inf_eq_neg_sup
  3830     add_eq_meet_join        ~> add_eq_inf_sup
  3831     meet_0_imp_0            ~> inf_0_imp_0
  3832     join_0_imp_0            ~> sup_0_imp_0
  3833     meet_0_eq_0             ~> inf_0_eq_0
  3834     join_0_eq_0             ~> sup_0_eq_0
  3835     neg_meet_eq_join        ~> neg_inf_eq_sup
  3836     neg_join_eq_meet        ~> neg_sup_eq_inf
  3837     join_eq_if              ~> sup_eq_if
  3838 
  3839     mono_meet               ~> mono_inf
  3840     mono_join               ~> mono_sup
  3841     meet_bool_eq            ~> inf_bool_eq
  3842     join_bool_eq            ~> sup_bool_eq
  3843     meet_fun_eq             ~> inf_fun_eq
  3844     join_fun_eq             ~> sup_fun_eq
  3845     meet_set_eq             ~> inf_set_eq
  3846     join_set_eq             ~> sup_set_eq
  3847     meet1_iff               ~> inf1_iff
  3848     meet2_iff               ~> inf2_iff
  3849     meet1I                  ~> inf1I
  3850     meet2I                  ~> inf2I
  3851     meet1D1                 ~> inf1D1
  3852     meet2D1                 ~> inf2D1
  3853     meet1D2                 ~> inf1D2
  3854     meet2D2                 ~> inf2D2
  3855     meet1E                  ~> inf1E
  3856     meet2E                  ~> inf2E
  3857     join1_iff               ~> sup1_iff
  3858     join2_iff               ~> sup2_iff
  3859     join1I1                 ~> sup1I1
  3860     join2I1                 ~> sup2I1
  3861     join1I1                 ~> sup1I1
  3862     join2I2                 ~> sup1I2
  3863     join1CI                 ~> sup1CI
  3864     join2CI                 ~> sup2CI
  3865     join1E                  ~> sup1E
  3866     join2E                  ~> sup2E
  3867 
  3868     is_meet_Meet            ~> is_meet_Inf
  3869     Meet_bool_def           ~> Inf_bool_def
  3870     Meet_fun_def            ~> Inf_fun_def
  3871     Meet_greatest           ~> Inf_greatest
  3872     Meet_lower              ~> Inf_lower
  3873     Meet_set_def            ~> Inf_set_def
  3874 
  3875     Sup_def                 ~> Sup_Inf
  3876     Sup_bool_eq             ~> Sup_bool_def
  3877     Sup_fun_eq              ~> Sup_fun_def
  3878     Sup_set_eq              ~> Sup_set_def
  3879 
  3880     listsp_meetI            ~> listsp_infI
  3881     listsp_meet_eq          ~> listsp_inf_eq
  3882 
  3883     meet_min                ~> inf_min
  3884     join_max                ~> sup_max
  3885 
  3886 * Added syntactic class "size"; overloaded constant "size" now has
  3887 type "'a::size ==> bool"
  3888 
  3889 * Internal reorganisation of `size' of datatypes: size theorems
  3890 "foo.size" are no longer subsumed by "foo.simps" (but are still
  3891 simplification rules by default!); theorems "prod.size" now named
  3892 "*.size".
  3893 
  3894 * Class "div" now inherits from class "times" rather than "type".
  3895 INCOMPATIBILITY.
  3896 
  3897 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  3898 Linorder etc.  have disappeared; operations defined in terms of
  3899 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  3900 
  3901 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  3902 
  3903 * HOL-Word: New extensive library and type for generic, fixed size
  3904 machine words, with arithemtic, bit-wise, shifting and rotating
  3905 operations, reflection into int, nat, and bool lists, automation for
  3906 linear arithmetic (by automatic reflection into nat or int), including
  3907 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  3908 arithmetic type classes, supporting automatic simplification of
  3909 numerals on all operations.
  3910 
  3911 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  3912 
  3913 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  3914 
  3915 * Code generator library theories:
  3916   - Code_Integer represents HOL integers by big integer literals in target
  3917     languages.
  3918   - Code_Char represents HOL characters by character literals in target
  3919     languages.
  3920   - Code_Char_chr like Code_Char, but also offers treatment of character
  3921     codes; includes Code_Integer.
  3922   - Executable_Set allows to generate code for finite sets using lists.
  3923   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  3924     denominator).
  3925   - Executable_Real implements a subset of real numbers, namly those
  3926     representable by rational numbers.
  3927   - Efficient_Nat implements natural numbers by integers, which in general will
  3928     result in higher efficency; pattern matching with 0/Suc is eliminated;
  3929     includes Code_Integer.
  3930   - Code_Index provides an additional datatype index which is mapped to
  3931     target-language built-in integers.
  3932   - Code_Message provides an additional datatype message_string which is isomorphic to
  3933     strings; messages are mapped to target-language strings.
  3934 
  3935 * New package for inductive predicates
  3936 
  3937   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  3938 
  3939     inductive
  3940       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3941       for z_1 :: U_1 and ... and z_n :: U_m
  3942     where
  3943       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3944     | ...
  3945 
  3946   with full support for type-inference, rather than
  3947 
  3948     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3949 
  3950     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3951     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3952 
  3953     inductive "s z_1 ... z_m"
  3954     intros
  3955       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3956       ...
  3957 
  3958   For backward compatibility, there is a wrapper allowing inductive
  3959   sets to be defined with the new package via
  3960 
  3961     inductive_set
  3962       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3963       for z_1 :: U_1 and ... and z_n :: U_m
  3964     where
  3965       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3966     | ...
  3967 
  3968   or
  3969 
  3970     inductive_set
  3971       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3972       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3973       for z_1 :: U_1 and ... and z_n :: U_m
  3974     where
  3975       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3976     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3977     | ...
  3978 
  3979   if the additional syntax "p ..." is required.
  3980 
  3981   Numerous examples can be found in the subdirectories src/HOL/Auth,
  3982   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  3983 
  3984   INCOMPATIBILITIES:
  3985 
  3986   - Since declaration and definition of inductive sets or predicates
  3987     is no longer separated, abbreviations involving the newly
  3988     introduced sets or predicates must be specified together with the
  3989     introduction rules after the 'where' keyword (see above), rather
  3990     than before the actual inductive definition.
  3991 
  3992   - The variables in induction and elimination rules are now
  3993     quantified in the order of their occurrence in the introduction
  3994     rules, rather than in alphabetical order. Since this may break
  3995     some proofs, these proofs either have to be repaired, e.g. by
  3996     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  3997     statements of the form
  3998 
  3999       case (rule_i a_i_1 ... a_i_{k_i})
  4000 
  4001     or the old order of quantification has to be restored by explicitly adding
  4002     meta-level quantifiers in the introduction rules, i.e.
  4003 
  4004       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  4005 
  4006   - The format of the elimination rules is now
  4007 
  4008       p z_1 ... z_m x_1 ... x_n ==>
  4009         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4010         ==> ... ==> P
  4011 
  4012     for predicates and
  4013 
  4014       (x_1, ..., x_n) : s z_1 ... z_m ==>
  4015         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4016         ==> ... ==> P
  4017 
  4018     for sets rather than
  4019 
  4020       x : s z_1 ... z_m ==>
  4021         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  4022         ==> ... ==> P
  4023 
  4024     This may require terms in goals to be expanded to n-tuples
  4025     (e.g. using case_tac or simplification with the split_paired_all
  4026     rule) before the above elimination rule is applicable.
  4027 
  4028   - The elimination or case analysis rules for (mutually) inductive
  4029     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  4030     list of rules "p_1_..._p_k.elims" is no longer available.
  4031 
  4032 * New package "function"/"fun" for general recursive functions,
  4033 supporting mutual and nested recursion, definitions in local contexts,
  4034 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  4035 for small examples, and the separate tutorial on the function
  4036 package. The old recdef "package" is still available as before, but
  4037 users are encouraged to use the new package.
  4038 
  4039 * Method "lexicographic_order" automatically synthesizes termination
  4040 relations as lexicographic combinations of size measures. 
  4041 
  4042 * Case-expressions allow arbitrary constructor-patterns (including
  4043 "_") and take their order into account, like in functional
  4044 programming.  Internally, this is translated into nested
  4045 case-expressions; missing cases are added and mapped to the predefined
  4046 constant "undefined". In complicated cases printing may no longer show
  4047 the original input but the internal form. Lambda-abstractions allow
  4048 the same form of pattern matching: "% pat1 => e1 | ..." is an
  4049 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  4050 variable.
  4051 
  4052 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  4053 is an abbreviation for "of_nat :: nat => int". The simplification
  4054 rules for "of_nat" have been changed to work like "int" did
  4055 previously.  Potential INCOMPATIBILITY:
  4056   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  4057   - of_nat_diff and of_nat_mult are no longer default simp rules
  4058 
  4059 * Method "algebra" solves polynomial equations over (semi)rings using
  4060 Groebner bases. The (semi)ring structure is defined by locales and the
  4061 tool setup depends on that generic context. Installing the method for
  4062 a specific type involves instantiating the locale and possibly adding
  4063 declarations for computation on the coefficients.  The method is
  4064 already instantiated for natural numbers and for the axiomatic class
  4065 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  4066 CALCULEMUS 2007 for the general principles underlying this
  4067 architecture of context-aware proof-tools.
  4068 
  4069 * Method "ferrack" implements quantifier elimination over
  4070 special-purpose dense linear orders using locales (analogous to
  4071 "algebra"). The method is already installed for class
  4072 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  4073 rat, etc.
  4074 
  4075 * Former constant "List.op @" now named "List.append".  Use ML
  4076 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  4077 circumvent possible incompatibilities when working on ML level.
  4078 
  4079 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  4080 
  4081 * New function listsum :: 'a list => 'a for arbitrary monoids.
  4082 Special syntax: "SUM x <- xs. f x" (and latex variants)
  4083 
  4084 * New syntax for Haskell-like list comprehension (input only), eg.
  4085 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  4086 
  4087 * The special syntax for function "filter" has changed from [x :
  4088 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  4089 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  4090 
  4091 * [a..b] is now defined for arbitrary linear orders.  It used to be
  4092 defined on nat only, as an abbreviation for [a..<Suc b]
  4093 INCOMPATIBILITY.
  4094 
  4095 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  4096 
  4097 * New functions "sorted" and "sort" in src/HOL/List.thy.
  4098 
  4099 * New lemma collection field_simps (an extension of ring_simps) for
  4100 manipulating (in)equations involving division. Multiplies with all
  4101 denominators that can be proved to be non-zero (in equations) or
  4102 positive/negative (in inequations).
  4103 
  4104 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  4105 have been improved and renamed to ring_simps, group_simps and
  4106 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  4107 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  4108 
  4109 * Theory Library/Commutative_Ring: switched from recdef to function
  4110 package; constants add, mul, pow now curried.  Infix syntax for
  4111 algebraic operations.
  4112 
  4113 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  4114 INCOMPATIBILITY.
  4115 
  4116 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  4117 INCOMPATIBILITY.
  4118 
  4119 * HOL/records: generalised field-update to take a function on the
  4120 field rather than the new value: r(|A := x|) is translated to A_update
  4121 (K x) r The K-combinator that is internally used is called K_record.
  4122 INCOMPATIBILITY: Usage of the plain update functions has to be
  4123 adapted.
  4124  
  4125 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  4126 * x = 0, which are required for a semiring.  Richer structures do not
  4127 inherit from semiring_0 anymore, because this property is a theorem
  4128 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  4129 there is more to prove, but this is mostly trivial.
  4130 
  4131 * Class "recpower" is generalized to arbitrary monoids, not just
  4132 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  4133 commutativity or semiring properties additionally.
  4134 
  4135 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  4136 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  4137 better use 'abbreviation'.
  4138 
  4139 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  4140 
  4141 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  4142 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  4143 significant changes for setting up numeral syntax for types:
  4144   - New constants Numeral.pred and Numeral.succ instead
  4145       of former Numeral.bin_pred and Numeral.bin_succ.
  4146   - Use integer operations instead of bin_add, bin_mult and so on.
  4147   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  4148   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  4149 
  4150 See src/HOL/Integ/IntArith.thy for an example setup.
  4151 
  4152 * Command 'normal_form' computes the normal form of a term that may
  4153 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  4154 produces ``[b, c, a]'' (without proof).  This command is suitable for
  4155 heavy-duty computations because the functions are compiled to ML
  4156 first.  Correspondingly, a method "normalization" is provided.  See
  4157 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  4158 
  4159 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  4160 25 like -->); output depends on the "iff" print_mode, the default is
  4161 "A = B" (with priority 50).
  4162 
  4163 * Relations less (<) and less_eq (<=) are also available on type bool.
  4164 Modified syntax to disallow nesting without explicit parentheses,
  4165 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  4166 INCOMPATIBILITY.
  4167 
  4168 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  4169 
  4170 * Relation composition operator "op O" now has precedence 75 and binds
  4171 stronger than union and intersection. INCOMPATIBILITY.
  4172 
  4173 * The old set interval syntax "{m..n(}" (and relatives) has been
  4174 removed.  Use "{m..<n}" (and relatives) instead.
  4175 
  4176 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  4177 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  4178 ``declare [[simproc del: neq]]''.
  4179 
  4180 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  4181 True/False.
  4182 
  4183 * Theorem Cons_eq_map_conv no longer declared as "simp".
  4184 
  4185 * Theorem setsum_mult renamed to setsum_right_distrib.
  4186 
  4187 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  4188 ``rule'' method.
  4189 
  4190 * Reimplemented methods "sat" and "satx", with several improvements:
  4191 goals no longer need to be stated as "<prems> ==> False", equivalences
  4192 (i.e. "=" on type bool) are handled, variable names of the form
  4193 "lit_<n>" are no longer reserved, significant speedup.
  4194 
  4195 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  4196 zChaff is still supported as well.
  4197 
  4198 * 'inductive' and 'datatype': provide projections of mutual rules,
  4199 bundled as foo_bar.inducts;
  4200 
  4201 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  4202 Library.
  4203 
  4204 * Library: moved theory Accessible_Part to main HOL.
  4205 
  4206 * Library: added theory Coinductive_List of potentially infinite lists
  4207 as greatest fixed-point.
  4208 
  4209 * Library: added theory AssocList which implements (finite) maps as
  4210 association lists.
  4211 
  4212 * Method "evaluation" solves goals (i.e. a boolean expression)
  4213 efficiently by compiling it to ML.  The goal is "proved" (via an
  4214 oracle) if it evaluates to True.
  4215 
  4216 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  4217 also when invoked by the simplifier.  This results in the Simplifier
  4218 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  4219 Configuration option fast_arith_split_limit=0 recovers the old
  4220 behavior.
  4221 
  4222 * Support for hex (0x20) and binary (0b1001) numerals.
  4223 
  4224 * New method: reify eqs (t), where eqs are equations for an
  4225 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  4226 parameter, computes a term s::'b and a list xs::'a list and proves the
  4227 theorem I xs s = t. This is also known as reification or quoting. The
  4228 resulting theorem is applied to the subgoal to substitute t with I xs
  4229 s.  If t is omitted, the subgoal itself is reified.
  4230 
  4231 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  4232 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  4233 where f is supposed to be a computable function (in the sense of code
  4234 generattion). The method uses reify to compute s and xs as above then
  4235 applies corr_thm and uses normalization by evaluation to "prove" f s =
  4236 r and finally gets the theorem t = r, which is again applied to the
  4237 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  4238 
  4239 * Reflection: Automatic reification now handels binding, an example is
  4240 available in src/HOL/ex/ReflectionEx.thy
  4241 
  4242 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  4243 command 'statespace' that is similar to 'record', but introduces an
  4244 abstract specification based on the locale infrastructure instead of
  4245 HOL types.  This leads to extra flexibility in composing state spaces,
  4246 in particular multiple inheritance and renaming of components.
  4247 
  4248 
  4249 *** HOL-Complex ***
  4250 
  4251 * Hyperreal: Functions root and sqrt are now defined on negative real
  4252 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  4253 Nonnegativity side conditions have been removed from many lemmas, so
  4254 that more subgoals may now be solved by simplification; potential
  4255 INCOMPATIBILITY.
  4256 
  4257 * Real: new type classes formalize real normed vector spaces and
  4258 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  4259 and norm :: 'a => real.
  4260 
  4261 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  4262 reals into other types. The overloaded constant Reals :: 'a set is now
  4263 defined as range of_real; potential INCOMPATIBILITY.
  4264 
  4265 * Real: proper support for ML code generation, including 'quickcheck'.
  4266 Reals are implemented as arbitrary precision rationals.
  4267 
  4268 * Hyperreal: Several constants that previously worked only for the
  4269 reals have been generalized, so they now work over arbitrary vector
  4270 spaces. Type annotations may need to be added in some cases; potential
  4271 INCOMPATIBILITY.
  4272 
  4273   Infinitesimal  :: ('a::real_normed_vector) star set
  4274   HFinite        :: ('a::real_normed_vector) star set
  4275   HInfinite      :: ('a::real_normed_vector) star set
  4276   approx         :: ('a::real_normed_vector) star => 'a star => bool
  4277   monad          :: ('a::real_normed_vector) star => 'a star set
  4278   galaxy         :: ('a::real_normed_vector) star => 'a star set
  4279   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  4280   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  4281   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  4282   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  4283   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  4284   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  4285   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  4286   sgn            :: 'a::real_normed_vector => 'a
  4287   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  4288 
  4289 * Complex: Some complex-specific constants are now abbreviations for
  4290 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  4291 hnorm.  Other constants have been entirely removed in favor of the
  4292 polymorphic versions (INCOMPATIBILITY):
  4293 
  4294   approx        <-- capprox
  4295   HFinite       <-- CFinite
  4296   HInfinite     <-- CInfinite
  4297   Infinitesimal <-- CInfinitesimal
  4298   monad         <-- cmonad
  4299   galaxy        <-- cgalaxy
  4300   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  4301   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  4302   (ns)deriv     <-- (ns)cderiv
  4303 
  4304 
  4305 *** HOL-Algebra ***
  4306 
  4307 * Formalisation of ideals and the quotient construction over rings.
  4308 
  4309 * Order and lattice theory no longer based on records.
  4310 INCOMPATIBILITY.
  4311 
  4312 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  4313 greatest_closed.  INCOMPATIBILITY.
  4314 
  4315 * Method algebra is now set up via an attribute.  For examples see
  4316 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  4317 of algebraic structures.
  4318 
  4319 * Renamed theory CRing to Ring.
  4320 
  4321 
  4322 *** HOL-Nominal ***
  4323 
  4324 * Substantial, yet incomplete support for nominal datatypes (binding
  4325 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  4326 src/HOL/Nominal/Examples.  Prospective users should consult
  4327 http://isabelle.in.tum.de/nominal/
  4328 
  4329 
  4330 *** ML ***
  4331 
  4332 * ML basics: just one true type int, which coincides with IntInf.int
  4333 (even on SML/NJ).
  4334 
  4335 * ML within Isar: antiquotations allow to embed statically-checked
  4336 formal entities in the source, referring to the context available at
  4337 compile-time.  For example:
  4338 
  4339 ML {* @{sort "{zero,one}"} *}
  4340 ML {* @{typ "'a => 'b"} *}
  4341 ML {* @{term "%x. x"} *}
  4342 ML {* @{prop "x == y"} *}
  4343 ML {* @{ctyp "'a => 'b"} *}
  4344 ML {* @{cterm "%x. x"} *}
  4345 ML {* @{cprop "x == y"} *}
  4346 ML {* @{thm asm_rl} *}
  4347 ML {* @{thms asm_rl} *}
  4348 ML {* @{type_name c} *}
  4349 ML {* @{type_syntax c} *}
  4350 ML {* @{const_name c} *}
  4351 ML {* @{const_syntax c} *}
  4352 ML {* @{context} *}
  4353 ML {* @{theory} *}
  4354 ML {* @{theory Pure} *}
  4355 ML {* @{theory_ref} *}
  4356 ML {* @{theory_ref Pure} *}
  4357 ML {* @{simpset} *}
  4358 ML {* @{claset} *}
  4359 ML {* @{clasimpset} *}
  4360 
  4361 The same works for sources being ``used'' within an Isar context.
  4362 
  4363 * ML in Isar: improved error reporting; extra verbosity with
  4364 ML_Context.trace enabled.
  4365 
  4366 * Pure/General/table.ML: the join operations now works via exceptions
  4367 DUP/SAME instead of type option. This is simpler in simple cases, and
  4368 admits slightly more efficient complex applications.
  4369 
  4370 * Pure: 'advanced' translation functions (parse_translation etc.) now
  4371 use Context.generic instead of just theory.
  4372 
  4373 * Pure: datatype Context.generic joins theory/Proof.context and
  4374 provides some facilities for code that works in either kind of
  4375 context, notably GenericDataFun for uniform theory and proof data.
  4376 
  4377 * Pure: simplified internal attribute type, which is now always
  4378 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  4379 local (Proof.context) attributes have been discontinued, while
  4380 minimizing code duplication. Thm.rule_attribute and
  4381 Thm.declaration_attribute build canonical attributes; see also structure
  4382 Context for further operations on Context.generic, notably
  4383 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  4384 declarations and definitions.
  4385 
  4386 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  4387 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  4388 init only required for impure data. INCOMPATIBILITY: empty really need
  4389 to be empty (no dependencies on theory content!)
  4390 
  4391 * Pure/kernel: consts certification ignores sort constraints given in
  4392 signature declarations. (This information is not relevant to the
  4393 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  4394 potential INCOMPATIBILITY.
  4395 
  4396 * Pure: axiomatic type classes are now purely definitional, with
  4397 explicit proofs of class axioms and super class relations performed
  4398 internally. See Pure/axclass.ML for the main internal interfaces --
  4399 notably AxClass.define_class supercedes AxClass.add_axclass, and
  4400 AxClass.axiomatize_class/classrel/arity supersede
  4401 Sign.add_classes/classrel/arities.
  4402 
  4403 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  4404 global/local versions on theory vs. Proof.context have been
  4405 discontinued; Attrib.syntax and Method.syntax have been adapted
  4406 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  4407 attributes, methods, etc.
  4408 
  4409 * Pure: several functions of signature "... -> theory -> theory * ..."
  4410 have been reoriented to "... -> theory -> ... * theory" in order to
  4411 allow natural usage in combination with the ||>, ||>>, |-> and
  4412 fold_map combinators.
  4413 
  4414 * Pure: official theorem names (closed derivations) and additional
  4415 comments (tags) are now strictly separate.  Name hints -- which are
  4416 maintained as tags -- may be attached any time without affecting the
  4417 derivation.
  4418 
  4419 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  4420 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  4421 achieve the old behaviour.
  4422 
  4423 * Pure: the "Goal" constant is now called "prop", supporting a
  4424 slightly more general idea of ``protecting'' meta-level rule
  4425 statements.
  4426 
  4427 * Pure: Logic.(un)varify only works in a global context, which is now
  4428 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  4429 Logic.legacy_(un)varify as temporary workaround.
  4430 
  4431 * Pure: structure Name provides scalable operations for generating
  4432 internal variable names, notably Name.variants etc.  This replaces
  4433 some popular functions from term.ML:
  4434 
  4435   Term.variant		->  Name.variant
  4436   Term.variantlist	->  Name.variant_list
  4437   Term.invent_names	->  Name.invent_list
  4438 
  4439 Note that low-level renaming rarely occurs in new code -- operations
  4440 from structure Variable are used instead (see below).
  4441 
  4442 * Pure: structure Variable provides fundamental operations for proper
  4443 treatment of fixed/schematic variables in a context.  For example,
  4444 Variable.import introduces fixes for schematics of given facts and
  4445 Variable.export reverses the effect (up to renaming) -- this replaces
  4446 various freeze_thaw operations.
  4447 
  4448 * Pure: structure Goal provides simple interfaces for
  4449 init/conclude/finish and tactical prove operations (replacing former
  4450 Tactic.prove).  Goal.prove is the canonical way to prove results
  4451 within a given context; Goal.prove_global is a degraded version for
  4452 theory level goals, including a global Drule.standard.  Note that
  4453 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  4454 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  4455 in a locale context).
  4456 
  4457 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  4458 and type checking (Syntax.check_term etc.), with common combinations
  4459 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  4460 which are considered legacy and await removal.
  4461 
  4462 * Pure/Syntax: generic interfaces for type unchecking
  4463 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  4464 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  4465 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  4466 available for convenience, but refer to the very same operations using
  4467 a mere theory instead of a full context.
  4468 
  4469 * Isar: simplified treatment of user-level errors, using exception
  4470 ERROR of string uniformly.  Function error now merely raises ERROR,
  4471 without any side effect on output channels.  The Isar toplevel takes
  4472 care of proper display of ERROR exceptions.  ML code may use plain
  4473 handle/can/try; cat_error may be used to concatenate errors like this:
  4474 
  4475   ... handle ERROR msg => cat_error msg "..."
  4476 
  4477 Toplevel ML code (run directly or through the Isar toplevel) may be
  4478 embedded into the Isar toplevel with exception display/debug like
  4479 this:
  4480 
  4481   Isar.toplevel (fn () => ...)
  4482 
  4483 INCOMPATIBILITY, removed special transform_error facilities, removed
  4484 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  4485 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  4486 -- use plain ERROR instead.
  4487 
  4488 * Isar: theory setup now has type (theory -> theory), instead of a
  4489 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  4490 
  4491 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  4492 ProofContext.debug/verbose flags.
  4493 
  4494 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  4495 theory before entering a proof state.  Transactions now always see a
  4496 quasi-functional intermediate checkpoint, both in interactive and
  4497 batch mode.
  4498 
  4499 * Isar: simplified interfaces for outer syntax.  Renamed
  4500 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  4501 OuterSyntax.add_parsers -- this functionality is now included in
  4502 OuterSyntax.command etc.  INCOMPATIBILITY.
  4503 
  4504 * Simplifier: the simpset of a running simplification process now
  4505 contains a proof context (cf. Simplifier.the_context), which is the
  4506 very context that the initial simpset has been retrieved from (by
  4507 simpset_of/local_simpset_of).  Consequently, all plug-in components
  4508 (solver, looper etc.) may depend on arbitrary proof data.
  4509 
  4510 * Simplifier.inherit_context inherits the proof context (plus the
  4511 local bounds) of the current simplification process; any simproc
  4512 etc. that calls the Simplifier recursively should do this!  Removed
  4513 former Simplifier.inherit_bounds, which is already included here --
  4514 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  4515 specify an explicit context using Simplifier.context/theory_context.
  4516 
  4517 * Simplifier/Classical Reasoner: more abstract interfaces
  4518 change_simpset/claset for modifying the simpset/claset reference of a
  4519 theory; raw versions simpset/claset_ref etc. have been discontinued --
  4520 INCOMPATIBILITY.
  4521 
  4522 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  4523 "Trueprop" etc.
  4524 
  4525 
  4526 *** System ***
  4527 
  4528 * settings: the default heap location within ISABELLE_HOME_USER now
  4529 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  4530 Isabelle installations.
  4531 
  4532 * isabelle-process: option -S (secure mode) disables some critical
  4533 operations, notably runtime compilation and evaluation of ML source
  4534 code.
  4535 
  4536 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  4537 
  4538 * Support for parallel execution, using native multicore support of
  4539 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  4540 independent theories, according to the given theory header
  4541 specifications. The maximum number of worker threads is specified via
  4542 usedir option -M or the "max-threads" setting in Proof General. A
  4543 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  4544 to 6 on a 8-core machine.  User-code needs to observe certain
  4545 guidelines for thread-safe programming, see appendix A in the Isar
  4546 Implementation manual.
  4547 
  4548 
  4549 
  4550 New in Isabelle2005 (October 2005)
  4551 ----------------------------------
  4552 
  4553 *** General ***
  4554 
  4555 * Theory headers: the new header syntax for Isar theories is
  4556 
  4557   theory <name>
  4558   imports <theory1> ... <theoryN>
  4559   uses <file1> ... <fileM>
  4560   begin
  4561 
  4562 where the 'uses' part is optional.  The previous syntax
  4563 
  4564   theory <name> = <theory1> + ... + <theoryN>:
  4565 
  4566 will disappear in the next release.  Use isatool fixheaders to convert
  4567 existing theory files.  Note that there is no change in ancient
  4568 non-Isar theories now, but these will disappear soon.
  4569 
  4570 * Theory loader: parent theories can now also be referred to via
  4571 relative and absolute paths.
  4572 
  4573 * Command 'find_theorems' searches for a list of criteria instead of a
  4574 list of constants. Known criteria are: intro, elim, dest, name:string,
  4575 simp:term, and any term. Criteria can be preceded by '-' to select
  4576 theorems that do not match. Intro, elim, dest select theorems that
  4577 match the current goal, name:s selects theorems whose fully qualified
  4578 name contain s, and simp:term selects all simplification rules whose
  4579 lhs match term.  Any other term is interpreted as pattern and selects
  4580 all theorems matching the pattern. Available in ProofGeneral under
  4581 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  4582 
  4583   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  4584 
  4585 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  4586 matching the current goal as introduction rule and not having "HOL."
  4587 in their name (i.e. not being defined in theory HOL).
  4588 
  4589 * Command 'thms_containing' has been discontinued in favour of
  4590 'find_theorems'; INCOMPATIBILITY.
  4591 
  4592 * Communication with Proof General is now 8bit clean, which means that
  4593 Unicode text in UTF-8 encoding may be used within theory texts (both
  4594 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4595 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4596 
  4597   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4598   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4599 
  4600 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4601 Classical Reasoner.  Typical big applications run around 2 times
  4602 faster.
  4603 
  4604 
  4605 *** Document preparation ***
  4606 
  4607 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4608 of raw sources.  Only those symbols that do not require additional
  4609 LaTeX packages (depending on comments in isabellesym.sty) are
  4610 displayed properly, everything else is left verbatim.  isatool display
  4611 and isatool print are used as front ends (these are subject to the
  4612 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4613 
  4614 * Command tags control specific markup of certain regions of text,
  4615 notably folding and hiding.  Predefined tags include "theory" (for
  4616 theory begin and end), "proof" for proof commands, and "ML" for
  4617 commands involving ML code; the additional tags "visible" and
  4618 "invisible" are unused by default.  Users may give explicit tag
  4619 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4620 interpretation of tags is determined by the LaTeX job during document
  4621 preparation: see option -V of isatool usedir, or options -n and -t of
  4622 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4623 \isadroptag.
  4624 
  4625 Several document versions may be produced at the same time via isatool
  4626 usedir (the generated index.html will link all of them).  Typical
  4627 specifications include ''-V document=theory,proof,ML'' to present
  4628 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4629 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4630 these parts without any formal replacement text.  The Isabelle site
  4631 default settings produce ''document'' and ''outline'' versions as
  4632 specified above.
  4633 
  4634 * Several new antiquotations:
  4635 
  4636   @{term_type term} prints a term with its type annotated;
  4637 
  4638   @{typeof term} prints the type of a term;
  4639 
  4640   @{const const} is the same as @{term const}, but checks that the
  4641   argument is a known logical constant;
  4642 
  4643   @{term_style style term} and @{thm_style style thm} print a term or
  4644   theorem applying a "style" to it
  4645 
  4646   @{ML text}
  4647 
  4648 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4649 definitions, equations, inequations etc., 'concl' printing only the
  4650 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4651 to print the specified premise.  TermStyle.add_style provides an ML
  4652 interface for introducing further styles.  See also the "LaTeX Sugar"
  4653 document practical applications.  The ML antiquotation prints
  4654 type-checked ML expressions verbatim.
  4655 
  4656 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4657 and 'text' support optional locale specification '(in loc)', which
  4658 specifies the default context for interpreting antiquotations.  For
  4659 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4660 
  4661 * Option 'locale=NAME' of antiquotations specifies an alternative
  4662 context interpreting the subsequent argument.  For example: @{thm
  4663 [locale=lattice] inf_assoc}.
  4664 
  4665 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4666 a proof context.
  4667 
  4668 * Proper output of antiquotations for theory commands involving a
  4669 proof context (such as 'locale' or 'theorem (in loc) ...').
  4670 
  4671 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4672 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4673 
  4674 * isatool usedir: new option -C (default true) controls whether option
  4675 -D should include a copy of the original document directory; -C false
  4676 prevents unwanted effects such as copying of administrative CVS data.
  4677 
  4678 
  4679 *** Pure ***
  4680 
  4681 * Considerably improved version of 'constdefs' command.  Now performs
  4682 automatic type-inference of declared constants; additional support for
  4683 local structure declarations (cf. locales and HOL records), see also
  4684 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4685 sequential dependencies of definitions within a single 'constdefs'
  4686 section; moreover, the declared name needs to be an identifier.  If
  4687 all fails, consider to fall back on 'consts' and 'defs' separately.
  4688 
  4689 * Improved indexed syntax and implicit structures.  First of all,
  4690 indexed syntax provides a notational device for subscripted
  4691 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4692 expressions.  Secondly, in a local context with structure
  4693 declarations, number indexes \<^sub>n or the empty index (default
  4694 number 1) refer to a certain fixed variable implicitly; option
  4695 show_structs controls printing of implicit structures.  Typical
  4696 applications of these concepts involve record types and locales.
  4697 
  4698 * New command 'no_syntax' removes grammar declarations (and
  4699 translations) resulting from the given syntax specification, which is
  4700 interpreted in the same manner as for the 'syntax' command.
  4701 
  4702 * 'Advanced' translation functions (parse_translation etc.) may depend
  4703 on the signature of the theory context being presently used for
  4704 parsing/printing, see also isar-ref manual.
  4705 
  4706 * Improved 'oracle' command provides a type-safe interface to turn an
  4707 ML expression of type theory -> T -> term into a primitive rule of
  4708 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4709 is already included here); see also FOL/ex/IffExample.thy;
  4710 INCOMPATIBILITY.
  4711 
  4712 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4713 before); "cI" is no longer bound, use "c.intro" instead.
  4714 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4715 axclasses vs. locales.
  4716 
  4717 * Improved internal renaming of symbolic identifiers -- attach primes
  4718 instead of base 26 numbers.
  4719 
  4720 * New flag show_question_marks controls printing of leading question
  4721 marks in schematic variable names.
  4722 
  4723 * In schematic variable names, *any* symbol following \<^isub> or
  4724 \<^isup> is now treated as part of the base name.  For example, the
  4725 following works without printing of awkward ".0" indexes:
  4726 
  4727   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4728     by simp
  4729 
  4730 * Inner syntax includes (*(*nested*) comments*).
  4731 
  4732 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4733 annotations as "(00...)".
  4734 
  4735 * Clear separation of logical types and nonterminals, where the latter
  4736 may only occur in 'syntax' specifications or type abbreviations.
  4737 Before that distinction was only partially implemented via type class
  4738 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4739 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4740 exotic syntax specifications may require further adaption
  4741 (e.g. Cube/Cube.thy).
  4742 
  4743 * Removed obsolete type class "logic", use the top sort {} instead.
  4744 Note that non-logical types should be declared as 'nonterminals'
  4745 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4746 specifications.
  4747 
  4748 * Attributes 'induct' and 'cases': type or set names may now be
  4749 locally fixed variables as well.
  4750 
  4751 * Simplifier: can now control the depth to which conditional rewriting
  4752 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4753 Limit.
  4754 
  4755 * Simplifier: simplification procedures may now take the current
  4756 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4757 interface), which is very useful for calling the Simplifier
  4758 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4759 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4760 low-level mk_simproc no longer applies Logic.varify internally, to
  4761 allow for use in a context of fixed variables.
  4762 
  4763 * thin_tac now works even if the assumption being deleted contains !!
  4764 or ==>.  More generally, erule now works even if the major premise of
  4765 the elimination rule contains !! or ==>.
  4766 
  4767 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4768 
  4769 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4770 from Pure, which contains all common declarations already.  Both
  4771 theories are defined via plain Isabelle/Isar .thy files.
  4772 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4773 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4774 use isatool fixcpure to adapt your theory and ML sources.
  4775 
  4776 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4777 selections of theorems in named facts via index ranges.
  4778 
  4779 * 'print_theorems': in theory mode, really print the difference
  4780 wrt. the last state (works for interactive theory development only),
  4781 in proof mode print all local facts (cf. 'print_facts');
  4782 
  4783 * 'hide': option '(open)' hides only base names.
  4784 
  4785 * More efficient treatment of intermediate checkpoints in interactive
  4786 theory development.
  4787 
  4788 * Code generator is now invoked via code_module (incremental code
  4789 generation) and code_library (modular code generation, ML structures
  4790 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4791 must be quoted when used as identifiers.
  4792 
  4793 * New 'value' command for reading, evaluating and printing terms using
  4794 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4795 quoted when used as identifier.
  4796 
  4797 
  4798 *** Locales ***
  4799 
  4800 * New commands for the interpretation of locale expressions in
  4801 theories (1), locales (2) and proof contexts (3).  These generate
  4802 proof obligations from the expression specification.  After the
  4803 obligations have been discharged, theorems of the expression are added
  4804 to the theory, target locale or proof context.  The synopsis of the
  4805 commands is a follows:
  4806 
  4807   (1) interpretation expr inst
  4808   (2) interpretation target < expr
  4809   (3) interpret expr inst
  4810 
  4811 Interpretation in theories and proof contexts require a parameter
  4812 instantiation of terms from the current context.  This is applied to
  4813 specifications and theorems of the interpreted expression.
  4814 Interpretation in locales only permits parameter renaming through the
  4815 locale expression.  Interpretation is smart in that interpretations
  4816 that are active already do not occur in proof obligations, neither are
  4817 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4818 inspect active interpretations of a particular locale.  For details,
  4819 see the Isar Reference manual.  Examples can be found in
  4820 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4821 
  4822 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4823 'interpret' instead.
  4824 
  4825 * New context element 'constrains' for adding type constraints to
  4826 parameters.
  4827 
  4828 * Context expressions: renaming of parameters with syntax
  4829 redeclaration.
  4830 
  4831 * Locale declaration: 'includes' disallowed.
  4832 
  4833 * Proper static binding of attribute syntax -- i.e. types / terms /
  4834 facts mentioned as arguments are always those of the locale definition
  4835 context, independently of the context of later invocations.  Moreover,
  4836 locale operations (renaming and type / term instantiation) are applied
  4837 to attribute arguments as expected.
  4838 
  4839 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4840 actual attributes; rare situations may require Attrib.attribute to
  4841 embed those attributes into Attrib.src that lack concrete syntax.
  4842 Attribute implementations need to cooperate properly with the static
  4843 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4844 Attrib.XXX_thm etc. already do the right thing without further
  4845 intervention.  Only unusual applications -- such as "where" or "of"
  4846 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4847 on the context and the facts involved -- may have to assign parsed
  4848 values to argument tokens explicitly.
  4849 
  4850 * Changed parameter management in theorem generation for long goal
  4851 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4852 theorem statement in rare situations.
  4853 
  4854 * Locale inspection command 'print_locale' omits notes elements.  Use
  4855 'print_locale!' to have them included in the output.
  4856 
  4857 
  4858 *** Provers ***
  4859 
  4860 * Provers/hypsubst.ML: improved version of the subst method, for
  4861 single-step rewriting: it now works in bound variable contexts. New is
  4862 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  4863 rewrite a different subterm than the original subst method, which is
  4864 still available as 'simplesubst'.
  4865 
  4866 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  4867 and quasi orders.
  4868 
  4869 * Provers/trancl.ML: new transitivity reasoner for transitive and
  4870 reflexive-transitive closure of relations.
  4871 
  4872 * Provers/blast.ML: new reference depth_limit to make blast's depth
  4873 limit (previously hard-coded with a value of 20) user-definable.
  4874 
  4875 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  4876 is peformed already.  Object-logics merely need to finish their
  4877 initial simpset configuration as before.  INCOMPATIBILITY.
  4878 
  4879 
  4880 *** HOL ***
  4881 
  4882 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  4883 
  4884   syntax (epsilon)
  4885     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  4886 
  4887 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  4888 and x-symbol; use option '-m epsilon' to get it actually printed.
  4889 Moreover, the mathematically important symbolic identifier \<epsilon>
  4890 becomes available as variable, constant etc.  INCOMPATIBILITY,
  4891 
  4892 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  4893 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  4894 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  4895 support corresponding Isar calculations.
  4896 
  4897 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  4898 instead of ":".
  4899 
  4900 * theory SetInterval: changed the syntax for open intervals:
  4901 
  4902   Old       New
  4903   {..n(}    {..<n}
  4904   {)n..}    {n<..}
  4905   {m..n(}   {m..<n}
  4906   {)m..n}   {m<..n}
  4907   {)m..n(}  {m<..<n}
  4908 
  4909 The old syntax is still supported but will disappear in the next
  4910 release.  For conversion use the following Emacs search and replace
  4911 patterns (these are not perfect but work quite well):
  4912 
  4913   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  4914   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  4915 
  4916 * Theory Commutative_Ring (in Library): method comm_ring for proving
  4917 equalities in commutative rings; method 'algebra' provides a generic
  4918 interface.
  4919 
  4920 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  4921 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  4922 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  4923 be a tuple pattern.
  4924 
  4925 Some new syntax forms are available:
  4926 
  4927   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  4928   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  4929   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  4930   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  4931 
  4932 The latter form "\<Sum>x < k. e" used to be based on a separate
  4933 function "Summation", which has been discontinued.
  4934 
  4935 * theory Finite_Set: in structured induction proofs, the insert case
  4936 is now 'case (insert x F)' instead of the old counterintuitive 'case
  4937 (insert F x)'.
  4938 
  4939 * The 'refute' command has been extended to support a much larger
  4940 fragment of HOL, including axiomatic type classes, constdefs and
  4941 typedefs, inductive datatypes and recursion.
  4942 
  4943 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  4944 Requires zChaff with proof generation to be installed.  See
  4945 HOL/ex/SAT_Examples.thy for examples.
  4946 
  4947 * Datatype induction via method 'induct' now preserves the name of the
  4948 induction variable. For example, when proving P(xs::'a list) by
  4949 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  4950 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  4951 in unstructured proof scripts.
  4952 
  4953 * Reworked implementation of records.  Improved scalability for
  4954 records with many fields, avoiding performance problems for type
  4955 inference. Records are no longer composed of nested field types, but
  4956 of nested extension types. Therefore the record type only grows linear
  4957 in the number of extensions and not in the number of fields.  The
  4958 top-level (users) view on records is preserved.  Potential
  4959 INCOMPATIBILITY only in strange cases, where the theory depends on the
  4960 old record representation. The type generated for a record is called
  4961 <record_name>_ext_type.
  4962 
  4963 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  4964 proofs triggered by a record definition or a simproc (if
  4965 quick_and_dirty is enabled).  Definitions of large records can take
  4966 quite long.
  4967 
  4968 New simproc record_upd_simproc for simplification of multiple record
  4969 updates enabled by default.  Moreover, trivial updates are also
  4970 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  4971 occasionally, since simplification is more powerful by default.
  4972 
  4973 * typedef: proper support for polymorphic sets, which contain extra
  4974 type-variables in the term.
  4975 
  4976 * Simplifier: automatically reasons about transitivity chains
  4977 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  4978 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  4979 old proofs break occasionally as simplification may now solve more
  4980 goals than previously.
  4981 
  4982 * Simplifier: converts x <= y into x = y if assumption y <= x is
  4983 present.  Works for all partial orders (class "order"), in particular
  4984 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  4985 just like y <= x.
  4986 
  4987 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  4988 bound variable or a constant then the let is unfolded.  Otherwise
  4989 first a is simplified to b, and then f b is simplified to g. If
  4990 possible we abstract b from g arriving at "let x = b in h x",
  4991 otherwise we unfold the let and arrive at g.  The simproc can be
  4992 enabled/disabled by the reference use_let_simproc.  Potential
  4993 INCOMPATIBILITY since simplification is more powerful by default.
  4994 
  4995 * Classical reasoning: the meson method now accepts theorems as arguments.
  4996 
  4997 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  4998 jobs to provide advice on the provability of subgoals.
  4999 
  5000 * Theory OrderedGroup and Ring_and_Field: various additions and
  5001 improvements to faciliate calculations involving equalities and
  5002 inequalities.
  5003 
  5004 The following theorems have been eliminated or modified
  5005 (INCOMPATIBILITY):
  5006 
  5007   abs_eq             now named abs_of_nonneg
  5008   abs_of_ge_0        now named abs_of_nonneg
  5009   abs_minus_eq       now named abs_of_nonpos
  5010   imp_abs_id         now named abs_of_nonneg
  5011   imp_abs_neg_id     now named abs_of_nonpos
  5012   mult_pos           now named mult_pos_pos
  5013   mult_pos_le        now named mult_nonneg_nonneg
  5014   mult_pos_neg_le    now named mult_nonneg_nonpos
  5015   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  5016   mult_neg           now named mult_neg_neg
  5017   mult_neg_le        now named mult_nonpos_nonpos
  5018 
  5019 * The following lemmas in Ring_and_Field have been added to the simplifier:
  5020      
  5021      zero_le_square
  5022      not_square_less_zero 
  5023 
  5024   The following lemmas have been deleted from Real/RealPow:
  5025   
  5026      realpow_zero_zero
  5027      realpow_two
  5028      realpow_less
  5029      zero_le_power
  5030      realpow_two_le
  5031      abs_realpow_two
  5032      realpow_two_abs     
  5033 
  5034 * Theory Parity: added rules for simplifying exponents.
  5035 
  5036 * Theory List:
  5037 
  5038 The following theorems have been eliminated or modified
  5039 (INCOMPATIBILITY):
  5040 
  5041   list_all_Nil       now named list_all.simps(1)
  5042   list_all_Cons      now named list_all.simps(2)
  5043   list_all_conv      now named list_all_iff
  5044   set_mem_eq         now named mem_iff
  5045 
  5046 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  5047 asymptotic "big O" calculations.  See the notes in BigO.thy.
  5048 
  5049 
  5050 *** HOL-Complex ***
  5051 
  5052 * Theory RealDef: better support for embedding natural numbers and
  5053 integers in the reals.
  5054 
  5055 The following theorems have been eliminated or modified
  5056 (INCOMPATIBILITY):
  5057 
  5058   exp_ge_add_one_self  now requires no hypotheses
  5059   real_of_int_add      reversed direction of equality (use [symmetric])
  5060   real_of_int_minus    reversed direction of equality (use [symmetric])
  5061   real_of_int_diff     reversed direction of equality (use [symmetric])
  5062   real_of_int_mult     reversed direction of equality (use [symmetric])
  5063 
  5064 * Theory RComplete: expanded support for floor and ceiling functions.
  5065 
  5066 * Theory Ln is new, with properties of the natural logarithm
  5067 
  5068 * Hyperreal: There is a new type constructor "star" for making
  5069 nonstandard types.  The old type names are now type synonyms:
  5070 
  5071   hypreal = real star
  5072   hypnat = nat star
  5073   hcomplex = complex star
  5074 
  5075 * Hyperreal: Many groups of similarly-defined constants have been
  5076 replaced by polymorphic versions (INCOMPATIBILITY):
  5077 
  5078   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  5079 
  5080   starset      <-- starsetNat, starsetC
  5081   *s*          <-- *sNat*, *sc*
  5082   starset_n    <-- starsetNat_n, starsetC_n
  5083   *sn*         <-- *sNatn*, *scn*
  5084   InternalSets <-- InternalNatSets, InternalCSets
  5085 
  5086   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  5087   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  5088   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  5089   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  5090   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  5091 
  5092 * Hyperreal: Many type-specific theorems have been removed in favor of
  5093 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  5094 
  5095   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  5096   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  5097   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  5098   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  5099   right_minus <-- hypreal_add_minus
  5100   left_minus <-- {hypreal,hcomplex}_add_minus_left
  5101   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  5102   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  5103   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  5104   mult_1_right <-- hcomplex_mult_one_right
  5105   mult_zero_left <-- hcomplex_mult_zero_left
  5106   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  5107   right_distrib <-- hypnat_add_mult_distrib2
  5108   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  5109   right_inverse <-- hypreal_mult_inverse
  5110   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  5111   order_refl <-- {hypreal,hypnat}_le_refl
  5112   order_trans <-- {hypreal,hypnat}_le_trans
  5113   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  5114   order_less_le <-- {hypreal,hypnat}_less_le
  5115   linorder_linear <-- {hypreal,hypnat}_le_linear
  5116   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  5117   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  5118   add_nonneg_nonneg <-- hypreal_le_add_order
  5119 
  5120 * Hyperreal: Separate theorems having to do with type-specific
  5121 versions of constants have been merged into theorems that apply to the
  5122 new polymorphic constants (INCOMPATIBILITY):
  5123 
  5124   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  5125   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  5126   STAR_Un <-- {STAR,NatStar,STARC}_Un
  5127   STAR_Int <-- {STAR,NatStar,STARC}_Int
  5128   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  5129   STAR_subset <-- {STAR,NatStar,STARC}_subset
  5130   STAR_mem <-- {STAR,NatStar,STARC}_mem
  5131   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  5132   STAR_diff <-- {STAR,STARC}_diff
  5133   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  5134     STARC_hcomplex_of_complex}_image_subset
  5135   starset_n_Un <-- starset{Nat,C}_n_Un
  5136   starset_n_Int <-- starset{Nat,C}_n_Int
  5137   starset_n_Compl <-- starset{Nat,C}_n_Compl
  5138   starset_n_diff <-- starset{Nat,C}_n_diff
  5139   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  5140   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  5141   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  5142   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  5143   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  5144   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  5145   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  5146   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  5147   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  5148   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  5149   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  5150   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  5151   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  5152   starfun_diff <-- starfun{C,RC,CR}_diff
  5153   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  5154   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  5155   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  5156   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  5157   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  5158   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  5159   starfun_Id <-- starfunC_Id
  5160   starfun_approx <-- starfun{Nat,CR}_approx
  5161   starfun_capprox <-- starfun{C,RC}_capprox
  5162   starfun_abs <-- starfunNat_rabs
  5163   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  5164   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  5165   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  5166   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  5167   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  5168   starfun_add_approx <-- starfunCR_add_approx
  5169   starfun_inverse_inverse <-- starfunC_inverse_inverse
  5170   starfun_divide <-- starfun{C,CR,RC}_divide
  5171   starfun_n <-- starfun{Nat,C}_n
  5172   starfun_n_mult <-- starfun{Nat,C}_n_mult
  5173   starfun_n_add <-- starfun{Nat,C}_n_add
  5174   starfun_n_add_minus <-- starfunNat_n_add_minus
  5175   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  5176   starfun_n_minus <-- starfun{Nat,C}_n_minus
  5177   starfun_n_eq <-- starfun{Nat,C}_n_eq
  5178 
  5179   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  5180   star_n_minus <-- {hypreal,hcomplex}_minus
  5181   star_n_diff <-- {hypreal,hcomplex}_diff
  5182   star_n_mult <-- {hypreal,hcomplex}_mult
  5183   star_n_inverse <-- {hypreal,hcomplex}_inverse
  5184   star_n_le <-- {hypreal,hypnat}_le
  5185   star_n_less <-- {hypreal,hypnat}_less
  5186   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  5187   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  5188   star_n_abs <-- hypreal_hrabs
  5189   star_n_divide <-- hcomplex_divide
  5190 
  5191   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  5192   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  5193   star_of_diff <-- hypreal_of_real_diff
  5194   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  5195   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  5196   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  5197   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  5198   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  5199   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  5200   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  5201   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  5202   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  5203   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  5204   star_of_number_of <-- {hypreal,hcomplex}_number_of
  5205   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  5206   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  5207   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  5208   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  5209   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  5210   star_of_power <-- hypreal_of_real_power
  5211   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  5212 
  5213 * Hyperreal: new method "transfer" that implements the transfer
  5214 principle of nonstandard analysis. With a subgoal that mentions
  5215 nonstandard types like "'a star", the command "apply transfer"
  5216 replaces it with an equivalent one that mentions only standard types.
  5217 To be successful, all free variables must have standard types; non-
  5218 standard variables must have explicit universal quantifiers.
  5219 
  5220 * Hyperreal: A theory of Taylor series.
  5221 
  5222 
  5223 *** HOLCF ***
  5224 
  5225 * Discontinued special version of 'constdefs' (which used to support
  5226 continuous functions) in favor of the general Pure one with full
  5227 type-inference.
  5228 
  5229 * New simplification procedure for solving continuity conditions; it
  5230 is much faster on terms with many nested lambda abstractions (cubic
  5231 instead of exponential time).
  5232 
  5233 * New syntax for domain package: selector names are now optional.
  5234 Parentheses should be omitted unless argument is lazy, for example:
  5235 
  5236   domain 'a stream = cons "'a" (lazy "'a stream")
  5237 
  5238 * New command 'fixrec' for defining recursive functions with pattern
  5239 matching; defining multiple functions with mutual recursion is also
  5240 supported.  Patterns may include the constants cpair, spair, up, sinl,
  5241 sinr, or any data constructor defined by the domain package. The given
  5242 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  5243 syntax and examples.
  5244 
  5245 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  5246 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  5247 but the proof obligation additionally includes an admissibility
  5248 requirement. The packages generate instances of class cpo or pcpo,
  5249 with continuity and strictness theorems for Rep and Abs.
  5250 
  5251 * HOLCF: Many theorems have been renamed according to a more standard naming
  5252 scheme (INCOMPATIBILITY):
  5253 
  5254   foo_inject:  "foo$x = foo$y ==> x = y"
  5255   foo_eq:      "(foo$x = foo$y) = (x = y)"
  5256   foo_less:    "(foo$x << foo$y) = (x << y)"
  5257   foo_strict:  "foo$UU = UU"
  5258   foo_defined: "... ==> foo$x ~= UU"
  5259   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  5260 
  5261 
  5262 *** ZF ***
  5263 
  5264 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  5265 including the First Isomorphism Theorem (on quotienting by the kernel
  5266 of a homomorphism).
  5267 
  5268 * ZF/Simplifier: install second copy of type solver that actually
  5269 makes use of TC rules declared to Isar proof contexts (or locales);
  5270 the old version is still required for ML proof scripts.
  5271 
  5272 
  5273 *** Cube ***
  5274 
  5275 * Converted to Isar theory format; use locales instead of axiomatic
  5276 theories.
  5277 
  5278 
  5279 *** ML ***
  5280 
  5281 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  5282 for ||>, ||>>, |>>,
  5283 
  5284 * Pure/library.ML no longer defines its own option datatype, but uses
  5285 that of the SML basis, which has constructors NONE and SOME instead of
  5286 None and Some, as well as exception Option.Option instead of OPTION.
  5287 The functions the, if_none, is_some, is_none have been adapted
  5288 accordingly, while Option.map replaces apsome.
  5289 
  5290 * Pure/library.ML: the exception LIST has been given up in favour of
  5291 the standard exceptions Empty and Subscript, as well as
  5292 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  5293 superceded by the standard hd and tl functions etc.
  5294 
  5295 A number of basic list functions are no longer exported to the ML
  5296 toplevel, as they are variants of predefined functions.  The following
  5297 suggests how one can translate existing code:
  5298 
  5299     rev_append xs ys = List.revAppend (xs, ys)
  5300     nth_elem (i, xs) = List.nth (xs, i)
  5301     last_elem xs = List.last xs
  5302     flat xss = List.concat xss
  5303     seq fs = List.app fs
  5304     partition P xs = List.partition P xs
  5305     mapfilter f xs = List.mapPartial f xs
  5306 
  5307 * Pure/library.ML: several combinators for linear functional
  5308 transformations, notably reverse application and composition:
  5309 
  5310   x |> f                f #> g
  5311   (x, y) |-> f          f #-> g
  5312 
  5313 * Pure/library.ML: introduced/changed precedence of infix operators:
  5314 
  5315   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  5316   infix 2 ?;
  5317   infix 3 o oo ooo oooo;
  5318   infix 4 ~~ upto downto;
  5319 
  5320 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  5321 infix operators.
  5322 
  5323 * Pure/library.ML: natural list combinators fold, fold_rev, and
  5324 fold_map support linear functional transformations and nesting.  For
  5325 example:
  5326 
  5327   fold f [x1, ..., xN] y =
  5328     y |> f x1 |> ... |> f xN
  5329 
  5330   (fold o fold) f [xs1, ..., xsN] y =
  5331     y |> fold f xs1 |> ... |> fold f xsN
  5332 
  5333   fold f [x1, ..., xN] =
  5334     f x1 #> ... #> f xN
  5335 
  5336   (fold o fold) f [xs1, ..., xsN] =
  5337     fold f xs1 #> ... #> fold f xsN
  5338 
  5339 * Pure/library.ML: the following selectors on type 'a option are
  5340 available:
  5341 
  5342   the:               'a option -> 'a  (*partial*)
  5343   these:             'a option -> 'a  where 'a = 'b list
  5344   the_default: 'a -> 'a option -> 'a
  5345   the_list:          'a option -> 'a list
  5346 
  5347 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5348 basic operations for association lists, following natural argument
  5349 order; moreover the explicit equality predicate passed here avoids
  5350 potentially expensive polymorphic runtime equality checks.
  5351 The old functions may be expressed as follows:
  5352 
  5353   assoc = uncurry (AList.lookup (op =))
  5354   assocs = these oo AList.lookup (op =)
  5355   overwrite = uncurry (AList.update (op =)) o swap
  5356 
  5357 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5358 
  5359   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  5360   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  5361 
  5362 replacing make_keylist and keyfilter (occassionally used)
  5363 Naive rewrites:
  5364 
  5365   make_keylist = AList.make
  5366   keyfilter = AList.find (op =)
  5367 
  5368 * eq_fst and eq_snd now take explicit equality parameter, thus
  5369   avoiding eqtypes. Naive rewrites:
  5370 
  5371     eq_fst = eq_fst (op =)
  5372     eq_snd = eq_snd (op =)
  5373 
  5374 * Removed deprecated apl and apr (rarely used).
  5375   Naive rewrites:
  5376 
  5377     apl (n, op) =>>= curry op n
  5378     apr (op, m) =>>= fn n => op (n, m)
  5379 
  5380 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  5381 provides a reasonably efficient light-weight implementation of sets as
  5382 lists.
  5383 
  5384 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  5385 few new operations; existing lookup and update are now curried to
  5386 follow natural argument order (for use with fold etc.);
  5387 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  5388 
  5389 * Pure/General: output via the Isabelle channels of
  5390 writeln/warning/error etc. is now passed through Output.output, with a
  5391 hook for arbitrary transformations depending on the print_mode
  5392 (cf. Output.add_mode -- the first active mode that provides a output
  5393 function wins).  Already formatted output may be embedded into further
  5394 text via Output.raw; the result of Pretty.string_of/str_of and derived
  5395 functions (string_of_term/cterm/thm etc.) is already marked raw to
  5396 accommodate easy composition of diagnostic messages etc.  Programmers
  5397 rarely need to care about Output.output or Output.raw at all, with
  5398 some notable exceptions: Output.output is required when bypassing the
  5399 standard channels (writeln etc.), or in token translations to produce
  5400 properly formatted results; Output.raw is required when capturing
  5401 already output material that will eventually be presented to the user
  5402 a second time.  For the default print mode, both Output.output and
  5403 Output.raw have no effect.
  5404 
  5405 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  5406 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  5407 cumulative results are displayed at the end of a batch session.
  5408 
  5409 * Pure/General: File.sysify_path and File.quote_sysify path have been
  5410 replaced by File.platform_path and File.shell_path (with appropriate
  5411 hooks).  This provides a clean interface for unusual systems where the
  5412 internal and external process view of file names are different.
  5413 
  5414 * Pure: more efficient orders for basic syntactic entities: added
  5415 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  5416 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  5417 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  5418 orders now -- potential INCOMPATIBILITY for code that depends on a
  5419 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  5420 Library.sort_strings on result).
  5421 
  5422 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  5423 fold_types traverse types/terms from left to right, observing natural
  5424 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  5425 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  5426 
  5427 * Pure: name spaces have been refined, with significant changes of the
  5428 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  5429 to extern(_table).  The plain name entry path is superceded by a
  5430 general 'naming' context, which also includes the 'policy' to produce
  5431 a fully qualified name and external accesses of a fully qualified
  5432 name; NameSpace.extend is superceded by context dependent
  5433 Sign.declare_name.  Several theory and proof context operations modify
  5434 the naming context.  Especially note Theory.restore_naming and
  5435 ProofContext.restore_naming to get back to a sane state; note that
  5436 Theory.add_path is no longer sufficient to recover from
  5437 Theory.absolute_path in particular.
  5438 
  5439 * Pure: new flags short_names (default false) and unique_names
  5440 (default true) for controlling output of qualified names.  If
  5441 short_names is set, names are printed unqualified.  If unique_names is
  5442 reset, the name prefix is reduced to the minimum required to achieve
  5443 the original result when interning again, even if there is an overlap
  5444 with earlier declarations.
  5445 
  5446 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  5447 now 'extend', and 'merge' gets an additional Pretty.pp argument
  5448 (useful for printing error messages).  INCOMPATIBILITY.
  5449 
  5450 * Pure: major reorganization of the theory context.  Type Sign.sg and
  5451 Theory.theory are now identified, referring to the universal
  5452 Context.theory (see Pure/context.ML).  Actual signature and theory
  5453 content is managed as theory data.  The old code and interfaces were
  5454 spread over many files and structures; the new arrangement introduces
  5455 considerable INCOMPATIBILITY to gain more clarity:
  5456 
  5457   Context -- theory management operations (name, identity, inclusion,
  5458     parents, ancestors, merge, etc.), plus generic theory data;
  5459 
  5460   Sign -- logical signature and syntax operations (declaring consts,
  5461     types, etc.), plus certify/read for common entities;
  5462 
  5463   Theory -- logical theory operations (stating axioms, definitions,
  5464     oracles), plus a copy of logical signature operations (consts,
  5465     types, etc.); also a few basic management operations (Theory.copy,
  5466     Theory.merge, etc.)
  5467 
  5468 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  5469 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  5470 for convenience -- they merely return the theory.
  5471 
  5472 * Pure: type Type.tsig is superceded by theory in most interfaces.
  5473 
  5474 * Pure: the Isar proof context type is already defined early in Pure
  5475 as Context.proof (note that ProofContext.context and Proof.context are
  5476 aliases, where the latter is the preferred name).  This enables other
  5477 Isabelle components to refer to that type even before Isar is present.
  5478 
  5479 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  5480 typeK, constK, axiomK, oracleK), but provide explicit operations for
  5481 any of these kinds.  For example, Sign.intern typeK is now
  5482 Sign.intern_type, Theory.hide_space Sign.typeK is now
  5483 Theory.hide_types.  Also note that former
  5484 Theory.hide_classes/types/consts are now
  5485 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  5486 internalize their arguments!  INCOMPATIBILITY.
  5487 
  5488 * Pure: get_thm interface (of PureThy and ProofContext) expects
  5489 datatype thmref (with constructors Name and NameSelection) instead of
  5490 plain string -- INCOMPATIBILITY;
  5491 
  5492 * Pure: cases produced by proof methods specify options, where NONE
  5493 means to remove case bindings -- INCOMPATIBILITY in
  5494 (RAW_)METHOD_CASES.
  5495 
  5496 * Pure: the following operations retrieve axioms or theorems from a
  5497 theory node or theory hierarchy, respectively:
  5498 
  5499   Theory.axioms_of: theory -> (string * term) list
  5500   Theory.all_axioms_of: theory -> (string * term) list
  5501   PureThy.thms_of: theory -> (string * thm) list
  5502   PureThy.all_thms_of: theory -> (string * thm) list
  5503 
  5504 * Pure: print_tac now outputs the goal through the trace channel.
  5505 
  5506 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  5507 Reference Toplevel.debug (default false) controls detailed printing
  5508 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  5509 controls execution profiling -- set to 1 for time and 2 for space
  5510 (both increase the runtime).
  5511 
  5512 * Isar session: The initial use of ROOT.ML is now always timed,
  5513 i.e. the log will show the actual process times, in contrast to the
  5514 elapsed wall-clock time that the outer shell wrapper produces.
  5515 
  5516 * Simplifier: improved handling of bound variables (nameless
  5517 representation, avoid allocating new strings).  Simprocs that invoke
  5518 the Simplifier recursively should use Simplifier.inherit_bounds to
  5519 avoid local name clashes.  Failure to do so produces warnings
  5520 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  5521 for further details.
  5522 
  5523 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  5524 bindings for all theorems stored within a given theory; this may help
  5525 in porting non-Isar theories to Isar ones, while keeping ML proof
  5526 scripts for the time being.
  5527 
  5528 * ML operator HTML.with_charset specifies the charset begin used for
  5529 generated HTML files.  For example:
  5530 
  5531   HTML.with_charset "utf-8" use_thy "Hebrew";
  5532   HTML.with_charset "utf-8" use_thy "Chinese";
  5533 
  5534 
  5535 *** System ***
  5536 
  5537 * Allow symlinks to all proper Isabelle executables (Isabelle,
  5538 isabelle, isatool etc.).
  5539 
  5540 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  5541 isatool doc, isatool mkdir, display_drafts etc.).
  5542 
  5543 * isatool usedir: option -f allows specification of the ML file to be
  5544 used by Isabelle; default is ROOT.ML.
  5545 
  5546 * New isatool version outputs the version identifier of the Isabelle
  5547 distribution being used.
  5548 
  5549 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  5550 (containing Boolean satisfiability problems) into Isabelle/HOL
  5551 theories.
  5552 
  5553 
  5554 
  5555 New in Isabelle2004 (April 2004)
  5556 --------------------------------
  5557 
  5558 *** General ***
  5559 
  5560 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  5561   Replaces linorder.ML.
  5562 
  5563 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  5564   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  5565   (\<a>...\<z>), are now considered normal letters, and can therefore
  5566   be used anywhere where an ASCII letter (a...zA...Z) has until
  5567   now. COMPATIBILITY: This obviously changes the parsing of some
  5568   terms, especially where a symbol has been used as a binder, say
  5569   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  5570   as an identifier.  Fix it by inserting a space around former
  5571   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  5572   existing theory and ML files.
  5573 
  5574 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  5575 
  5576 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  5577   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  5578   a normal (but invisible) letter. For multiple letter subscripts repeat
  5579   \<^isub> like this: x\<^isub>1\<^isub>2.
  5580 
  5581 * Pure: There are now sub-/superscripts that can span more than one
  5582   character. Text between \<^bsub> and \<^esub> is set in subscript in
  5583   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  5584   superscript. The new control characters are not identifier parts.
  5585 
  5586 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5587   content of "..." to the latex file instead of \isacntrl... . The "..."
  5588   may consist of any printable characters excluding the end bracket >.
  5589 
  5590 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5591   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5592   declare constants "final", which prevents their being given a definition
  5593   later.  It is useful for constants whose behaviour is fixed axiomatically
  5594   rather than definitionally, such as the meta-logic connectives.
  5595 
  5596 * Pure: 'instance' now handles general arities with general sorts
  5597   (i.e. intersections of classes),
  5598 
  5599 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5600   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5601   It can be changed to alter the colors/layout of generated pages.
  5602 
  5603 
  5604 *** Isar ***
  5605 
  5606 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5607   cut_tac, subgoal_tac and thin_tac:
  5608   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5609     locales are no longer forced to write Isar proof scripts.
  5610     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5611     emulations.
  5612   - INCOMPATIBILITY: names of variables to be instantiated may no
  5613     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5614     This is consistent with the instantiation attribute "where".
  5615 
  5616 * Attributes "where" and "of":
  5617   - Now take type variables of instantiated theorem into account when reading
  5618     the instantiation string.  This fixes a bug that caused instantiated
  5619     theorems to have too special types in some circumstances.
  5620   - "where" permits explicit instantiations of type variables.
  5621 
  5622 * Calculation commands "moreover" and "also" no longer interfere with
  5623   current facts ("this"), admitting arbitrary combinations with "then"
  5624   and derived forms.
  5625 
  5626 * Locales:
  5627   - Goal statements involving the context element "includes" no longer
  5628     generate theorems with internal delta predicates (those ending on
  5629     "_axioms") in the premise.
  5630     Resolve particular premise with <locale>.intro to obtain old form.
  5631   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5632     specification and "includes" elements in goal statement.
  5633   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5634     [intro?] and [elim?] (respectively) by default.
  5635   - Experimental command for instantiation of locales in proof contexts:
  5636         instantiate <label>[<attrs>]: <loc>
  5637     Instantiates locale <loc> and adds all its theorems to the current context
  5638     taking into account their attributes.  Label and attrs are optional
  5639     modifiers, like in theorem declarations.  If present, names of
  5640     instantiated theorems are qualified with <label>, and the attributes
  5641     <attrs> are applied after any attributes these theorems might have already.
  5642       If the locale has assumptions, a chained fact of the form
  5643     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5644     are derived.  The command does not support old-style locales declared
  5645     with "locale (open)".
  5646       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5647 
  5648 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5649   (Isar) contexts.
  5650 
  5651 
  5652 *** HOL ***
  5653 
  5654 * Proof import: new image HOL4 contains the imported library from
  5655   the HOL4 system with about 2500 theorems. It is imported by
  5656   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5657   can be used like any other Isabelle image.  See
  5658   HOL/Import/HOL/README for more information.
  5659 
  5660 * Simplifier:
  5661   - Much improved handling of linear and partial orders.
  5662     Reasoners for linear and partial orders are set up for type classes
  5663     "linorder" and "order" respectively, and are added to the default simpset
  5664     as solvers.  This means that the simplifier can build transitivity chains
  5665     to solve goals from the assumptions.
  5666   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5667     of blast or auto after simplification become unnecessary because the goal
  5668     is solved by simplification already.
  5669 
  5670 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5671     all proved in axiomatic type classes for semirings, rings and fields.
  5672 
  5673 * Numerics:
  5674   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5675     now formalized using the Ring_and_Field theory mentioned above.
  5676   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5677     than before, because now they are set up once in a generic manner.
  5678   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5679     Look for the general versions in Ring_and_Field (and Power if they concern
  5680     exponentiation).
  5681 
  5682 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5683 
  5684 * Records:
  5685   - Record types are now by default printed with their type abbreviation
  5686     instead of the list of all field types. This can be configured via
  5687     the reference "print_record_type_abbr".
  5688   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5689     (not enabled by default).
  5690   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5691     EX x. x = sel r to True (not enabled by default).
  5692   - Tactic "record_split_simp_tac" to split and simplify records added.
  5693 
  5694 * 'specification' command added, allowing for definition by
  5695   specification.  There is also an 'ax_specification' command that
  5696   introduces the new constants axiomatically.
  5697 
  5698 * arith(_tac) is now able to generate counterexamples for reals as well.
  5699 
  5700 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5701 
  5702 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5703   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5704 
  5705 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5706   matrix theory to linear programming.
  5707 
  5708 * Unions and Intersections:
  5709   The latex output syntax of UN and INT has been changed
  5710   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5711   i.e. the index formulae has become a subscript.
  5712   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5713 
  5714 * Unions and Intersections over Intervals:
  5715   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5716   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5717   like in normal math, and corresponding versions for < and for intersection.
  5718 
  5719 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5720   lexicographic dictonary ordering has been added as "lexord".
  5721 
  5722 * ML: the legacy theory structures Int and List have been removed. They had
  5723   conflicted with ML Basis Library structures having the same names.
  5724 
  5725 * 'refute' command added to search for (finite) countermodels.  Only works
  5726   for a fragment of HOL.  The installation of an external SAT solver is
  5727   highly recommended.  See "HOL/Refute.thy" for details.
  5728 
  5729 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5730   formulae under an assignment of free variables to random values.
  5731   In contrast to 'refute', it can deal with inductive datatypes,
  5732   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5733   for examples.
  5734 
  5735 
  5736 *** HOLCF ***
  5737 
  5738 * Streams now come with concatenation and are part of the HOLCF image
  5739 
  5740 
  5741 
  5742 New in Isabelle2003 (May 2003)
  5743 ------------------------------
  5744 
  5745 *** General ***
  5746 
  5747 * Provers/simplifier:
  5748 
  5749   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5750     Assumptions are now subject to complete mutual simplification,
  5751     not just from left to right. The simplifier now preserves
  5752     the order of assumptions.
  5753 
  5754     Potential INCOMPATIBILITY:
  5755 
  5756     -- simp sometimes diverges where the old version did
  5757        not, e.g. invoking simp on the goal
  5758 
  5759         [| P (f x); y = x; f x = f y |] ==> Q
  5760 
  5761        now gives rise to the infinite reduction sequence
  5762 
  5763         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5764 
  5765        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5766        kind of problem.
  5767 
  5768     -- Tactics combining classical reasoner and simplification (such as auto)
  5769        are also affected by this change, because many of them rely on
  5770        simp. They may sometimes diverge as well or yield a different numbers
  5771        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5772        in case of problems. Sometimes subsequent calls to the classical
  5773        reasoner will fail because a preceeding call to the simplifier too
  5774        eagerly simplified the goal, e.g. deleted redundant premises.
  5775 
  5776   - The simplifier trace now shows the names of the applied rewrite rules
  5777 
  5778   - You can limit the number of recursive invocations of the simplifier
  5779     during conditional rewriting (where the simplifie tries to solve the
  5780     conditions before applying the rewrite rule):
  5781     ML "simp_depth_limit := n"
  5782     where n is an integer. Thus you can force termination where previously
  5783     the simplifier would diverge.
  5784 
  5785   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5786 
  5787   - No longer aborts on failed congruence proof.  Instead, the
  5788     congruence is ignored.
  5789 
  5790 * Pure: New generic framework for extracting programs from constructive
  5791   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5792   as HOL/Extraction for some case studies.
  5793 
  5794 * Pure: The main goal of the proof state is no longer shown by default, only
  5795 the subgoals. This behaviour is controlled by a new flag.
  5796    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5797 (ML: Proof.show_main_goal).
  5798 
  5799 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5800 rules whose conclusion matches subgoal 1:
  5801       PG menu: Isabelle/Isar -> Show me -> matching rules
  5802 The rules are ordered by how closely they match the subgoal.
  5803 In particular, rules that solve a subgoal outright are displayed first
  5804 (or rather last, the way they are printed).
  5805 (ML: ProofGeneral.print_intros())
  5806 
  5807 * Pure: New flag trace_unify_fail causes unification to print
  5808 diagnostic information (PG: in trace buffer) when it fails. This is
  5809 useful for figuring out why single step proofs like rule, erule or
  5810 assumption failed.
  5811 
  5812 * Pure: Locale specifications now produce predicate definitions
  5813 according to the body of text (covering assumptions modulo local
  5814 definitions); predicate "loc_axioms" covers newly introduced text,
  5815 while "loc" is cumulative wrt. all included locale expressions; the
  5816 latter view is presented only on export into the global theory
  5817 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5818 on the old view without predicates;
  5819 
  5820 * Pure: predefined locales "var" and "struct" are useful for sharing
  5821 parameters (as in CASL, for example); just specify something like
  5822 ``var x + var y + struct M'' as import;
  5823 
  5824 * Pure: improved thms_containing: proper indexing of facts instead of
  5825 raw theorems; check validity of results wrt. current name space;
  5826 include local facts of proof configuration (also covers active
  5827 locales), cover fixed variables in index; may use "_" in term
  5828 specification; an optional limit for the number of printed facts may
  5829 be given (the default is 40);
  5830 
  5831 * Pure: disallow duplicate fact bindings within new-style theory files
  5832 (batch-mode only);
  5833 
  5834 * Provers: improved induct method: assumptions introduced by case
  5835 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5836 the goal statement); "foo" still refers to all facts collectively;
  5837 
  5838 * Provers: the function blast.overloaded has been removed: all constants
  5839 are regarded as potentially overloaded, which improves robustness in exchange
  5840 for slight decrease in efficiency;
  5841 
  5842 * Provers/linorder: New generic prover for transitivity reasoning over
  5843 linear orders.  Note: this prover is not efficient!
  5844 
  5845 * Isar: preview of problems to finish 'show' now produce an error
  5846 rather than just a warning (in interactive mode);
  5847 
  5848 
  5849 *** HOL ***
  5850 
  5851 * arith(_tac)
  5852 
  5853  - Produces a counter example if it cannot prove a goal.
  5854    Note that the counter example may be spurious if the goal is not a formula
  5855    of quantifier-free linear arithmetic.
  5856    In ProofGeneral the counter example appears in the trace buffer.
  5857 
  5858  - Knows about div k and mod k where k is a numeral of type nat or int.
  5859 
  5860  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  5861    linear arithmetic fails. This takes account of quantifiers and divisibility.
  5862    Presburger arithmetic can also be called explicitly via presburger(_tac).
  5863 
  5864 * simp's arithmetic capabilities have been enhanced a bit: it now
  5865 takes ~= in premises into account (by performing a case split);
  5866 
  5867 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  5868 are distributed over a sum of terms;
  5869 
  5870 * New tactic "trans_tac" and method "trans" instantiate
  5871 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  5872 "<=", "<" and "=").
  5873 
  5874 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  5875 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  5876 
  5877 * 'typedef' command has new option "open" to suppress the set
  5878 definition;
  5879 
  5880 * functions Min and Max on finite sets have been introduced (theory
  5881 Finite_Set);
  5882 
  5883 * attribute [symmetric] now works for relations as well; it turns
  5884 (x,y) : R^-1 into (y,x) : R, and vice versa;
  5885 
  5886 * induct over a !!-quantified statement (say !!x1..xn):
  5887   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  5888 
  5889 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  5890 %x. None. Warning: empty_def now refers to the previously hidden definition
  5891 of the empty set.
  5892 
  5893 * Algebra: formalization of classical algebra.  Intended as base for
  5894 any algebraic development in Isabelle.  Currently covers group theory
  5895 (up to Sylow's theorem) and ring theory (Universal Property of
  5896 Univariate Polynomials).  Contributions welcome;
  5897 
  5898 * GroupTheory: deleted, since its material has been moved to Algebra;
  5899 
  5900 * Complex: new directory of the complex numbers with numeric constants,
  5901 nonstandard complex numbers, and some complex analysis, standard and
  5902 nonstandard (Jacques Fleuriot);
  5903 
  5904 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  5905 
  5906 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  5907 Fleuriot);
  5908 
  5909 * Real/HahnBanach: updated and adapted to locales;
  5910 
  5911 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  5912 Gray and Kramer);
  5913 
  5914 * UNITY: added the Meier-Sanders theory of progress sets;
  5915 
  5916 * MicroJava: bytecode verifier and lightweight bytecode verifier
  5917 as abstract algorithms, instantiated to the JVM;
  5918 
  5919 * Bali: Java source language formalization. Type system, operational
  5920 semantics, axiomatic semantics. Supported language features:
  5921 classes, interfaces, objects,virtual methods, static methods,
  5922 static/instance fields, arrays, access modifiers, definite
  5923 assignment, exceptions.
  5924 
  5925 
  5926 *** ZF ***
  5927 
  5928 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  5929 universe, etc.);
  5930 
  5931 * Main ZF: virtually all theories converted to new-style format;
  5932 
  5933 
  5934 *** ML ***
  5935 
  5936 * Pure: Tactic.prove provides sane interface for internal proofs;
  5937 omits the infamous "standard" operation, so this is more appropriate
  5938 than prove_goalw_cterm in many situations (e.g. in simprocs);
  5939 
  5940 * Pure: improved error reporting of simprocs;
  5941 
  5942 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  5943 up simprocs;
  5944 
  5945 
  5946 *** Document preparation ***
  5947 
  5948 * uses \par instead of \\ for line breaks in theory text. This may
  5949 shift some page breaks in large documents. To get the old behaviour
  5950 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  5951 
  5952 * minimized dependencies of isabelle.sty and isabellesym.sty on
  5953 other packages
  5954 
  5955 * \<euro> now needs package babel/greek instead of marvosym (which
  5956 broke \Rightarrow)
  5957 
  5958 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  5959 textcomp package)
  5960 
  5961 
  5962 
  5963 New in Isabelle2002 (March 2002)
  5964 --------------------------------
  5965 
  5966 *** Document preparation ***
  5967 
  5968 * greatly simplified document preparation setup, including more
  5969 graceful interpretation of isatool usedir -i/-d/-D options, and more
  5970 instructive isatool mkdir; users should basically be able to get
  5971 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  5972 users may run a separate document processing stage manually like this:
  5973 "isatool usedir -D output HOL Test && isatool document Test/output";
  5974 
  5975 * theory dependency graph may now be incorporated into documents;
  5976 isatool usedir -g true will produce session_graph.eps/.pdf for use
  5977 with \includegraphics of LaTeX;
  5978 
  5979 * proper spacing of consecutive markup elements, especially text
  5980 blocks after section headings;
  5981 
  5982 * support bold style (for single symbols only), input syntax is like
  5983 this: "\<^bold>\<alpha>" or "\<^bold>A";
  5984 
  5985 * \<bullet> is now output as bold \cdot by default, which looks much
  5986 better in printed text;
  5987 
  5988 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  5989 note that these symbols are currently unavailable in Proof General /
  5990 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  5991 
  5992 * isatool latex no longer depends on changed TEXINPUTS, instead
  5993 isatool document copies the Isabelle style files to the target
  5994 location;
  5995 
  5996 
  5997 *** Isar ***
  5998 
  5999 * Pure/Provers: improved proof by cases and induction;
  6000   - 'case' command admits impromptu naming of parameters (such as
  6001     "case (Suc n)");
  6002   - 'induct' method divinates rule instantiation from the inductive
  6003     claim; no longer requires excessive ?P bindings for proper
  6004     instantiation of cases;
  6005   - 'induct' method properly enumerates all possibilities of set/type
  6006     rules; as a consequence facts may be also passed through *type*
  6007     rules without further ado;
  6008   - 'induct' method now derives symbolic cases from the *rulified*
  6009     rule (before it used to rulify cases stemming from the internal
  6010     atomized version); this means that the context of a non-atomic
  6011     statement becomes is included in the hypothesis, avoiding the
  6012     slightly cumbersome show "PROP ?case" form;
  6013   - 'induct' may now use elim-style induction rules without chaining
  6014     facts, using ``missing'' premises from the goal state; this allows
  6015     rules stemming from inductive sets to be applied in unstructured
  6016     scripts, while still benefitting from proper handling of non-atomic
  6017     statements; NB: major inductive premises need to be put first, all
  6018     the rest of the goal is passed through the induction;
  6019   - 'induct' proper support for mutual induction involving non-atomic
  6020     rule statements (uses the new concept of simultaneous goals, see
  6021     below);
  6022   - append all possible rule selections, but only use the first
  6023     success (no backtracking);
  6024   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  6025   - undeclared rule case names default to numbers 1, 2, 3, ...;
  6026   - added 'print_induct_rules' (covered by help item in recent Proof
  6027     General versions);
  6028   - moved induct/cases attributes to Pure, methods to Provers;
  6029   - generic method setup instantiated for FOL and HOL;
  6030 
  6031 * Pure: support multiple simultaneous goal statements, for example
  6032 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  6033 meta-level mechanism, this acts as if several individual goals had
  6034 been stated separately; in particular common proof methods need to be
  6035 repeated in order to cover all claims; note that a single elimination
  6036 step is *not* sufficient to establish the two conjunctions, so this
  6037 fails:
  6038 
  6039   assume "A & B" then have A and B ..   (*".." fails*)
  6040 
  6041 better use "obtain" in situations as above; alternative refer to
  6042 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  6043 
  6044 * Pure: proper integration with ``locales''; unlike the original
  6045 version by Florian Kammller, Isar locales package high-level proof
  6046 contexts rather than raw logical ones (e.g. we admit to include
  6047 attributes everywhere); operations on locales include merge and
  6048 rename; support for implicit arguments (``structures''); simultaneous
  6049 type-inference over imports and text; see also HOL/ex/Locales.thy for
  6050 some examples;
  6051 
  6052 * Pure: the following commands have been ``localized'', supporting a
  6053 target locale specification "(in name)": 'lemma', 'theorem',
  6054 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  6055 stored both within the locale and at the theory level (exported and
  6056 qualified by the locale name);
  6057 
  6058 * Pure: theory goals may now be specified in ``long'' form, with
  6059 ad-hoc contexts consisting of arbitrary locale elements. for example
  6060 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  6061 definitions may be given, too); the result is a meta-level rule with
  6062 the context elements being discharged in the obvious way;
  6063 
  6064 * Pure: new proof command 'using' allows to augment currently used
  6065 facts after a goal statement ('using' is syntactically analogous to
  6066 'apply', but acts on the goal's facts only); this allows chained facts
  6067 to be separated into parts given before and after a claim, as in
  6068 ``from a and b have C using d and e <proof>'';
  6069 
  6070 * Pure: renamed "antecedent" case to "rule_context";
  6071 
  6072 * Pure: new 'judgment' command records explicit information about the
  6073 object-logic embedding (used by several tools internally); no longer
  6074 use hard-wired "Trueprop";
  6075 
  6076 * Pure: added 'corollary' command;
  6077 
  6078 * Pure: fixed 'token_translation' command;
  6079 
  6080 * Pure: removed obsolete 'exported' attribute;
  6081 
  6082 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  6083 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  6084 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  6085 
  6086 * Pure: method 'atomize' presents local goal premises as object-level
  6087 statements (atomic meta-level propositions); setup controlled via
  6088 rewrite rules declarations of 'atomize' attribute; example
  6089 application: 'induct' method with proper rule statements in improper
  6090 proof *scripts*;
  6091 
  6092 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  6093 now consider the syntactic context of assumptions, giving a better
  6094 chance to get type-inference of the arguments right (this is
  6095 especially important for locales);
  6096 
  6097 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  6098 mode;
  6099 
  6100 * Pure/obtain: the formal conclusion "thesis", being marked as
  6101 ``internal'', may no longer be reference directly in the text;
  6102 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  6103 situations;
  6104 
  6105 * Pure: generic 'sym' attribute which declares a rule both as pure
  6106 'elim?' and for the 'symmetric' operation;
  6107 
  6108 * Pure: marginal comments ``--'' may now occur just anywhere in the
  6109 text; the fixed correlation with particular command syntax has been
  6110 discontinued;
  6111 
  6112 * Pure: new method 'rules' is particularly well-suited for proof
  6113 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  6114 but often produces more compact proof terms with less detours;
  6115 
  6116 * Pure/Provers/classical: simplified integration with pure rule
  6117 attributes and methods; the classical "intro?/elim?/dest?"
  6118 declarations coincide with the pure ones; the "rule" method no longer
  6119 includes classically swapped intros; "intro" and "elim" methods no
  6120 longer pick rules from the context; also got rid of ML declarations
  6121 AddXIs/AddXEs/AddXDs; all of this has some potential for
  6122 INCOMPATIBILITY;
  6123 
  6124 * Provers/classical: attribute 'swapped' produces classical inversions
  6125 of introduction rules;
  6126 
  6127 * Provers/simplifier: 'simplified' attribute may refer to explicit
  6128 rules instead of full simplifier context; 'iff' attribute handles
  6129 conditional rules;
  6130 
  6131 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  6132 
  6133 * HOL: 'recdef' now fails on unfinished automated proofs, use
  6134 "(permissive)" option to recover old behavior;
  6135 
  6136 * HOL: 'inductive' no longer features separate (collective) attributes
  6137 for 'intros' (was found too confusing);
  6138 
  6139 * HOL: properly declared induction rules less_induct and
  6140 wf_induct_rule;
  6141 
  6142 
  6143 *** HOL ***
  6144 
  6145 * HOL: moved over to sane numeral syntax; the new policy is as
  6146 follows:
  6147 
  6148   - 0 and 1 are polymorphic constants, which are defined on any
  6149   numeric type (nat, int, real etc.);
  6150 
  6151   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  6152   binary representation internally;
  6153 
  6154   - type nat has special constructor Suc, and generally prefers Suc 0
  6155   over 1::nat and Suc (Suc 0) over 2::nat;
  6156 
  6157 This change may cause significant problems of INCOMPATIBILITY; here
  6158 are some hints on converting existing sources:
  6159 
  6160   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  6161   entities, so expressions involving "-" (unary or binary minus) need
  6162   to be spaced properly;
  6163 
  6164   - existing occurrences of "1" may need to be constraint "1::nat" or
  6165   even replaced by Suc 0; similar for old "2";
  6166 
  6167   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  6168 
  6169   - remove all special provisions on numerals in proofs;
  6170 
  6171 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  6172 representation (depends on bin_arith_simps in the default context);
  6173 
  6174 * HOL: symbolic syntax for x^2 (numeral 2);
  6175 
  6176 * HOL: the class of all HOL types is now called "type" rather than
  6177 "term"; INCOMPATIBILITY, need to adapt references to this type class
  6178 in axclass/classes, instance/arities, and (usually rare) occurrences
  6179 in typings (of consts etc.); internally the class is called
  6180 "HOL.type", ML programs should refer to HOLogic.typeS;
  6181 
  6182 * HOL/record package improvements:
  6183   - new derived operations "fields" to build a partial record section,
  6184     "extend" to promote a fixed record to a record scheme, and
  6185     "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*
  6186     declared as simp by default;
  6187   - shared operations ("more", "fields", etc.) now need to be always
  6188     qualified) --- potential INCOMPATIBILITY;
  6189   - removed "make_scheme" operations (use "make" with "extend") --
  6190     INCOMPATIBILITY;
  6191   - removed "more" class (simply use "term") -- INCOMPATIBILITY;
  6192   - provides cases/induct rules for use with corresponding Isar
  6193     methods (for concrete records, record schemes, concrete more
  6194     parts, and schematic more parts -- in that order);
  6195   - internal definitions directly based on a light-weight abstract
  6196     theory of product types over typedef rather than datatype;
  6197 
  6198 * HOL: generic code generator for generating executable ML code from
  6199 specifications; specific support for HOL constructs such as inductive
  6200 datatypes and sets, as well as recursive functions; can be invoked
  6201 via 'generate_code' theory section;
  6202 
  6203 * HOL: canonical cases/induct rules for n-tuples (n = 3..7);
  6204 
  6205 * HOL: consolidated and renamed several theories.  In particular:
  6206         Ord.thy has been absorbed into HOL.thy
  6207         String.thy has been absorbed into List.thy
  6208 
  6209 * HOL: concrete setsum syntax "\<Sum>i:A. b" == "setsum (%i. b) A"
  6210 (beware of argument permutation!);
  6211 
  6212 * HOL: linorder_less_split superseded by linorder_cases;
  6213 
  6214 * HOL/List: "nodups" renamed to "distinct";
  6215 
  6216 * HOL: added "The" definite description operator; move Hilbert's "Eps"
  6217 to peripheral theory "Hilbert_Choice"; some INCOMPATIBILITIES:
  6218   - Ex_def has changed, now need to use some_eq_ex
  6219 
  6220 * HOL: made split_all_tac safe; EXISTING PROOFS MAY FAIL OR LOOP, so
  6221 in this (rare) case use:
  6222 
  6223   delSWrapper "split_all_tac"
  6224   addSbefore ("unsafe_split_all_tac", unsafe_split_all_tac)
  6225 
  6226 * HOL: added safe wrapper "split_conv_tac" to claset; EXISTING PROOFS
  6227 MAY FAIL;
  6228 
  6229 * HOL: introduced f^n = f o ... o f; warning: due to the limits of
  6230 Isabelle's type classes, ^ on functions and relations has too general