NEWS
author wenzelm
Thu Apr 28 21:06:04 2011 +0200 (2011-04-28)
changeset 42502 13b41fb77649
parent 42484 2777a27506d0
child 42514 f32500b4bc23
permissions -rw-r--r--
literal facts `prop` may contain dummy patterns;
     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 * Literal facts `prop` may contain dummy patterns, e.g. `_ = _`.  Note
    48 that the result needs to be unique, which means fact specifications
    49 may have to be refined after enriching a proof context.
    50 
    51 
    52 *** HOL ***
    53 
    54 * Nitpick:
    55   - Added "need" and "total_consts" options.
    56   - Reintroduced "show_skolems" option by popular demand.
    57   - Renamed attribute: nitpick_def ~> nitpick_unfold.
    58     INCOMPATIBILITY.
    59 
    60 * Sledgehammer:
    61   - sledgehammer available_provers ~> sledgehammer supported_provers
    62     INCOMPATIBILITY.
    63   - Added "monomorphize", "monomorphize_limit", and "type_sys" options.
    64 
    65 * "try":
    66   - Added "simp:", "intro:", and "elim:" options.
    67 
    68 * Quickcheck:
    69   - Added "eval" option to evaluate terms for the found counterexample
    70     (currently only supported by the default (exhaustive) tester)
    71   - Added post-processing of terms to obtain readable counterexamples
    72     (currently only supported by the default (exhaustive) tester)
    73 
    74 * Function package: discontinued option "tailrec".
    75 INCOMPATIBILITY. Use partial_function instead.
    76 
    77 * HOL-Probability:
    78   - Caratheodory's extension lemma is now proved for ring_of_sets.
    79   - Infinite products of probability measures are now available.
    80   - Use extended reals instead of positive extended reals.
    81     INCOMPATIBILITY.
    82 
    83 
    84 *** Document preparation ***
    85 
    86 * New term style "isub" as ad-hoc conversion of variables x1, y23 into
    87 subscripted form x\<^isub>1, y\<^isub>2\<^isub>3.
    88 
    89 * Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
    90 (e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).
    91 
    92 
    93 *** ML ***
    94 
    95 * Structure Proof_Context follows standard naming scheme.  Old
    96 ProofContext is still available for some time as legacy alias.
    97 
    98 * Structure Timing provides various operations for timing; supersedes
    99 former start_timing/end_timing etc.
   100 
   101 * Path.print is the official way to show file-system paths to users
   102 (including quotes etc.).
   103 
   104 * Inner syntax: identifiers in parse trees of generic categories
   105 "logic", "aprop", "idt" etc. carry position information (disguised as
   106 type constraints).  Occasional INCOMPATIBILITY with non-compliant
   107 translations that choke on unexpected type constraints.  Positions can
   108 be stripped in ML translations via Syntax.strip_positions /
   109 Syntax.strip_positions_ast, or via the syntax constant
   110 "_strip_positions" within parse trees.  As last resort, positions can
   111 be disabled via the configuration option Syntax.positions, which is
   112 called "syntax_positions" in Isar attribute syntax.
   113 
   114 * Discontinued special status of various ML structures that contribute
   115 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
   116 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
   117 refer directly to Ast.Constant, Lexicon.is_identifier,
   118 Syntax_Trans.mk_binder_tr etc.
   119 
   120 * Typed print translation: discontinued show_sorts argument, which is
   121 already available via context of "advanced" translation.
   122 
   123 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
   124 goal states; body tactic needs to address all subgoals uniformly.
   125 
   126 * Slightly more special eq_list/eq_set, with shortcut involving
   127 pointer equality (assumes that eq relation is reflexive).
   128 
   129 
   130 
   131 New in Isabelle2011 (January 2011)
   132 ----------------------------------
   133 
   134 *** General ***
   135 
   136 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
   137 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
   138 useful tooltips and hyperlinks produced from its static analysis.  The
   139 bundled component provides an executable Isabelle tool that can be run
   140 like this:
   141 
   142   Isabelle2011/bin/isabelle jedit
   143 
   144 * Significantly improved Isabelle/Isar implementation manual.
   145 
   146 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
   147 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
   148 while the default heap location within that directory lacks that extra
   149 suffix.  This isolates multiple Isabelle installations from each
   150 other, avoiding problems with old settings in new versions.
   151 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
   152 
   153 * Source files are always encoded as UTF-8, instead of old-fashioned
   154 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
   155 the following package declarations:
   156 
   157   \usepackage[utf8]{inputenc}
   158   \usepackage{textcomp}
   159 
   160 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
   161 a Unicode character is treated as a single symbol, not a sequence of
   162 non-ASCII bytes as before.  Since Isabelle/ML string literals may
   163 contain symbols without further backslash escapes, Unicode can now be
   164 used here as well.  Recall that Symbol.explode in ML provides a
   165 consistent view on symbols, while raw explode (or String.explode)
   166 merely give a byte-oriented representation.
   167 
   168 * Theory loader: source files are primarily located via the master
   169 directory of each theory node (where the .thy file itself resides).
   170 The global load path is still partially available as legacy feature.
   171 Minor INCOMPATIBILITY due to subtle change in file lookup: use
   172 explicit paths, relatively to the theory.
   173 
   174 * Special treatment of ML file names has been discontinued.
   175 Historically, optional extensions .ML or .sml were added on demand --
   176 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
   177 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
   178 
   179 * Various options that affect pretty printing etc. are now properly
   180 handled within the context via configuration options, instead of
   181 unsynchronized references or print modes.  There are both ML Config.T
   182 entities and Isar declaration attributes to access these.
   183 
   184   ML (Config.T)                 Isar (attribute)
   185 
   186   eta_contract                  eta_contract
   187   show_brackets                 show_brackets
   188   show_sorts                    show_sorts
   189   show_types                    show_types
   190   show_question_marks           show_question_marks
   191   show_consts                   show_consts
   192   show_abbrevs                  show_abbrevs
   193 
   194   Syntax.ast_trace              syntax_ast_trace
   195   Syntax.ast_stat               syntax_ast_stat
   196   Syntax.ambiguity_level        syntax_ambiguity_level
   197 
   198   Goal_Display.goals_limit      goals_limit
   199   Goal_Display.show_main_goal   show_main_goal
   200 
   201   Method.rule_trace             rule_trace
   202 
   203   Thy_Output.display            thy_output_display
   204   Thy_Output.quotes             thy_output_quotes
   205   Thy_Output.indent             thy_output_indent
   206   Thy_Output.source             thy_output_source
   207   Thy_Output.break              thy_output_break
   208 
   209 Note that corresponding "..._default" references in ML may only be
   210 changed globally at the ROOT session setup, but *not* within a theory.
   211 The option "show_abbrevs" supersedes the former print mode
   212 "no_abbrevs" with inverted meaning.
   213 
   214 * More systematic naming of some configuration options.
   215 INCOMPATIBILITY.
   216 
   217   trace_simp  ~>  simp_trace
   218   debug_simp  ~>  simp_debug
   219 
   220 * Support for real valued configuration options, using simplistic
   221 floating-point notation that coincides with the inner syntax for
   222 float_token.
   223 
   224 * Support for real valued preferences (with approximative PGIP type):
   225 front-ends need to accept "pgint" values in float notation.
   226 INCOMPATIBILITY.
   227 
   228 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
   229 DejaVu Sans.
   230 
   231 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   232 
   233 
   234 *** Pure ***
   235 
   236 * Command 'type_synonym' (with single argument) replaces somewhat
   237 outdated 'types', which is still available as legacy feature for some
   238 time.
   239 
   240 * Command 'nonterminal' (with 'and' separated list of arguments)
   241 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
   242 
   243 * Command 'notepad' replaces former 'example_proof' for
   244 experimentation in Isar without any result.  INCOMPATIBILITY.
   245 
   246 * Locale interpretation commands 'interpret' and 'sublocale' accept
   247 lists of equations to map definitions in a locale to appropriate
   248 entities in the context of the interpretation.  The 'interpretation'
   249 command already provided this functionality.
   250 
   251 * Diagnostic command 'print_dependencies' prints the locale instances
   252 that would be activated if the specified expression was interpreted in
   253 the current context.  Variant "print_dependencies!" assumes a context
   254 without interpretations.
   255 
   256 * Diagnostic command 'print_interps' prints interpretations in proofs
   257 in addition to interpretations in theories.
   258 
   259 * Discontinued obsolete 'global' and 'local' commands to manipulate
   260 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
   261 Sign.root_path and Sign.local_path may be applied directly where this
   262 feature is still required for historical reasons.
   263 
   264 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
   265 'definition' instead.
   266 
   267 * The "prems" fact, which refers to the accidental collection of
   268 foundational premises in the context, is now explicitly marked as
   269 legacy feature and will be discontinued soon.  Consider using "assms"
   270 of the head statement or reference facts by explicit names.
   271 
   272 * Document antiquotations @{class} and @{type} print classes and type
   273 constructors.
   274 
   275 * Document antiquotation @{file} checks file/directory entries within
   276 the local file system.
   277 
   278 
   279 *** HOL ***
   280 
   281 * Coercive subtyping: functions can be declared as coercions and type
   282 inference will add them as necessary upon input of a term.  Theory
   283 Complex_Main declares real :: nat => real and real :: int => real as
   284 coercions. A coercion function f is declared like this:
   285 
   286   declare [[coercion f]]
   287 
   288 To lift coercions through type constructors (e.g. from nat => real to
   289 nat list => real list), map functions can be declared, e.g.
   290 
   291   declare [[coercion_map map]]
   292 
   293 Currently coercion inference is activated only in theories including
   294 real numbers, i.e. descendants of Complex_Main.  This is controlled by
   295 the configuration option "coercion_enabled", e.g. it can be enabled in
   296 other theories like this:
   297 
   298   declare [[coercion_enabled]]
   299 
   300 * Command 'partial_function' provides basic support for recursive
   301 function definitions over complete partial orders.  Concrete instances
   302 are provided for i) the option type, ii) tail recursion on arbitrary
   303 types, and iii) the heap monad of Imperative_HOL.  See
   304 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
   305 for examples.
   306 
   307 * Function package: f.psimps rules are no longer implicitly declared
   308 as [simp].  INCOMPATIBILITY.
   309 
   310 * Datatype package: theorems generated for executable equality (class
   311 "eq") carry proper names and are treated as default code equations.
   312 
   313 * Inductive package: now offers command 'inductive_simps' to
   314 automatically derive instantiated and simplified equations for
   315 inductive predicates, similar to 'inductive_cases'.
   316 
   317 * Command 'enriched_type' allows to register properties of the
   318 functorial structure of types.
   319 
   320 * Improved infrastructure for term evaluation using code generator
   321 techniques, in particular static evaluation conversions.
   322 
   323 * Code generator: Scala (2.8 or higher) has been added to the target
   324 languages.
   325 
   326 * Code generator: globbing constant expressions "*" and "Theory.*"
   327 have been replaced by the more idiomatic "_" and "Theory._".
   328 INCOMPATIBILITY.
   329 
   330 * Code generator: export_code without explicit file declaration prints
   331 to standard output.  INCOMPATIBILITY.
   332 
   333 * Code generator: do not print function definitions for case
   334 combinators any longer.
   335 
   336 * Code generator: simplification with rules determined with
   337 src/Tools/Code/code_simp.ML and method "code_simp".
   338 
   339 * Code generator for records: more idiomatic representation of record
   340 types.  Warning: records are not covered by ancient SML code
   341 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
   342 rep_datatype declaration helps to succeed then:
   343 
   344   record 'a foo = ...
   345   ...
   346   rep_datatype foo_ext ...
   347 
   348 * Records: logical foundation type for records does not carry a
   349 '_type' suffix any longer (obsolete due to authentic syntax).
   350 INCOMPATIBILITY.
   351 
   352 * Quickcheck now by default uses exhaustive testing instead of random
   353 testing.  Random testing can be invoked by "quickcheck [random]",
   354 exhaustive testing by "quickcheck [exhaustive]".
   355 
   356 * Quickcheck instantiates polymorphic types with small finite
   357 datatypes by default. This enables a simple execution mechanism to
   358 handle quantifiers and function equality over the finite datatypes.
   359 
   360 * Quickcheck random generator has been renamed from "code" to
   361 "random".  INCOMPATIBILITY.
   362 
   363 * Quickcheck now has a configurable time limit which is set to 30
   364 seconds by default. This can be changed by adding [timeout = n] to the
   365 quickcheck command. The time limit for Auto Quickcheck is still set
   366 independently.
   367 
   368 * Quickcheck in locales considers interpretations of that locale for
   369 counter example search.
   370 
   371 * Sledgehammer:
   372   - Added "smt" and "remote_smt" provers based on the "smt" proof
   373     method. See the Sledgehammer manual for details ("isabelle doc
   374     sledgehammer").
   375   - Renamed commands:
   376     sledgehammer atp_info ~> sledgehammer running_provers
   377     sledgehammer atp_kill ~> sledgehammer kill_provers
   378     sledgehammer available_atps ~> sledgehammer available_provers
   379     INCOMPATIBILITY.
   380   - Renamed options:
   381     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
   382     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
   383     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
   384     (and "ms" and "min" are no longer supported)
   385     INCOMPATIBILITY.
   386 
   387 * Nitpick:
   388   - Renamed options:
   389     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
   390     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
   391     INCOMPATIBILITY.
   392   - Added support for partial quotient types.
   393   - Added local versions of the "Nitpick.register_xxx" functions.
   394   - Added "whack" option.
   395   - Allow registration of quotient types as codatatypes.
   396   - Improved "merge_type_vars" option to merge more types.
   397   - Removed unsound "fast_descrs" option.
   398   - Added custom symmetry breaking for datatypes, making it possible to reach
   399     higher cardinalities.
   400   - Prevent the expansion of too large definitions.
   401 
   402 * Proof methods "metis" and "meson" now have configuration options
   403 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
   404 to diagnose these tools. E.g.
   405 
   406     using [[metis_trace = true]]
   407 
   408 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
   409 manually as command 'solve_direct'.
   410 
   411 * The default SMT solver Z3 must be enabled explicitly (due to
   412 licensing issues) by setting the environment variable
   413 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
   414 commercial applications, the SMT solver CVC3 is provided as fall-back;
   415 changing the SMT solver is done via the configuration option
   416 "smt_solver".
   417 
   418 * Remote SMT solvers need to be referred to by the "remote_" prefix,
   419 i.e. "remote_cvc3" and "remote_z3".
   420 
   421 * Added basic SMT support for datatypes, records, and typedefs using
   422 the oracle mode (no proofs).  Direct support of pairs has been dropped
   423 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
   424 support for a similar behavior).  Minor INCOMPATIBILITY.
   425 
   426 * Changed SMT configuration options:
   427   - Renamed:
   428     z3_proofs ~> smt_oracle (with inverted meaning)
   429     z3_trace_assms ~> smt_trace_used_facts
   430     INCOMPATIBILITY.
   431   - Added:
   432     smt_verbose
   433     smt_random_seed
   434     smt_datatypes
   435     smt_infer_triggers
   436     smt_monomorph_limit
   437     cvc3_options
   438     remote_cvc3_options
   439     remote_z3_options
   440     yices_options
   441 
   442 * Boogie output files (.b2i files) need to be declared in the theory
   443 header.
   444 
   445 * Simplification procedure "list_to_set_comprehension" rewrites list
   446 comprehensions applied to List.set to set comprehensions.  Occasional
   447 INCOMPATIBILITY, may be deactivated like this:
   448 
   449   declare [[simproc del: list_to_set_comprehension]]
   450 
   451 * Removed old version of primrec package.  INCOMPATIBILITY.
   452 
   453 * Removed simplifier congruence rule of "prod_case", as has for long
   454 been the case with "split".  INCOMPATIBILITY.
   455 
   456 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
   457 
   458 * Removed [split_format ... and ... and ...] version of
   459 [split_format].  Potential INCOMPATIBILITY.
   460 
   461 * Predicate "sorted" now defined inductively, with nice induction
   462 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
   463 
   464 * Constant "contents" renamed to "the_elem", to free the generic name
   465 contents for other uses.  INCOMPATIBILITY.
   466 
   467 * Renamed class eq and constant eq (for code generation) to class
   468 equal and constant equal, plus renaming of related facts and various
   469 tuning.  INCOMPATIBILITY.
   470 
   471 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
   472 
   473 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
   474 INCOMPATIBILITY.
   475 
   476 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
   477 avoid confusion with finite sets.  INCOMPATIBILITY.
   478 
   479 * Abandoned locales equiv, congruent and congruent2 for equivalence
   480 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
   481 for congruent(2)).
   482 
   483 * Some previously unqualified names have been qualified:
   484 
   485   types
   486     bool ~> HOL.bool
   487     nat ~> Nat.nat
   488 
   489   constants
   490     Trueprop ~> HOL.Trueprop
   491     True ~> HOL.True
   492     False ~> HOL.False
   493     op & ~> HOL.conj
   494     op | ~> HOL.disj
   495     op --> ~> HOL.implies
   496     op = ~> HOL.eq
   497     Not ~> HOL.Not
   498     The ~> HOL.The
   499     All ~> HOL.All
   500     Ex ~> HOL.Ex
   501     Ex1 ~> HOL.Ex1
   502     Let ~> HOL.Let
   503     If ~> HOL.If
   504     Ball ~> Set.Ball
   505     Bex ~> Set.Bex
   506     Suc ~> Nat.Suc
   507     Pair ~> Product_Type.Pair
   508     fst ~> Product_Type.fst
   509     snd ~> Product_Type.snd
   510     curry ~> Product_Type.curry
   511     op : ~> Set.member
   512     Collect ~> Set.Collect
   513 
   514 INCOMPATIBILITY.
   515 
   516 * More canonical naming convention for some fundamental definitions:
   517 
   518     bot_bool_eq ~> bot_bool_def
   519     top_bool_eq ~> top_bool_def
   520     inf_bool_eq ~> inf_bool_def
   521     sup_bool_eq ~> sup_bool_def
   522     bot_fun_eq  ~> bot_fun_def
   523     top_fun_eq  ~> top_fun_def
   524     inf_fun_eq  ~> inf_fun_def
   525     sup_fun_eq  ~> sup_fun_def
   526 
   527 INCOMPATIBILITY.
   528 
   529 * More stylized fact names:
   530 
   531   expand_fun_eq ~> fun_eq_iff
   532   expand_set_eq ~> set_eq_iff
   533   set_ext       ~> set_eqI
   534   nat_number    ~> eval_nat_numeral
   535 
   536 INCOMPATIBILITY.
   537 
   538 * Refactoring of code-generation specific operations in theory List:
   539 
   540   constants
   541     null ~> List.null
   542 
   543   facts
   544     mem_iff ~> member_def
   545     null_empty ~> null_def
   546 
   547 INCOMPATIBILITY.  Note that these were not supposed to be used
   548 regularly unless for striking reasons; their main purpose was code
   549 generation.
   550 
   551 Various operations from the Haskell prelude are used for generating
   552 Haskell code.
   553 
   554 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
   555 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
   556 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
   557 
   558 * Abolished some non-alphabetic type names: "prod" and "sum" replace
   559 "*" and "+" respectively.  INCOMPATIBILITY.
   560 
   561 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
   562 "Sum_Type.Plus" instead.
   563 
   564 * Constant "split" has been merged with constant "prod_case"; names of
   565 ML functions, facts etc. involving split have been retained so far,
   566 though.  INCOMPATIBILITY.
   567 
   568 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
   569 instead.  INCOMPATIBILITY.
   570 
   571 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
   572 INCOMPATIBILITY.
   573 
   574 * Former theory Library/Enum is now part of the HOL-Main image.
   575 INCOMPATIBILITY: all constants of the Enum theory now have to be
   576 referred to by its qualified name.
   577 
   578   enum    ~>  Enum.enum
   579   nlists  ~>  Enum.nlists
   580   product ~>  Enum.product
   581 
   582 * Theory Library/Monad_Syntax provides do-syntax for monad types.
   583 Syntax in Library/State_Monad has been changed to avoid ambiguities.
   584 INCOMPATIBILITY.
   585 
   586 * Theory Library/SetsAndFunctions has been split into
   587 Library/Function_Algebras and Library/Set_Algebras; canonical names
   588 for instance definitions for functions; various improvements.
   589 INCOMPATIBILITY.
   590 
   591 * Theory Library/Multiset provides stable quicksort implementation of
   592 sort_key.
   593 
   594 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
   595 INCOMPATIBILITY.
   596 
   597 * Session Multivariate_Analysis: introduced a type class for euclidean
   598 space.  Most theorems are now stated in terms of euclidean spaces
   599 instead of finite cartesian products.
   600 
   601   types
   602     real ^ 'n ~>  'a::real_vector
   603               ~>  'a::euclidean_space
   604               ~>  'a::ordered_euclidean_space
   605         (depends on your needs)
   606 
   607   constants
   608      _ $ _        ~> _ $$ _
   609      \<chi> x. _  ~> \<chi>\<chi> x. _
   610      CARD('n)     ~> DIM('a)
   611 
   612 Also note that the indices are now natural numbers and not from some
   613 finite type. Finite cartesian products of euclidean spaces, products
   614 of euclidean spaces the real and complex numbers are instantiated to
   615 be euclidean_spaces.  INCOMPATIBILITY.
   616 
   617 * Session Probability: introduced pextreal as positive extended real
   618 numbers.  Use pextreal as value for measures.  Introduce the
   619 Radon-Nikodym derivative, product spaces and Fubini's theorem for
   620 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
   621 the integral in Multivariate Analysis.  INCOMPATIBILITY.
   622 
   623 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   624 INCOMPATIBILITY.
   625 
   626 * Session SPARK (with image HOL-SPARK) provides commands to load and
   627 prove verification conditions generated by the SPARK Ada program
   628 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
   629 
   630 
   631 *** HOL-Algebra ***
   632 
   633 * Theorems for additive ring operations (locale abelian_monoid and
   634 descendants) are generated by interpretation from their multiplicative
   635 counterparts.  Names (in particular theorem names) have the mandatory
   636 qualifier 'add'.  Previous theorem names are redeclared for
   637 compatibility.
   638 
   639 * Structure "int_ring" is now an abbreviation (previously a
   640 definition).  This fits more natural with advanced interpretations.
   641 
   642 
   643 *** HOLCF ***
   644 
   645 * The domain package now runs in definitional mode by default: The
   646 former command 'new_domain' is now called 'domain'.  To use the domain
   647 package in its original axiomatic mode, use 'domain (unsafe)'.
   648 INCOMPATIBILITY.
   649 
   650 * The new class "domain" is now the default sort.  Class "predomain"
   651 is an unpointed version of "domain". Theories can be updated by
   652 replacing sort annotations as shown below.  INCOMPATIBILITY.
   653 
   654   'a::type ~> 'a::countable
   655   'a::cpo  ~> 'a::predomain
   656   'a::pcpo ~> 'a::domain
   657 
   658 * The old type class "rep" has been superseded by class "domain".
   659 Accordingly, users of the definitional package must remove any
   660 "default_sort rep" declarations.  INCOMPATIBILITY.
   661 
   662 * The domain package (definitional mode) now supports unpointed
   663 predomain argument types, as long as they are marked 'lazy'. (Strict
   664 arguments must be in class "domain".) For example, the following
   665 domain definition now works:
   666 
   667   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
   668 
   669 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
   670 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
   671 'a option, and 'a list.  Additionally, it configures fixrec and the
   672 domain package to work with these types.  For example:
   673 
   674   fixrec isInl :: "('a + 'b) u -> tr"
   675     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
   676 
   677   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
   678 
   679 * The "(permissive)" option of fixrec has been replaced with a
   680 per-equation "(unchecked)" option. See
   681 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
   682 
   683 * The "bifinite" class no longer fixes a constant "approx"; the class
   684 now just asserts that such a function exists.  INCOMPATIBILITY.
   685 
   686 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
   687 defines an embedding of type 'a defl into udom by default; instances
   688 of "bifinite" and "domain" classes are available in
   689 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
   690 
   691 * The syntax "REP('a)" has been replaced with "DEFL('a)".
   692 
   693 * The predicate "directed" has been removed.  INCOMPATIBILITY.
   694 
   695 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
   696 
   697 * The function "cprod_map" has been renamed to "prod_map".
   698 INCOMPATIBILITY.
   699 
   700 * The monadic bind operator on each powerdomain has new binder syntax
   701 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
   702 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
   703 
   704 * The infix syntax for binary union on each powerdomain has changed
   705 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
   706 syntax.  INCOMPATIBILITY.
   707 
   708 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
   709 still supported as an input translation.
   710 
   711 * Renamed some theorems (the original names are also still available).
   712 
   713   expand_fun_below   ~> fun_below_iff
   714   below_fun_ext      ~> fun_belowI
   715   expand_cfun_eq     ~> cfun_eq_iff
   716   ext_cfun           ~> cfun_eqI
   717   expand_cfun_below  ~> cfun_below_iff
   718   below_cfun_ext     ~> cfun_belowI
   719   cont2cont_Rep_CFun ~> cont2cont_APP
   720 
   721 * The Abs and Rep functions for various types have changed names.
   722 Related theorem names have also changed to match. INCOMPATIBILITY.
   723 
   724   Rep_CFun  ~> Rep_cfun
   725   Abs_CFun  ~> Abs_cfun
   726   Rep_Sprod ~> Rep_sprod
   727   Abs_Sprod ~> Abs_sprod
   728   Rep_Ssum  ~> Rep_ssum
   729   Abs_Ssum  ~> Abs_ssum
   730 
   731 * Lemmas with names of the form *_defined_iff or *_strict_iff have
   732 been renamed to *_bottom_iff.  INCOMPATIBILITY.
   733 
   734 * Various changes to bisimulation/coinduction with domain package:
   735 
   736   - Definitions of "bisim" constants no longer mention definedness.
   737   - With mutual recursion, "bisim" predicate is now curried.
   738   - With mutual recursion, each type gets a separate coind theorem.
   739   - Variable names in bisim_def and coinduct rules have changed.
   740 
   741 INCOMPATIBILITY.
   742 
   743 * Case combinators generated by the domain package for type "foo" are
   744 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
   745 
   746 * Several theorems have been renamed to more accurately reflect the
   747 names of constants and types involved.  INCOMPATIBILITY.
   748 
   749   thelub_const    ~> lub_const
   750   lub_const       ~> is_lub_const
   751   thelubI         ~> lub_eqI
   752   is_lub_lub      ~> is_lubD2
   753   lubI            ~> is_lub_lub
   754   unique_lub      ~> is_lub_unique
   755   is_ub_lub       ~> is_lub_rangeD1
   756   lub_bin_chain   ~> is_lub_bin_chain
   757   lub_fun         ~> is_lub_fun
   758   thelub_fun      ~> lub_fun
   759   thelub_cfun     ~> lub_cfun
   760   thelub_Pair     ~> lub_Pair
   761   lub_cprod       ~> is_lub_prod
   762   thelub_cprod    ~> lub_prod
   763   minimal_cprod   ~> minimal_prod
   764   inst_cprod_pcpo ~> inst_prod_pcpo
   765   UU_I            ~> bottomI
   766   compact_UU      ~> compact_bottom
   767   deflation_UU    ~> deflation_bottom
   768   finite_deflation_UU ~> finite_deflation_bottom
   769 
   770 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
   771 
   772   sq_ord_less_eq_trans ~> below_eq_trans
   773   sq_ord_eq_less_trans ~> eq_below_trans
   774   refl_less            ~> below_refl
   775   trans_less           ~> below_trans
   776   antisym_less         ~> below_antisym
   777   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
   778   box_less             ~> box_below
   779   rev_trans_less       ~> rev_below_trans
   780   not_less2not_eq      ~> not_below2not_eq
   781   less_UU_iff          ~> below_UU_iff
   782   flat_less_iff        ~> flat_below_iff
   783   adm_less             ~> adm_below
   784   adm_not_less         ~> adm_not_below
   785   adm_compact_not_less ~> adm_compact_not_below
   786   less_fun_def         ~> below_fun_def
   787   expand_fun_less      ~> fun_below_iff
   788   less_fun_ext         ~> fun_belowI
   789   less_discr_def       ~> below_discr_def
   790   discr_less_eq        ~> discr_below_eq
   791   less_unit_def        ~> below_unit_def
   792   less_cprod_def       ~> below_prod_def
   793   prod_lessI           ~> prod_belowI
   794   Pair_less_iff        ~> Pair_below_iff
   795   fst_less_iff         ~> fst_below_iff
   796   snd_less_iff         ~> snd_below_iff
   797   expand_cfun_less     ~> cfun_below_iff
   798   less_cfun_ext        ~> cfun_belowI
   799   injection_less       ~> injection_below
   800   less_up_def          ~> below_up_def
   801   not_Iup_less         ~> not_Iup_below
   802   Iup_less             ~> Iup_below
   803   up_less              ~> up_below
   804   Def_inject_less_eq   ~> Def_below_Def
   805   Def_less_is_eq       ~> Def_below_iff
   806   spair_less_iff       ~> spair_below_iff
   807   less_sprod           ~> below_sprod
   808   spair_less           ~> spair_below
   809   sfst_less_iff        ~> sfst_below_iff
   810   ssnd_less_iff        ~> ssnd_below_iff
   811   fix_least_less       ~> fix_least_below
   812   dist_less_one        ~> dist_below_one
   813   less_ONE             ~> below_ONE
   814   ONE_less_iff         ~> ONE_below_iff
   815   less_sinlD           ~> below_sinlD
   816   less_sinrD           ~> below_sinrD
   817 
   818 
   819 *** FOL and ZF ***
   820 
   821 * All constant names are now qualified internally and use proper
   822 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
   823 
   824 
   825 *** ML ***
   826 
   827 * Antiquotation @{assert} inlines a function bool -> unit that raises
   828 Fail if the argument is false.  Due to inlining the source position of
   829 failed assertions is included in the error output.
   830 
   831 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
   832 text is in practice always evaluated with a stable theory checkpoint.
   833 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
   834 
   835 * Antiquotation @{theory A} refers to theory A from the ancestry of
   836 the current context, not any accidental theory loader state as before.
   837 Potential INCOMPATIBILITY, subtle change in semantics.
   838 
   839 * Syntax.pretty_priority (default 0) configures the required priority
   840 of pretty-printed output and thus affects insertion of parentheses.
   841 
   842 * Syntax.default_root (default "any") configures the inner syntax
   843 category (nonterminal symbol) for parsing of terms.
   844 
   845 * Former exception Library.UnequalLengths now coincides with
   846 ListPair.UnequalLengths.
   847 
   848 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
   849 main functionality is provided by structure Simplifier.
   850 
   851 * Renamed raw "explode" function to "raw_explode" to emphasize its
   852 meaning.  Note that internally to Isabelle, Symbol.explode is used in
   853 almost all situations.
   854 
   855 * Discontinued obsolete function sys_error and exception SYS_ERROR.
   856 See implementation manual for further details on exceptions in
   857 Isabelle/ML.
   858 
   859 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
   860 meaning.
   861 
   862 * Renamed structure PureThy to Pure_Thy and moved most of its
   863 operations to structure Global_Theory, to emphasize that this is
   864 rarely-used global-only stuff.
   865 
   866 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
   867 instead (or tracing for high-volume output).
   868 
   869 * Configuration option show_question_marks only affects regular pretty
   870 printing of types and terms, not raw Term.string_of_vname.
   871 
   872 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
   873 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
   874 @{thms} for most purposes.
   875 
   876 * ML structure Unsynchronized is never opened, not even in Isar
   877 interaction mode as before.  Old Unsynchronized.set etc. have been
   878 discontinued -- use plain := instead.  This should be *rare* anyway,
   879 since modern tools always work via official context data, notably
   880 configuration options.
   881 
   882 * Parallel and asynchronous execution requires special care concerning
   883 interrupts.  Structure Exn provides some convenience functions that
   884 avoid working directly with raw Interrupt.  User code must not absorb
   885 interrupts -- intermediate handling (for cleanup etc.) needs to be
   886 followed by re-raising of the original exception.  Another common
   887 source of mistakes are "handle _" patterns, which make the meaning of
   888 the program subject to physical effects of the environment.
   889 
   890 
   891 
   892 New in Isabelle2009-2 (June 2010)
   893 ---------------------------------
   894 
   895 *** General ***
   896 
   897 * Authentic syntax for *all* logical entities (type classes, type
   898 constructors, term constants): provides simple and robust
   899 correspondence between formal entities and concrete syntax.  Within
   900 the parse tree / AST representations, "constants" are decorated by
   901 their category (class, type, const) and spelled out explicitly with
   902 their full internal name.
   903 
   904 Substantial INCOMPATIBILITY concerning low-level syntax declarations
   905 and translations (translation rules and translation functions in ML).
   906 Some hints on upgrading:
   907 
   908   - Many existing uses of 'syntax' and 'translations' can be replaced
   909     by more modern 'type_notation', 'notation' and 'abbreviation',
   910     which are independent of this issue.
   911 
   912   - 'translations' require markup within the AST; the term syntax
   913     provides the following special forms:
   914 
   915       CONST c   -- produces syntax version of constant c from context
   916       XCONST c  -- literally c, checked as constant from context
   917       c         -- literally c, if declared by 'syntax'
   918 
   919     Plain identifiers are treated as AST variables -- occasionally the
   920     system indicates accidental variables via the error "rhs contains
   921     extra variables".
   922 
   923     Type classes and type constructors are marked according to their
   924     concrete syntax.  Some old translations rules need to be written
   925     for the "type" category, using type constructor application
   926     instead of pseudo-term application of the default category
   927     "logic".
   928 
   929   - 'parse_translation' etc. in ML may use the following
   930     antiquotations:
   931 
   932       @{class_syntax c}   -- type class c within parse tree / AST
   933       @{term_syntax c}    -- type constructor c within parse tree / AST
   934       @{const_syntax c}   -- ML version of "CONST c" above
   935       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
   936 
   937   - Literal types within 'typed_print_translations', i.e. those *not*
   938     represented as pseudo-terms are represented verbatim.  Use @{class
   939     c} or @{type_name c} here instead of the above syntax
   940     antiquotations.
   941 
   942 Note that old non-authentic syntax was based on unqualified base
   943 names, so all of the above "constant" names would coincide.  Recall
   944 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
   945 diagnose syntax problems.
   946 
   947 * Type constructors admit general mixfix syntax, not just infix.
   948 
   949 * Concrete syntax may be attached to local entities without a proof
   950 body, too.  This works via regular mixfix annotations for 'fix',
   951 'def', 'obtain' etc. or via the explicit 'write' command, which is
   952 similar to the 'notation' command in theory specifications.
   953 
   954 * Discontinued unnamed infix syntax (legacy feature for many years) --
   955 need to specify constant name and syntax separately.  Internal ML
   956 datatype constructors have been renamed from InfixName to Infix etc.
   957 Minor INCOMPATIBILITY.
   958 
   959 * Schematic theorem statements need to be explicitly markup as such,
   960 via commands 'schematic_lemma', 'schematic_theorem',
   961 'schematic_corollary'.  Thus the relevance of the proof is made
   962 syntactically clear, which impacts performance in a parallel or
   963 asynchronous interactive environment.  Minor INCOMPATIBILITY.
   964 
   965 * Use of cumulative prems via "!" in some proof methods has been
   966 discontinued (old legacy feature).
   967 
   968 * References 'trace_simp' and 'debug_simp' have been replaced by
   969 configuration options stored in the context. Enabling tracing (the
   970 case of debugging is similar) in proofs works via
   971 
   972   using [[trace_simp = true]]
   973 
   974 Tracing is then active for all invocations of the simplifier in
   975 subsequent goal refinement steps. Tracing may also still be enabled or
   976 disabled via the ProofGeneral settings menu.
   977 
   978 * Separate commands 'hide_class', 'hide_type', 'hide_const',
   979 'hide_fact' replace the former 'hide' KIND command.  Minor
   980 INCOMPATIBILITY.
   981 
   982 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
   983 more efficient than combinations with -q1 or -q2.
   984 
   985 
   986 *** Pure ***
   987 
   988 * Proofterms record type-class reasoning explicitly, using the
   989 "unconstrain" operation internally.  This eliminates all sort
   990 constraints from a theorem and proof, introducing explicit
   991 OFCLASS-premises.  On the proof term level, this operation is
   992 automatically applied at theorem boundaries, such that closed proofs
   993 are always free of sort constraints.  INCOMPATIBILITY for tools that
   994 inspect proof terms.
   995 
   996 * Local theory specifications may depend on extra type variables that
   997 are not present in the result type -- arguments TYPE('a) :: 'a itself
   998 are added internally.  For example:
   999 
  1000   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
  1001 
  1002 * Predicates of locales introduced by classes carry a mandatory
  1003 "class" prefix.  INCOMPATIBILITY.
  1004 
  1005 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
  1006 
  1007 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
  1008 'class' instead.
  1009 
  1010 * Command 'code_reflect' allows to incorporate generated ML code into
  1011 runtime environment; replaces immature code_datatype antiquotation.
  1012 INCOMPATIBILITY.
  1013 
  1014 * Code generator: simple concept for abstract datatypes obeying
  1015 invariants.
  1016 
  1017 * Code generator: details of internal data cache have no impact on the
  1018 user space functionality any longer.
  1019 
  1020 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  1021 subgoals.  This is more appropriate for interpretations with 'where'.
  1022 INCOMPATIBILITY.
  1023 
  1024 * Command 'example_proof' opens an empty proof body.  This allows to
  1025 experiment with Isar, without producing any persistent result.
  1026 
  1027 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  1028 within a local theory context, with explicit checking of the
  1029 constructors involved (in contrast to the raw 'syntax' versions).
  1030 
  1031 * Commands 'types' and 'typedecl' now work within a local theory
  1032 context -- without introducing dependencies on parameters or
  1033 assumptions, which is not possible in Isabelle/Pure.
  1034 
  1035 * Command 'defaultsort' has been renamed to 'default_sort', it works
  1036 within a local theory context.  Minor INCOMPATIBILITY.
  1037 
  1038 
  1039 *** HOL ***
  1040 
  1041 * Command 'typedef' now works within a local theory context -- without
  1042 introducing dependencies on parameters or assumptions, which is not
  1043 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  1044 contain multiple interpretations of local typedefs (with different
  1045 non-emptiness proofs), even in a global theory context.
  1046 
  1047 * New package for quotient types.  Commands 'quotient_type' and
  1048 'quotient_definition' may be used for defining types and constants by
  1049 quotient constructions.  An example is the type of integers created by
  1050 quotienting pairs of natural numbers:
  1051 
  1052   fun
  1053     intrel :: "(nat * nat) => (nat * nat) => bool"
  1054   where
  1055     "intrel (x, y) (u, v) = (x + v = u + y)"
  1056 
  1057   quotient_type int = "nat * nat" / intrel
  1058     by (auto simp add: equivp_def expand_fun_eq)
  1059 
  1060   quotient_definition
  1061     "0::int" is "(0::nat, 0::nat)"
  1062 
  1063 The method "lifting" can be used to lift of theorems from the
  1064 underlying "raw" type to the quotient type.  The example
  1065 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  1066 construction and provides a reasoning infrastructure for finite sets.
  1067 
  1068 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  1069 clash with new theory Quotient in Main HOL.
  1070 
  1071 * Moved the SMT binding into the main HOL session, eliminating
  1072 separate HOL-SMT session.
  1073 
  1074 * List membership infix mem operation is only an input abbreviation.
  1075 INCOMPATIBILITY.
  1076 
  1077 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  1078 for future developements; former Library/Word.thy is still present in
  1079 the AFP entry RSAPPS.
  1080 
  1081 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  1082 longer shadowed.  INCOMPATIBILITY.
  1083 
  1084 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  1085 INCOMPATIBILITY.
  1086 
  1087 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  1088 INCOMPATIBILITY.
  1089 
  1090 * Dropped normalizing_semiring etc; use the facts in semiring classes
  1091 instead.  INCOMPATIBILITY.
  1092 
  1093 * Dropped several real-specific versions of lemmas about floor and
  1094 ceiling; use the generic lemmas from theory "Archimedean_Field"
  1095 instead.  INCOMPATIBILITY.
  1096 
  1097   floor_number_of_eq         ~> floor_number_of
  1098   le_floor_eq_number_of      ~> number_of_le_floor
  1099   le_floor_eq_zero           ~> zero_le_floor
  1100   le_floor_eq_one            ~> one_le_floor
  1101   floor_less_eq_number_of    ~> floor_less_number_of
  1102   floor_less_eq_zero         ~> floor_less_zero
  1103   floor_less_eq_one          ~> floor_less_one
  1104   less_floor_eq_number_of    ~> number_of_less_floor
  1105   less_floor_eq_zero         ~> zero_less_floor
  1106   less_floor_eq_one          ~> one_less_floor
  1107   floor_le_eq_number_of      ~> floor_le_number_of
  1108   floor_le_eq_zero           ~> floor_le_zero
  1109   floor_le_eq_one            ~> floor_le_one
  1110   floor_subtract_number_of   ~> floor_diff_number_of
  1111   floor_subtract_one         ~> floor_diff_one
  1112   ceiling_number_of_eq       ~> ceiling_number_of
  1113   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  1114   ceiling_le_zero_eq         ~> ceiling_le_zero
  1115   ceiling_le_eq_one          ~> ceiling_le_one
  1116   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  1117   less_ceiling_eq_zero       ~> zero_less_ceiling
  1118   less_ceiling_eq_one        ~> one_less_ceiling
  1119   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  1120   ceiling_less_eq_zero       ~> ceiling_less_zero
  1121   ceiling_less_eq_one        ~> ceiling_less_one
  1122   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  1123   le_ceiling_eq_zero         ~> zero_le_ceiling
  1124   le_ceiling_eq_one          ~> one_le_ceiling
  1125   ceiling_subtract_number_of ~> ceiling_diff_number_of
  1126   ceiling_subtract_one       ~> ceiling_diff_one
  1127 
  1128 * Theory "Finite_Set": various folding_XXX locales facilitate the
  1129 application of the various fold combinators on finite sets.
  1130 
  1131 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  1132 provides abstract red-black tree type which is backed by "RBT_Impl" as
  1133 implementation.  INCOMPATIBILTY.
  1134 
  1135 * Theory Library/Coinductive_List has been removed -- superseded by
  1136 AFP/thys/Coinductive.
  1137 
  1138 * Theory PReal, including the type "preal" and related operations, has
  1139 been removed.  INCOMPATIBILITY.
  1140 
  1141 * Real: new development using Cauchy Sequences.
  1142 
  1143 * Split off theory "Big_Operators" containing setsum, setprod,
  1144 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  1145 
  1146 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  1147 "Int" etc.  INCOMPATIBILITY.
  1148 
  1149 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  1150 
  1151 * New set of rules "ac_simps" provides combined assoc / commute
  1152 rewrites for all interpretations of the appropriate generic locales.
  1153 
  1154 * Renamed theory "OrderedGroup" to "Groups" and split theory
  1155 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  1156 appropriate and more consistent names suitable for name prefixes
  1157 within the HOL theories.  INCOMPATIBILITY.
  1158 
  1159 * Some generic constants have been put to appropriate theories:
  1160   - less_eq, less: Orderings
  1161   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  1162   - inverse, divide: Rings
  1163 INCOMPATIBILITY.
  1164 
  1165 * More consistent naming of type classes involving orderings (and
  1166 lattices):
  1167 
  1168     lower_semilattice                   ~> semilattice_inf
  1169     upper_semilattice                   ~> semilattice_sup
  1170 
  1171     dense_linear_order                  ~> dense_linorder
  1172 
  1173     pordered_ab_group_add               ~> ordered_ab_group_add
  1174     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  1175     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  1176     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  1177     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  1178     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  1179     pordered_cancel_semiring            ~> ordered_cancel_semiring
  1180     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  1181     pordered_comm_ring                  ~> ordered_comm_ring
  1182     pordered_comm_semiring              ~> ordered_comm_semiring
  1183     pordered_ring                       ~> ordered_ring
  1184     pordered_ring_abs                   ~> ordered_ring_abs
  1185     pordered_semiring                   ~> ordered_semiring
  1186 
  1187     ordered_ab_group_add                ~> linordered_ab_group_add
  1188     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  1189     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  1190     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  1191     ordered_field                       ~> linordered_field
  1192     ordered_field_no_lb                 ~> linordered_field_no_lb
  1193     ordered_field_no_ub                 ~> linordered_field_no_ub
  1194     ordered_field_dense_linear_order    ~> dense_linordered_field
  1195     ordered_idom                        ~> linordered_idom
  1196     ordered_ring                        ~> linordered_ring
  1197     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  1198     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  1199     ordered_ring_strict                 ~> linordered_ring_strict
  1200     ordered_semidom                     ~> linordered_semidom
  1201     ordered_semiring                    ~> linordered_semiring
  1202     ordered_semiring_1                  ~> linordered_semiring_1
  1203     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  1204     ordered_semiring_strict             ~> linordered_semiring_strict
  1205 
  1206   The following slightly odd type classes have been moved to a
  1207   separate theory Library/Lattice_Algebras:
  1208 
  1209     lordered_ab_group_add               ~> lattice_ab_group_add
  1210     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  1211     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  1212     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  1213     lordered_ring                       ~> lattice_ring
  1214 
  1215 INCOMPATIBILITY.
  1216 
  1217 * Refined field classes:
  1218   - classes division_ring_inverse_zero, field_inverse_zero,
  1219     linordered_field_inverse_zero include rule inverse 0 = 0 --
  1220     subsumes former division_by_zero class;
  1221   - numerous lemmas have been ported from field to division_ring.
  1222 INCOMPATIBILITY.
  1223 
  1224 * Refined algebra theorem collections:
  1225   - dropped theorem group group_simps, use algebra_simps instead;
  1226   - dropped theorem group ring_simps, use field_simps instead;
  1227   - proper theorem collection field_simps subsumes former theorem
  1228     groups field_eq_simps and field_simps;
  1229   - dropped lemma eq_minus_self_iff which is a duplicate for
  1230     equal_neg_zero.
  1231 INCOMPATIBILITY.
  1232 
  1233 * Theory Finite_Set and List: some lemmas have been generalized from
  1234 sets to lattices:
  1235 
  1236   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  1237   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  1238   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  1239   union_Union_fold_union        ~> sup_Sup_fold_sup
  1240   Inter_fold_inter              ~> Inf_fold_inf
  1241   Union_fold_union              ~> Sup_fold_sup
  1242   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  1243   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  1244   INTER_fold_inter              ~> INFI_fold_inf
  1245   UNION_fold_union              ~> SUPR_fold_sup
  1246 
  1247 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  1248 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  1249 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  1250 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  1251 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  1252 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  1253 
  1254 * Reorganized theory Multiset: swapped notation of pointwise and
  1255 multiset order:
  1256 
  1257   - pointwise ordering is instance of class order with standard syntax
  1258     <= and <;
  1259   - multiset ordering has syntax <=# and <#; partial order properties
  1260     are provided by means of interpretation with prefix
  1261     multiset_order;
  1262   - less duplication, less historical organization of sections,
  1263     conversion from associations lists to multisets, rudimentary code
  1264     generation;
  1265   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  1266     if needed.
  1267 
  1268 Renamed:
  1269 
  1270   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  1271   multi_count_ext  ~>  multiset_ext
  1272   diff_union_inverse2  ~>  diff_union_cancelR
  1273 
  1274 INCOMPATIBILITY.
  1275 
  1276 * Theory Permutation: replaced local "remove" by List.remove1.
  1277 
  1278 * Code generation: ML and OCaml code is decorated with signatures.
  1279 
  1280 * Theory List: added transpose.
  1281 
  1282 * Library/Nat_Bijection.thy is a collection of bijective functions
  1283 between nat and other types, which supersedes the older libraries
  1284 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  1285 
  1286   Constants:
  1287   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  1288   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  1289   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  1290   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  1291   Countable.pair_encode           ~> prod_encode
  1292   NatIso.prod2nat                 ~> prod_encode
  1293   NatIso.nat2prod                 ~> prod_decode
  1294   NatIso.sum2nat                  ~> sum_encode
  1295   NatIso.nat2sum                  ~> sum_decode
  1296   NatIso.list2nat                 ~> list_encode
  1297   NatIso.nat2list                 ~> list_decode
  1298   NatIso.set2nat                  ~> set_encode
  1299   NatIso.nat2set                  ~> set_decode
  1300 
  1301   Lemmas:
  1302   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  1303   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  1304   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  1305   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  1306   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  1307   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  1308   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  1309   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  1310   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  1311   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  1312   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  1313   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  1314   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  1315 
  1316 * Sledgehammer:
  1317   - Renamed ATP commands:
  1318     atp_info     ~> sledgehammer running_atps
  1319     atp_kill     ~> sledgehammer kill_atps
  1320     atp_messages ~> sledgehammer messages
  1321     atp_minimize ~> sledgehammer minimize
  1322     print_atps   ~> sledgehammer available_atps
  1323     INCOMPATIBILITY.
  1324   - Added user's manual ("isabelle doc sledgehammer").
  1325   - Added option syntax and "sledgehammer_params" to customize
  1326     Sledgehammer's behavior.  See the manual for details.
  1327   - Modified the Isar proof reconstruction code so that it produces
  1328     direct proofs rather than proofs by contradiction.  (This feature
  1329     is still experimental.)
  1330   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  1331     full-typed mode.
  1332   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  1333 
  1334 * Nitpick:
  1335   - Added and implemented "binary_ints" and "bits" options.
  1336   - Added "std" option and implemented support for nonstandard models.
  1337   - Added and implemented "finitize" option to improve the precision
  1338     of infinite datatypes based on a monotonicity analysis.
  1339   - Added support for quotient types.
  1340   - Added support for "specification" and "ax_specification"
  1341     constructs.
  1342   - Added support for local definitions (for "function" and
  1343     "termination" proofs).
  1344   - Added support for term postprocessors.
  1345   - Optimized "Multiset.multiset" and "FinFun.finfun".
  1346   - Improved efficiency of "destroy_constrs" optimization.
  1347   - Fixed soundness bugs related to "destroy_constrs" optimization and
  1348     record getters.
  1349   - Fixed soundness bug related to higher-order constructors.
  1350   - Fixed soundness bug when "full_descrs" is enabled.
  1351   - Improved precision of set constructs.
  1352   - Added "atoms" option.
  1353   - Added cache to speed up repeated Kodkod invocations on the same
  1354     problems.
  1355   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  1356     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  1357     "SAT4J_Light".  INCOMPATIBILITY.
  1358   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  1359     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  1360   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  1361 
  1362 * Method "induct" now takes instantiations of the form t, where t is not
  1363   a variable, as a shorthand for "x == t", where x is a fresh variable.
  1364   If this is not intended, t has to be enclosed in parentheses.
  1365   By default, the equalities generated by definitional instantiations
  1366   are pre-simplified, which may cause parameters of inductive cases
  1367   to disappear, or may even delete some of the inductive cases.
  1368   Use "induct (no_simp)" instead of "induct" to restore the old
  1369   behaviour. The (no_simp) option is also understood by the "cases"
  1370   and "nominal_induct" methods, which now perform pre-simplification, too.
  1371   INCOMPATIBILITY.
  1372 
  1373 
  1374 *** HOLCF ***
  1375 
  1376 * Variable names in lemmas generated by the domain package have
  1377 changed; the naming scheme is now consistent with the HOL datatype
  1378 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  1379 
  1380 * The domain package no longer defines the function "foo_copy" for
  1381 recursive domain "foo".  The reach lemma is now stated directly in
  1382 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  1383 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  1384 
  1385 * Most definedness lemmas generated by the domain package (previously
  1386 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  1387 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  1388 Proofs that used definedness lemmas as intro rules may break,
  1389 potential INCOMPATIBILITY.
  1390 
  1391 * Induction and casedist rules generated by the domain package now
  1392 declare proper case_names (one called "bottom", and one named for each
  1393 constructor).  INCOMPATIBILITY.
  1394 
  1395 * For mutually-recursive domains, separate "reach" and "take_lemma"
  1396 rules are generated for each domain, INCOMPATIBILITY.
  1397 
  1398   foo_bar.reach       ~> foo.reach  bar.reach
  1399   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  1400 
  1401 * Some lemmas generated by the domain package have been renamed for
  1402 consistency with the datatype package, INCOMPATIBILITY.
  1403 
  1404   foo.ind        ~> foo.induct
  1405   foo.finite_ind ~> foo.finite_induct
  1406   foo.coind      ~> foo.coinduct
  1407   foo.casedist   ~> foo.exhaust
  1408   foo.exhaust    ~> foo.nchotomy
  1409 
  1410 * For consistency with other definition packages, the fixrec package
  1411 now generates qualified theorem names, INCOMPATIBILITY.
  1412 
  1413   foo_simps  ~> foo.simps
  1414   foo_unfold ~> foo.unfold
  1415   foo_induct ~> foo.induct
  1416 
  1417 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  1418 method and internal fixrec proofs now use the default simpset instead.
  1419 INCOMPATIBILITY.
  1420 
  1421 * The "contlub" predicate has been removed.  Proof scripts should use
  1422 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  1423 
  1424 * The "admw" predicate has been removed, INCOMPATIBILITY.
  1425 
  1426 * The constants cpair, cfst, and csnd have been removed in favor of
  1427 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  1428 
  1429 
  1430 *** ML ***
  1431 
  1432 * Antiquotations for basic formal entities:
  1433 
  1434     @{class NAME}         -- type class
  1435     @{class_syntax NAME}  -- syntax representation of the above
  1436 
  1437     @{type_name NAME}     -- logical type
  1438     @{type_abbrev NAME}   -- type abbreviation
  1439     @{nonterminal NAME}   -- type of concrete syntactic category
  1440     @{type_syntax NAME}   -- syntax representation of any of the above
  1441 
  1442     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  1443     @{const_abbrev NAME}  -- abbreviated constant
  1444     @{const_syntax NAME}  -- syntax representation of any of the above
  1445 
  1446 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  1447 syntax constant (cf. 'syntax' command).
  1448 
  1449 * Antiquotation @{make_string} inlines a function to print arbitrary
  1450 values similar to the ML toplevel.  The result is compiler dependent
  1451 and may fall back on "?" in certain situations.
  1452 
  1453 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  1454 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  1455 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  1456 not work with the asynchronous Isar document model.
  1457 
  1458 * Configuration options now admit dynamic default values, depending on
  1459 the context or even global references.
  1460 
  1461 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  1462 uses an efficient external library if available (for Poly/ML).
  1463 
  1464 * Renamed some important ML structures, while keeping the old names
  1465 for some time as aliases within the structure Legacy:
  1466 
  1467   OuterKeyword  ~>  Keyword
  1468   OuterLex      ~>  Token
  1469   OuterParse    ~>  Parse
  1470   OuterSyntax   ~>  Outer_Syntax
  1471   PrintMode     ~>  Print_Mode
  1472   SpecParse     ~>  Parse_Spec
  1473   ThyInfo       ~>  Thy_Info
  1474   ThyLoad       ~>  Thy_Load
  1475   ThyOutput     ~>  Thy_Output
  1476   TypeInfer     ~>  Type_Infer
  1477 
  1478 Note that "open Legacy" simplifies porting of sources, but forgetting
  1479 to remove it again will complicate porting again in the future.
  1480 
  1481 * Most operations that refer to a global context are named
  1482 accordingly, e.g. Simplifier.global_context or
  1483 ProofContext.init_global.  There are some situations where a global
  1484 context actually works, but under normal circumstances one needs to
  1485 pass the proper local context through the code!
  1486 
  1487 * Discontinued old TheoryDataFun with its copy/init operation -- data
  1488 needs to be pure.  Functor Theory_Data_PP retains the traditional
  1489 Pretty.pp argument to merge, which is absent in the standard
  1490 Theory_Data version.
  1491 
  1492 * Sorts.certify_sort and derived "cert" operations for types and terms
  1493 no longer minimize sorts.  Thus certification at the boundary of the
  1494 inference kernel becomes invariant under addition of class relations,
  1495 which is an important monotonicity principle.  Sorts are now minimized
  1496 in the syntax layer only, at the boundary between the end-user and the
  1497 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  1498 explicitly in rare situations.
  1499 
  1500 * Renamed old-style Drule.standard to Drule.export_without_context, to
  1501 emphasize that this is in no way a standard operation.
  1502 INCOMPATIBILITY.
  1503 
  1504 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  1505 usual for resolution.  Rare INCOMPATIBILITY.
  1506 
  1507 * Renamed varify/unvarify operations to varify_global/unvarify_global
  1508 to emphasize that these only work in a global situation (which is
  1509 quite rare).
  1510 
  1511 * Curried take and drop in library.ML; negative length is interpreted
  1512 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  1513 
  1514 * Proof terms: type substitutions on proof constants now use canonical
  1515 order of type variables.  INCOMPATIBILITY for tools working with proof
  1516 terms.
  1517 
  1518 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  1519 may no longer carry premises.  User-level specifications are
  1520 transformed accordingly by Thm.add_axiom/add_def.
  1521 
  1522 
  1523 *** System ***
  1524 
  1525 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  1526 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  1527 proof terms are enabled unconditionally in the new HOL-Proofs image.
  1528 
  1529 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  1530 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  1531 respectively.
  1532 
  1533 * Old lib/scripts/polyml-platform is superseded by the
  1534 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  1535 variant, even on a 64 bit machine.  The following example setting
  1536 prefers 64 bit if available:
  1537 
  1538   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  1539 
  1540 * The preliminary Isabelle/jEdit application demonstrates the emerging
  1541 Isabelle/Scala layer for advanced prover interaction and integration.
  1542 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  1543 component.
  1544 
  1545 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  1546 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  1547 similar to the default assignment of the document preparation system
  1548 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  1549 provides some operations for direct access to the font without asking
  1550 the user for manual installation.
  1551 
  1552 
  1553 
  1554 New in Isabelle2009-1 (December 2009)
  1555 -------------------------------------
  1556 
  1557 *** General ***
  1558 
  1559 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  1560 one backslash should be used, even in ML sources.
  1561 
  1562 
  1563 *** Pure ***
  1564 
  1565 * Locale interpretation propagates mixins along the locale hierarchy.
  1566 The currently only available mixins are the equations used to map
  1567 local definitions to terms of the target domain of an interpretation.
  1568 
  1569 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  1570 loc" to print all interpretations of locale "loc" in the theory.
  1571 Interpretations in proofs are not shown.
  1572 
  1573 * Thoroughly revised locales tutorial.  New section on conditional
  1574 interpretation.
  1575 
  1576 * On instantiation of classes, remaining undefined class parameters
  1577 are formally declared.  INCOMPATIBILITY.
  1578 
  1579 
  1580 *** Document preparation ***
  1581 
  1582 * New generalized style concept for printing terms: @{foo (style) ...}
  1583 instead of @{foo_style style ...}  (old form is still retained for
  1584 backward compatibility).  Styles can be also applied for
  1585 antiquotations prop, term_type and typeof.
  1586 
  1587 
  1588 *** HOL ***
  1589 
  1590 * New proof method "smt" for a combination of first-order logic with
  1591 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  1592 fixed-size bitvectors; there is also basic support for higher-order
  1593 features (esp. lambda abstractions).  It is an incomplete decision
  1594 procedure based on external SMT solvers using the oracle mechanism;
  1595 for the SMT solver Z3, this method is proof-producing.  Certificates
  1596 are provided to avoid calling the external solvers solely for
  1597 re-checking proofs.  Due to a remote SMT service there is no need for
  1598 installing SMT solvers locally.  See src/HOL/SMT.
  1599 
  1600 * New commands to load and prove verification conditions generated by
  1601 the Boogie program verifier or derived systems (e.g. the Verifying C
  1602 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1603 
  1604 * New counterexample generator tool 'nitpick' based on the Kodkod
  1605 relational model finder.  See src/HOL/Tools/Nitpick and
  1606 src/HOL/Nitpick_Examples.
  1607 
  1608 * New commands 'code_pred' and 'values' to invoke the predicate
  1609 compiler and to enumerate values of inductive predicates.
  1610 
  1611 * A tabled implementation of the reflexive transitive closure.
  1612 
  1613 * New implementation of quickcheck uses generic code generator;
  1614 default generators are provided for all suitable HOL types, records
  1615 and datatypes.  Old quickcheck can be re-activated importing theory
  1616 Library/SML_Quickcheck.
  1617 
  1618 * New testing tool Mirabelle for automated proof tools.  Applies
  1619 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1620 every proof step in a theory.  To be used in batch mode via the
  1621 "mirabelle" utility.
  1622 
  1623 * New proof method "sos" (sum of squares) for nonlinear real
  1624 arithmetic (originally due to John Harison). It requires theory
  1625 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1626 works well in practice on quantifier-free real arithmetic with +, -,
  1627 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1628 inequalities between polynomials.  It makes use of external
  1629 semidefinite programming solvers.  Method "sos" generates a
  1630 certificate that can be pasted into the proof thus avoiding the need
  1631 to call an external tool every time the proof is checked.  See
  1632 src/HOL/Library/Sum_Of_Squares.
  1633 
  1634 * New method "linarith" invokes existing linear arithmetic decision
  1635 procedure only.
  1636 
  1637 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1638 
  1639 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1640 Causes full type information to be output to the ATPs.  This slows
  1641 ATPs down considerably but eliminates a source of unsound "proofs"
  1642 that fail later.
  1643 
  1644 * New method "metisFT": A version of metis that uses full type
  1645 information in order to avoid failures of proof reconstruction.
  1646 
  1647 * New evaluator "approximate" approximates an real valued term using
  1648 the same method as the approximation method.
  1649 
  1650 * Method "approximate" now supports arithmetic expressions as
  1651 boundaries of intervals and implements interval splitting and Taylor
  1652 series expansion.
  1653 
  1654 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1655 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1656 
  1657 * New theory SupInf of the supremum and infimum operators for sets of
  1658 reals.
  1659 
  1660 * New theory Probability, which contains a development of measure
  1661 theory, eventually leading to Lebesgue integration and probability.
  1662 
  1663 * Extended Multivariate Analysis to include derivation and Brouwer's
  1664 fixpoint theorem.
  1665 
  1666 * Reorganization of number theory, INCOMPATIBILITY:
  1667   - new number theory development for nat and int, in theories Divides
  1668     and GCD as well as in new session Number_Theory
  1669   - some constants and facts now suffixed with _nat and _int
  1670     accordingly
  1671   - former session NumberTheory now named Old_Number_Theory, including
  1672     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1673   - moved theory Pocklington from src/HOL/Library to
  1674     src/HOL/Old_Number_Theory
  1675 
  1676 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1677 lcm of finite and infinite sets. It is shown that they form a complete
  1678 lattice.
  1679 
  1680 * Class semiring_div requires superclass no_zero_divisors and proof of
  1681 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1682 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1683 generalized to class semiring_div, subsuming former theorems
  1684 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1685 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1686 INCOMPATIBILITY.
  1687 
  1688 * Refinements to lattice classes and sets:
  1689   - less default intro/elim rules in locale variant, more default
  1690     intro/elim rules in class variant: more uniformity
  1691   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1692     le_inf_iff
  1693   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1694     sup_aci)
  1695   - renamed ACI to inf_sup_aci
  1696   - new class "boolean_algebra"
  1697   - class "complete_lattice" moved to separate theory
  1698     "Complete_Lattice"; corresponding constants (and abbreviations)
  1699     renamed and with authentic syntax:
  1700     Set.Inf ~>    Complete_Lattice.Inf
  1701     Set.Sup ~>    Complete_Lattice.Sup
  1702     Set.INFI ~>   Complete_Lattice.INFI
  1703     Set.SUPR ~>   Complete_Lattice.SUPR
  1704     Set.Inter ~>  Complete_Lattice.Inter
  1705     Set.Union ~>  Complete_Lattice.Union
  1706     Set.INTER ~>  Complete_Lattice.INTER
  1707     Set.UNION ~>  Complete_Lattice.UNION
  1708   - authentic syntax for
  1709     Set.Pow
  1710     Set.image
  1711   - mere abbreviations:
  1712     Set.empty               (for bot)
  1713     Set.UNIV                (for top)
  1714     Set.inter               (for inf, formerly Set.Int)
  1715     Set.union               (for sup, formerly Set.Un)
  1716     Complete_Lattice.Inter  (for Inf)
  1717     Complete_Lattice.Union  (for Sup)
  1718     Complete_Lattice.INTER  (for INFI)
  1719     Complete_Lattice.UNION  (for SUPR)
  1720   - object-logic definitions as far as appropriate
  1721 
  1722 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1723 Un_subset_iff are explicitly deleted as default simp rules; then also
  1724 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1725 deleted to achieve the desired effect.
  1726 
  1727 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1728 rules by default any longer; the same applies to min_max.inf_absorb1
  1729 etc.  INCOMPATIBILITY.
  1730 
  1731 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1732 pred_set_conv by default.  INCOMPATIBILITY.
  1733 
  1734 * Power operations on relations and functions are now one dedicated
  1735 constant "compow" with infix syntax "^^".  Power operation on
  1736 multiplicative monoids retains syntax "^" and is now defined generic
  1737 in class power.  INCOMPATIBILITY.
  1738 
  1739 * Relation composition "R O S" now has a more standard argument order:
  1740 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1741 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1742 break, since the O_assoc rule was not rewritten like this.  Fix using
  1743 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1744 
  1745 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1746 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1747 INCOMPATIBILITY.
  1748 
  1749 * Most rules produced by inductive and datatype package have mandatory
  1750 prefixes.  INCOMPATIBILITY.
  1751 
  1752 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1753 the attribute of the same name.  Each of the theorems in the list
  1754 DERIV_intros assumes composition with an additional function and
  1755 matches a variable to the derivative, which has to be solved by the
  1756 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1757 of most elementary terms.  Former Maclauren.DERIV_tac and
  1758 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1759 INCOMPATIBILITY.
  1760 
  1761 * Code generator attributes follow the usual underscore convention:
  1762     code_unfold     replaces    code unfold
  1763     code_post       replaces    code post
  1764     etc.
  1765   INCOMPATIBILITY.
  1766 
  1767 * Renamed methods:
  1768     sizechange -> size_change
  1769     induct_scheme -> induction_schema
  1770   INCOMPATIBILITY.
  1771 
  1772 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1773 INCOMPATIBILITY, use "undefined" directly.
  1774 
  1775 * Renamed theorems:
  1776     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1777     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1778     Suc_plus1 -> Suc_eq_plus1
  1779     *anti_sym -> *antisym*
  1780     vector_less_eq_def -> vector_le_def
  1781   INCOMPATIBILITY.
  1782 
  1783 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1784 INCOMPATIBILITY.
  1785 
  1786 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1787 INCOMPATIBILITY.
  1788 
  1789 
  1790 *** HOLCF ***
  1791 
  1792 * Theory Representable defines a class "rep" of domains that are
  1793 representable (via an ep-pair) in the universal domain type "udom".
  1794 Instances are provided for all type constructors defined in HOLCF.
  1795 
  1796 * The 'new_domain' command is a purely definitional version of the
  1797 domain package, for representable domains.  Syntax is identical to the
  1798 old domain package.  The 'new_domain' package also supports indirect
  1799 recursion using previously-defined type constructors.  See
  1800 src/HOLCF/ex/New_Domain.thy for examples.
  1801 
  1802 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1803 on the left-hand side of an equation, and then performs
  1804 simplification.  Rewriting is done using rules declared with the
  1805 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1806 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1807 
  1808 * The pattern-match compiler in 'fixrec' can now handle constructors
  1809 with HOL function types.  Pattern-match combinators for the Pair
  1810 constructor are pre-configured.
  1811 
  1812 * The 'fixrec' package now produces better fixed-point induction rules
  1813 for mutually-recursive definitions:  Induction rules have conclusions
  1814 of the form "P foo bar" instead of "P <foo, bar>".
  1815 
  1816 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1817 been renamed to "below".  The name "below" now replaces "less" in many
  1818 theorem names.  (Legacy theorem names using "less" are still supported
  1819 as well.)
  1820 
  1821 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1822 patterns can be used to generate strictness rules, or to make
  1823 functions more strict (much like the bang-patterns supported by the
  1824 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1825 examples.
  1826 
  1827 
  1828 *** ML ***
  1829 
  1830 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1831 errors and run-time exceptions, including detailed source positions.
  1832 
  1833 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1834 identified entries, with some additional information such as source
  1835 position, logical grouping etc.
  1836 
  1837 * Theory and context data is now introduced by the simplified and
  1838 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1839 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1840 copy operation) is still available for some time.
  1841 
  1842 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1843 provides a high-level programming interface to synchronized state
  1844 variables with atomic update.  This works via pure function
  1845 application within a critical section -- its runtime should be as
  1846 short as possible; beware of deadlocks if critical code is nested,
  1847 either directly or indirectly via other synchronized variables!
  1848 
  1849 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1850 wraps raw ML references, explicitly indicating their non-thread-safe
  1851 behaviour.  The Isar toplevel keeps this structure open, to
  1852 accommodate Proof General as well as quick and dirty interactive
  1853 experiments with references.
  1854 
  1855 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1856 parallel tactical reasoning.
  1857 
  1858 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1859 are similar to SUBPROOF, but are slightly more flexible: only the
  1860 specified parts of the subgoal are imported into the context, and the
  1861 body tactic may introduce new subgoals and schematic variables.
  1862 
  1863 * Old tactical METAHYPS, which does not observe the proof context, has
  1864 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1865 or Subgoal.FOCUS etc.
  1866 
  1867 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  1868 functors have their own ML name space there is no point to mark them
  1869 separately.)  Minor INCOMPATIBILITY.
  1870 
  1871 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  1872 
  1873 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  1874 INCOMPATIBILITY.
  1875 
  1876 * Operations of structure Skip_Proof no longer require quick_and_dirty
  1877 mode, which avoids critical setmp.
  1878 
  1879 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  1880 combinators for "args".  INCOMPATIBILITY, need to use simplified
  1881 Attrib/Method.setup introduced in Isabelle2009.
  1882 
  1883 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  1884 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  1885 last resort.  INCOMPATIBILITY.
  1886 
  1887 * Display.pretty_thm now requires a proper context (cf. former
  1888 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  1889 or even Display.pretty_thm_without_context as last resort.
  1890 INCOMPATIBILITY.
  1891 
  1892 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  1893 Syntax.pretty_typ/term directly, preferably with proper context
  1894 instead of global theory.
  1895 
  1896 
  1897 *** System ***
  1898 
  1899 * Further fine tuning of parallel proof checking, scales up to 8 cores
  1900 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  1901 usedir option -q.
  1902 
  1903 * Support for additional "Isabelle components" via etc/components, see
  1904 also the system manual.
  1905 
  1906 * The isabelle makeall tool now operates on all components with
  1907 IsaMakefile, not just hardwired "logics".
  1908 
  1909 * Removed "compress" option from isabelle-process and isabelle usedir;
  1910 this is always enabled.
  1911 
  1912 * Discontinued support for Poly/ML 4.x versions.
  1913 
  1914 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  1915 on a given logic image.  This requires the lighttpd webserver and is
  1916 currently supported on Linux only.
  1917 
  1918 
  1919 
  1920 New in Isabelle2009 (April 2009)
  1921 --------------------------------
  1922 
  1923 *** General ***
  1924 
  1925 * Simplified main Isabelle executables, with less surprises on
  1926 case-insensitive file-systems (such as Mac OS).
  1927 
  1928   - The main Isabelle tool wrapper is now called "isabelle" instead of
  1929     "isatool."
  1930 
  1931   - The former "isabelle" alias for "isabelle-process" has been
  1932     removed (should rarely occur to regular users).
  1933 
  1934   - The former "isabelle-interface" and its alias "Isabelle" have been
  1935     removed (interfaces are now regular Isabelle tools).
  1936 
  1937 Within scripts and make files, the Isabelle environment variables
  1938 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  1939 respectively.  (The latter are still available as legacy feature.)
  1940 
  1941 The old isabelle-interface wrapper could react in confusing ways if
  1942 the interface was uninstalled or changed otherwise.  Individual
  1943 interface tool configuration is now more explicit, see also the
  1944 Isabelle system manual.  In particular, Proof General is now available
  1945 via "isabelle emacs".
  1946 
  1947 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  1948 purge installed copies of Isabelle executables and re-run "isabelle
  1949 install -p ...", or use symlinks.
  1950 
  1951 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  1952 old ~/isabelle, which was slightly non-standard and apt to cause
  1953 surprises on case-insensitive file-systems (such as Mac OS).
  1954 
  1955 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  1956 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  1957 care is required when using older releases of Isabelle.  Note that
  1958 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  1959 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  1960 
  1961 * Proofs of fully specified statements are run in parallel on
  1962 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  1963 a regular 4-core machine, if the initial heap space is made reasonably
  1964 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  1965 
  1966 * The main reference manuals ("isar-ref", "implementation", and
  1967 "system") have been updated and extended.  Formally checked references
  1968 as hyperlinks are now available uniformly.
  1969 
  1970 
  1971 *** Pure ***
  1972 
  1973 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  1974 respects.  The most important changes are listed below.  See the
  1975 Tutorial on Locales ("locales" manual) for details.
  1976 
  1977 - In locale expressions, instantiation replaces renaming.  Parameters
  1978 must be declared in a for clause.  To aid compatibility with previous
  1979 parameter inheritance, in locale declarations, parameters that are not
  1980 'touched' (instantiation position "_" or omitted) are implicitly added
  1981 with their syntax at the beginning of the for clause.
  1982 
  1983 - Syntax from abbreviations and definitions in locales is available in
  1984 locale expressions and context elements.  The latter is particularly
  1985 useful in locale declarations.
  1986 
  1987 - More flexible mechanisms to qualify names generated by locale
  1988 expressions.  Qualifiers (prefixes) may be specified in locale
  1989 expressions, and can be marked as mandatory (syntax: "name!:") or
  1990 optional (syntax "name?:").  The default depends for plain "name:"
  1991 depends on the situation where a locale expression is used: in
  1992 commands 'locale' and 'sublocale' prefixes are optional, in
  1993 'interpretation' and 'interpret' prefixes are mandatory.  The old
  1994 implicit qualifiers derived from the parameter names of a locale are
  1995 no longer generated.
  1996 
  1997 - Command "sublocale l < e" replaces "interpretation l < e".  The
  1998 instantiation clause in "interpretation" and "interpret" (square
  1999 brackets) is no longer available.  Use locale expressions.
  2000 
  2001 - When converting proof scripts, mandatory qualifiers in
  2002 'interpretation' and 'interpret' should be retained by default, even
  2003 if this is an INCOMPATIBILITY compared to former behavior.  In the
  2004 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  2005 in locale expressions range over a single locale instance only.
  2006 
  2007 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  2008 In existing theorem specifications replace the includes element by the
  2009 respective context elements of the included locale, omitting those
  2010 that are already present in the theorem specification.  Multiple
  2011 assume elements of a locale should be replaced by a single one
  2012 involving the locale predicate.  In the proof body, declarations (most
  2013 notably theorems) may be regained by interpreting the respective
  2014 locales in the proof context as required (command "interpret").
  2015 
  2016 If using "includes" in replacement of a target solely because the
  2017 parameter types in the theorem are not as general as in the target,
  2018 consider declaring a new locale with additional type constraints on
  2019 the parameters (context element "constrains").
  2020 
  2021 - Discontinued "locale (open)".  INCOMPATIBILITY.
  2022 
  2023 - Locale interpretation commands no longer attempt to simplify goal.
  2024 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  2025 methods intro_locales and unfold_locales to clarify.
  2026 
  2027 - Locale interpretation commands no longer accept interpretation
  2028 attributes.  INCOMPATIBILITY.
  2029 
  2030 * Class declaration: so-called "base sort" must not be given in import
  2031 list any longer, but is inferred from the specification.  Particularly
  2032 in HOL, write
  2033 
  2034     class foo = ...
  2035 
  2036 instead of
  2037 
  2038     class foo = type + ...
  2039 
  2040 * Class target: global versions of theorems stemming do not carry a
  2041 parameter prefix any longer.  INCOMPATIBILITY.
  2042 
  2043 * Class 'instance' command no longer accepts attached definitions.
  2044 INCOMPATIBILITY, use proper 'instantiation' target instead.
  2045 
  2046 * Recovered hiding of consts, which was accidentally broken in
  2047 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  2048 makes c inaccessible; consider using ``hide (open) const c'' instead.
  2049 
  2050 * Slightly more coherent Pure syntax, with updated documentation in
  2051 isar-ref manual.  Removed locales meta_term_syntax and
  2052 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  2053 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  2054 directly in regular applications.
  2055 
  2056 * There is a new syntactic category "float_const" for signed decimal
  2057 fractions (e.g. 123.45 or -123.45).
  2058 
  2059 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  2060 interface with 'setup' command instead.
  2061 
  2062 * Command 'local_setup' is similar to 'setup', but operates on a local
  2063 theory context.
  2064 
  2065 * The 'axiomatization' command now only works within a global theory
  2066 context.  INCOMPATIBILITY.
  2067 
  2068 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  2069 hypotheses.  Sorts required in the course of reasoning need to be
  2070 covered by the constraints in the initial statement, completed by the
  2071 type instance information of the background theory.  Non-trivial sort
  2072 hypotheses, which rarely occur in practice, may be specified via
  2073 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  2074 
  2075   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  2076 
  2077 The result contains an implicit sort hypotheses as before --
  2078 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  2079 normalization.
  2080 
  2081 * Generalized Isar history, with support for linear undo, direct state
  2082 addressing etc.
  2083 
  2084 * Changed defaults for unify configuration options:
  2085 
  2086   unify_trace_bound = 50 (formerly 25)
  2087   unify_search_bound = 60 (formerly 30)
  2088 
  2089 * Different bookkeeping for code equations (INCOMPATIBILITY):
  2090 
  2091   a) On theory merge, the last set of code equations for a particular
  2092      constant is taken (in accordance with the policy applied by other
  2093      parts of the code generator framework).
  2094 
  2095   b) Code equations stemming from explicit declarations (e.g. code
  2096      attribute) gain priority over default code equations stemming
  2097      from definition, primrec, fun etc.
  2098 
  2099 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  2100 
  2101 * Unified theorem tables for both code generators.  Thus [code
  2102 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  2103 
  2104 * Command 'find_consts' searches for constants based on type and name
  2105 patterns, e.g.
  2106 
  2107     find_consts "_ => bool"
  2108 
  2109 By default, matching is against subtypes, but it may be restricted to
  2110 the whole type.  Searching by name is possible.  Multiple queries are
  2111 conjunctive and queries may be negated by prefixing them with a
  2112 hyphen:
  2113 
  2114     find_consts strict: "_ => bool" name: "Int" -"int => int"
  2115 
  2116 * New 'find_theorems' criterion "solves" matches theorems that
  2117 directly solve the current goal (modulo higher-order unification).
  2118 
  2119 * Auto solve feature for main theorem statements: whenever a new goal
  2120 is stated, "find_theorems solves" is called; any theorems that could
  2121 solve the lemma directly are listed as part of the goal state.
  2122 Cf. associated options in Proof General Isabelle settings menu,
  2123 enabled by default, with reasonable timeout for pathological cases of
  2124 higher-order unification.
  2125 
  2126 
  2127 *** Document preparation ***
  2128 
  2129 * Antiquotation @{lemma} now imitates a regular terminal proof,
  2130 demanding keyword 'by' and supporting the full method expression
  2131 syntax just like the Isar command 'by'.
  2132 
  2133 
  2134 *** HOL ***
  2135 
  2136 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  2137 points Main and Complex_Main remain as before.
  2138 
  2139 * Logic image HOL-Plain provides a minimal HOL with the most important
  2140 tools available (inductive, datatype, primrec, ...).  This facilitates
  2141 experimentation and tool development.  Note that user applications
  2142 (and library theories) should never refer to anything below theory
  2143 Main, as before.
  2144 
  2145 * Logic image HOL-Main stops at theory Main, and thus facilitates
  2146 experimentation due to shorter build times.
  2147 
  2148 * Logic image HOL-NSA contains theories of nonstandard analysis which
  2149 were previously part of former HOL-Complex.  Entry point Hyperreal
  2150 remains valid, but theories formerly using Complex_Main should now use
  2151 new entry point Hypercomplex.
  2152 
  2153 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  2154 Posix processes.  Avoids potentially expensive forking of the ML
  2155 process.  New thread-based implementation also works on non-Unix
  2156 platforms (Cygwin).  Provers are no longer hardwired, but defined
  2157 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  2158 commands are covered in the isar-ref manual.
  2159 
  2160 * Wrapper scripts for remote SystemOnTPTP service allows to use
  2161 sledgehammer without local ATP installation (Vampire etc.). Other
  2162 provers may be included via suitable ML wrappers, see also
  2163 src/HOL/ATP_Linkup.thy.
  2164 
  2165 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  2166 menu.
  2167 
  2168 * The metis method no longer fails because the theorem is too trivial
  2169 (contains the empty clause).
  2170 
  2171 * The metis method now fails in the usual manner, rather than raising
  2172 an exception, if it determines that it cannot prove the theorem.
  2173 
  2174 * Method "coherent" implements a prover for coherent logic (see also
  2175 src/Tools/coherent.ML).
  2176 
  2177 * Constants "undefined" and "default" replace "arbitrary".  Usually
  2178 "undefined" is the right choice to replace "arbitrary", though
  2179 logically there is no difference.  INCOMPATIBILITY.
  2180 
  2181 * Command "value" now integrates different evaluation mechanisms.  The
  2182 result of the first successful evaluation mechanism is printed.  In
  2183 square brackets a particular named evaluation mechanisms may be
  2184 specified (currently, [SML], [code] or [nbe]).  See further
  2185 src/HOL/ex/Eval_Examples.thy.
  2186 
  2187 * Normalization by evaluation now allows non-leftlinear equations.
  2188 Declare with attribute [code nbe].
  2189 
  2190 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  2191 as the structured Isar versions "cases" and "induct", cf. the
  2192 corresponding "cases" and "induct" attributes.  Mutual induction rules
  2193 are now presented as a list of individual projections
  2194 (e.g. foo_bar.inducts for types foo and bar); the old format with
  2195 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  2196 rare situations a different rule is selected --- notably nested tuple
  2197 elimination instead of former prod.exhaust: use explicit (case_tac t
  2198 rule: prod.exhaust) here.
  2199 
  2200 * Attributes "cases", "induct", "coinduct" support "del" option.
  2201 
  2202 * Removed fact "case_split_thm", which duplicates "case_split".
  2203 
  2204 * The option datatype has been moved to a new theory Option.  Renamed
  2205 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  2206 
  2207 * New predicate "strict_mono" classifies strict functions on partial
  2208 orders.  With strict functions on linear orders, reasoning about
  2209 (in)equalities is facilitated by theorems "strict_mono_eq",
  2210 "strict_mono_less_eq" and "strict_mono_less".
  2211 
  2212 * Some set operations are now proper qualified constants with
  2213 authentic syntax.  INCOMPATIBILITY:
  2214 
  2215     op Int ~>   Set.Int
  2216     op Un ~>    Set.Un
  2217     INTER ~>    Set.INTER
  2218     UNION ~>    Set.UNION
  2219     Inter ~>    Set.Inter
  2220     Union ~>    Set.Union
  2221     {} ~>       Set.empty
  2222     UNIV ~>     Set.UNIV
  2223 
  2224 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  2225 theory Set.
  2226 
  2227 * Auxiliary class "itself" has disappeared -- classes without any
  2228 parameter are treated as expected by the 'class' command.
  2229 
  2230 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  2231 
  2232 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  2233 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  2234 
  2235 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  2236 method "approximation".  It proves formulas on real values by using
  2237 interval arithmetic.  In the formulas are also the transcendental
  2238 functions sin, cos, tan, atan, ln, exp and the constant pi are
  2239 allowed. For examples see
  2240 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  2241 
  2242 * Theory "Reflection" now resides in HOL/Library.
  2243 
  2244 * Entry point to Word library now simply named "Word".
  2245 INCOMPATIBILITY.
  2246 
  2247 * Made source layout more coherent with logical distribution
  2248 structure:
  2249 
  2250     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  2251     src/HOL/Library/Code_Message.thy ~> src/HOL/
  2252     src/HOL/Library/GCD.thy ~> src/HOL/
  2253     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  2254     src/HOL/Library/Parity.thy ~> src/HOL/
  2255     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  2256     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  2257     src/HOL/Real/Lubs.thy ~> src/HOL/
  2258     src/HOL/Real/PReal.thy ~> src/HOL/
  2259     src/HOL/Real/Rational.thy ~> src/HOL/
  2260     src/HOL/Real/RComplete.thy ~> src/HOL/
  2261     src/HOL/Real/RealDef.thy ~> src/HOL/
  2262     src/HOL/Real/RealPow.thy ~> src/HOL/
  2263     src/HOL/Real/Real.thy ~> src/HOL/
  2264     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  2265     src/HOL/Complex/Complex.thy ~> src/HOL/
  2266     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  2267     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  2268     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  2269     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  2270     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  2271     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  2272     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  2273     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  2274     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  2275     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  2276     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  2277     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  2278     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  2279     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  2280     src/HOL/Real/Float ~> src/HOL/Library/
  2281     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  2282     src/HOL/Real/RealVector.thy ~> src/HOL/
  2283 
  2284     src/HOL/arith_data.ML ~> src/HOL/Tools
  2285     src/HOL/hologic.ML ~> src/HOL/Tools
  2286     src/HOL/simpdata.ML ~> src/HOL/Tools
  2287     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  2288     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  2289     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  2290     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  2291     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  2292     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  2293     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  2294 
  2295     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  2296     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  2297     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  2298     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  2299     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  2300     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  2301 
  2302 * If methods "eval" and "evaluation" encounter a structured proof
  2303 state with !!/==>, only the conclusion is evaluated to True (if
  2304 possible), avoiding strange error messages.
  2305 
  2306 * Method "sizechange" automates termination proofs using (a
  2307 modification of) the size-change principle.  Requires SAT solver.  See
  2308 src/HOL/ex/Termination.thy for examples.
  2309 
  2310 * Simplifier: simproc for let expressions now unfolds if bound
  2311 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  2312 
  2313 * Method "arith": Linear arithmetic now ignores all inequalities when
  2314 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  2315 
  2316 * New attribute "arith" for facts that should always be used
  2317 automatically by arithmetic. It is intended to be used locally in
  2318 proofs, e.g.
  2319 
  2320   assumes [arith]: "x > 0"
  2321 
  2322 Global usage is discouraged because of possible performance impact.
  2323 
  2324 * New classes "top" and "bot" with corresponding operations "top" and
  2325 "bot" in theory Orderings; instantiation of class "complete_lattice"
  2326 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  2327 
  2328 * Changed definition lemma "less_fun_def" in order to provide an
  2329 instance for preorders on functions; use lemma "less_le" instead.
  2330 INCOMPATIBILITY.
  2331 
  2332 * Theory Orderings: class "wellorder" moved here, with explicit
  2333 induction rule "less_induct" as assumption.  For instantiation of
  2334 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  2335 INCOMPATIBILITY.
  2336 
  2337 * Theory Orderings: added class "preorder" as superclass of "order".
  2338 INCOMPATIBILITY: Instantiation proofs for order, linorder
  2339 etc. slightly changed.  Some theorems named order_class.* now named
  2340 preorder_class.*.
  2341 
  2342 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  2343 "diag" to "Id_on".
  2344 
  2345 * Theory Finite_Set: added a new fold combinator of type
  2346 
  2347   ('a => 'b => 'b) => 'b => 'a set => 'b
  2348 
  2349 Occasionally this is more convenient than the old fold combinator
  2350 which is now defined in terms of the new one and renamed to
  2351 fold_image.
  2352 
  2353 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  2354 and "ring_simps" have been replaced by "algebra_simps" (which can be
  2355 extended with further lemmas!).  At the moment both still exist but
  2356 the former will disappear at some point.
  2357 
  2358 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  2359 class recpower.  Type-specific simp rules for various recpower types
  2360 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  2361 
  2362 rat_power_0    -> power_0
  2363 rat_power_Suc  -> power_Suc
  2364 realpow_0      -> power_0
  2365 realpow_Suc    -> power_Suc
  2366 complexpow_0   -> power_0
  2367 complexpow_Suc -> power_Suc
  2368 power_poly_0   -> power_0
  2369 power_poly_Suc -> power_Suc
  2370 
  2371 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  2372 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  2373 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  2374 of lemmas from Divides has been generalized from nat to class
  2375 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  2376 renames resulting from duplicate elimination:
  2377 
  2378     dvd_def_mod ~>          dvd_eq_mod_eq_0
  2379     zero_dvd_iff ~>         dvd_0_left_iff
  2380     dvd_0 ~>                dvd_0_right
  2381     DIVISION_BY_ZERO_DIV ~> div_by_0
  2382     DIVISION_BY_ZERO_MOD ~> mod_by_0
  2383     mult_div ~>             div_mult_self2_is_id
  2384     mult_mod ~>             mod_mult_self2_is_0
  2385 
  2386 * Theory IntDiv: removed many lemmas that are instances of class-based
  2387 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  2388 rename old lemmas as follows:
  2389 
  2390 dvd_diff               -> nat_dvd_diff
  2391 dvd_zminus_iff         -> dvd_minus_iff
  2392 mod_add1_eq            -> mod_add_eq
  2393 mod_mult1_eq           -> mod_mult_right_eq
  2394 mod_mult1_eq'          -> mod_mult_left_eq
  2395 mod_mult_distrib_mod   -> mod_mult_eq
  2396 nat_mod_add_left_eq    -> mod_add_left_eq
  2397 nat_mod_add_right_eq   -> mod_add_right_eq
  2398 nat_mod_div_trivial    -> mod_div_trivial
  2399 nat_mod_mod_trivial    -> mod_mod_trivial
  2400 zdiv_zadd_self1        -> div_add_self1
  2401 zdiv_zadd_self2        -> div_add_self2
  2402 zdiv_zmult_self1       -> div_mult_self2_is_id
  2403 zdiv_zmult_self2       -> div_mult_self1_is_id
  2404 zdvd_triv_left         -> dvd_triv_left
  2405 zdvd_triv_right        -> dvd_triv_right
  2406 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  2407 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  2408 zmod_zadd_left_eq      -> mod_add_left_eq
  2409 zmod_zadd_right_eq     -> mod_add_right_eq
  2410 zmod_zadd_self1        -> mod_add_self1
  2411 zmod_zadd_self2        -> mod_add_self2
  2412 zmod_zadd1_eq          -> mod_add_eq
  2413 zmod_zdiff1_eq         -> mod_diff_eq
  2414 zmod_zdvd_zmod         -> mod_mod_cancel
  2415 zmod_zmod_cancel       -> mod_mod_cancel
  2416 zmod_zmult_self1       -> mod_mult_self2_is_0
  2417 zmod_zmult_self2       -> mod_mult_self1_is_0
  2418 zmod_1                 -> mod_by_1
  2419 zdiv_1                 -> div_by_1
  2420 zdvd_abs1              -> abs_dvd_iff
  2421 zdvd_abs2              -> dvd_abs_iff
  2422 zdvd_refl              -> dvd_refl
  2423 zdvd_trans             -> dvd_trans
  2424 zdvd_zadd              -> dvd_add
  2425 zdvd_zdiff             -> dvd_diff
  2426 zdvd_zminus_iff        -> dvd_minus_iff
  2427 zdvd_zminus2_iff       -> minus_dvd_iff
  2428 zdvd_zmultD            -> dvd_mult_right
  2429 zdvd_zmultD2           -> dvd_mult_left
  2430 zdvd_zmult_mono        -> mult_dvd_mono
  2431 zdvd_0_right           -> dvd_0_right
  2432 zdvd_0_left            -> dvd_0_left_iff
  2433 zdvd_1_left            -> one_dvd
  2434 zminus_dvd_iff         -> minus_dvd_iff
  2435 
  2436 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  2437 
  2438 * The real numbers offer decimal input syntax: 12.34 is translated
  2439 into 1234/10^2. This translation is not reversed upon output.
  2440 
  2441 * Theory Library/Polynomial defines an abstract type 'a poly of
  2442 univariate polynomials with coefficients of type 'a.  In addition to
  2443 the standard ring operations, it also supports div and mod.  Code
  2444 generation is also supported, using list-style constructors.
  2445 
  2446 * Theory Library/Inner_Product defines a class of real_inner for real
  2447 inner product spaces, with an overloaded operation inner :: 'a => 'a
  2448 => real.  Class real_inner is a subclass of real_normed_vector from
  2449 theory RealVector.
  2450 
  2451 * Theory Library/Product_Vector provides instances for the product
  2452 type 'a * 'b of several classes from RealVector and Inner_Product.
  2453 Definitions of addition, subtraction, scalar multiplication, norms,
  2454 and inner products are included.
  2455 
  2456 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  2457 addition to the field operations, numerals and case syntax are also
  2458 supported.
  2459 
  2460 * Theory Library/Diagonalize provides constructive version of Cantor's
  2461 first diagonalization argument.
  2462 
  2463 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  2464 zlcm (for int); carried together from various gcd/lcm developements in
  2465 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  2466 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  2467 may recover tupled syntax as follows:
  2468 
  2469     hide (open) const gcd
  2470     abbreviation gcd where
  2471       "gcd == (%(a, b). GCD.gcd a b)"
  2472     notation (output)
  2473       GCD.gcd ("gcd '(_, _')")
  2474 
  2475 The same works for lcm, zgcd, zlcm.
  2476 
  2477 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  2478 instantiations for algebraic structures.  Removed some duplicate
  2479 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  2480 
  2481 * ML antiquotation @{code} takes a constant as argument and generates
  2482 corresponding code in background and inserts name of the corresponding
  2483 resulting ML value/function/datatype constructor binding in place.
  2484 All occurrences of @{code} with a single ML block are generated
  2485 simultaneously.  Provides a generic and safe interface for
  2486 instrumentalizing code generation.  See
  2487 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  2488 In future you ought to refrain from ad-hoc compiling generated SML
  2489 code on the ML toplevel.  Note that (for technical reasons) @{code}
  2490 cannot refer to constants for which user-defined serializations are
  2491 set.  Refer to the corresponding ML counterpart directly in that
  2492 cases.
  2493 
  2494 * Command 'rep_datatype': instead of theorem names the command now
  2495 takes a list of terms denoting the constructors of the type to be
  2496 represented as datatype.  The characteristic theorems have to be
  2497 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  2498 have disappeared in favour of existing ones:
  2499 
  2500     unit_induct                 ~> unit.induct
  2501     prod_induct                 ~> prod.induct
  2502     sum_induct                  ~> sum.induct
  2503     Suc_Suc_eq                  ~> nat.inject
  2504     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  2505 
  2506 
  2507 *** HOL-Algebra ***
  2508 
  2509 * New locales for orders and lattices where the equivalence relation
  2510 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  2511 locales use a record structure with field eq for the equivalence.
  2512 
  2513 * New theory of factorial domains.
  2514 
  2515 * Units_l_inv and Units_r_inv are now simp rules by default.
  2516 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  2517 and/or r_inv will now also require deletion of these lemmas.
  2518 
  2519 * Renamed the following theorems, INCOMPATIBILITY:
  2520 
  2521 UpperD ~> Upper_memD
  2522 LowerD ~> Lower_memD
  2523 least_carrier ~> least_closed
  2524 greatest_carrier ~> greatest_closed
  2525 greatest_Lower_above ~> greatest_Lower_below
  2526 one_zero ~> carrier_one_zero
  2527 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  2528 
  2529 
  2530 *** HOL-Nominal ***
  2531 
  2532 * Nominal datatypes can now contain type-variables.
  2533 
  2534 * Commands 'nominal_inductive' and 'equivariance' work with local
  2535 theory targets.
  2536 
  2537 * Nominal primrec can now works with local theory targets and its
  2538 specification syntax now conforms to the general format as seen in
  2539 'inductive' etc.
  2540 
  2541 * Method "perm_simp" honours the standard simplifier attributes
  2542 (no_asm), (no_asm_use) etc.
  2543 
  2544 * The new predicate #* is defined like freshness, except that on the
  2545 left hand side can be a set or list of atoms.
  2546 
  2547 * Experimental command 'nominal_inductive2' derives strong induction
  2548 principles for inductive definitions.  In contrast to
  2549 'nominal_inductive', which can only deal with a fixed number of
  2550 binders, it can deal with arbitrary expressions standing for sets of
  2551 atoms to be avoided.  The only inductive definition we have at the
  2552 moment that needs this generalisation is the typing rule for Lets in
  2553 the algorithm W:
  2554 
  2555  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  2556  -----------------------------------------------------------------
  2557          Gamma |- Let x be t1 in t2 : T2
  2558 
  2559 In this rule one wants to avoid all the binders that are introduced by
  2560 "close Gamma T1".  We are looking for other examples where this
  2561 feature might be useful.  Please let us know.
  2562 
  2563 
  2564 *** HOLCF ***
  2565 
  2566 * Reimplemented the simplification procedure for proving continuity
  2567 subgoals.  The new simproc is extensible; users can declare additional
  2568 continuity introduction rules with the attribute [cont2cont].
  2569 
  2570 * The continuity simproc now uses a different introduction rule for
  2571 solving continuity subgoals on terms with lambda abstractions.  In
  2572 some rare cases the new simproc may fail to solve subgoals that the
  2573 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  2574 Potential INCOMPATIBILITY.
  2575 
  2576 * Command 'fixrec': specification syntax now conforms to the general
  2577 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  2578 examples.  INCOMPATIBILITY.
  2579 
  2580 
  2581 *** ZF ***
  2582 
  2583 * Proof of Zorn's Lemma for partial orders.
  2584 
  2585 
  2586 *** ML ***
  2587 
  2588 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  2589 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  2590 depends on multithreading, so timouts will not work before Poly/ML
  2591 5.2.1!
  2592 
  2593 * High-level support for concurrent ML programming, see
  2594 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  2595 particularly convenient to organize independent functional
  2596 computations.  The concept of "synchronized variables" provides a
  2597 higher-order interface for components with shared state, avoiding the
  2598 delicate details of mutexes and condition variables.  (Requires
  2599 Poly/ML 5.2.1 or later.)
  2600 
  2601 * ML bindings produced via Isar commands are stored within the Isar
  2602 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2603 become thread-safe and work with undo as expected (concerning
  2604 top-level bindings, not side-effects on global references).
  2605 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2606 compiler at runtime; really global bindings need to be given outside a
  2607 theory.  (Requires Poly/ML 5.2 or later.)
  2608 
  2609 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2610 context.  Top-level ML bindings are stored within the proof context in
  2611 a purely sequential fashion, disregarding the nested proof structure.
  2612 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2613 proof.  (Requires Poly/ML 5.2 or later.)
  2614 
  2615 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2616 and Method.setup, as well as Isar commands 'attribute_setup' and
  2617 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2618 existing code accordingly, or use plain 'setup' together with old
  2619 Method.add_method.
  2620 
  2621 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2622 to 'a -> thm, while results are always tagged with an authentic oracle
  2623 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2624 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2625 accordingly.  Note that extra performance may be gained by producing
  2626 the cterm carefully, avoiding slow Thm.cterm_of.
  2627 
  2628 * Simplified interface for defining document antiquotations via
  2629 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2630 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2631 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2632 examples.
  2633 
  2634 * More systematic treatment of long names, abstract name bindings, and
  2635 name space operations.  Basic operations on qualified names have been
  2636 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2637 Long_Name.append.  Old type bstring has been mostly replaced by
  2638 abstract type binding (see structure Binding), which supports precise
  2639 qualification by packages and local theory targets, as well as proper
  2640 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2641 bstring values into Binding.name, or better pass through abstract
  2642 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2643 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2644 
  2645 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2646 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2647 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2648 
  2649 * Disposed old type and term read functions (Sign.read_def_typ,
  2650 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2651 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2652 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2653 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2654 resort for legacy applications.
  2655 
  2656 * Disposed old declarations, tactics, tactic combinators that refer to
  2657 the simpset or claset of an implicit theory (such as Addsimps,
  2658 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2659 embedded ML text, or local_simpset_of with a proper context passed as
  2660 explicit runtime argument.
  2661 
  2662 * Rules and tactics that read instantiations (read_instantiate,
  2663 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2664 context, which is required for parsing and type-checking.  Moreover,
  2665 the variables are specified as plain indexnames, not string encodings
  2666 thereof.  INCOMPATIBILITY.
  2667 
  2668 * Generic Toplevel.add_hook interface allows to analyze the result of
  2669 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2670 for theorem dependency output of transactions resulting in a new
  2671 theory state.
  2672 
  2673 * ML antiquotations: block-structured compilation context indicated by
  2674 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2675 
  2676   @{binding name}                         - basic name binding
  2677   @{let ?pat = term}                      - term abbreviation (HO matching)
  2678   @{note name = fact}                     - fact abbreviation
  2679   @{thm fact}                             - singleton fact (with attributes)
  2680   @{thms fact}                            - general fact (with attributes)
  2681   @{lemma prop by method}                 - singleton goal
  2682   @{lemma prop by meth1 meth2}            - singleton goal
  2683   @{lemma prop1 ... propN by method}      - general goal
  2684   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2685   @{lemma (open) ...}                     - open derivation
  2686 
  2687 
  2688 *** System ***
  2689 
  2690 * The Isabelle "emacs" tool provides a specific interface to invoke
  2691 Proof General / Emacs, with more explicit failure if that is not
  2692 installed (the old isabelle-interface script silently falls back on
  2693 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2694 installation location of the Proof General distribution.
  2695 
  2696 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2697 the Isabelle process into a JVM/Scala application.  See
  2698 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2699 process wrapper has been discontinued.)
  2700 
  2701 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2702 
  2703 * Various status messages (with exact source position information) are
  2704 emitted, if proper markup print mode is enabled.  This allows
  2705 user-interface components to provide detailed feedback on internal
  2706 prover operations.
  2707 
  2708 
  2709 
  2710 New in Isabelle2008 (June 2008)
  2711 -------------------------------
  2712 
  2713 *** General ***
  2714 
  2715 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2716 and updated, with formally checked references as hyperlinks.
  2717 
  2718 * Theory loader: use_thy (and similar operations) no longer set the
  2719 implicit ML context, which was occasionally hard to predict and in
  2720 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2721 provides a proper context already.
  2722 
  2723 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2724 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2725 'use' within a theory file will do the job.
  2726 
  2727 * Name space merge now observes canonical order, i.e. the second space
  2728 is inserted into the first one, while existing entries in the first
  2729 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2730 swap theory imports.
  2731 
  2732 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2733 INCOMPATIBILITY in identifier syntax etc.
  2734 
  2735 * Outer syntax: string tokens no longer admit escaped white space,
  2736 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2737 white space without escapes.
  2738 
  2739 * Outer syntax: string tokens may contain arbitrary character codes
  2740 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2741 "foo_bar".
  2742 
  2743 
  2744 *** Pure ***
  2745 
  2746 * Context-dependent token translations.  Default setup reverts locally
  2747 fixed variables, and adds hilite markup for undeclared frees.
  2748 
  2749 * Unused theorems can be found using the new command 'unused_thms'.
  2750 There are three ways of invoking it:
  2751 
  2752 (1) unused_thms
  2753      Only finds unused theorems in the current theory.
  2754 
  2755 (2) unused_thms thy_1 ... thy_n -
  2756      Finds unused theorems in the current theory and all of its ancestors,
  2757      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2758 
  2759 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2760      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2761      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2762      their ancestors.
  2763 
  2764 In order to increase the readability of the list produced by
  2765 unused_thms, theorems that have been created by a particular instance
  2766 of a theory command such as 'inductive' or 'function' are considered
  2767 to belong to the same "group", meaning that if at least one theorem in
  2768 this group is used, the other theorems in the same group are no longer
  2769 reported as unused.  Moreover, if all theorems in the group are
  2770 unused, only one theorem in the group is displayed.
  2771 
  2772 Note that proof objects have to be switched on in order for
  2773 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2774 usually the case when using Proof General with the default settings).
  2775 
  2776 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2777 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2778 duplicate fact bindings, or even accidental fact duplications.  Note
  2779 that tools may maintain dynamically scoped facts systematically, using
  2780 PureThy.add_thms_dynamic.
  2781 
  2782 * Command 'hide' now allows to hide from "fact" name space as well.
  2783 
  2784 * Eliminated destructive theorem database, simpset, claset, and
  2785 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2786 update of theories within ML code.
  2787 
  2788 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2789 INCOMPATIBILITY, object-logics depending on former Pure require
  2790 additional setup PureThy.old_appl_syntax_setup; object-logics
  2791 depending on former CPure need to refer to Pure.
  2792 
  2793 * Commands 'use' and 'ML' are now purely functional, operating on
  2794 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2795 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2796 INCOMPATIBILITY.
  2797 
  2798 * Command 'setup': discontinued implicit version with ML reference.
  2799 
  2800 * Instantiation target allows for simultaneous specification of class
  2801 instance operations together with an instantiation proof.
  2802 Type-checking phase allows to refer to class operations uniformly.
  2803 See src/HOL/Complex/Complex.thy for an Isar example and
  2804 src/HOL/Library/Eval.thy for an ML example.
  2805 
  2806 * Indexing of literal facts: be more serious about including only
  2807 facts from the visible specification/proof context, but not the
  2808 background context (locale etc.).  Affects `prop` notation and method
  2809 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2810 situations.
  2811 
  2812 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2813 "(open)" option, which used to expose internal bound variables to the
  2814 proof text.
  2815 
  2816 * Isar statements: removed obsolete case "rule_context".
  2817 INCOMPATIBILITY, better use explicit fixes/assumes.
  2818 
  2819 * Locale proofs: default proof step now includes 'unfold_locales';
  2820 hence 'proof' without argument may be used to unfold locale
  2821 predicates.
  2822 
  2823 
  2824 *** Document preparation ***
  2825 
  2826 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2827 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2828 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2829 spot); renamed link color from "darkblue" to "linkcolor" (default
  2830 value unchanged, can be redefined via \definecolor); no longer sets
  2831 "a4paper" option (unnecessary or even intrusive).
  2832 
  2833 * Antiquotation @{lemma A method} proves proposition A by the given
  2834 method (either a method name or a method name plus (optional) method
  2835 arguments in parentheses) and prints A just like @{prop A}.
  2836 
  2837 
  2838 *** HOL ***
  2839 
  2840 * New primrec package.  Specification syntax conforms in style to
  2841 definition/function/....  No separate induction rule is provided.  The
  2842 "primrec" command distinguishes old-style and new-style specifications
  2843 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2844 When adjusting theories, beware: constants stemming from new-style
  2845 primrec specifications have authentic syntax.
  2846 
  2847 * Metis prover is now an order of magnitude faster, and also works
  2848 with multithreading.
  2849 
  2850 * Metis: the maximum number of clauses that can be produced from a
  2851 theorem is now given by the attribute max_clauses.  Theorems that
  2852 exceed this number are ignored, with a warning printed.
  2853 
  2854 * Sledgehammer no longer produces structured proofs by default. To
  2855 enable, declare [[sledgehammer_full = true]].  Attributes
  2856 reconstruction_modulus, reconstruction_sorts renamed
  2857 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2858 
  2859 * Method "induct_scheme" derives user-specified induction rules
  2860 from well-founded induction and completeness of patterns. This factors
  2861 out some operations that are done internally by the function package
  2862 and makes them available separately.  See
  2863 src/HOL/ex/Induction_Scheme.thy for examples.
  2864 
  2865 * More flexible generation of measure functions for termination
  2866 proofs: Measure functions can be declared by proving a rule of the
  2867 form "is_measure f" and giving it the [measure_function] attribute.
  2868 The "is_measure" predicate is logically meaningless (always true), and
  2869 just guides the heuristic.  To find suitable measure functions, the
  2870 termination prover sets up the goal "is_measure ?f" of the appropriate
  2871 type and generates all solutions by prolog-style backwards proof using
  2872 the declared rules.
  2873 
  2874 This setup also deals with rules like 
  2875 
  2876   "is_measure f ==> is_measure (list_size f)"
  2877 
  2878 which accommodates nested datatypes that recurse through lists.
  2879 Similar rules are predeclared for products and option types.
  2880 
  2881 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  2882 
  2883   INCOMPATIBILITIES:
  2884 
  2885   - Definitions of overloaded constants on sets have to be replaced by
  2886     definitions on => and bool.
  2887 
  2888   - Some definitions of overloaded operators on sets can now be proved
  2889     using the definitions of the operators on => and bool.  Therefore,
  2890     the following theorems have been renamed:
  2891 
  2892       subset_def   -> subset_eq
  2893       psubset_def  -> psubset_eq
  2894       set_diff_def -> set_diff_eq
  2895       Compl_def    -> Compl_eq
  2896       Sup_set_def  -> Sup_set_eq
  2897       Inf_set_def  -> Inf_set_eq
  2898       sup_set_def  -> sup_set_eq
  2899       inf_set_def  -> inf_set_eq
  2900 
  2901   - Due to the incompleteness of the HO unification algorithm, some
  2902     rules such as subst may require manual instantiation, if some of
  2903     the unknowns in the rule is a set.
  2904 
  2905   - Higher order unification and forward proofs:
  2906     The proof pattern
  2907 
  2908       have "P (S::'a set)" <...>
  2909       then have "EX S. P S" ..
  2910 
  2911     no longer works (due to the incompleteness of the HO unification
  2912     algorithm) and must be replaced by the pattern
  2913 
  2914       have "EX S. P S"
  2915       proof
  2916         show "P S" <...>
  2917       qed
  2918 
  2919   - Calculational reasoning with subst (or similar rules):
  2920     The proof pattern
  2921 
  2922       have "P (S::'a set)" <...>
  2923       also have "S = T" <...>
  2924       finally have "P T" .
  2925 
  2926     no longer works (for similar reasons as the previous example) and
  2927     must be replaced by something like
  2928 
  2929       have "P (S::'a set)" <...>
  2930       moreover have "S = T" <...>
  2931       ultimately have "P T" by simp
  2932 
  2933   - Tactics or packages written in ML code:
  2934     Code performing pattern matching on types via
  2935 
  2936       Type ("set", [T]) => ...
  2937 
  2938     must be rewritten. Moreover, functions like strip_type or
  2939     binder_types no longer return the right value when applied to a
  2940     type of the form
  2941 
  2942       T1 => ... => Tn => U => bool
  2943 
  2944     rather than
  2945 
  2946       T1 => ... => Tn => U set
  2947 
  2948 * Merged theories Wellfounded_Recursion, Accessible_Part and
  2949 Wellfounded_Relations to theory Wellfounded.
  2950 
  2951 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  2952 
  2953 * Class finite no longer treats UNIV as class parameter.  Use class
  2954 enum from theory Library/Enum instead to achieve a similar effect.
  2955 INCOMPATIBILITY.
  2956 
  2957 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  2958 and "Cons".  INCOMPATIBILITY.
  2959 
  2960 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  2961 Potential INCOMPATIBILITY.
  2962 
  2963 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  2964 injective_fst_snd removed, use split_eta and prod_eqI instead.
  2965 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  2966 
  2967 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  2968 the same name in theory Orderings:
  2969 
  2970   less_trans
  2971   less_linear
  2972   le_imp_less_or_eq
  2973   le_less_trans
  2974   less_le_trans
  2975   less_not_sym
  2976   less_asym
  2977 
  2978 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  2979 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  2980 and different variable names.
  2981 
  2982 * Library/Option_ord.thy: Canonical order on option type.
  2983 
  2984 * Library/RBT.thy: Red-black trees, an efficient implementation of
  2985 finite maps.
  2986 
  2987 * Library/Countable.thy: Type class for countable types.
  2988 
  2989 * Theory Int: The representation of numerals has changed.  The infix
  2990 operator BIT and the bit datatype with constructors B0 and B1 have
  2991 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  2992 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  2993 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  2994 accordingly.
  2995 
  2996 * Theory Nat: definition of <= and < on natural numbers no longer
  2997 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  2998 le_def and less_def have disappeared.  Consider lemmas not_less
  2999 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  3000 
  3001 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  3002 (whose purpose mainly is for various fold_set functionals) have been
  3003 abandoned in favor of the existing algebraic classes
  3004 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  3005 lower_semilattice (resp. upper_semilattice) and linorder.
  3006 INCOMPATIBILITY.
  3007 
  3008 * Theory Transitive_Closure: induct and cases rules now declare proper
  3009 case_names ("base" and "step").  INCOMPATIBILITY.
  3010 
  3011 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  3012 lattices.  The form set-specific version is available as
  3013 Inductive.lfp_ordinal_induct_set.
  3014 
  3015 * Renamed theorems "power.simps" to "power_int.simps".
  3016 INCOMPATIBILITY.
  3017 
  3018 * Class semiring_div provides basic abstract properties of semirings
  3019 with division and modulo operations.  Subsumes former class dvd_mod.
  3020 
  3021 * Merged theories IntDef, Numeral and IntArith into unified theory
  3022 Int.  INCOMPATIBILITY.
  3023 
  3024 * Theory Library/Code_Index: type "index" now represents natural
  3025 numbers rather than integers.  INCOMPATIBILITY.
  3026 
  3027 * New class "uminus" with operation "uminus" (split of from class
  3028 "minus" which now only has operation "minus", binary).
  3029 INCOMPATIBILITY.
  3030 
  3031 * Constants "card", "internal_split", "option_map" now with authentic
  3032 syntax.  INCOMPATIBILITY.
  3033 
  3034 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  3035 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  3036 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  3037 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  3038 Sup_set_def, le_def, less_def, option_map_def now with object
  3039 equality.  INCOMPATIBILITY.
  3040 
  3041 * Records. Removed K_record, and replaced it by pure lambda term
  3042 %x. c. The simplifier setup is now more robust against eta expansion.
  3043 INCOMPATIBILITY: in cases explicitly referring to K_record.
  3044 
  3045 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  3046 
  3047 * Library/ListVector: new theory of arithmetic vector operations.
  3048 
  3049 * Library/Order_Relation: new theory of various orderings as sets of
  3050 pairs.  Defines preorders, partial orders, linear orders and
  3051 well-orders on sets and on types.
  3052 
  3053 
  3054 *** ZF ***
  3055 
  3056 * Renamed some theories to allow to loading both ZF and HOL in the
  3057 same session:
  3058 
  3059   Datatype  -> Datatype_ZF
  3060   Inductive -> Inductive_ZF
  3061   Int       -> Int_ZF
  3062   IntDiv    -> IntDiv_ZF
  3063   Nat       -> Nat_ZF
  3064   List      -> List_ZF
  3065   Main      -> Main_ZF
  3066 
  3067 INCOMPATIBILITY: ZF theories that import individual theories below
  3068 Main might need to be adapted.  Regular theory Main is still
  3069 available, as trivial extension of Main_ZF.
  3070 
  3071 
  3072 *** ML ***
  3073 
  3074 * ML within Isar: antiquotation @{const name} or @{const
  3075 name(typargs)} produces statically-checked Const term.
  3076 
  3077 * Functor NamedThmsFun: data is available to the user as dynamic fact
  3078 (of the same name).  Removed obsolete print command.
  3079 
  3080 * Removed obsolete "use_legacy_bindings" function.
  3081 
  3082 * The ``print mode'' is now a thread-local value derived from a global
  3083 template (the former print_mode reference), thus access becomes
  3084 non-critical.  The global print_mode reference is for session
  3085 management only; user-code should use print_mode_value,
  3086 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  3087 
  3088 * Functions system/system_out provide a robust way to invoke external
  3089 shell commands, with propagation of interrupts (requires Poly/ML
  3090 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  3091 
  3092 
  3093 *** System ***
  3094 
  3095 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  3096 in accordance with Proof General 3.7, which prefers GNU emacs.
  3097 
  3098 * isatool tty runs Isabelle process with plain tty interaction;
  3099 optional line editor may be specified via ISABELLE_LINE_EDITOR
  3100 setting, the default settings attempt to locate "ledit" and "rlwrap".
  3101 
  3102 * isatool browser now works with Cygwin as well, using general
  3103 "javapath" function defined in Isabelle process environment.
  3104 
  3105 * YXML notation provides a simple and efficient alternative to
  3106 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  3107 isatool yxml as described in the Isabelle system manual.
  3108 
  3109 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  3110 provides general wrapper for managing an Isabelle process in a robust
  3111 fashion, with ``cooked'' output from stdin/stderr.
  3112 
  3113 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  3114 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  3115 
  3116 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  3117 way of changing the user's settings is via
  3118 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  3119 script.
  3120 
  3121 * Multithreading.max_threads := 0 refers to the number of actual CPU
  3122 cores of the underlying machine, which is a good starting point for
  3123 optimal performance tuning.  The corresponding usedir option -M allows
  3124 "max" as an alias for "0".  WARNING: does not work on certain versions
  3125 of Mac OS (with Poly/ML 5.1).
  3126 
  3127 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  3128 adverse effect of Isabelle flooding interactive front-ends (notably
  3129 ProofGeneral / XEmacs).
  3130 
  3131 
  3132 
  3133 New in Isabelle2007 (November 2007)
  3134 -----------------------------------
  3135 
  3136 *** General ***
  3137 
  3138 * More uniform information about legacy features, notably a
  3139 warning/error of "Legacy feature: ...", depending on the state of the
  3140 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  3141 legacy features will disappear eventually.
  3142 
  3143 * Theory syntax: the header format ``theory A = B + C:'' has been
  3144 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  3145 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  3146 
  3147 * Theory syntax: the old non-Isar theory file format has been
  3148 discontinued altogether.  Note that ML proof scripts may still be used
  3149 with Isar theories; migration is usually quite simple with the ML
  3150 function use_legacy_bindings.  INCOMPATIBILITY.
  3151 
  3152 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  3153 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  3154 quotes.
  3155 
  3156 * Theory loader: be more serious about observing the static theory
  3157 header specifications (including optional directories), but not the
  3158 accidental file locations of previously successful loads.  The strict
  3159 update policy of former update_thy is now already performed by
  3160 use_thy, so the former has been removed; use_thys updates several
  3161 theories simultaneously, just as 'imports' within a theory header
  3162 specification, but without merging the results.  Potential
  3163 INCOMPATIBILITY: may need to refine theory headers and commands
  3164 ROOT.ML which depend on load order.
  3165 
  3166 * Theory loader: optional support for content-based file
  3167 identification, instead of the traditional scheme of full physical
  3168 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  3169 (cf. the system manual).  The new scheme allows to work with
  3170 non-finished theories in persistent session images, such that source
  3171 files may be moved later on without requiring reloads.
  3172 
  3173 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3174 file (with the same base name as the theory) are considered a legacy
  3175 feature, which will disappear eventually. Even now, the theory loader
  3176 no longer maintains dependencies on such files.
  3177 
  3178 * Syntax: the scope for resolving ambiguities via type-inference is
  3179 now limited to individual terms, instead of whole simultaneous
  3180 specifications as before. This greatly reduces the complexity of the
  3181 syntax module and improves flexibility by separating parsing and
  3182 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  3183 'fixes' etc.) are required in rare situations.
  3184 
  3185 * Syntax: constants introduced by new-style packages ('definition',
  3186 'abbreviation' etc.) are passed through the syntax module in
  3187 ``authentic mode''. This means that associated mixfix annotations
  3188 really stick to such constants, independently of potential name space
  3189 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  3190 trees are represented slightly differently, may need to adapt syntax
  3191 translations accordingly. Use CONST marker in 'translations' and
  3192 @{const_syntax} antiquotation in 'parse_translation' etc.
  3193 
  3194 * Legacy goal package: reduced interface to the bare minimum required
  3195 to keep existing proof scripts running.  Most other user-level
  3196 functions are now part of the OldGoals structure, which is *not* open
  3197 by default (consider isatool expandshort before open OldGoals).
  3198 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  3199 these tend to cause confusion about the actual goal (!) context being
  3200 used here, which is not necessarily the same as the_context().
  3201 
  3202 * Command 'find_theorems': supports "*" wild-card in "name:"
  3203 criterion; "with_dups" option.  Certain ProofGeneral versions might
  3204 support a specific search form (see ProofGeneral/CHANGES).
  3205 
  3206 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  3207 by default, which means that "prems" (and also "fixed variables") are
  3208 suppressed from proof state output.  Note that the ProofGeneral
  3209 settings mechanism allows to change and save options persistently, but
  3210 older versions of Isabelle will fail to start up if a negative prems
  3211 limit is imposed.
  3212 
  3213 * Local theory targets may be specified by non-nested blocks of
  3214 ``context/locale/class ... begin'' followed by ``end''.  The body may
  3215 contain definitions, theorems etc., including any derived mechanism
  3216 that has been implemented on top of these primitives.  This concept
  3217 generalizes the existing ``theorem (in ...)'' towards more versatility
  3218 and scalability.
  3219 
  3220 * Proof General interface: proper undo of final 'end' command;
  3221 discontinued Isabelle/classic mode (ML proof scripts).
  3222 
  3223 
  3224 *** Document preparation ***
  3225 
  3226 * Added antiquotation @{theory name} which prints the given name,
  3227 after checking that it refers to a valid ancestor theory in the
  3228 current context.
  3229 
  3230 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  3231 check the given source text as ML type/structure, printing verbatim.
  3232 
  3233 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  3234 "c args == rhs" given in the current context.  (Any number of
  3235 arguments may be given on the LHS.)
  3236 
  3237 
  3238 *** Pure ***
  3239 
  3240 * The 'class' package offers a combination of axclass and locale to
  3241 achieve Haskell-like type classes in Isabelle.  Definitions and
  3242 theorems within a class context produce both relative results (with
  3243 implicit parameters according to the locale context), and polymorphic
  3244 constants with qualified polymorphism (according to the class
  3245 context).  Within the body context of a 'class' target, a separate
  3246 syntax layer ("user space type system") takes care of converting
  3247 between global polymorphic consts and internal locale representation.
  3248 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  3249 "isatool doc classes" provides a tutorial.
  3250 
  3251 * Generic code generator framework allows to generate executable
  3252 code for ML and Haskell (including Isabelle classes).  A short usage
  3253 sketch:
  3254 
  3255     internal compilation:
  3256         export_code <list of constants (term syntax)> in SML
  3257     writing SML code to a file:
  3258         export_code <list of constants (term syntax)> in SML <filename>
  3259     writing OCaml code to a file:
  3260         export_code <list of constants (term syntax)> in OCaml <filename>
  3261     writing Haskell code to a bunch of files:
  3262         export_code <list of constants (term syntax)> in Haskell <filename>
  3263 
  3264     evaluating closed propositions to True/False using code generation:
  3265         method ``eval''
  3266 
  3267 Reasonable default setup of framework in HOL.
  3268 
  3269 Theorem attributs for selecting and transforming function equations theorems:
  3270 
  3271     [code fun]:        select a theorem as function equation for a specific constant
  3272     [code fun del]:    deselect a theorem as function equation for a specific constant
  3273     [code inline]:     select an equation theorem for unfolding (inlining) in place
  3274     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  3275 
  3276 User-defined serializations (target in {SML, OCaml, Haskell}):
  3277 
  3278     code_const <and-list of constants (term syntax)>
  3279       {(target) <and-list of const target syntax>}+
  3280 
  3281     code_type <and-list of type constructors>
  3282       {(target) <and-list of type target syntax>}+
  3283 
  3284     code_instance <and-list of instances>
  3285       {(target)}+
  3286         where instance ::= <type constructor> :: <class>
  3287 
  3288     code_class <and_list of classes>
  3289       {(target) <and-list of class target syntax>}+
  3290         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  3291 
  3292 code_instance and code_class only are effective to target Haskell.
  3293 
  3294 For example usage see src/HOL/ex/Codegenerator.thy and
  3295 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  3296 generation from Isabelle/HOL theories is available via "isatool doc
  3297 codegen".
  3298 
  3299 * Code generator: consts in 'consts_code' Isar commands are now
  3300 referred to by usual term syntax (including optional type
  3301 annotations).
  3302 
  3303 * Command 'no_translations' removes translation rules from theory
  3304 syntax.
  3305 
  3306 * Overloaded definitions are now actually checked for acyclic
  3307 dependencies.  The overloading scheme is slightly more general than
  3308 that of Haskell98, although Isabelle does not demand an exact
  3309 correspondence to type class and instance declarations.
  3310 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  3311 exotic versions of overloading -- at the discretion of the user!
  3312 
  3313 Polymorphic constants are represented via type arguments, i.e. the
  3314 instantiation that matches an instance against the most general
  3315 declaration given in the signature.  For example, with the declaration
  3316 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  3317 as c(nat).  Overloading is essentially simultaneous structural
  3318 recursion over such type arguments.  Incomplete specification patterns
  3319 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  3320 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  3321 Command 'print_theory' outputs the normalized system of recursive
  3322 equations, see section "definitions".
  3323 
  3324 * Configuration options are maintained within the theory or proof
  3325 context (with name and type bool/int/string), providing a very simple
  3326 interface to a poor-man's version of general context data.  Tools may
  3327 declare options in ML (e.g. using Attrib.config_int) and then refer to
  3328 these values using Config.get etc.  Users may change options via an
  3329 associated attribute of the same name.  This form of context
  3330 declaration works particularly well with commands 'declare' or
  3331 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  3332 very easy to avoid global references, which would not observe Isar
  3333 toplevel undo/redo and fail to work with multithreading.
  3334 
  3335 Various global ML references of Pure and HOL have been turned into
  3336 configuration options:
  3337 
  3338   Unify.search_bound		unify_search_bound
  3339   Unify.trace_bound		unify_trace_bound
  3340   Unify.trace_simp		unify_trace_simp
  3341   Unify.trace_types		unify_trace_types
  3342   Simplifier.simp_depth_limit	simp_depth_limit
  3343   Blast.depth_limit		blast_depth_limit
  3344   DatatypeProp.dtK		datatype_distinctness_limit
  3345   fast_arith_neq_limit  	fast_arith_neq_limit
  3346   fast_arith_split_limit	fast_arith_split_limit
  3347 
  3348 * Named collections of theorems may be easily installed as context
  3349 data using the functor NamedThmsFun (see also
  3350 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  3351 attributes; there is also a toplevel print command.  This facility is
  3352 just a common case of general context data, which is the preferred way
  3353 for anything more complex than just a list of facts in canonical
  3354 order.
  3355 
  3356 * Isar: command 'declaration' augments a local theory by generic
  3357 declaration functions written in ML.  This enables arbitrary content
  3358 being added to the context, depending on a morphism that tells the
  3359 difference of the original declaration context wrt. the application
  3360 context encountered later on.
  3361 
  3362 * Isar: proper interfaces for simplification procedures.  Command
  3363 'simproc_setup' declares named simprocs (with match patterns, and body
  3364 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  3365 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  3366 
  3367 * Isar: an extra pair of brackets around attribute declarations
  3368 abbreviates a theorem reference involving an internal dummy fact,
  3369 which will be ignored later --- only the effect of the attribute on
  3370 the background context will persist.  This form of in-place
  3371 declarations is particularly useful with commands like 'declare' and
  3372 'using', for example ``have A using [[simproc a]] by simp''.
  3373 
  3374 * Isar: method "assumption" (and implicit closing of subproofs) now
  3375 takes simple non-atomic goal assumptions into account: after applying
  3376 an assumption as a rule the resulting subgoals are solved by atomic
  3377 assumption steps.  This is particularly useful to finish 'obtain'
  3378 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  3379 without referring to the original premise "!!x. P x ==> thesis" in the
  3380 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  3381 more permissive.
  3382 
  3383 * Isar: implicit use of prems from the Isar proof context is
  3384 considered a legacy feature.  Common applications like ``have A .''
  3385 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  3386 referencing facts explicitly here improves readability and
  3387 maintainability of proof texts.
  3388 
  3389 * Isar: improper proof element 'guess' is like 'obtain', but derives
  3390 the obtained context from the course of reasoning!  For example:
  3391 
  3392   assume "EX x y. A x & B y"   -- "any previous fact"
  3393   then guess x and y by clarify
  3394 
  3395 This technique is potentially adventurous, depending on the facts and
  3396 proof tools being involved here.
  3397 
  3398 * Isar: known facts from the proof context may be specified as literal
  3399 propositions, using ASCII back-quote syntax.  This works wherever
  3400 named facts used to be allowed so far, in proof commands, proof
  3401 methods, attributes etc.  Literal facts are retrieved from the context
  3402 according to unification of type and term parameters.  For example,
  3403 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  3404 theorems in the current context, then these are valid literal facts:
  3405 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  3406 
  3407 There is also a proof method "fact" which does the same composition
  3408 for explicit goal states, e.g. the following proof texts coincide with
  3409 certain special cases of literal facts:
  3410 
  3411   have "A" by fact                 ==  note `A`
  3412   have "A ==> B" by fact           ==  note `A ==> B`
  3413   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  3414   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  3415 
  3416 * Isar: ":" (colon) is no longer a symbolic identifier character in
  3417 outer syntax.  Thus symbolic identifiers may be used without
  3418 additional white space in declarations like this: ``assume *: A''.
  3419 
  3420 * Isar: 'print_facts' prints all local facts of the current context,
  3421 both named and unnamed ones.
  3422 
  3423 * Isar: 'def' now admits simultaneous definitions, e.g.:
  3424 
  3425   def x == "t" and y == "u"
  3426 
  3427 * Isar: added command 'unfolding', which is structurally similar to
  3428 'using', but affects both the goal state and facts by unfolding given
  3429 rewrite rules.  Thus many occurrences of the 'unfold' method or
  3430 'unfolded' attribute may be replaced by first-class proof text.
  3431 
  3432 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  3433 and command 'unfolding' now all support object-level equalities
  3434 (potentially conditional).  The underlying notion of rewrite rule is
  3435 analogous to the 'rule_format' attribute, but *not* that of the
  3436 Simplifier (which is usually more generous).
  3437 
  3438 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  3439 premises of a theorem by n. Useful in conjunction with drule.
  3440 
  3441 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  3442 method expression within a sandbox consisting of the first N
  3443 sub-goals, which need to exist.  For example, ``simp_all [3]''
  3444 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  3445 simplifies all new goals that emerge from applying rule foo to the
  3446 originally first one.
  3447 
  3448 * Isar: schematic goals are no longer restricted to higher-order
  3449 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  3450 expected.
  3451 
  3452 * Isar: the conclusion of a long theorem statement is now either
  3453 'shows' (a simultaneous conjunction, as before), or 'obtains'
  3454 (essentially a disjunction of cases with local parameters and
  3455 assumptions).  The latter allows to express general elimination rules
  3456 adequately; in this notation common elimination rules look like this:
  3457 
  3458   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  3459     assumes "EX x. P x"
  3460     obtains x where "P x"
  3461 
  3462   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  3463     assumes "A & B"
  3464     obtains A and B
  3465 
  3466   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  3467     assumes "A | B"
  3468     obtains
  3469       A
  3470     | B
  3471 
  3472 The subsequent classical rules even refer to the formal "thesis"
  3473 explicitly:
  3474 
  3475   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  3476     obtains "~ thesis"
  3477 
  3478   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  3479     obtains "thesis ==> something"
  3480 
  3481 The actual proof of an 'obtains' statement is analogous to that of the
  3482 Isar proof element 'obtain', only that there may be several cases.
  3483 Optional case names may be specified in parentheses; these will be
  3484 available both in the present proof and as annotations in the
  3485 resulting rule, for later use with the 'cases' method (cf. attribute
  3486 case_names).
  3487 
  3488 * Isar: the assumptions of a long theorem statement are available as
  3489 "assms" fact in the proof context.  This is more appropriate than the
  3490 (historical) "prems", which refers to all assumptions of the current
  3491 context, including those from the target locale, proof body etc.
  3492 
  3493 * Isar: 'print_statement' prints theorems from the current theory or
  3494 proof context in long statement form, according to the syntax of a
  3495 top-level lemma.
  3496 
  3497 * Isar: 'obtain' takes an optional case name for the local context
  3498 introduction rule (default "that").
  3499 
  3500 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  3501 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  3502 to occur.
  3503 
  3504 * Pure: syntax "CONST name" produces a fully internalized constant
  3505 according to the current context.  This is particularly useful for
  3506 syntax translations that should refer to internal constant
  3507 representations independently of name spaces.
  3508 
  3509 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  3510 instead of "FOO ". This allows multiple binder declarations to coexist
  3511 in the same context.  INCOMPATIBILITY.
  3512 
  3513 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  3514 primitive that also works in a locale context (both for constants and
  3515 fixed variables). Type declaration and internal syntactic representation
  3516 of given constants retrieved from the context. Likewise, the
  3517 'no_notation' command allows to remove given syntax annotations from the
  3518 current context.
  3519 
  3520 * Isar/locales: new derived specification elements 'axiomatization',
  3521 'definition', 'abbreviation', which support type-inference, admit
  3522 object-level specifications (equality, equivalence).  See also the
  3523 isar-ref manual.  Examples:
  3524 
  3525   axiomatization
  3526     eq  (infix "===" 50) where
  3527     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  3528 
  3529   definition "f x y = x + y + 1"
  3530   definition g where "g x = f x x"
  3531 
  3532   abbreviation
  3533     neq  (infix "=!=" 50) where
  3534     "x =!= y == ~ (x === y)"
  3535 
  3536 These specifications may be also used in a locale context.  Then the
  3537 constants being introduced depend on certain fixed parameters, and the
  3538 constant name is qualified by the locale base name.  An internal
  3539 abbreviation takes care for convenient input and output, making the
  3540 parameters implicit and using the original short name.  See also
  3541 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  3542 entities from a monomorphic theory.
  3543 
  3544 Presently, abbreviations are only available 'in' a target locale, but
  3545 not inherited by general import expressions.  Also note that
  3546 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  3547 'translations' in common applications.  The "no_abbrevs" print mode
  3548 prevents folding of abbreviations in term output.
  3549 
  3550 Concrete syntax is attached to specified constants in internal form,
  3551 independently of name spaces.  The parse tree representation is
  3552 slightly different -- use 'notation' instead of raw 'syntax', and
  3553 'translations' with explicit "CONST" markup to accommodate this.
  3554 
  3555 * Pure/Isar: unified syntax for new-style specification mechanisms
  3556 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  3557 full type inference and dummy patterns ("_").  For example:
  3558 
  3559   definition "K x _ = x"
  3560 
  3561   inductive conj for A B
  3562   where "A ==> B ==> conj A B"
  3563 
  3564 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  3565 the current context.  Print mode "no_abbrevs" prevents inversion of
  3566 abbreviations on output.
  3567 
  3568 * Isar/locales: improved parameter handling: use of locales "var" and
  3569 "struct" no longer necessary; - parameter renamings are no longer
  3570 required to be injective.  For example, this allows to define
  3571 endomorphisms as locale endom = homom mult mult h.
  3572 
  3573 * Isar/locales: changed the way locales with predicates are defined.
  3574 Instead of accumulating the specification, the imported expression is
  3575 now an interpretation.  INCOMPATIBILITY: different normal form of
  3576 locale expressions.  In particular, in interpretations of locales with
  3577 predicates, goals repesenting already interpreted fragments are not
  3578 removed automatically.  Use methods `intro_locales' and
  3579 `unfold_locales'; see below.
  3580 
  3581 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  3582 provide backward reasoning on locales predicates.  The methods are
  3583 aware of interpretations and discharge corresponding goals.
  3584 `intro_locales' is less aggressive then `unfold_locales' and does not
  3585 unfold predicates to assumptions.
  3586 
  3587 * Isar/locales: the order in which locale fragments are accumulated
  3588 has changed.  This enables to override declarations from fragments due
  3589 to interpretations -- for example, unwanted simp rules.
  3590 
  3591 * Isar/locales: interpretation in theories and proof contexts has been
  3592 extended.  One may now specify (and prove) equations, which are
  3593 unfolded in interpreted theorems.  This is useful for replacing
  3594 defined concepts (constants depending on locale parameters) by
  3595 concepts already existing in the target context.  Example:
  3596 
  3597   interpretation partial_order ["op <= :: [int, int] => bool"]
  3598     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3599 
  3600 Typically, the constant `partial_order.less' is created by a
  3601 definition specification element in the context of locale
  3602 partial_order.
  3603 
  3604 * Method "induct": improved internal context management to support
  3605 local fixes and defines on-the-fly. Thus explicit meta-level
  3606 connectives !!  and ==> are rarely required anymore in inductive goals
  3607 (using object-logic connectives for this purpose has been long
  3608 obsolete anyway). Common proof patterns are explained in
  3609 src/HOL/Induct/Common_Patterns.thy, see also
  3610 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3611 examples.
  3612 
  3613 * Method "induct": improved handling of simultaneous goals. Instead of
  3614 introducing object-level conjunction, the statement is now split into
  3615 several conclusions, while the corresponding symbolic cases are nested
  3616 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3617 see src/HOL/Induct/Common_Patterns.thy, for example.
  3618 
  3619 * Method "induct": mutual induction rules are now specified as a list
  3620 of rule sharing the same induction cases. HOL packages usually provide
  3621 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3622 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3623 mutual induction rules differently, i.e. like this:
  3624 
  3625   (induct rule: foo_bar.inducts)
  3626   (induct set: foo bar)
  3627   (induct pred: foo bar)
  3628   (induct type: foo bar)
  3629 
  3630 The ML function ProjectRule.projections turns old-style rules into the
  3631 new format.
  3632 
  3633 * Method "coinduct": dual of induction, see
  3634 src/HOL/Library/Coinductive_List.thy for various examples.
  3635 
  3636 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3637 considered a legacy feature.
  3638 
  3639 * Attribute "symmetric" produces result with standardized schematic
  3640 variables (index 0).  Potential INCOMPATIBILITY.
  3641 
  3642 * Simplifier: by default the simplifier trace only shows top level
  3643 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3644 default. Thus there is less danger of being flooded by the trace. The
  3645 trace indicates where parts have been suppressed.
  3646   
  3647 * Provers/classical: removed obsolete classical version of elim_format
  3648 attribute; classical elim/dest rules are now treated uniformly when
  3649 manipulating the claset.
  3650 
  3651 * Provers/classical: stricter checks to ensure that supplied intro,
  3652 dest and elim rules are well-formed; dest and elim rules must have at
  3653 least one premise.
  3654 
  3655 * Provers/classical: attributes dest/elim/intro take an optional
  3656 weight argument for the rule (just as the Pure versions).  Weights are
  3657 ignored by automated tools, but determine the search order of single
  3658 rule steps.
  3659 
  3660 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3661 where the body does not mention the bound variable.  Note that dummy
  3662 patterns implicitly depend on their context of bounds, which makes
  3663 "{_. _}" match any set comprehension as expected.  Potential
  3664 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3665 constant "_idtdummy" in the binding position.
  3666 
  3667 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3668 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3669 for example "A -> B" => "Pi A (%_. B)".
  3670 
  3671 * Pure: 'class_deps' command visualizes the subclass relation, using
  3672 the graph browser tool.
  3673 
  3674 * Pure: 'print_theory' now suppresses certain internal declarations by
  3675 default; use '!' option for full details.
  3676 
  3677 
  3678 *** HOL ***
  3679 
  3680 * Method "metis" proves goals by applying the Metis general-purpose
  3681 resolution prover (see also http://gilith.com/software/metis/).
  3682 Examples are in the directory MetisExamples.  WARNING: the
  3683 Isabelle/HOL-Metis integration does not yet work properly with
  3684 multi-threading.
  3685   
  3686 * Command 'sledgehammer' invokes external automatic theorem provers as
  3687 background processes.  It generates calls to the "metis" method if
  3688 successful. These can be pasted into the proof.  Users do not have to
  3689 wait for the automatic provers to return.  WARNING: does not really
  3690 work with multi-threading.
  3691 
  3692 * New "auto_quickcheck" feature tests outermost goal statements for
  3693 potential counter-examples.  Controlled by ML references
  3694 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3695 5000 milliseconds).  Fails silently if statements is outside of
  3696 executable fragment, or any other codgenerator problem occurs.
  3697 
  3698 * New constant "undefined" with axiom "undefined x = undefined".
  3699 
  3700 * Added class "HOL.eq", allowing for code generation with polymorphic
  3701 equality.
  3702 
  3703 * Some renaming of class constants due to canonical name prefixing in
  3704 the new 'class' package:
  3705 
  3706     HOL.abs ~> HOL.abs_class.abs
  3707     HOL.divide ~> HOL.divide_class.divide
  3708     0 ~> HOL.zero_class.zero
  3709     1 ~> HOL.one_class.one
  3710     op + ~> HOL.plus_class.plus
  3711     op - ~> HOL.minus_class.minus
  3712     uminus ~> HOL.minus_class.uminus
  3713     op * ~> HOL.times_class.times
  3714     op < ~> HOL.ord_class.less
  3715     op <= > HOL.ord_class.less_eq
  3716     Nat.power ~> Power.power_class.power
  3717     Nat.size ~> Nat.size_class.size
  3718     Numeral.number_of ~> Numeral.number_class.number_of
  3719     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3720     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3721     Orderings.min ~> Orderings.ord_class.min
  3722     Orderings.max ~> Orderings.ord_class.max
  3723     Divides.op div ~> Divides.div_class.div
  3724     Divides.op mod ~> Divides.div_class.mod
  3725     Divides.op dvd ~> Divides.div_class.dvd
  3726 
  3727 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3728 
  3729 a) User-defined constants using any of the names "plus", "minus",
  3730 "times", "less" or "less_eq". The standard syntax translations for
  3731 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3732 names.
  3733 
  3734 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3735 INCOMPATIBILITY: use more specific names.
  3736 
  3737 c) Permutative equations (e.g. "a + b = b + a")
  3738 Since the change of names also changes the order of terms, permutative
  3739 rewrite rules may get applied in a different order. Experience shows
  3740 that this is rarely the case (only two adaptions in the whole Isabelle
  3741 distribution).  INCOMPATIBILITY: rewrite proofs
  3742 
  3743 d) ML code directly refering to constant names
  3744 This in general only affects hand-written proof tactics, simprocs and
  3745 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3746 Consider using @{const_name} antiquotation.
  3747 
  3748 * New class "default" with associated constant "default".
  3749 
  3750 * Function "sgn" is now overloaded and available on int, real, complex
  3751 (and other numeric types), using class "sgn".  Two possible defs of
  3752 sgn are given as equational assumptions in the classes sgn_if and
  3753 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3754 INCOMPATIBILITY.
  3755 
  3756 * Locale "partial_order" now unified with class "order" (cf. theory
  3757 Orderings), added parameter "less".  INCOMPATIBILITY.
  3758 
  3759 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3760 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3761 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3762 
  3763 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3764 changed order of proof goals in instance proofs.
  3765 
  3766 * The transitivity reasoner for partial and linear orders is set up
  3767 for classes "order" and "linorder".  Instances of the reasoner are available
  3768 in all contexts importing or interpreting the corresponding locales.
  3769 Method "order" invokes the reasoner separately; the reasoner
  3770 is also integrated with the Simplifier as a solver.  Diagnostic
  3771 command 'print_orders' shows the available instances of the reasoner
  3772 in the current context.
  3773 
  3774 * Localized monotonicity predicate in theory "Orderings"; integrated
  3775 lemmas max_of_mono and min_of_mono with this predicate.
  3776 INCOMPATIBILITY.
  3777 
  3778 * Formulation of theorem "dense" changed slightly due to integration
  3779 with new class dense_linear_order.
  3780 
  3781 * Uniform lattice theory development in HOL.
  3782 
  3783     constants "meet" and "join" now named "inf" and "sup"
  3784     constant "Meet" now named "Inf"
  3785 
  3786     classes "meet_semilorder" and "join_semilorder" now named
  3787       "lower_semilattice" and "upper_semilattice"
  3788     class "lorder" now named "lattice"
  3789     class "comp_lat" now named "complete_lattice"
  3790 
  3791     Instantiation of lattice classes allows explicit definitions
  3792     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3793 
  3794   INCOMPATIBILITY.  Theorem renames:
  3795 
  3796     meet_left_le            ~> inf_le1
  3797     meet_right_le           ~> inf_le2
  3798     join_left_le            ~> sup_ge1
  3799     join_right_le           ~> sup_ge2
  3800     meet_join_le            ~> inf_sup_ord
  3801     le_meetI                ~> le_infI
  3802     join_leI                ~> le_supI
  3803     le_meet                 ~> le_inf_iff
  3804     le_join                 ~> ge_sup_conv
  3805     meet_idempotent         ~> inf_idem
  3806     join_idempotent         ~> sup_idem
  3807     meet_comm               ~> inf_commute
  3808     join_comm               ~> sup_commute
  3809     meet_leI1               ~> le_infI1
  3810     meet_leI2               ~> le_infI2
  3811     le_joinI1               ~> le_supI1
  3812     le_joinI2               ~> le_supI2
  3813     meet_assoc              ~> inf_assoc
  3814     join_assoc              ~> sup_assoc
  3815     meet_left_comm          ~> inf_left_commute
  3816     meet_left_idempotent    ~> inf_left_idem
  3817     join_left_comm          ~> sup_left_commute
  3818     join_left_idempotent    ~> sup_left_idem
  3819     meet_aci                ~> inf_aci
  3820     join_aci                ~> sup_aci
  3821     le_def_meet             ~> le_iff_inf
  3822     le_def_join             ~> le_iff_sup
  3823     join_absorp2            ~> sup_absorb2
  3824     join_absorp1            ~> sup_absorb1
  3825     meet_absorp1            ~> inf_absorb1
  3826     meet_absorp2            ~> inf_absorb2
  3827     meet_join_absorp        ~> inf_sup_absorb
  3828     join_meet_absorp        ~> sup_inf_absorb
  3829     distrib_join_le         ~> distrib_sup_le
  3830     distrib_meet_le         ~> distrib_inf_le
  3831 
  3832     add_meet_distrib_left   ~> add_inf_distrib_left
  3833     add_join_distrib_left   ~> add_sup_distrib_left
  3834     is_join_neg_meet        ~> is_join_neg_inf
  3835     is_meet_neg_join        ~> is_meet_neg_sup
  3836     add_meet_distrib_right  ~> add_inf_distrib_right
  3837     add_join_distrib_right  ~> add_sup_distrib_right
  3838     add_meet_join_distribs  ~> add_sup_inf_distribs
  3839     join_eq_neg_meet        ~> sup_eq_neg_inf
  3840     meet_eq_neg_join        ~> inf_eq_neg_sup
  3841     add_eq_meet_join        ~> add_eq_inf_sup
  3842     meet_0_imp_0            ~> inf_0_imp_0
  3843     join_0_imp_0            ~> sup_0_imp_0
  3844     meet_0_eq_0             ~> inf_0_eq_0
  3845     join_0_eq_0             ~> sup_0_eq_0
  3846     neg_meet_eq_join        ~> neg_inf_eq_sup
  3847     neg_join_eq_meet        ~> neg_sup_eq_inf
  3848     join_eq_if              ~> sup_eq_if
  3849 
  3850     mono_meet               ~> mono_inf
  3851     mono_join               ~> mono_sup
  3852     meet_bool_eq            ~> inf_bool_eq
  3853     join_bool_eq            ~> sup_bool_eq
  3854     meet_fun_eq             ~> inf_fun_eq
  3855     join_fun_eq             ~> sup_fun_eq
  3856     meet_set_eq             ~> inf_set_eq
  3857     join_set_eq             ~> sup_set_eq
  3858     meet1_iff               ~> inf1_iff
  3859     meet2_iff               ~> inf2_iff
  3860     meet1I                  ~> inf1I
  3861     meet2I                  ~> inf2I
  3862     meet1D1                 ~> inf1D1
  3863     meet2D1                 ~> inf2D1
  3864     meet1D2                 ~> inf1D2
  3865     meet2D2                 ~> inf2D2
  3866     meet1E                  ~> inf1E
  3867     meet2E                  ~> inf2E
  3868     join1_iff               ~> sup1_iff
  3869     join2_iff               ~> sup2_iff
  3870     join1I1                 ~> sup1I1
  3871     join2I1                 ~> sup2I1
  3872     join1I1                 ~> sup1I1
  3873     join2I2                 ~> sup1I2
  3874     join1CI                 ~> sup1CI
  3875     join2CI                 ~> sup2CI
  3876     join1E                  ~> sup1E
  3877     join2E                  ~> sup2E
  3878 
  3879     is_meet_Meet            ~> is_meet_Inf
  3880     Meet_bool_def           ~> Inf_bool_def
  3881     Meet_fun_def            ~> Inf_fun_def
  3882     Meet_greatest           ~> Inf_greatest
  3883     Meet_lower              ~> Inf_lower
  3884     Meet_set_def            ~> Inf_set_def
  3885 
  3886     Sup_def                 ~> Sup_Inf
  3887     Sup_bool_eq             ~> Sup_bool_def
  3888     Sup_fun_eq              ~> Sup_fun_def
  3889     Sup_set_eq              ~> Sup_set_def
  3890 
  3891     listsp_meetI            ~> listsp_infI
  3892     listsp_meet_eq          ~> listsp_inf_eq
  3893 
  3894     meet_min                ~> inf_min
  3895     join_max                ~> sup_max
  3896 
  3897 * Added syntactic class "size"; overloaded constant "size" now has
  3898 type "'a::size ==> bool"
  3899 
  3900 * Internal reorganisation of `size' of datatypes: size theorems
  3901 "foo.size" are no longer subsumed by "foo.simps" (but are still
  3902 simplification rules by default!); theorems "prod.size" now named
  3903 "*.size".
  3904 
  3905 * Class "div" now inherits from class "times" rather than "type".
  3906 INCOMPATIBILITY.
  3907 
  3908 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  3909 Linorder etc.  have disappeared; operations defined in terms of
  3910 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  3911 
  3912 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  3913 
  3914 * HOL-Word: New extensive library and type for generic, fixed size
  3915 machine words, with arithemtic, bit-wise, shifting and rotating
  3916 operations, reflection into int, nat, and bool lists, automation for
  3917 linear arithmetic (by automatic reflection into nat or int), including
  3918 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  3919 arithmetic type classes, supporting automatic simplification of
  3920 numerals on all operations.
  3921 
  3922 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  3923 
  3924 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  3925 
  3926 * Code generator library theories:
  3927   - Code_Integer represents HOL integers by big integer literals in target
  3928     languages.
  3929   - Code_Char represents HOL characters by character literals in target
  3930     languages.
  3931   - Code_Char_chr like Code_Char, but also offers treatment of character
  3932     codes; includes Code_Integer.
  3933   - Executable_Set allows to generate code for finite sets using lists.
  3934   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  3935     denominator).
  3936   - Executable_Real implements a subset of real numbers, namly those
  3937     representable by rational numbers.
  3938   - Efficient_Nat implements natural numbers by integers, which in general will
  3939     result in higher efficency; pattern matching with 0/Suc is eliminated;
  3940     includes Code_Integer.
  3941   - Code_Index provides an additional datatype index which is mapped to
  3942     target-language built-in integers.
  3943   - Code_Message provides an additional datatype message_string which is isomorphic to
  3944     strings; messages are mapped to target-language strings.
  3945 
  3946 * New package for inductive predicates
  3947 
  3948   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  3949 
  3950     inductive
  3951       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3952       for z_1 :: U_1 and ... and z_n :: U_m
  3953     where
  3954       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3955     | ...
  3956 
  3957   with full support for type-inference, rather than
  3958 
  3959     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3960 
  3961     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3962     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3963 
  3964     inductive "s z_1 ... z_m"
  3965     intros
  3966       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3967       ...
  3968 
  3969   For backward compatibility, there is a wrapper allowing inductive
  3970   sets to be defined with the new package via
  3971 
  3972     inductive_set
  3973       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3974       for z_1 :: U_1 and ... and z_n :: U_m
  3975     where
  3976       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3977     | ...
  3978 
  3979   or
  3980 
  3981     inductive_set
  3982       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3983       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3984       for z_1 :: U_1 and ... and z_n :: U_m
  3985     where
  3986       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3987     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3988     | ...
  3989 
  3990   if the additional syntax "p ..." is required.
  3991 
  3992   Numerous examples can be found in the subdirectories src/HOL/Auth,
  3993   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  3994 
  3995   INCOMPATIBILITIES:
  3996 
  3997   - Since declaration and definition of inductive sets or predicates
  3998     is no longer separated, abbreviations involving the newly
  3999     introduced sets or predicates must be specified together with the
  4000     introduction rules after the 'where' keyword (see above), rather
  4001     than before the actual inductive definition.
  4002 
  4003   - The variables in induction and elimination rules are now
  4004     quantified in the order of their occurrence in the introduction
  4005     rules, rather than in alphabetical order. Since this may break
  4006     some proofs, these proofs either have to be repaired, e.g. by
  4007     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  4008     statements of the form
  4009 
  4010       case (rule_i a_i_1 ... a_i_{k_i})
  4011 
  4012     or the old order of quantification has to be restored by explicitly adding
  4013     meta-level quantifiers in the introduction rules, i.e.
  4014 
  4015       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  4016 
  4017   - The format of the elimination rules is now
  4018 
  4019       p z_1 ... z_m x_1 ... x_n ==>
  4020         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4021         ==> ... ==> P
  4022 
  4023     for predicates and
  4024 
  4025       (x_1, ..., x_n) : s z_1 ... z_m ==>
  4026         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4027         ==> ... ==> P
  4028 
  4029     for sets rather than
  4030 
  4031       x : s z_1 ... z_m ==>
  4032         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  4033         ==> ... ==> P
  4034 
  4035     This may require terms in goals to be expanded to n-tuples
  4036     (e.g. using case_tac or simplification with the split_paired_all
  4037     rule) before the above elimination rule is applicable.
  4038 
  4039   - The elimination or case analysis rules for (mutually) inductive
  4040     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  4041     list of rules "p_1_..._p_k.elims" is no longer available.
  4042 
  4043 * New package "function"/"fun" for general recursive functions,
  4044 supporting mutual and nested recursion, definitions in local contexts,
  4045 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  4046 for small examples, and the separate tutorial on the function
  4047 package. The old recdef "package" is still available as before, but
  4048 users are encouraged to use the new package.
  4049 
  4050 * Method "lexicographic_order" automatically synthesizes termination
  4051 relations as lexicographic combinations of size measures. 
  4052 
  4053 * Case-expressions allow arbitrary constructor-patterns (including
  4054 "_") and take their order into account, like in functional
  4055 programming.  Internally, this is translated into nested
  4056 case-expressions; missing cases are added and mapped to the predefined
  4057 constant "undefined". In complicated cases printing may no longer show
  4058 the original input but the internal form. Lambda-abstractions allow
  4059 the same form of pattern matching: "% pat1 => e1 | ..." is an
  4060 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  4061 variable.
  4062 
  4063 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  4064 is an abbreviation for "of_nat :: nat => int". The simplification
  4065 rules for "of_nat" have been changed to work like "int" did
  4066 previously.  Potential INCOMPATIBILITY:
  4067   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  4068   - of_nat_diff and of_nat_mult are no longer default simp rules
  4069 
  4070 * Method "algebra" solves polynomial equations over (semi)rings using
  4071 Groebner bases. The (semi)ring structure is defined by locales and the
  4072 tool setup depends on that generic context. Installing the method for
  4073 a specific type involves instantiating the locale and possibly adding
  4074 declarations for computation on the coefficients.  The method is
  4075 already instantiated for natural numbers and for the axiomatic class
  4076 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  4077 CALCULEMUS 2007 for the general principles underlying this
  4078 architecture of context-aware proof-tools.
  4079 
  4080 * Method "ferrack" implements quantifier elimination over
  4081 special-purpose dense linear orders using locales (analogous to
  4082 "algebra"). The method is already installed for class
  4083 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  4084 rat, etc.
  4085 
  4086 * Former constant "List.op @" now named "List.append".  Use ML
  4087 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  4088 circumvent possible incompatibilities when working on ML level.
  4089 
  4090 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  4091 
  4092 * New function listsum :: 'a list => 'a for arbitrary monoids.
  4093 Special syntax: "SUM x <- xs. f x" (and latex variants)
  4094 
  4095 * New syntax for Haskell-like list comprehension (input only), eg.
  4096 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  4097 
  4098 * The special syntax for function "filter" has changed from [x :
  4099 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  4100 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  4101 
  4102 * [a..b] is now defined for arbitrary linear orders.  It used to be
  4103 defined on nat only, as an abbreviation for [a..<Suc b]
  4104 INCOMPATIBILITY.
  4105 
  4106 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  4107 
  4108 * New functions "sorted" and "sort" in src/HOL/List.thy.
  4109 
  4110 * New lemma collection field_simps (an extension of ring_simps) for
  4111 manipulating (in)equations involving division. Multiplies with all
  4112 denominators that can be proved to be non-zero (in equations) or
  4113 positive/negative (in inequations).
  4114 
  4115 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  4116 have been improved and renamed to ring_simps, group_simps and
  4117 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  4118 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  4119 
  4120 * Theory Library/Commutative_Ring: switched from recdef to function
  4121 package; constants add, mul, pow now curried.  Infix syntax for
  4122 algebraic operations.
  4123 
  4124 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  4125 INCOMPATIBILITY.
  4126 
  4127 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  4128 INCOMPATIBILITY.
  4129 
  4130 * HOL/records: generalised field-update to take a function on the
  4131 field rather than the new value: r(|A := x|) is translated to A_update
  4132 (K x) r The K-combinator that is internally used is called K_record.
  4133 INCOMPATIBILITY: Usage of the plain update functions has to be
  4134 adapted.
  4135  
  4136 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  4137 * x = 0, which are required for a semiring.  Richer structures do not
  4138 inherit from semiring_0 anymore, because this property is a theorem
  4139 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  4140 there is more to prove, but this is mostly trivial.
  4141 
  4142 * Class "recpower" is generalized to arbitrary monoids, not just
  4143 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  4144 commutativity or semiring properties additionally.
  4145 
  4146 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  4147 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  4148 better use 'abbreviation'.
  4149 
  4150 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  4151 
  4152 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  4153 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  4154 significant changes for setting up numeral syntax for types:
  4155   - New constants Numeral.pred and Numeral.succ instead
  4156       of former Numeral.bin_pred and Numeral.bin_succ.
  4157   - Use integer operations instead of bin_add, bin_mult and so on.
  4158   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  4159   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  4160 
  4161 See src/HOL/Integ/IntArith.thy for an example setup.
  4162 
  4163 * Command 'normal_form' computes the normal form of a term that may
  4164 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  4165 produces ``[b, c, a]'' (without proof).  This command is suitable for
  4166 heavy-duty computations because the functions are compiled to ML
  4167 first.  Correspondingly, a method "normalization" is provided.  See
  4168 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  4169 
  4170 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  4171 25 like -->); output depends on the "iff" print_mode, the default is
  4172 "A = B" (with priority 50).
  4173 
  4174 * Relations less (<) and less_eq (<=) are also available on type bool.
  4175 Modified syntax to disallow nesting without explicit parentheses,
  4176 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  4177 INCOMPATIBILITY.
  4178 
  4179 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  4180 
  4181 * Relation composition operator "op O" now has precedence 75 and binds
  4182 stronger than union and intersection. INCOMPATIBILITY.
  4183 
  4184 * The old set interval syntax "{m..n(}" (and relatives) has been
  4185 removed.  Use "{m..<n}" (and relatives) instead.
  4186 
  4187 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  4188 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  4189 ``declare [[simproc del: neq]]''.
  4190 
  4191 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  4192 True/False.
  4193 
  4194 * Theorem Cons_eq_map_conv no longer declared as "simp".
  4195 
  4196 * Theorem setsum_mult renamed to setsum_right_distrib.
  4197 
  4198 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  4199 ``rule'' method.
  4200 
  4201 * Reimplemented methods "sat" and "satx", with several improvements:
  4202 goals no longer need to be stated as "<prems> ==> False", equivalences
  4203 (i.e. "=" on type bool) are handled, variable names of the form
  4204 "lit_<n>" are no longer reserved, significant speedup.
  4205 
  4206 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  4207 zChaff is still supported as well.
  4208 
  4209 * 'inductive' and 'datatype': provide projections of mutual rules,
  4210 bundled as foo_bar.inducts;
  4211 
  4212 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  4213 Library.
  4214 
  4215 * Library: moved theory Accessible_Part to main HOL.
  4216 
  4217 * Library: added theory Coinductive_List of potentially infinite lists
  4218 as greatest fixed-point.
  4219 
  4220 * Library: added theory AssocList which implements (finite) maps as
  4221 association lists.
  4222 
  4223 * Method "evaluation" solves goals (i.e. a boolean expression)
  4224 efficiently by compiling it to ML.  The goal is "proved" (via an
  4225 oracle) if it evaluates to True.
  4226 
  4227 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  4228 also when invoked by the simplifier.  This results in the Simplifier
  4229 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  4230 Configuration option fast_arith_split_limit=0 recovers the old
  4231 behavior.
  4232 
  4233 * Support for hex (0x20) and binary (0b1001) numerals.
  4234 
  4235 * New method: reify eqs (t), where eqs are equations for an
  4236 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  4237 parameter, computes a term s::'b and a list xs::'a list and proves the
  4238 theorem I xs s = t. This is also known as reification or quoting. The
  4239 resulting theorem is applied to the subgoal to substitute t with I xs
  4240 s.  If t is omitted, the subgoal itself is reified.
  4241 
  4242 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  4243 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  4244 where f is supposed to be a computable function (in the sense of code
  4245 generattion). The method uses reify to compute s and xs as above then
  4246 applies corr_thm and uses normalization by evaluation to "prove" f s =
  4247 r and finally gets the theorem t = r, which is again applied to the
  4248 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  4249 
  4250 * Reflection: Automatic reification now handels binding, an example is
  4251 available in src/HOL/ex/ReflectionEx.thy
  4252 
  4253 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  4254 command 'statespace' that is similar to 'record', but introduces an
  4255 abstract specification based on the locale infrastructure instead of
  4256 HOL types.  This leads to extra flexibility in composing state spaces,
  4257 in particular multiple inheritance and renaming of components.
  4258 
  4259 
  4260 *** HOL-Complex ***
  4261 
  4262 * Hyperreal: Functions root and sqrt are now defined on negative real
  4263 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  4264 Nonnegativity side conditions have been removed from many lemmas, so
  4265 that more subgoals may now be solved by simplification; potential
  4266 INCOMPATIBILITY.
  4267 
  4268 * Real: new type classes formalize real normed vector spaces and
  4269 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  4270 and norm :: 'a => real.
  4271 
  4272 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  4273 reals into other types. The overloaded constant Reals :: 'a set is now
  4274 defined as range of_real; potential INCOMPATIBILITY.
  4275 
  4276 * Real: proper support for ML code generation, including 'quickcheck'.
  4277 Reals are implemented as arbitrary precision rationals.
  4278 
  4279 * Hyperreal: Several constants that previously worked only for the
  4280 reals have been generalized, so they now work over arbitrary vector
  4281 spaces. Type annotations may need to be added in some cases; potential
  4282 INCOMPATIBILITY.
  4283 
  4284   Infinitesimal  :: ('a::real_normed_vector) star set
  4285   HFinite        :: ('a::real_normed_vector) star set
  4286   HInfinite      :: ('a::real_normed_vector) star set
  4287   approx         :: ('a::real_normed_vector) star => 'a star => bool
  4288   monad          :: ('a::real_normed_vector) star => 'a star set
  4289   galaxy         :: ('a::real_normed_vector) star => 'a star set
  4290   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  4291   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  4292   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  4293   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  4294   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  4295   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  4296   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  4297   sgn            :: 'a::real_normed_vector => 'a
  4298   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  4299 
  4300 * Complex: Some complex-specific constants are now abbreviations for
  4301 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  4302 hnorm.  Other constants have been entirely removed in favor of the
  4303 polymorphic versions (INCOMPATIBILITY):
  4304 
  4305   approx        <-- capprox
  4306   HFinite       <-- CFinite
  4307   HInfinite     <-- CInfinite
  4308   Infinitesimal <-- CInfinitesimal
  4309   monad         <-- cmonad
  4310   galaxy        <-- cgalaxy
  4311   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  4312   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  4313   (ns)deriv     <-- (ns)cderiv
  4314 
  4315 
  4316 *** HOL-Algebra ***
  4317 
  4318 * Formalisation of ideals and the quotient construction over rings.
  4319 
  4320 * Order and lattice theory no longer based on records.
  4321 INCOMPATIBILITY.
  4322 
  4323 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  4324 greatest_closed.  INCOMPATIBILITY.
  4325 
  4326 * Method algebra is now set up via an attribute.  For examples see
  4327 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  4328 of algebraic structures.
  4329 
  4330 * Renamed theory CRing to Ring.
  4331 
  4332 
  4333 *** HOL-Nominal ***
  4334 
  4335 * Substantial, yet incomplete support for nominal datatypes (binding
  4336 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  4337 src/HOL/Nominal/Examples.  Prospective users should consult
  4338 http://isabelle.in.tum.de/nominal/
  4339 
  4340 
  4341 *** ML ***
  4342 
  4343 * ML basics: just one true type int, which coincides with IntInf.int
  4344 (even on SML/NJ).
  4345 
  4346 * ML within Isar: antiquotations allow to embed statically-checked
  4347 formal entities in the source, referring to the context available at
  4348 compile-time.  For example:
  4349 
  4350 ML {* @{sort "{zero,one}"} *}
  4351 ML {* @{typ "'a => 'b"} *}
  4352 ML {* @{term "%x. x"} *}
  4353 ML {* @{prop "x == y"} *}
  4354 ML {* @{ctyp "'a => 'b"} *}
  4355 ML {* @{cterm "%x. x"} *}
  4356 ML {* @{cprop "x == y"} *}
  4357 ML {* @{thm asm_rl} *}
  4358 ML {* @{thms asm_rl} *}
  4359 ML {* @{type_name c} *}
  4360 ML {* @{type_syntax c} *}
  4361 ML {* @{const_name c} *}
  4362 ML {* @{const_syntax c} *}
  4363 ML {* @{context} *}
  4364 ML {* @{theory} *}
  4365 ML {* @{theory Pure} *}
  4366 ML {* @{theory_ref} *}
  4367 ML {* @{theory_ref Pure} *}
  4368 ML {* @{simpset} *}
  4369 ML {* @{claset} *}
  4370 ML {* @{clasimpset} *}
  4371 
  4372 The same works for sources being ``used'' within an Isar context.
  4373 
  4374 * ML in Isar: improved error reporting; extra verbosity with
  4375 ML_Context.trace enabled.
  4376 
  4377 * Pure/General/table.ML: the join operations now works via exceptions
  4378 DUP/SAME instead of type option. This is simpler in simple cases, and
  4379 admits slightly more efficient complex applications.
  4380 
  4381 * Pure: 'advanced' translation functions (parse_translation etc.) now
  4382 use Context.generic instead of just theory.
  4383 
  4384 * Pure: datatype Context.generic joins theory/Proof.context and
  4385 provides some facilities for code that works in either kind of
  4386 context, notably GenericDataFun for uniform theory and proof data.
  4387 
  4388 * Pure: simplified internal attribute type, which is now always
  4389 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  4390 local (Proof.context) attributes have been discontinued, while
  4391 minimizing code duplication. Thm.rule_attribute and
  4392 Thm.declaration_attribute build canonical attributes; see also structure
  4393 Context for further operations on Context.generic, notably
  4394 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  4395 declarations and definitions.
  4396 
  4397 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  4398 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  4399 init only required for impure data. INCOMPATIBILITY: empty really need
  4400 to be empty (no dependencies on theory content!)
  4401 
  4402 * Pure/kernel: consts certification ignores sort constraints given in
  4403 signature declarations. (This information is not relevant to the
  4404 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  4405 potential INCOMPATIBILITY.
  4406 
  4407 * Pure: axiomatic type classes are now purely definitional, with
  4408 explicit proofs of class axioms and super class relations performed
  4409 internally. See Pure/axclass.ML for the main internal interfaces --
  4410 notably AxClass.define_class supercedes AxClass.add_axclass, and
  4411 AxClass.axiomatize_class/classrel/arity supersede
  4412 Sign.add_classes/classrel/arities.
  4413 
  4414 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  4415 global/local versions on theory vs. Proof.context have been
  4416 discontinued; Attrib.syntax and Method.syntax have been adapted
  4417 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  4418 attributes, methods, etc.
  4419 
  4420 * Pure: several functions of signature "... -> theory -> theory * ..."
  4421 have been reoriented to "... -> theory -> ... * theory" in order to
  4422 allow natural usage in combination with the ||>, ||>>, |-> and
  4423 fold_map combinators.
  4424 
  4425 * Pure: official theorem names (closed derivations) and additional
  4426 comments (tags) are now strictly separate.  Name hints -- which are
  4427 maintained as tags -- may be attached any time without affecting the
  4428 derivation.
  4429 
  4430 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  4431 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  4432 achieve the old behaviour.
  4433 
  4434 * Pure: the "Goal" constant is now called "prop", supporting a
  4435 slightly more general idea of ``protecting'' meta-level rule
  4436 statements.
  4437 
  4438 * Pure: Logic.(un)varify only works in a global context, which is now
  4439 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  4440 Logic.legacy_(un)varify as temporary workaround.
  4441 
  4442 * Pure: structure Name provides scalable operations for generating
  4443 internal variable names, notably Name.variants etc.  This replaces
  4444 some popular functions from term.ML:
  4445 
  4446   Term.variant		->  Name.variant
  4447   Term.variantlist	->  Name.variant_list
  4448   Term.invent_names	->  Name.invent_list
  4449 
  4450 Note that low-level renaming rarely occurs in new code -- operations
  4451 from structure Variable are used instead (see below).
  4452 
  4453 * Pure: structure Variable provides fundamental operations for proper
  4454 treatment of fixed/schematic variables in a context.  For example,
  4455 Variable.import introduces fixes for schematics of given facts and
  4456 Variable.export reverses the effect (up to renaming) -- this replaces
  4457 various freeze_thaw operations.
  4458 
  4459 * Pure: structure Goal provides simple interfaces for
  4460 init/conclude/finish and tactical prove operations (replacing former
  4461 Tactic.prove).  Goal.prove is the canonical way to prove results
  4462 within a given context; Goal.prove_global is a degraded version for
  4463 theory level goals, including a global Drule.standard.  Note that
  4464 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  4465 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  4466 in a locale context).
  4467 
  4468 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  4469 and type checking (Syntax.check_term etc.), with common combinations
  4470 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  4471 which are considered legacy and await removal.
  4472 
  4473 * Pure/Syntax: generic interfaces for type unchecking
  4474 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  4475 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  4476 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  4477 available for convenience, but refer to the very same operations using
  4478 a mere theory instead of a full context.
  4479 
  4480 * Isar: simplified treatment of user-level errors, using exception
  4481 ERROR of string uniformly.  Function error now merely raises ERROR,
  4482 without any side effect on output channels.  The Isar toplevel takes
  4483 care of proper display of ERROR exceptions.  ML code may use plain
  4484 handle/can/try; cat_error may be used to concatenate errors like this:
  4485 
  4486   ... handle ERROR msg => cat_error msg "..."
  4487 
  4488 Toplevel ML code (run directly or through the Isar toplevel) may be
  4489 embedded into the Isar toplevel with exception display/debug like
  4490 this:
  4491 
  4492   Isar.toplevel (fn () => ...)
  4493 
  4494 INCOMPATIBILITY, removed special transform_error facilities, removed
  4495 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  4496 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  4497 -- use plain ERROR instead.
  4498 
  4499 * Isar: theory setup now has type (theory -> theory), instead of a
  4500 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  4501 
  4502 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  4503 ProofContext.debug/verbose flags.
  4504 
  4505 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  4506 theory before entering a proof state.  Transactions now always see a
  4507 quasi-functional intermediate checkpoint, both in interactive and
  4508 batch mode.
  4509 
  4510 * Isar: simplified interfaces for outer syntax.  Renamed
  4511 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  4512 OuterSyntax.add_parsers -- this functionality is now included in
  4513 OuterSyntax.command etc.  INCOMPATIBILITY.
  4514 
  4515 * Simplifier: the simpset of a running simplification process now
  4516 contains a proof context (cf. Simplifier.the_context), which is the
  4517 very context that the initial simpset has been retrieved from (by
  4518 simpset_of/local_simpset_of).  Consequently, all plug-in components
  4519 (solver, looper etc.) may depend on arbitrary proof data.
  4520 
  4521 * Simplifier.inherit_context inherits the proof context (plus the
  4522 local bounds) of the current simplification process; any simproc
  4523 etc. that calls the Simplifier recursively should do this!  Removed
  4524 former Simplifier.inherit_bounds, which is already included here --
  4525 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  4526 specify an explicit context using Simplifier.context/theory_context.
  4527 
  4528 * Simplifier/Classical Reasoner: more abstract interfaces
  4529 change_simpset/claset for modifying the simpset/claset reference of a
  4530 theory; raw versions simpset/claset_ref etc. have been discontinued --
  4531 INCOMPATIBILITY.
  4532 
  4533 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  4534 "Trueprop" etc.
  4535 
  4536 
  4537 *** System ***
  4538 
  4539 * settings: the default heap location within ISABELLE_HOME_USER now
  4540 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  4541 Isabelle installations.
  4542 
  4543 * isabelle-process: option -S (secure mode) disables some critical
  4544 operations, notably runtime compilation and evaluation of ML source
  4545 code.
  4546 
  4547 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  4548 
  4549 * Support for parallel execution, using native multicore support of
  4550 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  4551 independent theories, according to the given theory header
  4552 specifications. The maximum number of worker threads is specified via
  4553 usedir option -M or the "max-threads" setting in Proof General. A
  4554 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  4555 to 6 on a 8-core machine.  User-code needs to observe certain
  4556 guidelines for thread-safe programming, see appendix A in the Isar
  4557 Implementation manual.
  4558 
  4559 
  4560 
  4561 New in Isabelle2005 (October 2005)
  4562 ----------------------------------
  4563 
  4564 *** General ***
  4565 
  4566 * Theory headers: the new header syntax for Isar theories is
  4567 
  4568   theory <name>
  4569   imports <theory1> ... <theoryN>
  4570   uses <file1> ... <fileM>
  4571   begin
  4572 
  4573 where the 'uses' part is optional.  The previous syntax
  4574 
  4575   theory <name> = <theory1> + ... + <theoryN>:
  4576 
  4577 will disappear in the next release.  Use isatool fixheaders to convert
  4578 existing theory files.  Note that there is no change in ancient
  4579 non-Isar theories now, but these will disappear soon.
  4580 
  4581 * Theory loader: parent theories can now also be referred to via
  4582 relative and absolute paths.
  4583 
  4584 * Command 'find_theorems' searches for a list of criteria instead of a
  4585 list of constants. Known criteria are: intro, elim, dest, name:string,
  4586 simp:term, and any term. Criteria can be preceded by '-' to select
  4587 theorems that do not match. Intro, elim, dest select theorems that
  4588 match the current goal, name:s selects theorems whose fully qualified
  4589 name contain s, and simp:term selects all simplification rules whose
  4590 lhs match term.  Any other term is interpreted as pattern and selects
  4591 all theorems matching the pattern. Available in ProofGeneral under
  4592 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  4593 
  4594   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  4595 
  4596 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  4597 matching the current goal as introduction rule and not having "HOL."
  4598 in their name (i.e. not being defined in theory HOL).
  4599 
  4600 * Command 'thms_containing' has been discontinued in favour of
  4601 'find_theorems'; INCOMPATIBILITY.
  4602 
  4603 * Communication with Proof General is now 8bit clean, which means that
  4604 Unicode text in UTF-8 encoding may be used within theory texts (both
  4605 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4606 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4607 
  4608   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4609   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4610 
  4611 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4612 Classical Reasoner.  Typical big applications run around 2 times
  4613 faster.
  4614 
  4615 
  4616 *** Document preparation ***
  4617 
  4618 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4619 of raw sources.  Only those symbols that do not require additional
  4620 LaTeX packages (depending on comments in isabellesym.sty) are
  4621 displayed properly, everything else is left verbatim.  isatool display
  4622 and isatool print are used as front ends (these are subject to the
  4623 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4624 
  4625 * Command tags control specific markup of certain regions of text,
  4626 notably folding and hiding.  Predefined tags include "theory" (for
  4627 theory begin and end), "proof" for proof commands, and "ML" for
  4628 commands involving ML code; the additional tags "visible" and
  4629 "invisible" are unused by default.  Users may give explicit tag
  4630 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4631 interpretation of tags is determined by the LaTeX job during document
  4632 preparation: see option -V of isatool usedir, or options -n and -t of
  4633 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4634 \isadroptag.
  4635 
  4636 Several document versions may be produced at the same time via isatool
  4637 usedir (the generated index.html will link all of them).  Typical
  4638 specifications include ''-V document=theory,proof,ML'' to present
  4639 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4640 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4641 these parts without any formal replacement text.  The Isabelle site
  4642 default settings produce ''document'' and ''outline'' versions as
  4643 specified above.
  4644 
  4645 * Several new antiquotations:
  4646 
  4647   @{term_type term} prints a term with its type annotated;
  4648 
  4649   @{typeof term} prints the type of a term;
  4650 
  4651   @{const const} is the same as @{term const}, but checks that the
  4652   argument is a known logical constant;
  4653 
  4654   @{term_style style term} and @{thm_style style thm} print a term or
  4655   theorem applying a "style" to it
  4656 
  4657   @{ML text}
  4658 
  4659 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4660 definitions, equations, inequations etc., 'concl' printing only the
  4661 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4662 to print the specified premise.  TermStyle.add_style provides an ML
  4663 interface for introducing further styles.  See also the "LaTeX Sugar"
  4664 document practical applications.  The ML antiquotation prints
  4665 type-checked ML expressions verbatim.
  4666 
  4667 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4668 and 'text' support optional locale specification '(in loc)', which
  4669 specifies the default context for interpreting antiquotations.  For
  4670 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4671 
  4672 * Option 'locale=NAME' of antiquotations specifies an alternative
  4673 context interpreting the subsequent argument.  For example: @{thm
  4674 [locale=lattice] inf_assoc}.
  4675 
  4676 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4677 a proof context.
  4678 
  4679 * Proper output of antiquotations for theory commands involving a
  4680 proof context (such as 'locale' or 'theorem (in loc) ...').
  4681 
  4682 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4683 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4684 
  4685 * isatool usedir: new option -C (default true) controls whether option
  4686 -D should include a copy of the original document directory; -C false
  4687 prevents unwanted effects such as copying of administrative CVS data.
  4688 
  4689 
  4690 *** Pure ***
  4691 
  4692 * Considerably improved version of 'constdefs' command.  Now performs
  4693 automatic type-inference of declared constants; additional support for
  4694 local structure declarations (cf. locales and HOL records), see also
  4695 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4696 sequential dependencies of definitions within a single 'constdefs'
  4697 section; moreover, the declared name needs to be an identifier.  If
  4698 all fails, consider to fall back on 'consts' and 'defs' separately.
  4699 
  4700 * Improved indexed syntax and implicit structures.  First of all,
  4701 indexed syntax provides a notational device for subscripted
  4702 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4703 expressions.  Secondly, in a local context with structure
  4704 declarations, number indexes \<^sub>n or the empty index (default
  4705 number 1) refer to a certain fixed variable implicitly; option
  4706 show_structs controls printing of implicit structures.  Typical
  4707 applications of these concepts involve record types and locales.
  4708 
  4709 * New command 'no_syntax' removes grammar declarations (and
  4710 translations) resulting from the given syntax specification, which is
  4711 interpreted in the same manner as for the 'syntax' command.
  4712 
  4713 * 'Advanced' translation functions (parse_translation etc.) may depend
  4714 on the signature of the theory context being presently used for
  4715 parsing/printing, see also isar-ref manual.
  4716 
  4717 * Improved 'oracle' command provides a type-safe interface to turn an
  4718 ML expression of type theory -> T -> term into a primitive rule of
  4719 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4720 is already included here); see also FOL/ex/IffExample.thy;
  4721 INCOMPATIBILITY.
  4722 
  4723 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4724 before); "cI" is no longer bound, use "c.intro" instead.
  4725 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4726 axclasses vs. locales.
  4727 
  4728 * Improved internal renaming of symbolic identifiers -- attach primes
  4729 instead of base 26 numbers.
  4730 
  4731 * New flag show_question_marks controls printing of leading question
  4732 marks in schematic variable names.
  4733 
  4734 * In schematic variable names, *any* symbol following \<^isub> or
  4735 \<^isup> is now treated as part of the base name.  For example, the
  4736 following works without printing of awkward ".0" indexes:
  4737 
  4738   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4739     by simp
  4740 
  4741 * Inner syntax includes (*(*nested*) comments*).
  4742 
  4743 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4744 annotations as "(00...)".
  4745 
  4746 * Clear separation of logical types and nonterminals, where the latter
  4747 may only occur in 'syntax' specifications or type abbreviations.
  4748 Before that distinction was only partially implemented via type class
  4749 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4750 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4751 exotic syntax specifications may require further adaption
  4752 (e.g. Cube/Cube.thy).
  4753 
  4754 * Removed obsolete type class "logic", use the top sort {} instead.
  4755 Note that non-logical types should be declared as 'nonterminals'
  4756 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4757 specifications.
  4758 
  4759 * Attributes 'induct' and 'cases': type or set names may now be
  4760 locally fixed variables as well.
  4761 
  4762 * Simplifier: can now control the depth to which conditional rewriting
  4763 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4764 Limit.
  4765 
  4766 * Simplifier: simplification procedures may now take the current
  4767 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4768 interface), which is very useful for calling the Simplifier
  4769 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4770 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4771 low-level mk_simproc no longer applies Logic.varify internally, to
  4772 allow for use in a context of fixed variables.
  4773 
  4774 * thin_tac now works even if the assumption being deleted contains !!
  4775 or ==>.  More generally, erule now works even if the major premise of
  4776 the elimination rule contains !! or ==>.
  4777 
  4778 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4779 
  4780 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4781 from Pure, which contains all common declarations already.  Both
  4782 theories are defined via plain Isabelle/Isar .thy files.
  4783 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4784 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4785 use isatool fixcpure to adapt your theory and ML sources.
  4786 
  4787 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4788 selections of theorems in named facts via index ranges.
  4789 
  4790 * 'print_theorems': in theory mode, really print the difference
  4791 wrt. the last state (works for interactive theory development only),
  4792 in proof mode print all local facts (cf. 'print_facts');
  4793 
  4794 * 'hide': option '(open)' hides only base names.
  4795 
  4796 * More efficient treatment of intermediate checkpoints in interactive
  4797 theory development.
  4798 
  4799 * Code generator is now invoked via code_module (incremental code
  4800 generation) and code_library (modular code generation, ML structures
  4801 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4802 must be quoted when used as identifiers.
  4803 
  4804 * New 'value' command for reading, evaluating and printing terms using
  4805 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4806 quoted when used as identifier.
  4807 
  4808 
  4809 *** Locales ***
  4810 
  4811 * New commands for the interpretation of locale expressions in
  4812 theories (1), locales (2) and proof contexts (3).  These generate
  4813 proof obligations from the expression specification.  After the
  4814 obligations have been discharged, theorems of the expression are added
  4815 to the theory, target locale or proof context.  The synopsis of the
  4816 commands is a follows:
  4817 
  4818   (1) interpretation expr inst
  4819   (2) interpretation target < expr
  4820   (3) interpret expr inst
  4821 
  4822 Interpretation in theories and proof contexts require a parameter
  4823 instantiation of terms from the current context.  This is applied to
  4824 specifications and theorems of the interpreted expression.
  4825 Interpretation in locales only permits parameter renaming through the
  4826 locale expression.  Interpretation is smart in that interpretations
  4827 that are active already do not occur in proof obligations, neither are
  4828 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4829 inspect active interpretations of a particular locale.  For details,
  4830 see the Isar Reference manual.  Examples can be found in
  4831 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4832 
  4833 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4834 'interpret' instead.
  4835 
  4836 * New context element 'constrains' for adding type constraints to
  4837 parameters.
  4838 
  4839 * Context expressions: renaming of parameters with syntax
  4840 redeclaration.
  4841 
  4842 * Locale declaration: 'includes' disallowed.
  4843 
  4844 * Proper static binding of attribute syntax -- i.e. types / terms /
  4845 facts mentioned as arguments are always those of the locale definition
  4846 context, independently of the context of later invocations.  Moreover,
  4847 locale operations (renaming and type / term instantiation) are applied
  4848 to attribute arguments as expected.
  4849 
  4850 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4851 actual attributes; rare situations may require Attrib.attribute to
  4852 embed those attributes into Attrib.src that lack concrete syntax.
  4853 Attribute implementations need to cooperate properly with the static
  4854 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4855 Attrib.XXX_thm etc. already do the right thing without further
  4856 intervention.  Only unusual applications -- such as "where" or "of"
  4857 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4858 on the context and the facts involved -- may have to assign parsed
  4859 values to argument tokens explicitly.
  4860 
  4861 * Changed parameter management in theorem generation for long goal
  4862 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4863 theorem statement in rare situations.
  4864 
  4865 * Locale inspection command 'print_locale' omits notes elements.  Use
  4866 'print_locale!' to have them included in the output.
  4867 
  4868 
  4869 *** Provers ***
  4870 
  4871 * Provers/hypsubst.ML: improved version of the subst method, for
  4872 single-step rewriting: it now works in bound variable contexts. New is
  4873 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  4874 rewrite a different subterm than the original subst method, which is
  4875 still available as 'simplesubst'.
  4876 
  4877 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  4878 and quasi orders.
  4879 
  4880 * Provers/trancl.ML: new transitivity reasoner for transitive and
  4881 reflexive-transitive closure of relations.
  4882 
  4883 * Provers/blast.ML: new reference depth_limit to make blast's depth
  4884 limit (previously hard-coded with a value of 20) user-definable.
  4885 
  4886 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  4887 is peformed already.  Object-logics merely need to finish their
  4888 initial simpset configuration as before.  INCOMPATIBILITY.
  4889 
  4890 
  4891 *** HOL ***
  4892 
  4893 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  4894 
  4895   syntax (epsilon)
  4896     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  4897 
  4898 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  4899 and x-symbol; use option '-m epsilon' to get it actually printed.
  4900 Moreover, the mathematically important symbolic identifier \<epsilon>
  4901 becomes available as variable, constant etc.  INCOMPATIBILITY,
  4902 
  4903 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  4904 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  4905 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  4906 support corresponding Isar calculations.
  4907 
  4908 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  4909 instead of ":".
  4910 
  4911 * theory SetInterval: changed the syntax for open intervals:
  4912 
  4913   Old       New
  4914   {..n(}    {..<n}
  4915   {)n..}    {n<..}
  4916   {m..n(}   {m..<n}
  4917   {)m..n}   {m<..n}
  4918   {)m..n(}  {m<..<n}
  4919 
  4920 The old syntax is still supported but will disappear in the next
  4921 release.  For conversion use the following Emacs search and replace
  4922 patterns (these are not perfect but work quite well):
  4923 
  4924   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  4925   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  4926 
  4927 * Theory Commutative_Ring (in Library): method comm_ring for proving
  4928 equalities in commutative rings; method 'algebra' provides a generic
  4929 interface.
  4930 
  4931 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  4932 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  4933 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  4934 be a tuple pattern.
  4935 
  4936 Some new syntax forms are available:
  4937 
  4938   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  4939   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  4940   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  4941   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  4942 
  4943 The latter form "\<Sum>x < k. e" used to be based on a separate
  4944 function "Summation", which has been discontinued.
  4945 
  4946 * theory Finite_Set: in structured induction proofs, the insert case
  4947 is now 'case (insert x F)' instead of the old counterintuitive 'case
  4948 (insert F x)'.
  4949 
  4950 * The 'refute' command has been extended to support a much larger
  4951 fragment of HOL, including axiomatic type classes, constdefs and
  4952 typedefs, inductive datatypes and recursion.
  4953 
  4954 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  4955 Requires zChaff with proof generation to be installed.  See
  4956 HOL/ex/SAT_Examples.thy for examples.
  4957 
  4958 * Datatype induction via method 'induct' now preserves the name of the
  4959 induction variable. For example, when proving P(xs::'a list) by
  4960 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  4961 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  4962 in unstructured proof scripts.
  4963 
  4964 * Reworked implementation of records.  Improved scalability for
  4965 records with many fields, avoiding performance problems for type
  4966 inference. Records are no longer composed of nested field types, but
  4967 of nested extension types. Therefore the record type only grows linear
  4968 in the number of extensions and not in the number of fields.  The
  4969 top-level (users) view on records is preserved.  Potential
  4970 INCOMPATIBILITY only in strange cases, where the theory depends on the
  4971 old record representation. The type generated for a record is called
  4972 <record_name>_ext_type.
  4973 
  4974 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  4975 proofs triggered by a record definition or a simproc (if
  4976 quick_and_dirty is enabled).  Definitions of large records can take
  4977 quite long.
  4978 
  4979 New simproc record_upd_simproc for simplification of multiple record
  4980 updates enabled by default.  Moreover, trivial updates are also
  4981 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  4982 occasionally, since simplification is more powerful by default.
  4983 
  4984 * typedef: proper support for polymorphic sets, which contain extra
  4985 type-variables in the term.
  4986 
  4987 * Simplifier: automatically reasons about transitivity chains
  4988 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  4989 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  4990 old proofs break occasionally as simplification may now solve more
  4991 goals than previously.
  4992 
  4993 * Simplifier: converts x <= y into x = y if assumption y <= x is
  4994 present.  Works for all partial orders (class "order"), in particular
  4995 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  4996 just like y <= x.
  4997 
  4998 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  4999 bound variable or a constant then the let is unfolded.  Otherwise
  5000 first a is simplified to b, and then f b is simplified to g. If
  5001 possible we abstract b from g arriving at "let x = b in h x",
  5002 otherwise we unfold the let and arrive at g.  The simproc can be
  5003 enabled/disabled by the reference use_let_simproc.  Potential
  5004 INCOMPATIBILITY since simplification is more powerful by default.
  5005 
  5006 * Classical reasoning: the meson method now accepts theorems as arguments.
  5007 
  5008 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  5009 jobs to provide advice on the provability of subgoals.
  5010 
  5011 * Theory OrderedGroup and Ring_and_Field: various additions and
  5012 improvements to faciliate calculations involving equalities and
  5013 inequalities.
  5014 
  5015 The following theorems have been eliminated or modified
  5016 (INCOMPATIBILITY):
  5017 
  5018   abs_eq             now named abs_of_nonneg
  5019   abs_of_ge_0        now named abs_of_nonneg
  5020   abs_minus_eq       now named abs_of_nonpos
  5021   imp_abs_id         now named abs_of_nonneg
  5022   imp_abs_neg_id     now named abs_of_nonpos
  5023   mult_pos           now named mult_pos_pos
  5024   mult_pos_le        now named mult_nonneg_nonneg
  5025   mult_pos_neg_le    now named mult_nonneg_nonpos
  5026   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  5027   mult_neg           now named mult_neg_neg
  5028   mult_neg_le        now named mult_nonpos_nonpos
  5029 
  5030 * The following lemmas in Ring_and_Field have been added to the simplifier:
  5031      
  5032      zero_le_square
  5033      not_square_less_zero 
  5034 
  5035   The following lemmas have been deleted from Real/RealPow:
  5036   
  5037      realpow_zero_zero
  5038      realpow_two
  5039      realpow_less
  5040      zero_le_power
  5041      realpow_two_le
  5042      abs_realpow_two
  5043      realpow_two_abs     
  5044 
  5045 * Theory Parity: added rules for simplifying exponents.
  5046 
  5047 * Theory List:
  5048 
  5049 The following theorems have been eliminated or modified
  5050 (INCOMPATIBILITY):
  5051 
  5052   list_all_Nil       now named list_all.simps(1)
  5053   list_all_Cons      now named list_all.simps(2)
  5054   list_all_conv      now named list_all_iff
  5055   set_mem_eq         now named mem_iff
  5056 
  5057 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  5058 asymptotic "big O" calculations.  See the notes in BigO.thy.
  5059 
  5060 
  5061 *** HOL-Complex ***
  5062 
  5063 * Theory RealDef: better support for embedding natural numbers and
  5064 integers in the reals.
  5065 
  5066 The following theorems have been eliminated or modified
  5067 (INCOMPATIBILITY):
  5068 
  5069   exp_ge_add_one_self  now requires no hypotheses
  5070   real_of_int_add      reversed direction of equality (use [symmetric])
  5071   real_of_int_minus    reversed direction of equality (use [symmetric])
  5072   real_of_int_diff     reversed direction of equality (use [symmetric])
  5073   real_of_int_mult     reversed direction of equality (use [symmetric])
  5074 
  5075 * Theory RComplete: expanded support for floor and ceiling functions.
  5076 
  5077 * Theory Ln is new, with properties of the natural logarithm
  5078 
  5079 * Hyperreal: There is a new type constructor "star" for making
  5080 nonstandard types.  The old type names are now type synonyms:
  5081 
  5082   hypreal = real star
  5083   hypnat = nat star
  5084   hcomplex = complex star
  5085 
  5086 * Hyperreal: Many groups of similarly-defined constants have been
  5087 replaced by polymorphic versions (INCOMPATIBILITY):
  5088 
  5089   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  5090 
  5091   starset      <-- starsetNat, starsetC
  5092   *s*          <-- *sNat*, *sc*
  5093   starset_n    <-- starsetNat_n, starsetC_n
  5094   *sn*         <-- *sNatn*, *scn*
  5095   InternalSets <-- InternalNatSets, InternalCSets
  5096 
  5097   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  5098   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  5099   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  5100   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  5101   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  5102 
  5103 * Hyperreal: Many type-specific theorems have been removed in favor of
  5104 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  5105 
  5106   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  5107   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  5108   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  5109   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  5110   right_minus <-- hypreal_add_minus
  5111   left_minus <-- {hypreal,hcomplex}_add_minus_left
  5112   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  5113   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  5114   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  5115   mult_1_right <-- hcomplex_mult_one_right
  5116   mult_zero_left <-- hcomplex_mult_zero_left
  5117   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  5118   right_distrib <-- hypnat_add_mult_distrib2
  5119   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  5120   right_inverse <-- hypreal_mult_inverse
  5121   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  5122   order_refl <-- {hypreal,hypnat}_le_refl
  5123   order_trans <-- {hypreal,hypnat}_le_trans
  5124   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  5125   order_less_le <-- {hypreal,hypnat}_less_le
  5126   linorder_linear <-- {hypreal,hypnat}_le_linear
  5127   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  5128   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  5129   add_nonneg_nonneg <-- hypreal_le_add_order
  5130 
  5131 * Hyperreal: Separate theorems having to do with type-specific
  5132 versions of constants have been merged into theorems that apply to the
  5133 new polymorphic constants (INCOMPATIBILITY):
  5134 
  5135   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  5136   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  5137   STAR_Un <-- {STAR,NatStar,STARC}_Un
  5138   STAR_Int <-- {STAR,NatStar,STARC}_Int
  5139   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  5140   STAR_subset <-- {STAR,NatStar,STARC}_subset
  5141   STAR_mem <-- {STAR,NatStar,STARC}_mem
  5142   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  5143   STAR_diff <-- {STAR,STARC}_diff
  5144   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  5145     STARC_hcomplex_of_complex}_image_subset
  5146   starset_n_Un <-- starset{Nat,C}_n_Un
  5147   starset_n_Int <-- starset{Nat,C}_n_Int
  5148   starset_n_Compl <-- starset{Nat,C}_n_Compl
  5149   starset_n_diff <-- starset{Nat,C}_n_diff
  5150   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  5151   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  5152   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  5153   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  5154   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  5155   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  5156   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  5157   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  5158   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  5159   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  5160   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  5161   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  5162   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  5163   starfun_diff <-- starfun{C,RC,CR}_diff
  5164   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  5165   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  5166   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  5167   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  5168   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  5169   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  5170   starfun_Id <-- starfunC_Id
  5171   starfun_approx <-- starfun{Nat,CR}_approx
  5172   starfun_capprox <-- starfun{C,RC}_capprox
  5173   starfun_abs <-- starfunNat_rabs
  5174   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  5175   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  5176   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  5177   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  5178   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  5179   starfun_add_approx <-- starfunCR_add_approx
  5180   starfun_inverse_inverse <-- starfunC_inverse_inverse
  5181   starfun_divide <-- starfun{C,CR,RC}_divide
  5182   starfun_n <-- starfun{Nat,C}_n
  5183   starfun_n_mult <-- starfun{Nat,C}_n_mult
  5184   starfun_n_add <-- starfun{Nat,C}_n_add
  5185   starfun_n_add_minus <-- starfunNat_n_add_minus
  5186   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  5187   starfun_n_minus <-- starfun{Nat,C}_n_minus
  5188   starfun_n_eq <-- starfun{Nat,C}_n_eq
  5189 
  5190   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  5191   star_n_minus <-- {hypreal,hcomplex}_minus
  5192   star_n_diff <-- {hypreal,hcomplex}_diff
  5193   star_n_mult <-- {hypreal,hcomplex}_mult
  5194   star_n_inverse <-- {hypreal,hcomplex}_inverse
  5195   star_n_le <-- {hypreal,hypnat}_le
  5196   star_n_less <-- {hypreal,hypnat}_less
  5197   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  5198   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  5199   star_n_abs <-- hypreal_hrabs
  5200   star_n_divide <-- hcomplex_divide
  5201 
  5202   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  5203   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  5204   star_of_diff <-- hypreal_of_real_diff
  5205   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  5206   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  5207   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  5208   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  5209   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  5210   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  5211   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  5212   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  5213   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  5214   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  5215   star_of_number_of <-- {hypreal,hcomplex}_number_of
  5216   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  5217   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  5218   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  5219   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  5220   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  5221   star_of_power <-- hypreal_of_real_power
  5222   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  5223 
  5224 * Hyperreal: new method "transfer" that implements the transfer
  5225 principle of nonstandard analysis. With a subgoal that mentions
  5226 nonstandard types like "'a star", the command "apply transfer"
  5227 replaces it with an equivalent one that mentions only standard types.
  5228 To be successful, all free variables must have standard types; non-
  5229 standard variables must have explicit universal quantifiers.
  5230 
  5231 * Hyperreal: A theory of Taylor series.
  5232 
  5233 
  5234 *** HOLCF ***
  5235 
  5236 * Discontinued special version of 'constdefs' (which used to support
  5237 continuous functions) in favor of the general Pure one with full
  5238 type-inference.
  5239 
  5240 * New simplification procedure for solving continuity conditions; it
  5241 is much faster on terms with many nested lambda abstractions (cubic
  5242 instead of exponential time).
  5243 
  5244 * New syntax for domain package: selector names are now optional.
  5245 Parentheses should be omitted unless argument is lazy, for example:
  5246 
  5247   domain 'a stream = cons "'a" (lazy "'a stream")
  5248 
  5249 * New command 'fixrec' for defining recursive functions with pattern
  5250 matching; defining multiple functions with mutual recursion is also
  5251 supported.  Patterns may include the constants cpair, spair, up, sinl,
  5252 sinr, or any data constructor defined by the domain package. The given
  5253 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  5254 syntax and examples.
  5255 
  5256 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  5257 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  5258 but the proof obligation additionally includes an admissibility
  5259 requirement. The packages generate instances of class cpo or pcpo,
  5260 with continuity and strictness theorems for Rep and Abs.
  5261 
  5262 * HOLCF: Many theorems have been renamed according to a more standard naming
  5263 scheme (INCOMPATIBILITY):
  5264 
  5265   foo_inject:  "foo$x = foo$y ==> x = y"
  5266   foo_eq:      "(foo$x = foo$y) = (x = y)"
  5267   foo_less:    "(foo$x << foo$y) = (x << y)"
  5268   foo_strict:  "foo$UU = UU"
  5269   foo_defined: "... ==> foo$x ~= UU"
  5270   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  5271 
  5272 
  5273 *** ZF ***
  5274 
  5275 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  5276 including the First Isomorphism Theorem (on quotienting by the kernel
  5277 of a homomorphism).
  5278 
  5279 * ZF/Simplifier: install second copy of type solver that actually
  5280 makes use of TC rules declared to Isar proof contexts (or locales);
  5281 the old version is still required for ML proof scripts.
  5282 
  5283 
  5284 *** Cube ***
  5285 
  5286 * Converted to Isar theory format; use locales instead of axiomatic
  5287 theories.
  5288 
  5289 
  5290 *** ML ***
  5291 
  5292 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  5293 for ||>, ||>>, |>>,
  5294 
  5295 * Pure/library.ML no longer defines its own option datatype, but uses
  5296 that of the SML basis, which has constructors NONE and SOME instead of
  5297 None and Some, as well as exception Option.Option instead of OPTION.
  5298 The functions the, if_none, is_some, is_none have been adapted
  5299 accordingly, while Option.map replaces apsome.
  5300 
  5301 * Pure/library.ML: the exception LIST has been given up in favour of
  5302 the standard exceptions Empty and Subscript, as well as
  5303 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  5304 superceded by the standard hd and tl functions etc.
  5305 
  5306 A number of basic list functions are no longer exported to the ML
  5307 toplevel, as they are variants of predefined functions.  The following
  5308 suggests how one can translate existing code:
  5309 
  5310     rev_append xs ys = List.revAppend (xs, ys)
  5311     nth_elem (i, xs) = List.nth (xs, i)
  5312     last_elem xs = List.last xs
  5313     flat xss = List.concat xss
  5314     seq fs = List.app fs
  5315     partition P xs = List.partition P xs
  5316     mapfilter f xs = List.mapPartial f xs
  5317 
  5318 * Pure/library.ML: several combinators for linear functional
  5319 transformations, notably reverse application and composition:
  5320 
  5321   x |> f                f #> g
  5322   (x, y) |-> f          f #-> g
  5323 
  5324 * Pure/library.ML: introduced/changed precedence of infix operators:
  5325 
  5326   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  5327   infix 2 ?;
  5328   infix 3 o oo ooo oooo;
  5329   infix 4 ~~ upto downto;
  5330 
  5331 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  5332 infix operators.
  5333 
  5334 * Pure/library.ML: natural list combinators fold, fold_rev, and
  5335 fold_map support linear functional transformations and nesting.  For
  5336 example:
  5337 
  5338   fold f [x1, ..., xN] y =
  5339     y |> f x1 |> ... |> f xN
  5340 
  5341   (fold o fold) f [xs1, ..., xsN] y =
  5342     y |> fold f xs1 |> ... |> fold f xsN
  5343 
  5344   fold f [x1, ..., xN] =
  5345     f x1 #> ... #> f xN
  5346 
  5347   (fold o fold) f [xs1, ..., xsN] =
  5348     fold f xs1 #> ... #> fold f xsN
  5349 
  5350 * Pure/library.ML: the following selectors on type 'a option are
  5351 available:
  5352 
  5353   the:               'a option -> 'a  (*partial*)
  5354   these:             'a option -> 'a  where 'a = 'b list
  5355   the_default: 'a -> 'a option -> 'a
  5356   the_list:          'a option -> 'a list
  5357 
  5358 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5359 basic operations for association lists, following natural argument
  5360 order; moreover the explicit equality predicate passed here avoids
  5361 potentially expensive polymorphic runtime equality checks.
  5362 The old functions may be expressed as follows:
  5363 
  5364   assoc = uncurry (AList.lookup (op =))
  5365   assocs = these oo AList.lookup (op =)
  5366   overwrite = uncurry (AList.update (op =)) o swap
  5367 
  5368 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5369 
  5370   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  5371   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  5372 
  5373 replacing make_keylist and keyfilter (occassionally used)
  5374 Naive rewrites:
  5375 
  5376   make_keylist = AList.make
  5377   keyfilter = AList.find (op =)
  5378 
  5379 * eq_fst and eq_snd now take explicit equality parameter, thus
  5380   avoiding eqtypes. Naive rewrites:
  5381 
  5382     eq_fst = eq_fst (op =)
  5383     eq_snd = eq_snd (op =)
  5384 
  5385 * Removed deprecated apl and apr (rarely used).
  5386   Naive rewrites:
  5387 
  5388     apl (n, op) =>>= curry op n
  5389     apr (op, m) =>>= fn n => op (n, m)
  5390 
  5391 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  5392 provides a reasonably efficient light-weight implementation of sets as
  5393 lists.
  5394 
  5395 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  5396 few new operations; existing lookup and update are now curried to
  5397 follow natural argument order (for use with fold etc.);
  5398 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  5399 
  5400 * Pure/General: output via the Isabelle channels of
  5401 writeln/warning/error etc. is now passed through Output.output, with a
  5402 hook for arbitrary transformations depending on the print_mode
  5403 (cf. Output.add_mode -- the first active mode that provides a output
  5404 function wins).  Already formatted output may be embedded into further
  5405 text via Output.raw; the result of Pretty.string_of/str_of and derived
  5406 functions (string_of_term/cterm/thm etc.) is already marked raw to
  5407 accommodate easy composition of diagnostic messages etc.  Programmers
  5408 rarely need to care about Output.output or Output.raw at all, with
  5409 some notable exceptions: Output.output is required when bypassing the
  5410 standard channels (writeln etc.), or in token translations to produce
  5411 properly formatted results; Output.raw is required when capturing
  5412 already output material that will eventually be presented to the user
  5413 a second time.  For the default print mode, both Output.output and
  5414 Output.raw have no effect.
  5415 
  5416 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  5417 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  5418 cumulative results are displayed at the end of a batch session.
  5419 
  5420 * Pure/General: File.sysify_path and File.quote_sysify path have been
  5421 replaced by File.platform_path and File.shell_path (with appropriate
  5422 hooks).  This provides a clean interface for unusual systems where the
  5423 internal and external process view of file names are different.
  5424 
  5425 * Pure: more efficient orders for basic syntactic entities: added
  5426 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  5427 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  5428 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  5429 orders now -- potential INCOMPATIBILITY for code that depends on a
  5430 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  5431 Library.sort_strings on result).
  5432 
  5433 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  5434 fold_types traverse types/terms from left to right, observing natural
  5435 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  5436 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  5437 
  5438 * Pure: name spaces have been refined, with significant changes of the
  5439 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  5440 to extern(_table).  The plain name entry path is superceded by a
  5441 general 'naming' context, which also includes the 'policy' to produce
  5442 a fully qualified name and external accesses of a fully qualified
  5443 name; NameSpace.extend is superceded by context dependent
  5444 Sign.declare_name.  Several theory and proof context operations modify
  5445 the naming context.  Especially note Theory.restore_naming and
  5446 ProofContext.restore_naming to get back to a sane state; note that
  5447 Theory.add_path is no longer sufficient to recover from
  5448 Theory.absolute_path in particular.
  5449 
  5450 * Pure: new flags short_names (default false) and unique_names
  5451 (default true) for controlling output of qualified names.  If
  5452 short_names is set, names are printed unqualified.  If unique_names is
  5453 reset, the name prefix is reduced to the minimum required to achieve
  5454 the original result when interning again, even if there is an overlap
  5455 with earlier declarations.
  5456 
  5457 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  5458 now 'extend', and 'merge' gets an additional Pretty.pp argument
  5459 (useful for printing error messages).  INCOMPATIBILITY.
  5460 
  5461 * Pure: major reorganization of the theory context.  Type Sign.sg and
  5462 Theory.theory are now identified, referring to the universal
  5463 Context.theory (see Pure/context.ML).  Actual signature and theory
  5464 content is managed as theory data.  The old code and interfaces were
  5465 spread over many files and structures; the new arrangement introduces
  5466 considerable INCOMPATIBILITY to gain more clarity:
  5467 
  5468   Context -- theory management operations (name, identity, inclusion,
  5469     parents, ancestors, merge, etc.), plus generic theory data;
  5470 
  5471   Sign -- logical signature and syntax operations (declaring consts,
  5472     types, etc.), plus certify/read for common entities;
  5473 
  5474   Theory -- logical theory operations (stating axioms, definitions,
  5475     oracles), plus a copy of logical signature operations (consts,
  5476     types, etc.); also a few basic management operations (Theory.copy,
  5477     Theory.merge, etc.)
  5478 
  5479 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  5480 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  5481 for convenience -- they merely return the theory.
  5482 
  5483 * Pure: type Type.tsig is superceded by theory in most interfaces.
  5484 
  5485 * Pure: the Isar proof context type is already defined early in Pure
  5486 as Context.proof (note that ProofContext.context and Proof.context are
  5487 aliases, where the latter is the preferred name).  This enables other
  5488 Isabelle components to refer to that type even before Isar is present.
  5489 
  5490 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  5491 typeK, constK, axiomK, oracleK), but provide explicit operations for
  5492 any of these kinds.  For example, Sign.intern typeK is now
  5493 Sign.intern_type, Theory.hide_space Sign.typeK is now
  5494 Theory.hide_types.  Also note that former
  5495 Theory.hide_classes/types/consts are now
  5496 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  5497 internalize their arguments!  INCOMPATIBILITY.
  5498 
  5499 * Pure: get_thm interface (of PureThy and ProofContext) expects
  5500 datatype thmref (with constructors Name and NameSelection) instead of
  5501 plain string -- INCOMPATIBILITY;
  5502 
  5503 * Pure: cases produced by proof methods specify options, where NONE
  5504 means to remove case bindings -- INCOMPATIBILITY in
  5505 (RAW_)METHOD_CASES.
  5506 
  5507 * Pure: the following operations retrieve axioms or theorems from a
  5508 theory node or theory hierarchy, respectively:
  5509 
  5510   Theory.axioms_of: theory -> (string * term) list
  5511   Theory.all_axioms_of: theory -> (string * term) list
  5512   PureThy.thms_of: theory -> (string * thm) list
  5513   PureThy.all_thms_of: theory -> (string * thm) list
  5514 
  5515 * Pure: print_tac now outputs the goal through the trace channel.
  5516 
  5517 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  5518 Reference Toplevel.debug (default false) controls detailed printing
  5519 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  5520 controls execution profiling -- set to 1 for time and 2 for space
  5521 (both increase the runtime).
  5522 
  5523 * Isar session: The initial use of ROOT.ML is now always timed,
  5524 i.e. the log will show the actual process times, in contrast to the
  5525 elapsed wall-clock time that the outer shell wrapper produces.
  5526 
  5527 * Simplifier: improved handling of bound variables (nameless
  5528 representation, avoid allocating new strings).  Simprocs that invoke
  5529 the Simplifier recursively should use Simplifier.inherit_bounds to
  5530 avoid local name clashes.  Failure to do so produces warnings
  5531 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  5532 for further details.
  5533 
  5534 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  5535 bindings for all theorems stored within a given theory; this may help
  5536 in porting non-Isar theories to Isar ones, while keeping ML proof
  5537 scripts for the time being.
  5538 
  5539 * ML operator HTML.with_charset specifies the charset begin used for
  5540 generated HTML files.  For example:
  5541 
  5542   HTML.with_charset "utf-8" use_thy "Hebrew";
  5543   HTML.with_charset "utf-8" use_thy "Chinese";
  5544 
  5545 
  5546 *** System ***
  5547 
  5548 * Allow symlinks to all proper Isabelle executables (Isabelle,
  5549 isabelle, isatool etc.).
  5550 
  5551 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  5552 isatool doc, isatool mkdir, display_drafts etc.).
  5553 
  5554 * isatool usedir: option -f allows specification of the ML file to be
  5555 used by Isabelle; default is ROOT.ML.
  5556 
  5557 * New isatool version outputs the version identifier of the Isabelle
  5558 distribution being used.
  5559 
  5560 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  5561 (containing Boolean satisfiability problems) into Isabelle/HOL
  5562 theories.
  5563 
  5564 
  5565 
  5566 New in Isabelle2004 (April 2004)
  5567 --------------------------------
  5568 
  5569 *** General ***
  5570 
  5571 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  5572   Replaces linorder.ML.
  5573 
  5574 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  5575   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  5576   (\<a>...\<z>), are now considered normal letters, and can therefore
  5577   be used anywhere where an ASCII letter (a...zA...Z) has until
  5578   now. COMPATIBILITY: This obviously changes the parsing of some
  5579   terms, especially where a symbol has been used as a binder, say
  5580   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  5581   as an identifier.  Fix it by inserting a space around former
  5582   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  5583   existing theory and ML files.
  5584 
  5585 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  5586 
  5587 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  5588   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  5589   a normal (but invisible) letter. For multiple letter subscripts repeat
  5590   \<^isub> like this: x\<^isub>1\<^isub>2.
  5591 
  5592 * Pure: There are now sub-/superscripts that can span more than one
  5593   character. Text between \<^bsub> and \<^esub> is set in subscript in
  5594   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  5595   superscript. The new control characters are not identifier parts.
  5596 
  5597 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5598   content of "..." to the latex file instead of \isacntrl... . The "..."
  5599   may consist of any printable characters excluding the end bracket >.
  5600 
  5601 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5602   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5603   declare constants "final", which prevents their being given a definition
  5604   later.  It is useful for constants whose behaviour is fixed axiomatically
  5605   rather than definitionally, such as the meta-logic connectives.
  5606 
  5607 * Pure: 'instance' now handles general arities with general sorts
  5608   (i.e. intersections of classes),
  5609 
  5610 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5611   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5612   It can be changed to alter the colors/layout of generated pages.
  5613 
  5614 
  5615 *** Isar ***
  5616 
  5617 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5618   cut_tac, subgoal_tac and thin_tac:
  5619   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5620     locales are no longer forced to write Isar proof scripts.
  5621     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5622     emulations.
  5623   - INCOMPATIBILITY: names of variables to be instantiated may no
  5624     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5625     This is consistent with the instantiation attribute "where".
  5626 
  5627 * Attributes "where" and "of":
  5628   - Now take type variables of instantiated theorem into account when reading
  5629     the instantiation string.  This fixes a bug that caused instantiated
  5630     theorems to have too special types in some circumstances.
  5631   - "where" permits explicit instantiations of type variables.
  5632 
  5633 * Calculation commands "moreover" and "also" no longer interfere with
  5634   current facts ("this"), admitting arbitrary combinations with "then"
  5635   and derived forms.
  5636 
  5637 * Locales:
  5638   - Goal statements involving the context element "includes" no longer
  5639     generate theorems with internal delta predicates (those ending on
  5640     "_axioms") in the premise.
  5641     Resolve particular premise with <locale>.intro to obtain old form.
  5642   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5643     specification and "includes" elements in goal statement.
  5644   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5645     [intro?] and [elim?] (respectively) by default.
  5646   - Experimental command for instantiation of locales in proof contexts:
  5647         instantiate <label>[<attrs>]: <loc>
  5648     Instantiates locale <loc> and adds all its theorems to the current context
  5649     taking into account their attributes.  Label and attrs are optional
  5650     modifiers, like in theorem declarations.  If present, names of
  5651     instantiated theorems are qualified with <label>, and the attributes
  5652     <attrs> are applied after any attributes these theorems might have already.
  5653       If the locale has assumptions, a chained fact of the form
  5654     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5655     are derived.  The command does not support old-style locales declared
  5656     with "locale (open)".
  5657       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5658 
  5659 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5660   (Isar) contexts.
  5661 
  5662 
  5663 *** HOL ***
  5664 
  5665 * Proof import: new image HOL4 contains the imported library from
  5666   the HOL4 system with about 2500 theorems. It is imported by
  5667   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5668   can be used like any other Isabelle image.  See
  5669   HOL/Import/HOL/README for more information.
  5670 
  5671 * Simplifier:
  5672   - Much improved handling of linear and partial orders.
  5673     Reasoners for linear and partial orders are set up for type classes
  5674     "linorder" and "order" respectively, and are added to the default simpset
  5675     as solvers.  This means that the simplifier can build transitivity chains
  5676     to solve goals from the assumptions.
  5677   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5678     of blast or auto after simplification become unnecessary because the goal
  5679     is solved by simplification already.
  5680 
  5681 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5682     all proved in axiomatic type classes for semirings, rings and fields.
  5683 
  5684 * Numerics:
  5685   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5686     now formalized using the Ring_and_Field theory mentioned above.
  5687   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5688     than before, because now they are set up once in a generic manner.
  5689   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5690     Look for the general versions in Ring_and_Field (and Power if they concern
  5691     exponentiation).
  5692 
  5693 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5694 
  5695 * Records:
  5696   - Record types are now by default printed with their type abbreviation
  5697     instead of the list of all field types. This can be configured via
  5698     the reference "print_record_type_abbr".
  5699   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5700     (not enabled by default).
  5701   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5702     EX x. x = sel r to True (not enabled by default).
  5703   - Tactic "record_split_simp_tac" to split and simplify records added.
  5704 
  5705 * 'specification' command added, allowing for definition by
  5706   specification.  There is also an 'ax_specification' command that
  5707   introduces the new constants axiomatically.
  5708 
  5709 * arith(_tac) is now able to generate counterexamples for reals as well.
  5710 
  5711 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5712 
  5713 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5714   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5715 
  5716 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5717   matrix theory to linear programming.
  5718 
  5719 * Unions and Intersections:
  5720   The latex output syntax of UN and INT has been changed
  5721   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5722   i.e. the index formulae has become a subscript.
  5723   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5724 
  5725 * Unions and Intersections over Intervals:
  5726   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5727   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5728   like in normal math, and corresponding versions for < and for intersection.
  5729 
  5730 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5731   lexicographic dictonary ordering has been added as "lexord".
  5732 
  5733 * ML: the legacy theory structures Int and List have been removed. They had
  5734   conflicted with ML Basis Library structures having the same names.
  5735 
  5736 * 'refute' command added to search for (finite) countermodels.  Only works
  5737   for a fragment of HOL.  The installation of an external SAT solver is
  5738   highly recommended.  See "HOL/Refute.thy" for details.
  5739 
  5740 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5741   formulae under an assignment of free variables to random values.
  5742   In contrast to 'refute', it can deal with inductive datatypes,
  5743   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5744   for examples.
  5745 
  5746 
  5747 *** HOLCF ***
  5748 
  5749 * Streams now come with concatenation and are part of the HOLCF image
  5750 
  5751 
  5752 
  5753 New in Isabelle2003 (May 2003)
  5754 ------------------------------
  5755 
  5756 *** General ***
  5757 
  5758 * Provers/simplifier:
  5759 
  5760   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5761     Assumptions are now subject to complete mutual simplification,
  5762     not just from left to right. The simplifier now preserves
  5763     the order of assumptions.
  5764 
  5765     Potential INCOMPATIBILITY:
  5766 
  5767     -- simp sometimes diverges where the old version did
  5768        not, e.g. invoking simp on the goal
  5769 
  5770         [| P (f x); y = x; f x = f y |] ==> Q
  5771 
  5772        now gives rise to the infinite reduction sequence
  5773 
  5774         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5775 
  5776        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5777        kind of problem.
  5778 
  5779     -- Tactics combining classical reasoner and simplification (such as auto)
  5780        are also affected by this change, because many of them rely on
  5781        simp. They may sometimes diverge as well or yield a different numbers
  5782        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5783        in case of problems. Sometimes subsequent calls to the classical
  5784        reasoner will fail because a preceeding call to the simplifier too
  5785        eagerly simplified the goal, e.g. deleted redundant premises.
  5786 
  5787   - The simplifier trace now shows the names of the applied rewrite rules
  5788 
  5789   - You can limit the number of recursive invocations of the simplifier
  5790     during conditional rewriting (where the simplifie tries to solve the
  5791     conditions before applying the rewrite rule):
  5792     ML "simp_depth_limit := n"
  5793     where n is an integer. Thus you can force termination where previously
  5794     the simplifier would diverge.
  5795 
  5796   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5797 
  5798   - No longer aborts on failed congruence proof.  Instead, the
  5799     congruence is ignored.
  5800 
  5801 * Pure: New generic framework for extracting programs from constructive
  5802   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5803   as HOL/Extraction for some case studies.
  5804 
  5805 * Pure: The main goal of the proof state is no longer shown by default, only
  5806 the subgoals. This behaviour is controlled by a new flag.
  5807    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5808 (ML: Proof.show_main_goal).
  5809 
  5810 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5811 rules whose conclusion matches subgoal 1:
  5812       PG menu: Isabelle/Isar -> Show me -> matching rules
  5813 The rules are ordered by how closely they match the subgoal.
  5814 In particular, rules that solve a subgoal outright are displayed first
  5815 (or rather last, the way they are printed).
  5816 (ML: ProofGeneral.print_intros())
  5817 
  5818 * Pure: New flag trace_unify_fail causes unification to print
  5819 diagnostic information (PG: in trace buffer) when it fails. This is
  5820 useful for figuring out why single step proofs like rule, erule or
  5821 assumption failed.
  5822 
  5823 * Pure: Locale specifications now produce predicate definitions
  5824 according to the body of text (covering assumptions modulo local
  5825 definitions); predicate "loc_axioms" covers newly introduced text,
  5826 while "loc" is cumulative wrt. all included locale expressions; the
  5827 latter view is presented only on export into the global theory
  5828 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5829 on the old view without predicates;
  5830 
  5831 * Pure: predefined locales "var" and "struct" are useful for sharing
  5832 parameters (as in CASL, for example); just specify something like
  5833 ``var x + var y + struct M'' as import;
  5834 
  5835 * Pure: improved thms_containing: proper indexing of facts instead of
  5836 raw theorems; check validity of results wrt. current name space;
  5837 include local facts of proof configuration (also covers active
  5838 locales), cover fixed variables in index; may use "_" in term
  5839 specification; an optional limit for the number of printed facts may
  5840 be given (the default is 40);
  5841 
  5842 * Pure: disallow duplicate fact bindings within new-style theory files
  5843 (batch-mode only);
  5844 
  5845 * Provers: improved induct method: assumptions introduced by case
  5846 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5847 the goal statement); "foo" still refers to all facts collectively;
  5848 
  5849 * Provers: the function blast.overloaded has been removed: all constants
  5850 are regarded as potentially overloaded, which improves robustness in exchange
  5851 for slight decrease in efficiency;
  5852 
  5853 * Provers/linorder: New generic prover for transitivity reasoning over
  5854 linear orders.  Note: this prover is not efficient!
  5855 
  5856 * Isar: preview of problems to finish 'show' now produce an error
  5857 rather than just a warning (in interactive mode);
  5858 
  5859 
  5860 *** HOL ***
  5861 
  5862 * arith(_tac)
  5863 
  5864  - Produces a counter example if it cannot prove a goal.
  5865    Note that the counter example may be spurious if the goal is not a formula
  5866    of quantifier-free linear arithmetic.
  5867    In ProofGeneral the counter example appears in the trace buffer.
  5868 
  5869  - Knows about div k and mod k where k is a numeral of type nat or int.
  5870 
  5871  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  5872    linear arithmetic fails. This takes account of quantifiers and divisibility.
  5873    Presburger arithmetic can also be called explicitly via presburger(_tac).
  5874 
  5875 * simp's arithmetic capabilities have been enhanced a bit: it now
  5876 takes ~= in premises into account (by performing a case split);
  5877 
  5878 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  5879 are distributed over a sum of terms;
  5880 
  5881 * New tactic "trans_tac" and method "trans" instantiate
  5882 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  5883 "<=", "<" and "=").
  5884 
  5885 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  5886 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  5887 
  5888 * 'typedef' command has new option "open" to suppress the set
  5889 definition;
  5890 
  5891 * functions Min and Max on finite sets have been introduced (theory
  5892 Finite_Set);
  5893 
  5894 * attribute [symmetric] now works for relations as well; it turns
  5895 (x,y) : R^-1 into (y,x) : R, and vice versa;
  5896 
  5897 * induct over a !!-quantified statement (say !!x1..xn):
  5898   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  5899 
  5900 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  5901 %x. None. Warning: empty_def now refers to the previously hidden definition
  5902 of the empty set.
  5903 
  5904 * Algebra: formalization of classical algebra.  Intended as base for
  5905 any algebraic development in Isabelle.  Currently covers group theory
  5906 (up to Sylow's theorem) and ring theory (Universal Property of
  5907 Univariate Polynomials).  Contributions welcome;
  5908 
  5909 * GroupTheory: deleted, since its material has been moved to Algebra;
  5910 
  5911 * Complex: new directory of the complex numbers with numeric constants,
  5912 nonstandard complex numbers, and some complex analysis, standard and
  5913 nonstandard (Jacques Fleuriot);
  5914 
  5915 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  5916 
  5917 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  5918 Fleuriot);
  5919 
  5920 * Real/HahnBanach: updated and adapted to locales;
  5921 
  5922 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  5923 Gray and Kramer);
  5924 
  5925 * UNITY: added the Meier-Sanders theory of progress sets;
  5926 
  5927 * MicroJava: bytecode verifier and lightweight bytecode verifier
  5928 as abstract algorithms, instantiated to the JVM;
  5929 
  5930 * Bali: Java source language formalization. Type system, operational
  5931 semantics, axiomatic semantics. Supported language features:
  5932 classes, interfaces, objects,virtual methods, static methods,
  5933 static/instance fields, arrays, access modifiers, definite
  5934 assignment, exceptions.
  5935 
  5936 
  5937 *** ZF ***
  5938 
  5939 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  5940 universe, etc.);
  5941 
  5942 * Main ZF: virtually all theories converted to new-style format;
  5943 
  5944 
  5945 *** ML ***
  5946 
  5947 * Pure: Tactic.prove provides sane interface for internal proofs;
  5948 omits the infamous "standard" operation, so this is more appropriate
  5949 than prove_goalw_cterm in many situations (e.g. in simprocs);
  5950 
  5951 * Pure: improved error reporting of simprocs;
  5952 
  5953 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  5954 up simprocs;
  5955 
  5956 
  5957 *** Document preparation ***
  5958 
  5959 * uses \par instead of \\ for line breaks in theory text. This may
  5960 shift some page breaks in large documents. To get the old behaviour
  5961 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  5962 
  5963 * minimized dependencies of isabelle.sty and isabellesym.sty on
  5964 other packages
  5965 
  5966 * \<euro> now needs package babel/greek instead of marvosym (which
  5967 broke \Rightarrow)
  5968 
  5969 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  5970 textcomp package)
  5971 
  5972 
  5973 
  5974 New in Isabelle2002 (March 2002)
  5975 --------------------------------
  5976 
  5977 *** Document preparation ***
  5978 
  5979 * greatly simplified document preparation setup, including more
  5980 graceful interpretation of isatool usedir -i/-d/-D options, and more
  5981 instructive isatool mkdir; users should basically be able to get
  5982 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  5983 users may run a separate document processing stage manually like this:
  5984 "isatool usedir -D output HOL Test && isatool document Test/output";
  5985 
  5986 * theory dependency graph may now be incorporated into documents;
  5987 isatool usedir -g true will produce session_graph.eps/.pdf for use
  5988 with \includegraphics of LaTeX;
  5989 
  5990 * proper spacing of consecutive markup elements, especially text
  5991 blocks after section headings;
  5992 
  5993 * support bold style (for single symbols only), input syntax is like
  5994 this: "\<^bold>\<alpha>" or "\<^bold>A";
  5995 
  5996 * \<bullet> is now output as bold \cdot by default, which looks much
  5997 better in printed text;
  5998 
  5999 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  6000 note that these symbols are currently unavailable in Proof General /
  6001 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  6002 
  6003 * isatool latex no longer depends on changed TEXINPUTS, instead
  6004 isatool document copies the Isabelle style files to the target
  6005 location;
  6006 
  6007 
  6008 *** Isar ***
  6009 
  6010 * Pure/Provers: improved proof by cases and induction;
  6011   - 'case' command admits impromptu naming of parameters (such as
  6012     "case (Suc n)");
  6013   - 'induct' method divinates rule instantiation from the inductive
  6014     claim; no longer requires excessive ?P bindings for proper
  6015     instantiation of cases;
  6016   - 'induct' method properly enumerates all possibilities of set/type
  6017     rules; as a consequence facts may be also passed through *type*
  6018     rules without further ado;
  6019   - 'induct' method now derives symbolic cases from the *rulified*
  6020     rule (before it used to rulify cases stemming from the internal
  6021     atomized version); this means that the context of a non-atomic
  6022     statement becomes is included in the hypothesis, avoiding the
  6023     slightly cumbersome show "PROP ?case" form;
  6024   - 'induct' may now use elim-style induction rules without chaining
  6025     facts, using ``missing'' premises from the goal state; this allows
  6026     rules stemming from inductive sets to be applied in unstructured
  6027     scripts, while still benefitting from proper handling of non-atomic
  6028     statements; NB: major inductive premises need to be put first, all
  6029     the rest of the goal is passed through the induction;
  6030   - 'induct' proper support for mutual induction involving non-atomic
  6031     rule statements (uses the new concept of simultaneous goals, see
  6032     below);
  6033   - append all possible rule selections, but only use the first
  6034     success (no backtracking);
  6035   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  6036   - undeclared rule case names default to numbers 1, 2, 3, ...;
  6037   - added 'print_induct_rules' (covered by help item in recent Proof
  6038     General versions);
  6039   - moved induct/cases attributes to Pure, methods to Provers;
  6040   - generic method setup instantiated for FOL and HOL;
  6041 
  6042 * Pure: support multiple simultaneous goal statements, for example
  6043 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  6044 meta-level mechanism, this acts as if several individual goals had
  6045 been stated separately; in particular common proof methods need to be
  6046 repeated in order to cover all claims; note that a single elimination
  6047 step is *not* sufficient to establish the two conjunctions, so this
  6048 fails:
  6049 
  6050   assume "A & B" then have A and B ..   (*".." fails*)
  6051 
  6052 better use "obtain" in situations as above; alternative refer to
  6053 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  6054 
  6055 * Pure: proper integration with ``locales''; unlike the original
  6056 version by Florian Kammller, Isar locales package high-level proof
  6057 contexts rather than raw logical ones (e.g. we admit to include
  6058 attributes everywhere); operations on locales include merge and
  6059 rename; support for implicit arguments (``structures''); simultaneous
  6060 type-inference over imports and text; see also HOL/ex/Locales.thy for
  6061 some examples;
  6062 
  6063 * Pure: the following commands have been ``localized'', supporting a
  6064 target locale specification "(in name)": 'lemma', 'theorem',
  6065 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  6066 stored both within the locale and at the theory level (exported and
  6067 qualified by the locale name);
  6068 
  6069 * Pure: theory goals may now be specified in ``long'' form, with
  6070 ad-hoc contexts consisting of arbitrary locale elements. for example
  6071 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  6072 definitions may be given, too); the result is a meta-level rule with
  6073 the context elements being discharged in the obvious way;
  6074 
  6075 * Pure: new proof command 'using' allows to augment currently used
  6076 facts after a goal statement ('using' is syntactically analogous to
  6077 'apply', but acts on the goal's facts only); this allows chained facts
  6078 to be separated into parts given before and after a claim, as in
  6079 ``from a and b have C using d and e <proof>'';
  6080 
  6081 * Pure: renamed "antecedent" case to "rule_context";
  6082 
  6083 * Pure: new 'judgment' command records explicit information about the
  6084 object-logic embedding (used by several tools internally); no longer
  6085 use hard-wired "Trueprop";
  6086 
  6087 * Pure: added 'corollary' command;
  6088 
  6089 * Pure: fixed 'token_translation' command;
  6090 
  6091 * Pure: removed obsolete 'exported' attribute;
  6092 
  6093 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  6094 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  6095 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  6096 
  6097 * Pure: method 'atomize' presents local goal premises as object-level
  6098 statements (atomic meta-level propositions); setup controlled via
  6099 rewrite rules declarations of 'atomize' attribute; example
  6100 application: 'induct' method with proper rule statements in improper
  6101 proof *scripts*;
  6102 
  6103 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  6104 now consider the syntactic context of assumptions, giving a better
  6105 chance to get type-inference of the arguments right (this is
  6106 especially important for locales);
  6107 
  6108 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  6109 mode;
  6110 
  6111 * Pure/obtain: the formal conclusion "thesis", being marked as
  6112 ``internal'', may no longer be reference directly in the text;
  6113 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  6114 situations;
  6115 
  6116 * Pure: generic 'sym' attribute which declares a rule both as pure
  6117 'elim?' and for the 'symmetric' operation;
  6118 
  6119 * Pure: marginal comments ``--'' may now occur just anywhere in the
  6120 text; the fixed correlation with particular command syntax has been
  6121 discontinued;
  6122 
  6123 * Pure: new method 'rules' is particularly well-suited for proof
  6124 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  6125 but often produces more compact proof terms with less detours;
  6126 
  6127 * Pure/Provers/classical: simplified integration with pure rule
  6128 attributes and methods; the classical "intro?/elim?/dest?"
  6129 declarations coincide with the pure ones; the "rule" method no longer
  6130 includes classically swapped intros; "intro" and "elim" methods no
  6131 longer pick rules from the context; also got rid of ML declarations
  6132 AddXIs/AddXEs/AddXDs; all of this has some potential for
  6133 INCOMPATIBILITY;
  6134 
  6135 * Provers/classical: attribute 'swapped' produces classical inversions
  6136 of introduction rules;
  6137 
  6138 * Provers/simplifier: 'simplified' attribute may refer to explicit
  6139 rules instead of full simplifier context; 'iff' attribute handles
  6140 conditional rules;
  6141 
  6142 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  6143 
  6144 * HOL: 'recdef' now fails on unfinished automated proofs, use
  6145 "(permissive)" option to recover old behavior;
  6146 
  6147 * HOL: 'inductive' no longer features separate (collective) attributes
  6148 for 'intros' (was found too confusing);
  6149 
  6150 * HOL: properly declared induction rules less_induct and
  6151 wf_induct_rule;
  6152 
  6153 
  6154 *** HOL ***
  6155 
  6156 * HOL: moved over to sane numeral syntax; the new policy is as
  6157 follows:
  6158 
  6159   - 0 and 1 are polymorphic constants, which are defined on any
  6160   numeric type (nat, int, real etc.);
  6161 
  6162   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  6163   binary representation internally;
  6164 
  6165   - type nat has special constructor Suc, and generally prefers Suc 0
  6166   over 1::nat and Suc (Suc 0) over 2::nat;
  6167 
  6168 This change may cause significant problems of INCOMPATIBILITY; here
  6169 are some hints on converting existing sources:
  6170 
  6171   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  6172   entities, so expressions involving "-" (unary or binary minus) need
  6173   to be spaced properly;
  6174 
  6175   - existing occurrences of "1" may need to be constraint "1::nat" or
  6176   even replaced by Suc 0; similar for old "2";
  6177 
  6178   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  6179 
  6180   - remove all special provisions on numerals in proofs;
  6181 
  6182 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  6183 representation (depends on bin_arith_simps in the default context);
  6184 
  6185 * HOL: symbolic syntax for x^2 (numeral 2);
  6186 
  6187 * HOL: the class of all HOL types is now called "type" rather than
  6188 "term"; INCOMPATIBILITY, need to adapt references to this type class
  6189 in axclass/classes, instance/arities, and (usually rare) occurrences
  6190 in typings (of consts etc.); internally the class is called
  6191 "HOL.type", ML programs should refer to HOLogic.typeS;
  6192 
  6193 * HOL/record package improvements:
  6194   - new derived operations "fields" to build a partial record section,
  6195     "extend" to promote a fixed record to a record scheme, and
  6196     "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*
  6197     declared as simp by default;
  6198   - shared operations ("more", "fields", etc.) now need to be always
  6199     qualified) --- potential INCOMPATIBILITY;
  6200   - removed "make_scheme" operations (use "make" with "extend") --
  6201     INCOMPATIBILITY;
  6202   - removed "more" class (simply use "term") -- INCOMPATIBILITY;
  6203   - provides cases/induct rules for use with corresponding Isar
  6204     methods (for concrete records, record schemes, concrete more
  6205     parts, and schematic more parts -- in that order);
  6206   - internal definitions directly based on a light-weight abstract
  6207     theory of product types over typedef rather than datatype;
  6208 
  6209 * HOL: generic code generator for generating executable ML code from
  6210 specifications; specific support for HOL constructs such as inductive
  6211 datatypes and sets, as well as recursive functions; can be invoked
  6212 via 'generate_code' theory section;
  6213 
  6214 * HOL: canonical cases/induct rules for n-tuples (n = 3..7);
  6215 
  6216 * HOL: consolidated and renamed several theories.  In particular:
  6217         Ord.thy has been absorbed into HOL.thy
  6218         String.thy has been absorbed into List.thy
  6219 
  6220 * HOL: concrete setsum syntax "\<Sum>i:A. b" == "setsum (%i. b) A"
  6221 (beware of argument permutation!);
  6222 
  6223 * HOL: linorder_less_split superseded by linorder_cases;
  6224 
  6225 * HOL/List: "nodups" renamed to "distinct";
  6226 
  6227 * HOL: added "The" definite description operator; move Hilbert's "Eps"
  6228 to peripheral theory "Hilbert_Choice"; some INCOMPATIBILITIES:
  6229   - Ex_def has changed, now need to use some_eq_ex
  6230