NEWS
author wenzelm
Wed Apr 27 13:21:12 2011 +0200 (2011-04-27)
changeset 42484 2777a27506d0
parent 42403 38b29c9fc742
child 42502 13b41fb77649
permissions -rw-r--r--
predefined LaTeX macros for \<bind> and \<then>;
     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 
    80 *** Document preparation ***
    81 
    82 * New term style "isub" as ad-hoc conversion of variables x1, y23 into
    83 subscripted form x\<^isub>1, y\<^isub>2\<^isub>3.
    84 
    85 * Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
    86 (e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).
    87 
    88 
    89 *** ML ***
    90 
    91 * Structure Proof_Context follows standard naming scheme.  Old
    92 ProofContext is still available for some time as legacy alias.
    93 
    94 * Structure Timing provides various operations for timing; supersedes
    95 former start_timing/end_timing etc.
    96 
    97 * Path.print is the official way to show file-system paths to users
    98 (including quotes etc.).
    99 
   100 * Inner syntax: identifiers in parse trees of generic categories
   101 "logic", "aprop", "idt" etc. carry position information (disguised as
   102 type constraints).  Occasional INCOMPATIBILITY with non-compliant
   103 translations that choke on unexpected type constraints.  Positions can
   104 be stripped in ML translations via Syntax.strip_positions /
   105 Syntax.strip_positions_ast, or via the syntax constant
   106 "_strip_positions" within parse trees.  As last resort, positions can
   107 be disabled via the configuration option Syntax.positions, which is
   108 called "syntax_positions" in Isar attribute syntax.
   109 
   110 * Discontinued special status of various ML structures that contribute
   111 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
   112 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
   113 refer directly to Ast.Constant, Lexicon.is_identifier,
   114 Syntax_Trans.mk_binder_tr etc.
   115 
   116 * Typed print translation: discontinued show_sorts argument, which is
   117 already available via context of "advanced" translation.
   118 
   119 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
   120 goal states; body tactic needs to address all subgoals uniformly.
   121 
   122 * Slightly more special eq_list/eq_set, with shortcut involving
   123 pointer equality (assumes that eq relation is reflexive).
   124 
   125 
   126 
   127 New in Isabelle2011 (January 2011)
   128 ----------------------------------
   129 
   130 *** General ***
   131 
   132 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
   133 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
   134 useful tooltips and hyperlinks produced from its static analysis.  The
   135 bundled component provides an executable Isabelle tool that can be run
   136 like this:
   137 
   138   Isabelle2011/bin/isabelle jedit
   139 
   140 * Significantly improved Isabelle/Isar implementation manual.
   141 
   142 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
   143 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
   144 while the default heap location within that directory lacks that extra
   145 suffix.  This isolates multiple Isabelle installations from each
   146 other, avoiding problems with old settings in new versions.
   147 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
   148 
   149 * Source files are always encoded as UTF-8, instead of old-fashioned
   150 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
   151 the following package declarations:
   152 
   153   \usepackage[utf8]{inputenc}
   154   \usepackage{textcomp}
   155 
   156 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
   157 a Unicode character is treated as a single symbol, not a sequence of
   158 non-ASCII bytes as before.  Since Isabelle/ML string literals may
   159 contain symbols without further backslash escapes, Unicode can now be
   160 used here as well.  Recall that Symbol.explode in ML provides a
   161 consistent view on symbols, while raw explode (or String.explode)
   162 merely give a byte-oriented representation.
   163 
   164 * Theory loader: source files are primarily located via the master
   165 directory of each theory node (where the .thy file itself resides).
   166 The global load path is still partially available as legacy feature.
   167 Minor INCOMPATIBILITY due to subtle change in file lookup: use
   168 explicit paths, relatively to the theory.
   169 
   170 * Special treatment of ML file names has been discontinued.
   171 Historically, optional extensions .ML or .sml were added on demand --
   172 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
   173 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
   174 
   175 * Various options that affect pretty printing etc. are now properly
   176 handled within the context via configuration options, instead of
   177 unsynchronized references or print modes.  There are both ML Config.T
   178 entities and Isar declaration attributes to access these.
   179 
   180   ML (Config.T)                 Isar (attribute)
   181 
   182   eta_contract                  eta_contract
   183   show_brackets                 show_brackets
   184   show_sorts                    show_sorts
   185   show_types                    show_types
   186   show_question_marks           show_question_marks
   187   show_consts                   show_consts
   188   show_abbrevs                  show_abbrevs
   189 
   190   Syntax.ast_trace              syntax_ast_trace
   191   Syntax.ast_stat               syntax_ast_stat
   192   Syntax.ambiguity_level        syntax_ambiguity_level
   193 
   194   Goal_Display.goals_limit      goals_limit
   195   Goal_Display.show_main_goal   show_main_goal
   196 
   197   Method.rule_trace             rule_trace
   198 
   199   Thy_Output.display            thy_output_display
   200   Thy_Output.quotes             thy_output_quotes
   201   Thy_Output.indent             thy_output_indent
   202   Thy_Output.source             thy_output_source
   203   Thy_Output.break              thy_output_break
   204 
   205 Note that corresponding "..._default" references in ML may only be
   206 changed globally at the ROOT session setup, but *not* within a theory.
   207 The option "show_abbrevs" supersedes the former print mode
   208 "no_abbrevs" with inverted meaning.
   209 
   210 * More systematic naming of some configuration options.
   211 INCOMPATIBILITY.
   212 
   213   trace_simp  ~>  simp_trace
   214   debug_simp  ~>  simp_debug
   215 
   216 * Support for real valued configuration options, using simplistic
   217 floating-point notation that coincides with the inner syntax for
   218 float_token.
   219 
   220 * Support for real valued preferences (with approximative PGIP type):
   221 front-ends need to accept "pgint" values in float notation.
   222 INCOMPATIBILITY.
   223 
   224 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
   225 DejaVu Sans.
   226 
   227 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   228 
   229 
   230 *** Pure ***
   231 
   232 * Command 'type_synonym' (with single argument) replaces somewhat
   233 outdated 'types', which is still available as legacy feature for some
   234 time.
   235 
   236 * Command 'nonterminal' (with 'and' separated list of arguments)
   237 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
   238 
   239 * Command 'notepad' replaces former 'example_proof' for
   240 experimentation in Isar without any result.  INCOMPATIBILITY.
   241 
   242 * Locale interpretation commands 'interpret' and 'sublocale' accept
   243 lists of equations to map definitions in a locale to appropriate
   244 entities in the context of the interpretation.  The 'interpretation'
   245 command already provided this functionality.
   246 
   247 * Diagnostic command 'print_dependencies' prints the locale instances
   248 that would be activated if the specified expression was interpreted in
   249 the current context.  Variant "print_dependencies!" assumes a context
   250 without interpretations.
   251 
   252 * Diagnostic command 'print_interps' prints interpretations in proofs
   253 in addition to interpretations in theories.
   254 
   255 * Discontinued obsolete 'global' and 'local' commands to manipulate
   256 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
   257 Sign.root_path and Sign.local_path may be applied directly where this
   258 feature is still required for historical reasons.
   259 
   260 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
   261 'definition' instead.
   262 
   263 * The "prems" fact, which refers to the accidental collection of
   264 foundational premises in the context, is now explicitly marked as
   265 legacy feature and will be discontinued soon.  Consider using "assms"
   266 of the head statement or reference facts by explicit names.
   267 
   268 * Document antiquotations @{class} and @{type} print classes and type
   269 constructors.
   270 
   271 * Document antiquotation @{file} checks file/directory entries within
   272 the local file system.
   273 
   274 
   275 *** HOL ***
   276 
   277 * Coercive subtyping: functions can be declared as coercions and type
   278 inference will add them as necessary upon input of a term.  Theory
   279 Complex_Main declares real :: nat => real and real :: int => real as
   280 coercions. A coercion function f is declared like this:
   281 
   282   declare [[coercion f]]
   283 
   284 To lift coercions through type constructors (e.g. from nat => real to
   285 nat list => real list), map functions can be declared, e.g.
   286 
   287   declare [[coercion_map map]]
   288 
   289 Currently coercion inference is activated only in theories including
   290 real numbers, i.e. descendants of Complex_Main.  This is controlled by
   291 the configuration option "coercion_enabled", e.g. it can be enabled in
   292 other theories like this:
   293 
   294   declare [[coercion_enabled]]
   295 
   296 * Command 'partial_function' provides basic support for recursive
   297 function definitions over complete partial orders.  Concrete instances
   298 are provided for i) the option type, ii) tail recursion on arbitrary
   299 types, and iii) the heap monad of Imperative_HOL.  See
   300 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
   301 for examples.
   302 
   303 * Function package: f.psimps rules are no longer implicitly declared
   304 as [simp].  INCOMPATIBILITY.
   305 
   306 * Datatype package: theorems generated for executable equality (class
   307 "eq") carry proper names and are treated as default code equations.
   308 
   309 * Inductive package: now offers command 'inductive_simps' to
   310 automatically derive instantiated and simplified equations for
   311 inductive predicates, similar to 'inductive_cases'.
   312 
   313 * Command 'enriched_type' allows to register properties of the
   314 functorial structure of types.
   315 
   316 * Improved infrastructure for term evaluation using code generator
   317 techniques, in particular static evaluation conversions.
   318 
   319 * Code generator: Scala (2.8 or higher) has been added to the target
   320 languages.
   321 
   322 * Code generator: globbing constant expressions "*" and "Theory.*"
   323 have been replaced by the more idiomatic "_" and "Theory._".
   324 INCOMPATIBILITY.
   325 
   326 * Code generator: export_code without explicit file declaration prints
   327 to standard output.  INCOMPATIBILITY.
   328 
   329 * Code generator: do not print function definitions for case
   330 combinators any longer.
   331 
   332 * Code generator: simplification with rules determined with
   333 src/Tools/Code/code_simp.ML and method "code_simp".
   334 
   335 * Code generator for records: more idiomatic representation of record
   336 types.  Warning: records are not covered by ancient SML code
   337 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
   338 rep_datatype declaration helps to succeed then:
   339 
   340   record 'a foo = ...
   341   ...
   342   rep_datatype foo_ext ...
   343 
   344 * Records: logical foundation type for records does not carry a
   345 '_type' suffix any longer (obsolete due to authentic syntax).
   346 INCOMPATIBILITY.
   347 
   348 * Quickcheck now by default uses exhaustive testing instead of random
   349 testing.  Random testing can be invoked by "quickcheck [random]",
   350 exhaustive testing by "quickcheck [exhaustive]".
   351 
   352 * Quickcheck instantiates polymorphic types with small finite
   353 datatypes by default. This enables a simple execution mechanism to
   354 handle quantifiers and function equality over the finite datatypes.
   355 
   356 * Quickcheck random generator has been renamed from "code" to
   357 "random".  INCOMPATIBILITY.
   358 
   359 * Quickcheck now has a configurable time limit which is set to 30
   360 seconds by default. This can be changed by adding [timeout = n] to the
   361 quickcheck command. The time limit for Auto Quickcheck is still set
   362 independently.
   363 
   364 * Quickcheck in locales considers interpretations of that locale for
   365 counter example search.
   366 
   367 * Sledgehammer:
   368   - Added "smt" and "remote_smt" provers based on the "smt" proof
   369     method. See the Sledgehammer manual for details ("isabelle doc
   370     sledgehammer").
   371   - Renamed commands:
   372     sledgehammer atp_info ~> sledgehammer running_provers
   373     sledgehammer atp_kill ~> sledgehammer kill_provers
   374     sledgehammer available_atps ~> sledgehammer available_provers
   375     INCOMPATIBILITY.
   376   - Renamed options:
   377     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
   378     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
   379     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
   380     (and "ms" and "min" are no longer supported)
   381     INCOMPATIBILITY.
   382 
   383 * Nitpick:
   384   - Renamed options:
   385     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
   386     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
   387     INCOMPATIBILITY.
   388   - Added support for partial quotient types.
   389   - Added local versions of the "Nitpick.register_xxx" functions.
   390   - Added "whack" option.
   391   - Allow registration of quotient types as codatatypes.
   392   - Improved "merge_type_vars" option to merge more types.
   393   - Removed unsound "fast_descrs" option.
   394   - Added custom symmetry breaking for datatypes, making it possible to reach
   395     higher cardinalities.
   396   - Prevent the expansion of too large definitions.
   397 
   398 * Proof methods "metis" and "meson" now have configuration options
   399 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
   400 to diagnose these tools. E.g.
   401 
   402     using [[metis_trace = true]]
   403 
   404 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
   405 manually as command 'solve_direct'.
   406 
   407 * The default SMT solver Z3 must be enabled explicitly (due to
   408 licensing issues) by setting the environment variable
   409 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
   410 commercial applications, the SMT solver CVC3 is provided as fall-back;
   411 changing the SMT solver is done via the configuration option
   412 "smt_solver".
   413 
   414 * Remote SMT solvers need to be referred to by the "remote_" prefix,
   415 i.e. "remote_cvc3" and "remote_z3".
   416 
   417 * Added basic SMT support for datatypes, records, and typedefs using
   418 the oracle mode (no proofs).  Direct support of pairs has been dropped
   419 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
   420 support for a similar behavior).  Minor INCOMPATIBILITY.
   421 
   422 * Changed SMT configuration options:
   423   - Renamed:
   424     z3_proofs ~> smt_oracle (with inverted meaning)
   425     z3_trace_assms ~> smt_trace_used_facts
   426     INCOMPATIBILITY.
   427   - Added:
   428     smt_verbose
   429     smt_random_seed
   430     smt_datatypes
   431     smt_infer_triggers
   432     smt_monomorph_limit
   433     cvc3_options
   434     remote_cvc3_options
   435     remote_z3_options
   436     yices_options
   437 
   438 * Boogie output files (.b2i files) need to be declared in the theory
   439 header.
   440 
   441 * Simplification procedure "list_to_set_comprehension" rewrites list
   442 comprehensions applied to List.set to set comprehensions.  Occasional
   443 INCOMPATIBILITY, may be deactivated like this:
   444 
   445   declare [[simproc del: list_to_set_comprehension]]
   446 
   447 * Removed old version of primrec package.  INCOMPATIBILITY.
   448 
   449 * Removed simplifier congruence rule of "prod_case", as has for long
   450 been the case with "split".  INCOMPATIBILITY.
   451 
   452 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
   453 
   454 * Removed [split_format ... and ... and ...] version of
   455 [split_format].  Potential INCOMPATIBILITY.
   456 
   457 * Predicate "sorted" now defined inductively, with nice induction
   458 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
   459 
   460 * Constant "contents" renamed to "the_elem", to free the generic name
   461 contents for other uses.  INCOMPATIBILITY.
   462 
   463 * Renamed class eq and constant eq (for code generation) to class
   464 equal and constant equal, plus renaming of related facts and various
   465 tuning.  INCOMPATIBILITY.
   466 
   467 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
   468 
   469 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
   470 INCOMPATIBILITY.
   471 
   472 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
   473 avoid confusion with finite sets.  INCOMPATIBILITY.
   474 
   475 * Abandoned locales equiv, congruent and congruent2 for equivalence
   476 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
   477 for congruent(2)).
   478 
   479 * Some previously unqualified names have been qualified:
   480 
   481   types
   482     bool ~> HOL.bool
   483     nat ~> Nat.nat
   484 
   485   constants
   486     Trueprop ~> HOL.Trueprop
   487     True ~> HOL.True
   488     False ~> HOL.False
   489     op & ~> HOL.conj
   490     op | ~> HOL.disj
   491     op --> ~> HOL.implies
   492     op = ~> HOL.eq
   493     Not ~> HOL.Not
   494     The ~> HOL.The
   495     All ~> HOL.All
   496     Ex ~> HOL.Ex
   497     Ex1 ~> HOL.Ex1
   498     Let ~> HOL.Let
   499     If ~> HOL.If
   500     Ball ~> Set.Ball
   501     Bex ~> Set.Bex
   502     Suc ~> Nat.Suc
   503     Pair ~> Product_Type.Pair
   504     fst ~> Product_Type.fst
   505     snd ~> Product_Type.snd
   506     curry ~> Product_Type.curry
   507     op : ~> Set.member
   508     Collect ~> Set.Collect
   509 
   510 INCOMPATIBILITY.
   511 
   512 * More canonical naming convention for some fundamental definitions:
   513 
   514     bot_bool_eq ~> bot_bool_def
   515     top_bool_eq ~> top_bool_def
   516     inf_bool_eq ~> inf_bool_def
   517     sup_bool_eq ~> sup_bool_def
   518     bot_fun_eq  ~> bot_fun_def
   519     top_fun_eq  ~> top_fun_def
   520     inf_fun_eq  ~> inf_fun_def
   521     sup_fun_eq  ~> sup_fun_def
   522 
   523 INCOMPATIBILITY.
   524 
   525 * More stylized fact names:
   526 
   527   expand_fun_eq ~> fun_eq_iff
   528   expand_set_eq ~> set_eq_iff
   529   set_ext       ~> set_eqI
   530   nat_number    ~> eval_nat_numeral
   531 
   532 INCOMPATIBILITY.
   533 
   534 * Refactoring of code-generation specific operations in theory List:
   535 
   536   constants
   537     null ~> List.null
   538 
   539   facts
   540     mem_iff ~> member_def
   541     null_empty ~> null_def
   542 
   543 INCOMPATIBILITY.  Note that these were not supposed to be used
   544 regularly unless for striking reasons; their main purpose was code
   545 generation.
   546 
   547 Various operations from the Haskell prelude are used for generating
   548 Haskell code.
   549 
   550 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
   551 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
   552 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
   553 
   554 * Abolished some non-alphabetic type names: "prod" and "sum" replace
   555 "*" and "+" respectively.  INCOMPATIBILITY.
   556 
   557 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
   558 "Sum_Type.Plus" instead.
   559 
   560 * Constant "split" has been merged with constant "prod_case"; names of
   561 ML functions, facts etc. involving split have been retained so far,
   562 though.  INCOMPATIBILITY.
   563 
   564 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
   565 instead.  INCOMPATIBILITY.
   566 
   567 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
   568 INCOMPATIBILITY.
   569 
   570 * Former theory Library/Enum is now part of the HOL-Main image.
   571 INCOMPATIBILITY: all constants of the Enum theory now have to be
   572 referred to by its qualified name.
   573 
   574   enum    ~>  Enum.enum
   575   nlists  ~>  Enum.nlists
   576   product ~>  Enum.product
   577 
   578 * Theory Library/Monad_Syntax provides do-syntax for monad types.
   579 Syntax in Library/State_Monad has been changed to avoid ambiguities.
   580 INCOMPATIBILITY.
   581 
   582 * Theory Library/SetsAndFunctions has been split into
   583 Library/Function_Algebras and Library/Set_Algebras; canonical names
   584 for instance definitions for functions; various improvements.
   585 INCOMPATIBILITY.
   586 
   587 * Theory Library/Multiset provides stable quicksort implementation of
   588 sort_key.
   589 
   590 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
   591 INCOMPATIBILITY.
   592 
   593 * Session Multivariate_Analysis: introduced a type class for euclidean
   594 space.  Most theorems are now stated in terms of euclidean spaces
   595 instead of finite cartesian products.
   596 
   597   types
   598     real ^ 'n ~>  'a::real_vector
   599               ~>  'a::euclidean_space
   600               ~>  'a::ordered_euclidean_space
   601         (depends on your needs)
   602 
   603   constants
   604      _ $ _        ~> _ $$ _
   605      \<chi> x. _  ~> \<chi>\<chi> x. _
   606      CARD('n)     ~> DIM('a)
   607 
   608 Also note that the indices are now natural numbers and not from some
   609 finite type. Finite cartesian products of euclidean spaces, products
   610 of euclidean spaces the real and complex numbers are instantiated to
   611 be euclidean_spaces.  INCOMPATIBILITY.
   612 
   613 * Session Probability: introduced pextreal as positive extended real
   614 numbers.  Use pextreal as value for measures.  Introduce the
   615 Radon-Nikodym derivative, product spaces and Fubini's theorem for
   616 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
   617 the integral in Multivariate Analysis.  INCOMPATIBILITY.
   618 
   619 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   620 INCOMPATIBILITY.
   621 
   622 * Session SPARK (with image HOL-SPARK) provides commands to load and
   623 prove verification conditions generated by the SPARK Ada program
   624 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
   625 
   626 
   627 *** HOL-Algebra ***
   628 
   629 * Theorems for additive ring operations (locale abelian_monoid and
   630 descendants) are generated by interpretation from their multiplicative
   631 counterparts.  Names (in particular theorem names) have the mandatory
   632 qualifier 'add'.  Previous theorem names are redeclared for
   633 compatibility.
   634 
   635 * Structure "int_ring" is now an abbreviation (previously a
   636 definition).  This fits more natural with advanced interpretations.
   637 
   638 
   639 *** HOLCF ***
   640 
   641 * The domain package now runs in definitional mode by default: The
   642 former command 'new_domain' is now called 'domain'.  To use the domain
   643 package in its original axiomatic mode, use 'domain (unsafe)'.
   644 INCOMPATIBILITY.
   645 
   646 * The new class "domain" is now the default sort.  Class "predomain"
   647 is an unpointed version of "domain". Theories can be updated by
   648 replacing sort annotations as shown below.  INCOMPATIBILITY.
   649 
   650   'a::type ~> 'a::countable
   651   'a::cpo  ~> 'a::predomain
   652   'a::pcpo ~> 'a::domain
   653 
   654 * The old type class "rep" has been superseded by class "domain".
   655 Accordingly, users of the definitional package must remove any
   656 "default_sort rep" declarations.  INCOMPATIBILITY.
   657 
   658 * The domain package (definitional mode) now supports unpointed
   659 predomain argument types, as long as they are marked 'lazy'. (Strict
   660 arguments must be in class "domain".) For example, the following
   661 domain definition now works:
   662 
   663   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
   664 
   665 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
   666 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
   667 'a option, and 'a list.  Additionally, it configures fixrec and the
   668 domain package to work with these types.  For example:
   669 
   670   fixrec isInl :: "('a + 'b) u -> tr"
   671     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
   672 
   673   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
   674 
   675 * The "(permissive)" option of fixrec has been replaced with a
   676 per-equation "(unchecked)" option. See
   677 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
   678 
   679 * The "bifinite" class no longer fixes a constant "approx"; the class
   680 now just asserts that such a function exists.  INCOMPATIBILITY.
   681 
   682 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
   683 defines an embedding of type 'a defl into udom by default; instances
   684 of "bifinite" and "domain" classes are available in
   685 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
   686 
   687 * The syntax "REP('a)" has been replaced with "DEFL('a)".
   688 
   689 * The predicate "directed" has been removed.  INCOMPATIBILITY.
   690 
   691 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
   692 
   693 * The function "cprod_map" has been renamed to "prod_map".
   694 INCOMPATIBILITY.
   695 
   696 * The monadic bind operator on each powerdomain has new binder syntax
   697 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
   698 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
   699 
   700 * The infix syntax for binary union on each powerdomain has changed
   701 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
   702 syntax.  INCOMPATIBILITY.
   703 
   704 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
   705 still supported as an input translation.
   706 
   707 * Renamed some theorems (the original names are also still available).
   708 
   709   expand_fun_below   ~> fun_below_iff
   710   below_fun_ext      ~> fun_belowI
   711   expand_cfun_eq     ~> cfun_eq_iff
   712   ext_cfun           ~> cfun_eqI
   713   expand_cfun_below  ~> cfun_below_iff
   714   below_cfun_ext     ~> cfun_belowI
   715   cont2cont_Rep_CFun ~> cont2cont_APP
   716 
   717 * The Abs and Rep functions for various types have changed names.
   718 Related theorem names have also changed to match. INCOMPATIBILITY.
   719 
   720   Rep_CFun  ~> Rep_cfun
   721   Abs_CFun  ~> Abs_cfun
   722   Rep_Sprod ~> Rep_sprod
   723   Abs_Sprod ~> Abs_sprod
   724   Rep_Ssum  ~> Rep_ssum
   725   Abs_Ssum  ~> Abs_ssum
   726 
   727 * Lemmas with names of the form *_defined_iff or *_strict_iff have
   728 been renamed to *_bottom_iff.  INCOMPATIBILITY.
   729 
   730 * Various changes to bisimulation/coinduction with domain package:
   731 
   732   - Definitions of "bisim" constants no longer mention definedness.
   733   - With mutual recursion, "bisim" predicate is now curried.
   734   - With mutual recursion, each type gets a separate coind theorem.
   735   - Variable names in bisim_def and coinduct rules have changed.
   736 
   737 INCOMPATIBILITY.
   738 
   739 * Case combinators generated by the domain package for type "foo" are
   740 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
   741 
   742 * Several theorems have been renamed to more accurately reflect the
   743 names of constants and types involved.  INCOMPATIBILITY.
   744 
   745   thelub_const    ~> lub_const
   746   lub_const       ~> is_lub_const
   747   thelubI         ~> lub_eqI
   748   is_lub_lub      ~> is_lubD2
   749   lubI            ~> is_lub_lub
   750   unique_lub      ~> is_lub_unique
   751   is_ub_lub       ~> is_lub_rangeD1
   752   lub_bin_chain   ~> is_lub_bin_chain
   753   lub_fun         ~> is_lub_fun
   754   thelub_fun      ~> lub_fun
   755   thelub_cfun     ~> lub_cfun
   756   thelub_Pair     ~> lub_Pair
   757   lub_cprod       ~> is_lub_prod
   758   thelub_cprod    ~> lub_prod
   759   minimal_cprod   ~> minimal_prod
   760   inst_cprod_pcpo ~> inst_prod_pcpo
   761   UU_I            ~> bottomI
   762   compact_UU      ~> compact_bottom
   763   deflation_UU    ~> deflation_bottom
   764   finite_deflation_UU ~> finite_deflation_bottom
   765 
   766 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
   767 
   768   sq_ord_less_eq_trans ~> below_eq_trans
   769   sq_ord_eq_less_trans ~> eq_below_trans
   770   refl_less            ~> below_refl
   771   trans_less           ~> below_trans
   772   antisym_less         ~> below_antisym
   773   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
   774   box_less             ~> box_below
   775   rev_trans_less       ~> rev_below_trans
   776   not_less2not_eq      ~> not_below2not_eq
   777   less_UU_iff          ~> below_UU_iff
   778   flat_less_iff        ~> flat_below_iff
   779   adm_less             ~> adm_below
   780   adm_not_less         ~> adm_not_below
   781   adm_compact_not_less ~> adm_compact_not_below
   782   less_fun_def         ~> below_fun_def
   783   expand_fun_less      ~> fun_below_iff
   784   less_fun_ext         ~> fun_belowI
   785   less_discr_def       ~> below_discr_def
   786   discr_less_eq        ~> discr_below_eq
   787   less_unit_def        ~> below_unit_def
   788   less_cprod_def       ~> below_prod_def
   789   prod_lessI           ~> prod_belowI
   790   Pair_less_iff        ~> Pair_below_iff
   791   fst_less_iff         ~> fst_below_iff
   792   snd_less_iff         ~> snd_below_iff
   793   expand_cfun_less     ~> cfun_below_iff
   794   less_cfun_ext        ~> cfun_belowI
   795   injection_less       ~> injection_below
   796   less_up_def          ~> below_up_def
   797   not_Iup_less         ~> not_Iup_below
   798   Iup_less             ~> Iup_below
   799   up_less              ~> up_below
   800   Def_inject_less_eq   ~> Def_below_Def
   801   Def_less_is_eq       ~> Def_below_iff
   802   spair_less_iff       ~> spair_below_iff
   803   less_sprod           ~> below_sprod
   804   spair_less           ~> spair_below
   805   sfst_less_iff        ~> sfst_below_iff
   806   ssnd_less_iff        ~> ssnd_below_iff
   807   fix_least_less       ~> fix_least_below
   808   dist_less_one        ~> dist_below_one
   809   less_ONE             ~> below_ONE
   810   ONE_less_iff         ~> ONE_below_iff
   811   less_sinlD           ~> below_sinlD
   812   less_sinrD           ~> below_sinrD
   813 
   814 
   815 *** FOL and ZF ***
   816 
   817 * All constant names are now qualified internally and use proper
   818 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
   819 
   820 
   821 *** ML ***
   822 
   823 * Antiquotation @{assert} inlines a function bool -> unit that raises
   824 Fail if the argument is false.  Due to inlining the source position of
   825 failed assertions is included in the error output.
   826 
   827 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
   828 text is in practice always evaluated with a stable theory checkpoint.
   829 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
   830 
   831 * Antiquotation @{theory A} refers to theory A from the ancestry of
   832 the current context, not any accidental theory loader state as before.
   833 Potential INCOMPATIBILITY, subtle change in semantics.
   834 
   835 * Syntax.pretty_priority (default 0) configures the required priority
   836 of pretty-printed output and thus affects insertion of parentheses.
   837 
   838 * Syntax.default_root (default "any") configures the inner syntax
   839 category (nonterminal symbol) for parsing of terms.
   840 
   841 * Former exception Library.UnequalLengths now coincides with
   842 ListPair.UnequalLengths.
   843 
   844 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
   845 main functionality is provided by structure Simplifier.
   846 
   847 * Renamed raw "explode" function to "raw_explode" to emphasize its
   848 meaning.  Note that internally to Isabelle, Symbol.explode is used in
   849 almost all situations.
   850 
   851 * Discontinued obsolete function sys_error and exception SYS_ERROR.
   852 See implementation manual for further details on exceptions in
   853 Isabelle/ML.
   854 
   855 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
   856 meaning.
   857 
   858 * Renamed structure PureThy to Pure_Thy and moved most of its
   859 operations to structure Global_Theory, to emphasize that this is
   860 rarely-used global-only stuff.
   861 
   862 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
   863 instead (or tracing for high-volume output).
   864 
   865 * Configuration option show_question_marks only affects regular pretty
   866 printing of types and terms, not raw Term.string_of_vname.
   867 
   868 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
   869 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
   870 @{thms} for most purposes.
   871 
   872 * ML structure Unsynchronized is never opened, not even in Isar
   873 interaction mode as before.  Old Unsynchronized.set etc. have been
   874 discontinued -- use plain := instead.  This should be *rare* anyway,
   875 since modern tools always work via official context data, notably
   876 configuration options.
   877 
   878 * Parallel and asynchronous execution requires special care concerning
   879 interrupts.  Structure Exn provides some convenience functions that
   880 avoid working directly with raw Interrupt.  User code must not absorb
   881 interrupts -- intermediate handling (for cleanup etc.) needs to be
   882 followed by re-raising of the original exception.  Another common
   883 source of mistakes are "handle _" patterns, which make the meaning of
   884 the program subject to physical effects of the environment.
   885 
   886 
   887 
   888 New in Isabelle2009-2 (June 2010)
   889 ---------------------------------
   890 
   891 *** General ***
   892 
   893 * Authentic syntax for *all* logical entities (type classes, type
   894 constructors, term constants): provides simple and robust
   895 correspondence between formal entities and concrete syntax.  Within
   896 the parse tree / AST representations, "constants" are decorated by
   897 their category (class, type, const) and spelled out explicitly with
   898 their full internal name.
   899 
   900 Substantial INCOMPATIBILITY concerning low-level syntax declarations
   901 and translations (translation rules and translation functions in ML).
   902 Some hints on upgrading:
   903 
   904   - Many existing uses of 'syntax' and 'translations' can be replaced
   905     by more modern 'type_notation', 'notation' and 'abbreviation',
   906     which are independent of this issue.
   907 
   908   - 'translations' require markup within the AST; the term syntax
   909     provides the following special forms:
   910 
   911       CONST c   -- produces syntax version of constant c from context
   912       XCONST c  -- literally c, checked as constant from context
   913       c         -- literally c, if declared by 'syntax'
   914 
   915     Plain identifiers are treated as AST variables -- occasionally the
   916     system indicates accidental variables via the error "rhs contains
   917     extra variables".
   918 
   919     Type classes and type constructors are marked according to their
   920     concrete syntax.  Some old translations rules need to be written
   921     for the "type" category, using type constructor application
   922     instead of pseudo-term application of the default category
   923     "logic".
   924 
   925   - 'parse_translation' etc. in ML may use the following
   926     antiquotations:
   927 
   928       @{class_syntax c}   -- type class c within parse tree / AST
   929       @{term_syntax c}    -- type constructor c within parse tree / AST
   930       @{const_syntax c}   -- ML version of "CONST c" above
   931       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
   932 
   933   - Literal types within 'typed_print_translations', i.e. those *not*
   934     represented as pseudo-terms are represented verbatim.  Use @{class
   935     c} or @{type_name c} here instead of the above syntax
   936     antiquotations.
   937 
   938 Note that old non-authentic syntax was based on unqualified base
   939 names, so all of the above "constant" names would coincide.  Recall
   940 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
   941 diagnose syntax problems.
   942 
   943 * Type constructors admit general mixfix syntax, not just infix.
   944 
   945 * Concrete syntax may be attached to local entities without a proof
   946 body, too.  This works via regular mixfix annotations for 'fix',
   947 'def', 'obtain' etc. or via the explicit 'write' command, which is
   948 similar to the 'notation' command in theory specifications.
   949 
   950 * Discontinued unnamed infix syntax (legacy feature for many years) --
   951 need to specify constant name and syntax separately.  Internal ML
   952 datatype constructors have been renamed from InfixName to Infix etc.
   953 Minor INCOMPATIBILITY.
   954 
   955 * Schematic theorem statements need to be explicitly markup as such,
   956 via commands 'schematic_lemma', 'schematic_theorem',
   957 'schematic_corollary'.  Thus the relevance of the proof is made
   958 syntactically clear, which impacts performance in a parallel or
   959 asynchronous interactive environment.  Minor INCOMPATIBILITY.
   960 
   961 * Use of cumulative prems via "!" in some proof methods has been
   962 discontinued (old legacy feature).
   963 
   964 * References 'trace_simp' and 'debug_simp' have been replaced by
   965 configuration options stored in the context. Enabling tracing (the
   966 case of debugging is similar) in proofs works via
   967 
   968   using [[trace_simp = true]]
   969 
   970 Tracing is then active for all invocations of the simplifier in
   971 subsequent goal refinement steps. Tracing may also still be enabled or
   972 disabled via the ProofGeneral settings menu.
   973 
   974 * Separate commands 'hide_class', 'hide_type', 'hide_const',
   975 'hide_fact' replace the former 'hide' KIND command.  Minor
   976 INCOMPATIBILITY.
   977 
   978 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
   979 more efficient than combinations with -q1 or -q2.
   980 
   981 
   982 *** Pure ***
   983 
   984 * Proofterms record type-class reasoning explicitly, using the
   985 "unconstrain" operation internally.  This eliminates all sort
   986 constraints from a theorem and proof, introducing explicit
   987 OFCLASS-premises.  On the proof term level, this operation is
   988 automatically applied at theorem boundaries, such that closed proofs
   989 are always free of sort constraints.  INCOMPATIBILITY for tools that
   990 inspect proof terms.
   991 
   992 * Local theory specifications may depend on extra type variables that
   993 are not present in the result type -- arguments TYPE('a) :: 'a itself
   994 are added internally.  For example:
   995 
   996   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
   997 
   998 * Predicates of locales introduced by classes carry a mandatory
   999 "class" prefix.  INCOMPATIBILITY.
  1000 
  1001 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
  1002 
  1003 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
  1004 'class' instead.
  1005 
  1006 * Command 'code_reflect' allows to incorporate generated ML code into
  1007 runtime environment; replaces immature code_datatype antiquotation.
  1008 INCOMPATIBILITY.
  1009 
  1010 * Code generator: simple concept for abstract datatypes obeying
  1011 invariants.
  1012 
  1013 * Code generator: details of internal data cache have no impact on the
  1014 user space functionality any longer.
  1015 
  1016 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  1017 subgoals.  This is more appropriate for interpretations with 'where'.
  1018 INCOMPATIBILITY.
  1019 
  1020 * Command 'example_proof' opens an empty proof body.  This allows to
  1021 experiment with Isar, without producing any persistent result.
  1022 
  1023 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  1024 within a local theory context, with explicit checking of the
  1025 constructors involved (in contrast to the raw 'syntax' versions).
  1026 
  1027 * Commands 'types' and 'typedecl' now work within a local theory
  1028 context -- without introducing dependencies on parameters or
  1029 assumptions, which is not possible in Isabelle/Pure.
  1030 
  1031 * Command 'defaultsort' has been renamed to 'default_sort', it works
  1032 within a local theory context.  Minor INCOMPATIBILITY.
  1033 
  1034 
  1035 *** HOL ***
  1036 
  1037 * Command 'typedef' now works within a local theory context -- without
  1038 introducing dependencies on parameters or assumptions, which is not
  1039 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  1040 contain multiple interpretations of local typedefs (with different
  1041 non-emptiness proofs), even in a global theory context.
  1042 
  1043 * New package for quotient types.  Commands 'quotient_type' and
  1044 'quotient_definition' may be used for defining types and constants by
  1045 quotient constructions.  An example is the type of integers created by
  1046 quotienting pairs of natural numbers:
  1047 
  1048   fun
  1049     intrel :: "(nat * nat) => (nat * nat) => bool"
  1050   where
  1051     "intrel (x, y) (u, v) = (x + v = u + y)"
  1052 
  1053   quotient_type int = "nat * nat" / intrel
  1054     by (auto simp add: equivp_def expand_fun_eq)
  1055 
  1056   quotient_definition
  1057     "0::int" is "(0::nat, 0::nat)"
  1058 
  1059 The method "lifting" can be used to lift of theorems from the
  1060 underlying "raw" type to the quotient type.  The example
  1061 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  1062 construction and provides a reasoning infrastructure for finite sets.
  1063 
  1064 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  1065 clash with new theory Quotient in Main HOL.
  1066 
  1067 * Moved the SMT binding into the main HOL session, eliminating
  1068 separate HOL-SMT session.
  1069 
  1070 * List membership infix mem operation is only an input abbreviation.
  1071 INCOMPATIBILITY.
  1072 
  1073 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  1074 for future developements; former Library/Word.thy is still present in
  1075 the AFP entry RSAPPS.
  1076 
  1077 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  1078 longer shadowed.  INCOMPATIBILITY.
  1079 
  1080 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  1081 INCOMPATIBILITY.
  1082 
  1083 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  1084 INCOMPATIBILITY.
  1085 
  1086 * Dropped normalizing_semiring etc; use the facts in semiring classes
  1087 instead.  INCOMPATIBILITY.
  1088 
  1089 * Dropped several real-specific versions of lemmas about floor and
  1090 ceiling; use the generic lemmas from theory "Archimedean_Field"
  1091 instead.  INCOMPATIBILITY.
  1092 
  1093   floor_number_of_eq         ~> floor_number_of
  1094   le_floor_eq_number_of      ~> number_of_le_floor
  1095   le_floor_eq_zero           ~> zero_le_floor
  1096   le_floor_eq_one            ~> one_le_floor
  1097   floor_less_eq_number_of    ~> floor_less_number_of
  1098   floor_less_eq_zero         ~> floor_less_zero
  1099   floor_less_eq_one          ~> floor_less_one
  1100   less_floor_eq_number_of    ~> number_of_less_floor
  1101   less_floor_eq_zero         ~> zero_less_floor
  1102   less_floor_eq_one          ~> one_less_floor
  1103   floor_le_eq_number_of      ~> floor_le_number_of
  1104   floor_le_eq_zero           ~> floor_le_zero
  1105   floor_le_eq_one            ~> floor_le_one
  1106   floor_subtract_number_of   ~> floor_diff_number_of
  1107   floor_subtract_one         ~> floor_diff_one
  1108   ceiling_number_of_eq       ~> ceiling_number_of
  1109   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  1110   ceiling_le_zero_eq         ~> ceiling_le_zero
  1111   ceiling_le_eq_one          ~> ceiling_le_one
  1112   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  1113   less_ceiling_eq_zero       ~> zero_less_ceiling
  1114   less_ceiling_eq_one        ~> one_less_ceiling
  1115   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  1116   ceiling_less_eq_zero       ~> ceiling_less_zero
  1117   ceiling_less_eq_one        ~> ceiling_less_one
  1118   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  1119   le_ceiling_eq_zero         ~> zero_le_ceiling
  1120   le_ceiling_eq_one          ~> one_le_ceiling
  1121   ceiling_subtract_number_of ~> ceiling_diff_number_of
  1122   ceiling_subtract_one       ~> ceiling_diff_one
  1123 
  1124 * Theory "Finite_Set": various folding_XXX locales facilitate the
  1125 application of the various fold combinators on finite sets.
  1126 
  1127 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  1128 provides abstract red-black tree type which is backed by "RBT_Impl" as
  1129 implementation.  INCOMPATIBILTY.
  1130 
  1131 * Theory Library/Coinductive_List has been removed -- superseded by
  1132 AFP/thys/Coinductive.
  1133 
  1134 * Theory PReal, including the type "preal" and related operations, has
  1135 been removed.  INCOMPATIBILITY.
  1136 
  1137 * Real: new development using Cauchy Sequences.
  1138 
  1139 * Split off theory "Big_Operators" containing setsum, setprod,
  1140 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  1141 
  1142 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  1143 "Int" etc.  INCOMPATIBILITY.
  1144 
  1145 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  1146 
  1147 * New set of rules "ac_simps" provides combined assoc / commute
  1148 rewrites for all interpretations of the appropriate generic locales.
  1149 
  1150 * Renamed theory "OrderedGroup" to "Groups" and split theory
  1151 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  1152 appropriate and more consistent names suitable for name prefixes
  1153 within the HOL theories.  INCOMPATIBILITY.
  1154 
  1155 * Some generic constants have been put to appropriate theories:
  1156   - less_eq, less: Orderings
  1157   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  1158   - inverse, divide: Rings
  1159 INCOMPATIBILITY.
  1160 
  1161 * More consistent naming of type classes involving orderings (and
  1162 lattices):
  1163 
  1164     lower_semilattice                   ~> semilattice_inf
  1165     upper_semilattice                   ~> semilattice_sup
  1166 
  1167     dense_linear_order                  ~> dense_linorder
  1168 
  1169     pordered_ab_group_add               ~> ordered_ab_group_add
  1170     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  1171     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  1172     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  1173     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  1174     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  1175     pordered_cancel_semiring            ~> ordered_cancel_semiring
  1176     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  1177     pordered_comm_ring                  ~> ordered_comm_ring
  1178     pordered_comm_semiring              ~> ordered_comm_semiring
  1179     pordered_ring                       ~> ordered_ring
  1180     pordered_ring_abs                   ~> ordered_ring_abs
  1181     pordered_semiring                   ~> ordered_semiring
  1182 
  1183     ordered_ab_group_add                ~> linordered_ab_group_add
  1184     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  1185     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  1186     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  1187     ordered_field                       ~> linordered_field
  1188     ordered_field_no_lb                 ~> linordered_field_no_lb
  1189     ordered_field_no_ub                 ~> linordered_field_no_ub
  1190     ordered_field_dense_linear_order    ~> dense_linordered_field
  1191     ordered_idom                        ~> linordered_idom
  1192     ordered_ring                        ~> linordered_ring
  1193     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  1194     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  1195     ordered_ring_strict                 ~> linordered_ring_strict
  1196     ordered_semidom                     ~> linordered_semidom
  1197     ordered_semiring                    ~> linordered_semiring
  1198     ordered_semiring_1                  ~> linordered_semiring_1
  1199     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  1200     ordered_semiring_strict             ~> linordered_semiring_strict
  1201 
  1202   The following slightly odd type classes have been moved to a
  1203   separate theory Library/Lattice_Algebras:
  1204 
  1205     lordered_ab_group_add               ~> lattice_ab_group_add
  1206     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  1207     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  1208     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  1209     lordered_ring                       ~> lattice_ring
  1210 
  1211 INCOMPATIBILITY.
  1212 
  1213 * Refined field classes:
  1214   - classes division_ring_inverse_zero, field_inverse_zero,
  1215     linordered_field_inverse_zero include rule inverse 0 = 0 --
  1216     subsumes former division_by_zero class;
  1217   - numerous lemmas have been ported from field to division_ring.
  1218 INCOMPATIBILITY.
  1219 
  1220 * Refined algebra theorem collections:
  1221   - dropped theorem group group_simps, use algebra_simps instead;
  1222   - dropped theorem group ring_simps, use field_simps instead;
  1223   - proper theorem collection field_simps subsumes former theorem
  1224     groups field_eq_simps and field_simps;
  1225   - dropped lemma eq_minus_self_iff which is a duplicate for
  1226     equal_neg_zero.
  1227 INCOMPATIBILITY.
  1228 
  1229 * Theory Finite_Set and List: some lemmas have been generalized from
  1230 sets to lattices:
  1231 
  1232   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  1233   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  1234   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  1235   union_Union_fold_union        ~> sup_Sup_fold_sup
  1236   Inter_fold_inter              ~> Inf_fold_inf
  1237   Union_fold_union              ~> Sup_fold_sup
  1238   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  1239   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  1240   INTER_fold_inter              ~> INFI_fold_inf
  1241   UNION_fold_union              ~> SUPR_fold_sup
  1242 
  1243 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  1244 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  1245 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  1246 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  1247 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  1248 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  1249 
  1250 * Reorganized theory Multiset: swapped notation of pointwise and
  1251 multiset order:
  1252 
  1253   - pointwise ordering is instance of class order with standard syntax
  1254     <= and <;
  1255   - multiset ordering has syntax <=# and <#; partial order properties
  1256     are provided by means of interpretation with prefix
  1257     multiset_order;
  1258   - less duplication, less historical organization of sections,
  1259     conversion from associations lists to multisets, rudimentary code
  1260     generation;
  1261   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  1262     if needed.
  1263 
  1264 Renamed:
  1265 
  1266   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  1267   multi_count_ext  ~>  multiset_ext
  1268   diff_union_inverse2  ~>  diff_union_cancelR
  1269 
  1270 INCOMPATIBILITY.
  1271 
  1272 * Theory Permutation: replaced local "remove" by List.remove1.
  1273 
  1274 * Code generation: ML and OCaml code is decorated with signatures.
  1275 
  1276 * Theory List: added transpose.
  1277 
  1278 * Library/Nat_Bijection.thy is a collection of bijective functions
  1279 between nat and other types, which supersedes the older libraries
  1280 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  1281 
  1282   Constants:
  1283   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  1284   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  1285   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  1286   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  1287   Countable.pair_encode           ~> prod_encode
  1288   NatIso.prod2nat                 ~> prod_encode
  1289   NatIso.nat2prod                 ~> prod_decode
  1290   NatIso.sum2nat                  ~> sum_encode
  1291   NatIso.nat2sum                  ~> sum_decode
  1292   NatIso.list2nat                 ~> list_encode
  1293   NatIso.nat2list                 ~> list_decode
  1294   NatIso.set2nat                  ~> set_encode
  1295   NatIso.nat2set                  ~> set_decode
  1296 
  1297   Lemmas:
  1298   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  1299   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  1300   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  1301   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  1302   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  1303   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  1304   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  1305   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  1306   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  1307   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  1308   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  1309   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  1310   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  1311 
  1312 * Sledgehammer:
  1313   - Renamed ATP commands:
  1314     atp_info     ~> sledgehammer running_atps
  1315     atp_kill     ~> sledgehammer kill_atps
  1316     atp_messages ~> sledgehammer messages
  1317     atp_minimize ~> sledgehammer minimize
  1318     print_atps   ~> sledgehammer available_atps
  1319     INCOMPATIBILITY.
  1320   - Added user's manual ("isabelle doc sledgehammer").
  1321   - Added option syntax and "sledgehammer_params" to customize
  1322     Sledgehammer's behavior.  See the manual for details.
  1323   - Modified the Isar proof reconstruction code so that it produces
  1324     direct proofs rather than proofs by contradiction.  (This feature
  1325     is still experimental.)
  1326   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  1327     full-typed mode.
  1328   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  1329 
  1330 * Nitpick:
  1331   - Added and implemented "binary_ints" and "bits" options.
  1332   - Added "std" option and implemented support for nonstandard models.
  1333   - Added and implemented "finitize" option to improve the precision
  1334     of infinite datatypes based on a monotonicity analysis.
  1335   - Added support for quotient types.
  1336   - Added support for "specification" and "ax_specification"
  1337     constructs.
  1338   - Added support for local definitions (for "function" and
  1339     "termination" proofs).
  1340   - Added support for term postprocessors.
  1341   - Optimized "Multiset.multiset" and "FinFun.finfun".
  1342   - Improved efficiency of "destroy_constrs" optimization.
  1343   - Fixed soundness bugs related to "destroy_constrs" optimization and
  1344     record getters.
  1345   - Fixed soundness bug related to higher-order constructors.
  1346   - Fixed soundness bug when "full_descrs" is enabled.
  1347   - Improved precision of set constructs.
  1348   - Added "atoms" option.
  1349   - Added cache to speed up repeated Kodkod invocations on the same
  1350     problems.
  1351   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  1352     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  1353     "SAT4J_Light".  INCOMPATIBILITY.
  1354   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  1355     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  1356   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  1357 
  1358 * Method "induct" now takes instantiations of the form t, where t is not
  1359   a variable, as a shorthand for "x == t", where x is a fresh variable.
  1360   If this is not intended, t has to be enclosed in parentheses.
  1361   By default, the equalities generated by definitional instantiations
  1362   are pre-simplified, which may cause parameters of inductive cases
  1363   to disappear, or may even delete some of the inductive cases.
  1364   Use "induct (no_simp)" instead of "induct" to restore the old
  1365   behaviour. The (no_simp) option is also understood by the "cases"
  1366   and "nominal_induct" methods, which now perform pre-simplification, too.
  1367   INCOMPATIBILITY.
  1368 
  1369 
  1370 *** HOLCF ***
  1371 
  1372 * Variable names in lemmas generated by the domain package have
  1373 changed; the naming scheme is now consistent with the HOL datatype
  1374 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  1375 
  1376 * The domain package no longer defines the function "foo_copy" for
  1377 recursive domain "foo".  The reach lemma is now stated directly in
  1378 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  1379 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  1380 
  1381 * Most definedness lemmas generated by the domain package (previously
  1382 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  1383 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  1384 Proofs that used definedness lemmas as intro rules may break,
  1385 potential INCOMPATIBILITY.
  1386 
  1387 * Induction and casedist rules generated by the domain package now
  1388 declare proper case_names (one called "bottom", and one named for each
  1389 constructor).  INCOMPATIBILITY.
  1390 
  1391 * For mutually-recursive domains, separate "reach" and "take_lemma"
  1392 rules are generated for each domain, INCOMPATIBILITY.
  1393 
  1394   foo_bar.reach       ~> foo.reach  bar.reach
  1395   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  1396 
  1397 * Some lemmas generated by the domain package have been renamed for
  1398 consistency with the datatype package, INCOMPATIBILITY.
  1399 
  1400   foo.ind        ~> foo.induct
  1401   foo.finite_ind ~> foo.finite_induct
  1402   foo.coind      ~> foo.coinduct
  1403   foo.casedist   ~> foo.exhaust
  1404   foo.exhaust    ~> foo.nchotomy
  1405 
  1406 * For consistency with other definition packages, the fixrec package
  1407 now generates qualified theorem names, INCOMPATIBILITY.
  1408 
  1409   foo_simps  ~> foo.simps
  1410   foo_unfold ~> foo.unfold
  1411   foo_induct ~> foo.induct
  1412 
  1413 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  1414 method and internal fixrec proofs now use the default simpset instead.
  1415 INCOMPATIBILITY.
  1416 
  1417 * The "contlub" predicate has been removed.  Proof scripts should use
  1418 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  1419 
  1420 * The "admw" predicate has been removed, INCOMPATIBILITY.
  1421 
  1422 * The constants cpair, cfst, and csnd have been removed in favor of
  1423 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  1424 
  1425 
  1426 *** ML ***
  1427 
  1428 * Antiquotations for basic formal entities:
  1429 
  1430     @{class NAME}         -- type class
  1431     @{class_syntax NAME}  -- syntax representation of the above
  1432 
  1433     @{type_name NAME}     -- logical type
  1434     @{type_abbrev NAME}   -- type abbreviation
  1435     @{nonterminal NAME}   -- type of concrete syntactic category
  1436     @{type_syntax NAME}   -- syntax representation of any of the above
  1437 
  1438     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  1439     @{const_abbrev NAME}  -- abbreviated constant
  1440     @{const_syntax NAME}  -- syntax representation of any of the above
  1441 
  1442 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  1443 syntax constant (cf. 'syntax' command).
  1444 
  1445 * Antiquotation @{make_string} inlines a function to print arbitrary
  1446 values similar to the ML toplevel.  The result is compiler dependent
  1447 and may fall back on "?" in certain situations.
  1448 
  1449 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  1450 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  1451 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  1452 not work with the asynchronous Isar document model.
  1453 
  1454 * Configuration options now admit dynamic default values, depending on
  1455 the context or even global references.
  1456 
  1457 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  1458 uses an efficient external library if available (for Poly/ML).
  1459 
  1460 * Renamed some important ML structures, while keeping the old names
  1461 for some time as aliases within the structure Legacy:
  1462 
  1463   OuterKeyword  ~>  Keyword
  1464   OuterLex      ~>  Token
  1465   OuterParse    ~>  Parse
  1466   OuterSyntax   ~>  Outer_Syntax
  1467   PrintMode     ~>  Print_Mode
  1468   SpecParse     ~>  Parse_Spec
  1469   ThyInfo       ~>  Thy_Info
  1470   ThyLoad       ~>  Thy_Load
  1471   ThyOutput     ~>  Thy_Output
  1472   TypeInfer     ~>  Type_Infer
  1473 
  1474 Note that "open Legacy" simplifies porting of sources, but forgetting
  1475 to remove it again will complicate porting again in the future.
  1476 
  1477 * Most operations that refer to a global context are named
  1478 accordingly, e.g. Simplifier.global_context or
  1479 ProofContext.init_global.  There are some situations where a global
  1480 context actually works, but under normal circumstances one needs to
  1481 pass the proper local context through the code!
  1482 
  1483 * Discontinued old TheoryDataFun with its copy/init operation -- data
  1484 needs to be pure.  Functor Theory_Data_PP retains the traditional
  1485 Pretty.pp argument to merge, which is absent in the standard
  1486 Theory_Data version.
  1487 
  1488 * Sorts.certify_sort and derived "cert" operations for types and terms
  1489 no longer minimize sorts.  Thus certification at the boundary of the
  1490 inference kernel becomes invariant under addition of class relations,
  1491 which is an important monotonicity principle.  Sorts are now minimized
  1492 in the syntax layer only, at the boundary between the end-user and the
  1493 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  1494 explicitly in rare situations.
  1495 
  1496 * Renamed old-style Drule.standard to Drule.export_without_context, to
  1497 emphasize that this is in no way a standard operation.
  1498 INCOMPATIBILITY.
  1499 
  1500 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  1501 usual for resolution.  Rare INCOMPATIBILITY.
  1502 
  1503 * Renamed varify/unvarify operations to varify_global/unvarify_global
  1504 to emphasize that these only work in a global situation (which is
  1505 quite rare).
  1506 
  1507 * Curried take and drop in library.ML; negative length is interpreted
  1508 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  1509 
  1510 * Proof terms: type substitutions on proof constants now use canonical
  1511 order of type variables.  INCOMPATIBILITY for tools working with proof
  1512 terms.
  1513 
  1514 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  1515 may no longer carry premises.  User-level specifications are
  1516 transformed accordingly by Thm.add_axiom/add_def.
  1517 
  1518 
  1519 *** System ***
  1520 
  1521 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  1522 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  1523 proof terms are enabled unconditionally in the new HOL-Proofs image.
  1524 
  1525 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  1526 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  1527 respectively.
  1528 
  1529 * Old lib/scripts/polyml-platform is superseded by the
  1530 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  1531 variant, even on a 64 bit machine.  The following example setting
  1532 prefers 64 bit if available:
  1533 
  1534   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  1535 
  1536 * The preliminary Isabelle/jEdit application demonstrates the emerging
  1537 Isabelle/Scala layer for advanced prover interaction and integration.
  1538 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  1539 component.
  1540 
  1541 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  1542 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  1543 similar to the default assignment of the document preparation system
  1544 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  1545 provides some operations for direct access to the font without asking
  1546 the user for manual installation.
  1547 
  1548 
  1549 
  1550 New in Isabelle2009-1 (December 2009)
  1551 -------------------------------------
  1552 
  1553 *** General ***
  1554 
  1555 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  1556 one backslash should be used, even in ML sources.
  1557 
  1558 
  1559 *** Pure ***
  1560 
  1561 * Locale interpretation propagates mixins along the locale hierarchy.
  1562 The currently only available mixins are the equations used to map
  1563 local definitions to terms of the target domain of an interpretation.
  1564 
  1565 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  1566 loc" to print all interpretations of locale "loc" in the theory.
  1567 Interpretations in proofs are not shown.
  1568 
  1569 * Thoroughly revised locales tutorial.  New section on conditional
  1570 interpretation.
  1571 
  1572 * On instantiation of classes, remaining undefined class parameters
  1573 are formally declared.  INCOMPATIBILITY.
  1574 
  1575 
  1576 *** Document preparation ***
  1577 
  1578 * New generalized style concept for printing terms: @{foo (style) ...}
  1579 instead of @{foo_style style ...}  (old form is still retained for
  1580 backward compatibility).  Styles can be also applied for
  1581 antiquotations prop, term_type and typeof.
  1582 
  1583 
  1584 *** HOL ***
  1585 
  1586 * New proof method "smt" for a combination of first-order logic with
  1587 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  1588 fixed-size bitvectors; there is also basic support for higher-order
  1589 features (esp. lambda abstractions).  It is an incomplete decision
  1590 procedure based on external SMT solvers using the oracle mechanism;
  1591 for the SMT solver Z3, this method is proof-producing.  Certificates
  1592 are provided to avoid calling the external solvers solely for
  1593 re-checking proofs.  Due to a remote SMT service there is no need for
  1594 installing SMT solvers locally.  See src/HOL/SMT.
  1595 
  1596 * New commands to load and prove verification conditions generated by
  1597 the Boogie program verifier or derived systems (e.g. the Verifying C
  1598 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1599 
  1600 * New counterexample generator tool 'nitpick' based on the Kodkod
  1601 relational model finder.  See src/HOL/Tools/Nitpick and
  1602 src/HOL/Nitpick_Examples.
  1603 
  1604 * New commands 'code_pred' and 'values' to invoke the predicate
  1605 compiler and to enumerate values of inductive predicates.
  1606 
  1607 * A tabled implementation of the reflexive transitive closure.
  1608 
  1609 * New implementation of quickcheck uses generic code generator;
  1610 default generators are provided for all suitable HOL types, records
  1611 and datatypes.  Old quickcheck can be re-activated importing theory
  1612 Library/SML_Quickcheck.
  1613 
  1614 * New testing tool Mirabelle for automated proof tools.  Applies
  1615 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1616 every proof step in a theory.  To be used in batch mode via the
  1617 "mirabelle" utility.
  1618 
  1619 * New proof method "sos" (sum of squares) for nonlinear real
  1620 arithmetic (originally due to John Harison). It requires theory
  1621 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1622 works well in practice on quantifier-free real arithmetic with +, -,
  1623 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1624 inequalities between polynomials.  It makes use of external
  1625 semidefinite programming solvers.  Method "sos" generates a
  1626 certificate that can be pasted into the proof thus avoiding the need
  1627 to call an external tool every time the proof is checked.  See
  1628 src/HOL/Library/Sum_Of_Squares.
  1629 
  1630 * New method "linarith" invokes existing linear arithmetic decision
  1631 procedure only.
  1632 
  1633 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1634 
  1635 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1636 Causes full type information to be output to the ATPs.  This slows
  1637 ATPs down considerably but eliminates a source of unsound "proofs"
  1638 that fail later.
  1639 
  1640 * New method "metisFT": A version of metis that uses full type
  1641 information in order to avoid failures of proof reconstruction.
  1642 
  1643 * New evaluator "approximate" approximates an real valued term using
  1644 the same method as the approximation method.
  1645 
  1646 * Method "approximate" now supports arithmetic expressions as
  1647 boundaries of intervals and implements interval splitting and Taylor
  1648 series expansion.
  1649 
  1650 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1651 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1652 
  1653 * New theory SupInf of the supremum and infimum operators for sets of
  1654 reals.
  1655 
  1656 * New theory Probability, which contains a development of measure
  1657 theory, eventually leading to Lebesgue integration and probability.
  1658 
  1659 * Extended Multivariate Analysis to include derivation and Brouwer's
  1660 fixpoint theorem.
  1661 
  1662 * Reorganization of number theory, INCOMPATIBILITY:
  1663   - new number theory development for nat and int, in theories Divides
  1664     and GCD as well as in new session Number_Theory
  1665   - some constants and facts now suffixed with _nat and _int
  1666     accordingly
  1667   - former session NumberTheory now named Old_Number_Theory, including
  1668     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1669   - moved theory Pocklington from src/HOL/Library to
  1670     src/HOL/Old_Number_Theory
  1671 
  1672 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1673 lcm of finite and infinite sets. It is shown that they form a complete
  1674 lattice.
  1675 
  1676 * Class semiring_div requires superclass no_zero_divisors and proof of
  1677 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1678 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1679 generalized to class semiring_div, subsuming former theorems
  1680 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1681 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1682 INCOMPATIBILITY.
  1683 
  1684 * Refinements to lattice classes and sets:
  1685   - less default intro/elim rules in locale variant, more default
  1686     intro/elim rules in class variant: more uniformity
  1687   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1688     le_inf_iff
  1689   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1690     sup_aci)
  1691   - renamed ACI to inf_sup_aci
  1692   - new class "boolean_algebra"
  1693   - class "complete_lattice" moved to separate theory
  1694     "Complete_Lattice"; corresponding constants (and abbreviations)
  1695     renamed and with authentic syntax:
  1696     Set.Inf ~>    Complete_Lattice.Inf
  1697     Set.Sup ~>    Complete_Lattice.Sup
  1698     Set.INFI ~>   Complete_Lattice.INFI
  1699     Set.SUPR ~>   Complete_Lattice.SUPR
  1700     Set.Inter ~>  Complete_Lattice.Inter
  1701     Set.Union ~>  Complete_Lattice.Union
  1702     Set.INTER ~>  Complete_Lattice.INTER
  1703     Set.UNION ~>  Complete_Lattice.UNION
  1704   - authentic syntax for
  1705     Set.Pow
  1706     Set.image
  1707   - mere abbreviations:
  1708     Set.empty               (for bot)
  1709     Set.UNIV                (for top)
  1710     Set.inter               (for inf, formerly Set.Int)
  1711     Set.union               (for sup, formerly Set.Un)
  1712     Complete_Lattice.Inter  (for Inf)
  1713     Complete_Lattice.Union  (for Sup)
  1714     Complete_Lattice.INTER  (for INFI)
  1715     Complete_Lattice.UNION  (for SUPR)
  1716   - object-logic definitions as far as appropriate
  1717 
  1718 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1719 Un_subset_iff are explicitly deleted as default simp rules; then also
  1720 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1721 deleted to achieve the desired effect.
  1722 
  1723 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1724 rules by default any longer; the same applies to min_max.inf_absorb1
  1725 etc.  INCOMPATIBILITY.
  1726 
  1727 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1728 pred_set_conv by default.  INCOMPATIBILITY.
  1729 
  1730 * Power operations on relations and functions are now one dedicated
  1731 constant "compow" with infix syntax "^^".  Power operation on
  1732 multiplicative monoids retains syntax "^" and is now defined generic
  1733 in class power.  INCOMPATIBILITY.
  1734 
  1735 * Relation composition "R O S" now has a more standard argument order:
  1736 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1737 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1738 break, since the O_assoc rule was not rewritten like this.  Fix using
  1739 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1740 
  1741 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1742 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1743 INCOMPATIBILITY.
  1744 
  1745 * Most rules produced by inductive and datatype package have mandatory
  1746 prefixes.  INCOMPATIBILITY.
  1747 
  1748 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1749 the attribute of the same name.  Each of the theorems in the list
  1750 DERIV_intros assumes composition with an additional function and
  1751 matches a variable to the derivative, which has to be solved by the
  1752 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1753 of most elementary terms.  Former Maclauren.DERIV_tac and
  1754 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1755 INCOMPATIBILITY.
  1756 
  1757 * Code generator attributes follow the usual underscore convention:
  1758     code_unfold     replaces    code unfold
  1759     code_post       replaces    code post
  1760     etc.
  1761   INCOMPATIBILITY.
  1762 
  1763 * Renamed methods:
  1764     sizechange -> size_change
  1765     induct_scheme -> induction_schema
  1766   INCOMPATIBILITY.
  1767 
  1768 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1769 INCOMPATIBILITY, use "undefined" directly.
  1770 
  1771 * Renamed theorems:
  1772     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1773     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1774     Suc_plus1 -> Suc_eq_plus1
  1775     *anti_sym -> *antisym*
  1776     vector_less_eq_def -> vector_le_def
  1777   INCOMPATIBILITY.
  1778 
  1779 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1780 INCOMPATIBILITY.
  1781 
  1782 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1783 INCOMPATIBILITY.
  1784 
  1785 
  1786 *** HOLCF ***
  1787 
  1788 * Theory Representable defines a class "rep" of domains that are
  1789 representable (via an ep-pair) in the universal domain type "udom".
  1790 Instances are provided for all type constructors defined in HOLCF.
  1791 
  1792 * The 'new_domain' command is a purely definitional version of the
  1793 domain package, for representable domains.  Syntax is identical to the
  1794 old domain package.  The 'new_domain' package also supports indirect
  1795 recursion using previously-defined type constructors.  See
  1796 src/HOLCF/ex/New_Domain.thy for examples.
  1797 
  1798 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1799 on the left-hand side of an equation, and then performs
  1800 simplification.  Rewriting is done using rules declared with the
  1801 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1802 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1803 
  1804 * The pattern-match compiler in 'fixrec' can now handle constructors
  1805 with HOL function types.  Pattern-match combinators for the Pair
  1806 constructor are pre-configured.
  1807 
  1808 * The 'fixrec' package now produces better fixed-point induction rules
  1809 for mutually-recursive definitions:  Induction rules have conclusions
  1810 of the form "P foo bar" instead of "P <foo, bar>".
  1811 
  1812 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1813 been renamed to "below".  The name "below" now replaces "less" in many
  1814 theorem names.  (Legacy theorem names using "less" are still supported
  1815 as well.)
  1816 
  1817 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1818 patterns can be used to generate strictness rules, or to make
  1819 functions more strict (much like the bang-patterns supported by the
  1820 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1821 examples.
  1822 
  1823 
  1824 *** ML ***
  1825 
  1826 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1827 errors and run-time exceptions, including detailed source positions.
  1828 
  1829 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1830 identified entries, with some additional information such as source
  1831 position, logical grouping etc.
  1832 
  1833 * Theory and context data is now introduced by the simplified and
  1834 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1835 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1836 copy operation) is still available for some time.
  1837 
  1838 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1839 provides a high-level programming interface to synchronized state
  1840 variables with atomic update.  This works via pure function
  1841 application within a critical section -- its runtime should be as
  1842 short as possible; beware of deadlocks if critical code is nested,
  1843 either directly or indirectly via other synchronized variables!
  1844 
  1845 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1846 wraps raw ML references, explicitly indicating their non-thread-safe
  1847 behaviour.  The Isar toplevel keeps this structure open, to
  1848 accommodate Proof General as well as quick and dirty interactive
  1849 experiments with references.
  1850 
  1851 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1852 parallel tactical reasoning.
  1853 
  1854 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1855 are similar to SUBPROOF, but are slightly more flexible: only the
  1856 specified parts of the subgoal are imported into the context, and the
  1857 body tactic may introduce new subgoals and schematic variables.
  1858 
  1859 * Old tactical METAHYPS, which does not observe the proof context, has
  1860 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1861 or Subgoal.FOCUS etc.
  1862 
  1863 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  1864 functors have their own ML name space there is no point to mark them
  1865 separately.)  Minor INCOMPATIBILITY.
  1866 
  1867 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  1868 
  1869 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  1870 INCOMPATIBILITY.
  1871 
  1872 * Operations of structure Skip_Proof no longer require quick_and_dirty
  1873 mode, which avoids critical setmp.
  1874 
  1875 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  1876 combinators for "args".  INCOMPATIBILITY, need to use simplified
  1877 Attrib/Method.setup introduced in Isabelle2009.
  1878 
  1879 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  1880 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  1881 last resort.  INCOMPATIBILITY.
  1882 
  1883 * Display.pretty_thm now requires a proper context (cf. former
  1884 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  1885 or even Display.pretty_thm_without_context as last resort.
  1886 INCOMPATIBILITY.
  1887 
  1888 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  1889 Syntax.pretty_typ/term directly, preferably with proper context
  1890 instead of global theory.
  1891 
  1892 
  1893 *** System ***
  1894 
  1895 * Further fine tuning of parallel proof checking, scales up to 8 cores
  1896 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  1897 usedir option -q.
  1898 
  1899 * Support for additional "Isabelle components" via etc/components, see
  1900 also the system manual.
  1901 
  1902 * The isabelle makeall tool now operates on all components with
  1903 IsaMakefile, not just hardwired "logics".
  1904 
  1905 * Removed "compress" option from isabelle-process and isabelle usedir;
  1906 this is always enabled.
  1907 
  1908 * Discontinued support for Poly/ML 4.x versions.
  1909 
  1910 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  1911 on a given logic image.  This requires the lighttpd webserver and is
  1912 currently supported on Linux only.
  1913 
  1914 
  1915 
  1916 New in Isabelle2009 (April 2009)
  1917 --------------------------------
  1918 
  1919 *** General ***
  1920 
  1921 * Simplified main Isabelle executables, with less surprises on
  1922 case-insensitive file-systems (such as Mac OS).
  1923 
  1924   - The main Isabelle tool wrapper is now called "isabelle" instead of
  1925     "isatool."
  1926 
  1927   - The former "isabelle" alias for "isabelle-process" has been
  1928     removed (should rarely occur to regular users).
  1929 
  1930   - The former "isabelle-interface" and its alias "Isabelle" have been
  1931     removed (interfaces are now regular Isabelle tools).
  1932 
  1933 Within scripts and make files, the Isabelle environment variables
  1934 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  1935 respectively.  (The latter are still available as legacy feature.)
  1936 
  1937 The old isabelle-interface wrapper could react in confusing ways if
  1938 the interface was uninstalled or changed otherwise.  Individual
  1939 interface tool configuration is now more explicit, see also the
  1940 Isabelle system manual.  In particular, Proof General is now available
  1941 via "isabelle emacs".
  1942 
  1943 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  1944 purge installed copies of Isabelle executables and re-run "isabelle
  1945 install -p ...", or use symlinks.
  1946 
  1947 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  1948 old ~/isabelle, which was slightly non-standard and apt to cause
  1949 surprises on case-insensitive file-systems (such as Mac OS).
  1950 
  1951 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  1952 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  1953 care is required when using older releases of Isabelle.  Note that
  1954 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  1955 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  1956 
  1957 * Proofs of fully specified statements are run in parallel on
  1958 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  1959 a regular 4-core machine, if the initial heap space is made reasonably
  1960 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  1961 
  1962 * The main reference manuals ("isar-ref", "implementation", and
  1963 "system") have been updated and extended.  Formally checked references
  1964 as hyperlinks are now available uniformly.
  1965 
  1966 
  1967 *** Pure ***
  1968 
  1969 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  1970 respects.  The most important changes are listed below.  See the
  1971 Tutorial on Locales ("locales" manual) for details.
  1972 
  1973 - In locale expressions, instantiation replaces renaming.  Parameters
  1974 must be declared in a for clause.  To aid compatibility with previous
  1975 parameter inheritance, in locale declarations, parameters that are not
  1976 'touched' (instantiation position "_" or omitted) are implicitly added
  1977 with their syntax at the beginning of the for clause.
  1978 
  1979 - Syntax from abbreviations and definitions in locales is available in
  1980 locale expressions and context elements.  The latter is particularly
  1981 useful in locale declarations.
  1982 
  1983 - More flexible mechanisms to qualify names generated by locale
  1984 expressions.  Qualifiers (prefixes) may be specified in locale
  1985 expressions, and can be marked as mandatory (syntax: "name!:") or
  1986 optional (syntax "name?:").  The default depends for plain "name:"
  1987 depends on the situation where a locale expression is used: in
  1988 commands 'locale' and 'sublocale' prefixes are optional, in
  1989 'interpretation' and 'interpret' prefixes are mandatory.  The old
  1990 implicit qualifiers derived from the parameter names of a locale are
  1991 no longer generated.
  1992 
  1993 - Command "sublocale l < e" replaces "interpretation l < e".  The
  1994 instantiation clause in "interpretation" and "interpret" (square
  1995 brackets) is no longer available.  Use locale expressions.
  1996 
  1997 - When converting proof scripts, mandatory qualifiers in
  1998 'interpretation' and 'interpret' should be retained by default, even
  1999 if this is an INCOMPATIBILITY compared to former behavior.  In the
  2000 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  2001 in locale expressions range over a single locale instance only.
  2002 
  2003 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  2004 In existing theorem specifications replace the includes element by the
  2005 respective context elements of the included locale, omitting those
  2006 that are already present in the theorem specification.  Multiple
  2007 assume elements of a locale should be replaced by a single one
  2008 involving the locale predicate.  In the proof body, declarations (most
  2009 notably theorems) may be regained by interpreting the respective
  2010 locales in the proof context as required (command "interpret").
  2011 
  2012 If using "includes" in replacement of a target solely because the
  2013 parameter types in the theorem are not as general as in the target,
  2014 consider declaring a new locale with additional type constraints on
  2015 the parameters (context element "constrains").
  2016 
  2017 - Discontinued "locale (open)".  INCOMPATIBILITY.
  2018 
  2019 - Locale interpretation commands no longer attempt to simplify goal.
  2020 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  2021 methods intro_locales and unfold_locales to clarify.
  2022 
  2023 - Locale interpretation commands no longer accept interpretation
  2024 attributes.  INCOMPATIBILITY.
  2025 
  2026 * Class declaration: so-called "base sort" must not be given in import
  2027 list any longer, but is inferred from the specification.  Particularly
  2028 in HOL, write
  2029 
  2030     class foo = ...
  2031 
  2032 instead of
  2033 
  2034     class foo = type + ...
  2035 
  2036 * Class target: global versions of theorems stemming do not carry a
  2037 parameter prefix any longer.  INCOMPATIBILITY.
  2038 
  2039 * Class 'instance' command no longer accepts attached definitions.
  2040 INCOMPATIBILITY, use proper 'instantiation' target instead.
  2041 
  2042 * Recovered hiding of consts, which was accidentally broken in
  2043 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  2044 makes c inaccessible; consider using ``hide (open) const c'' instead.
  2045 
  2046 * Slightly more coherent Pure syntax, with updated documentation in
  2047 isar-ref manual.  Removed locales meta_term_syntax and
  2048 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  2049 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  2050 directly in regular applications.
  2051 
  2052 * There is a new syntactic category "float_const" for signed decimal
  2053 fractions (e.g. 123.45 or -123.45).
  2054 
  2055 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  2056 interface with 'setup' command instead.
  2057 
  2058 * Command 'local_setup' is similar to 'setup', but operates on a local
  2059 theory context.
  2060 
  2061 * The 'axiomatization' command now only works within a global theory
  2062 context.  INCOMPATIBILITY.
  2063 
  2064 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  2065 hypotheses.  Sorts required in the course of reasoning need to be
  2066 covered by the constraints in the initial statement, completed by the
  2067 type instance information of the background theory.  Non-trivial sort
  2068 hypotheses, which rarely occur in practice, may be specified via
  2069 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  2070 
  2071   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  2072 
  2073 The result contains an implicit sort hypotheses as before --
  2074 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  2075 normalization.
  2076 
  2077 * Generalized Isar history, with support for linear undo, direct state
  2078 addressing etc.
  2079 
  2080 * Changed defaults for unify configuration options:
  2081 
  2082   unify_trace_bound = 50 (formerly 25)
  2083   unify_search_bound = 60 (formerly 30)
  2084 
  2085 * Different bookkeeping for code equations (INCOMPATIBILITY):
  2086 
  2087   a) On theory merge, the last set of code equations for a particular
  2088      constant is taken (in accordance with the policy applied by other
  2089      parts of the code generator framework).
  2090 
  2091   b) Code equations stemming from explicit declarations (e.g. code
  2092      attribute) gain priority over default code equations stemming
  2093      from definition, primrec, fun etc.
  2094 
  2095 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  2096 
  2097 * Unified theorem tables for both code generators.  Thus [code
  2098 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  2099 
  2100 * Command 'find_consts' searches for constants based on type and name
  2101 patterns, e.g.
  2102 
  2103     find_consts "_ => bool"
  2104 
  2105 By default, matching is against subtypes, but it may be restricted to
  2106 the whole type.  Searching by name is possible.  Multiple queries are
  2107 conjunctive and queries may be negated by prefixing them with a
  2108 hyphen:
  2109 
  2110     find_consts strict: "_ => bool" name: "Int" -"int => int"
  2111 
  2112 * New 'find_theorems' criterion "solves" matches theorems that
  2113 directly solve the current goal (modulo higher-order unification).
  2114 
  2115 * Auto solve feature for main theorem statements: whenever a new goal
  2116 is stated, "find_theorems solves" is called; any theorems that could
  2117 solve the lemma directly are listed as part of the goal state.
  2118 Cf. associated options in Proof General Isabelle settings menu,
  2119 enabled by default, with reasonable timeout for pathological cases of
  2120 higher-order unification.
  2121 
  2122 
  2123 *** Document preparation ***
  2124 
  2125 * Antiquotation @{lemma} now imitates a regular terminal proof,
  2126 demanding keyword 'by' and supporting the full method expression
  2127 syntax just like the Isar command 'by'.
  2128 
  2129 
  2130 *** HOL ***
  2131 
  2132 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  2133 points Main and Complex_Main remain as before.
  2134 
  2135 * Logic image HOL-Plain provides a minimal HOL with the most important
  2136 tools available (inductive, datatype, primrec, ...).  This facilitates
  2137 experimentation and tool development.  Note that user applications
  2138 (and library theories) should never refer to anything below theory
  2139 Main, as before.
  2140 
  2141 * Logic image HOL-Main stops at theory Main, and thus facilitates
  2142 experimentation due to shorter build times.
  2143 
  2144 * Logic image HOL-NSA contains theories of nonstandard analysis which
  2145 were previously part of former HOL-Complex.  Entry point Hyperreal
  2146 remains valid, but theories formerly using Complex_Main should now use
  2147 new entry point Hypercomplex.
  2148 
  2149 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  2150 Posix processes.  Avoids potentially expensive forking of the ML
  2151 process.  New thread-based implementation also works on non-Unix
  2152 platforms (Cygwin).  Provers are no longer hardwired, but defined
  2153 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  2154 commands are covered in the isar-ref manual.
  2155 
  2156 * Wrapper scripts for remote SystemOnTPTP service allows to use
  2157 sledgehammer without local ATP installation (Vampire etc.). Other
  2158 provers may be included via suitable ML wrappers, see also
  2159 src/HOL/ATP_Linkup.thy.
  2160 
  2161 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  2162 menu.
  2163 
  2164 * The metis method no longer fails because the theorem is too trivial
  2165 (contains the empty clause).
  2166 
  2167 * The metis method now fails in the usual manner, rather than raising
  2168 an exception, if it determines that it cannot prove the theorem.
  2169 
  2170 * Method "coherent" implements a prover for coherent logic (see also
  2171 src/Tools/coherent.ML).
  2172 
  2173 * Constants "undefined" and "default" replace "arbitrary".  Usually
  2174 "undefined" is the right choice to replace "arbitrary", though
  2175 logically there is no difference.  INCOMPATIBILITY.
  2176 
  2177 * Command "value" now integrates different evaluation mechanisms.  The
  2178 result of the first successful evaluation mechanism is printed.  In
  2179 square brackets a particular named evaluation mechanisms may be
  2180 specified (currently, [SML], [code] or [nbe]).  See further
  2181 src/HOL/ex/Eval_Examples.thy.
  2182 
  2183 * Normalization by evaluation now allows non-leftlinear equations.
  2184 Declare with attribute [code nbe].
  2185 
  2186 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  2187 as the structured Isar versions "cases" and "induct", cf. the
  2188 corresponding "cases" and "induct" attributes.  Mutual induction rules
  2189 are now presented as a list of individual projections
  2190 (e.g. foo_bar.inducts for types foo and bar); the old format with
  2191 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  2192 rare situations a different rule is selected --- notably nested tuple
  2193 elimination instead of former prod.exhaust: use explicit (case_tac t
  2194 rule: prod.exhaust) here.
  2195 
  2196 * Attributes "cases", "induct", "coinduct" support "del" option.
  2197 
  2198 * Removed fact "case_split_thm", which duplicates "case_split".
  2199 
  2200 * The option datatype has been moved to a new theory Option.  Renamed
  2201 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  2202 
  2203 * New predicate "strict_mono" classifies strict functions on partial
  2204 orders.  With strict functions on linear orders, reasoning about
  2205 (in)equalities is facilitated by theorems "strict_mono_eq",
  2206 "strict_mono_less_eq" and "strict_mono_less".
  2207 
  2208 * Some set operations are now proper qualified constants with
  2209 authentic syntax.  INCOMPATIBILITY:
  2210 
  2211     op Int ~>   Set.Int
  2212     op Un ~>    Set.Un
  2213     INTER ~>    Set.INTER
  2214     UNION ~>    Set.UNION
  2215     Inter ~>    Set.Inter
  2216     Union ~>    Set.Union
  2217     {} ~>       Set.empty
  2218     UNIV ~>     Set.UNIV
  2219 
  2220 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  2221 theory Set.
  2222 
  2223 * Auxiliary class "itself" has disappeared -- classes without any
  2224 parameter are treated as expected by the 'class' command.
  2225 
  2226 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  2227 
  2228 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  2229 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  2230 
  2231 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  2232 method "approximation".  It proves formulas on real values by using
  2233 interval arithmetic.  In the formulas are also the transcendental
  2234 functions sin, cos, tan, atan, ln, exp and the constant pi are
  2235 allowed. For examples see
  2236 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  2237 
  2238 * Theory "Reflection" now resides in HOL/Library.
  2239 
  2240 * Entry point to Word library now simply named "Word".
  2241 INCOMPATIBILITY.
  2242 
  2243 * Made source layout more coherent with logical distribution
  2244 structure:
  2245 
  2246     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  2247     src/HOL/Library/Code_Message.thy ~> src/HOL/
  2248     src/HOL/Library/GCD.thy ~> src/HOL/
  2249     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  2250     src/HOL/Library/Parity.thy ~> src/HOL/
  2251     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  2252     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  2253     src/HOL/Real/Lubs.thy ~> src/HOL/
  2254     src/HOL/Real/PReal.thy ~> src/HOL/
  2255     src/HOL/Real/Rational.thy ~> src/HOL/
  2256     src/HOL/Real/RComplete.thy ~> src/HOL/
  2257     src/HOL/Real/RealDef.thy ~> src/HOL/
  2258     src/HOL/Real/RealPow.thy ~> src/HOL/
  2259     src/HOL/Real/Real.thy ~> src/HOL/
  2260     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  2261     src/HOL/Complex/Complex.thy ~> src/HOL/
  2262     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  2263     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  2264     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  2265     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  2266     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  2267     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  2268     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  2269     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  2270     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  2271     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  2272     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  2273     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  2274     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  2275     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  2276     src/HOL/Real/Float ~> src/HOL/Library/
  2277     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  2278     src/HOL/Real/RealVector.thy ~> src/HOL/
  2279 
  2280     src/HOL/arith_data.ML ~> src/HOL/Tools
  2281     src/HOL/hologic.ML ~> src/HOL/Tools
  2282     src/HOL/simpdata.ML ~> src/HOL/Tools
  2283     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  2284     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  2285     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  2286     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  2287     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  2288     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  2289     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  2290 
  2291     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  2292     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  2293     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  2294     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  2295     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  2296     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  2297 
  2298 * If methods "eval" and "evaluation" encounter a structured proof
  2299 state with !!/==>, only the conclusion is evaluated to True (if
  2300 possible), avoiding strange error messages.
  2301 
  2302 * Method "sizechange" automates termination proofs using (a
  2303 modification of) the size-change principle.  Requires SAT solver.  See
  2304 src/HOL/ex/Termination.thy for examples.
  2305 
  2306 * Simplifier: simproc for let expressions now unfolds if bound
  2307 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  2308 
  2309 * Method "arith": Linear arithmetic now ignores all inequalities when
  2310 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  2311 
  2312 * New attribute "arith" for facts that should always be used
  2313 automatically by arithmetic. It is intended to be used locally in
  2314 proofs, e.g.
  2315 
  2316   assumes [arith]: "x > 0"
  2317 
  2318 Global usage is discouraged because of possible performance impact.
  2319 
  2320 * New classes "top" and "bot" with corresponding operations "top" and
  2321 "bot" in theory Orderings; instantiation of class "complete_lattice"
  2322 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  2323 
  2324 * Changed definition lemma "less_fun_def" in order to provide an
  2325 instance for preorders on functions; use lemma "less_le" instead.
  2326 INCOMPATIBILITY.
  2327 
  2328 * Theory Orderings: class "wellorder" moved here, with explicit
  2329 induction rule "less_induct" as assumption.  For instantiation of
  2330 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  2331 INCOMPATIBILITY.
  2332 
  2333 * Theory Orderings: added class "preorder" as superclass of "order".
  2334 INCOMPATIBILITY: Instantiation proofs for order, linorder
  2335 etc. slightly changed.  Some theorems named order_class.* now named
  2336 preorder_class.*.
  2337 
  2338 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  2339 "diag" to "Id_on".
  2340 
  2341 * Theory Finite_Set: added a new fold combinator of type
  2342 
  2343   ('a => 'b => 'b) => 'b => 'a set => 'b
  2344 
  2345 Occasionally this is more convenient than the old fold combinator
  2346 which is now defined in terms of the new one and renamed to
  2347 fold_image.
  2348 
  2349 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  2350 and "ring_simps" have been replaced by "algebra_simps" (which can be
  2351 extended with further lemmas!).  At the moment both still exist but
  2352 the former will disappear at some point.
  2353 
  2354 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  2355 class recpower.  Type-specific simp rules for various recpower types
  2356 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  2357 
  2358 rat_power_0    -> power_0
  2359 rat_power_Suc  -> power_Suc
  2360 realpow_0      -> power_0
  2361 realpow_Suc    -> power_Suc
  2362 complexpow_0   -> power_0
  2363 complexpow_Suc -> power_Suc
  2364 power_poly_0   -> power_0
  2365 power_poly_Suc -> power_Suc
  2366 
  2367 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  2368 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  2369 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  2370 of lemmas from Divides has been generalized from nat to class
  2371 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  2372 renames resulting from duplicate elimination:
  2373 
  2374     dvd_def_mod ~>          dvd_eq_mod_eq_0
  2375     zero_dvd_iff ~>         dvd_0_left_iff
  2376     dvd_0 ~>                dvd_0_right
  2377     DIVISION_BY_ZERO_DIV ~> div_by_0
  2378     DIVISION_BY_ZERO_MOD ~> mod_by_0
  2379     mult_div ~>             div_mult_self2_is_id
  2380     mult_mod ~>             mod_mult_self2_is_0
  2381 
  2382 * Theory IntDiv: removed many lemmas that are instances of class-based
  2383 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  2384 rename old lemmas as follows:
  2385 
  2386 dvd_diff               -> nat_dvd_diff
  2387 dvd_zminus_iff         -> dvd_minus_iff
  2388 mod_add1_eq            -> mod_add_eq
  2389 mod_mult1_eq           -> mod_mult_right_eq
  2390 mod_mult1_eq'          -> mod_mult_left_eq
  2391 mod_mult_distrib_mod   -> mod_mult_eq
  2392 nat_mod_add_left_eq    -> mod_add_left_eq
  2393 nat_mod_add_right_eq   -> mod_add_right_eq
  2394 nat_mod_div_trivial    -> mod_div_trivial
  2395 nat_mod_mod_trivial    -> mod_mod_trivial
  2396 zdiv_zadd_self1        -> div_add_self1
  2397 zdiv_zadd_self2        -> div_add_self2
  2398 zdiv_zmult_self1       -> div_mult_self2_is_id
  2399 zdiv_zmult_self2       -> div_mult_self1_is_id
  2400 zdvd_triv_left         -> dvd_triv_left
  2401 zdvd_triv_right        -> dvd_triv_right
  2402 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  2403 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  2404 zmod_zadd_left_eq      -> mod_add_left_eq
  2405 zmod_zadd_right_eq     -> mod_add_right_eq
  2406 zmod_zadd_self1        -> mod_add_self1
  2407 zmod_zadd_self2        -> mod_add_self2
  2408 zmod_zadd1_eq          -> mod_add_eq
  2409 zmod_zdiff1_eq         -> mod_diff_eq
  2410 zmod_zdvd_zmod         -> mod_mod_cancel
  2411 zmod_zmod_cancel       -> mod_mod_cancel
  2412 zmod_zmult_self1       -> mod_mult_self2_is_0
  2413 zmod_zmult_self2       -> mod_mult_self1_is_0
  2414 zmod_1                 -> mod_by_1
  2415 zdiv_1                 -> div_by_1
  2416 zdvd_abs1              -> abs_dvd_iff
  2417 zdvd_abs2              -> dvd_abs_iff
  2418 zdvd_refl              -> dvd_refl
  2419 zdvd_trans             -> dvd_trans
  2420 zdvd_zadd              -> dvd_add
  2421 zdvd_zdiff             -> dvd_diff
  2422 zdvd_zminus_iff        -> dvd_minus_iff
  2423 zdvd_zminus2_iff       -> minus_dvd_iff
  2424 zdvd_zmultD            -> dvd_mult_right
  2425 zdvd_zmultD2           -> dvd_mult_left
  2426 zdvd_zmult_mono        -> mult_dvd_mono
  2427 zdvd_0_right           -> dvd_0_right
  2428 zdvd_0_left            -> dvd_0_left_iff
  2429 zdvd_1_left            -> one_dvd
  2430 zminus_dvd_iff         -> minus_dvd_iff
  2431 
  2432 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  2433 
  2434 * The real numbers offer decimal input syntax: 12.34 is translated
  2435 into 1234/10^2. This translation is not reversed upon output.
  2436 
  2437 * Theory Library/Polynomial defines an abstract type 'a poly of
  2438 univariate polynomials with coefficients of type 'a.  In addition to
  2439 the standard ring operations, it also supports div and mod.  Code
  2440 generation is also supported, using list-style constructors.
  2441 
  2442 * Theory Library/Inner_Product defines a class of real_inner for real
  2443 inner product spaces, with an overloaded operation inner :: 'a => 'a
  2444 => real.  Class real_inner is a subclass of real_normed_vector from
  2445 theory RealVector.
  2446 
  2447 * Theory Library/Product_Vector provides instances for the product
  2448 type 'a * 'b of several classes from RealVector and Inner_Product.
  2449 Definitions of addition, subtraction, scalar multiplication, norms,
  2450 and inner products are included.
  2451 
  2452 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  2453 addition to the field operations, numerals and case syntax are also
  2454 supported.
  2455 
  2456 * Theory Library/Diagonalize provides constructive version of Cantor's
  2457 first diagonalization argument.
  2458 
  2459 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  2460 zlcm (for int); carried together from various gcd/lcm developements in
  2461 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  2462 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  2463 may recover tupled syntax as follows:
  2464 
  2465     hide (open) const gcd
  2466     abbreviation gcd where
  2467       "gcd == (%(a, b). GCD.gcd a b)"
  2468     notation (output)
  2469       GCD.gcd ("gcd '(_, _')")
  2470 
  2471 The same works for lcm, zgcd, zlcm.
  2472 
  2473 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  2474 instantiations for algebraic structures.  Removed some duplicate
  2475 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  2476 
  2477 * ML antiquotation @{code} takes a constant as argument and generates
  2478 corresponding code in background and inserts name of the corresponding
  2479 resulting ML value/function/datatype constructor binding in place.
  2480 All occurrences of @{code} with a single ML block are generated
  2481 simultaneously.  Provides a generic and safe interface for
  2482 instrumentalizing code generation.  See
  2483 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  2484 In future you ought to refrain from ad-hoc compiling generated SML
  2485 code on the ML toplevel.  Note that (for technical reasons) @{code}
  2486 cannot refer to constants for which user-defined serializations are
  2487 set.  Refer to the corresponding ML counterpart directly in that
  2488 cases.
  2489 
  2490 * Command 'rep_datatype': instead of theorem names the command now
  2491 takes a list of terms denoting the constructors of the type to be
  2492 represented as datatype.  The characteristic theorems have to be
  2493 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  2494 have disappeared in favour of existing ones:
  2495 
  2496     unit_induct                 ~> unit.induct
  2497     prod_induct                 ~> prod.induct
  2498     sum_induct                  ~> sum.induct
  2499     Suc_Suc_eq                  ~> nat.inject
  2500     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  2501 
  2502 
  2503 *** HOL-Algebra ***
  2504 
  2505 * New locales for orders and lattices where the equivalence relation
  2506 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  2507 locales use a record structure with field eq for the equivalence.
  2508 
  2509 * New theory of factorial domains.
  2510 
  2511 * Units_l_inv and Units_r_inv are now simp rules by default.
  2512 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  2513 and/or r_inv will now also require deletion of these lemmas.
  2514 
  2515 * Renamed the following theorems, INCOMPATIBILITY:
  2516 
  2517 UpperD ~> Upper_memD
  2518 LowerD ~> Lower_memD
  2519 least_carrier ~> least_closed
  2520 greatest_carrier ~> greatest_closed
  2521 greatest_Lower_above ~> greatest_Lower_below
  2522 one_zero ~> carrier_one_zero
  2523 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  2524 
  2525 
  2526 *** HOL-Nominal ***
  2527 
  2528 * Nominal datatypes can now contain type-variables.
  2529 
  2530 * Commands 'nominal_inductive' and 'equivariance' work with local
  2531 theory targets.
  2532 
  2533 * Nominal primrec can now works with local theory targets and its
  2534 specification syntax now conforms to the general format as seen in
  2535 'inductive' etc.
  2536 
  2537 * Method "perm_simp" honours the standard simplifier attributes
  2538 (no_asm), (no_asm_use) etc.
  2539 
  2540 * The new predicate #* is defined like freshness, except that on the
  2541 left hand side can be a set or list of atoms.
  2542 
  2543 * Experimental command 'nominal_inductive2' derives strong induction
  2544 principles for inductive definitions.  In contrast to
  2545 'nominal_inductive', which can only deal with a fixed number of
  2546 binders, it can deal with arbitrary expressions standing for sets of
  2547 atoms to be avoided.  The only inductive definition we have at the
  2548 moment that needs this generalisation is the typing rule for Lets in
  2549 the algorithm W:
  2550 
  2551  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  2552  -----------------------------------------------------------------
  2553          Gamma |- Let x be t1 in t2 : T2
  2554 
  2555 In this rule one wants to avoid all the binders that are introduced by
  2556 "close Gamma T1".  We are looking for other examples where this
  2557 feature might be useful.  Please let us know.
  2558 
  2559 
  2560 *** HOLCF ***
  2561 
  2562 * Reimplemented the simplification procedure for proving continuity
  2563 subgoals.  The new simproc is extensible; users can declare additional
  2564 continuity introduction rules with the attribute [cont2cont].
  2565 
  2566 * The continuity simproc now uses a different introduction rule for
  2567 solving continuity subgoals on terms with lambda abstractions.  In
  2568 some rare cases the new simproc may fail to solve subgoals that the
  2569 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  2570 Potential INCOMPATIBILITY.
  2571 
  2572 * Command 'fixrec': specification syntax now conforms to the general
  2573 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  2574 examples.  INCOMPATIBILITY.
  2575 
  2576 
  2577 *** ZF ***
  2578 
  2579 * Proof of Zorn's Lemma for partial orders.
  2580 
  2581 
  2582 *** ML ***
  2583 
  2584 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  2585 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  2586 depends on multithreading, so timouts will not work before Poly/ML
  2587 5.2.1!
  2588 
  2589 * High-level support for concurrent ML programming, see
  2590 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  2591 particularly convenient to organize independent functional
  2592 computations.  The concept of "synchronized variables" provides a
  2593 higher-order interface for components with shared state, avoiding the
  2594 delicate details of mutexes and condition variables.  (Requires
  2595 Poly/ML 5.2.1 or later.)
  2596 
  2597 * ML bindings produced via Isar commands are stored within the Isar
  2598 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2599 become thread-safe and work with undo as expected (concerning
  2600 top-level bindings, not side-effects on global references).
  2601 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2602 compiler at runtime; really global bindings need to be given outside a
  2603 theory.  (Requires Poly/ML 5.2 or later.)
  2604 
  2605 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2606 context.  Top-level ML bindings are stored within the proof context in
  2607 a purely sequential fashion, disregarding the nested proof structure.
  2608 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2609 proof.  (Requires Poly/ML 5.2 or later.)
  2610 
  2611 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2612 and Method.setup, as well as Isar commands 'attribute_setup' and
  2613 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2614 existing code accordingly, or use plain 'setup' together with old
  2615 Method.add_method.
  2616 
  2617 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2618 to 'a -> thm, while results are always tagged with an authentic oracle
  2619 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2620 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2621 accordingly.  Note that extra performance may be gained by producing
  2622 the cterm carefully, avoiding slow Thm.cterm_of.
  2623 
  2624 * Simplified interface for defining document antiquotations via
  2625 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2626 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2627 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2628 examples.
  2629 
  2630 * More systematic treatment of long names, abstract name bindings, and
  2631 name space operations.  Basic operations on qualified names have been
  2632 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2633 Long_Name.append.  Old type bstring has been mostly replaced by
  2634 abstract type binding (see structure Binding), which supports precise
  2635 qualification by packages and local theory targets, as well as proper
  2636 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2637 bstring values into Binding.name, or better pass through abstract
  2638 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2639 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2640 
  2641 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2642 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2643 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2644 
  2645 * Disposed old type and term read functions (Sign.read_def_typ,
  2646 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2647 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2648 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2649 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2650 resort for legacy applications.
  2651 
  2652 * Disposed old declarations, tactics, tactic combinators that refer to
  2653 the simpset or claset of an implicit theory (such as Addsimps,
  2654 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2655 embedded ML text, or local_simpset_of with a proper context passed as
  2656 explicit runtime argument.
  2657 
  2658 * Rules and tactics that read instantiations (read_instantiate,
  2659 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2660 context, which is required for parsing and type-checking.  Moreover,
  2661 the variables are specified as plain indexnames, not string encodings
  2662 thereof.  INCOMPATIBILITY.
  2663 
  2664 * Generic Toplevel.add_hook interface allows to analyze the result of
  2665 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2666 for theorem dependency output of transactions resulting in a new
  2667 theory state.
  2668 
  2669 * ML antiquotations: block-structured compilation context indicated by
  2670 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2671 
  2672   @{binding name}                         - basic name binding
  2673   @{let ?pat = term}                      - term abbreviation (HO matching)
  2674   @{note name = fact}                     - fact abbreviation
  2675   @{thm fact}                             - singleton fact (with attributes)
  2676   @{thms fact}                            - general fact (with attributes)
  2677   @{lemma prop by method}                 - singleton goal
  2678   @{lemma prop by meth1 meth2}            - singleton goal
  2679   @{lemma prop1 ... propN by method}      - general goal
  2680   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2681   @{lemma (open) ...}                     - open derivation
  2682 
  2683 
  2684 *** System ***
  2685 
  2686 * The Isabelle "emacs" tool provides a specific interface to invoke
  2687 Proof General / Emacs, with more explicit failure if that is not
  2688 installed (the old isabelle-interface script silently falls back on
  2689 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2690 installation location of the Proof General distribution.
  2691 
  2692 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2693 the Isabelle process into a JVM/Scala application.  See
  2694 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2695 process wrapper has been discontinued.)
  2696 
  2697 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2698 
  2699 * Various status messages (with exact source position information) are
  2700 emitted, if proper markup print mode is enabled.  This allows
  2701 user-interface components to provide detailed feedback on internal
  2702 prover operations.
  2703 
  2704 
  2705 
  2706 New in Isabelle2008 (June 2008)
  2707 -------------------------------
  2708 
  2709 *** General ***
  2710 
  2711 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2712 and updated, with formally checked references as hyperlinks.
  2713 
  2714 * Theory loader: use_thy (and similar operations) no longer set the
  2715 implicit ML context, which was occasionally hard to predict and in
  2716 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2717 provides a proper context already.
  2718 
  2719 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2720 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2721 'use' within a theory file will do the job.
  2722 
  2723 * Name space merge now observes canonical order, i.e. the second space
  2724 is inserted into the first one, while existing entries in the first
  2725 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2726 swap theory imports.
  2727 
  2728 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2729 INCOMPATIBILITY in identifier syntax etc.
  2730 
  2731 * Outer syntax: string tokens no longer admit escaped white space,
  2732 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2733 white space without escapes.
  2734 
  2735 * Outer syntax: string tokens may contain arbitrary character codes
  2736 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2737 "foo_bar".
  2738 
  2739 
  2740 *** Pure ***
  2741 
  2742 * Context-dependent token translations.  Default setup reverts locally
  2743 fixed variables, and adds hilite markup for undeclared frees.
  2744 
  2745 * Unused theorems can be found using the new command 'unused_thms'.
  2746 There are three ways of invoking it:
  2747 
  2748 (1) unused_thms
  2749      Only finds unused theorems in the current theory.
  2750 
  2751 (2) unused_thms thy_1 ... thy_n -
  2752      Finds unused theorems in the current theory and all of its ancestors,
  2753      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2754 
  2755 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2756      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2757      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2758      their ancestors.
  2759 
  2760 In order to increase the readability of the list produced by
  2761 unused_thms, theorems that have been created by a particular instance
  2762 of a theory command such as 'inductive' or 'function' are considered
  2763 to belong to the same "group", meaning that if at least one theorem in
  2764 this group is used, the other theorems in the same group are no longer
  2765 reported as unused.  Moreover, if all theorems in the group are
  2766 unused, only one theorem in the group is displayed.
  2767 
  2768 Note that proof objects have to be switched on in order for
  2769 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2770 usually the case when using Proof General with the default settings).
  2771 
  2772 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2773 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2774 duplicate fact bindings, or even accidental fact duplications.  Note
  2775 that tools may maintain dynamically scoped facts systematically, using
  2776 PureThy.add_thms_dynamic.
  2777 
  2778 * Command 'hide' now allows to hide from "fact" name space as well.
  2779 
  2780 * Eliminated destructive theorem database, simpset, claset, and
  2781 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2782 update of theories within ML code.
  2783 
  2784 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2785 INCOMPATIBILITY, object-logics depending on former Pure require
  2786 additional setup PureThy.old_appl_syntax_setup; object-logics
  2787 depending on former CPure need to refer to Pure.
  2788 
  2789 * Commands 'use' and 'ML' are now purely functional, operating on
  2790 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2791 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2792 INCOMPATIBILITY.
  2793 
  2794 * Command 'setup': discontinued implicit version with ML reference.
  2795 
  2796 * Instantiation target allows for simultaneous specification of class
  2797 instance operations together with an instantiation proof.
  2798 Type-checking phase allows to refer to class operations uniformly.
  2799 See src/HOL/Complex/Complex.thy for an Isar example and
  2800 src/HOL/Library/Eval.thy for an ML example.
  2801 
  2802 * Indexing of literal facts: be more serious about including only
  2803 facts from the visible specification/proof context, but not the
  2804 background context (locale etc.).  Affects `prop` notation and method
  2805 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2806 situations.
  2807 
  2808 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2809 "(open)" option, which used to expose internal bound variables to the
  2810 proof text.
  2811 
  2812 * Isar statements: removed obsolete case "rule_context".
  2813 INCOMPATIBILITY, better use explicit fixes/assumes.
  2814 
  2815 * Locale proofs: default proof step now includes 'unfold_locales';
  2816 hence 'proof' without argument may be used to unfold locale
  2817 predicates.
  2818 
  2819 
  2820 *** Document preparation ***
  2821 
  2822 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2823 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2824 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2825 spot); renamed link color from "darkblue" to "linkcolor" (default
  2826 value unchanged, can be redefined via \definecolor); no longer sets
  2827 "a4paper" option (unnecessary or even intrusive).
  2828 
  2829 * Antiquotation @{lemma A method} proves proposition A by the given
  2830 method (either a method name or a method name plus (optional) method
  2831 arguments in parentheses) and prints A just like @{prop A}.
  2832 
  2833 
  2834 *** HOL ***
  2835 
  2836 * New primrec package.  Specification syntax conforms in style to
  2837 definition/function/....  No separate induction rule is provided.  The
  2838 "primrec" command distinguishes old-style and new-style specifications
  2839 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2840 When adjusting theories, beware: constants stemming from new-style
  2841 primrec specifications have authentic syntax.
  2842 
  2843 * Metis prover is now an order of magnitude faster, and also works
  2844 with multithreading.
  2845 
  2846 * Metis: the maximum number of clauses that can be produced from a
  2847 theorem is now given by the attribute max_clauses.  Theorems that
  2848 exceed this number are ignored, with a warning printed.
  2849 
  2850 * Sledgehammer no longer produces structured proofs by default. To
  2851 enable, declare [[sledgehammer_full = true]].  Attributes
  2852 reconstruction_modulus, reconstruction_sorts renamed
  2853 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2854 
  2855 * Method "induct_scheme" derives user-specified induction rules
  2856 from well-founded induction and completeness of patterns. This factors
  2857 out some operations that are done internally by the function package
  2858 and makes them available separately.  See
  2859 src/HOL/ex/Induction_Scheme.thy for examples.
  2860 
  2861 * More flexible generation of measure functions for termination
  2862 proofs: Measure functions can be declared by proving a rule of the
  2863 form "is_measure f" and giving it the [measure_function] attribute.
  2864 The "is_measure" predicate is logically meaningless (always true), and
  2865 just guides the heuristic.  To find suitable measure functions, the
  2866 termination prover sets up the goal "is_measure ?f" of the appropriate
  2867 type and generates all solutions by prolog-style backwards proof using
  2868 the declared rules.
  2869 
  2870 This setup also deals with rules like 
  2871 
  2872   "is_measure f ==> is_measure (list_size f)"
  2873 
  2874 which accommodates nested datatypes that recurse through lists.
  2875 Similar rules are predeclared for products and option types.
  2876 
  2877 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  2878 
  2879   INCOMPATIBILITIES:
  2880 
  2881   - Definitions of overloaded constants on sets have to be replaced by
  2882     definitions on => and bool.
  2883 
  2884   - Some definitions of overloaded operators on sets can now be proved
  2885     using the definitions of the operators on => and bool.  Therefore,
  2886     the following theorems have been renamed:
  2887 
  2888       subset_def   -> subset_eq
  2889       psubset_def  -> psubset_eq
  2890       set_diff_def -> set_diff_eq
  2891       Compl_def    -> Compl_eq
  2892       Sup_set_def  -> Sup_set_eq
  2893       Inf_set_def  -> Inf_set_eq
  2894       sup_set_def  -> sup_set_eq
  2895       inf_set_def  -> inf_set_eq
  2896 
  2897   - Due to the incompleteness of the HO unification algorithm, some
  2898     rules such as subst may require manual instantiation, if some of
  2899     the unknowns in the rule is a set.
  2900 
  2901   - Higher order unification and forward proofs:
  2902     The proof pattern
  2903 
  2904       have "P (S::'a set)" <...>
  2905       then have "EX S. P S" ..
  2906 
  2907     no longer works (due to the incompleteness of the HO unification
  2908     algorithm) and must be replaced by the pattern
  2909 
  2910       have "EX S. P S"
  2911       proof
  2912         show "P S" <...>
  2913       qed
  2914 
  2915   - Calculational reasoning with subst (or similar rules):
  2916     The proof pattern
  2917 
  2918       have "P (S::'a set)" <...>
  2919       also have "S = T" <...>
  2920       finally have "P T" .
  2921 
  2922     no longer works (for similar reasons as the previous example) and
  2923     must be replaced by something like
  2924 
  2925       have "P (S::'a set)" <...>
  2926       moreover have "S = T" <...>
  2927       ultimately have "P T" by simp
  2928 
  2929   - Tactics or packages written in ML code:
  2930     Code performing pattern matching on types via
  2931 
  2932       Type ("set", [T]) => ...
  2933 
  2934     must be rewritten. Moreover, functions like strip_type or
  2935     binder_types no longer return the right value when applied to a
  2936     type of the form
  2937 
  2938       T1 => ... => Tn => U => bool
  2939 
  2940     rather than
  2941 
  2942       T1 => ... => Tn => U set
  2943 
  2944 * Merged theories Wellfounded_Recursion, Accessible_Part and
  2945 Wellfounded_Relations to theory Wellfounded.
  2946 
  2947 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  2948 
  2949 * Class finite no longer treats UNIV as class parameter.  Use class
  2950 enum from theory Library/Enum instead to achieve a similar effect.
  2951 INCOMPATIBILITY.
  2952 
  2953 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  2954 and "Cons".  INCOMPATIBILITY.
  2955 
  2956 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  2957 Potential INCOMPATIBILITY.
  2958 
  2959 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  2960 injective_fst_snd removed, use split_eta and prod_eqI instead.
  2961 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  2962 
  2963 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  2964 the same name in theory Orderings:
  2965 
  2966   less_trans
  2967   less_linear
  2968   le_imp_less_or_eq
  2969   le_less_trans
  2970   less_le_trans
  2971   less_not_sym
  2972   less_asym
  2973 
  2974 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  2975 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  2976 and different variable names.
  2977 
  2978 * Library/Option_ord.thy: Canonical order on option type.
  2979 
  2980 * Library/RBT.thy: Red-black trees, an efficient implementation of
  2981 finite maps.
  2982 
  2983 * Library/Countable.thy: Type class for countable types.
  2984 
  2985 * Theory Int: The representation of numerals has changed.  The infix
  2986 operator BIT and the bit datatype with constructors B0 and B1 have
  2987 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  2988 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  2989 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  2990 accordingly.
  2991 
  2992 * Theory Nat: definition of <= and < on natural numbers no longer
  2993 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  2994 le_def and less_def have disappeared.  Consider lemmas not_less
  2995 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  2996 
  2997 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  2998 (whose purpose mainly is for various fold_set functionals) have been
  2999 abandoned in favor of the existing algebraic classes
  3000 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  3001 lower_semilattice (resp. upper_semilattice) and linorder.
  3002 INCOMPATIBILITY.
  3003 
  3004 * Theory Transitive_Closure: induct and cases rules now declare proper
  3005 case_names ("base" and "step").  INCOMPATIBILITY.
  3006 
  3007 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  3008 lattices.  The form set-specific version is available as
  3009 Inductive.lfp_ordinal_induct_set.
  3010 
  3011 * Renamed theorems "power.simps" to "power_int.simps".
  3012 INCOMPATIBILITY.
  3013 
  3014 * Class semiring_div provides basic abstract properties of semirings
  3015 with division and modulo operations.  Subsumes former class dvd_mod.
  3016 
  3017 * Merged theories IntDef, Numeral and IntArith into unified theory
  3018 Int.  INCOMPATIBILITY.
  3019 
  3020 * Theory Library/Code_Index: type "index" now represents natural
  3021 numbers rather than integers.  INCOMPATIBILITY.
  3022 
  3023 * New class "uminus" with operation "uminus" (split of from class
  3024 "minus" which now only has operation "minus", binary).
  3025 INCOMPATIBILITY.
  3026 
  3027 * Constants "card", "internal_split", "option_map" now with authentic
  3028 syntax.  INCOMPATIBILITY.
  3029 
  3030 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  3031 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  3032 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  3033 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  3034 Sup_set_def, le_def, less_def, option_map_def now with object
  3035 equality.  INCOMPATIBILITY.
  3036 
  3037 * Records. Removed K_record, and replaced it by pure lambda term
  3038 %x. c. The simplifier setup is now more robust against eta expansion.
  3039 INCOMPATIBILITY: in cases explicitly referring to K_record.
  3040 
  3041 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  3042 
  3043 * Library/ListVector: new theory of arithmetic vector operations.
  3044 
  3045 * Library/Order_Relation: new theory of various orderings as sets of
  3046 pairs.  Defines preorders, partial orders, linear orders and
  3047 well-orders on sets and on types.
  3048 
  3049 
  3050 *** ZF ***
  3051 
  3052 * Renamed some theories to allow to loading both ZF and HOL in the
  3053 same session:
  3054 
  3055   Datatype  -> Datatype_ZF
  3056   Inductive -> Inductive_ZF
  3057   Int       -> Int_ZF
  3058   IntDiv    -> IntDiv_ZF
  3059   Nat       -> Nat_ZF
  3060   List      -> List_ZF
  3061   Main      -> Main_ZF
  3062 
  3063 INCOMPATIBILITY: ZF theories that import individual theories below
  3064 Main might need to be adapted.  Regular theory Main is still
  3065 available, as trivial extension of Main_ZF.
  3066 
  3067 
  3068 *** ML ***
  3069 
  3070 * ML within Isar: antiquotation @{const name} or @{const
  3071 name(typargs)} produces statically-checked Const term.
  3072 
  3073 * Functor NamedThmsFun: data is available to the user as dynamic fact
  3074 (of the same name).  Removed obsolete print command.
  3075 
  3076 * Removed obsolete "use_legacy_bindings" function.
  3077 
  3078 * The ``print mode'' is now a thread-local value derived from a global
  3079 template (the former print_mode reference), thus access becomes
  3080 non-critical.  The global print_mode reference is for session
  3081 management only; user-code should use print_mode_value,
  3082 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  3083 
  3084 * Functions system/system_out provide a robust way to invoke external
  3085 shell commands, with propagation of interrupts (requires Poly/ML
  3086 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  3087 
  3088 
  3089 *** System ***
  3090 
  3091 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  3092 in accordance with Proof General 3.7, which prefers GNU emacs.
  3093 
  3094 * isatool tty runs Isabelle process with plain tty interaction;
  3095 optional line editor may be specified via ISABELLE_LINE_EDITOR
  3096 setting, the default settings attempt to locate "ledit" and "rlwrap".
  3097 
  3098 * isatool browser now works with Cygwin as well, using general
  3099 "javapath" function defined in Isabelle process environment.
  3100 
  3101 * YXML notation provides a simple and efficient alternative to
  3102 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  3103 isatool yxml as described in the Isabelle system manual.
  3104 
  3105 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  3106 provides general wrapper for managing an Isabelle process in a robust
  3107 fashion, with ``cooked'' output from stdin/stderr.
  3108 
  3109 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  3110 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  3111 
  3112 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  3113 way of changing the user's settings is via
  3114 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  3115 script.
  3116 
  3117 * Multithreading.max_threads := 0 refers to the number of actual CPU
  3118 cores of the underlying machine, which is a good starting point for
  3119 optimal performance tuning.  The corresponding usedir option -M allows
  3120 "max" as an alias for "0".  WARNING: does not work on certain versions
  3121 of Mac OS (with Poly/ML 5.1).
  3122 
  3123 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  3124 adverse effect of Isabelle flooding interactive front-ends (notably
  3125 ProofGeneral / XEmacs).
  3126 
  3127 
  3128 
  3129 New in Isabelle2007 (November 2007)
  3130 -----------------------------------
  3131 
  3132 *** General ***
  3133 
  3134 * More uniform information about legacy features, notably a
  3135 warning/error of "Legacy feature: ...", depending on the state of the
  3136 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  3137 legacy features will disappear eventually.
  3138 
  3139 * Theory syntax: the header format ``theory A = B + C:'' has been
  3140 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  3141 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  3142 
  3143 * Theory syntax: the old non-Isar theory file format has been
  3144 discontinued altogether.  Note that ML proof scripts may still be used
  3145 with Isar theories; migration is usually quite simple with the ML
  3146 function use_legacy_bindings.  INCOMPATIBILITY.
  3147 
  3148 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  3149 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  3150 quotes.
  3151 
  3152 * Theory loader: be more serious about observing the static theory
  3153 header specifications (including optional directories), but not the
  3154 accidental file locations of previously successful loads.  The strict
  3155 update policy of former update_thy is now already performed by
  3156 use_thy, so the former has been removed; use_thys updates several
  3157 theories simultaneously, just as 'imports' within a theory header
  3158 specification, but without merging the results.  Potential
  3159 INCOMPATIBILITY: may need to refine theory headers and commands
  3160 ROOT.ML which depend on load order.
  3161 
  3162 * Theory loader: optional support for content-based file
  3163 identification, instead of the traditional scheme of full physical
  3164 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  3165 (cf. the system manual).  The new scheme allows to work with
  3166 non-finished theories in persistent session images, such that source
  3167 files may be moved later on without requiring reloads.
  3168 
  3169 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3170 file (with the same base name as the theory) are considered a legacy
  3171 feature, which will disappear eventually. Even now, the theory loader
  3172 no longer maintains dependencies on such files.
  3173 
  3174 * Syntax: the scope for resolving ambiguities via type-inference is
  3175 now limited to individual terms, instead of whole simultaneous
  3176 specifications as before. This greatly reduces the complexity of the
  3177 syntax module and improves flexibility by separating parsing and
  3178 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  3179 'fixes' etc.) are required in rare situations.
  3180 
  3181 * Syntax: constants introduced by new-style packages ('definition',
  3182 'abbreviation' etc.) are passed through the syntax module in
  3183 ``authentic mode''. This means that associated mixfix annotations
  3184 really stick to such constants, independently of potential name space
  3185 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  3186 trees are represented slightly differently, may need to adapt syntax
  3187 translations accordingly. Use CONST marker in 'translations' and
  3188 @{const_syntax} antiquotation in 'parse_translation' etc.
  3189 
  3190 * Legacy goal package: reduced interface to the bare minimum required
  3191 to keep existing proof scripts running.  Most other user-level
  3192 functions are now part of the OldGoals structure, which is *not* open
  3193 by default (consider isatool expandshort before open OldGoals).
  3194 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  3195 these tend to cause confusion about the actual goal (!) context being
  3196 used here, which is not necessarily the same as the_context().
  3197 
  3198 * Command 'find_theorems': supports "*" wild-card in "name:"
  3199 criterion; "with_dups" option.  Certain ProofGeneral versions might
  3200 support a specific search form (see ProofGeneral/CHANGES).
  3201 
  3202 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  3203 by default, which means that "prems" (and also "fixed variables") are
  3204 suppressed from proof state output.  Note that the ProofGeneral
  3205 settings mechanism allows to change and save options persistently, but
  3206 older versions of Isabelle will fail to start up if a negative prems
  3207 limit is imposed.
  3208 
  3209 * Local theory targets may be specified by non-nested blocks of
  3210 ``context/locale/class ... begin'' followed by ``end''.  The body may
  3211 contain definitions, theorems etc., including any derived mechanism
  3212 that has been implemented on top of these primitives.  This concept
  3213 generalizes the existing ``theorem (in ...)'' towards more versatility
  3214 and scalability.
  3215 
  3216 * Proof General interface: proper undo of final 'end' command;
  3217 discontinued Isabelle/classic mode (ML proof scripts).
  3218 
  3219 
  3220 *** Document preparation ***
  3221 
  3222 * Added antiquotation @{theory name} which prints the given name,
  3223 after checking that it refers to a valid ancestor theory in the
  3224 current context.
  3225 
  3226 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  3227 check the given source text as ML type/structure, printing verbatim.
  3228 
  3229 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  3230 "c args == rhs" given in the current context.  (Any number of
  3231 arguments may be given on the LHS.)
  3232 
  3233 
  3234 *** Pure ***
  3235 
  3236 * The 'class' package offers a combination of axclass and locale to
  3237 achieve Haskell-like type classes in Isabelle.  Definitions and
  3238 theorems within a class context produce both relative results (with
  3239 implicit parameters according to the locale context), and polymorphic
  3240 constants with qualified polymorphism (according to the class
  3241 context).  Within the body context of a 'class' target, a separate
  3242 syntax layer ("user space type system") takes care of converting
  3243 between global polymorphic consts and internal locale representation.
  3244 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  3245 "isatool doc classes" provides a tutorial.
  3246 
  3247 * Generic code generator framework allows to generate executable
  3248 code for ML and Haskell (including Isabelle classes).  A short usage
  3249 sketch:
  3250 
  3251     internal compilation:
  3252         export_code <list of constants (term syntax)> in SML
  3253     writing SML code to a file:
  3254         export_code <list of constants (term syntax)> in SML <filename>
  3255     writing OCaml code to a file:
  3256         export_code <list of constants (term syntax)> in OCaml <filename>
  3257     writing Haskell code to a bunch of files:
  3258         export_code <list of constants (term syntax)> in Haskell <filename>
  3259 
  3260     evaluating closed propositions to True/False using code generation:
  3261         method ``eval''
  3262 
  3263 Reasonable default setup of framework in HOL.
  3264 
  3265 Theorem attributs for selecting and transforming function equations theorems:
  3266 
  3267     [code fun]:        select a theorem as function equation for a specific constant
  3268     [code fun del]:    deselect a theorem as function equation for a specific constant
  3269     [code inline]:     select an equation theorem for unfolding (inlining) in place
  3270     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  3271 
  3272 User-defined serializations (target in {SML, OCaml, Haskell}):
  3273 
  3274     code_const <and-list of constants (term syntax)>
  3275       {(target) <and-list of const target syntax>}+
  3276 
  3277     code_type <and-list of type constructors>
  3278       {(target) <and-list of type target syntax>}+
  3279 
  3280     code_instance <and-list of instances>
  3281       {(target)}+
  3282         where instance ::= <type constructor> :: <class>
  3283 
  3284     code_class <and_list of classes>
  3285       {(target) <and-list of class target syntax>}+
  3286         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  3287 
  3288 code_instance and code_class only are effective to target Haskell.
  3289 
  3290 For example usage see src/HOL/ex/Codegenerator.thy and
  3291 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  3292 generation from Isabelle/HOL theories is available via "isatool doc
  3293 codegen".
  3294 
  3295 * Code generator: consts in 'consts_code' Isar commands are now
  3296 referred to by usual term syntax (including optional type
  3297 annotations).
  3298 
  3299 * Command 'no_translations' removes translation rules from theory
  3300 syntax.
  3301 
  3302 * Overloaded definitions are now actually checked for acyclic
  3303 dependencies.  The overloading scheme is slightly more general than
  3304 that of Haskell98, although Isabelle does not demand an exact
  3305 correspondence to type class and instance declarations.
  3306 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  3307 exotic versions of overloading -- at the discretion of the user!
  3308 
  3309 Polymorphic constants are represented via type arguments, i.e. the
  3310 instantiation that matches an instance against the most general
  3311 declaration given in the signature.  For example, with the declaration
  3312 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  3313 as c(nat).  Overloading is essentially simultaneous structural
  3314 recursion over such type arguments.  Incomplete specification patterns
  3315 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  3316 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  3317 Command 'print_theory' outputs the normalized system of recursive
  3318 equations, see section "definitions".
  3319 
  3320 * Configuration options are maintained within the theory or proof
  3321 context (with name and type bool/int/string), providing a very simple
  3322 interface to a poor-man's version of general context data.  Tools may
  3323 declare options in ML (e.g. using Attrib.config_int) and then refer to
  3324 these values using Config.get etc.  Users may change options via an
  3325 associated attribute of the same name.  This form of context
  3326 declaration works particularly well with commands 'declare' or
  3327 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  3328 very easy to avoid global references, which would not observe Isar
  3329 toplevel undo/redo and fail to work with multithreading.
  3330 
  3331 Various global ML references of Pure and HOL have been turned into
  3332 configuration options:
  3333 
  3334   Unify.search_bound		unify_search_bound
  3335   Unify.trace_bound		unify_trace_bound
  3336   Unify.trace_simp		unify_trace_simp
  3337   Unify.trace_types		unify_trace_types
  3338   Simplifier.simp_depth_limit	simp_depth_limit
  3339   Blast.depth_limit		blast_depth_limit
  3340   DatatypeProp.dtK		datatype_distinctness_limit
  3341   fast_arith_neq_limit  	fast_arith_neq_limit
  3342   fast_arith_split_limit	fast_arith_split_limit
  3343 
  3344 * Named collections of theorems may be easily installed as context
  3345 data using the functor NamedThmsFun (see also
  3346 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  3347 attributes; there is also a toplevel print command.  This facility is
  3348 just a common case of general context data, which is the preferred way
  3349 for anything more complex than just a list of facts in canonical
  3350 order.
  3351 
  3352 * Isar: command 'declaration' augments a local theory by generic
  3353 declaration functions written in ML.  This enables arbitrary content
  3354 being added to the context, depending on a morphism that tells the
  3355 difference of the original declaration context wrt. the application
  3356 context encountered later on.
  3357 
  3358 * Isar: proper interfaces for simplification procedures.  Command
  3359 'simproc_setup' declares named simprocs (with match patterns, and body
  3360 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  3361 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  3362 
  3363 * Isar: an extra pair of brackets around attribute declarations
  3364 abbreviates a theorem reference involving an internal dummy fact,
  3365 which will be ignored later --- only the effect of the attribute on
  3366 the background context will persist.  This form of in-place
  3367 declarations is particularly useful with commands like 'declare' and
  3368 'using', for example ``have A using [[simproc a]] by simp''.
  3369 
  3370 * Isar: method "assumption" (and implicit closing of subproofs) now
  3371 takes simple non-atomic goal assumptions into account: after applying
  3372 an assumption as a rule the resulting subgoals are solved by atomic
  3373 assumption steps.  This is particularly useful to finish 'obtain'
  3374 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  3375 without referring to the original premise "!!x. P x ==> thesis" in the
  3376 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  3377 more permissive.
  3378 
  3379 * Isar: implicit use of prems from the Isar proof context is
  3380 considered a legacy feature.  Common applications like ``have A .''
  3381 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  3382 referencing facts explicitly here improves readability and
  3383 maintainability of proof texts.
  3384 
  3385 * Isar: improper proof element 'guess' is like 'obtain', but derives
  3386 the obtained context from the course of reasoning!  For example:
  3387 
  3388   assume "EX x y. A x & B y"   -- "any previous fact"
  3389   then guess x and y by clarify
  3390 
  3391 This technique is potentially adventurous, depending on the facts and
  3392 proof tools being involved here.
  3393 
  3394 * Isar: known facts from the proof context may be specified as literal
  3395 propositions, using ASCII back-quote syntax.  This works wherever
  3396 named facts used to be allowed so far, in proof commands, proof
  3397 methods, attributes etc.  Literal facts are retrieved from the context
  3398 according to unification of type and term parameters.  For example,
  3399 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  3400 theorems in the current context, then these are valid literal facts:
  3401 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  3402 
  3403 There is also a proof method "fact" which does the same composition
  3404 for explicit goal states, e.g. the following proof texts coincide with
  3405 certain special cases of literal facts:
  3406 
  3407   have "A" by fact                 ==  note `A`
  3408   have "A ==> B" by fact           ==  note `A ==> B`
  3409   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  3410   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  3411 
  3412 * Isar: ":" (colon) is no longer a symbolic identifier character in
  3413 outer syntax.  Thus symbolic identifiers may be used without
  3414 additional white space in declarations like this: ``assume *: A''.
  3415 
  3416 * Isar: 'print_facts' prints all local facts of the current context,
  3417 both named and unnamed ones.
  3418 
  3419 * Isar: 'def' now admits simultaneous definitions, e.g.:
  3420 
  3421   def x == "t" and y == "u"
  3422 
  3423 * Isar: added command 'unfolding', which is structurally similar to
  3424 'using', but affects both the goal state and facts by unfolding given
  3425 rewrite rules.  Thus many occurrences of the 'unfold' method or
  3426 'unfolded' attribute may be replaced by first-class proof text.
  3427 
  3428 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  3429 and command 'unfolding' now all support object-level equalities
  3430 (potentially conditional).  The underlying notion of rewrite rule is
  3431 analogous to the 'rule_format' attribute, but *not* that of the
  3432 Simplifier (which is usually more generous).
  3433 
  3434 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  3435 premises of a theorem by n. Useful in conjunction with drule.
  3436 
  3437 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  3438 method expression within a sandbox consisting of the first N
  3439 sub-goals, which need to exist.  For example, ``simp_all [3]''
  3440 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  3441 simplifies all new goals that emerge from applying rule foo to the
  3442 originally first one.
  3443 
  3444 * Isar: schematic goals are no longer restricted to higher-order
  3445 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  3446 expected.
  3447 
  3448 * Isar: the conclusion of a long theorem statement is now either
  3449 'shows' (a simultaneous conjunction, as before), or 'obtains'
  3450 (essentially a disjunction of cases with local parameters and
  3451 assumptions).  The latter allows to express general elimination rules
  3452 adequately; in this notation common elimination rules look like this:
  3453 
  3454   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  3455     assumes "EX x. P x"
  3456     obtains x where "P x"
  3457 
  3458   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  3459     assumes "A & B"
  3460     obtains A and B
  3461 
  3462   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  3463     assumes "A | B"
  3464     obtains
  3465       A
  3466     | B
  3467 
  3468 The subsequent classical rules even refer to the formal "thesis"
  3469 explicitly:
  3470 
  3471   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  3472     obtains "~ thesis"
  3473 
  3474   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  3475     obtains "thesis ==> something"
  3476 
  3477 The actual proof of an 'obtains' statement is analogous to that of the
  3478 Isar proof element 'obtain', only that there may be several cases.
  3479 Optional case names may be specified in parentheses; these will be
  3480 available both in the present proof and as annotations in the
  3481 resulting rule, for later use with the 'cases' method (cf. attribute
  3482 case_names).
  3483 
  3484 * Isar: the assumptions of a long theorem statement are available as
  3485 "assms" fact in the proof context.  This is more appropriate than the
  3486 (historical) "prems", which refers to all assumptions of the current
  3487 context, including those from the target locale, proof body etc.
  3488 
  3489 * Isar: 'print_statement' prints theorems from the current theory or
  3490 proof context in long statement form, according to the syntax of a
  3491 top-level lemma.
  3492 
  3493 * Isar: 'obtain' takes an optional case name for the local context
  3494 introduction rule (default "that").
  3495 
  3496 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  3497 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  3498 to occur.
  3499 
  3500 * Pure: syntax "CONST name" produces a fully internalized constant
  3501 according to the current context.  This is particularly useful for
  3502 syntax translations that should refer to internal constant
  3503 representations independently of name spaces.
  3504 
  3505 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  3506 instead of "FOO ". This allows multiple binder declarations to coexist
  3507 in the same context.  INCOMPATIBILITY.
  3508 
  3509 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  3510 primitive that also works in a locale context (both for constants and
  3511 fixed variables). Type declaration and internal syntactic representation
  3512 of given constants retrieved from the context. Likewise, the
  3513 'no_notation' command allows to remove given syntax annotations from the
  3514 current context.
  3515 
  3516 * Isar/locales: new derived specification elements 'axiomatization',
  3517 'definition', 'abbreviation', which support type-inference, admit
  3518 object-level specifications (equality, equivalence).  See also the
  3519 isar-ref manual.  Examples:
  3520 
  3521   axiomatization
  3522     eq  (infix "===" 50) where
  3523     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  3524 
  3525   definition "f x y = x + y + 1"
  3526   definition g where "g x = f x x"
  3527 
  3528   abbreviation
  3529     neq  (infix "=!=" 50) where
  3530     "x =!= y == ~ (x === y)"
  3531 
  3532 These specifications may be also used in a locale context.  Then the
  3533 constants being introduced depend on certain fixed parameters, and the
  3534 constant name is qualified by the locale base name.  An internal
  3535 abbreviation takes care for convenient input and output, making the
  3536 parameters implicit and using the original short name.  See also
  3537 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  3538 entities from a monomorphic theory.
  3539 
  3540 Presently, abbreviations are only available 'in' a target locale, but
  3541 not inherited by general import expressions.  Also note that
  3542 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  3543 'translations' in common applications.  The "no_abbrevs" print mode
  3544 prevents folding of abbreviations in term output.
  3545 
  3546 Concrete syntax is attached to specified constants in internal form,
  3547 independently of name spaces.  The parse tree representation is
  3548 slightly different -- use 'notation' instead of raw 'syntax', and
  3549 'translations' with explicit "CONST" markup to accommodate this.
  3550 
  3551 * Pure/Isar: unified syntax for new-style specification mechanisms
  3552 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  3553 full type inference and dummy patterns ("_").  For example:
  3554 
  3555   definition "K x _ = x"
  3556 
  3557   inductive conj for A B
  3558   where "A ==> B ==> conj A B"
  3559 
  3560 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  3561 the current context.  Print mode "no_abbrevs" prevents inversion of
  3562 abbreviations on output.
  3563 
  3564 * Isar/locales: improved parameter handling: use of locales "var" and
  3565 "struct" no longer necessary; - parameter renamings are no longer
  3566 required to be injective.  For example, this allows to define
  3567 endomorphisms as locale endom = homom mult mult h.
  3568 
  3569 * Isar/locales: changed the way locales with predicates are defined.
  3570 Instead of accumulating the specification, the imported expression is
  3571 now an interpretation.  INCOMPATIBILITY: different normal form of
  3572 locale expressions.  In particular, in interpretations of locales with
  3573 predicates, goals repesenting already interpreted fragments are not
  3574 removed automatically.  Use methods `intro_locales' and
  3575 `unfold_locales'; see below.
  3576 
  3577 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  3578 provide backward reasoning on locales predicates.  The methods are
  3579 aware of interpretations and discharge corresponding goals.
  3580 `intro_locales' is less aggressive then `unfold_locales' and does not
  3581 unfold predicates to assumptions.
  3582 
  3583 * Isar/locales: the order in which locale fragments are accumulated
  3584 has changed.  This enables to override declarations from fragments due
  3585 to interpretations -- for example, unwanted simp rules.
  3586 
  3587 * Isar/locales: interpretation in theories and proof contexts has been
  3588 extended.  One may now specify (and prove) equations, which are
  3589 unfolded in interpreted theorems.  This is useful for replacing
  3590 defined concepts (constants depending on locale parameters) by
  3591 concepts already existing in the target context.  Example:
  3592 
  3593   interpretation partial_order ["op <= :: [int, int] => bool"]
  3594     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3595 
  3596 Typically, the constant `partial_order.less' is created by a
  3597 definition specification element in the context of locale
  3598 partial_order.
  3599 
  3600 * Method "induct": improved internal context management to support
  3601 local fixes and defines on-the-fly. Thus explicit meta-level
  3602 connectives !!  and ==> are rarely required anymore in inductive goals
  3603 (using object-logic connectives for this purpose has been long
  3604 obsolete anyway). Common proof patterns are explained in
  3605 src/HOL/Induct/Common_Patterns.thy, see also
  3606 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3607 examples.
  3608 
  3609 * Method "induct": improved handling of simultaneous goals. Instead of
  3610 introducing object-level conjunction, the statement is now split into
  3611 several conclusions, while the corresponding symbolic cases are nested
  3612 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3613 see src/HOL/Induct/Common_Patterns.thy, for example.
  3614 
  3615 * Method "induct": mutual induction rules are now specified as a list
  3616 of rule sharing the same induction cases. HOL packages usually provide
  3617 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3618 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3619 mutual induction rules differently, i.e. like this:
  3620 
  3621   (induct rule: foo_bar.inducts)
  3622   (induct set: foo bar)
  3623   (induct pred: foo bar)
  3624   (induct type: foo bar)
  3625 
  3626 The ML function ProjectRule.projections turns old-style rules into the
  3627 new format.
  3628 
  3629 * Method "coinduct": dual of induction, see
  3630 src/HOL/Library/Coinductive_List.thy for various examples.
  3631 
  3632 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3633 considered a legacy feature.
  3634 
  3635 * Attribute "symmetric" produces result with standardized schematic
  3636 variables (index 0).  Potential INCOMPATIBILITY.
  3637 
  3638 * Simplifier: by default the simplifier trace only shows top level
  3639 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3640 default. Thus there is less danger of being flooded by the trace. The
  3641 trace indicates where parts have been suppressed.
  3642   
  3643 * Provers/classical: removed obsolete classical version of elim_format
  3644 attribute; classical elim/dest rules are now treated uniformly when
  3645 manipulating the claset.
  3646 
  3647 * Provers/classical: stricter checks to ensure that supplied intro,
  3648 dest and elim rules are well-formed; dest and elim rules must have at
  3649 least one premise.
  3650 
  3651 * Provers/classical: attributes dest/elim/intro take an optional
  3652 weight argument for the rule (just as the Pure versions).  Weights are
  3653 ignored by automated tools, but determine the search order of single
  3654 rule steps.
  3655 
  3656 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3657 where the body does not mention the bound variable.  Note that dummy
  3658 patterns implicitly depend on their context of bounds, which makes
  3659 "{_. _}" match any set comprehension as expected.  Potential
  3660 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3661 constant "_idtdummy" in the binding position.
  3662 
  3663 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3664 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3665 for example "A -> B" => "Pi A (%_. B)".
  3666 
  3667 * Pure: 'class_deps' command visualizes the subclass relation, using
  3668 the graph browser tool.
  3669 
  3670 * Pure: 'print_theory' now suppresses certain internal declarations by
  3671 default; use '!' option for full details.
  3672 
  3673 
  3674 *** HOL ***
  3675 
  3676 * Method "metis" proves goals by applying the Metis general-purpose
  3677 resolution prover (see also http://gilith.com/software/metis/).
  3678 Examples are in the directory MetisExamples.  WARNING: the
  3679 Isabelle/HOL-Metis integration does not yet work properly with
  3680 multi-threading.
  3681   
  3682 * Command 'sledgehammer' invokes external automatic theorem provers as
  3683 background processes.  It generates calls to the "metis" method if
  3684 successful. These can be pasted into the proof.  Users do not have to
  3685 wait for the automatic provers to return.  WARNING: does not really
  3686 work with multi-threading.
  3687 
  3688 * New "auto_quickcheck" feature tests outermost goal statements for
  3689 potential counter-examples.  Controlled by ML references
  3690 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3691 5000 milliseconds).  Fails silently if statements is outside of
  3692 executable fragment, or any other codgenerator problem occurs.
  3693 
  3694 * New constant "undefined" with axiom "undefined x = undefined".
  3695 
  3696 * Added class "HOL.eq", allowing for code generation with polymorphic
  3697 equality.
  3698 
  3699 * Some renaming of class constants due to canonical name prefixing in
  3700 the new 'class' package:
  3701 
  3702     HOL.abs ~> HOL.abs_class.abs
  3703     HOL.divide ~> HOL.divide_class.divide
  3704     0 ~> HOL.zero_class.zero
  3705     1 ~> HOL.one_class.one
  3706     op + ~> HOL.plus_class.plus
  3707     op - ~> HOL.minus_class.minus
  3708     uminus ~> HOL.minus_class.uminus
  3709     op * ~> HOL.times_class.times
  3710     op < ~> HOL.ord_class.less
  3711     op <= > HOL.ord_class.less_eq
  3712     Nat.power ~> Power.power_class.power
  3713     Nat.size ~> Nat.size_class.size
  3714     Numeral.number_of ~> Numeral.number_class.number_of
  3715     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3716     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3717     Orderings.min ~> Orderings.ord_class.min
  3718     Orderings.max ~> Orderings.ord_class.max
  3719     Divides.op div ~> Divides.div_class.div
  3720     Divides.op mod ~> Divides.div_class.mod
  3721     Divides.op dvd ~> Divides.div_class.dvd
  3722 
  3723 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3724 
  3725 a) User-defined constants using any of the names "plus", "minus",
  3726 "times", "less" or "less_eq". The standard syntax translations for
  3727 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3728 names.
  3729 
  3730 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3731 INCOMPATIBILITY: use more specific names.
  3732 
  3733 c) Permutative equations (e.g. "a + b = b + a")
  3734 Since the change of names also changes the order of terms, permutative
  3735 rewrite rules may get applied in a different order. Experience shows
  3736 that this is rarely the case (only two adaptions in the whole Isabelle
  3737 distribution).  INCOMPATIBILITY: rewrite proofs
  3738 
  3739 d) ML code directly refering to constant names
  3740 This in general only affects hand-written proof tactics, simprocs and
  3741 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3742 Consider using @{const_name} antiquotation.
  3743 
  3744 * New class "default" with associated constant "default".
  3745 
  3746 * Function "sgn" is now overloaded and available on int, real, complex
  3747 (and other numeric types), using class "sgn".  Two possible defs of
  3748 sgn are given as equational assumptions in the classes sgn_if and
  3749 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3750 INCOMPATIBILITY.
  3751 
  3752 * Locale "partial_order" now unified with class "order" (cf. theory
  3753 Orderings), added parameter "less".  INCOMPATIBILITY.
  3754 
  3755 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3756 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3757 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3758 
  3759 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3760 changed order of proof goals in instance proofs.
  3761 
  3762 * The transitivity reasoner for partial and linear orders is set up
  3763 for classes "order" and "linorder".  Instances of the reasoner are available
  3764 in all contexts importing or interpreting the corresponding locales.
  3765 Method "order" invokes the reasoner separately; the reasoner
  3766 is also integrated with the Simplifier as a solver.  Diagnostic
  3767 command 'print_orders' shows the available instances of the reasoner
  3768 in the current context.
  3769 
  3770 * Localized monotonicity predicate in theory "Orderings"; integrated
  3771 lemmas max_of_mono and min_of_mono with this predicate.
  3772 INCOMPATIBILITY.
  3773 
  3774 * Formulation of theorem "dense" changed slightly due to integration
  3775 with new class dense_linear_order.
  3776 
  3777 * Uniform lattice theory development in HOL.
  3778 
  3779     constants "meet" and "join" now named "inf" and "sup"
  3780     constant "Meet" now named "Inf"
  3781 
  3782     classes "meet_semilorder" and "join_semilorder" now named
  3783       "lower_semilattice" and "upper_semilattice"
  3784     class "lorder" now named "lattice"
  3785     class "comp_lat" now named "complete_lattice"
  3786 
  3787     Instantiation of lattice classes allows explicit definitions
  3788     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3789 
  3790   INCOMPATIBILITY.  Theorem renames:
  3791 
  3792     meet_left_le            ~> inf_le1
  3793     meet_right_le           ~> inf_le2
  3794     join_left_le            ~> sup_ge1
  3795     join_right_le           ~> sup_ge2
  3796     meet_join_le            ~> inf_sup_ord
  3797     le_meetI                ~> le_infI
  3798     join_leI                ~> le_supI
  3799     le_meet                 ~> le_inf_iff
  3800     le_join                 ~> ge_sup_conv
  3801     meet_idempotent         ~> inf_idem
  3802     join_idempotent         ~> sup_idem
  3803     meet_comm               ~> inf_commute
  3804     join_comm               ~> sup_commute
  3805     meet_leI1               ~> le_infI1
  3806     meet_leI2               ~> le_infI2
  3807     le_joinI1               ~> le_supI1
  3808     le_joinI2               ~> le_supI2
  3809     meet_assoc              ~> inf_assoc
  3810     join_assoc              ~> sup_assoc
  3811     meet_left_comm          ~> inf_left_commute
  3812     meet_left_idempotent    ~> inf_left_idem
  3813     join_left_comm          ~> sup_left_commute
  3814     join_left_idempotent    ~> sup_left_idem
  3815     meet_aci                ~> inf_aci
  3816     join_aci                ~> sup_aci
  3817     le_def_meet             ~> le_iff_inf
  3818     le_def_join             ~> le_iff_sup
  3819     join_absorp2            ~> sup_absorb2
  3820     join_absorp1            ~> sup_absorb1
  3821     meet_absorp1            ~> inf_absorb1
  3822     meet_absorp2            ~> inf_absorb2
  3823     meet_join_absorp        ~> inf_sup_absorb
  3824     join_meet_absorp        ~> sup_inf_absorb
  3825     distrib_join_le         ~> distrib_sup_le
  3826     distrib_meet_le         ~> distrib_inf_le
  3827 
  3828     add_meet_distrib_left   ~> add_inf_distrib_left
  3829     add_join_distrib_left   ~> add_sup_distrib_left
  3830     is_join_neg_meet        ~> is_join_neg_inf
  3831     is_meet_neg_join        ~> is_meet_neg_sup
  3832     add_meet_distrib_right  ~> add_inf_distrib_right
  3833     add_join_distrib_right  ~> add_sup_distrib_right
  3834     add_meet_join_distribs  ~> add_sup_inf_distribs
  3835     join_eq_neg_meet        ~> sup_eq_neg_inf
  3836     meet_eq_neg_join        ~> inf_eq_neg_sup
  3837     add_eq_meet_join        ~> add_eq_inf_sup
  3838     meet_0_imp_0            ~> inf_0_imp_0
  3839     join_0_imp_0            ~> sup_0_imp_0
  3840     meet_0_eq_0             ~> inf_0_eq_0
  3841     join_0_eq_0             ~> sup_0_eq_0
  3842     neg_meet_eq_join        ~> neg_inf_eq_sup
  3843     neg_join_eq_meet        ~> neg_sup_eq_inf
  3844     join_eq_if              ~> sup_eq_if
  3845 
  3846     mono_meet               ~> mono_inf
  3847     mono_join               ~> mono_sup
  3848     meet_bool_eq            ~> inf_bool_eq
  3849     join_bool_eq            ~> sup_bool_eq
  3850     meet_fun_eq             ~> inf_fun_eq
  3851     join_fun_eq             ~> sup_fun_eq
  3852     meet_set_eq             ~> inf_set_eq
  3853     join_set_eq             ~> sup_set_eq
  3854     meet1_iff               ~> inf1_iff
  3855     meet2_iff               ~> inf2_iff
  3856     meet1I                  ~> inf1I
  3857     meet2I                  ~> inf2I
  3858     meet1D1                 ~> inf1D1
  3859     meet2D1                 ~> inf2D1
  3860     meet1D2                 ~> inf1D2
  3861     meet2D2                 ~> inf2D2
  3862     meet1E                  ~> inf1E
  3863     meet2E                  ~> inf2E
  3864     join1_iff               ~> sup1_iff
  3865     join2_iff               ~> sup2_iff
  3866     join1I1                 ~> sup1I1
  3867     join2I1                 ~> sup2I1
  3868     join1I1                 ~> sup1I1
  3869     join2I2                 ~> sup1I2
  3870     join1CI                 ~> sup1CI
  3871     join2CI                 ~> sup2CI
  3872     join1E                  ~> sup1E
  3873     join2E                  ~> sup2E
  3874 
  3875     is_meet_Meet            ~> is_meet_Inf
  3876     Meet_bool_def           ~> Inf_bool_def
  3877     Meet_fun_def            ~> Inf_fun_def
  3878     Meet_greatest           ~> Inf_greatest
  3879     Meet_lower              ~> Inf_lower
  3880     Meet_set_def            ~> Inf_set_def
  3881 
  3882     Sup_def                 ~> Sup_Inf
  3883     Sup_bool_eq             ~> Sup_bool_def
  3884     Sup_fun_eq              ~> Sup_fun_def
  3885     Sup_set_eq              ~> Sup_set_def
  3886 
  3887     listsp_meetI            ~> listsp_infI
  3888     listsp_meet_eq          ~> listsp_inf_eq
  3889 
  3890     meet_min                ~> inf_min
  3891     join_max                ~> sup_max
  3892 
  3893 * Added syntactic class "size"; overloaded constant "size" now has
  3894 type "'a::size ==> bool"
  3895 
  3896 * Internal reorganisation of `size' of datatypes: size theorems
  3897 "foo.size" are no longer subsumed by "foo.simps" (but are still
  3898 simplification rules by default!); theorems "prod.size" now named
  3899 "*.size".
  3900 
  3901 * Class "div" now inherits from class "times" rather than "type".
  3902 INCOMPATIBILITY.
  3903 
  3904 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  3905 Linorder etc.  have disappeared; operations defined in terms of
  3906 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  3907 
  3908 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  3909 
  3910 * HOL-Word: New extensive library and type for generic, fixed size
  3911 machine words, with arithemtic, bit-wise, shifting and rotating
  3912 operations, reflection into int, nat, and bool lists, automation for
  3913 linear arithmetic (by automatic reflection into nat or int), including
  3914 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  3915 arithmetic type classes, supporting automatic simplification of
  3916 numerals on all operations.
  3917 
  3918 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  3919 
  3920 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  3921 
  3922 * Code generator library theories:
  3923   - Code_Integer represents HOL integers by big integer literals in target
  3924     languages.
  3925   - Code_Char represents HOL characters by character literals in target
  3926     languages.
  3927   - Code_Char_chr like Code_Char, but also offers treatment of character
  3928     codes; includes Code_Integer.
  3929   - Executable_Set allows to generate code for finite sets using lists.
  3930   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  3931     denominator).
  3932   - Executable_Real implements a subset of real numbers, namly those
  3933     representable by rational numbers.
  3934   - Efficient_Nat implements natural numbers by integers, which in general will
  3935     result in higher efficency; pattern matching with 0/Suc is eliminated;
  3936     includes Code_Integer.
  3937   - Code_Index provides an additional datatype index which is mapped to
  3938     target-language built-in integers.
  3939   - Code_Message provides an additional datatype message_string which is isomorphic to
  3940     strings; messages are mapped to target-language strings.
  3941 
  3942 * New package for inductive predicates
  3943 
  3944   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  3945 
  3946     inductive
  3947       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3948       for z_1 :: U_1 and ... and z_n :: U_m
  3949     where
  3950       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3951     | ...
  3952 
  3953   with full support for type-inference, rather than
  3954 
  3955     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3956 
  3957     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3958     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3959 
  3960     inductive "s z_1 ... z_m"
  3961     intros
  3962       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3963       ...
  3964 
  3965   For backward compatibility, there is a wrapper allowing inductive
  3966   sets to be defined with the new package via
  3967 
  3968     inductive_set
  3969       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3970       for z_1 :: U_1 and ... and z_n :: U_m
  3971     where
  3972       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3973     | ...
  3974 
  3975   or
  3976 
  3977     inductive_set
  3978       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3979       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3980       for z_1 :: U_1 and ... and z_n :: U_m
  3981     where
  3982       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3983     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3984     | ...
  3985 
  3986   if the additional syntax "p ..." is required.
  3987 
  3988   Numerous examples can be found in the subdirectories src/HOL/Auth,
  3989   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  3990 
  3991   INCOMPATIBILITIES:
  3992 
  3993   - Since declaration and definition of inductive sets or predicates
  3994     is no longer separated, abbreviations involving the newly
  3995     introduced sets or predicates must be specified together with the
  3996     introduction rules after the 'where' keyword (see above), rather
  3997     than before the actual inductive definition.
  3998 
  3999   - The variables in induction and elimination rules are now
  4000     quantified in the order of their occurrence in the introduction
  4001     rules, rather than in alphabetical order. Since this may break
  4002     some proofs, these proofs either have to be repaired, e.g. by
  4003     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  4004     statements of the form
  4005 
  4006       case (rule_i a_i_1 ... a_i_{k_i})
  4007 
  4008     or the old order of quantification has to be restored by explicitly adding
  4009     meta-level quantifiers in the introduction rules, i.e.
  4010 
  4011       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  4012 
  4013   - The format of the elimination rules is now
  4014 
  4015       p z_1 ... z_m x_1 ... x_n ==>
  4016         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4017         ==> ... ==> P
  4018 
  4019     for predicates and
  4020 
  4021       (x_1, ..., x_n) : s z_1 ... z_m ==>
  4022         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4023         ==> ... ==> P
  4024 
  4025     for sets rather than
  4026 
  4027       x : s z_1 ... z_m ==>
  4028         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  4029         ==> ... ==> P
  4030 
  4031     This may require terms in goals to be expanded to n-tuples
  4032     (e.g. using case_tac or simplification with the split_paired_all
  4033     rule) before the above elimination rule is applicable.
  4034 
  4035   - The elimination or case analysis rules for (mutually) inductive
  4036     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  4037     list of rules "p_1_..._p_k.elims" is no longer available.
  4038 
  4039 * New package "function"/"fun" for general recursive functions,
  4040 supporting mutual and nested recursion, definitions in local contexts,
  4041 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  4042 for small examples, and the separate tutorial on the function
  4043 package. The old recdef "package" is still available as before, but
  4044 users are encouraged to use the new package.
  4045 
  4046 * Method "lexicographic_order" automatically synthesizes termination
  4047 relations as lexicographic combinations of size measures. 
  4048 
  4049 * Case-expressions allow arbitrary constructor-patterns (including
  4050 "_") and take their order into account, like in functional
  4051 programming.  Internally, this is translated into nested
  4052 case-expressions; missing cases are added and mapped to the predefined
  4053 constant "undefined". In complicated cases printing may no longer show
  4054 the original input but the internal form. Lambda-abstractions allow
  4055 the same form of pattern matching: "% pat1 => e1 | ..." is an
  4056 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  4057 variable.
  4058 
  4059 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  4060 is an abbreviation for "of_nat :: nat => int". The simplification
  4061 rules for "of_nat" have been changed to work like "int" did
  4062 previously.  Potential INCOMPATIBILITY:
  4063   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  4064   - of_nat_diff and of_nat_mult are no longer default simp rules
  4065 
  4066 * Method "algebra" solves polynomial equations over (semi)rings using
  4067 Groebner bases. The (semi)ring structure is defined by locales and the
  4068 tool setup depends on that generic context. Installing the method for
  4069 a specific type involves instantiating the locale and possibly adding
  4070 declarations for computation on the coefficients.  The method is
  4071 already instantiated for natural numbers and for the axiomatic class
  4072 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  4073 CALCULEMUS 2007 for the general principles underlying this
  4074 architecture of context-aware proof-tools.
  4075 
  4076 * Method "ferrack" implements quantifier elimination over
  4077 special-purpose dense linear orders using locales (analogous to
  4078 "algebra"). The method is already installed for class
  4079 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  4080 rat, etc.
  4081 
  4082 * Former constant "List.op @" now named "List.append".  Use ML
  4083 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  4084 circumvent possible incompatibilities when working on ML level.
  4085 
  4086 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  4087 
  4088 * New function listsum :: 'a list => 'a for arbitrary monoids.
  4089 Special syntax: "SUM x <- xs. f x" (and latex variants)
  4090 
  4091 * New syntax for Haskell-like list comprehension (input only), eg.
  4092 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  4093 
  4094 * The special syntax for function "filter" has changed from [x :
  4095 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  4096 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  4097 
  4098 * [a..b] is now defined for arbitrary linear orders.  It used to be
  4099 defined on nat only, as an abbreviation for [a..<Suc b]
  4100 INCOMPATIBILITY.
  4101 
  4102 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  4103 
  4104 * New functions "sorted" and "sort" in src/HOL/List.thy.
  4105 
  4106 * New lemma collection field_simps (an extension of ring_simps) for
  4107 manipulating (in)equations involving division. Multiplies with all
  4108 denominators that can be proved to be non-zero (in equations) or
  4109 positive/negative (in inequations).
  4110 
  4111 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  4112 have been improved and renamed to ring_simps, group_simps and
  4113 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  4114 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  4115 
  4116 * Theory Library/Commutative_Ring: switched from recdef to function
  4117 package; constants add, mul, pow now curried.  Infix syntax for
  4118 algebraic operations.
  4119 
  4120 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  4121 INCOMPATIBILITY.
  4122 
  4123 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  4124 INCOMPATIBILITY.
  4125 
  4126 * HOL/records: generalised field-update to take a function on the
  4127 field rather than the new value: r(|A := x|) is translated to A_update
  4128 (K x) r The K-combinator that is internally used is called K_record.
  4129 INCOMPATIBILITY: Usage of the plain update functions has to be
  4130 adapted.
  4131  
  4132 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  4133 * x = 0, which are required for a semiring.  Richer structures do not
  4134 inherit from semiring_0 anymore, because this property is a theorem
  4135 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  4136 there is more to prove, but this is mostly trivial.
  4137 
  4138 * Class "recpower" is generalized to arbitrary monoids, not just
  4139 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  4140 commutativity or semiring properties additionally.
  4141 
  4142 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  4143 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  4144 better use 'abbreviation'.
  4145 
  4146 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  4147 
  4148 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  4149 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  4150 significant changes for setting up numeral syntax for types:
  4151   - New constants Numeral.pred and Numeral.succ instead
  4152       of former Numeral.bin_pred and Numeral.bin_succ.
  4153   - Use integer operations instead of bin_add, bin_mult and so on.
  4154   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  4155   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  4156 
  4157 See src/HOL/Integ/IntArith.thy for an example setup.
  4158 
  4159 * Command 'normal_form' computes the normal form of a term that may
  4160 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  4161 produces ``[b, c, a]'' (without proof).  This command is suitable for
  4162 heavy-duty computations because the functions are compiled to ML
  4163 first.  Correspondingly, a method "normalization" is provided.  See
  4164 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  4165 
  4166 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  4167 25 like -->); output depends on the "iff" print_mode, the default is
  4168 "A = B" (with priority 50).
  4169 
  4170 * Relations less (<) and less_eq (<=) are also available on type bool.
  4171 Modified syntax to disallow nesting without explicit parentheses,
  4172 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  4173 INCOMPATIBILITY.
  4174 
  4175 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  4176 
  4177 * Relation composition operator "op O" now has precedence 75 and binds
  4178 stronger than union and intersection. INCOMPATIBILITY.
  4179 
  4180 * The old set interval syntax "{m..n(}" (and relatives) has been
  4181 removed.  Use "{m..<n}" (and relatives) instead.
  4182 
  4183 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  4184 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  4185 ``declare [[simproc del: neq]]''.
  4186 
  4187 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  4188 True/False.
  4189 
  4190 * Theorem Cons_eq_map_conv no longer declared as "simp".
  4191 
  4192 * Theorem setsum_mult renamed to setsum_right_distrib.
  4193 
  4194 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  4195 ``rule'' method.
  4196 
  4197 * Reimplemented methods "sat" and "satx", with several improvements:
  4198 goals no longer need to be stated as "<prems> ==> False", equivalences
  4199 (i.e. "=" on type bool) are handled, variable names of the form
  4200 "lit_<n>" are no longer reserved, significant speedup.
  4201 
  4202 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  4203 zChaff is still supported as well.
  4204 
  4205 * 'inductive' and 'datatype': provide projections of mutual rules,
  4206 bundled as foo_bar.inducts;
  4207 
  4208 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  4209 Library.
  4210 
  4211 * Library: moved theory Accessible_Part to main HOL.
  4212 
  4213 * Library: added theory Coinductive_List of potentially infinite lists
  4214 as greatest fixed-point.
  4215 
  4216 * Library: added theory AssocList which implements (finite) maps as
  4217 association lists.
  4218 
  4219 * Method "evaluation" solves goals (i.e. a boolean expression)
  4220 efficiently by compiling it to ML.  The goal is "proved" (via an
  4221 oracle) if it evaluates to True.
  4222 
  4223 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  4224 also when invoked by the simplifier.  This results in the Simplifier
  4225 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  4226 Configuration option fast_arith_split_limit=0 recovers the old
  4227 behavior.
  4228 
  4229 * Support for hex (0x20) and binary (0b1001) numerals.
  4230 
  4231 * New method: reify eqs (t), where eqs are equations for an
  4232 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  4233 parameter, computes a term s::'b and a list xs::'a list and proves the
  4234 theorem I xs s = t. This is also known as reification or quoting. The
  4235 resulting theorem is applied to the subgoal to substitute t with I xs
  4236 s.  If t is omitted, the subgoal itself is reified.
  4237 
  4238 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  4239 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  4240 where f is supposed to be a computable function (in the sense of code
  4241 generattion). The method uses reify to compute s and xs as above then
  4242 applies corr_thm and uses normalization by evaluation to "prove" f s =
  4243 r and finally gets the theorem t = r, which is again applied to the
  4244 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  4245 
  4246 * Reflection: Automatic reification now handels binding, an example is
  4247 available in src/HOL/ex/ReflectionEx.thy
  4248 
  4249 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  4250 command 'statespace' that is similar to 'record', but introduces an
  4251 abstract specification based on the locale infrastructure instead of
  4252 HOL types.  This leads to extra flexibility in composing state spaces,
  4253 in particular multiple inheritance and renaming of components.
  4254 
  4255 
  4256 *** HOL-Complex ***
  4257 
  4258 * Hyperreal: Functions root and sqrt are now defined on negative real
  4259 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  4260 Nonnegativity side conditions have been removed from many lemmas, so
  4261 that more subgoals may now be solved by simplification; potential
  4262 INCOMPATIBILITY.
  4263 
  4264 * Real: new type classes formalize real normed vector spaces and
  4265 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  4266 and norm :: 'a => real.
  4267 
  4268 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  4269 reals into other types. The overloaded constant Reals :: 'a set is now
  4270 defined as range of_real; potential INCOMPATIBILITY.
  4271 
  4272 * Real: proper support for ML code generation, including 'quickcheck'.
  4273 Reals are implemented as arbitrary precision rationals.
  4274 
  4275 * Hyperreal: Several constants that previously worked only for the
  4276 reals have been generalized, so they now work over arbitrary vector
  4277 spaces. Type annotations may need to be added in some cases; potential
  4278 INCOMPATIBILITY.
  4279 
  4280   Infinitesimal  :: ('a::real_normed_vector) star set
  4281   HFinite        :: ('a::real_normed_vector) star set
  4282   HInfinite      :: ('a::real_normed_vector) star set
  4283   approx         :: ('a::real_normed_vector) star => 'a star => bool
  4284   monad          :: ('a::real_normed_vector) star => 'a star set
  4285   galaxy         :: ('a::real_normed_vector) star => 'a star set
  4286   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  4287   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  4288   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  4289   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  4290   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  4291   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  4292   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  4293   sgn            :: 'a::real_normed_vector => 'a
  4294   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  4295 
  4296 * Complex: Some complex-specific constants are now abbreviations for
  4297 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  4298 hnorm.  Other constants have been entirely removed in favor of the
  4299 polymorphic versions (INCOMPATIBILITY):
  4300 
  4301   approx        <-- capprox
  4302   HFinite       <-- CFinite
  4303   HInfinite     <-- CInfinite
  4304   Infinitesimal <-- CInfinitesimal
  4305   monad         <-- cmonad
  4306   galaxy        <-- cgalaxy
  4307   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  4308   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  4309   (ns)deriv     <-- (ns)cderiv
  4310 
  4311 
  4312 *** HOL-Algebra ***
  4313 
  4314 * Formalisation of ideals and the quotient construction over rings.
  4315 
  4316 * Order and lattice theory no longer based on records.
  4317 INCOMPATIBILITY.
  4318 
  4319 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  4320 greatest_closed.  INCOMPATIBILITY.
  4321 
  4322 * Method algebra is now set up via an attribute.  For examples see
  4323 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  4324 of algebraic structures.
  4325 
  4326 * Renamed theory CRing to Ring.
  4327 
  4328 
  4329 *** HOL-Nominal ***
  4330 
  4331 * Substantial, yet incomplete support for nominal datatypes (binding
  4332 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  4333 src/HOL/Nominal/Examples.  Prospective users should consult
  4334 http://isabelle.in.tum.de/nominal/
  4335 
  4336 
  4337 *** ML ***
  4338 
  4339 * ML basics: just one true type int, which coincides with IntInf.int
  4340 (even on SML/NJ).
  4341 
  4342 * ML within Isar: antiquotations allow to embed statically-checked
  4343 formal entities in the source, referring to the context available at
  4344 compile-time.  For example:
  4345 
  4346 ML {* @{sort "{zero,one}"} *}
  4347 ML {* @{typ "'a => 'b"} *}
  4348 ML {* @{term "%x. x"} *}
  4349 ML {* @{prop "x == y"} *}
  4350 ML {* @{ctyp "'a => 'b"} *}
  4351 ML {* @{cterm "%x. x"} *}
  4352 ML {* @{cprop "x == y"} *}
  4353 ML {* @{thm asm_rl} *}
  4354 ML {* @{thms asm_rl} *}
  4355 ML {* @{type_name c} *}
  4356 ML {* @{type_syntax c} *}
  4357 ML {* @{const_name c} *}
  4358 ML {* @{const_syntax c} *}
  4359 ML {* @{context} *}
  4360 ML {* @{theory} *}
  4361 ML {* @{theory Pure} *}
  4362 ML {* @{theory_ref} *}
  4363 ML {* @{theory_ref Pure} *}
  4364 ML {* @{simpset} *}
  4365 ML {* @{claset} *}
  4366 ML {* @{clasimpset} *}
  4367 
  4368 The same works for sources being ``used'' within an Isar context.
  4369 
  4370 * ML in Isar: improved error reporting; extra verbosity with
  4371 ML_Context.trace enabled.
  4372 
  4373 * Pure/General/table.ML: the join operations now works via exceptions
  4374 DUP/SAME instead of type option. This is simpler in simple cases, and
  4375 admits slightly more efficient complex applications.
  4376 
  4377 * Pure: 'advanced' translation functions (parse_translation etc.) now
  4378 use Context.generic instead of just theory.
  4379 
  4380 * Pure: datatype Context.generic joins theory/Proof.context and
  4381 provides some facilities for code that works in either kind of
  4382 context, notably GenericDataFun for uniform theory and proof data.
  4383 
  4384 * Pure: simplified internal attribute type, which is now always
  4385 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  4386 local (Proof.context) attributes have been discontinued, while
  4387 minimizing code duplication. Thm.rule_attribute and
  4388 Thm.declaration_attribute build canonical attributes; see also structure
  4389 Context for further operations on Context.generic, notably
  4390 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  4391 declarations and definitions.
  4392 
  4393 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  4394 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  4395 init only required for impure data. INCOMPATIBILITY: empty really need
  4396 to be empty (no dependencies on theory content!)
  4397 
  4398 * Pure/kernel: consts certification ignores sort constraints given in
  4399 signature declarations. (This information is not relevant to the
  4400 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  4401 potential INCOMPATIBILITY.
  4402 
  4403 * Pure: axiomatic type classes are now purely definitional, with
  4404 explicit proofs of class axioms and super class relations performed
  4405 internally. See Pure/axclass.ML for the main internal interfaces --
  4406 notably AxClass.define_class supercedes AxClass.add_axclass, and
  4407 AxClass.axiomatize_class/classrel/arity supersede
  4408 Sign.add_classes/classrel/arities.
  4409 
  4410 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  4411 global/local versions on theory vs. Proof.context have been
  4412 discontinued; Attrib.syntax and Method.syntax have been adapted
  4413 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  4414 attributes, methods, etc.
  4415 
  4416 * Pure: several functions of signature "... -> theory -> theory * ..."
  4417 have been reoriented to "... -> theory -> ... * theory" in order to
  4418 allow natural usage in combination with the ||>, ||>>, |-> and
  4419 fold_map combinators.
  4420 
  4421 * Pure: official theorem names (closed derivations) and additional
  4422 comments (tags) are now strictly separate.  Name hints -- which are
  4423 maintained as tags -- may be attached any time without affecting the
  4424 derivation.
  4425 
  4426 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  4427 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  4428 achieve the old behaviour.
  4429 
  4430 * Pure: the "Goal" constant is now called "prop", supporting a
  4431 slightly more general idea of ``protecting'' meta-level rule
  4432 statements.
  4433 
  4434 * Pure: Logic.(un)varify only works in a global context, which is now
  4435 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  4436 Logic.legacy_(un)varify as temporary workaround.
  4437 
  4438 * Pure: structure Name provides scalable operations for generating
  4439 internal variable names, notably Name.variants etc.  This replaces
  4440 some popular functions from term.ML:
  4441 
  4442   Term.variant		->  Name.variant
  4443   Term.variantlist	->  Name.variant_list
  4444   Term.invent_names	->  Name.invent_list
  4445 
  4446 Note that low-level renaming rarely occurs in new code -- operations
  4447 from structure Variable are used instead (see below).
  4448 
  4449 * Pure: structure Variable provides fundamental operations for proper
  4450 treatment of fixed/schematic variables in a context.  For example,
  4451 Variable.import introduces fixes for schematics of given facts and
  4452 Variable.export reverses the effect (up to renaming) -- this replaces
  4453 various freeze_thaw operations.
  4454 
  4455 * Pure: structure Goal provides simple interfaces for
  4456 init/conclude/finish and tactical prove operations (replacing former
  4457 Tactic.prove).  Goal.prove is the canonical way to prove results
  4458 within a given context; Goal.prove_global is a degraded version for
  4459 theory level goals, including a global Drule.standard.  Note that
  4460 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  4461 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  4462 in a locale context).
  4463 
  4464 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  4465 and type checking (Syntax.check_term etc.), with common combinations
  4466 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  4467 which are considered legacy and await removal.
  4468 
  4469 * Pure/Syntax: generic interfaces for type unchecking
  4470 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  4471 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  4472 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  4473 available for convenience, but refer to the very same operations using
  4474 a mere theory instead of a full context.
  4475 
  4476 * Isar: simplified treatment of user-level errors, using exception
  4477 ERROR of string uniformly.  Function error now merely raises ERROR,
  4478 without any side effect on output channels.  The Isar toplevel takes
  4479 care of proper display of ERROR exceptions.  ML code may use plain
  4480 handle/can/try; cat_error may be used to concatenate errors like this:
  4481 
  4482   ... handle ERROR msg => cat_error msg "..."
  4483 
  4484 Toplevel ML code (run directly or through the Isar toplevel) may be
  4485 embedded into the Isar toplevel with exception display/debug like
  4486 this:
  4487 
  4488   Isar.toplevel (fn () => ...)
  4489 
  4490 INCOMPATIBILITY, removed special transform_error facilities, removed
  4491 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  4492 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  4493 -- use plain ERROR instead.
  4494 
  4495 * Isar: theory setup now has type (theory -> theory), instead of a
  4496 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  4497 
  4498 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  4499 ProofContext.debug/verbose flags.
  4500 
  4501 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  4502 theory before entering a proof state.  Transactions now always see a
  4503 quasi-functional intermediate checkpoint, both in interactive and
  4504 batch mode.
  4505 
  4506 * Isar: simplified interfaces for outer syntax.  Renamed
  4507 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  4508 OuterSyntax.add_parsers -- this functionality is now included in
  4509 OuterSyntax.command etc.  INCOMPATIBILITY.
  4510 
  4511 * Simplifier: the simpset of a running simplification process now
  4512 contains a proof context (cf. Simplifier.the_context), which is the
  4513 very context that the initial simpset has been retrieved from (by
  4514 simpset_of/local_simpset_of).  Consequently, all plug-in components
  4515 (solver, looper etc.) may depend on arbitrary proof data.
  4516 
  4517 * Simplifier.inherit_context inherits the proof context (plus the
  4518 local bounds) of the current simplification process; any simproc
  4519 etc. that calls the Simplifier recursively should do this!  Removed
  4520 former Simplifier.inherit_bounds, which is already included here --
  4521 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  4522 specify an explicit context using Simplifier.context/theory_context.
  4523 
  4524 * Simplifier/Classical Reasoner: more abstract interfaces
  4525 change_simpset/claset for modifying the simpset/claset reference of a
  4526 theory; raw versions simpset/claset_ref etc. have been discontinued --
  4527 INCOMPATIBILITY.
  4528 
  4529 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  4530 "Trueprop" etc.
  4531 
  4532 
  4533 *** System ***
  4534 
  4535 * settings: the default heap location within ISABELLE_HOME_USER now
  4536 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  4537 Isabelle installations.
  4538 
  4539 * isabelle-process: option -S (secure mode) disables some critical
  4540 operations, notably runtime compilation and evaluation of ML source
  4541 code.
  4542 
  4543 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  4544 
  4545 * Support for parallel execution, using native multicore support of
  4546 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  4547 independent theories, according to the given theory header
  4548 specifications. The maximum number of worker threads is specified via
  4549 usedir option -M or the "max-threads" setting in Proof General. A
  4550 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  4551 to 6 on a 8-core machine.  User-code needs to observe certain
  4552 guidelines for thread-safe programming, see appendix A in the Isar
  4553 Implementation manual.
  4554 
  4555 
  4556 
  4557 New in Isabelle2005 (October 2005)
  4558 ----------------------------------
  4559 
  4560 *** General ***
  4561 
  4562 * Theory headers: the new header syntax for Isar theories is
  4563 
  4564   theory <name>
  4565   imports <theory1> ... <theoryN>
  4566   uses <file1> ... <fileM>
  4567   begin
  4568 
  4569 where the 'uses' part is optional.  The previous syntax
  4570 
  4571   theory <name> = <theory1> + ... + <theoryN>:
  4572 
  4573 will disappear in the next release.  Use isatool fixheaders to convert
  4574 existing theory files.  Note that there is no change in ancient
  4575 non-Isar theories now, but these will disappear soon.
  4576 
  4577 * Theory loader: parent theories can now also be referred to via
  4578 relative and absolute paths.
  4579 
  4580 * Command 'find_theorems' searches for a list of criteria instead of a
  4581 list of constants. Known criteria are: intro, elim, dest, name:string,
  4582 simp:term, and any term. Criteria can be preceded by '-' to select
  4583 theorems that do not match. Intro, elim, dest select theorems that
  4584 match the current goal, name:s selects theorems whose fully qualified
  4585 name contain s, and simp:term selects all simplification rules whose
  4586 lhs match term.  Any other term is interpreted as pattern and selects
  4587 all theorems matching the pattern. Available in ProofGeneral under
  4588 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  4589 
  4590   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  4591 
  4592 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  4593 matching the current goal as introduction rule and not having "HOL."
  4594 in their name (i.e. not being defined in theory HOL).
  4595 
  4596 * Command 'thms_containing' has been discontinued in favour of
  4597 'find_theorems'; INCOMPATIBILITY.
  4598 
  4599 * Communication with Proof General is now 8bit clean, which means that
  4600 Unicode text in UTF-8 encoding may be used within theory texts (both
  4601 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4602 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4603 
  4604   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4605   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4606 
  4607 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4608 Classical Reasoner.  Typical big applications run around 2 times
  4609 faster.
  4610 
  4611 
  4612 *** Document preparation ***
  4613 
  4614 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4615 of raw sources.  Only those symbols that do not require additional
  4616 LaTeX packages (depending on comments in isabellesym.sty) are
  4617 displayed properly, everything else is left verbatim.  isatool display
  4618 and isatool print are used as front ends (these are subject to the
  4619 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4620 
  4621 * Command tags control specific markup of certain regions of text,
  4622 notably folding and hiding.  Predefined tags include "theory" (for
  4623 theory begin and end), "proof" for proof commands, and "ML" for
  4624 commands involving ML code; the additional tags "visible" and
  4625 "invisible" are unused by default.  Users may give explicit tag
  4626 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4627 interpretation of tags is determined by the LaTeX job during document
  4628 preparation: see option -V of isatool usedir, or options -n and -t of
  4629 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4630 \isadroptag.
  4631 
  4632 Several document versions may be produced at the same time via isatool
  4633 usedir (the generated index.html will link all of them).  Typical
  4634 specifications include ''-V document=theory,proof,ML'' to present
  4635 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4636 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4637 these parts without any formal replacement text.  The Isabelle site
  4638 default settings produce ''document'' and ''outline'' versions as
  4639 specified above.
  4640 
  4641 * Several new antiquotations:
  4642 
  4643   @{term_type term} prints a term with its type annotated;
  4644 
  4645   @{typeof term} prints the type of a term;
  4646 
  4647   @{const const} is the same as @{term const}, but checks that the
  4648   argument is a known logical constant;
  4649 
  4650   @{term_style style term} and @{thm_style style thm} print a term or
  4651   theorem applying a "style" to it
  4652 
  4653   @{ML text}
  4654 
  4655 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4656 definitions, equations, inequations etc., 'concl' printing only the
  4657 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4658 to print the specified premise.  TermStyle.add_style provides an ML
  4659 interface for introducing further styles.  See also the "LaTeX Sugar"
  4660 document practical applications.  The ML antiquotation prints
  4661 type-checked ML expressions verbatim.
  4662 
  4663 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4664 and 'text' support optional locale specification '(in loc)', which
  4665 specifies the default context for interpreting antiquotations.  For
  4666 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4667 
  4668 * Option 'locale=NAME' of antiquotations specifies an alternative
  4669 context interpreting the subsequent argument.  For example: @{thm
  4670 [locale=lattice] inf_assoc}.
  4671 
  4672 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4673 a proof context.
  4674 
  4675 * Proper output of antiquotations for theory commands involving a
  4676 proof context (such as 'locale' or 'theorem (in loc) ...').
  4677 
  4678 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4679 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4680 
  4681 * isatool usedir: new option -C (default true) controls whether option
  4682 -D should include a copy of the original document directory; -C false
  4683 prevents unwanted effects such as copying of administrative CVS data.
  4684 
  4685 
  4686 *** Pure ***
  4687 
  4688 * Considerably improved version of 'constdefs' command.  Now performs
  4689 automatic type-inference of declared constants; additional support for
  4690 local structure declarations (cf. locales and HOL records), see also
  4691 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4692 sequential dependencies of definitions within a single 'constdefs'
  4693 section; moreover, the declared name needs to be an identifier.  If
  4694 all fails, consider to fall back on 'consts' and 'defs' separately.
  4695 
  4696 * Improved indexed syntax and implicit structures.  First of all,
  4697 indexed syntax provides a notational device for subscripted
  4698 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4699 expressions.  Secondly, in a local context with structure
  4700 declarations, number indexes \<^sub>n or the empty index (default
  4701 number 1) refer to a certain fixed variable implicitly; option
  4702 show_structs controls printing of implicit structures.  Typical
  4703 applications of these concepts involve record types and locales.
  4704 
  4705 * New command 'no_syntax' removes grammar declarations (and
  4706 translations) resulting from the given syntax specification, which is
  4707 interpreted in the same manner as for the 'syntax' command.
  4708 
  4709 * 'Advanced' translation functions (parse_translation etc.) may depend
  4710 on the signature of the theory context being presently used for
  4711 parsing/printing, see also isar-ref manual.
  4712 
  4713 * Improved 'oracle' command provides a type-safe interface to turn an
  4714 ML expression of type theory -> T -> term into a primitive rule of
  4715 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4716 is already included here); see also FOL/ex/IffExample.thy;
  4717 INCOMPATIBILITY.
  4718 
  4719 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4720 before); "cI" is no longer bound, use "c.intro" instead.
  4721 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4722 axclasses vs. locales.
  4723 
  4724 * Improved internal renaming of symbolic identifiers -- attach primes
  4725 instead of base 26 numbers.
  4726 
  4727 * New flag show_question_marks controls printing of leading question
  4728 marks in schematic variable names.
  4729 
  4730 * In schematic variable names, *any* symbol following \<^isub> or
  4731 \<^isup> is now treated as part of the base name.  For example, the
  4732 following works without printing of awkward ".0" indexes:
  4733 
  4734   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4735     by simp
  4736 
  4737 * Inner syntax includes (*(*nested*) comments*).
  4738 
  4739 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4740 annotations as "(00...)".
  4741 
  4742 * Clear separation of logical types and nonterminals, where the latter
  4743 may only occur in 'syntax' specifications or type abbreviations.
  4744 Before that distinction was only partially implemented via type class
  4745 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4746 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4747 exotic syntax specifications may require further adaption
  4748 (e.g. Cube/Cube.thy).
  4749 
  4750 * Removed obsolete type class "logic", use the top sort {} instead.
  4751 Note that non-logical types should be declared as 'nonterminals'
  4752 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4753 specifications.
  4754 
  4755 * Attributes 'induct' and 'cases': type or set names may now be
  4756 locally fixed variables as well.
  4757 
  4758 * Simplifier: can now control the depth to which conditional rewriting
  4759 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4760 Limit.
  4761 
  4762 * Simplifier: simplification procedures may now take the current
  4763 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4764 interface), which is very useful for calling the Simplifier
  4765 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4766 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4767 low-level mk_simproc no longer applies Logic.varify internally, to
  4768 allow for use in a context of fixed variables.
  4769 
  4770 * thin_tac now works even if the assumption being deleted contains !!
  4771 or ==>.  More generally, erule now works even if the major premise of
  4772 the elimination rule contains !! or ==>.
  4773 
  4774 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4775 
  4776 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4777 from Pure, which contains all common declarations already.  Both
  4778 theories are defined via plain Isabelle/Isar .thy files.
  4779 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4780 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4781 use isatool fixcpure to adapt your theory and ML sources.
  4782 
  4783 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4784 selections of theorems in named facts via index ranges.
  4785 
  4786 * 'print_theorems': in theory mode, really print the difference
  4787 wrt. the last state (works for interactive theory development only),
  4788 in proof mode print all local facts (cf. 'print_facts');
  4789 
  4790 * 'hide': option '(open)' hides only base names.
  4791 
  4792 * More efficient treatment of intermediate checkpoints in interactive
  4793 theory development.
  4794 
  4795 * Code generator is now invoked via code_module (incremental code
  4796 generation) and code_library (modular code generation, ML structures
  4797 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4798 must be quoted when used as identifiers.
  4799 
  4800 * New 'value' command for reading, evaluating and printing terms using
  4801 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4802 quoted when used as identifier.
  4803 
  4804 
  4805 *** Locales ***
  4806 
  4807 * New commands for the interpretation of locale expressions in
  4808 theories (1), locales (2) and proof contexts (3).  These generate
  4809 proof obligations from the expression specification.  After the
  4810 obligations have been discharged, theorems of the expression are added
  4811 to the theory, target locale or proof context.  The synopsis of the
  4812 commands is a follows:
  4813 
  4814   (1) interpretation expr inst
  4815   (2) interpretation target < expr
  4816   (3) interpret expr inst
  4817 
  4818 Interpretation in theories and proof contexts require a parameter
  4819 instantiation of terms from the current context.  This is applied to
  4820 specifications and theorems of the interpreted expression.
  4821 Interpretation in locales only permits parameter renaming through the
  4822 locale expression.  Interpretation is smart in that interpretations
  4823 that are active already do not occur in proof obligations, neither are
  4824 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4825 inspect active interpretations of a particular locale.  For details,
  4826 see the Isar Reference manual.  Examples can be found in
  4827 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4828 
  4829 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4830 'interpret' instead.
  4831 
  4832 * New context element 'constrains' for adding type constraints to
  4833 parameters.
  4834 
  4835 * Context expressions: renaming of parameters with syntax
  4836 redeclaration.
  4837 
  4838 * Locale declaration: 'includes' disallowed.
  4839 
  4840 * Proper static binding of attribute syntax -- i.e. types / terms /
  4841 facts mentioned as arguments are always those of the locale definition
  4842 context, independently of the context of later invocations.  Moreover,
  4843 locale operations (renaming and type / term instantiation) are applied
  4844 to attribute arguments as expected.
  4845 
  4846 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4847 actual attributes; rare situations may require Attrib.attribute to
  4848 embed those attributes into Attrib.src that lack concrete syntax.
  4849 Attribute implementations need to cooperate properly with the static
  4850 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4851 Attrib.XXX_thm etc. already do the right thing without further
  4852 intervention.  Only unusual applications -- such as "where" or "of"
  4853 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4854 on the context and the facts involved -- may have to assign parsed
  4855 values to argument tokens explicitly.
  4856 
  4857 * Changed parameter management in theorem generation for long goal
  4858 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4859 theorem statement in rare situations.
  4860 
  4861 * Locale inspection command 'print_locale' omits notes elements.  Use
  4862 'print_locale!' to have them included in the output.
  4863 
  4864 
  4865 *** Provers ***
  4866 
  4867 * Provers/hypsubst.ML: improved version of the subst method, for
  4868 single-step rewriting: it now works in bound variable contexts. New is
  4869 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  4870 rewrite a different subterm than the original subst method, which is
  4871 still available as 'simplesubst'.
  4872 
  4873 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  4874 and quasi orders.
  4875 
  4876 * Provers/trancl.ML: new transitivity reasoner for transitive and
  4877 reflexive-transitive closure of relations.
  4878 
  4879 * Provers/blast.ML: new reference depth_limit to make blast's depth
  4880 limit (previously hard-coded with a value of 20) user-definable.
  4881 
  4882 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  4883 is peformed already.  Object-logics merely need to finish their
  4884 initial simpset configuration as before.  INCOMPATIBILITY.
  4885 
  4886 
  4887 *** HOL ***
  4888 
  4889 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  4890 
  4891   syntax (epsilon)
  4892     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  4893 
  4894 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  4895 and x-symbol; use option '-m epsilon' to get it actually printed.
  4896 Moreover, the mathematically important symbolic identifier \<epsilon>
  4897 becomes available as variable, constant etc.  INCOMPATIBILITY,
  4898 
  4899 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  4900 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  4901 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  4902 support corresponding Isar calculations.
  4903 
  4904 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  4905 instead of ":".
  4906 
  4907 * theory SetInterval: changed the syntax for open intervals:
  4908 
  4909   Old       New
  4910   {..n(}    {..<n}
  4911   {)n..}    {n<..}
  4912   {m..n(}   {m..<n}
  4913   {)m..n}   {m<..n}
  4914   {)m..n(}  {m<..<n}
  4915 
  4916 The old syntax is still supported but will disappear in the next
  4917 release.  For conversion use the following Emacs search and replace
  4918 patterns (these are not perfect but work quite well):
  4919 
  4920   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  4921   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  4922 
  4923 * Theory Commutative_Ring (in Library): method comm_ring for proving
  4924 equalities in commutative rings; method 'algebra' provides a generic
  4925 interface.
  4926 
  4927 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  4928 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  4929 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  4930 be a tuple pattern.
  4931 
  4932 Some new syntax forms are available:
  4933 
  4934   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  4935   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  4936   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  4937   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  4938 
  4939 The latter form "\<Sum>x < k. e" used to be based on a separate
  4940 function "Summation", which has been discontinued.
  4941 
  4942 * theory Finite_Set: in structured induction proofs, the insert case
  4943 is now 'case (insert x F)' instead of the old counterintuitive 'case
  4944 (insert F x)'.
  4945 
  4946 * The 'refute' command has been extended to support a much larger
  4947 fragment of HOL, including axiomatic type classes, constdefs and
  4948 typedefs, inductive datatypes and recursion.
  4949 
  4950 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  4951 Requires zChaff with proof generation to be installed.  See
  4952 HOL/ex/SAT_Examples.thy for examples.
  4953 
  4954 * Datatype induction via method 'induct' now preserves the name of the
  4955 induction variable. For example, when proving P(xs::'a list) by
  4956 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  4957 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  4958 in unstructured proof scripts.
  4959 
  4960 * Reworked implementation of records.  Improved scalability for
  4961 records with many fields, avoiding performance problems for type
  4962 inference. Records are no longer composed of nested field types, but
  4963 of nested extension types. Therefore the record type only grows linear
  4964 in the number of extensions and not in the number of fields.  The
  4965 top-level (users) view on records is preserved.  Potential
  4966 INCOMPATIBILITY only in strange cases, where the theory depends on the
  4967 old record representation. The type generated for a record is called
  4968 <record_name>_ext_type.
  4969 
  4970 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  4971 proofs triggered by a record definition or a simproc (if
  4972 quick_and_dirty is enabled).  Definitions of large records can take
  4973 quite long.
  4974 
  4975 New simproc record_upd_simproc for simplification of multiple record
  4976 updates enabled by default.  Moreover, trivial updates are also
  4977 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  4978 occasionally, since simplification is more powerful by default.
  4979 
  4980 * typedef: proper support for polymorphic sets, which contain extra
  4981 type-variables in the term.
  4982 
  4983 * Simplifier: automatically reasons about transitivity chains
  4984 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  4985 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  4986 old proofs break occasionally as simplification may now solve more
  4987 goals than previously.
  4988 
  4989 * Simplifier: converts x <= y into x = y if assumption y <= x is
  4990 present.  Works for all partial orders (class "order"), in particular
  4991 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  4992 just like y <= x.
  4993 
  4994 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  4995 bound variable or a constant then the let is unfolded.  Otherwise
  4996 first a is simplified to b, and then f b is simplified to g. If
  4997 possible we abstract b from g arriving at "let x = b in h x",
  4998 otherwise we unfold the let and arrive at g.  The simproc can be
  4999 enabled/disabled by the reference use_let_simproc.  Potential
  5000 INCOMPATIBILITY since simplification is more powerful by default.
  5001 
  5002 * Classical reasoning: the meson method now accepts theorems as arguments.
  5003 
  5004 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  5005 jobs to provide advice on the provability of subgoals.
  5006 
  5007 * Theory OrderedGroup and Ring_and_Field: various additions and
  5008 improvements to faciliate calculations involving equalities and
  5009 inequalities.
  5010 
  5011 The following theorems have been eliminated or modified
  5012 (INCOMPATIBILITY):
  5013 
  5014   abs_eq             now named abs_of_nonneg
  5015   abs_of_ge_0        now named abs_of_nonneg
  5016   abs_minus_eq       now named abs_of_nonpos
  5017   imp_abs_id         now named abs_of_nonneg
  5018   imp_abs_neg_id     now named abs_of_nonpos
  5019   mult_pos           now named mult_pos_pos
  5020   mult_pos_le        now named mult_nonneg_nonneg
  5021   mult_pos_neg_le    now named mult_nonneg_nonpos
  5022   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  5023   mult_neg           now named mult_neg_neg
  5024   mult_neg_le        now named mult_nonpos_nonpos
  5025 
  5026 * The following lemmas in Ring_and_Field have been added to the simplifier:
  5027      
  5028      zero_le_square
  5029      not_square_less_zero 
  5030 
  5031   The following lemmas have been deleted from Real/RealPow:
  5032   
  5033      realpow_zero_zero
  5034      realpow_two
  5035      realpow_less
  5036      zero_le_power
  5037      realpow_two_le
  5038      abs_realpow_two
  5039      realpow_two_abs     
  5040 
  5041 * Theory Parity: added rules for simplifying exponents.
  5042 
  5043 * Theory List:
  5044 
  5045 The following theorems have been eliminated or modified
  5046 (INCOMPATIBILITY):
  5047 
  5048   list_all_Nil       now named list_all.simps(1)
  5049   list_all_Cons      now named list_all.simps(2)
  5050   list_all_conv      now named list_all_iff
  5051   set_mem_eq         now named mem_iff
  5052 
  5053 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  5054 asymptotic "big O" calculations.  See the notes in BigO.thy.
  5055 
  5056 
  5057 *** HOL-Complex ***
  5058 
  5059 * Theory RealDef: better support for embedding natural numbers and
  5060 integers in the reals.
  5061 
  5062 The following theorems have been eliminated or modified
  5063 (INCOMPATIBILITY):
  5064 
  5065   exp_ge_add_one_self  now requires no hypotheses
  5066   real_of_int_add      reversed direction of equality (use [symmetric])
  5067   real_of_int_minus    reversed direction of equality (use [symmetric])
  5068   real_of_int_diff     reversed direction of equality (use [symmetric])
  5069   real_of_int_mult     reversed direction of equality (use [symmetric])
  5070 
  5071 * Theory RComplete: expanded support for floor and ceiling functions.
  5072 
  5073 * Theory Ln is new, with properties of the natural logarithm
  5074 
  5075 * Hyperreal: There is a new type constructor "star" for making
  5076 nonstandard types.  The old type names are now type synonyms:
  5077 
  5078   hypreal = real star
  5079   hypnat = nat star
  5080   hcomplex = complex star
  5081 
  5082 * Hyperreal: Many groups of similarly-defined constants have been
  5083 replaced by polymorphic versions (INCOMPATIBILITY):
  5084 
  5085   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  5086 
  5087   starset      <-- starsetNat, starsetC
  5088   *s*          <-- *sNat*, *sc*
  5089   starset_n    <-- starsetNat_n, starsetC_n
  5090   *sn*         <-- *sNatn*, *scn*
  5091   InternalSets <-- InternalNatSets, InternalCSets
  5092 
  5093   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  5094   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  5095   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  5096   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  5097   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  5098 
  5099 * Hyperreal: Many type-specific theorems have been removed in favor of
  5100 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  5101 
  5102   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  5103   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  5104   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  5105   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  5106   right_minus <-- hypreal_add_minus
  5107   left_minus <-- {hypreal,hcomplex}_add_minus_left
  5108   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  5109   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  5110   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  5111   mult_1_right <-- hcomplex_mult_one_right
  5112   mult_zero_left <-- hcomplex_mult_zero_left
  5113   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  5114   right_distrib <-- hypnat_add_mult_distrib2
  5115   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  5116   right_inverse <-- hypreal_mult_inverse
  5117   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  5118   order_refl <-- {hypreal,hypnat}_le_refl
  5119   order_trans <-- {hypreal,hypnat}_le_trans
  5120   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  5121   order_less_le <-- {hypreal,hypnat}_less_le
  5122   linorder_linear <-- {hypreal,hypnat}_le_linear
  5123   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  5124   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  5125   add_nonneg_nonneg <-- hypreal_le_add_order
  5126 
  5127 * Hyperreal: Separate theorems having to do with type-specific
  5128 versions of constants have been merged into theorems that apply to the
  5129 new polymorphic constants (INCOMPATIBILITY):
  5130 
  5131   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  5132   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  5133   STAR_Un <-- {STAR,NatStar,STARC}_Un
  5134   STAR_Int <-- {STAR,NatStar,STARC}_Int
  5135   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  5136   STAR_subset <-- {STAR,NatStar,STARC}_subset
  5137   STAR_mem <-- {STAR,NatStar,STARC}_mem
  5138   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  5139   STAR_diff <-- {STAR,STARC}_diff
  5140   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  5141     STARC_hcomplex_of_complex}_image_subset
  5142   starset_n_Un <-- starset{Nat,C}_n_Un
  5143   starset_n_Int <-- starset{Nat,C}_n_Int
  5144   starset_n_Compl <-- starset{Nat,C}_n_Compl
  5145   starset_n_diff <-- starset{Nat,C}_n_diff
  5146   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  5147   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  5148   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  5149   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  5150   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  5151   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  5152   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  5153   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  5154   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  5155   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  5156   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  5157   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  5158   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  5159   starfun_diff <-- starfun{C,RC,CR}_diff
  5160   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  5161   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  5162   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  5163   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  5164   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  5165   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  5166   starfun_Id <-- starfunC_Id
  5167   starfun_approx <-- starfun{Nat,CR}_approx
  5168   starfun_capprox <-- starfun{C,RC}_capprox
  5169   starfun_abs <-- starfunNat_rabs
  5170   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  5171   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  5172   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  5173   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  5174   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  5175   starfun_add_approx <-- starfunCR_add_approx
  5176   starfun_inverse_inverse <-- starfunC_inverse_inverse
  5177   starfun_divide <-- starfun{C,CR,RC}_divide
  5178   starfun_n <-- starfun{Nat,C}_n
  5179   starfun_n_mult <-- starfun{Nat,C}_n_mult
  5180   starfun_n_add <-- starfun{Nat,C}_n_add
  5181   starfun_n_add_minus <-- starfunNat_n_add_minus
  5182   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  5183   starfun_n_minus <-- starfun{Nat,C}_n_minus
  5184   starfun_n_eq <-- starfun{Nat,C}_n_eq
  5185 
  5186   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  5187   star_n_minus <-- {hypreal,hcomplex}_minus
  5188   star_n_diff <-- {hypreal,hcomplex}_diff
  5189   star_n_mult <-- {hypreal,hcomplex}_mult
  5190   star_n_inverse <-- {hypreal,hcomplex}_inverse
  5191   star_n_le <-- {hypreal,hypnat}_le
  5192   star_n_less <-- {hypreal,hypnat}_less
  5193   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  5194   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  5195   star_n_abs <-- hypreal_hrabs
  5196   star_n_divide <-- hcomplex_divide
  5197 
  5198   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  5199   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  5200   star_of_diff <-- hypreal_of_real_diff
  5201   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  5202   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  5203   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  5204   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  5205   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  5206   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  5207   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  5208   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  5209   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  5210   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  5211   star_of_number_of <-- {hypreal,hcomplex}_number_of
  5212   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  5213   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  5214   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  5215   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  5216   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  5217   star_of_power <-- hypreal_of_real_power
  5218   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  5219 
  5220 * Hyperreal: new method "transfer" that implements the transfer
  5221 principle of nonstandard analysis. With a subgoal that mentions
  5222 nonstandard types like "'a star", the command "apply transfer"
  5223 replaces it with an equivalent one that mentions only standard types.
  5224 To be successful, all free variables must have standard types; non-
  5225 standard variables must have explicit universal quantifiers.
  5226 
  5227 * Hyperreal: A theory of Taylor series.
  5228 
  5229 
  5230 *** HOLCF ***
  5231 
  5232 * Discontinued special version of 'constdefs' (which used to support
  5233 continuous functions) in favor of the general Pure one with full
  5234 type-inference.
  5235 
  5236 * New simplification procedure for solving continuity conditions; it
  5237 is much faster on terms with many nested lambda abstractions (cubic
  5238 instead of exponential time).
  5239 
  5240 * New syntax for domain package: selector names are now optional.
  5241 Parentheses should be omitted unless argument is lazy, for example:
  5242 
  5243   domain 'a stream = cons "'a" (lazy "'a stream")
  5244 
  5245 * New command 'fixrec' for defining recursive functions with pattern
  5246 matching; defining multiple functions with mutual recursion is also
  5247 supported.  Patterns may include the constants cpair, spair, up, sinl,
  5248 sinr, or any data constructor defined by the domain package. The given
  5249 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  5250 syntax and examples.
  5251 
  5252 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  5253 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  5254 but the proof obligation additionally includes an admissibility
  5255 requirement. The packages generate instances of class cpo or pcpo,
  5256 with continuity and strictness theorems for Rep and Abs.
  5257 
  5258 * HOLCF: Many theorems have been renamed according to a more standard naming
  5259 scheme (INCOMPATIBILITY):
  5260 
  5261   foo_inject:  "foo$x = foo$y ==> x = y"
  5262   foo_eq:      "(foo$x = foo$y) = (x = y)"
  5263   foo_less:    "(foo$x << foo$y) = (x << y)"
  5264   foo_strict:  "foo$UU = UU"
  5265   foo_defined: "... ==> foo$x ~= UU"
  5266   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  5267 
  5268 
  5269 *** ZF ***
  5270 
  5271 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  5272 including the First Isomorphism Theorem (on quotienting by the kernel
  5273 of a homomorphism).
  5274 
  5275 * ZF/Simplifier: install second copy of type solver that actually
  5276 makes use of TC rules declared to Isar proof contexts (or locales);
  5277 the old version is still required for ML proof scripts.
  5278 
  5279 
  5280 *** Cube ***
  5281 
  5282 * Converted to Isar theory format; use locales instead of axiomatic
  5283 theories.
  5284 
  5285 
  5286 *** ML ***
  5287 
  5288 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  5289 for ||>, ||>>, |>>,
  5290 
  5291 * Pure/library.ML no longer defines its own option datatype, but uses
  5292 that of the SML basis, which has constructors NONE and SOME instead of
  5293 None and Some, as well as exception Option.Option instead of OPTION.
  5294 The functions the, if_none, is_some, is_none have been adapted
  5295 accordingly, while Option.map replaces apsome.
  5296 
  5297 * Pure/library.ML: the exception LIST has been given up in favour of
  5298 the standard exceptions Empty and Subscript, as well as
  5299 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  5300 superceded by the standard hd and tl functions etc.
  5301 
  5302 A number of basic list functions are no longer exported to the ML
  5303 toplevel, as they are variants of predefined functions.  The following
  5304 suggests how one can translate existing code:
  5305 
  5306     rev_append xs ys = List.revAppend (xs, ys)
  5307     nth_elem (i, xs) = List.nth (xs, i)
  5308     last_elem xs = List.last xs
  5309     flat xss = List.concat xss
  5310     seq fs = List.app fs
  5311     partition P xs = List.partition P xs
  5312     mapfilter f xs = List.mapPartial f xs
  5313 
  5314 * Pure/library.ML: several combinators for linear functional
  5315 transformations, notably reverse application and composition:
  5316 
  5317   x |> f                f #> g
  5318   (x, y) |-> f          f #-> g
  5319 
  5320 * Pure/library.ML: introduced/changed precedence of infix operators:
  5321 
  5322   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  5323   infix 2 ?;
  5324   infix 3 o oo ooo oooo;
  5325   infix 4 ~~ upto downto;
  5326 
  5327 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  5328 infix operators.
  5329 
  5330 * Pure/library.ML: natural list combinators fold, fold_rev, and
  5331 fold_map support linear functional transformations and nesting.  For
  5332 example:
  5333 
  5334   fold f [x1, ..., xN] y =
  5335     y |> f x1 |> ... |> f xN
  5336 
  5337   (fold o fold) f [xs1, ..., xsN] y =
  5338     y |> fold f xs1 |> ... |> fold f xsN
  5339 
  5340   fold f [x1, ..., xN] =
  5341     f x1 #> ... #> f xN
  5342 
  5343   (fold o fold) f [xs1, ..., xsN] =
  5344     fold f xs1 #> ... #> fold f xsN
  5345 
  5346 * Pure/library.ML: the following selectors on type 'a option are
  5347 available:
  5348 
  5349   the:               'a option -> 'a  (*partial*)
  5350   these:             'a option -> 'a  where 'a = 'b list
  5351   the_default: 'a -> 'a option -> 'a
  5352   the_list:          'a option -> 'a list
  5353 
  5354 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5355 basic operations for association lists, following natural argument
  5356 order; moreover the explicit equality predicate passed here avoids
  5357 potentially expensive polymorphic runtime equality checks.
  5358 The old functions may be expressed as follows:
  5359 
  5360   assoc = uncurry (AList.lookup (op =))
  5361   assocs = these oo AList.lookup (op =)
  5362   overwrite = uncurry (AList.update (op =)) o swap
  5363 
  5364 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5365 
  5366   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  5367   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  5368 
  5369 replacing make_keylist and keyfilter (occassionally used)
  5370 Naive rewrites:
  5371 
  5372   make_keylist = AList.make
  5373   keyfilter = AList.find (op =)
  5374 
  5375 * eq_fst and eq_snd now take explicit equality parameter, thus
  5376   avoiding eqtypes. Naive rewrites:
  5377 
  5378     eq_fst = eq_fst (op =)
  5379     eq_snd = eq_snd (op =)
  5380 
  5381 * Removed deprecated apl and apr (rarely used).
  5382   Naive rewrites:
  5383 
  5384     apl (n, op) =>>= curry op n
  5385     apr (op, m) =>>= fn n => op (n, m)
  5386 
  5387 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  5388 provides a reasonably efficient light-weight implementation of sets as
  5389 lists.
  5390 
  5391 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  5392 few new operations; existing lookup and update are now curried to
  5393 follow natural argument order (for use with fold etc.);
  5394 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  5395 
  5396 * Pure/General: output via the Isabelle channels of
  5397 writeln/warning/error etc. is now passed through Output.output, with a
  5398 hook for arbitrary transformations depending on the print_mode
  5399 (cf. Output.add_mode -- the first active mode that provides a output
  5400 function wins).  Already formatted output may be embedded into further
  5401 text via Output.raw; the result of Pretty.string_of/str_of and derived
  5402 functions (string_of_term/cterm/thm etc.) is already marked raw to
  5403 accommodate easy composition of diagnostic messages etc.  Programmers
  5404 rarely need to care about Output.output or Output.raw at all, with
  5405 some notable exceptions: Output.output is required when bypassing the
  5406 standard channels (writeln etc.), or in token translations to produce
  5407 properly formatted results; Output.raw is required when capturing
  5408 already output material that will eventually be presented to the user
  5409 a second time.  For the default print mode, both Output.output and
  5410 Output.raw have no effect.
  5411 
  5412 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  5413 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  5414 cumulative results are displayed at the end of a batch session.
  5415 
  5416 * Pure/General: File.sysify_path and File.quote_sysify path have been
  5417 replaced by File.platform_path and File.shell_path (with appropriate
  5418 hooks).  This provides a clean interface for unusual systems where the
  5419 internal and external process view of file names are different.
  5420 
  5421 * Pure: more efficient orders for basic syntactic entities: added
  5422 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  5423 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  5424 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  5425 orders now -- potential INCOMPATIBILITY for code that depends on a
  5426 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  5427 Library.sort_strings on result).
  5428 
  5429 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  5430 fold_types traverse types/terms from left to right, observing natural
  5431 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  5432 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  5433 
  5434 * Pure: name spaces have been refined, with significant changes of the
  5435 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  5436 to extern(_table).  The plain name entry path is superceded by a
  5437 general 'naming' context, which also includes the 'policy' to produce
  5438 a fully qualified name and external accesses of a fully qualified
  5439 name; NameSpace.extend is superceded by context dependent
  5440 Sign.declare_name.  Several theory and proof context operations modify
  5441 the naming context.  Especially note Theory.restore_naming and
  5442 ProofContext.restore_naming to get back to a sane state; note that
  5443 Theory.add_path is no longer sufficient to recover from
  5444 Theory.absolute_path in particular.
  5445 
  5446 * Pure: new flags short_names (default false) and unique_names
  5447 (default true) for controlling output of qualified names.  If
  5448 short_names is set, names are printed unqualified.  If unique_names is
  5449 reset, the name prefix is reduced to the minimum required to achieve
  5450 the original result when interning again, even if there is an overlap
  5451 with earlier declarations.
  5452 
  5453 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  5454 now 'extend', and 'merge' gets an additional Pretty.pp argument
  5455 (useful for printing error messages).  INCOMPATIBILITY.
  5456 
  5457 * Pure: major reorganization of the theory context.  Type Sign.sg and
  5458 Theory.theory are now identified, referring to the universal
  5459 Context.theory (see Pure/context.ML).  Actual signature and theory
  5460 content is managed as theory data.  The old code and interfaces were
  5461 spread over many files and structures; the new arrangement introduces
  5462 considerable INCOMPATIBILITY to gain more clarity:
  5463 
  5464   Context -- theory management operations (name, identity, inclusion,
  5465     parents, ancestors, merge, etc.), plus generic theory data;
  5466 
  5467   Sign -- logical signature and syntax operations (declaring consts,
  5468     types, etc.), plus certify/read for common entities;
  5469 
  5470   Theory -- logical theory operations (stating axioms, definitions,
  5471     oracles), plus a copy of logical signature operations (consts,
  5472     types, etc.); also a few basic management operations (Theory.copy,
  5473     Theory.merge, etc.)
  5474 
  5475 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  5476 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  5477 for convenience -- they merely return the theory.
  5478 
  5479 * Pure: type Type.tsig is superceded by theory in most interfaces.
  5480 
  5481 * Pure: the Isar proof context type is already defined early in Pure
  5482 as Context.proof (note that ProofContext.context and Proof.context are
  5483 aliases, where the latter is the preferred name).  This enables other
  5484 Isabelle components to refer to that type even before Isar is present.
  5485 
  5486 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  5487 typeK, constK, axiomK, oracleK), but provide explicit operations for
  5488 any of these kinds.  For example, Sign.intern typeK is now
  5489 Sign.intern_type, Theory.hide_space Sign.typeK is now
  5490 Theory.hide_types.  Also note that former
  5491 Theory.hide_classes/types/consts are now
  5492 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  5493 internalize their arguments!  INCOMPATIBILITY.
  5494 
  5495 * Pure: get_thm interface (of PureThy and ProofContext) expects
  5496 datatype thmref (with constructors Name and NameSelection) instead of
  5497 plain string -- INCOMPATIBILITY;
  5498 
  5499 * Pure: cases produced by proof methods specify options, where NONE
  5500 means to remove case bindings -- INCOMPATIBILITY in
  5501 (RAW_)METHOD_CASES.
  5502 
  5503 * Pure: the following operations retrieve axioms or theorems from a
  5504 theory node or theory hierarchy, respectively:
  5505 
  5506   Theory.axioms_of: theory -> (string * term) list
  5507   Theory.all_axioms_of: theory -> (string * term) list
  5508   PureThy.thms_of: theory -> (string * thm) list
  5509   PureThy.all_thms_of: theory -> (string * thm) list
  5510 
  5511 * Pure: print_tac now outputs the goal through the trace channel.
  5512 
  5513 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  5514 Reference Toplevel.debug (default false) controls detailed printing
  5515 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  5516 controls execution profiling -- set to 1 for time and 2 for space
  5517 (both increase the runtime).
  5518 
  5519 * Isar session: The initial use of ROOT.ML is now always timed,
  5520 i.e. the log will show the actual process times, in contrast to the
  5521 elapsed wall-clock time that the outer shell wrapper produces.
  5522 
  5523 * Simplifier: improved handling of bound variables (nameless
  5524 representation, avoid allocating new strings).  Simprocs that invoke
  5525 the Simplifier recursively should use Simplifier.inherit_bounds to
  5526 avoid local name clashes.  Failure to do so produces warnings
  5527 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  5528 for further details.
  5529 
  5530 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  5531 bindings for all theorems stored within a given theory; this may help
  5532 in porting non-Isar theories to Isar ones, while keeping ML proof
  5533 scripts for the time being.
  5534 
  5535 * ML operator HTML.with_charset specifies the charset begin used for
  5536 generated HTML files.  For example:
  5537 
  5538   HTML.with_charset "utf-8" use_thy "Hebrew";
  5539   HTML.with_charset "utf-8" use_thy "Chinese";
  5540 
  5541 
  5542 *** System ***
  5543 
  5544 * Allow symlinks to all proper Isabelle executables (Isabelle,
  5545 isabelle, isatool etc.).
  5546 
  5547 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  5548 isatool doc, isatool mkdir, display_drafts etc.).
  5549 
  5550 * isatool usedir: option -f allows specification of the ML file to be
  5551 used by Isabelle; default is ROOT.ML.
  5552 
  5553 * New isatool version outputs the version identifier of the Isabelle
  5554 distribution being used.
  5555 
  5556 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  5557 (containing Boolean satisfiability problems) into Isabelle/HOL
  5558 theories.
  5559 
  5560 
  5561 
  5562 New in Isabelle2004 (April 2004)
  5563 --------------------------------
  5564 
  5565 *** General ***
  5566 
  5567 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  5568   Replaces linorder.ML.
  5569 
  5570 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  5571   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  5572   (\<a>...\<z>), are now considered normal letters, and can therefore
  5573   be used anywhere where an ASCII letter (a...zA...Z) has until
  5574   now. COMPATIBILITY: This obviously changes the parsing of some
  5575   terms, especially where a symbol has been used as a binder, say
  5576   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  5577   as an identifier.  Fix it by inserting a space around former
  5578   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  5579   existing theory and ML files.
  5580 
  5581 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  5582 
  5583 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  5584   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  5585   a normal (but invisible) letter. For multiple letter subscripts repeat
  5586   \<^isub> like this: x\<^isub>1\<^isub>2.
  5587 
  5588 * Pure: There are now sub-/superscripts that can span more than one
  5589   character. Text between \<^bsub> and \<^esub> is set in subscript in
  5590   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  5591   superscript. The new control characters are not identifier parts.
  5592 
  5593 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5594   content of "..." to the latex file instead of \isacntrl... . The "..."
  5595   may consist of any printable characters excluding the end bracket >.
  5596 
  5597 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5598   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5599   declare constants "final", which prevents their being given a definition
  5600   later.  It is useful for constants whose behaviour is fixed axiomatically
  5601   rather than definitionally, such as the meta-logic connectives.
  5602 
  5603 * Pure: 'instance' now handles general arities with general sorts
  5604   (i.e. intersections of classes),
  5605 
  5606 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5607   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5608   It can be changed to alter the colors/layout of generated pages.
  5609 
  5610 
  5611 *** Isar ***
  5612 
  5613 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5614   cut_tac, subgoal_tac and thin_tac:
  5615   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5616     locales are no longer forced to write Isar proof scripts.
  5617     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5618     emulations.
  5619   - INCOMPATIBILITY: names of variables to be instantiated may no
  5620     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5621     This is consistent with the instantiation attribute "where".
  5622 
  5623 * Attributes "where" and "of":
  5624   - Now take type variables of instantiated theorem into account when reading
  5625     the instantiation string.  This fixes a bug that caused instantiated
  5626     theorems to have too special types in some circumstances.
  5627   - "where" permits explicit instantiations of type variables.
  5628 
  5629 * Calculation commands "moreover" and "also" no longer interfere with
  5630   current facts ("this"), admitting arbitrary combinations with "then"
  5631   and derived forms.
  5632 
  5633 * Locales:
  5634   - Goal statements involving the context element "includes" no longer
  5635     generate theorems with internal delta predicates (those ending on
  5636     "_axioms") in the premise.
  5637     Resolve particular premise with <locale>.intro to obtain old form.
  5638   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5639     specification and "includes" elements in goal statement.
  5640   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5641     [intro?] and [elim?] (respectively) by default.
  5642   - Experimental command for instantiation of locales in proof contexts:
  5643         instantiate <label>[<attrs>]: <loc>
  5644     Instantiates locale <loc> and adds all its theorems to the current context
  5645     taking into account their attributes.  Label and attrs are optional
  5646     modifiers, like in theorem declarations.  If present, names of
  5647     instantiated theorems are qualified with <label>, and the attributes
  5648     <attrs> are applied after any attributes these theorems might have already.
  5649       If the locale has assumptions, a chained fact of the form
  5650     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5651     are derived.  The command does not support old-style locales declared
  5652     with "locale (open)".
  5653       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5654 
  5655 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5656   (Isar) contexts.
  5657 
  5658 
  5659 *** HOL ***
  5660 
  5661 * Proof import: new image HOL4 contains the imported library from
  5662   the HOL4 system with about 2500 theorems. It is imported by
  5663   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5664   can be used like any other Isabelle image.  See
  5665   HOL/Import/HOL/README for more information.
  5666 
  5667 * Simplifier:
  5668   - Much improved handling of linear and partial orders.
  5669     Reasoners for linear and partial orders are set up for type classes
  5670     "linorder" and "order" respectively, and are added to the default simpset
  5671     as solvers.  This means that the simplifier can build transitivity chains
  5672     to solve goals from the assumptions.
  5673   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5674     of blast or auto after simplification become unnecessary because the goal
  5675     is solved by simplification already.
  5676 
  5677 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5678     all proved in axiomatic type classes for semirings, rings and fields.
  5679 
  5680 * Numerics:
  5681   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5682     now formalized using the Ring_and_Field theory mentioned above.
  5683   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5684     than before, because now they are set up once in a generic manner.
  5685   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5686     Look for the general versions in Ring_and_Field (and Power if they concern
  5687     exponentiation).
  5688 
  5689 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5690 
  5691 * Records:
  5692   - Record types are now by default printed with their type abbreviation
  5693     instead of the list of all field types. This can be configured via
  5694     the reference "print_record_type_abbr".
  5695   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5696     (not enabled by default).
  5697   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5698     EX x. x = sel r to True (not enabled by default).
  5699   - Tactic "record_split_simp_tac" to split and simplify records added.
  5700 
  5701 * 'specification' command added, allowing for definition by
  5702   specification.  There is also an 'ax_specification' command that
  5703   introduces the new constants axiomatically.
  5704 
  5705 * arith(_tac) is now able to generate counterexamples for reals as well.
  5706 
  5707 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5708 
  5709 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5710   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5711 
  5712 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5713   matrix theory to linear programming.
  5714 
  5715 * Unions and Intersections:
  5716   The latex output syntax of UN and INT has been changed
  5717   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5718   i.e. the index formulae has become a subscript.
  5719   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5720 
  5721 * Unions and Intersections over Intervals:
  5722   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5723   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5724   like in normal math, and corresponding versions for < and for intersection.
  5725 
  5726 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5727   lexicographic dictonary ordering has been added as "lexord".
  5728 
  5729 * ML: the legacy theory structures Int and List have been removed. They had
  5730   conflicted with ML Basis Library structures having the same names.
  5731 
  5732 * 'refute' command added to search for (finite) countermodels.  Only works
  5733   for a fragment of HOL.  The installation of an external SAT solver is
  5734   highly recommended.  See "HOL/Refute.thy" for details.
  5735 
  5736 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5737   formulae under an assignment of free variables to random values.
  5738   In contrast to 'refute', it can deal with inductive datatypes,
  5739   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5740   for examples.
  5741 
  5742 
  5743 *** HOLCF ***
  5744 
  5745 * Streams now come with concatenation and are part of the HOLCF image
  5746 
  5747 
  5748 
  5749 New in Isabelle2003 (May 2003)
  5750 ------------------------------
  5751 
  5752 *** General ***
  5753 
  5754 * Provers/simplifier:
  5755 
  5756   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5757     Assumptions are now subject to complete mutual simplification,
  5758     not just from left to right. The simplifier now preserves
  5759     the order of assumptions.
  5760 
  5761     Potential INCOMPATIBILITY:
  5762 
  5763     -- simp sometimes diverges where the old version did
  5764        not, e.g. invoking simp on the goal
  5765 
  5766         [| P (f x); y = x; f x = f y |] ==> Q
  5767 
  5768        now gives rise to the infinite reduction sequence
  5769 
  5770         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5771 
  5772        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5773        kind of problem.
  5774 
  5775     -- Tactics combining classical reasoner and simplification (such as auto)
  5776        are also affected by this change, because many of them rely on
  5777        simp. They may sometimes diverge as well or yield a different numbers
  5778        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5779        in case of problems. Sometimes subsequent calls to the classical
  5780        reasoner will fail because a preceeding call to the simplifier too
  5781        eagerly simplified the goal, e.g. deleted redundant premises.
  5782 
  5783   - The simplifier trace now shows the names of the applied rewrite rules
  5784 
  5785   - You can limit the number of recursive invocations of the simplifier
  5786     during conditional rewriting (where the simplifie tries to solve the
  5787     conditions before applying the rewrite rule):
  5788     ML "simp_depth_limit := n"
  5789     where n is an integer. Thus you can force termination where previously
  5790     the simplifier would diverge.
  5791 
  5792   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5793 
  5794   - No longer aborts on failed congruence proof.  Instead, the
  5795     congruence is ignored.
  5796 
  5797 * Pure: New generic framework for extracting programs from constructive
  5798   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5799   as HOL/Extraction for some case studies.
  5800 
  5801 * Pure: The main goal of the proof state is no longer shown by default, only
  5802 the subgoals. This behaviour is controlled by a new flag.
  5803    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5804 (ML: Proof.show_main_goal).
  5805 
  5806 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5807 rules whose conclusion matches subgoal 1:
  5808       PG menu: Isabelle/Isar -> Show me -> matching rules
  5809 The rules are ordered by how closely they match the subgoal.
  5810 In particular, rules that solve a subgoal outright are displayed first
  5811 (or rather last, the way they are printed).
  5812 (ML: ProofGeneral.print_intros())
  5813 
  5814 * Pure: New flag trace_unify_fail causes unification to print
  5815 diagnostic information (PG: in trace buffer) when it fails. This is
  5816 useful for figuring out why single step proofs like rule, erule or
  5817 assumption failed.
  5818 
  5819 * Pure: Locale specifications now produce predicate definitions
  5820 according to the body of text (covering assumptions modulo local
  5821 definitions); predicate "loc_axioms" covers newly introduced text,
  5822 while "loc" is cumulative wrt. all included locale expressions; the
  5823 latter view is presented only on export into the global theory
  5824 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5825 on the old view without predicates;
  5826 
  5827 * Pure: predefined locales "var" and "struct" are useful for sharing
  5828 parameters (as in CASL, for example); just specify something like
  5829 ``var x + var y + struct M'' as import;
  5830 
  5831 * Pure: improved thms_containing: proper indexing of facts instead of
  5832 raw theorems; check validity of results wrt. current name space;
  5833 include local facts of proof configuration (also covers active
  5834 locales), cover fixed variables in index; may use "_" in term
  5835 specification; an optional limit for the number of printed facts may
  5836 be given (the default is 40);
  5837 
  5838 * Pure: disallow duplicate fact bindings within new-style theory files
  5839 (batch-mode only);
  5840 
  5841 * Provers: improved induct method: assumptions introduced by case
  5842 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5843 the goal statement); "foo" still refers to all facts collectively;
  5844 
  5845 * Provers: the function blast.overloaded has been removed: all constants
  5846 are regarded as potentially overloaded, which improves robustness in exchange
  5847 for slight decrease in efficiency;
  5848 
  5849 * Provers/linorder: New generic prover for transitivity reasoning over
  5850 linear orders.  Note: this prover is not efficient!
  5851 
  5852 * Isar: preview of problems to finish 'show' now produce an error
  5853 rather than just a warning (in interactive mode);
  5854 
  5855 
  5856 *** HOL ***
  5857 
  5858 * arith(_tac)
  5859 
  5860  - Produces a counter example if it cannot prove a goal.
  5861    Note that the counter example may be spurious if the goal is not a formula
  5862    of quantifier-free linear arithmetic.
  5863    In ProofGeneral the counter example appears in the trace buffer.
  5864 
  5865  - Knows about div k and mod k where k is a numeral of type nat or int.
  5866 
  5867  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  5868    linear arithmetic fails. This takes account of quantifiers and divisibility.
  5869    Presburger arithmetic can also be called explicitly via presburger(_tac).
  5870 
  5871 * simp's arithmetic capabilities have been enhanced a bit: it now
  5872 takes ~= in premises into account (by performing a case split);
  5873 
  5874 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  5875 are distributed over a sum of terms;
  5876 
  5877 * New tactic "trans_tac" and method "trans" instantiate
  5878 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  5879 "<=", "<" and "=").
  5880 
  5881 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  5882 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  5883 
  5884 * 'typedef' command has new option "open" to suppress the set
  5885 definition;
  5886 
  5887 * functions Min and Max on finite sets have been introduced (theory
  5888 Finite_Set);
  5889 
  5890 * attribute [symmetric] now works for relations as well; it turns
  5891 (x,y) : R^-1 into (y,x) : R, and vice versa;
  5892 
  5893 * induct over a !!-quantified statement (say !!x1..xn):
  5894   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  5895 
  5896 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  5897 %x. None. Warning: empty_def now refers to the previously hidden definition
  5898 of the empty set.
  5899 
  5900 * Algebra: formalization of classical algebra.  Intended as base for
  5901 any algebraic development in Isabelle.  Currently covers group theory
  5902 (up to Sylow's theorem) and ring theory (Universal Property of
  5903 Univariate Polynomials).  Contributions welcome;
  5904 
  5905 * GroupTheory: deleted, since its material has been moved to Algebra;
  5906 
  5907 * Complex: new directory of the complex numbers with numeric constants,
  5908 nonstandard complex numbers, and some complex analysis, standard and
  5909 nonstandard (Jacques Fleuriot);
  5910 
  5911 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  5912 
  5913 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  5914 Fleuriot);
  5915 
  5916 * Real/HahnBanach: updated and adapted to locales;
  5917 
  5918 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  5919 Gray and Kramer);
  5920 
  5921 * UNITY: added the Meier-Sanders theory of progress sets;
  5922 
  5923 * MicroJava: bytecode verifier and lightweight bytecode verifier
  5924 as abstract algorithms, instantiated to the JVM;
  5925 
  5926 * Bali: Java source language formalization. Type system, operational
  5927 semantics, axiomatic semantics. Supported language features:
  5928 classes, interfaces, objects,virtual methods, static methods,
  5929 static/instance fields, arrays, access modifiers, definite
  5930 assignment, exceptions.
  5931 
  5932 
  5933 *** ZF ***
  5934 
  5935 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  5936 universe, etc.);
  5937 
  5938 * Main ZF: virtually all theories converted to new-style format;
  5939 
  5940 
  5941 *** ML ***
  5942 
  5943 * Pure: Tactic.prove provides sane interface for internal proofs;
  5944 omits the infamous "standard" operation, so this is more appropriate
  5945 than prove_goalw_cterm in many situations (e.g. in simprocs);
  5946 
  5947 * Pure: improved error reporting of simprocs;
  5948 
  5949 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  5950 up simprocs;
  5951 
  5952 
  5953 *** Document preparation ***
  5954 
  5955 * uses \par instead of \\ for line breaks in theory text. This may
  5956 shift some page breaks in large documents. To get the old behaviour
  5957 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  5958 
  5959 * minimized dependencies of isabelle.sty and isabellesym.sty on
  5960 other packages
  5961 
  5962 * \<euro> now needs package babel/greek instead of marvosym (which
  5963 broke \Rightarrow)
  5964 
  5965 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  5966 textcomp package)
  5967 
  5968 
  5969 
  5970 New in Isabelle2002 (March 2002)
  5971 --------------------------------
  5972 
  5973 *** Document preparation ***
  5974 
  5975 * greatly simplified document preparation setup, including more
  5976 graceful interpretation of isatool usedir -i/-d/-D options, and more
  5977 instructive isatool mkdir; users should basically be able to get
  5978 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  5979 users may run a separate document processing stage manually like this:
  5980 "isatool usedir -D output HOL Test && isatool document Test/output";
  5981 
  5982 * theory dependency graph may now be incorporated into documents;
  5983 isatool usedir -g true will produce session_graph.eps/.pdf for use
  5984 with \includegraphics of LaTeX;
  5985 
  5986 * proper spacing of consecutive markup elements, especially text
  5987 blocks after section headings;
  5988 
  5989 * support bold style (for single symbols only), input syntax is like
  5990 this: "\<^bold>\<alpha>" or "\<^bold>A";
  5991 
  5992 * \<bullet> is now output as bold \cdot by default, which looks much
  5993 better in printed text;
  5994 
  5995 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  5996 note that these symbols are currently unavailable in Proof General /
  5997 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  5998 
  5999 * isatool latex no longer depends on changed TEXINPUTS, instead
  6000 isatool document copies the Isabelle style files to the target
  6001 location;
  6002 
  6003 
  6004 *** Isar ***
  6005 
  6006 * Pure/Provers: improved proof by cases and induction;
  6007   - 'case' command admits impromptu naming of parameters (such as
  6008     "case (Suc n)");
  6009   - 'induct' method divinates rule instantiation from the inductive
  6010     claim; no longer requires excessive ?P bindings for proper
  6011     instantiation of cases;
  6012   - 'induct' method properly enumerates all possibilities of set/type
  6013     rules; as a consequence facts may be also passed through *type*
  6014     rules without further ado;
  6015   - 'induct' method now derives symbolic cases from the *rulified*
  6016     rule (before it used to rulify cases stemming from the internal
  6017     atomized version); this means that the context of a non-atomic
  6018     statement becomes is included in the hypothesis, avoiding the
  6019     slightly cumbersome show "PROP ?case" form;
  6020   - 'induct' may now use elim-style induction rules without chaining
  6021     facts, using ``missing'' premises from the goal state; this allows
  6022     rules stemming from inductive sets to be applied in unstructured
  6023     scripts, while still benefitting from proper handling of non-atomic
  6024     statements; NB: major inductive premises need to be put first, all
  6025     the rest of the goal is passed through the induction;
  6026   - 'induct' proper support for mutual induction involving non-atomic
  6027     rule statements (uses the new concept of simultaneous goals, see
  6028     below);
  6029   - append all possible rule selections, but only use the first
  6030     success (no backtracking);
  6031   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  6032   - undeclared rule case names default to numbers 1, 2, 3, ...;
  6033   - added 'print_induct_rules' (covered by help item in recent Proof
  6034     General versions);
  6035   - moved induct/cases attributes to Pure, methods to Provers;
  6036   - generic method setup instantiated for FOL and HOL;
  6037 
  6038 * Pure: support multiple simultaneous goal statements, for example
  6039 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  6040 meta-level mechanism, this acts as if several individual goals had
  6041 been stated separately; in particular common proof methods need to be
  6042 repeated in order to cover all claims; note that a single elimination
  6043 step is *not* sufficient to establish the two conjunctions, so this
  6044 fails:
  6045 
  6046   assume "A & B" then have A and B ..   (*".." fails*)
  6047 
  6048 better use "obtain" in situations as above; alternative refer to
  6049 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  6050 
  6051 * Pure: proper integration with ``locales''; unlike the original
  6052 version by Florian Kammller, Isar locales package high-level proof
  6053 contexts rather than raw logical ones (e.g. we admit to include
  6054 attributes everywhere); operations on locales include merge and
  6055 rename; support for implicit arguments (``structures''); simultaneous
  6056 type-inference over imports and text; see also HOL/ex/Locales.thy for
  6057 some examples;
  6058 
  6059 * Pure: the following commands have been ``localized'', supporting a
  6060 target locale specification "(in name)": 'lemma', 'theorem',
  6061 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  6062 stored both within the locale and at the theory level (exported and
  6063 qualified by the locale name);
  6064 
  6065 * Pure: theory goals may now be specified in ``long'' form, with
  6066 ad-hoc contexts consisting of arbitrary locale elements. for example
  6067 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  6068 definitions may be given, too); the result is a meta-level rule with
  6069 the context elements being discharged in the obvious way;
  6070 
  6071 * Pure: new proof command 'using' allows to augment currently used
  6072 facts after a goal statement ('using' is syntactically analogous to
  6073 'apply', but acts on the goal's facts only); this allows chained facts
  6074 to be separated into parts given before and after a claim, as in
  6075 ``from a and b have C using d and e <proof>'';
  6076 
  6077 * Pure: renamed "antecedent" case to "rule_context";
  6078 
  6079 * Pure: new 'judgment' command records explicit information about the
  6080 object-logic embedding (used by several tools internally); no longer
  6081 use hard-wired "Trueprop";
  6082 
  6083 * Pure: added 'corollary' command;
  6084 
  6085 * Pure: fixed 'token_translation' command;
  6086 
  6087 * Pure: removed obsolete 'exported' attribute;
  6088 
  6089 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  6090 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  6091 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  6092 
  6093 * Pure: method 'atomize' presents local goal premises as object-level
  6094 statements (atomic meta-level propositions); setup controlled via
  6095 rewrite rules declarations of 'atomize' attribute; example
  6096 application: 'induct' method with proper rule statements in improper
  6097 proof *scripts*;
  6098 
  6099 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  6100 now consider the syntactic context of assumptions, giving a better
  6101 chance to get type-inference of the arguments right (this is
  6102 especially important for locales);
  6103 
  6104 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  6105 mode;
  6106 
  6107 * Pure/obtain: the formal conclusion "thesis", being marked as
  6108 ``internal'', may no longer be reference directly in the text;
  6109 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  6110 situations;
  6111 
  6112 * Pure: generic 'sym' attribute which declares a rule both as pure
  6113 'elim?' and for the 'symmetric' operation;
  6114 
  6115 * Pure: marginal comments ``--'' may now occur just anywhere in the
  6116 text; the fixed correlation with particular command syntax has been
  6117 discontinued;
  6118 
  6119 * Pure: new method 'rules' is particularly well-suited for proof
  6120 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  6121 but often produces more compact proof terms with less detours;
  6122 
  6123 * Pure/Provers/classical: simplified integration with pure rule
  6124 attributes and methods; the classical "intro?/elim?/dest?"
  6125 declarations coincide with the pure ones; the "rule" method no longer
  6126 includes classically swapped intros; "intro" and "elim" methods no
  6127 longer pick rules from the context; also got rid of ML declarations
  6128 AddXIs/AddXEs/AddXDs; all of this has some potential for
  6129 INCOMPATIBILITY;
  6130 
  6131 * Provers/classical: attribute 'swapped' produces classical inversions
  6132 of introduction rules;
  6133 
  6134 * Provers/simplifier: 'simplified' attribute may refer to explicit
  6135 rules instead of full simplifier context; 'iff' attribute handles
  6136 conditional rules;
  6137 
  6138 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  6139 
  6140 * HOL: 'recdef' now fails on unfinished automated proofs, use
  6141 "(permissive)" option to recover old behavior;
  6142 
  6143 * HOL: 'inductive' no longer features separate (collective) attributes
  6144 for 'intros' (was found too confusing);
  6145 
  6146 * HOL: properly declared induction rules less_induct and
  6147 wf_induct_rule;
  6148 
  6149 
  6150 *** HOL ***
  6151 
  6152 * HOL: moved over to sane numeral syntax; the new policy is as
  6153 follows:
  6154 
  6155   - 0 and 1 are polymorphic constants, which are defined on any
  6156   numeric type (nat, int, real etc.);
  6157 
  6158   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  6159   binary representation internally;
  6160 
  6161   - type nat has special constructor Suc, and generally prefers Suc 0
  6162   over 1::nat and Suc (Suc 0) over 2::nat;
  6163 
  6164 This change may cause significant problems of INCOMPATIBILITY; here
  6165 are some hints on converting existing sources:
  6166 
  6167   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  6168   entities, so expressions involving "-" (unary or binary minus) need
  6169   to be spaced properly;
  6170 
  6171   - existing occurrences of "1" may need to be constraint "1::nat" or
  6172   even replaced by Suc 0; similar for old "2";
  6173 
  6174   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  6175 
  6176   - remove all special provisions on numerals in proofs;
  6177 
  6178 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  6179 representation (depends on bin_arith_simps in the default context);
  6180 
  6181 * HOL: symbolic syntax for x^2 (numeral 2);
  6182 
  6183 * HOL: the class of all HOL types is now called "type" rather than
  6184 "term"; INCOMPATIBILITY, need to adapt references to this type class
  6185 in axclass/classes, instance/arities, and (usually rare) occurrences
  6186 in typings (of consts etc.); internally the class is called
  6187 "HOL.type", ML programs should refer to HOLogic.typeS;
  6188 
  6189 * HOL/record package improvements:
  6190   - new derived operations "fields" to build a partial record section,
  6191     "extend" to promote a fixed record to a record scheme, and
  6192     "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*
  6193     declared as simp by default;
  6194   - shared operations ("more", "fields", etc.) now need to be always
  6195     qualified) --- potential INCOMPATIBILITY;
  6196   - removed "make_scheme" operations (use "make" with "extend") --
  6197     INCOMPATIBILITY;
  6198   - removed "more" class (simply use "term") -- INCOMPATIBILITY;
  6199   - provides cases/induct rules for use with corresponding Isar
  6200     methods (for concrete records, record schemes, concrete more
  6201     parts, and schematic more parts -- in that order);
  6202   - internal definitions directly based on a light-weight abstract
  6203     theory of product types over typedef rather than datatype;
  6204 
  6205 * HOL: generic code generator for generating executable ML code from
  6206 specifications; specific support for HOL constructs such as inductive
  6207 datatypes and sets, as well as recursive functions; can be invoked
  6208 via 'generate_code' theory section;
  6209 
  6210 * HOL: canonical cases/induct rules for n-tuples (n = 3..7);
  6211 
  6212 * HOL: consolidated and renamed several theories.  In particular:
  6213         Ord.thy has been absorbed into HOL.thy
  6214         String.thy has been absorbed into List.thy
  6215 
  6216 * HOL: concrete setsum syntax "\<Sum>i:A. b" == "setsum (%i. b) A"
  6217 (beware of argument permutation!);
  6218 
  6219 * HOL: linorder_less_split superseded by linorder_cases;
  6220 
  6221 * HOL/List: "nodups" renamed to "distinct";
  6222 
  6223 * HOL: added "The" definite description operator; move Hilbert's "Eps"
  6224 to peripheral theory "Hilbert_Choice"; some INCOMPATIBILITIES:
  6225   - Ex_def has changed, now need to use some_eq_ex
  6226 
  6227 * HOL: made split_all_tac safe; EXISTING PROOFS MAY FAIL OR LOOP, so
  6228 in this (rare) case use:
  6229 
  6230   delSWrapper "split_all_tac"