NEWS
author haftmann
Sat May 14 18:26:25 2011 +0200 (2011-05-14)
changeset 42809 5b45125b15ba
parent 42793 88bee9f6eec7
child 42815 61668e617a3b
permissions -rw-r--r--
use pointfree characterisation for fold_set locale
     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: former unsynchronized references are now proper
    41 configuration options, with more conventional names:
    42 
    43   long_names   ~> names_long
    44   short_names  ~> names_short
    45   unique_names ~> names_unique
    46 
    47 Minor INCOMPATIBILITY, need to declare options in context like this:
    48 
    49   declare [[names_unique = false]]
    50 
    51 * Literal facts `prop` may contain dummy patterns, e.g. `_ = _`.  Note
    52 that the result needs to be unique, which means fact specifications
    53 may have to be refined after enriching a proof context.
    54 
    55 * Isabelle/Isar reference manual provides more formal references in
    56 syntax diagrams.
    57 
    58 
    59 *** HOL ***
    60 
    61 * Finite_Set.thy: locale fun_left_comm uses point-free characterisation;
    62 interpretation proofs may need adjustment.  INCOMPATIBILITY.
    63 
    64 * Nitpick:
    65   - Added "need" and "total_consts" options.
    66   - Reintroduced "show_skolems" option by popular demand.
    67   - Renamed attribute: nitpick_def ~> nitpick_unfold.
    68     INCOMPATIBILITY.
    69 
    70 * Sledgehammer:
    71   - sledgehammer available_provers ~> sledgehammer supported_provers
    72     INCOMPATIBILITY.
    73   - Added support for SNARK and ToFoF-E on SystemOnTPTP and for simply typed
    74     TPTP problems (TFF).
    75   - Added "type_sys", "max_mono_iters", and "max_new_mono_instances" options.
    76 
    77 * "try":
    78   - Added "simp:", "intro:", and "elim:" options.
    79 
    80 * Quickcheck:
    81   - Added "eval" option to evaluate terms for the found counterexample
    82     (currently only supported by the default (exhaustive) tester)
    83   - Added post-processing of terms to obtain readable counterexamples
    84     (currently only supported by the default (exhaustive) tester)
    85 
    86 * Function package: discontinued option "tailrec".
    87 INCOMPATIBILITY. Use partial_function instead.
    88 
    89 * HOL-Probability:
    90   - Caratheodory's extension lemma is now proved for ring_of_sets.
    91   - Infinite products of probability measures are now available.
    92   - Use extended reals instead of positive extended reals.
    93     INCOMPATIBILITY.
    94 
    95 
    96 *** Document preparation ***
    97 
    98 * Antiquotation @{rail} layouts railroad syntax diagrams, see also
    99 isar-ref manual.
   100 
   101 * Localized \isabellestyle switch can be used within blocks or groups
   102 like this:
   103 
   104   \isabellestyle{it}  %preferred default
   105   {\isabellestylett @{text "typewriter stuff"}}
   106 
   107 * New term style "isub" as ad-hoc conversion of variables x1, y23 into
   108 subscripted form x\<^isub>1, y\<^isub>2\<^isub>3.
   109 
   110 * Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
   111 (e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).
   112 
   113 
   114 *** ML ***
   115 
   116 * Structure Proof_Context follows standard naming scheme.  Old
   117 ProofContext is still available for some time as legacy alias.
   118 
   119 * Structure Timing provides various operations for timing; supersedes
   120 former start_timing/end_timing etc.
   121 
   122 * Path.print is the official way to show file-system paths to users
   123 (including quotes etc.).
   124 
   125 * Inner syntax: identifiers in parse trees of generic categories
   126 "logic", "aprop", "idt" etc. carry position information (disguised as
   127 type constraints).  Occasional INCOMPATIBILITY with non-compliant
   128 translations that choke on unexpected type constraints.  Positions can
   129 be stripped in ML translations via Syntax.strip_positions /
   130 Syntax.strip_positions_ast, or via the syntax constant
   131 "_strip_positions" within parse trees.  As last resort, positions can
   132 be disabled via the configuration option Syntax.positions, which is
   133 called "syntax_positions" in Isar attribute syntax.
   134 
   135 * Discontinued special status of various ML structures that contribute
   136 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
   137 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
   138 refer directly to Ast.Constant, Lexicon.is_identifier,
   139 Syntax_Trans.mk_binder_tr etc.
   140 
   141 * Typed print translation: discontinued show_sorts argument, which is
   142 already available via context of "advanced" translation.
   143 
   144 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
   145 goal states; body tactic needs to address all subgoals uniformly.
   146 
   147 * Slightly more special eq_list/eq_set, with shortcut involving
   148 pointer equality (assumes that eq relation is reflexive).
   149 
   150 * Classical tactics use proper Proof.context instead of historic types
   151 claset/clasimpset.  Old-style declarations like addIs, addEs, addDs
   152 operate directly on Proof.context.  Raw type claset retains its use as
   153 snapshot of the classical context, which can be recovered via
   154 (put_claset HOL_cs) etc.  Type clasimpset has been discontinued.
   155 INCOMPATIBILITY, classical tactics and derived proof methods require
   156 proper Proof.context.
   157 
   158 
   159 
   160 New in Isabelle2011 (January 2011)
   161 ----------------------------------
   162 
   163 *** General ***
   164 
   165 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
   166 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
   167 useful tooltips and hyperlinks produced from its static analysis.  The
   168 bundled component provides an executable Isabelle tool that can be run
   169 like this:
   170 
   171   Isabelle2011/bin/isabelle jedit
   172 
   173 * Significantly improved Isabelle/Isar implementation manual.
   174 
   175 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
   176 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
   177 while the default heap location within that directory lacks that extra
   178 suffix.  This isolates multiple Isabelle installations from each
   179 other, avoiding problems with old settings in new versions.
   180 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
   181 
   182 * Source files are always encoded as UTF-8, instead of old-fashioned
   183 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
   184 the following package declarations:
   185 
   186   \usepackage[utf8]{inputenc}
   187   \usepackage{textcomp}
   188 
   189 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
   190 a Unicode character is treated as a single symbol, not a sequence of
   191 non-ASCII bytes as before.  Since Isabelle/ML string literals may
   192 contain symbols without further backslash escapes, Unicode can now be
   193 used here as well.  Recall that Symbol.explode in ML provides a
   194 consistent view on symbols, while raw explode (or String.explode)
   195 merely give a byte-oriented representation.
   196 
   197 * Theory loader: source files are primarily located via the master
   198 directory of each theory node (where the .thy file itself resides).
   199 The global load path is still partially available as legacy feature.
   200 Minor INCOMPATIBILITY due to subtle change in file lookup: use
   201 explicit paths, relatively to the theory.
   202 
   203 * Special treatment of ML file names has been discontinued.
   204 Historically, optional extensions .ML or .sml were added on demand --
   205 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
   206 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
   207 
   208 * Various options that affect pretty printing etc. are now properly
   209 handled within the context via configuration options, instead of
   210 unsynchronized references or print modes.  There are both ML Config.T
   211 entities and Isar declaration attributes to access these.
   212 
   213   ML (Config.T)                 Isar (attribute)
   214 
   215   eta_contract                  eta_contract
   216   show_brackets                 show_brackets
   217   show_sorts                    show_sorts
   218   show_types                    show_types
   219   show_question_marks           show_question_marks
   220   show_consts                   show_consts
   221   show_abbrevs                  show_abbrevs
   222 
   223   Syntax.ast_trace              syntax_ast_trace
   224   Syntax.ast_stat               syntax_ast_stat
   225   Syntax.ambiguity_level        syntax_ambiguity_level
   226 
   227   Goal_Display.goals_limit      goals_limit
   228   Goal_Display.show_main_goal   show_main_goal
   229 
   230   Method.rule_trace             rule_trace
   231 
   232   Thy_Output.display            thy_output_display
   233   Thy_Output.quotes             thy_output_quotes
   234   Thy_Output.indent             thy_output_indent
   235   Thy_Output.source             thy_output_source
   236   Thy_Output.break              thy_output_break
   237 
   238 Note that corresponding "..._default" references in ML may only be
   239 changed globally at the ROOT session setup, but *not* within a theory.
   240 The option "show_abbrevs" supersedes the former print mode
   241 "no_abbrevs" with inverted meaning.
   242 
   243 * More systematic naming of some configuration options.
   244 INCOMPATIBILITY.
   245 
   246   trace_simp  ~>  simp_trace
   247   debug_simp  ~>  simp_debug
   248 
   249 * Support for real valued configuration options, using simplistic
   250 floating-point notation that coincides with the inner syntax for
   251 float_token.
   252 
   253 * Support for real valued preferences (with approximative PGIP type):
   254 front-ends need to accept "pgint" values in float notation.
   255 INCOMPATIBILITY.
   256 
   257 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
   258 DejaVu Sans.
   259 
   260 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   261 
   262 
   263 *** Pure ***
   264 
   265 * Command 'type_synonym' (with single argument) replaces somewhat
   266 outdated 'types', which is still available as legacy feature for some
   267 time.
   268 
   269 * Command 'nonterminal' (with 'and' separated list of arguments)
   270 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
   271 
   272 * Command 'notepad' replaces former 'example_proof' for
   273 experimentation in Isar without any result.  INCOMPATIBILITY.
   274 
   275 * Locale interpretation commands 'interpret' and 'sublocale' accept
   276 lists of equations to map definitions in a locale to appropriate
   277 entities in the context of the interpretation.  The 'interpretation'
   278 command already provided this functionality.
   279 
   280 * Diagnostic command 'print_dependencies' prints the locale instances
   281 that would be activated if the specified expression was interpreted in
   282 the current context.  Variant "print_dependencies!" assumes a context
   283 without interpretations.
   284 
   285 * Diagnostic command 'print_interps' prints interpretations in proofs
   286 in addition to interpretations in theories.
   287 
   288 * Discontinued obsolete 'global' and 'local' commands to manipulate
   289 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
   290 Sign.root_path and Sign.local_path may be applied directly where this
   291 feature is still required for historical reasons.
   292 
   293 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
   294 'definition' instead.
   295 
   296 * The "prems" fact, which refers to the accidental collection of
   297 foundational premises in the context, is now explicitly marked as
   298 legacy feature and will be discontinued soon.  Consider using "assms"
   299 of the head statement or reference facts by explicit names.
   300 
   301 * Document antiquotations @{class} and @{type} print classes and type
   302 constructors.
   303 
   304 * Document antiquotation @{file} checks file/directory entries within
   305 the local file system.
   306 
   307 
   308 *** HOL ***
   309 
   310 * Coercive subtyping: functions can be declared as coercions and type
   311 inference will add them as necessary upon input of a term.  Theory
   312 Complex_Main declares real :: nat => real and real :: int => real as
   313 coercions. A coercion function f is declared like this:
   314 
   315   declare [[coercion f]]
   316 
   317 To lift coercions through type constructors (e.g. from nat => real to
   318 nat list => real list), map functions can be declared, e.g.
   319 
   320   declare [[coercion_map map]]
   321 
   322 Currently coercion inference is activated only in theories including
   323 real numbers, i.e. descendants of Complex_Main.  This is controlled by
   324 the configuration option "coercion_enabled", e.g. it can be enabled in
   325 other theories like this:
   326 
   327   declare [[coercion_enabled]]
   328 
   329 * Command 'partial_function' provides basic support for recursive
   330 function definitions over complete partial orders.  Concrete instances
   331 are provided for i) the option type, ii) tail recursion on arbitrary
   332 types, and iii) the heap monad of Imperative_HOL.  See
   333 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
   334 for examples.
   335 
   336 * Function package: f.psimps rules are no longer implicitly declared
   337 as [simp].  INCOMPATIBILITY.
   338 
   339 * Datatype package: theorems generated for executable equality (class
   340 "eq") carry proper names and are treated as default code equations.
   341 
   342 * Inductive package: now offers command 'inductive_simps' to
   343 automatically derive instantiated and simplified equations for
   344 inductive predicates, similar to 'inductive_cases'.
   345 
   346 * Command 'enriched_type' allows to register properties of the
   347 functorial structure of types.
   348 
   349 * Improved infrastructure for term evaluation using code generator
   350 techniques, in particular static evaluation conversions.
   351 
   352 * Code generator: Scala (2.8 or higher) has been added to the target
   353 languages.
   354 
   355 * Code generator: globbing constant expressions "*" and "Theory.*"
   356 have been replaced by the more idiomatic "_" and "Theory._".
   357 INCOMPATIBILITY.
   358 
   359 * Code generator: export_code without explicit file declaration prints
   360 to standard output.  INCOMPATIBILITY.
   361 
   362 * Code generator: do not print function definitions for case
   363 combinators any longer.
   364 
   365 * Code generator: simplification with rules determined with
   366 src/Tools/Code/code_simp.ML and method "code_simp".
   367 
   368 * Code generator for records: more idiomatic representation of record
   369 types.  Warning: records are not covered by ancient SML code
   370 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
   371 rep_datatype declaration helps to succeed then:
   372 
   373   record 'a foo = ...
   374   ...
   375   rep_datatype foo_ext ...
   376 
   377 * Records: logical foundation type for records does not carry a
   378 '_type' suffix any longer (obsolete due to authentic syntax).
   379 INCOMPATIBILITY.
   380 
   381 * Quickcheck now by default uses exhaustive testing instead of random
   382 testing.  Random testing can be invoked by "quickcheck [random]",
   383 exhaustive testing by "quickcheck [exhaustive]".
   384 
   385 * Quickcheck instantiates polymorphic types with small finite
   386 datatypes by default. This enables a simple execution mechanism to
   387 handle quantifiers and function equality over the finite datatypes.
   388 
   389 * Quickcheck random generator has been renamed from "code" to
   390 "random".  INCOMPATIBILITY.
   391 
   392 * Quickcheck now has a configurable time limit which is set to 30
   393 seconds by default. This can be changed by adding [timeout = n] to the
   394 quickcheck command. The time limit for Auto Quickcheck is still set
   395 independently.
   396 
   397 * Quickcheck in locales considers interpretations of that locale for
   398 counter example search.
   399 
   400 * Sledgehammer:
   401   - Added "smt" and "remote_smt" provers based on the "smt" proof
   402     method. See the Sledgehammer manual for details ("isabelle doc
   403     sledgehammer").
   404   - Renamed commands:
   405     sledgehammer atp_info ~> sledgehammer running_provers
   406     sledgehammer atp_kill ~> sledgehammer kill_provers
   407     sledgehammer available_atps ~> sledgehammer available_provers
   408     INCOMPATIBILITY.
   409   - Renamed options:
   410     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
   411     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
   412     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
   413     (and "ms" and "min" are no longer supported)
   414     INCOMPATIBILITY.
   415 
   416 * Nitpick:
   417   - Renamed options:
   418     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
   419     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
   420     INCOMPATIBILITY.
   421   - Added support for partial quotient types.
   422   - Added local versions of the "Nitpick.register_xxx" functions.
   423   - Added "whack" option.
   424   - Allow registration of quotient types as codatatypes.
   425   - Improved "merge_type_vars" option to merge more types.
   426   - Removed unsound "fast_descrs" option.
   427   - Added custom symmetry breaking for datatypes, making it possible to reach
   428     higher cardinalities.
   429   - Prevent the expansion of too large definitions.
   430 
   431 * Proof methods "metis" and "meson" now have configuration options
   432 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
   433 to diagnose these tools. E.g.
   434 
   435     using [[metis_trace = true]]
   436 
   437 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
   438 manually as command 'solve_direct'.
   439 
   440 * The default SMT solver Z3 must be enabled explicitly (due to
   441 licensing issues) by setting the environment variable
   442 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
   443 commercial applications, the SMT solver CVC3 is provided as fall-back;
   444 changing the SMT solver is done via the configuration option
   445 "smt_solver".
   446 
   447 * Remote SMT solvers need to be referred to by the "remote_" prefix,
   448 i.e. "remote_cvc3" and "remote_z3".
   449 
   450 * Added basic SMT support for datatypes, records, and typedefs using
   451 the oracle mode (no proofs).  Direct support of pairs has been dropped
   452 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
   453 support for a similar behavior).  Minor INCOMPATIBILITY.
   454 
   455 * Changed SMT configuration options:
   456   - Renamed:
   457     z3_proofs ~> smt_oracle (with inverted meaning)
   458     z3_trace_assms ~> smt_trace_used_facts
   459     INCOMPATIBILITY.
   460   - Added:
   461     smt_verbose
   462     smt_random_seed
   463     smt_datatypes
   464     smt_infer_triggers
   465     smt_monomorph_limit
   466     cvc3_options
   467     remote_cvc3_options
   468     remote_z3_options
   469     yices_options
   470 
   471 * Boogie output files (.b2i files) need to be declared in the theory
   472 header.
   473 
   474 * Simplification procedure "list_to_set_comprehension" rewrites list
   475 comprehensions applied to List.set to set comprehensions.  Occasional
   476 INCOMPATIBILITY, may be deactivated like this:
   477 
   478   declare [[simproc del: list_to_set_comprehension]]
   479 
   480 * Removed old version of primrec package.  INCOMPATIBILITY.
   481 
   482 * Removed simplifier congruence rule of "prod_case", as has for long
   483 been the case with "split".  INCOMPATIBILITY.
   484 
   485 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
   486 
   487 * Removed [split_format ... and ... and ...] version of
   488 [split_format].  Potential INCOMPATIBILITY.
   489 
   490 * Predicate "sorted" now defined inductively, with nice induction
   491 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
   492 
   493 * Constant "contents" renamed to "the_elem", to free the generic name
   494 contents for other uses.  INCOMPATIBILITY.
   495 
   496 * Renamed class eq and constant eq (for code generation) to class
   497 equal and constant equal, plus renaming of related facts and various
   498 tuning.  INCOMPATIBILITY.
   499 
   500 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
   501 
   502 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
   503 INCOMPATIBILITY.
   504 
   505 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
   506 avoid confusion with finite sets.  INCOMPATIBILITY.
   507 
   508 * Abandoned locales equiv, congruent and congruent2 for equivalence
   509 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
   510 for congruent(2)).
   511 
   512 * Some previously unqualified names have been qualified:
   513 
   514   types
   515     bool ~> HOL.bool
   516     nat ~> Nat.nat
   517 
   518   constants
   519     Trueprop ~> HOL.Trueprop
   520     True ~> HOL.True
   521     False ~> HOL.False
   522     op & ~> HOL.conj
   523     op | ~> HOL.disj
   524     op --> ~> HOL.implies
   525     op = ~> HOL.eq
   526     Not ~> HOL.Not
   527     The ~> HOL.The
   528     All ~> HOL.All
   529     Ex ~> HOL.Ex
   530     Ex1 ~> HOL.Ex1
   531     Let ~> HOL.Let
   532     If ~> HOL.If
   533     Ball ~> Set.Ball
   534     Bex ~> Set.Bex
   535     Suc ~> Nat.Suc
   536     Pair ~> Product_Type.Pair
   537     fst ~> Product_Type.fst
   538     snd ~> Product_Type.snd
   539     curry ~> Product_Type.curry
   540     op : ~> Set.member
   541     Collect ~> Set.Collect
   542 
   543 INCOMPATIBILITY.
   544 
   545 * More canonical naming convention for some fundamental definitions:
   546 
   547     bot_bool_eq ~> bot_bool_def
   548     top_bool_eq ~> top_bool_def
   549     inf_bool_eq ~> inf_bool_def
   550     sup_bool_eq ~> sup_bool_def
   551     bot_fun_eq  ~> bot_fun_def
   552     top_fun_eq  ~> top_fun_def
   553     inf_fun_eq  ~> inf_fun_def
   554     sup_fun_eq  ~> sup_fun_def
   555 
   556 INCOMPATIBILITY.
   557 
   558 * More stylized fact names:
   559 
   560   expand_fun_eq ~> fun_eq_iff
   561   expand_set_eq ~> set_eq_iff
   562   set_ext       ~> set_eqI
   563   nat_number    ~> eval_nat_numeral
   564 
   565 INCOMPATIBILITY.
   566 
   567 * Refactoring of code-generation specific operations in theory List:
   568 
   569   constants
   570     null ~> List.null
   571 
   572   facts
   573     mem_iff ~> member_def
   574     null_empty ~> null_def
   575 
   576 INCOMPATIBILITY.  Note that these were not supposed to be used
   577 regularly unless for striking reasons; their main purpose was code
   578 generation.
   579 
   580 Various operations from the Haskell prelude are used for generating
   581 Haskell code.
   582 
   583 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
   584 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
   585 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
   586 
   587 * Abolished some non-alphabetic type names: "prod" and "sum" replace
   588 "*" and "+" respectively.  INCOMPATIBILITY.
   589 
   590 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
   591 "Sum_Type.Plus" instead.
   592 
   593 * Constant "split" has been merged with constant "prod_case"; names of
   594 ML functions, facts etc. involving split have been retained so far,
   595 though.  INCOMPATIBILITY.
   596 
   597 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
   598 instead.  INCOMPATIBILITY.
   599 
   600 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
   601 INCOMPATIBILITY.
   602 
   603 * Former theory Library/Enum is now part of the HOL-Main image.
   604 INCOMPATIBILITY: all constants of the Enum theory now have to be
   605 referred to by its qualified name.
   606 
   607   enum    ~>  Enum.enum
   608   nlists  ~>  Enum.nlists
   609   product ~>  Enum.product
   610 
   611 * Theory Library/Monad_Syntax provides do-syntax for monad types.
   612 Syntax in Library/State_Monad has been changed to avoid ambiguities.
   613 INCOMPATIBILITY.
   614 
   615 * Theory Library/SetsAndFunctions has been split into
   616 Library/Function_Algebras and Library/Set_Algebras; canonical names
   617 for instance definitions for functions; various improvements.
   618 INCOMPATIBILITY.
   619 
   620 * Theory Library/Multiset provides stable quicksort implementation of
   621 sort_key.
   622 
   623 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
   624 INCOMPATIBILITY.
   625 
   626 * Session Multivariate_Analysis: introduced a type class for euclidean
   627 space.  Most theorems are now stated in terms of euclidean spaces
   628 instead of finite cartesian products.
   629 
   630   types
   631     real ^ 'n ~>  'a::real_vector
   632               ~>  'a::euclidean_space
   633               ~>  'a::ordered_euclidean_space
   634         (depends on your needs)
   635 
   636   constants
   637      _ $ _        ~> _ $$ _
   638      \<chi> x. _  ~> \<chi>\<chi> x. _
   639      CARD('n)     ~> DIM('a)
   640 
   641 Also note that the indices are now natural numbers and not from some
   642 finite type. Finite cartesian products of euclidean spaces, products
   643 of euclidean spaces the real and complex numbers are instantiated to
   644 be euclidean_spaces.  INCOMPATIBILITY.
   645 
   646 * Session Probability: introduced pextreal as positive extended real
   647 numbers.  Use pextreal as value for measures.  Introduce the
   648 Radon-Nikodym derivative, product spaces and Fubini's theorem for
   649 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
   650 the integral in Multivariate Analysis.  INCOMPATIBILITY.
   651 
   652 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   653 INCOMPATIBILITY.
   654 
   655 * Session SPARK (with image HOL-SPARK) provides commands to load and
   656 prove verification conditions generated by the SPARK Ada program
   657 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
   658 
   659 
   660 *** HOL-Algebra ***
   661 
   662 * Theorems for additive ring operations (locale abelian_monoid and
   663 descendants) are generated by interpretation from their multiplicative
   664 counterparts.  Names (in particular theorem names) have the mandatory
   665 qualifier 'add'.  Previous theorem names are redeclared for
   666 compatibility.
   667 
   668 * Structure "int_ring" is now an abbreviation (previously a
   669 definition).  This fits more natural with advanced interpretations.
   670 
   671 
   672 *** HOLCF ***
   673 
   674 * The domain package now runs in definitional mode by default: The
   675 former command 'new_domain' is now called 'domain'.  To use the domain
   676 package in its original axiomatic mode, use 'domain (unsafe)'.
   677 INCOMPATIBILITY.
   678 
   679 * The new class "domain" is now the default sort.  Class "predomain"
   680 is an unpointed version of "domain". Theories can be updated by
   681 replacing sort annotations as shown below.  INCOMPATIBILITY.
   682 
   683   'a::type ~> 'a::countable
   684   'a::cpo  ~> 'a::predomain
   685   'a::pcpo ~> 'a::domain
   686 
   687 * The old type class "rep" has been superseded by class "domain".
   688 Accordingly, users of the definitional package must remove any
   689 "default_sort rep" declarations.  INCOMPATIBILITY.
   690 
   691 * The domain package (definitional mode) now supports unpointed
   692 predomain argument types, as long as they are marked 'lazy'. (Strict
   693 arguments must be in class "domain".) For example, the following
   694 domain definition now works:
   695 
   696   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
   697 
   698 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
   699 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
   700 'a option, and 'a list.  Additionally, it configures fixrec and the
   701 domain package to work with these types.  For example:
   702 
   703   fixrec isInl :: "('a + 'b) u -> tr"
   704     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
   705 
   706   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
   707 
   708 * The "(permissive)" option of fixrec has been replaced with a
   709 per-equation "(unchecked)" option. See
   710 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
   711 
   712 * The "bifinite" class no longer fixes a constant "approx"; the class
   713 now just asserts that such a function exists.  INCOMPATIBILITY.
   714 
   715 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
   716 defines an embedding of type 'a defl into udom by default; instances
   717 of "bifinite" and "domain" classes are available in
   718 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
   719 
   720 * The syntax "REP('a)" has been replaced with "DEFL('a)".
   721 
   722 * The predicate "directed" has been removed.  INCOMPATIBILITY.
   723 
   724 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
   725 
   726 * The function "cprod_map" has been renamed to "prod_map".
   727 INCOMPATIBILITY.
   728 
   729 * The monadic bind operator on each powerdomain has new binder syntax
   730 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
   731 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
   732 
   733 * The infix syntax for binary union on each powerdomain has changed
   734 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
   735 syntax.  INCOMPATIBILITY.
   736 
   737 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
   738 still supported as an input translation.
   739 
   740 * Renamed some theorems (the original names are also still available).
   741 
   742   expand_fun_below   ~> fun_below_iff
   743   below_fun_ext      ~> fun_belowI
   744   expand_cfun_eq     ~> cfun_eq_iff
   745   ext_cfun           ~> cfun_eqI
   746   expand_cfun_below  ~> cfun_below_iff
   747   below_cfun_ext     ~> cfun_belowI
   748   cont2cont_Rep_CFun ~> cont2cont_APP
   749 
   750 * The Abs and Rep functions for various types have changed names.
   751 Related theorem names have also changed to match. INCOMPATIBILITY.
   752 
   753   Rep_CFun  ~> Rep_cfun
   754   Abs_CFun  ~> Abs_cfun
   755   Rep_Sprod ~> Rep_sprod
   756   Abs_Sprod ~> Abs_sprod
   757   Rep_Ssum  ~> Rep_ssum
   758   Abs_Ssum  ~> Abs_ssum
   759 
   760 * Lemmas with names of the form *_defined_iff or *_strict_iff have
   761 been renamed to *_bottom_iff.  INCOMPATIBILITY.
   762 
   763 * Various changes to bisimulation/coinduction with domain package:
   764 
   765   - Definitions of "bisim" constants no longer mention definedness.
   766   - With mutual recursion, "bisim" predicate is now curried.
   767   - With mutual recursion, each type gets a separate coind theorem.
   768   - Variable names in bisim_def and coinduct rules have changed.
   769 
   770 INCOMPATIBILITY.
   771 
   772 * Case combinators generated by the domain package for type "foo" are
   773 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
   774 
   775 * Several theorems have been renamed to more accurately reflect the
   776 names of constants and types involved.  INCOMPATIBILITY.
   777 
   778   thelub_const    ~> lub_const
   779   lub_const       ~> is_lub_const
   780   thelubI         ~> lub_eqI
   781   is_lub_lub      ~> is_lubD2
   782   lubI            ~> is_lub_lub
   783   unique_lub      ~> is_lub_unique
   784   is_ub_lub       ~> is_lub_rangeD1
   785   lub_bin_chain   ~> is_lub_bin_chain
   786   lub_fun         ~> is_lub_fun
   787   thelub_fun      ~> lub_fun
   788   thelub_cfun     ~> lub_cfun
   789   thelub_Pair     ~> lub_Pair
   790   lub_cprod       ~> is_lub_prod
   791   thelub_cprod    ~> lub_prod
   792   minimal_cprod   ~> minimal_prod
   793   inst_cprod_pcpo ~> inst_prod_pcpo
   794   UU_I            ~> bottomI
   795   compact_UU      ~> compact_bottom
   796   deflation_UU    ~> deflation_bottom
   797   finite_deflation_UU ~> finite_deflation_bottom
   798 
   799 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
   800 
   801   sq_ord_less_eq_trans ~> below_eq_trans
   802   sq_ord_eq_less_trans ~> eq_below_trans
   803   refl_less            ~> below_refl
   804   trans_less           ~> below_trans
   805   antisym_less         ~> below_antisym
   806   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
   807   box_less             ~> box_below
   808   rev_trans_less       ~> rev_below_trans
   809   not_less2not_eq      ~> not_below2not_eq
   810   less_UU_iff          ~> below_UU_iff
   811   flat_less_iff        ~> flat_below_iff
   812   adm_less             ~> adm_below
   813   adm_not_less         ~> adm_not_below
   814   adm_compact_not_less ~> adm_compact_not_below
   815   less_fun_def         ~> below_fun_def
   816   expand_fun_less      ~> fun_below_iff
   817   less_fun_ext         ~> fun_belowI
   818   less_discr_def       ~> below_discr_def
   819   discr_less_eq        ~> discr_below_eq
   820   less_unit_def        ~> below_unit_def
   821   less_cprod_def       ~> below_prod_def
   822   prod_lessI           ~> prod_belowI
   823   Pair_less_iff        ~> Pair_below_iff
   824   fst_less_iff         ~> fst_below_iff
   825   snd_less_iff         ~> snd_below_iff
   826   expand_cfun_less     ~> cfun_below_iff
   827   less_cfun_ext        ~> cfun_belowI
   828   injection_less       ~> injection_below
   829   less_up_def          ~> below_up_def
   830   not_Iup_less         ~> not_Iup_below
   831   Iup_less             ~> Iup_below
   832   up_less              ~> up_below
   833   Def_inject_less_eq   ~> Def_below_Def
   834   Def_less_is_eq       ~> Def_below_iff
   835   spair_less_iff       ~> spair_below_iff
   836   less_sprod           ~> below_sprod
   837   spair_less           ~> spair_below
   838   sfst_less_iff        ~> sfst_below_iff
   839   ssnd_less_iff        ~> ssnd_below_iff
   840   fix_least_less       ~> fix_least_below
   841   dist_less_one        ~> dist_below_one
   842   less_ONE             ~> below_ONE
   843   ONE_less_iff         ~> ONE_below_iff
   844   less_sinlD           ~> below_sinlD
   845   less_sinrD           ~> below_sinrD
   846 
   847 
   848 *** FOL and ZF ***
   849 
   850 * All constant names are now qualified internally and use proper
   851 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
   852 
   853 
   854 *** ML ***
   855 
   856 * Antiquotation @{assert} inlines a function bool -> unit that raises
   857 Fail if the argument is false.  Due to inlining the source position of
   858 failed assertions is included in the error output.
   859 
   860 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
   861 text is in practice always evaluated with a stable theory checkpoint.
   862 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
   863 
   864 * Antiquotation @{theory A} refers to theory A from the ancestry of
   865 the current context, not any accidental theory loader state as before.
   866 Potential INCOMPATIBILITY, subtle change in semantics.
   867 
   868 * Syntax.pretty_priority (default 0) configures the required priority
   869 of pretty-printed output and thus affects insertion of parentheses.
   870 
   871 * Syntax.default_root (default "any") configures the inner syntax
   872 category (nonterminal symbol) for parsing of terms.
   873 
   874 * Former exception Library.UnequalLengths now coincides with
   875 ListPair.UnequalLengths.
   876 
   877 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
   878 main functionality is provided by structure Simplifier.
   879 
   880 * Renamed raw "explode" function to "raw_explode" to emphasize its
   881 meaning.  Note that internally to Isabelle, Symbol.explode is used in
   882 almost all situations.
   883 
   884 * Discontinued obsolete function sys_error and exception SYS_ERROR.
   885 See implementation manual for further details on exceptions in
   886 Isabelle/ML.
   887 
   888 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
   889 meaning.
   890 
   891 * Renamed structure PureThy to Pure_Thy and moved most of its
   892 operations to structure Global_Theory, to emphasize that this is
   893 rarely-used global-only stuff.
   894 
   895 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
   896 instead (or tracing for high-volume output).
   897 
   898 * Configuration option show_question_marks only affects regular pretty
   899 printing of types and terms, not raw Term.string_of_vname.
   900 
   901 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
   902 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
   903 @{thms} for most purposes.
   904 
   905 * ML structure Unsynchronized is never opened, not even in Isar
   906 interaction mode as before.  Old Unsynchronized.set etc. have been
   907 discontinued -- use plain := instead.  This should be *rare* anyway,
   908 since modern tools always work via official context data, notably
   909 configuration options.
   910 
   911 * Parallel and asynchronous execution requires special care concerning
   912 interrupts.  Structure Exn provides some convenience functions that
   913 avoid working directly with raw Interrupt.  User code must not absorb
   914 interrupts -- intermediate handling (for cleanup etc.) needs to be
   915 followed by re-raising of the original exception.  Another common
   916 source of mistakes are "handle _" patterns, which make the meaning of
   917 the program subject to physical effects of the environment.
   918 
   919 
   920 
   921 New in Isabelle2009-2 (June 2010)
   922 ---------------------------------
   923 
   924 *** General ***
   925 
   926 * Authentic syntax for *all* logical entities (type classes, type
   927 constructors, term constants): provides simple and robust
   928 correspondence between formal entities and concrete syntax.  Within
   929 the parse tree / AST representations, "constants" are decorated by
   930 their category (class, type, const) and spelled out explicitly with
   931 their full internal name.
   932 
   933 Substantial INCOMPATIBILITY concerning low-level syntax declarations
   934 and translations (translation rules and translation functions in ML).
   935 Some hints on upgrading:
   936 
   937   - Many existing uses of 'syntax' and 'translations' can be replaced
   938     by more modern 'type_notation', 'notation' and 'abbreviation',
   939     which are independent of this issue.
   940 
   941   - 'translations' require markup within the AST; the term syntax
   942     provides the following special forms:
   943 
   944       CONST c   -- produces syntax version of constant c from context
   945       XCONST c  -- literally c, checked as constant from context
   946       c         -- literally c, if declared by 'syntax'
   947 
   948     Plain identifiers are treated as AST variables -- occasionally the
   949     system indicates accidental variables via the error "rhs contains
   950     extra variables".
   951 
   952     Type classes and type constructors are marked according to their
   953     concrete syntax.  Some old translations rules need to be written
   954     for the "type" category, using type constructor application
   955     instead of pseudo-term application of the default category
   956     "logic".
   957 
   958   - 'parse_translation' etc. in ML may use the following
   959     antiquotations:
   960 
   961       @{class_syntax c}   -- type class c within parse tree / AST
   962       @{term_syntax c}    -- type constructor c within parse tree / AST
   963       @{const_syntax c}   -- ML version of "CONST c" above
   964       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
   965 
   966   - Literal types within 'typed_print_translations', i.e. those *not*
   967     represented as pseudo-terms are represented verbatim.  Use @{class
   968     c} or @{type_name c} here instead of the above syntax
   969     antiquotations.
   970 
   971 Note that old non-authentic syntax was based on unqualified base
   972 names, so all of the above "constant" names would coincide.  Recall
   973 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
   974 diagnose syntax problems.
   975 
   976 * Type constructors admit general mixfix syntax, not just infix.
   977 
   978 * Concrete syntax may be attached to local entities without a proof
   979 body, too.  This works via regular mixfix annotations for 'fix',
   980 'def', 'obtain' etc. or via the explicit 'write' command, which is
   981 similar to the 'notation' command in theory specifications.
   982 
   983 * Discontinued unnamed infix syntax (legacy feature for many years) --
   984 need to specify constant name and syntax separately.  Internal ML
   985 datatype constructors have been renamed from InfixName to Infix etc.
   986 Minor INCOMPATIBILITY.
   987 
   988 * Schematic theorem statements need to be explicitly markup as such,
   989 via commands 'schematic_lemma', 'schematic_theorem',
   990 'schematic_corollary'.  Thus the relevance of the proof is made
   991 syntactically clear, which impacts performance in a parallel or
   992 asynchronous interactive environment.  Minor INCOMPATIBILITY.
   993 
   994 * Use of cumulative prems via "!" in some proof methods has been
   995 discontinued (old legacy feature).
   996 
   997 * References 'trace_simp' and 'debug_simp' have been replaced by
   998 configuration options stored in the context. Enabling tracing (the
   999 case of debugging is similar) in proofs works via
  1000 
  1001   using [[trace_simp = true]]
  1002 
  1003 Tracing is then active for all invocations of the simplifier in
  1004 subsequent goal refinement steps. Tracing may also still be enabled or
  1005 disabled via the ProofGeneral settings menu.
  1006 
  1007 * Separate commands 'hide_class', 'hide_type', 'hide_const',
  1008 'hide_fact' replace the former 'hide' KIND command.  Minor
  1009 INCOMPATIBILITY.
  1010 
  1011 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
  1012 more efficient than combinations with -q1 or -q2.
  1013 
  1014 
  1015 *** Pure ***
  1016 
  1017 * Proofterms record type-class reasoning explicitly, using the
  1018 "unconstrain" operation internally.  This eliminates all sort
  1019 constraints from a theorem and proof, introducing explicit
  1020 OFCLASS-premises.  On the proof term level, this operation is
  1021 automatically applied at theorem boundaries, such that closed proofs
  1022 are always free of sort constraints.  INCOMPATIBILITY for tools that
  1023 inspect proof terms.
  1024 
  1025 * Local theory specifications may depend on extra type variables that
  1026 are not present in the result type -- arguments TYPE('a) :: 'a itself
  1027 are added internally.  For example:
  1028 
  1029   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
  1030 
  1031 * Predicates of locales introduced by classes carry a mandatory
  1032 "class" prefix.  INCOMPATIBILITY.
  1033 
  1034 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
  1035 
  1036 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
  1037 'class' instead.
  1038 
  1039 * Command 'code_reflect' allows to incorporate generated ML code into
  1040 runtime environment; replaces immature code_datatype antiquotation.
  1041 INCOMPATIBILITY.
  1042 
  1043 * Code generator: simple concept for abstract datatypes obeying
  1044 invariants.
  1045 
  1046 * Code generator: details of internal data cache have no impact on the
  1047 user space functionality any longer.
  1048 
  1049 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  1050 subgoals.  This is more appropriate for interpretations with 'where'.
  1051 INCOMPATIBILITY.
  1052 
  1053 * Command 'example_proof' opens an empty proof body.  This allows to
  1054 experiment with Isar, without producing any persistent result.
  1055 
  1056 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  1057 within a local theory context, with explicit checking of the
  1058 constructors involved (in contrast to the raw 'syntax' versions).
  1059 
  1060 * Commands 'types' and 'typedecl' now work within a local theory
  1061 context -- without introducing dependencies on parameters or
  1062 assumptions, which is not possible in Isabelle/Pure.
  1063 
  1064 * Command 'defaultsort' has been renamed to 'default_sort', it works
  1065 within a local theory context.  Minor INCOMPATIBILITY.
  1066 
  1067 
  1068 *** HOL ***
  1069 
  1070 * Command 'typedef' now works within a local theory context -- without
  1071 introducing dependencies on parameters or assumptions, which is not
  1072 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  1073 contain multiple interpretations of local typedefs (with different
  1074 non-emptiness proofs), even in a global theory context.
  1075 
  1076 * New package for quotient types.  Commands 'quotient_type' and
  1077 'quotient_definition' may be used for defining types and constants by
  1078 quotient constructions.  An example is the type of integers created by
  1079 quotienting pairs of natural numbers:
  1080 
  1081   fun
  1082     intrel :: "(nat * nat) => (nat * nat) => bool"
  1083   where
  1084     "intrel (x, y) (u, v) = (x + v = u + y)"
  1085 
  1086   quotient_type int = "nat * nat" / intrel
  1087     by (auto simp add: equivp_def expand_fun_eq)
  1088 
  1089   quotient_definition
  1090     "0::int" is "(0::nat, 0::nat)"
  1091 
  1092 The method "lifting" can be used to lift of theorems from the
  1093 underlying "raw" type to the quotient type.  The example
  1094 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  1095 construction and provides a reasoning infrastructure for finite sets.
  1096 
  1097 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  1098 clash with new theory Quotient in Main HOL.
  1099 
  1100 * Moved the SMT binding into the main HOL session, eliminating
  1101 separate HOL-SMT session.
  1102 
  1103 * List membership infix mem operation is only an input abbreviation.
  1104 INCOMPATIBILITY.
  1105 
  1106 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  1107 for future developements; former Library/Word.thy is still present in
  1108 the AFP entry RSAPPS.
  1109 
  1110 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  1111 longer shadowed.  INCOMPATIBILITY.
  1112 
  1113 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  1114 INCOMPATIBILITY.
  1115 
  1116 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  1117 INCOMPATIBILITY.
  1118 
  1119 * Dropped normalizing_semiring etc; use the facts in semiring classes
  1120 instead.  INCOMPATIBILITY.
  1121 
  1122 * Dropped several real-specific versions of lemmas about floor and
  1123 ceiling; use the generic lemmas from theory "Archimedean_Field"
  1124 instead.  INCOMPATIBILITY.
  1125 
  1126   floor_number_of_eq         ~> floor_number_of
  1127   le_floor_eq_number_of      ~> number_of_le_floor
  1128   le_floor_eq_zero           ~> zero_le_floor
  1129   le_floor_eq_one            ~> one_le_floor
  1130   floor_less_eq_number_of    ~> floor_less_number_of
  1131   floor_less_eq_zero         ~> floor_less_zero
  1132   floor_less_eq_one          ~> floor_less_one
  1133   less_floor_eq_number_of    ~> number_of_less_floor
  1134   less_floor_eq_zero         ~> zero_less_floor
  1135   less_floor_eq_one          ~> one_less_floor
  1136   floor_le_eq_number_of      ~> floor_le_number_of
  1137   floor_le_eq_zero           ~> floor_le_zero
  1138   floor_le_eq_one            ~> floor_le_one
  1139   floor_subtract_number_of   ~> floor_diff_number_of
  1140   floor_subtract_one         ~> floor_diff_one
  1141   ceiling_number_of_eq       ~> ceiling_number_of
  1142   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  1143   ceiling_le_zero_eq         ~> ceiling_le_zero
  1144   ceiling_le_eq_one          ~> ceiling_le_one
  1145   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  1146   less_ceiling_eq_zero       ~> zero_less_ceiling
  1147   less_ceiling_eq_one        ~> one_less_ceiling
  1148   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  1149   ceiling_less_eq_zero       ~> ceiling_less_zero
  1150   ceiling_less_eq_one        ~> ceiling_less_one
  1151   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  1152   le_ceiling_eq_zero         ~> zero_le_ceiling
  1153   le_ceiling_eq_one          ~> one_le_ceiling
  1154   ceiling_subtract_number_of ~> ceiling_diff_number_of
  1155   ceiling_subtract_one       ~> ceiling_diff_one
  1156 
  1157 * Theory "Finite_Set": various folding_XXX locales facilitate the
  1158 application of the various fold combinators on finite sets.
  1159 
  1160 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  1161 provides abstract red-black tree type which is backed by "RBT_Impl" as
  1162 implementation.  INCOMPATIBILTY.
  1163 
  1164 * Theory Library/Coinductive_List has been removed -- superseded by
  1165 AFP/thys/Coinductive.
  1166 
  1167 * Theory PReal, including the type "preal" and related operations, has
  1168 been removed.  INCOMPATIBILITY.
  1169 
  1170 * Real: new development using Cauchy Sequences.
  1171 
  1172 * Split off theory "Big_Operators" containing setsum, setprod,
  1173 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  1174 
  1175 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  1176 "Int" etc.  INCOMPATIBILITY.
  1177 
  1178 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  1179 
  1180 * New set of rules "ac_simps" provides combined assoc / commute
  1181 rewrites for all interpretations of the appropriate generic locales.
  1182 
  1183 * Renamed theory "OrderedGroup" to "Groups" and split theory
  1184 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  1185 appropriate and more consistent names suitable for name prefixes
  1186 within the HOL theories.  INCOMPATIBILITY.
  1187 
  1188 * Some generic constants have been put to appropriate theories:
  1189   - less_eq, less: Orderings
  1190   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  1191   - inverse, divide: Rings
  1192 INCOMPATIBILITY.
  1193 
  1194 * More consistent naming of type classes involving orderings (and
  1195 lattices):
  1196 
  1197     lower_semilattice                   ~> semilattice_inf
  1198     upper_semilattice                   ~> semilattice_sup
  1199 
  1200     dense_linear_order                  ~> dense_linorder
  1201 
  1202     pordered_ab_group_add               ~> ordered_ab_group_add
  1203     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  1204     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  1205     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  1206     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  1207     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  1208     pordered_cancel_semiring            ~> ordered_cancel_semiring
  1209     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  1210     pordered_comm_ring                  ~> ordered_comm_ring
  1211     pordered_comm_semiring              ~> ordered_comm_semiring
  1212     pordered_ring                       ~> ordered_ring
  1213     pordered_ring_abs                   ~> ordered_ring_abs
  1214     pordered_semiring                   ~> ordered_semiring
  1215 
  1216     ordered_ab_group_add                ~> linordered_ab_group_add
  1217     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  1218     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  1219     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  1220     ordered_field                       ~> linordered_field
  1221     ordered_field_no_lb                 ~> linordered_field_no_lb
  1222     ordered_field_no_ub                 ~> linordered_field_no_ub
  1223     ordered_field_dense_linear_order    ~> dense_linordered_field
  1224     ordered_idom                        ~> linordered_idom
  1225     ordered_ring                        ~> linordered_ring
  1226     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  1227     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  1228     ordered_ring_strict                 ~> linordered_ring_strict
  1229     ordered_semidom                     ~> linordered_semidom
  1230     ordered_semiring                    ~> linordered_semiring
  1231     ordered_semiring_1                  ~> linordered_semiring_1
  1232     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  1233     ordered_semiring_strict             ~> linordered_semiring_strict
  1234 
  1235   The following slightly odd type classes have been moved to a
  1236   separate theory Library/Lattice_Algebras:
  1237 
  1238     lordered_ab_group_add               ~> lattice_ab_group_add
  1239     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  1240     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  1241     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  1242     lordered_ring                       ~> lattice_ring
  1243 
  1244 INCOMPATIBILITY.
  1245 
  1246 * Refined field classes:
  1247   - classes division_ring_inverse_zero, field_inverse_zero,
  1248     linordered_field_inverse_zero include rule inverse 0 = 0 --
  1249     subsumes former division_by_zero class;
  1250   - numerous lemmas have been ported from field to division_ring.
  1251 INCOMPATIBILITY.
  1252 
  1253 * Refined algebra theorem collections:
  1254   - dropped theorem group group_simps, use algebra_simps instead;
  1255   - dropped theorem group ring_simps, use field_simps instead;
  1256   - proper theorem collection field_simps subsumes former theorem
  1257     groups field_eq_simps and field_simps;
  1258   - dropped lemma eq_minus_self_iff which is a duplicate for
  1259     equal_neg_zero.
  1260 INCOMPATIBILITY.
  1261 
  1262 * Theory Finite_Set and List: some lemmas have been generalized from
  1263 sets to lattices:
  1264 
  1265   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  1266   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  1267   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  1268   union_Union_fold_union        ~> sup_Sup_fold_sup
  1269   Inter_fold_inter              ~> Inf_fold_inf
  1270   Union_fold_union              ~> Sup_fold_sup
  1271   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  1272   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  1273   INTER_fold_inter              ~> INFI_fold_inf
  1274   UNION_fold_union              ~> SUPR_fold_sup
  1275 
  1276 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  1277 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  1278 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  1279 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  1280 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  1281 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  1282 
  1283 * Reorganized theory Multiset: swapped notation of pointwise and
  1284 multiset order:
  1285 
  1286   - pointwise ordering is instance of class order with standard syntax
  1287     <= and <;
  1288   - multiset ordering has syntax <=# and <#; partial order properties
  1289     are provided by means of interpretation with prefix
  1290     multiset_order;
  1291   - less duplication, less historical organization of sections,
  1292     conversion from associations lists to multisets, rudimentary code
  1293     generation;
  1294   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  1295     if needed.
  1296 
  1297 Renamed:
  1298 
  1299   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  1300   multi_count_ext  ~>  multiset_ext
  1301   diff_union_inverse2  ~>  diff_union_cancelR
  1302 
  1303 INCOMPATIBILITY.
  1304 
  1305 * Theory Permutation: replaced local "remove" by List.remove1.
  1306 
  1307 * Code generation: ML and OCaml code is decorated with signatures.
  1308 
  1309 * Theory List: added transpose.
  1310 
  1311 * Library/Nat_Bijection.thy is a collection of bijective functions
  1312 between nat and other types, which supersedes the older libraries
  1313 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  1314 
  1315   Constants:
  1316   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  1317   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  1318   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  1319   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  1320   Countable.pair_encode           ~> prod_encode
  1321   NatIso.prod2nat                 ~> prod_encode
  1322   NatIso.nat2prod                 ~> prod_decode
  1323   NatIso.sum2nat                  ~> sum_encode
  1324   NatIso.nat2sum                  ~> sum_decode
  1325   NatIso.list2nat                 ~> list_encode
  1326   NatIso.nat2list                 ~> list_decode
  1327   NatIso.set2nat                  ~> set_encode
  1328   NatIso.nat2set                  ~> set_decode
  1329 
  1330   Lemmas:
  1331   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  1332   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  1333   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  1334   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  1335   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  1336   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  1337   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  1338   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  1339   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  1340   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  1341   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  1342   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  1343   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  1344 
  1345 * Sledgehammer:
  1346   - Renamed ATP commands:
  1347     atp_info     ~> sledgehammer running_atps
  1348     atp_kill     ~> sledgehammer kill_atps
  1349     atp_messages ~> sledgehammer messages
  1350     atp_minimize ~> sledgehammer minimize
  1351     print_atps   ~> sledgehammer available_atps
  1352     INCOMPATIBILITY.
  1353   - Added user's manual ("isabelle doc sledgehammer").
  1354   - Added option syntax and "sledgehammer_params" to customize
  1355     Sledgehammer's behavior.  See the manual for details.
  1356   - Modified the Isar proof reconstruction code so that it produces
  1357     direct proofs rather than proofs by contradiction.  (This feature
  1358     is still experimental.)
  1359   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  1360     full-typed mode.
  1361   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  1362 
  1363 * Nitpick:
  1364   - Added and implemented "binary_ints" and "bits" options.
  1365   - Added "std" option and implemented support for nonstandard models.
  1366   - Added and implemented "finitize" option to improve the precision
  1367     of infinite datatypes based on a monotonicity analysis.
  1368   - Added support for quotient types.
  1369   - Added support for "specification" and "ax_specification"
  1370     constructs.
  1371   - Added support for local definitions (for "function" and
  1372     "termination" proofs).
  1373   - Added support for term postprocessors.
  1374   - Optimized "Multiset.multiset" and "FinFun.finfun".
  1375   - Improved efficiency of "destroy_constrs" optimization.
  1376   - Fixed soundness bugs related to "destroy_constrs" optimization and
  1377     record getters.
  1378   - Fixed soundness bug related to higher-order constructors.
  1379   - Fixed soundness bug when "full_descrs" is enabled.
  1380   - Improved precision of set constructs.
  1381   - Added "atoms" option.
  1382   - Added cache to speed up repeated Kodkod invocations on the same
  1383     problems.
  1384   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  1385     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  1386     "SAT4J_Light".  INCOMPATIBILITY.
  1387   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  1388     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  1389   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  1390 
  1391 * Method "induct" now takes instantiations of the form t, where t is not
  1392   a variable, as a shorthand for "x == t", where x is a fresh variable.
  1393   If this is not intended, t has to be enclosed in parentheses.
  1394   By default, the equalities generated by definitional instantiations
  1395   are pre-simplified, which may cause parameters of inductive cases
  1396   to disappear, or may even delete some of the inductive cases.
  1397   Use "induct (no_simp)" instead of "induct" to restore the old
  1398   behaviour. The (no_simp) option is also understood by the "cases"
  1399   and "nominal_induct" methods, which now perform pre-simplification, too.
  1400   INCOMPATIBILITY.
  1401 
  1402 
  1403 *** HOLCF ***
  1404 
  1405 * Variable names in lemmas generated by the domain package have
  1406 changed; the naming scheme is now consistent with the HOL datatype
  1407 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  1408 
  1409 * The domain package no longer defines the function "foo_copy" for
  1410 recursive domain "foo".  The reach lemma is now stated directly in
  1411 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  1412 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  1413 
  1414 * Most definedness lemmas generated by the domain package (previously
  1415 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  1416 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  1417 Proofs that used definedness lemmas as intro rules may break,
  1418 potential INCOMPATIBILITY.
  1419 
  1420 * Induction and casedist rules generated by the domain package now
  1421 declare proper case_names (one called "bottom", and one named for each
  1422 constructor).  INCOMPATIBILITY.
  1423 
  1424 * For mutually-recursive domains, separate "reach" and "take_lemma"
  1425 rules are generated for each domain, INCOMPATIBILITY.
  1426 
  1427   foo_bar.reach       ~> foo.reach  bar.reach
  1428   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  1429 
  1430 * Some lemmas generated by the domain package have been renamed for
  1431 consistency with the datatype package, INCOMPATIBILITY.
  1432 
  1433   foo.ind        ~> foo.induct
  1434   foo.finite_ind ~> foo.finite_induct
  1435   foo.coind      ~> foo.coinduct
  1436   foo.casedist   ~> foo.exhaust
  1437   foo.exhaust    ~> foo.nchotomy
  1438 
  1439 * For consistency with other definition packages, the fixrec package
  1440 now generates qualified theorem names, INCOMPATIBILITY.
  1441 
  1442   foo_simps  ~> foo.simps
  1443   foo_unfold ~> foo.unfold
  1444   foo_induct ~> foo.induct
  1445 
  1446 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  1447 method and internal fixrec proofs now use the default simpset instead.
  1448 INCOMPATIBILITY.
  1449 
  1450 * The "contlub" predicate has been removed.  Proof scripts should use
  1451 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  1452 
  1453 * The "admw" predicate has been removed, INCOMPATIBILITY.
  1454 
  1455 * The constants cpair, cfst, and csnd have been removed in favor of
  1456 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  1457 
  1458 
  1459 *** ML ***
  1460 
  1461 * Antiquotations for basic formal entities:
  1462 
  1463     @{class NAME}         -- type class
  1464     @{class_syntax NAME}  -- syntax representation of the above
  1465 
  1466     @{type_name NAME}     -- logical type
  1467     @{type_abbrev NAME}   -- type abbreviation
  1468     @{nonterminal NAME}   -- type of concrete syntactic category
  1469     @{type_syntax NAME}   -- syntax representation of any of the above
  1470 
  1471     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  1472     @{const_abbrev NAME}  -- abbreviated constant
  1473     @{const_syntax NAME}  -- syntax representation of any of the above
  1474 
  1475 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  1476 syntax constant (cf. 'syntax' command).
  1477 
  1478 * Antiquotation @{make_string} inlines a function to print arbitrary
  1479 values similar to the ML toplevel.  The result is compiler dependent
  1480 and may fall back on "?" in certain situations.
  1481 
  1482 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  1483 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  1484 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  1485 not work with the asynchronous Isar document model.
  1486 
  1487 * Configuration options now admit dynamic default values, depending on
  1488 the context or even global references.
  1489 
  1490 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  1491 uses an efficient external library if available (for Poly/ML).
  1492 
  1493 * Renamed some important ML structures, while keeping the old names
  1494 for some time as aliases within the structure Legacy:
  1495 
  1496   OuterKeyword  ~>  Keyword
  1497   OuterLex      ~>  Token
  1498   OuterParse    ~>  Parse
  1499   OuterSyntax   ~>  Outer_Syntax
  1500   PrintMode     ~>  Print_Mode
  1501   SpecParse     ~>  Parse_Spec
  1502   ThyInfo       ~>  Thy_Info
  1503   ThyLoad       ~>  Thy_Load
  1504   ThyOutput     ~>  Thy_Output
  1505   TypeInfer     ~>  Type_Infer
  1506 
  1507 Note that "open Legacy" simplifies porting of sources, but forgetting
  1508 to remove it again will complicate porting again in the future.
  1509 
  1510 * Most operations that refer to a global context are named
  1511 accordingly, e.g. Simplifier.global_context or
  1512 ProofContext.init_global.  There are some situations where a global
  1513 context actually works, but under normal circumstances one needs to
  1514 pass the proper local context through the code!
  1515 
  1516 * Discontinued old TheoryDataFun with its copy/init operation -- data
  1517 needs to be pure.  Functor Theory_Data_PP retains the traditional
  1518 Pretty.pp argument to merge, which is absent in the standard
  1519 Theory_Data version.
  1520 
  1521 * Sorts.certify_sort and derived "cert" operations for types and terms
  1522 no longer minimize sorts.  Thus certification at the boundary of the
  1523 inference kernel becomes invariant under addition of class relations,
  1524 which is an important monotonicity principle.  Sorts are now minimized
  1525 in the syntax layer only, at the boundary between the end-user and the
  1526 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  1527 explicitly in rare situations.
  1528 
  1529 * Renamed old-style Drule.standard to Drule.export_without_context, to
  1530 emphasize that this is in no way a standard operation.
  1531 INCOMPATIBILITY.
  1532 
  1533 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  1534 usual for resolution.  Rare INCOMPATIBILITY.
  1535 
  1536 * Renamed varify/unvarify operations to varify_global/unvarify_global
  1537 to emphasize that these only work in a global situation (which is
  1538 quite rare).
  1539 
  1540 * Curried take and drop in library.ML; negative length is interpreted
  1541 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  1542 
  1543 * Proof terms: type substitutions on proof constants now use canonical
  1544 order of type variables.  INCOMPATIBILITY for tools working with proof
  1545 terms.
  1546 
  1547 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  1548 may no longer carry premises.  User-level specifications are
  1549 transformed accordingly by Thm.add_axiom/add_def.
  1550 
  1551 
  1552 *** System ***
  1553 
  1554 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  1555 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  1556 proof terms are enabled unconditionally in the new HOL-Proofs image.
  1557 
  1558 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  1559 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  1560 respectively.
  1561 
  1562 * Old lib/scripts/polyml-platform is superseded by the
  1563 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  1564 variant, even on a 64 bit machine.  The following example setting
  1565 prefers 64 bit if available:
  1566 
  1567   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  1568 
  1569 * The preliminary Isabelle/jEdit application demonstrates the emerging
  1570 Isabelle/Scala layer for advanced prover interaction and integration.
  1571 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  1572 component.
  1573 
  1574 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  1575 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  1576 similar to the default assignment of the document preparation system
  1577 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  1578 provides some operations for direct access to the font without asking
  1579 the user for manual installation.
  1580 
  1581 
  1582 
  1583 New in Isabelle2009-1 (December 2009)
  1584 -------------------------------------
  1585 
  1586 *** General ***
  1587 
  1588 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  1589 one backslash should be used, even in ML sources.
  1590 
  1591 
  1592 *** Pure ***
  1593 
  1594 * Locale interpretation propagates mixins along the locale hierarchy.
  1595 The currently only available mixins are the equations used to map
  1596 local definitions to terms of the target domain of an interpretation.
  1597 
  1598 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  1599 loc" to print all interpretations of locale "loc" in the theory.
  1600 Interpretations in proofs are not shown.
  1601 
  1602 * Thoroughly revised locales tutorial.  New section on conditional
  1603 interpretation.
  1604 
  1605 * On instantiation of classes, remaining undefined class parameters
  1606 are formally declared.  INCOMPATIBILITY.
  1607 
  1608 
  1609 *** Document preparation ***
  1610 
  1611 * New generalized style concept for printing terms: @{foo (style) ...}
  1612 instead of @{foo_style style ...}  (old form is still retained for
  1613 backward compatibility).  Styles can be also applied for
  1614 antiquotations prop, term_type and typeof.
  1615 
  1616 
  1617 *** HOL ***
  1618 
  1619 * New proof method "smt" for a combination of first-order logic with
  1620 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  1621 fixed-size bitvectors; there is also basic support for higher-order
  1622 features (esp. lambda abstractions).  It is an incomplete decision
  1623 procedure based on external SMT solvers using the oracle mechanism;
  1624 for the SMT solver Z3, this method is proof-producing.  Certificates
  1625 are provided to avoid calling the external solvers solely for
  1626 re-checking proofs.  Due to a remote SMT service there is no need for
  1627 installing SMT solvers locally.  See src/HOL/SMT.
  1628 
  1629 * New commands to load and prove verification conditions generated by
  1630 the Boogie program verifier or derived systems (e.g. the Verifying C
  1631 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1632 
  1633 * New counterexample generator tool 'nitpick' based on the Kodkod
  1634 relational model finder.  See src/HOL/Tools/Nitpick and
  1635 src/HOL/Nitpick_Examples.
  1636 
  1637 * New commands 'code_pred' and 'values' to invoke the predicate
  1638 compiler and to enumerate values of inductive predicates.
  1639 
  1640 * A tabled implementation of the reflexive transitive closure.
  1641 
  1642 * New implementation of quickcheck uses generic code generator;
  1643 default generators are provided for all suitable HOL types, records
  1644 and datatypes.  Old quickcheck can be re-activated importing theory
  1645 Library/SML_Quickcheck.
  1646 
  1647 * New testing tool Mirabelle for automated proof tools.  Applies
  1648 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1649 every proof step in a theory.  To be used in batch mode via the
  1650 "mirabelle" utility.
  1651 
  1652 * New proof method "sos" (sum of squares) for nonlinear real
  1653 arithmetic (originally due to John Harison). It requires theory
  1654 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1655 works well in practice on quantifier-free real arithmetic with +, -,
  1656 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1657 inequalities between polynomials.  It makes use of external
  1658 semidefinite programming solvers.  Method "sos" generates a
  1659 certificate that can be pasted into the proof thus avoiding the need
  1660 to call an external tool every time the proof is checked.  See
  1661 src/HOL/Library/Sum_Of_Squares.
  1662 
  1663 * New method "linarith" invokes existing linear arithmetic decision
  1664 procedure only.
  1665 
  1666 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1667 
  1668 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1669 Causes full type information to be output to the ATPs.  This slows
  1670 ATPs down considerably but eliminates a source of unsound "proofs"
  1671 that fail later.
  1672 
  1673 * New method "metisFT": A version of metis that uses full type
  1674 information in order to avoid failures of proof reconstruction.
  1675 
  1676 * New evaluator "approximate" approximates an real valued term using
  1677 the same method as the approximation method.
  1678 
  1679 * Method "approximate" now supports arithmetic expressions as
  1680 boundaries of intervals and implements interval splitting and Taylor
  1681 series expansion.
  1682 
  1683 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1684 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1685 
  1686 * New theory SupInf of the supremum and infimum operators for sets of
  1687 reals.
  1688 
  1689 * New theory Probability, which contains a development of measure
  1690 theory, eventually leading to Lebesgue integration and probability.
  1691 
  1692 * Extended Multivariate Analysis to include derivation and Brouwer's
  1693 fixpoint theorem.
  1694 
  1695 * Reorganization of number theory, INCOMPATIBILITY:
  1696   - new number theory development for nat and int, in theories Divides
  1697     and GCD as well as in new session Number_Theory
  1698   - some constants and facts now suffixed with _nat and _int
  1699     accordingly
  1700   - former session NumberTheory now named Old_Number_Theory, including
  1701     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1702   - moved theory Pocklington from src/HOL/Library to
  1703     src/HOL/Old_Number_Theory
  1704 
  1705 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1706 lcm of finite and infinite sets. It is shown that they form a complete
  1707 lattice.
  1708 
  1709 * Class semiring_div requires superclass no_zero_divisors and proof of
  1710 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1711 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1712 generalized to class semiring_div, subsuming former theorems
  1713 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1714 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1715 INCOMPATIBILITY.
  1716 
  1717 * Refinements to lattice classes and sets:
  1718   - less default intro/elim rules in locale variant, more default
  1719     intro/elim rules in class variant: more uniformity
  1720   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1721     le_inf_iff
  1722   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1723     sup_aci)
  1724   - renamed ACI to inf_sup_aci
  1725   - new class "boolean_algebra"
  1726   - class "complete_lattice" moved to separate theory
  1727     "Complete_Lattice"; corresponding constants (and abbreviations)
  1728     renamed and with authentic syntax:
  1729     Set.Inf ~>    Complete_Lattice.Inf
  1730     Set.Sup ~>    Complete_Lattice.Sup
  1731     Set.INFI ~>   Complete_Lattice.INFI
  1732     Set.SUPR ~>   Complete_Lattice.SUPR
  1733     Set.Inter ~>  Complete_Lattice.Inter
  1734     Set.Union ~>  Complete_Lattice.Union
  1735     Set.INTER ~>  Complete_Lattice.INTER
  1736     Set.UNION ~>  Complete_Lattice.UNION
  1737   - authentic syntax for
  1738     Set.Pow
  1739     Set.image
  1740   - mere abbreviations:
  1741     Set.empty               (for bot)
  1742     Set.UNIV                (for top)
  1743     Set.inter               (for inf, formerly Set.Int)
  1744     Set.union               (for sup, formerly Set.Un)
  1745     Complete_Lattice.Inter  (for Inf)
  1746     Complete_Lattice.Union  (for Sup)
  1747     Complete_Lattice.INTER  (for INFI)
  1748     Complete_Lattice.UNION  (for SUPR)
  1749   - object-logic definitions as far as appropriate
  1750 
  1751 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1752 Un_subset_iff are explicitly deleted as default simp rules; then also
  1753 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1754 deleted to achieve the desired effect.
  1755 
  1756 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1757 rules by default any longer; the same applies to min_max.inf_absorb1
  1758 etc.  INCOMPATIBILITY.
  1759 
  1760 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1761 pred_set_conv by default.  INCOMPATIBILITY.
  1762 
  1763 * Power operations on relations and functions are now one dedicated
  1764 constant "compow" with infix syntax "^^".  Power operation on
  1765 multiplicative monoids retains syntax "^" and is now defined generic
  1766 in class power.  INCOMPATIBILITY.
  1767 
  1768 * Relation composition "R O S" now has a more standard argument order:
  1769 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1770 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1771 break, since the O_assoc rule was not rewritten like this.  Fix using
  1772 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1773 
  1774 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1775 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1776 INCOMPATIBILITY.
  1777 
  1778 * Most rules produced by inductive and datatype package have mandatory
  1779 prefixes.  INCOMPATIBILITY.
  1780 
  1781 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1782 the attribute of the same name.  Each of the theorems in the list
  1783 DERIV_intros assumes composition with an additional function and
  1784 matches a variable to the derivative, which has to be solved by the
  1785 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1786 of most elementary terms.  Former Maclauren.DERIV_tac and
  1787 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1788 INCOMPATIBILITY.
  1789 
  1790 * Code generator attributes follow the usual underscore convention:
  1791     code_unfold     replaces    code unfold
  1792     code_post       replaces    code post
  1793     etc.
  1794   INCOMPATIBILITY.
  1795 
  1796 * Renamed methods:
  1797     sizechange -> size_change
  1798     induct_scheme -> induction_schema
  1799   INCOMPATIBILITY.
  1800 
  1801 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1802 INCOMPATIBILITY, use "undefined" directly.
  1803 
  1804 * Renamed theorems:
  1805     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1806     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1807     Suc_plus1 -> Suc_eq_plus1
  1808     *anti_sym -> *antisym*
  1809     vector_less_eq_def -> vector_le_def
  1810   INCOMPATIBILITY.
  1811 
  1812 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1813 INCOMPATIBILITY.
  1814 
  1815 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1816 INCOMPATIBILITY.
  1817 
  1818 
  1819 *** HOLCF ***
  1820 
  1821 * Theory Representable defines a class "rep" of domains that are
  1822 representable (via an ep-pair) in the universal domain type "udom".
  1823 Instances are provided for all type constructors defined in HOLCF.
  1824 
  1825 * The 'new_domain' command is a purely definitional version of the
  1826 domain package, for representable domains.  Syntax is identical to the
  1827 old domain package.  The 'new_domain' package also supports indirect
  1828 recursion using previously-defined type constructors.  See
  1829 src/HOLCF/ex/New_Domain.thy for examples.
  1830 
  1831 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1832 on the left-hand side of an equation, and then performs
  1833 simplification.  Rewriting is done using rules declared with the
  1834 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1835 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1836 
  1837 * The pattern-match compiler in 'fixrec' can now handle constructors
  1838 with HOL function types.  Pattern-match combinators for the Pair
  1839 constructor are pre-configured.
  1840 
  1841 * The 'fixrec' package now produces better fixed-point induction rules
  1842 for mutually-recursive definitions:  Induction rules have conclusions
  1843 of the form "P foo bar" instead of "P <foo, bar>".
  1844 
  1845 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1846 been renamed to "below".  The name "below" now replaces "less" in many
  1847 theorem names.  (Legacy theorem names using "less" are still supported
  1848 as well.)
  1849 
  1850 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1851 patterns can be used to generate strictness rules, or to make
  1852 functions more strict (much like the bang-patterns supported by the
  1853 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1854 examples.
  1855 
  1856 
  1857 *** ML ***
  1858 
  1859 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1860 errors and run-time exceptions, including detailed source positions.
  1861 
  1862 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1863 identified entries, with some additional information such as source
  1864 position, logical grouping etc.
  1865 
  1866 * Theory and context data is now introduced by the simplified and
  1867 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1868 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1869 copy operation) is still available for some time.
  1870 
  1871 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1872 provides a high-level programming interface to synchronized state
  1873 variables with atomic update.  This works via pure function
  1874 application within a critical section -- its runtime should be as
  1875 short as possible; beware of deadlocks if critical code is nested,
  1876 either directly or indirectly via other synchronized variables!
  1877 
  1878 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1879 wraps raw ML references, explicitly indicating their non-thread-safe
  1880 behaviour.  The Isar toplevel keeps this structure open, to
  1881 accommodate Proof General as well as quick and dirty interactive
  1882 experiments with references.
  1883 
  1884 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1885 parallel tactical reasoning.
  1886 
  1887 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1888 are similar to SUBPROOF, but are slightly more flexible: only the
  1889 specified parts of the subgoal are imported into the context, and the
  1890 body tactic may introduce new subgoals and schematic variables.
  1891 
  1892 * Old tactical METAHYPS, which does not observe the proof context, has
  1893 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1894 or Subgoal.FOCUS etc.
  1895 
  1896 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  1897 functors have their own ML name space there is no point to mark them
  1898 separately.)  Minor INCOMPATIBILITY.
  1899 
  1900 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  1901 
  1902 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  1903 INCOMPATIBILITY.
  1904 
  1905 * Operations of structure Skip_Proof no longer require quick_and_dirty
  1906 mode, which avoids critical setmp.
  1907 
  1908 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  1909 combinators for "args".  INCOMPATIBILITY, need to use simplified
  1910 Attrib/Method.setup introduced in Isabelle2009.
  1911 
  1912 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  1913 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  1914 last resort.  INCOMPATIBILITY.
  1915 
  1916 * Display.pretty_thm now requires a proper context (cf. former
  1917 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  1918 or even Display.pretty_thm_without_context as last resort.
  1919 INCOMPATIBILITY.
  1920 
  1921 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  1922 Syntax.pretty_typ/term directly, preferably with proper context
  1923 instead of global theory.
  1924 
  1925 
  1926 *** System ***
  1927 
  1928 * Further fine tuning of parallel proof checking, scales up to 8 cores
  1929 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  1930 usedir option -q.
  1931 
  1932 * Support for additional "Isabelle components" via etc/components, see
  1933 also the system manual.
  1934 
  1935 * The isabelle makeall tool now operates on all components with
  1936 IsaMakefile, not just hardwired "logics".
  1937 
  1938 * Removed "compress" option from isabelle-process and isabelle usedir;
  1939 this is always enabled.
  1940 
  1941 * Discontinued support for Poly/ML 4.x versions.
  1942 
  1943 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  1944 on a given logic image.  This requires the lighttpd webserver and is
  1945 currently supported on Linux only.
  1946 
  1947 
  1948 
  1949 New in Isabelle2009 (April 2009)
  1950 --------------------------------
  1951 
  1952 *** General ***
  1953 
  1954 * Simplified main Isabelle executables, with less surprises on
  1955 case-insensitive file-systems (such as Mac OS).
  1956 
  1957   - The main Isabelle tool wrapper is now called "isabelle" instead of
  1958     "isatool."
  1959 
  1960   - The former "isabelle" alias for "isabelle-process" has been
  1961     removed (should rarely occur to regular users).
  1962 
  1963   - The former "isabelle-interface" and its alias "Isabelle" have been
  1964     removed (interfaces are now regular Isabelle tools).
  1965 
  1966 Within scripts and make files, the Isabelle environment variables
  1967 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  1968 respectively.  (The latter are still available as legacy feature.)
  1969 
  1970 The old isabelle-interface wrapper could react in confusing ways if
  1971 the interface was uninstalled or changed otherwise.  Individual
  1972 interface tool configuration is now more explicit, see also the
  1973 Isabelle system manual.  In particular, Proof General is now available
  1974 via "isabelle emacs".
  1975 
  1976 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  1977 purge installed copies of Isabelle executables and re-run "isabelle
  1978 install -p ...", or use symlinks.
  1979 
  1980 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  1981 old ~/isabelle, which was slightly non-standard and apt to cause
  1982 surprises on case-insensitive file-systems (such as Mac OS).
  1983 
  1984 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  1985 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  1986 care is required when using older releases of Isabelle.  Note that
  1987 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  1988 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  1989 
  1990 * Proofs of fully specified statements are run in parallel on
  1991 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  1992 a regular 4-core machine, if the initial heap space is made reasonably
  1993 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  1994 
  1995 * The main reference manuals ("isar-ref", "implementation", and
  1996 "system") have been updated and extended.  Formally checked references
  1997 as hyperlinks are now available uniformly.
  1998 
  1999 
  2000 *** Pure ***
  2001 
  2002 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  2003 respects.  The most important changes are listed below.  See the
  2004 Tutorial on Locales ("locales" manual) for details.
  2005 
  2006 - In locale expressions, instantiation replaces renaming.  Parameters
  2007 must be declared in a for clause.  To aid compatibility with previous
  2008 parameter inheritance, in locale declarations, parameters that are not
  2009 'touched' (instantiation position "_" or omitted) are implicitly added
  2010 with their syntax at the beginning of the for clause.
  2011 
  2012 - Syntax from abbreviations and definitions in locales is available in
  2013 locale expressions and context elements.  The latter is particularly
  2014 useful in locale declarations.
  2015 
  2016 - More flexible mechanisms to qualify names generated by locale
  2017 expressions.  Qualifiers (prefixes) may be specified in locale
  2018 expressions, and can be marked as mandatory (syntax: "name!:") or
  2019 optional (syntax "name?:").  The default depends for plain "name:"
  2020 depends on the situation where a locale expression is used: in
  2021 commands 'locale' and 'sublocale' prefixes are optional, in
  2022 'interpretation' and 'interpret' prefixes are mandatory.  The old
  2023 implicit qualifiers derived from the parameter names of a locale are
  2024 no longer generated.
  2025 
  2026 - Command "sublocale l < e" replaces "interpretation l < e".  The
  2027 instantiation clause in "interpretation" and "interpret" (square
  2028 brackets) is no longer available.  Use locale expressions.
  2029 
  2030 - When converting proof scripts, mandatory qualifiers in
  2031 'interpretation' and 'interpret' should be retained by default, even
  2032 if this is an INCOMPATIBILITY compared to former behavior.  In the
  2033 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  2034 in locale expressions range over a single locale instance only.
  2035 
  2036 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  2037 In existing theorem specifications replace the includes element by the
  2038 respective context elements of the included locale, omitting those
  2039 that are already present in the theorem specification.  Multiple
  2040 assume elements of a locale should be replaced by a single one
  2041 involving the locale predicate.  In the proof body, declarations (most
  2042 notably theorems) may be regained by interpreting the respective
  2043 locales in the proof context as required (command "interpret").
  2044 
  2045 If using "includes" in replacement of a target solely because the
  2046 parameter types in the theorem are not as general as in the target,
  2047 consider declaring a new locale with additional type constraints on
  2048 the parameters (context element "constrains").
  2049 
  2050 - Discontinued "locale (open)".  INCOMPATIBILITY.
  2051 
  2052 - Locale interpretation commands no longer attempt to simplify goal.
  2053 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  2054 methods intro_locales and unfold_locales to clarify.
  2055 
  2056 - Locale interpretation commands no longer accept interpretation
  2057 attributes.  INCOMPATIBILITY.
  2058 
  2059 * Class declaration: so-called "base sort" must not be given in import
  2060 list any longer, but is inferred from the specification.  Particularly
  2061 in HOL, write
  2062 
  2063     class foo = ...
  2064 
  2065 instead of
  2066 
  2067     class foo = type + ...
  2068 
  2069 * Class target: global versions of theorems stemming do not carry a
  2070 parameter prefix any longer.  INCOMPATIBILITY.
  2071 
  2072 * Class 'instance' command no longer accepts attached definitions.
  2073 INCOMPATIBILITY, use proper 'instantiation' target instead.
  2074 
  2075 * Recovered hiding of consts, which was accidentally broken in
  2076 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  2077 makes c inaccessible; consider using ``hide (open) const c'' instead.
  2078 
  2079 * Slightly more coherent Pure syntax, with updated documentation in
  2080 isar-ref manual.  Removed locales meta_term_syntax and
  2081 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  2082 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  2083 directly in regular applications.
  2084 
  2085 * There is a new syntactic category "float_const" for signed decimal
  2086 fractions (e.g. 123.45 or -123.45).
  2087 
  2088 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  2089 interface with 'setup' command instead.
  2090 
  2091 * Command 'local_setup' is similar to 'setup', but operates on a local
  2092 theory context.
  2093 
  2094 * The 'axiomatization' command now only works within a global theory
  2095 context.  INCOMPATIBILITY.
  2096 
  2097 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  2098 hypotheses.  Sorts required in the course of reasoning need to be
  2099 covered by the constraints in the initial statement, completed by the
  2100 type instance information of the background theory.  Non-trivial sort
  2101 hypotheses, which rarely occur in practice, may be specified via
  2102 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  2103 
  2104   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  2105 
  2106 The result contains an implicit sort hypotheses as before --
  2107 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  2108 normalization.
  2109 
  2110 * Generalized Isar history, with support for linear undo, direct state
  2111 addressing etc.
  2112 
  2113 * Changed defaults for unify configuration options:
  2114 
  2115   unify_trace_bound = 50 (formerly 25)
  2116   unify_search_bound = 60 (formerly 30)
  2117 
  2118 * Different bookkeeping for code equations (INCOMPATIBILITY):
  2119 
  2120   a) On theory merge, the last set of code equations for a particular
  2121      constant is taken (in accordance with the policy applied by other
  2122      parts of the code generator framework).
  2123 
  2124   b) Code equations stemming from explicit declarations (e.g. code
  2125      attribute) gain priority over default code equations stemming
  2126      from definition, primrec, fun etc.
  2127 
  2128 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  2129 
  2130 * Unified theorem tables for both code generators.  Thus [code
  2131 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  2132 
  2133 * Command 'find_consts' searches for constants based on type and name
  2134 patterns, e.g.
  2135 
  2136     find_consts "_ => bool"
  2137 
  2138 By default, matching is against subtypes, but it may be restricted to
  2139 the whole type.  Searching by name is possible.  Multiple queries are
  2140 conjunctive and queries may be negated by prefixing them with a
  2141 hyphen:
  2142 
  2143     find_consts strict: "_ => bool" name: "Int" -"int => int"
  2144 
  2145 * New 'find_theorems' criterion "solves" matches theorems that
  2146 directly solve the current goal (modulo higher-order unification).
  2147 
  2148 * Auto solve feature for main theorem statements: whenever a new goal
  2149 is stated, "find_theorems solves" is called; any theorems that could
  2150 solve the lemma directly are listed as part of the goal state.
  2151 Cf. associated options in Proof General Isabelle settings menu,
  2152 enabled by default, with reasonable timeout for pathological cases of
  2153 higher-order unification.
  2154 
  2155 
  2156 *** Document preparation ***
  2157 
  2158 * Antiquotation @{lemma} now imitates a regular terminal proof,
  2159 demanding keyword 'by' and supporting the full method expression
  2160 syntax just like the Isar command 'by'.
  2161 
  2162 
  2163 *** HOL ***
  2164 
  2165 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  2166 points Main and Complex_Main remain as before.
  2167 
  2168 * Logic image HOL-Plain provides a minimal HOL with the most important
  2169 tools available (inductive, datatype, primrec, ...).  This facilitates
  2170 experimentation and tool development.  Note that user applications
  2171 (and library theories) should never refer to anything below theory
  2172 Main, as before.
  2173 
  2174 * Logic image HOL-Main stops at theory Main, and thus facilitates
  2175 experimentation due to shorter build times.
  2176 
  2177 * Logic image HOL-NSA contains theories of nonstandard analysis which
  2178 were previously part of former HOL-Complex.  Entry point Hyperreal
  2179 remains valid, but theories formerly using Complex_Main should now use
  2180 new entry point Hypercomplex.
  2181 
  2182 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  2183 Posix processes.  Avoids potentially expensive forking of the ML
  2184 process.  New thread-based implementation also works on non-Unix
  2185 platforms (Cygwin).  Provers are no longer hardwired, but defined
  2186 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  2187 commands are covered in the isar-ref manual.
  2188 
  2189 * Wrapper scripts for remote SystemOnTPTP service allows to use
  2190 sledgehammer without local ATP installation (Vampire etc.). Other
  2191 provers may be included via suitable ML wrappers, see also
  2192 src/HOL/ATP_Linkup.thy.
  2193 
  2194 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  2195 menu.
  2196 
  2197 * The metis method no longer fails because the theorem is too trivial
  2198 (contains the empty clause).
  2199 
  2200 * The metis method now fails in the usual manner, rather than raising
  2201 an exception, if it determines that it cannot prove the theorem.
  2202 
  2203 * Method "coherent" implements a prover for coherent logic (see also
  2204 src/Tools/coherent.ML).
  2205 
  2206 * Constants "undefined" and "default" replace "arbitrary".  Usually
  2207 "undefined" is the right choice to replace "arbitrary", though
  2208 logically there is no difference.  INCOMPATIBILITY.
  2209 
  2210 * Command "value" now integrates different evaluation mechanisms.  The
  2211 result of the first successful evaluation mechanism is printed.  In
  2212 square brackets a particular named evaluation mechanisms may be
  2213 specified (currently, [SML], [code] or [nbe]).  See further
  2214 src/HOL/ex/Eval_Examples.thy.
  2215 
  2216 * Normalization by evaluation now allows non-leftlinear equations.
  2217 Declare with attribute [code nbe].
  2218 
  2219 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  2220 as the structured Isar versions "cases" and "induct", cf. the
  2221 corresponding "cases" and "induct" attributes.  Mutual induction rules
  2222 are now presented as a list of individual projections
  2223 (e.g. foo_bar.inducts for types foo and bar); the old format with
  2224 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  2225 rare situations a different rule is selected --- notably nested tuple
  2226 elimination instead of former prod.exhaust: use explicit (case_tac t
  2227 rule: prod.exhaust) here.
  2228 
  2229 * Attributes "cases", "induct", "coinduct" support "del" option.
  2230 
  2231 * Removed fact "case_split_thm", which duplicates "case_split".
  2232 
  2233 * The option datatype has been moved to a new theory Option.  Renamed
  2234 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  2235 
  2236 * New predicate "strict_mono" classifies strict functions on partial
  2237 orders.  With strict functions on linear orders, reasoning about
  2238 (in)equalities is facilitated by theorems "strict_mono_eq",
  2239 "strict_mono_less_eq" and "strict_mono_less".
  2240 
  2241 * Some set operations are now proper qualified constants with
  2242 authentic syntax.  INCOMPATIBILITY:
  2243 
  2244     op Int ~>   Set.Int
  2245     op Un ~>    Set.Un
  2246     INTER ~>    Set.INTER
  2247     UNION ~>    Set.UNION
  2248     Inter ~>    Set.Inter
  2249     Union ~>    Set.Union
  2250     {} ~>       Set.empty
  2251     UNIV ~>     Set.UNIV
  2252 
  2253 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  2254 theory Set.
  2255 
  2256 * Auxiliary class "itself" has disappeared -- classes without any
  2257 parameter are treated as expected by the 'class' command.
  2258 
  2259 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  2260 
  2261 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  2262 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  2263 
  2264 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  2265 method "approximation".  It proves formulas on real values by using
  2266 interval arithmetic.  In the formulas are also the transcendental
  2267 functions sin, cos, tan, atan, ln, exp and the constant pi are
  2268 allowed. For examples see
  2269 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  2270 
  2271 * Theory "Reflection" now resides in HOL/Library.
  2272 
  2273 * Entry point to Word library now simply named "Word".
  2274 INCOMPATIBILITY.
  2275 
  2276 * Made source layout more coherent with logical distribution
  2277 structure:
  2278 
  2279     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  2280     src/HOL/Library/Code_Message.thy ~> src/HOL/
  2281     src/HOL/Library/GCD.thy ~> src/HOL/
  2282     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  2283     src/HOL/Library/Parity.thy ~> src/HOL/
  2284     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  2285     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  2286     src/HOL/Real/Lubs.thy ~> src/HOL/
  2287     src/HOL/Real/PReal.thy ~> src/HOL/
  2288     src/HOL/Real/Rational.thy ~> src/HOL/
  2289     src/HOL/Real/RComplete.thy ~> src/HOL/
  2290     src/HOL/Real/RealDef.thy ~> src/HOL/
  2291     src/HOL/Real/RealPow.thy ~> src/HOL/
  2292     src/HOL/Real/Real.thy ~> src/HOL/
  2293     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  2294     src/HOL/Complex/Complex.thy ~> src/HOL/
  2295     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  2296     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  2297     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  2298     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  2299     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  2300     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  2301     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  2302     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  2303     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  2304     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  2305     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  2306     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  2307     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  2308     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  2309     src/HOL/Real/Float ~> src/HOL/Library/
  2310     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  2311     src/HOL/Real/RealVector.thy ~> src/HOL/
  2312 
  2313     src/HOL/arith_data.ML ~> src/HOL/Tools
  2314     src/HOL/hologic.ML ~> src/HOL/Tools
  2315     src/HOL/simpdata.ML ~> src/HOL/Tools
  2316     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  2317     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  2318     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  2319     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  2320     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  2321     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  2322     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  2323 
  2324     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  2325     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  2326     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  2327     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  2328     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  2329     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  2330 
  2331 * If methods "eval" and "evaluation" encounter a structured proof
  2332 state with !!/==>, only the conclusion is evaluated to True (if
  2333 possible), avoiding strange error messages.
  2334 
  2335 * Method "sizechange" automates termination proofs using (a
  2336 modification of) the size-change principle.  Requires SAT solver.  See
  2337 src/HOL/ex/Termination.thy for examples.
  2338 
  2339 * Simplifier: simproc for let expressions now unfolds if bound
  2340 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  2341 
  2342 * Method "arith": Linear arithmetic now ignores all inequalities when
  2343 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  2344 
  2345 * New attribute "arith" for facts that should always be used
  2346 automatically by arithmetic. It is intended to be used locally in
  2347 proofs, e.g.
  2348 
  2349   assumes [arith]: "x > 0"
  2350 
  2351 Global usage is discouraged because of possible performance impact.
  2352 
  2353 * New classes "top" and "bot" with corresponding operations "top" and
  2354 "bot" in theory Orderings; instantiation of class "complete_lattice"
  2355 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  2356 
  2357 * Changed definition lemma "less_fun_def" in order to provide an
  2358 instance for preorders on functions; use lemma "less_le" instead.
  2359 INCOMPATIBILITY.
  2360 
  2361 * Theory Orderings: class "wellorder" moved here, with explicit
  2362 induction rule "less_induct" as assumption.  For instantiation of
  2363 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  2364 INCOMPATIBILITY.
  2365 
  2366 * Theory Orderings: added class "preorder" as superclass of "order".
  2367 INCOMPATIBILITY: Instantiation proofs for order, linorder
  2368 etc. slightly changed.  Some theorems named order_class.* now named
  2369 preorder_class.*.
  2370 
  2371 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  2372 "diag" to "Id_on".
  2373 
  2374 * Theory Finite_Set: added a new fold combinator of type
  2375 
  2376   ('a => 'b => 'b) => 'b => 'a set => 'b
  2377 
  2378 Occasionally this is more convenient than the old fold combinator
  2379 which is now defined in terms of the new one and renamed to
  2380 fold_image.
  2381 
  2382 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  2383 and "ring_simps" have been replaced by "algebra_simps" (which can be
  2384 extended with further lemmas!).  At the moment both still exist but
  2385 the former will disappear at some point.
  2386 
  2387 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  2388 class recpower.  Type-specific simp rules for various recpower types
  2389 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  2390 
  2391 rat_power_0    -> power_0
  2392 rat_power_Suc  -> power_Suc
  2393 realpow_0      -> power_0
  2394 realpow_Suc    -> power_Suc
  2395 complexpow_0   -> power_0
  2396 complexpow_Suc -> power_Suc
  2397 power_poly_0   -> power_0
  2398 power_poly_Suc -> power_Suc
  2399 
  2400 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  2401 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  2402 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  2403 of lemmas from Divides has been generalized from nat to class
  2404 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  2405 renames resulting from duplicate elimination:
  2406 
  2407     dvd_def_mod ~>          dvd_eq_mod_eq_0
  2408     zero_dvd_iff ~>         dvd_0_left_iff
  2409     dvd_0 ~>                dvd_0_right
  2410     DIVISION_BY_ZERO_DIV ~> div_by_0
  2411     DIVISION_BY_ZERO_MOD ~> mod_by_0
  2412     mult_div ~>             div_mult_self2_is_id
  2413     mult_mod ~>             mod_mult_self2_is_0
  2414 
  2415 * Theory IntDiv: removed many lemmas that are instances of class-based
  2416 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  2417 rename old lemmas as follows:
  2418 
  2419 dvd_diff               -> nat_dvd_diff
  2420 dvd_zminus_iff         -> dvd_minus_iff
  2421 mod_add1_eq            -> mod_add_eq
  2422 mod_mult1_eq           -> mod_mult_right_eq
  2423 mod_mult1_eq'          -> mod_mult_left_eq
  2424 mod_mult_distrib_mod   -> mod_mult_eq
  2425 nat_mod_add_left_eq    -> mod_add_left_eq
  2426 nat_mod_add_right_eq   -> mod_add_right_eq
  2427 nat_mod_div_trivial    -> mod_div_trivial
  2428 nat_mod_mod_trivial    -> mod_mod_trivial
  2429 zdiv_zadd_self1        -> div_add_self1
  2430 zdiv_zadd_self2        -> div_add_self2
  2431 zdiv_zmult_self1       -> div_mult_self2_is_id
  2432 zdiv_zmult_self2       -> div_mult_self1_is_id
  2433 zdvd_triv_left         -> dvd_triv_left
  2434 zdvd_triv_right        -> dvd_triv_right
  2435 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  2436 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  2437 zmod_zadd_left_eq      -> mod_add_left_eq
  2438 zmod_zadd_right_eq     -> mod_add_right_eq
  2439 zmod_zadd_self1        -> mod_add_self1
  2440 zmod_zadd_self2        -> mod_add_self2
  2441 zmod_zadd1_eq          -> mod_add_eq
  2442 zmod_zdiff1_eq         -> mod_diff_eq
  2443 zmod_zdvd_zmod         -> mod_mod_cancel
  2444 zmod_zmod_cancel       -> mod_mod_cancel
  2445 zmod_zmult_self1       -> mod_mult_self2_is_0
  2446 zmod_zmult_self2       -> mod_mult_self1_is_0
  2447 zmod_1                 -> mod_by_1
  2448 zdiv_1                 -> div_by_1
  2449 zdvd_abs1              -> abs_dvd_iff
  2450 zdvd_abs2              -> dvd_abs_iff
  2451 zdvd_refl              -> dvd_refl
  2452 zdvd_trans             -> dvd_trans
  2453 zdvd_zadd              -> dvd_add
  2454 zdvd_zdiff             -> dvd_diff
  2455 zdvd_zminus_iff        -> dvd_minus_iff
  2456 zdvd_zminus2_iff       -> minus_dvd_iff
  2457 zdvd_zmultD            -> dvd_mult_right
  2458 zdvd_zmultD2           -> dvd_mult_left
  2459 zdvd_zmult_mono        -> mult_dvd_mono
  2460 zdvd_0_right           -> dvd_0_right
  2461 zdvd_0_left            -> dvd_0_left_iff
  2462 zdvd_1_left            -> one_dvd
  2463 zminus_dvd_iff         -> minus_dvd_iff
  2464 
  2465 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  2466 
  2467 * The real numbers offer decimal input syntax: 12.34 is translated
  2468 into 1234/10^2. This translation is not reversed upon output.
  2469 
  2470 * Theory Library/Polynomial defines an abstract type 'a poly of
  2471 univariate polynomials with coefficients of type 'a.  In addition to
  2472 the standard ring operations, it also supports div and mod.  Code
  2473 generation is also supported, using list-style constructors.
  2474 
  2475 * Theory Library/Inner_Product defines a class of real_inner for real
  2476 inner product spaces, with an overloaded operation inner :: 'a => 'a
  2477 => real.  Class real_inner is a subclass of real_normed_vector from
  2478 theory RealVector.
  2479 
  2480 * Theory Library/Product_Vector provides instances for the product
  2481 type 'a * 'b of several classes from RealVector and Inner_Product.
  2482 Definitions of addition, subtraction, scalar multiplication, norms,
  2483 and inner products are included.
  2484 
  2485 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  2486 addition to the field operations, numerals and case syntax are also
  2487 supported.
  2488 
  2489 * Theory Library/Diagonalize provides constructive version of Cantor's
  2490 first diagonalization argument.
  2491 
  2492 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  2493 zlcm (for int); carried together from various gcd/lcm developements in
  2494 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  2495 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  2496 may recover tupled syntax as follows:
  2497 
  2498     hide (open) const gcd
  2499     abbreviation gcd where
  2500       "gcd == (%(a, b). GCD.gcd a b)"
  2501     notation (output)
  2502       GCD.gcd ("gcd '(_, _')")
  2503 
  2504 The same works for lcm, zgcd, zlcm.
  2505 
  2506 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  2507 instantiations for algebraic structures.  Removed some duplicate
  2508 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  2509 
  2510 * ML antiquotation @{code} takes a constant as argument and generates
  2511 corresponding code in background and inserts name of the corresponding
  2512 resulting ML value/function/datatype constructor binding in place.
  2513 All occurrences of @{code} with a single ML block are generated
  2514 simultaneously.  Provides a generic and safe interface for
  2515 instrumentalizing code generation.  See
  2516 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  2517 In future you ought to refrain from ad-hoc compiling generated SML
  2518 code on the ML toplevel.  Note that (for technical reasons) @{code}
  2519 cannot refer to constants for which user-defined serializations are
  2520 set.  Refer to the corresponding ML counterpart directly in that
  2521 cases.
  2522 
  2523 * Command 'rep_datatype': instead of theorem names the command now
  2524 takes a list of terms denoting the constructors of the type to be
  2525 represented as datatype.  The characteristic theorems have to be
  2526 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  2527 have disappeared in favour of existing ones:
  2528 
  2529     unit_induct                 ~> unit.induct
  2530     prod_induct                 ~> prod.induct
  2531     sum_induct                  ~> sum.induct
  2532     Suc_Suc_eq                  ~> nat.inject
  2533     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  2534 
  2535 
  2536 *** HOL-Algebra ***
  2537 
  2538 * New locales for orders and lattices where the equivalence relation
  2539 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  2540 locales use a record structure with field eq for the equivalence.
  2541 
  2542 * New theory of factorial domains.
  2543 
  2544 * Units_l_inv and Units_r_inv are now simp rules by default.
  2545 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  2546 and/or r_inv will now also require deletion of these lemmas.
  2547 
  2548 * Renamed the following theorems, INCOMPATIBILITY:
  2549 
  2550 UpperD ~> Upper_memD
  2551 LowerD ~> Lower_memD
  2552 least_carrier ~> least_closed
  2553 greatest_carrier ~> greatest_closed
  2554 greatest_Lower_above ~> greatest_Lower_below
  2555 one_zero ~> carrier_one_zero
  2556 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  2557 
  2558 
  2559 *** HOL-Nominal ***
  2560 
  2561 * Nominal datatypes can now contain type-variables.
  2562 
  2563 * Commands 'nominal_inductive' and 'equivariance' work with local
  2564 theory targets.
  2565 
  2566 * Nominal primrec can now works with local theory targets and its
  2567 specification syntax now conforms to the general format as seen in
  2568 'inductive' etc.
  2569 
  2570 * Method "perm_simp" honours the standard simplifier attributes
  2571 (no_asm), (no_asm_use) etc.
  2572 
  2573 * The new predicate #* is defined like freshness, except that on the
  2574 left hand side can be a set or list of atoms.
  2575 
  2576 * Experimental command 'nominal_inductive2' derives strong induction
  2577 principles for inductive definitions.  In contrast to
  2578 'nominal_inductive', which can only deal with a fixed number of
  2579 binders, it can deal with arbitrary expressions standing for sets of
  2580 atoms to be avoided.  The only inductive definition we have at the
  2581 moment that needs this generalisation is the typing rule for Lets in
  2582 the algorithm W:
  2583 
  2584  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  2585  -----------------------------------------------------------------
  2586          Gamma |- Let x be t1 in t2 : T2
  2587 
  2588 In this rule one wants to avoid all the binders that are introduced by
  2589 "close Gamma T1".  We are looking for other examples where this
  2590 feature might be useful.  Please let us know.
  2591 
  2592 
  2593 *** HOLCF ***
  2594 
  2595 * Reimplemented the simplification procedure for proving continuity
  2596 subgoals.  The new simproc is extensible; users can declare additional
  2597 continuity introduction rules with the attribute [cont2cont].
  2598 
  2599 * The continuity simproc now uses a different introduction rule for
  2600 solving continuity subgoals on terms with lambda abstractions.  In
  2601 some rare cases the new simproc may fail to solve subgoals that the
  2602 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  2603 Potential INCOMPATIBILITY.
  2604 
  2605 * Command 'fixrec': specification syntax now conforms to the general
  2606 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  2607 examples.  INCOMPATIBILITY.
  2608 
  2609 
  2610 *** ZF ***
  2611 
  2612 * Proof of Zorn's Lemma for partial orders.
  2613 
  2614 
  2615 *** ML ***
  2616 
  2617 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  2618 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  2619 depends on multithreading, so timouts will not work before Poly/ML
  2620 5.2.1!
  2621 
  2622 * High-level support for concurrent ML programming, see
  2623 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  2624 particularly convenient to organize independent functional
  2625 computations.  The concept of "synchronized variables" provides a
  2626 higher-order interface for components with shared state, avoiding the
  2627 delicate details of mutexes and condition variables.  (Requires
  2628 Poly/ML 5.2.1 or later.)
  2629 
  2630 * ML bindings produced via Isar commands are stored within the Isar
  2631 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2632 become thread-safe and work with undo as expected (concerning
  2633 top-level bindings, not side-effects on global references).
  2634 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2635 compiler at runtime; really global bindings need to be given outside a
  2636 theory.  (Requires Poly/ML 5.2 or later.)
  2637 
  2638 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2639 context.  Top-level ML bindings are stored within the proof context in
  2640 a purely sequential fashion, disregarding the nested proof structure.
  2641 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2642 proof.  (Requires Poly/ML 5.2 or later.)
  2643 
  2644 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2645 and Method.setup, as well as Isar commands 'attribute_setup' and
  2646 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2647 existing code accordingly, or use plain 'setup' together with old
  2648 Method.add_method.
  2649 
  2650 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2651 to 'a -> thm, while results are always tagged with an authentic oracle
  2652 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2653 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2654 accordingly.  Note that extra performance may be gained by producing
  2655 the cterm carefully, avoiding slow Thm.cterm_of.
  2656 
  2657 * Simplified interface for defining document antiquotations via
  2658 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2659 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2660 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2661 examples.
  2662 
  2663 * More systematic treatment of long names, abstract name bindings, and
  2664 name space operations.  Basic operations on qualified names have been
  2665 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2666 Long_Name.append.  Old type bstring has been mostly replaced by
  2667 abstract type binding (see structure Binding), which supports precise
  2668 qualification by packages and local theory targets, as well as proper
  2669 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2670 bstring values into Binding.name, or better pass through abstract
  2671 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2672 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2673 
  2674 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2675 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2676 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2677 
  2678 * Disposed old type and term read functions (Sign.read_def_typ,
  2679 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2680 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2681 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2682 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2683 resort for legacy applications.
  2684 
  2685 * Disposed old declarations, tactics, tactic combinators that refer to
  2686 the simpset or claset of an implicit theory (such as Addsimps,
  2687 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2688 embedded ML text, or local_simpset_of with a proper context passed as
  2689 explicit runtime argument.
  2690 
  2691 * Rules and tactics that read instantiations (read_instantiate,
  2692 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2693 context, which is required for parsing and type-checking.  Moreover,
  2694 the variables are specified as plain indexnames, not string encodings
  2695 thereof.  INCOMPATIBILITY.
  2696 
  2697 * Generic Toplevel.add_hook interface allows to analyze the result of
  2698 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2699 for theorem dependency output of transactions resulting in a new
  2700 theory state.
  2701 
  2702 * ML antiquotations: block-structured compilation context indicated by
  2703 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2704 
  2705   @{binding name}                         - basic name binding
  2706   @{let ?pat = term}                      - term abbreviation (HO matching)
  2707   @{note name = fact}                     - fact abbreviation
  2708   @{thm fact}                             - singleton fact (with attributes)
  2709   @{thms fact}                            - general fact (with attributes)
  2710   @{lemma prop by method}                 - singleton goal
  2711   @{lemma prop by meth1 meth2}            - singleton goal
  2712   @{lemma prop1 ... propN by method}      - general goal
  2713   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2714   @{lemma (open) ...}                     - open derivation
  2715 
  2716 
  2717 *** System ***
  2718 
  2719 * The Isabelle "emacs" tool provides a specific interface to invoke
  2720 Proof General / Emacs, with more explicit failure if that is not
  2721 installed (the old isabelle-interface script silently falls back on
  2722 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2723 installation location of the Proof General distribution.
  2724 
  2725 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2726 the Isabelle process into a JVM/Scala application.  See
  2727 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2728 process wrapper has been discontinued.)
  2729 
  2730 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2731 
  2732 * Various status messages (with exact source position information) are
  2733 emitted, if proper markup print mode is enabled.  This allows
  2734 user-interface components to provide detailed feedback on internal
  2735 prover operations.
  2736 
  2737 
  2738 
  2739 New in Isabelle2008 (June 2008)
  2740 -------------------------------
  2741 
  2742 *** General ***
  2743 
  2744 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2745 and updated, with formally checked references as hyperlinks.
  2746 
  2747 * Theory loader: use_thy (and similar operations) no longer set the
  2748 implicit ML context, which was occasionally hard to predict and in
  2749 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2750 provides a proper context already.
  2751 
  2752 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2753 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2754 'use' within a theory file will do the job.
  2755 
  2756 * Name space merge now observes canonical order, i.e. the second space
  2757 is inserted into the first one, while existing entries in the first
  2758 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2759 swap theory imports.
  2760 
  2761 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2762 INCOMPATIBILITY in identifier syntax etc.
  2763 
  2764 * Outer syntax: string tokens no longer admit escaped white space,
  2765 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2766 white space without escapes.
  2767 
  2768 * Outer syntax: string tokens may contain arbitrary character codes
  2769 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2770 "foo_bar".
  2771 
  2772 
  2773 *** Pure ***
  2774 
  2775 * Context-dependent token translations.  Default setup reverts locally
  2776 fixed variables, and adds hilite markup for undeclared frees.
  2777 
  2778 * Unused theorems can be found using the new command 'unused_thms'.
  2779 There are three ways of invoking it:
  2780 
  2781 (1) unused_thms
  2782      Only finds unused theorems in the current theory.
  2783 
  2784 (2) unused_thms thy_1 ... thy_n -
  2785      Finds unused theorems in the current theory and all of its ancestors,
  2786      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2787 
  2788 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2789      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2790      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2791      their ancestors.
  2792 
  2793 In order to increase the readability of the list produced by
  2794 unused_thms, theorems that have been created by a particular instance
  2795 of a theory command such as 'inductive' or 'function' are considered
  2796 to belong to the same "group", meaning that if at least one theorem in
  2797 this group is used, the other theorems in the same group are no longer
  2798 reported as unused.  Moreover, if all theorems in the group are
  2799 unused, only one theorem in the group is displayed.
  2800 
  2801 Note that proof objects have to be switched on in order for
  2802 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2803 usually the case when using Proof General with the default settings).
  2804 
  2805 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2806 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2807 duplicate fact bindings, or even accidental fact duplications.  Note
  2808 that tools may maintain dynamically scoped facts systematically, using
  2809 PureThy.add_thms_dynamic.
  2810 
  2811 * Command 'hide' now allows to hide from "fact" name space as well.
  2812 
  2813 * Eliminated destructive theorem database, simpset, claset, and
  2814 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2815 update of theories within ML code.
  2816 
  2817 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2818 INCOMPATIBILITY, object-logics depending on former Pure require
  2819 additional setup PureThy.old_appl_syntax_setup; object-logics
  2820 depending on former CPure need to refer to Pure.
  2821 
  2822 * Commands 'use' and 'ML' are now purely functional, operating on
  2823 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2824 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2825 INCOMPATIBILITY.
  2826 
  2827 * Command 'setup': discontinued implicit version with ML reference.
  2828 
  2829 * Instantiation target allows for simultaneous specification of class
  2830 instance operations together with an instantiation proof.
  2831 Type-checking phase allows to refer to class operations uniformly.
  2832 See src/HOL/Complex/Complex.thy for an Isar example and
  2833 src/HOL/Library/Eval.thy for an ML example.
  2834 
  2835 * Indexing of literal facts: be more serious about including only
  2836 facts from the visible specification/proof context, but not the
  2837 background context (locale etc.).  Affects `prop` notation and method
  2838 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2839 situations.
  2840 
  2841 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2842 "(open)" option, which used to expose internal bound variables to the
  2843 proof text.
  2844 
  2845 * Isar statements: removed obsolete case "rule_context".
  2846 INCOMPATIBILITY, better use explicit fixes/assumes.
  2847 
  2848 * Locale proofs: default proof step now includes 'unfold_locales';
  2849 hence 'proof' without argument may be used to unfold locale
  2850 predicates.
  2851 
  2852 
  2853 *** Document preparation ***
  2854 
  2855 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2856 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2857 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2858 spot); renamed link color from "darkblue" to "linkcolor" (default
  2859 value unchanged, can be redefined via \definecolor); no longer sets
  2860 "a4paper" option (unnecessary or even intrusive).
  2861 
  2862 * Antiquotation @{lemma A method} proves proposition A by the given
  2863 method (either a method name or a method name plus (optional) method
  2864 arguments in parentheses) and prints A just like @{prop A}.
  2865 
  2866 
  2867 *** HOL ***
  2868 
  2869 * New primrec package.  Specification syntax conforms in style to
  2870 definition/function/....  No separate induction rule is provided.  The
  2871 "primrec" command distinguishes old-style and new-style specifications
  2872 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2873 When adjusting theories, beware: constants stemming from new-style
  2874 primrec specifications have authentic syntax.
  2875 
  2876 * Metis prover is now an order of magnitude faster, and also works
  2877 with multithreading.
  2878 
  2879 * Metis: the maximum number of clauses that can be produced from a
  2880 theorem is now given by the attribute max_clauses.  Theorems that
  2881 exceed this number are ignored, with a warning printed.
  2882 
  2883 * Sledgehammer no longer produces structured proofs by default. To
  2884 enable, declare [[sledgehammer_full = true]].  Attributes
  2885 reconstruction_modulus, reconstruction_sorts renamed
  2886 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2887 
  2888 * Method "induct_scheme" derives user-specified induction rules
  2889 from well-founded induction and completeness of patterns. This factors
  2890 out some operations that are done internally by the function package
  2891 and makes them available separately.  See
  2892 src/HOL/ex/Induction_Scheme.thy for examples.
  2893 
  2894 * More flexible generation of measure functions for termination
  2895 proofs: Measure functions can be declared by proving a rule of the
  2896 form "is_measure f" and giving it the [measure_function] attribute.
  2897 The "is_measure" predicate is logically meaningless (always true), and
  2898 just guides the heuristic.  To find suitable measure functions, the
  2899 termination prover sets up the goal "is_measure ?f" of the appropriate
  2900 type and generates all solutions by prolog-style backwards proof using
  2901 the declared rules.
  2902 
  2903 This setup also deals with rules like 
  2904 
  2905   "is_measure f ==> is_measure (list_size f)"
  2906 
  2907 which accommodates nested datatypes that recurse through lists.
  2908 Similar rules are predeclared for products and option types.
  2909 
  2910 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  2911 
  2912   INCOMPATIBILITIES:
  2913 
  2914   - Definitions of overloaded constants on sets have to be replaced by
  2915     definitions on => and bool.
  2916 
  2917   - Some definitions of overloaded operators on sets can now be proved
  2918     using the definitions of the operators on => and bool.  Therefore,
  2919     the following theorems have been renamed:
  2920 
  2921       subset_def   -> subset_eq
  2922       psubset_def  -> psubset_eq
  2923       set_diff_def -> set_diff_eq
  2924       Compl_def    -> Compl_eq
  2925       Sup_set_def  -> Sup_set_eq
  2926       Inf_set_def  -> Inf_set_eq
  2927       sup_set_def  -> sup_set_eq
  2928       inf_set_def  -> inf_set_eq
  2929 
  2930   - Due to the incompleteness of the HO unification algorithm, some
  2931     rules such as subst may require manual instantiation, if some of
  2932     the unknowns in the rule is a set.
  2933 
  2934   - Higher order unification and forward proofs:
  2935     The proof pattern
  2936 
  2937       have "P (S::'a set)" <...>
  2938       then have "EX S. P S" ..
  2939 
  2940     no longer works (due to the incompleteness of the HO unification
  2941     algorithm) and must be replaced by the pattern
  2942 
  2943       have "EX S. P S"
  2944       proof
  2945         show "P S" <...>
  2946       qed
  2947 
  2948   - Calculational reasoning with subst (or similar rules):
  2949     The proof pattern
  2950 
  2951       have "P (S::'a set)" <...>
  2952       also have "S = T" <...>
  2953       finally have "P T" .
  2954 
  2955     no longer works (for similar reasons as the previous example) and
  2956     must be replaced by something like
  2957 
  2958       have "P (S::'a set)" <...>
  2959       moreover have "S = T" <...>
  2960       ultimately have "P T" by simp
  2961 
  2962   - Tactics or packages written in ML code:
  2963     Code performing pattern matching on types via
  2964 
  2965       Type ("set", [T]) => ...
  2966 
  2967     must be rewritten. Moreover, functions like strip_type or
  2968     binder_types no longer return the right value when applied to a
  2969     type of the form
  2970 
  2971       T1 => ... => Tn => U => bool
  2972 
  2973     rather than
  2974 
  2975       T1 => ... => Tn => U set
  2976 
  2977 * Merged theories Wellfounded_Recursion, Accessible_Part and
  2978 Wellfounded_Relations to theory Wellfounded.
  2979 
  2980 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  2981 
  2982 * Class finite no longer treats UNIV as class parameter.  Use class
  2983 enum from theory Library/Enum instead to achieve a similar effect.
  2984 INCOMPATIBILITY.
  2985 
  2986 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  2987 and "Cons".  INCOMPATIBILITY.
  2988 
  2989 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  2990 Potential INCOMPATIBILITY.
  2991 
  2992 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  2993 injective_fst_snd removed, use split_eta and prod_eqI instead.
  2994 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  2995 
  2996 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  2997 the same name in theory Orderings:
  2998 
  2999   less_trans
  3000   less_linear
  3001   le_imp_less_or_eq
  3002   le_less_trans
  3003   less_le_trans
  3004   less_not_sym
  3005   less_asym
  3006 
  3007 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  3008 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  3009 and different variable names.
  3010 
  3011 * Library/Option_ord.thy: Canonical order on option type.
  3012 
  3013 * Library/RBT.thy: Red-black trees, an efficient implementation of
  3014 finite maps.
  3015 
  3016 * Library/Countable.thy: Type class for countable types.
  3017 
  3018 * Theory Int: The representation of numerals has changed.  The infix
  3019 operator BIT and the bit datatype with constructors B0 and B1 have
  3020 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  3021 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  3022 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  3023 accordingly.
  3024 
  3025 * Theory Nat: definition of <= and < on natural numbers no longer
  3026 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  3027 le_def and less_def have disappeared.  Consider lemmas not_less
  3028 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  3029 
  3030 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  3031 (whose purpose mainly is for various fold_set functionals) have been
  3032 abandoned in favor of the existing algebraic classes
  3033 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  3034 lower_semilattice (resp. upper_semilattice) and linorder.
  3035 INCOMPATIBILITY.
  3036 
  3037 * Theory Transitive_Closure: induct and cases rules now declare proper
  3038 case_names ("base" and "step").  INCOMPATIBILITY.
  3039 
  3040 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  3041 lattices.  The form set-specific version is available as
  3042 Inductive.lfp_ordinal_induct_set.
  3043 
  3044 * Renamed theorems "power.simps" to "power_int.simps".
  3045 INCOMPATIBILITY.
  3046 
  3047 * Class semiring_div provides basic abstract properties of semirings
  3048 with division and modulo operations.  Subsumes former class dvd_mod.
  3049 
  3050 * Merged theories IntDef, Numeral and IntArith into unified theory
  3051 Int.  INCOMPATIBILITY.
  3052 
  3053 * Theory Library/Code_Index: type "index" now represents natural
  3054 numbers rather than integers.  INCOMPATIBILITY.
  3055 
  3056 * New class "uminus" with operation "uminus" (split of from class
  3057 "minus" which now only has operation "minus", binary).
  3058 INCOMPATIBILITY.
  3059 
  3060 * Constants "card", "internal_split", "option_map" now with authentic
  3061 syntax.  INCOMPATIBILITY.
  3062 
  3063 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  3064 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  3065 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  3066 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  3067 Sup_set_def, le_def, less_def, option_map_def now with object
  3068 equality.  INCOMPATIBILITY.
  3069 
  3070 * Records. Removed K_record, and replaced it by pure lambda term
  3071 %x. c. The simplifier setup is now more robust against eta expansion.
  3072 INCOMPATIBILITY: in cases explicitly referring to K_record.
  3073 
  3074 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  3075 
  3076 * Library/ListVector: new theory of arithmetic vector operations.
  3077 
  3078 * Library/Order_Relation: new theory of various orderings as sets of
  3079 pairs.  Defines preorders, partial orders, linear orders and
  3080 well-orders on sets and on types.
  3081 
  3082 
  3083 *** ZF ***
  3084 
  3085 * Renamed some theories to allow to loading both ZF and HOL in the
  3086 same session:
  3087 
  3088   Datatype  -> Datatype_ZF
  3089   Inductive -> Inductive_ZF
  3090   Int       -> Int_ZF
  3091   IntDiv    -> IntDiv_ZF
  3092   Nat       -> Nat_ZF
  3093   List      -> List_ZF
  3094   Main      -> Main_ZF
  3095 
  3096 INCOMPATIBILITY: ZF theories that import individual theories below
  3097 Main might need to be adapted.  Regular theory Main is still
  3098 available, as trivial extension of Main_ZF.
  3099 
  3100 
  3101 *** ML ***
  3102 
  3103 * ML within Isar: antiquotation @{const name} or @{const
  3104 name(typargs)} produces statically-checked Const term.
  3105 
  3106 * Functor NamedThmsFun: data is available to the user as dynamic fact
  3107 (of the same name).  Removed obsolete print command.
  3108 
  3109 * Removed obsolete "use_legacy_bindings" function.
  3110 
  3111 * The ``print mode'' is now a thread-local value derived from a global
  3112 template (the former print_mode reference), thus access becomes
  3113 non-critical.  The global print_mode reference is for session
  3114 management only; user-code should use print_mode_value,
  3115 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  3116 
  3117 * Functions system/system_out provide a robust way to invoke external
  3118 shell commands, with propagation of interrupts (requires Poly/ML
  3119 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  3120 
  3121 
  3122 *** System ***
  3123 
  3124 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  3125 in accordance with Proof General 3.7, which prefers GNU emacs.
  3126 
  3127 * isatool tty runs Isabelle process with plain tty interaction;
  3128 optional line editor may be specified via ISABELLE_LINE_EDITOR
  3129 setting, the default settings attempt to locate "ledit" and "rlwrap".
  3130 
  3131 * isatool browser now works with Cygwin as well, using general
  3132 "javapath" function defined in Isabelle process environment.
  3133 
  3134 * YXML notation provides a simple and efficient alternative to
  3135 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  3136 isatool yxml as described in the Isabelle system manual.
  3137 
  3138 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  3139 provides general wrapper for managing an Isabelle process in a robust
  3140 fashion, with ``cooked'' output from stdin/stderr.
  3141 
  3142 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  3143 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  3144 
  3145 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  3146 way of changing the user's settings is via
  3147 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  3148 script.
  3149 
  3150 * Multithreading.max_threads := 0 refers to the number of actual CPU
  3151 cores of the underlying machine, which is a good starting point for
  3152 optimal performance tuning.  The corresponding usedir option -M allows
  3153 "max" as an alias for "0".  WARNING: does not work on certain versions
  3154 of Mac OS (with Poly/ML 5.1).
  3155 
  3156 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  3157 adverse effect of Isabelle flooding interactive front-ends (notably
  3158 ProofGeneral / XEmacs).
  3159 
  3160 
  3161 
  3162 New in Isabelle2007 (November 2007)
  3163 -----------------------------------
  3164 
  3165 *** General ***
  3166 
  3167 * More uniform information about legacy features, notably a
  3168 warning/error of "Legacy feature: ...", depending on the state of the
  3169 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  3170 legacy features will disappear eventually.
  3171 
  3172 * Theory syntax: the header format ``theory A = B + C:'' has been
  3173 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  3174 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  3175 
  3176 * Theory syntax: the old non-Isar theory file format has been
  3177 discontinued altogether.  Note that ML proof scripts may still be used
  3178 with Isar theories; migration is usually quite simple with the ML
  3179 function use_legacy_bindings.  INCOMPATIBILITY.
  3180 
  3181 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  3182 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  3183 quotes.
  3184 
  3185 * Theory loader: be more serious about observing the static theory
  3186 header specifications (including optional directories), but not the
  3187 accidental file locations of previously successful loads.  The strict
  3188 update policy of former update_thy is now already performed by
  3189 use_thy, so the former has been removed; use_thys updates several
  3190 theories simultaneously, just as 'imports' within a theory header
  3191 specification, but without merging the results.  Potential
  3192 INCOMPATIBILITY: may need to refine theory headers and commands
  3193 ROOT.ML which depend on load order.
  3194 
  3195 * Theory loader: optional support for content-based file
  3196 identification, instead of the traditional scheme of full physical
  3197 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  3198 (cf. the system manual).  The new scheme allows to work with
  3199 non-finished theories in persistent session images, such that source
  3200 files may be moved later on without requiring reloads.
  3201 
  3202 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3203 file (with the same base name as the theory) are considered a legacy
  3204 feature, which will disappear eventually. Even now, the theory loader
  3205 no longer maintains dependencies on such files.
  3206 
  3207 * Syntax: the scope for resolving ambiguities via type-inference is
  3208 now limited to individual terms, instead of whole simultaneous
  3209 specifications as before. This greatly reduces the complexity of the
  3210 syntax module and improves flexibility by separating parsing and
  3211 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  3212 'fixes' etc.) are required in rare situations.
  3213 
  3214 * Syntax: constants introduced by new-style packages ('definition',
  3215 'abbreviation' etc.) are passed through the syntax module in
  3216 ``authentic mode''. This means that associated mixfix annotations
  3217 really stick to such constants, independently of potential name space
  3218 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  3219 trees are represented slightly differently, may need to adapt syntax
  3220 translations accordingly. Use CONST marker in 'translations' and
  3221 @{const_syntax} antiquotation in 'parse_translation' etc.
  3222 
  3223 * Legacy goal package: reduced interface to the bare minimum required
  3224 to keep existing proof scripts running.  Most other user-level
  3225 functions are now part of the OldGoals structure, which is *not* open
  3226 by default (consider isatool expandshort before open OldGoals).
  3227 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  3228 these tend to cause confusion about the actual goal (!) context being
  3229 used here, which is not necessarily the same as the_context().
  3230 
  3231 * Command 'find_theorems': supports "*" wild-card in "name:"
  3232 criterion; "with_dups" option.  Certain ProofGeneral versions might
  3233 support a specific search form (see ProofGeneral/CHANGES).
  3234 
  3235 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  3236 by default, which means that "prems" (and also "fixed variables") are
  3237 suppressed from proof state output.  Note that the ProofGeneral
  3238 settings mechanism allows to change and save options persistently, but
  3239 older versions of Isabelle will fail to start up if a negative prems
  3240 limit is imposed.
  3241 
  3242 * Local theory targets may be specified by non-nested blocks of
  3243 ``context/locale/class ... begin'' followed by ``end''.  The body may
  3244 contain definitions, theorems etc., including any derived mechanism
  3245 that has been implemented on top of these primitives.  This concept
  3246 generalizes the existing ``theorem (in ...)'' towards more versatility
  3247 and scalability.
  3248 
  3249 * Proof General interface: proper undo of final 'end' command;
  3250 discontinued Isabelle/classic mode (ML proof scripts).
  3251 
  3252 
  3253 *** Document preparation ***
  3254 
  3255 * Added antiquotation @{theory name} which prints the given name,
  3256 after checking that it refers to a valid ancestor theory in the
  3257 current context.
  3258 
  3259 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  3260 check the given source text as ML type/structure, printing verbatim.
  3261 
  3262 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  3263 "c args == rhs" given in the current context.  (Any number of
  3264 arguments may be given on the LHS.)
  3265 
  3266 
  3267 *** Pure ***
  3268 
  3269 * The 'class' package offers a combination of axclass and locale to
  3270 achieve Haskell-like type classes in Isabelle.  Definitions and
  3271 theorems within a class context produce both relative results (with
  3272 implicit parameters according to the locale context), and polymorphic
  3273 constants with qualified polymorphism (according to the class
  3274 context).  Within the body context of a 'class' target, a separate
  3275 syntax layer ("user space type system") takes care of converting
  3276 between global polymorphic consts and internal locale representation.
  3277 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  3278 "isatool doc classes" provides a tutorial.
  3279 
  3280 * Generic code generator framework allows to generate executable
  3281 code for ML and Haskell (including Isabelle classes).  A short usage
  3282 sketch:
  3283 
  3284     internal compilation:
  3285         export_code <list of constants (term syntax)> in SML
  3286     writing SML code to a file:
  3287         export_code <list of constants (term syntax)> in SML <filename>
  3288     writing OCaml code to a file:
  3289         export_code <list of constants (term syntax)> in OCaml <filename>
  3290     writing Haskell code to a bunch of files:
  3291         export_code <list of constants (term syntax)> in Haskell <filename>
  3292 
  3293     evaluating closed propositions to True/False using code generation:
  3294         method ``eval''
  3295 
  3296 Reasonable default setup of framework in HOL.
  3297 
  3298 Theorem attributs for selecting and transforming function equations theorems:
  3299 
  3300     [code fun]:        select a theorem as function equation for a specific constant
  3301     [code fun del]:    deselect a theorem as function equation for a specific constant
  3302     [code inline]:     select an equation theorem for unfolding (inlining) in place
  3303     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  3304 
  3305 User-defined serializations (target in {SML, OCaml, Haskell}):
  3306 
  3307     code_const <and-list of constants (term syntax)>
  3308       {(target) <and-list of const target syntax>}+
  3309 
  3310     code_type <and-list of type constructors>
  3311       {(target) <and-list of type target syntax>}+
  3312 
  3313     code_instance <and-list of instances>
  3314       {(target)}+
  3315         where instance ::= <type constructor> :: <class>
  3316 
  3317     code_class <and_list of classes>
  3318       {(target) <and-list of class target syntax>}+
  3319         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  3320 
  3321 code_instance and code_class only are effective to target Haskell.
  3322 
  3323 For example usage see src/HOL/ex/Codegenerator.thy and
  3324 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  3325 generation from Isabelle/HOL theories is available via "isatool doc
  3326 codegen".
  3327 
  3328 * Code generator: consts in 'consts_code' Isar commands are now
  3329 referred to by usual term syntax (including optional type
  3330 annotations).
  3331 
  3332 * Command 'no_translations' removes translation rules from theory
  3333 syntax.
  3334 
  3335 * Overloaded definitions are now actually checked for acyclic
  3336 dependencies.  The overloading scheme is slightly more general than
  3337 that of Haskell98, although Isabelle does not demand an exact
  3338 correspondence to type class and instance declarations.
  3339 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  3340 exotic versions of overloading -- at the discretion of the user!
  3341 
  3342 Polymorphic constants are represented via type arguments, i.e. the
  3343 instantiation that matches an instance against the most general
  3344 declaration given in the signature.  For example, with the declaration
  3345 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  3346 as c(nat).  Overloading is essentially simultaneous structural
  3347 recursion over such type arguments.  Incomplete specification patterns
  3348 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  3349 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  3350 Command 'print_theory' outputs the normalized system of recursive
  3351 equations, see section "definitions".
  3352 
  3353 * Configuration options are maintained within the theory or proof
  3354 context (with name and type bool/int/string), providing a very simple
  3355 interface to a poor-man's version of general context data.  Tools may
  3356 declare options in ML (e.g. using Attrib.config_int) and then refer to
  3357 these values using Config.get etc.  Users may change options via an
  3358 associated attribute of the same name.  This form of context
  3359 declaration works particularly well with commands 'declare' or
  3360 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  3361 very easy to avoid global references, which would not observe Isar
  3362 toplevel undo/redo and fail to work with multithreading.
  3363 
  3364 Various global ML references of Pure and HOL have been turned into
  3365 configuration options:
  3366 
  3367   Unify.search_bound		unify_search_bound
  3368   Unify.trace_bound		unify_trace_bound
  3369   Unify.trace_simp		unify_trace_simp
  3370   Unify.trace_types		unify_trace_types
  3371   Simplifier.simp_depth_limit	simp_depth_limit
  3372   Blast.depth_limit		blast_depth_limit
  3373   DatatypeProp.dtK		datatype_distinctness_limit
  3374   fast_arith_neq_limit  	fast_arith_neq_limit
  3375   fast_arith_split_limit	fast_arith_split_limit
  3376 
  3377 * Named collections of theorems may be easily installed as context
  3378 data using the functor NamedThmsFun (see also
  3379 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  3380 attributes; there is also a toplevel print command.  This facility is
  3381 just a common case of general context data, which is the preferred way
  3382 for anything more complex than just a list of facts in canonical
  3383 order.
  3384 
  3385 * Isar: command 'declaration' augments a local theory by generic
  3386 declaration functions written in ML.  This enables arbitrary content
  3387 being added to the context, depending on a morphism that tells the
  3388 difference of the original declaration context wrt. the application
  3389 context encountered later on.
  3390 
  3391 * Isar: proper interfaces for simplification procedures.  Command
  3392 'simproc_setup' declares named simprocs (with match patterns, and body
  3393 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  3394 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  3395 
  3396 * Isar: an extra pair of brackets around attribute declarations
  3397 abbreviates a theorem reference involving an internal dummy fact,
  3398 which will be ignored later --- only the effect of the attribute on
  3399 the background context will persist.  This form of in-place
  3400 declarations is particularly useful with commands like 'declare' and
  3401 'using', for example ``have A using [[simproc a]] by simp''.
  3402 
  3403 * Isar: method "assumption" (and implicit closing of subproofs) now
  3404 takes simple non-atomic goal assumptions into account: after applying
  3405 an assumption as a rule the resulting subgoals are solved by atomic
  3406 assumption steps.  This is particularly useful to finish 'obtain'
  3407 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  3408 without referring to the original premise "!!x. P x ==> thesis" in the
  3409 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  3410 more permissive.
  3411 
  3412 * Isar: implicit use of prems from the Isar proof context is
  3413 considered a legacy feature.  Common applications like ``have A .''
  3414 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  3415 referencing facts explicitly here improves readability and
  3416 maintainability of proof texts.
  3417 
  3418 * Isar: improper proof element 'guess' is like 'obtain', but derives
  3419 the obtained context from the course of reasoning!  For example:
  3420 
  3421   assume "EX x y. A x & B y"   -- "any previous fact"
  3422   then guess x and y by clarify
  3423 
  3424 This technique is potentially adventurous, depending on the facts and
  3425 proof tools being involved here.
  3426 
  3427 * Isar: known facts from the proof context may be specified as literal
  3428 propositions, using ASCII back-quote syntax.  This works wherever
  3429 named facts used to be allowed so far, in proof commands, proof
  3430 methods, attributes etc.  Literal facts are retrieved from the context
  3431 according to unification of type and term parameters.  For example,
  3432 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  3433 theorems in the current context, then these are valid literal facts:
  3434 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  3435 
  3436 There is also a proof method "fact" which does the same composition
  3437 for explicit goal states, e.g. the following proof texts coincide with
  3438 certain special cases of literal facts:
  3439 
  3440   have "A" by fact                 ==  note `A`
  3441   have "A ==> B" by fact           ==  note `A ==> B`
  3442   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  3443   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  3444 
  3445 * Isar: ":" (colon) is no longer a symbolic identifier character in
  3446 outer syntax.  Thus symbolic identifiers may be used without
  3447 additional white space in declarations like this: ``assume *: A''.
  3448 
  3449 * Isar: 'print_facts' prints all local facts of the current context,
  3450 both named and unnamed ones.
  3451 
  3452 * Isar: 'def' now admits simultaneous definitions, e.g.:
  3453 
  3454   def x == "t" and y == "u"
  3455 
  3456 * Isar: added command 'unfolding', which is structurally similar to
  3457 'using', but affects both the goal state and facts by unfolding given
  3458 rewrite rules.  Thus many occurrences of the 'unfold' method or
  3459 'unfolded' attribute may be replaced by first-class proof text.
  3460 
  3461 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  3462 and command 'unfolding' now all support object-level equalities
  3463 (potentially conditional).  The underlying notion of rewrite rule is
  3464 analogous to the 'rule_format' attribute, but *not* that of the
  3465 Simplifier (which is usually more generous).
  3466 
  3467 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  3468 premises of a theorem by n. Useful in conjunction with drule.
  3469 
  3470 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  3471 method expression within a sandbox consisting of the first N
  3472 sub-goals, which need to exist.  For example, ``simp_all [3]''
  3473 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  3474 simplifies all new goals that emerge from applying rule foo to the
  3475 originally first one.
  3476 
  3477 * Isar: schematic goals are no longer restricted to higher-order
  3478 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  3479 expected.
  3480 
  3481 * Isar: the conclusion of a long theorem statement is now either
  3482 'shows' (a simultaneous conjunction, as before), or 'obtains'
  3483 (essentially a disjunction of cases with local parameters and
  3484 assumptions).  The latter allows to express general elimination rules
  3485 adequately; in this notation common elimination rules look like this:
  3486 
  3487   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  3488     assumes "EX x. P x"
  3489     obtains x where "P x"
  3490 
  3491   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  3492     assumes "A & B"
  3493     obtains A and B
  3494 
  3495   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  3496     assumes "A | B"
  3497     obtains
  3498       A
  3499     | B
  3500 
  3501 The subsequent classical rules even refer to the formal "thesis"
  3502 explicitly:
  3503 
  3504   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  3505     obtains "~ thesis"
  3506 
  3507   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  3508     obtains "thesis ==> something"
  3509 
  3510 The actual proof of an 'obtains' statement is analogous to that of the
  3511 Isar proof element 'obtain', only that there may be several cases.
  3512 Optional case names may be specified in parentheses; these will be
  3513 available both in the present proof and as annotations in the
  3514 resulting rule, for later use with the 'cases' method (cf. attribute
  3515 case_names).
  3516 
  3517 * Isar: the assumptions of a long theorem statement are available as
  3518 "assms" fact in the proof context.  This is more appropriate than the
  3519 (historical) "prems", which refers to all assumptions of the current
  3520 context, including those from the target locale, proof body etc.
  3521 
  3522 * Isar: 'print_statement' prints theorems from the current theory or
  3523 proof context in long statement form, according to the syntax of a
  3524 top-level lemma.
  3525 
  3526 * Isar: 'obtain' takes an optional case name for the local context
  3527 introduction rule (default "that").
  3528 
  3529 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  3530 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  3531 to occur.
  3532 
  3533 * Pure: syntax "CONST name" produces a fully internalized constant
  3534 according to the current context.  This is particularly useful for
  3535 syntax translations that should refer to internal constant
  3536 representations independently of name spaces.
  3537 
  3538 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  3539 instead of "FOO ". This allows multiple binder declarations to coexist
  3540 in the same context.  INCOMPATIBILITY.
  3541 
  3542 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  3543 primitive that also works in a locale context (both for constants and
  3544 fixed variables). Type declaration and internal syntactic representation
  3545 of given constants retrieved from the context. Likewise, the
  3546 'no_notation' command allows to remove given syntax annotations from the
  3547 current context.
  3548 
  3549 * Isar/locales: new derived specification elements 'axiomatization',
  3550 'definition', 'abbreviation', which support type-inference, admit
  3551 object-level specifications (equality, equivalence).  See also the
  3552 isar-ref manual.  Examples:
  3553 
  3554   axiomatization
  3555     eq  (infix "===" 50) where
  3556     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  3557 
  3558   definition "f x y = x + y + 1"
  3559   definition g where "g x = f x x"
  3560 
  3561   abbreviation
  3562     neq  (infix "=!=" 50) where
  3563     "x =!= y == ~ (x === y)"
  3564 
  3565 These specifications may be also used in a locale context.  Then the
  3566 constants being introduced depend on certain fixed parameters, and the
  3567 constant name is qualified by the locale base name.  An internal
  3568 abbreviation takes care for convenient input and output, making the
  3569 parameters implicit and using the original short name.  See also
  3570 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  3571 entities from a monomorphic theory.
  3572 
  3573 Presently, abbreviations are only available 'in' a target locale, but
  3574 not inherited by general import expressions.  Also note that
  3575 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  3576 'translations' in common applications.  The "no_abbrevs" print mode
  3577 prevents folding of abbreviations in term output.
  3578 
  3579 Concrete syntax is attached to specified constants in internal form,
  3580 independently of name spaces.  The parse tree representation is
  3581 slightly different -- use 'notation' instead of raw 'syntax', and
  3582 'translations' with explicit "CONST" markup to accommodate this.
  3583 
  3584 * Pure/Isar: unified syntax for new-style specification mechanisms
  3585 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  3586 full type inference and dummy patterns ("_").  For example:
  3587 
  3588   definition "K x _ = x"
  3589 
  3590   inductive conj for A B
  3591   where "A ==> B ==> conj A B"
  3592 
  3593 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  3594 the current context.  Print mode "no_abbrevs" prevents inversion of
  3595 abbreviations on output.
  3596 
  3597 * Isar/locales: improved parameter handling: use of locales "var" and
  3598 "struct" no longer necessary; - parameter renamings are no longer
  3599 required to be injective.  For example, this allows to define
  3600 endomorphisms as locale endom = homom mult mult h.
  3601 
  3602 * Isar/locales: changed the way locales with predicates are defined.
  3603 Instead of accumulating the specification, the imported expression is
  3604 now an interpretation.  INCOMPATIBILITY: different normal form of
  3605 locale expressions.  In particular, in interpretations of locales with
  3606 predicates, goals repesenting already interpreted fragments are not
  3607 removed automatically.  Use methods `intro_locales' and
  3608 `unfold_locales'; see below.
  3609 
  3610 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  3611 provide backward reasoning on locales predicates.  The methods are
  3612 aware of interpretations and discharge corresponding goals.
  3613 `intro_locales' is less aggressive then `unfold_locales' and does not
  3614 unfold predicates to assumptions.
  3615 
  3616 * Isar/locales: the order in which locale fragments are accumulated
  3617 has changed.  This enables to override declarations from fragments due
  3618 to interpretations -- for example, unwanted simp rules.
  3619 
  3620 * Isar/locales: interpretation in theories and proof contexts has been
  3621 extended.  One may now specify (and prove) equations, which are
  3622 unfolded in interpreted theorems.  This is useful for replacing
  3623 defined concepts (constants depending on locale parameters) by
  3624 concepts already existing in the target context.  Example:
  3625 
  3626   interpretation partial_order ["op <= :: [int, int] => bool"]
  3627     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3628 
  3629 Typically, the constant `partial_order.less' is created by a
  3630 definition specification element in the context of locale
  3631 partial_order.
  3632 
  3633 * Method "induct": improved internal context management to support
  3634 local fixes and defines on-the-fly. Thus explicit meta-level
  3635 connectives !!  and ==> are rarely required anymore in inductive goals
  3636 (using object-logic connectives for this purpose has been long
  3637 obsolete anyway). Common proof patterns are explained in
  3638 src/HOL/Induct/Common_Patterns.thy, see also
  3639 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3640 examples.
  3641 
  3642 * Method "induct": improved handling of simultaneous goals. Instead of
  3643 introducing object-level conjunction, the statement is now split into
  3644 several conclusions, while the corresponding symbolic cases are nested
  3645 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3646 see src/HOL/Induct/Common_Patterns.thy, for example.
  3647 
  3648 * Method "induct": mutual induction rules are now specified as a list
  3649 of rule sharing the same induction cases. HOL packages usually provide
  3650 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3651 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3652 mutual induction rules differently, i.e. like this:
  3653 
  3654   (induct rule: foo_bar.inducts)
  3655   (induct set: foo bar)
  3656   (induct pred: foo bar)
  3657   (induct type: foo bar)
  3658 
  3659 The ML function ProjectRule.projections turns old-style rules into the
  3660 new format.
  3661 
  3662 * Method "coinduct": dual of induction, see
  3663 src/HOL/Library/Coinductive_List.thy for various examples.
  3664 
  3665 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3666 considered a legacy feature.
  3667 
  3668 * Attribute "symmetric" produces result with standardized schematic
  3669 variables (index 0).  Potential INCOMPATIBILITY.
  3670 
  3671 * Simplifier: by default the simplifier trace only shows top level
  3672 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3673 default. Thus there is less danger of being flooded by the trace. The
  3674 trace indicates where parts have been suppressed.
  3675   
  3676 * Provers/classical: removed obsolete classical version of elim_format
  3677 attribute; classical elim/dest rules are now treated uniformly when
  3678 manipulating the claset.
  3679 
  3680 * Provers/classical: stricter checks to ensure that supplied intro,
  3681 dest and elim rules are well-formed; dest and elim rules must have at
  3682 least one premise.
  3683 
  3684 * Provers/classical: attributes dest/elim/intro take an optional
  3685 weight argument for the rule (just as the Pure versions).  Weights are
  3686 ignored by automated tools, but determine the search order of single
  3687 rule steps.
  3688 
  3689 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3690 where the body does not mention the bound variable.  Note that dummy
  3691 patterns implicitly depend on their context of bounds, which makes
  3692 "{_. _}" match any set comprehension as expected.  Potential
  3693 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3694 constant "_idtdummy" in the binding position.
  3695 
  3696 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3697 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3698 for example "A -> B" => "Pi A (%_. B)".
  3699 
  3700 * Pure: 'class_deps' command visualizes the subclass relation, using
  3701 the graph browser tool.
  3702 
  3703 * Pure: 'print_theory' now suppresses certain internal declarations by
  3704 default; use '!' option for full details.
  3705 
  3706 
  3707 *** HOL ***
  3708 
  3709 * Method "metis" proves goals by applying the Metis general-purpose
  3710 resolution prover (see also http://gilith.com/software/metis/).
  3711 Examples are in the directory MetisExamples.  WARNING: the
  3712 Isabelle/HOL-Metis integration does not yet work properly with
  3713 multi-threading.
  3714   
  3715 * Command 'sledgehammer' invokes external automatic theorem provers as
  3716 background processes.  It generates calls to the "metis" method if
  3717 successful. These can be pasted into the proof.  Users do not have to
  3718 wait for the automatic provers to return.  WARNING: does not really
  3719 work with multi-threading.
  3720 
  3721 * New "auto_quickcheck" feature tests outermost goal statements for
  3722 potential counter-examples.  Controlled by ML references
  3723 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3724 5000 milliseconds).  Fails silently if statements is outside of
  3725 executable fragment, or any other codgenerator problem occurs.
  3726 
  3727 * New constant "undefined" with axiom "undefined x = undefined".
  3728 
  3729 * Added class "HOL.eq", allowing for code generation with polymorphic
  3730 equality.
  3731 
  3732 * Some renaming of class constants due to canonical name prefixing in
  3733 the new 'class' package:
  3734 
  3735     HOL.abs ~> HOL.abs_class.abs
  3736     HOL.divide ~> HOL.divide_class.divide
  3737     0 ~> HOL.zero_class.zero
  3738     1 ~> HOL.one_class.one
  3739     op + ~> HOL.plus_class.plus
  3740     op - ~> HOL.minus_class.minus
  3741     uminus ~> HOL.minus_class.uminus
  3742     op * ~> HOL.times_class.times
  3743     op < ~> HOL.ord_class.less
  3744     op <= > HOL.ord_class.less_eq
  3745     Nat.power ~> Power.power_class.power
  3746     Nat.size ~> Nat.size_class.size
  3747     Numeral.number_of ~> Numeral.number_class.number_of
  3748     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3749     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3750     Orderings.min ~> Orderings.ord_class.min
  3751     Orderings.max ~> Orderings.ord_class.max
  3752     Divides.op div ~> Divides.div_class.div
  3753     Divides.op mod ~> Divides.div_class.mod
  3754     Divides.op dvd ~> Divides.div_class.dvd
  3755 
  3756 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3757 
  3758 a) User-defined constants using any of the names "plus", "minus",
  3759 "times", "less" or "less_eq". The standard syntax translations for
  3760 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3761 names.
  3762 
  3763 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3764 INCOMPATIBILITY: use more specific names.
  3765 
  3766 c) Permutative equations (e.g. "a + b = b + a")
  3767 Since the change of names also changes the order of terms, permutative
  3768 rewrite rules may get applied in a different order. Experience shows
  3769 that this is rarely the case (only two adaptions in the whole Isabelle
  3770 distribution).  INCOMPATIBILITY: rewrite proofs
  3771 
  3772 d) ML code directly refering to constant names
  3773 This in general only affects hand-written proof tactics, simprocs and
  3774 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3775 Consider using @{const_name} antiquotation.
  3776 
  3777 * New class "default" with associated constant "default".
  3778 
  3779 * Function "sgn" is now overloaded and available on int, real, complex
  3780 (and other numeric types), using class "sgn".  Two possible defs of
  3781 sgn are given as equational assumptions in the classes sgn_if and
  3782 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3783 INCOMPATIBILITY.
  3784 
  3785 * Locale "partial_order" now unified with class "order" (cf. theory
  3786 Orderings), added parameter "less".  INCOMPATIBILITY.
  3787 
  3788 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3789 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3790 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3791 
  3792 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3793 changed order of proof goals in instance proofs.
  3794 
  3795 * The transitivity reasoner for partial and linear orders is set up
  3796 for classes "order" and "linorder".  Instances of the reasoner are available
  3797 in all contexts importing or interpreting the corresponding locales.
  3798 Method "order" invokes the reasoner separately; the reasoner
  3799 is also integrated with the Simplifier as a solver.  Diagnostic
  3800 command 'print_orders' shows the available instances of the reasoner
  3801 in the current context.
  3802 
  3803 * Localized monotonicity predicate in theory "Orderings"; integrated
  3804 lemmas max_of_mono and min_of_mono with this predicate.
  3805 INCOMPATIBILITY.
  3806 
  3807 * Formulation of theorem "dense" changed slightly due to integration
  3808 with new class dense_linear_order.
  3809 
  3810 * Uniform lattice theory development in HOL.
  3811 
  3812     constants "meet" and "join" now named "inf" and "sup"
  3813     constant "Meet" now named "Inf"
  3814 
  3815     classes "meet_semilorder" and "join_semilorder" now named
  3816       "lower_semilattice" and "upper_semilattice"
  3817     class "lorder" now named "lattice"
  3818     class "comp_lat" now named "complete_lattice"
  3819 
  3820     Instantiation of lattice classes allows explicit definitions
  3821     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3822 
  3823   INCOMPATIBILITY.  Theorem renames:
  3824 
  3825     meet_left_le            ~> inf_le1
  3826     meet_right_le           ~> inf_le2
  3827     join_left_le            ~> sup_ge1
  3828     join_right_le           ~> sup_ge2
  3829     meet_join_le            ~> inf_sup_ord
  3830     le_meetI                ~> le_infI
  3831     join_leI                ~> le_supI
  3832     le_meet                 ~> le_inf_iff
  3833     le_join                 ~> ge_sup_conv
  3834     meet_idempotent         ~> inf_idem
  3835     join_idempotent         ~> sup_idem
  3836     meet_comm               ~> inf_commute
  3837     join_comm               ~> sup_commute
  3838     meet_leI1               ~> le_infI1
  3839     meet_leI2               ~> le_infI2
  3840     le_joinI1               ~> le_supI1
  3841     le_joinI2               ~> le_supI2
  3842     meet_assoc              ~> inf_assoc
  3843     join_assoc              ~> sup_assoc
  3844     meet_left_comm          ~> inf_left_commute
  3845     meet_left_idempotent    ~> inf_left_idem
  3846     join_left_comm          ~> sup_left_commute
  3847     join_left_idempotent    ~> sup_left_idem
  3848     meet_aci                ~> inf_aci
  3849     join_aci                ~> sup_aci
  3850     le_def_meet             ~> le_iff_inf
  3851     le_def_join             ~> le_iff_sup
  3852     join_absorp2            ~> sup_absorb2
  3853     join_absorp1            ~> sup_absorb1
  3854     meet_absorp1            ~> inf_absorb1
  3855     meet_absorp2            ~> inf_absorb2
  3856     meet_join_absorp        ~> inf_sup_absorb
  3857     join_meet_absorp        ~> sup_inf_absorb
  3858     distrib_join_le         ~> distrib_sup_le
  3859     distrib_meet_le         ~> distrib_inf_le
  3860 
  3861     add_meet_distrib_left   ~> add_inf_distrib_left
  3862     add_join_distrib_left   ~> add_sup_distrib_left
  3863     is_join_neg_meet        ~> is_join_neg_inf
  3864     is_meet_neg_join        ~> is_meet_neg_sup
  3865     add_meet_distrib_right  ~> add_inf_distrib_right
  3866     add_join_distrib_right  ~> add_sup_distrib_right
  3867     add_meet_join_distribs  ~> add_sup_inf_distribs
  3868     join_eq_neg_meet        ~> sup_eq_neg_inf
  3869     meet_eq_neg_join        ~> inf_eq_neg_sup
  3870     add_eq_meet_join        ~> add_eq_inf_sup
  3871     meet_0_imp_0            ~> inf_0_imp_0
  3872     join_0_imp_0            ~> sup_0_imp_0
  3873     meet_0_eq_0             ~> inf_0_eq_0
  3874     join_0_eq_0             ~> sup_0_eq_0
  3875     neg_meet_eq_join        ~> neg_inf_eq_sup
  3876     neg_join_eq_meet        ~> neg_sup_eq_inf
  3877     join_eq_if              ~> sup_eq_if
  3878 
  3879     mono_meet               ~> mono_inf
  3880     mono_join               ~> mono_sup
  3881     meet_bool_eq            ~> inf_bool_eq
  3882     join_bool_eq            ~> sup_bool_eq
  3883     meet_fun_eq             ~> inf_fun_eq
  3884     join_fun_eq             ~> sup_fun_eq
  3885     meet_set_eq             ~> inf_set_eq
  3886     join_set_eq             ~> sup_set_eq
  3887     meet1_iff               ~> inf1_iff
  3888     meet2_iff               ~> inf2_iff
  3889     meet1I                  ~> inf1I
  3890     meet2I                  ~> inf2I
  3891     meet1D1                 ~> inf1D1
  3892     meet2D1                 ~> inf2D1
  3893     meet1D2                 ~> inf1D2
  3894     meet2D2                 ~> inf2D2
  3895     meet1E                  ~> inf1E
  3896     meet2E                  ~> inf2E
  3897     join1_iff               ~> sup1_iff
  3898     join2_iff               ~> sup2_iff
  3899     join1I1                 ~> sup1I1
  3900     join2I1                 ~> sup2I1
  3901     join1I1                 ~> sup1I1
  3902     join2I2                 ~> sup1I2
  3903     join1CI                 ~> sup1CI
  3904     join2CI                 ~> sup2CI
  3905     join1E                  ~> sup1E
  3906     join2E                  ~> sup2E
  3907 
  3908     is_meet_Meet            ~> is_meet_Inf
  3909     Meet_bool_def           ~> Inf_bool_def
  3910     Meet_fun_def            ~> Inf_fun_def
  3911     Meet_greatest           ~> Inf_greatest
  3912     Meet_lower              ~> Inf_lower
  3913     Meet_set_def            ~> Inf_set_def
  3914 
  3915     Sup_def                 ~> Sup_Inf
  3916     Sup_bool_eq             ~> Sup_bool_def
  3917     Sup_fun_eq              ~> Sup_fun_def
  3918     Sup_set_eq              ~> Sup_set_def
  3919 
  3920     listsp_meetI            ~> listsp_infI
  3921     listsp_meet_eq          ~> listsp_inf_eq
  3922 
  3923     meet_min                ~> inf_min
  3924     join_max                ~> sup_max
  3925 
  3926 * Added syntactic class "size"; overloaded constant "size" now has
  3927 type "'a::size ==> bool"
  3928 
  3929 * Internal reorganisation of `size' of datatypes: size theorems
  3930 "foo.size" are no longer subsumed by "foo.simps" (but are still
  3931 simplification rules by default!); theorems "prod.size" now named
  3932 "*.size".
  3933 
  3934 * Class "div" now inherits from class "times" rather than "type".
  3935 INCOMPATIBILITY.
  3936 
  3937 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  3938 Linorder etc.  have disappeared; operations defined in terms of
  3939 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  3940 
  3941 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  3942 
  3943 * HOL-Word: New extensive library and type for generic, fixed size
  3944 machine words, with arithemtic, bit-wise, shifting and rotating
  3945 operations, reflection into int, nat, and bool lists, automation for
  3946 linear arithmetic (by automatic reflection into nat or int), including
  3947 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  3948 arithmetic type classes, supporting automatic simplification of
  3949 numerals on all operations.
  3950 
  3951 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  3952 
  3953 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  3954 
  3955 * Code generator library theories:
  3956   - Code_Integer represents HOL integers by big integer literals in target
  3957     languages.
  3958   - Code_Char represents HOL characters by character literals in target
  3959     languages.
  3960   - Code_Char_chr like Code_Char, but also offers treatment of character
  3961     codes; includes Code_Integer.
  3962   - Executable_Set allows to generate code for finite sets using lists.
  3963   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  3964     denominator).
  3965   - Executable_Real implements a subset of real numbers, namly those
  3966     representable by rational numbers.
  3967   - Efficient_Nat implements natural numbers by integers, which in general will
  3968     result in higher efficency; pattern matching with 0/Suc is eliminated;
  3969     includes Code_Integer.
  3970   - Code_Index provides an additional datatype index which is mapped to
  3971     target-language built-in integers.
  3972   - Code_Message provides an additional datatype message_string which is isomorphic to
  3973     strings; messages are mapped to target-language strings.
  3974 
  3975 * New package for inductive predicates
  3976 
  3977   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  3978 
  3979     inductive
  3980       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3981       for z_1 :: U_1 and ... and z_n :: U_m
  3982     where
  3983       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3984     | ...
  3985 
  3986   with full support for type-inference, rather than
  3987 
  3988     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3989 
  3990     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3991     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3992 
  3993     inductive "s z_1 ... z_m"
  3994     intros
  3995       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3996       ...
  3997 
  3998   For backward compatibility, there is a wrapper allowing inductive
  3999   sets to be defined with the new package via
  4000 
  4001     inductive_set
  4002       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4003       for z_1 :: U_1 and ... and z_n :: U_m
  4004     where
  4005       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4006     | ...
  4007 
  4008   or
  4009 
  4010     inductive_set
  4011       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4012       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4013       for z_1 :: U_1 and ... and z_n :: U_m
  4014     where
  4015       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4016     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4017     | ...
  4018 
  4019   if the additional syntax "p ..." is required.
  4020 
  4021   Numerous examples can be found in the subdirectories src/HOL/Auth,
  4022   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  4023 
  4024   INCOMPATIBILITIES:
  4025 
  4026   - Since declaration and definition of inductive sets or predicates
  4027     is no longer separated, abbreviations involving the newly
  4028     introduced sets or predicates must be specified together with the
  4029     introduction rules after the 'where' keyword (see above), rather
  4030     than before the actual inductive definition.
  4031 
  4032   - The variables in induction and elimination rules are now
  4033     quantified in the order of their occurrence in the introduction
  4034     rules, rather than in alphabetical order. Since this may break
  4035     some proofs, these proofs either have to be repaired, e.g. by
  4036     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  4037     statements of the form
  4038 
  4039       case (rule_i a_i_1 ... a_i_{k_i})
  4040 
  4041     or the old order of quantification has to be restored by explicitly adding
  4042     meta-level quantifiers in the introduction rules, i.e.
  4043 
  4044       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  4045 
  4046   - The format of the elimination rules is now
  4047 
  4048       p z_1 ... z_m x_1 ... x_n ==>
  4049         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4050         ==> ... ==> P
  4051 
  4052     for predicates and
  4053 
  4054       (x_1, ..., x_n) : s z_1 ... z_m ==>
  4055         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4056         ==> ... ==> P
  4057 
  4058     for sets rather than
  4059 
  4060       x : s z_1 ... z_m ==>
  4061         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  4062         ==> ... ==> P
  4063 
  4064     This may require terms in goals to be expanded to n-tuples
  4065     (e.g. using case_tac or simplification with the split_paired_all
  4066     rule) before the above elimination rule is applicable.
  4067 
  4068   - The elimination or case analysis rules for (mutually) inductive
  4069     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  4070     list of rules "p_1_..._p_k.elims" is no longer available.
  4071 
  4072 * New package "function"/"fun" for general recursive functions,
  4073 supporting mutual and nested recursion, definitions in local contexts,
  4074 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  4075 for small examples, and the separate tutorial on the function
  4076 package. The old recdef "package" is still available as before, but
  4077 users are encouraged to use the new package.
  4078 
  4079 * Method "lexicographic_order" automatically synthesizes termination
  4080 relations as lexicographic combinations of size measures. 
  4081 
  4082 * Case-expressions allow arbitrary constructor-patterns (including
  4083 "_") and take their order into account, like in functional
  4084 programming.  Internally, this is translated into nested
  4085 case-expressions; missing cases are added and mapped to the predefined
  4086 constant "undefined". In complicated cases printing may no longer show
  4087 the original input but the internal form. Lambda-abstractions allow
  4088 the same form of pattern matching: "% pat1 => e1 | ..." is an
  4089 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  4090 variable.
  4091 
  4092 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  4093 is an abbreviation for "of_nat :: nat => int". The simplification
  4094 rules for "of_nat" have been changed to work like "int" did
  4095 previously.  Potential INCOMPATIBILITY:
  4096   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  4097   - of_nat_diff and of_nat_mult are no longer default simp rules
  4098 
  4099 * Method "algebra" solves polynomial equations over (semi)rings using
  4100 Groebner bases. The (semi)ring structure is defined by locales and the
  4101 tool setup depends on that generic context. Installing the method for
  4102 a specific type involves instantiating the locale and possibly adding
  4103 declarations for computation on the coefficients.  The method is
  4104 already instantiated for natural numbers and for the axiomatic class
  4105 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  4106 CALCULEMUS 2007 for the general principles underlying this
  4107 architecture of context-aware proof-tools.
  4108 
  4109 * Method "ferrack" implements quantifier elimination over
  4110 special-purpose dense linear orders using locales (analogous to
  4111 "algebra"). The method is already installed for class
  4112 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  4113 rat, etc.
  4114 
  4115 * Former constant "List.op @" now named "List.append".  Use ML
  4116 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  4117 circumvent possible incompatibilities when working on ML level.
  4118 
  4119 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  4120 
  4121 * New function listsum :: 'a list => 'a for arbitrary monoids.
  4122 Special syntax: "SUM x <- xs. f x" (and latex variants)
  4123 
  4124 * New syntax for Haskell-like list comprehension (input only), eg.
  4125 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  4126 
  4127 * The special syntax for function "filter" has changed from [x :
  4128 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  4129 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  4130 
  4131 * [a..b] is now defined for arbitrary linear orders.  It used to be
  4132 defined on nat only, as an abbreviation for [a..<Suc b]
  4133 INCOMPATIBILITY.
  4134 
  4135 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  4136 
  4137 * New functions "sorted" and "sort" in src/HOL/List.thy.
  4138 
  4139 * New lemma collection field_simps (an extension of ring_simps) for
  4140 manipulating (in)equations involving division. Multiplies with all
  4141 denominators that can be proved to be non-zero (in equations) or
  4142 positive/negative (in inequations).
  4143 
  4144 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  4145 have been improved and renamed to ring_simps, group_simps and
  4146 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  4147 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  4148 
  4149 * Theory Library/Commutative_Ring: switched from recdef to function
  4150 package; constants add, mul, pow now curried.  Infix syntax for
  4151 algebraic operations.
  4152 
  4153 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  4154 INCOMPATIBILITY.
  4155 
  4156 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  4157 INCOMPATIBILITY.
  4158 
  4159 * HOL/records: generalised field-update to take a function on the
  4160 field rather than the new value: r(|A := x|) is translated to A_update
  4161 (K x) r The K-combinator that is internally used is called K_record.
  4162 INCOMPATIBILITY: Usage of the plain update functions has to be
  4163 adapted.
  4164  
  4165 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  4166 * x = 0, which are required for a semiring.  Richer structures do not
  4167 inherit from semiring_0 anymore, because this property is a theorem
  4168 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  4169 there is more to prove, but this is mostly trivial.
  4170 
  4171 * Class "recpower" is generalized to arbitrary monoids, not just
  4172 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  4173 commutativity or semiring properties additionally.
  4174 
  4175 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  4176 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  4177 better use 'abbreviation'.
  4178 
  4179 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  4180 
  4181 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  4182 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  4183 significant changes for setting up numeral syntax for types:
  4184   - New constants Numeral.pred and Numeral.succ instead
  4185       of former Numeral.bin_pred and Numeral.bin_succ.
  4186   - Use integer operations instead of bin_add, bin_mult and so on.
  4187   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  4188   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  4189 
  4190 See src/HOL/Integ/IntArith.thy for an example setup.
  4191 
  4192 * Command 'normal_form' computes the normal form of a term that may
  4193 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  4194 produces ``[b, c, a]'' (without proof).  This command is suitable for
  4195 heavy-duty computations because the functions are compiled to ML
  4196 first.  Correspondingly, a method "normalization" is provided.  See
  4197 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  4198 
  4199 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  4200 25 like -->); output depends on the "iff" print_mode, the default is
  4201 "A = B" (with priority 50).
  4202 
  4203 * Relations less (<) and less_eq (<=) are also available on type bool.
  4204 Modified syntax to disallow nesting without explicit parentheses,
  4205 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  4206 INCOMPATIBILITY.
  4207 
  4208 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  4209 
  4210 * Relation composition operator "op O" now has precedence 75 and binds
  4211 stronger than union and intersection. INCOMPATIBILITY.
  4212 
  4213 * The old set interval syntax "{m..n(}" (and relatives) has been
  4214 removed.  Use "{m..<n}" (and relatives) instead.
  4215 
  4216 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  4217 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  4218 ``declare [[simproc del: neq]]''.
  4219 
  4220 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  4221 True/False.
  4222 
  4223 * Theorem Cons_eq_map_conv no longer declared as "simp".
  4224 
  4225 * Theorem setsum_mult renamed to setsum_right_distrib.
  4226 
  4227 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  4228 ``rule'' method.
  4229 
  4230 * Reimplemented methods "sat" and "satx", with several improvements:
  4231 goals no longer need to be stated as "<prems> ==> False", equivalences
  4232 (i.e. "=" on type bool) are handled, variable names of the form
  4233 "lit_<n>" are no longer reserved, significant speedup.
  4234 
  4235 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  4236 zChaff is still supported as well.
  4237 
  4238 * 'inductive' and 'datatype': provide projections of mutual rules,
  4239 bundled as foo_bar.inducts;
  4240 
  4241 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  4242 Library.
  4243 
  4244 * Library: moved theory Accessible_Part to main HOL.
  4245 
  4246 * Library: added theory Coinductive_List of potentially infinite lists
  4247 as greatest fixed-point.
  4248 
  4249 * Library: added theory AssocList which implements (finite) maps as
  4250 association lists.
  4251 
  4252 * Method "evaluation" solves goals (i.e. a boolean expression)
  4253 efficiently by compiling it to ML.  The goal is "proved" (via an
  4254 oracle) if it evaluates to True.
  4255 
  4256 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  4257 also when invoked by the simplifier.  This results in the Simplifier
  4258 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  4259 Configuration option fast_arith_split_limit=0 recovers the old
  4260 behavior.
  4261 
  4262 * Support for hex (0x20) and binary (0b1001) numerals.
  4263 
  4264 * New method: reify eqs (t), where eqs are equations for an
  4265 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  4266 parameter, computes a term s::'b and a list xs::'a list and proves the
  4267 theorem I xs s = t. This is also known as reification or quoting. The
  4268 resulting theorem is applied to the subgoal to substitute t with I xs
  4269 s.  If t is omitted, the subgoal itself is reified.
  4270 
  4271 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  4272 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  4273 where f is supposed to be a computable function (in the sense of code
  4274 generattion). The method uses reify to compute s and xs as above then
  4275 applies corr_thm and uses normalization by evaluation to "prove" f s =
  4276 r and finally gets the theorem t = r, which is again applied to the
  4277 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  4278 
  4279 * Reflection: Automatic reification now handels binding, an example is
  4280 available in src/HOL/ex/ReflectionEx.thy
  4281 
  4282 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  4283 command 'statespace' that is similar to 'record', but introduces an
  4284 abstract specification based on the locale infrastructure instead of
  4285 HOL types.  This leads to extra flexibility in composing state spaces,
  4286 in particular multiple inheritance and renaming of components.
  4287 
  4288 
  4289 *** HOL-Complex ***
  4290 
  4291 * Hyperreal: Functions root and sqrt are now defined on negative real
  4292 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  4293 Nonnegativity side conditions have been removed from many lemmas, so
  4294 that more subgoals may now be solved by simplification; potential
  4295 INCOMPATIBILITY.
  4296 
  4297 * Real: new type classes formalize real normed vector spaces and
  4298 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  4299 and norm :: 'a => real.
  4300 
  4301 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  4302 reals into other types. The overloaded constant Reals :: 'a set is now
  4303 defined as range of_real; potential INCOMPATIBILITY.
  4304 
  4305 * Real: proper support for ML code generation, including 'quickcheck'.
  4306 Reals are implemented as arbitrary precision rationals.
  4307 
  4308 * Hyperreal: Several constants that previously worked only for the
  4309 reals have been generalized, so they now work over arbitrary vector
  4310 spaces. Type annotations may need to be added in some cases; potential
  4311 INCOMPATIBILITY.
  4312 
  4313   Infinitesimal  :: ('a::real_normed_vector) star set
  4314   HFinite        :: ('a::real_normed_vector) star set
  4315   HInfinite      :: ('a::real_normed_vector) star set
  4316   approx         :: ('a::real_normed_vector) star => 'a star => bool
  4317   monad          :: ('a::real_normed_vector) star => 'a star set
  4318   galaxy         :: ('a::real_normed_vector) star => 'a star set
  4319   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  4320   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  4321   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  4322   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  4323   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  4324   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  4325   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  4326   sgn            :: 'a::real_normed_vector => 'a
  4327   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  4328 
  4329 * Complex: Some complex-specific constants are now abbreviations for
  4330 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  4331 hnorm.  Other constants have been entirely removed in favor of the
  4332 polymorphic versions (INCOMPATIBILITY):
  4333 
  4334   approx        <-- capprox
  4335   HFinite       <-- CFinite
  4336   HInfinite     <-- CInfinite
  4337   Infinitesimal <-- CInfinitesimal
  4338   monad         <-- cmonad
  4339   galaxy        <-- cgalaxy
  4340   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  4341   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  4342   (ns)deriv     <-- (ns)cderiv
  4343 
  4344 
  4345 *** HOL-Algebra ***
  4346 
  4347 * Formalisation of ideals and the quotient construction over rings.
  4348 
  4349 * Order and lattice theory no longer based on records.
  4350 INCOMPATIBILITY.
  4351 
  4352 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  4353 greatest_closed.  INCOMPATIBILITY.
  4354 
  4355 * Method algebra is now set up via an attribute.  For examples see
  4356 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  4357 of algebraic structures.
  4358 
  4359 * Renamed theory CRing to Ring.
  4360 
  4361 
  4362 *** HOL-Nominal ***
  4363 
  4364 * Substantial, yet incomplete support for nominal datatypes (binding
  4365 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  4366 src/HOL/Nominal/Examples.  Prospective users should consult
  4367 http://isabelle.in.tum.de/nominal/
  4368 
  4369 
  4370 *** ML ***
  4371 
  4372 * ML basics: just one true type int, which coincides with IntInf.int
  4373 (even on SML/NJ).
  4374 
  4375 * ML within Isar: antiquotations allow to embed statically-checked
  4376 formal entities in the source, referring to the context available at
  4377 compile-time.  For example:
  4378 
  4379 ML {* @{sort "{zero,one}"} *}
  4380 ML {* @{typ "'a => 'b"} *}
  4381 ML {* @{term "%x. x"} *}
  4382 ML {* @{prop "x == y"} *}
  4383 ML {* @{ctyp "'a => 'b"} *}
  4384 ML {* @{cterm "%x. x"} *}
  4385 ML {* @{cprop "x == y"} *}
  4386 ML {* @{thm asm_rl} *}
  4387 ML {* @{thms asm_rl} *}
  4388 ML {* @{type_name c} *}
  4389 ML {* @{type_syntax c} *}
  4390 ML {* @{const_name c} *}
  4391 ML {* @{const_syntax c} *}
  4392 ML {* @{context} *}
  4393 ML {* @{theory} *}
  4394 ML {* @{theory Pure} *}
  4395 ML {* @{theory_ref} *}
  4396 ML {* @{theory_ref Pure} *}
  4397 ML {* @{simpset} *}
  4398 ML {* @{claset} *}
  4399 ML {* @{clasimpset} *}
  4400 
  4401 The same works for sources being ``used'' within an Isar context.
  4402 
  4403 * ML in Isar: improved error reporting; extra verbosity with
  4404 ML_Context.trace enabled.
  4405 
  4406 * Pure/General/table.ML: the join operations now works via exceptions
  4407 DUP/SAME instead of type option. This is simpler in simple cases, and
  4408 admits slightly more efficient complex applications.
  4409 
  4410 * Pure: 'advanced' translation functions (parse_translation etc.) now
  4411 use Context.generic instead of just theory.
  4412 
  4413 * Pure: datatype Context.generic joins theory/Proof.context and
  4414 provides some facilities for code that works in either kind of
  4415 context, notably GenericDataFun for uniform theory and proof data.
  4416 
  4417 * Pure: simplified internal attribute type, which is now always
  4418 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  4419 local (Proof.context) attributes have been discontinued, while
  4420 minimizing code duplication. Thm.rule_attribute and
  4421 Thm.declaration_attribute build canonical attributes; see also structure
  4422 Context for further operations on Context.generic, notably
  4423 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  4424 declarations and definitions.
  4425 
  4426 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  4427 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  4428 init only required for impure data. INCOMPATIBILITY: empty really need
  4429 to be empty (no dependencies on theory content!)
  4430 
  4431 * Pure/kernel: consts certification ignores sort constraints given in
  4432 signature declarations. (This information is not relevant to the
  4433 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  4434 potential INCOMPATIBILITY.
  4435 
  4436 * Pure: axiomatic type classes are now purely definitional, with
  4437 explicit proofs of class axioms and super class relations performed
  4438 internally. See Pure/axclass.ML for the main internal interfaces --
  4439 notably AxClass.define_class supercedes AxClass.add_axclass, and
  4440 AxClass.axiomatize_class/classrel/arity supersede
  4441 Sign.add_classes/classrel/arities.
  4442 
  4443 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  4444 global/local versions on theory vs. Proof.context have been
  4445 discontinued; Attrib.syntax and Method.syntax have been adapted
  4446 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  4447 attributes, methods, etc.
  4448 
  4449 * Pure: several functions of signature "... -> theory -> theory * ..."
  4450 have been reoriented to "... -> theory -> ... * theory" in order to
  4451 allow natural usage in combination with the ||>, ||>>, |-> and
  4452 fold_map combinators.
  4453 
  4454 * Pure: official theorem names (closed derivations) and additional
  4455 comments (tags) are now strictly separate.  Name hints -- which are
  4456 maintained as tags -- may be attached any time without affecting the
  4457 derivation.
  4458 
  4459 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  4460 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  4461 achieve the old behaviour.
  4462 
  4463 * Pure: the "Goal" constant is now called "prop", supporting a
  4464 slightly more general idea of ``protecting'' meta-level rule
  4465 statements.
  4466 
  4467 * Pure: Logic.(un)varify only works in a global context, which is now
  4468 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  4469 Logic.legacy_(un)varify as temporary workaround.
  4470 
  4471 * Pure: structure Name provides scalable operations for generating
  4472 internal variable names, notably Name.variants etc.  This replaces
  4473 some popular functions from term.ML:
  4474 
  4475   Term.variant		->  Name.variant
  4476   Term.variantlist	->  Name.variant_list
  4477   Term.invent_names	->  Name.invent_list
  4478 
  4479 Note that low-level renaming rarely occurs in new code -- operations
  4480 from structure Variable are used instead (see below).
  4481 
  4482 * Pure: structure Variable provides fundamental operations for proper
  4483 treatment of fixed/schematic variables in a context.  For example,
  4484 Variable.import introduces fixes for schematics of given facts and
  4485 Variable.export reverses the effect (up to renaming) -- this replaces
  4486 various freeze_thaw operations.
  4487 
  4488 * Pure: structure Goal provides simple interfaces for
  4489 init/conclude/finish and tactical prove operations (replacing former
  4490 Tactic.prove).  Goal.prove is the canonical way to prove results
  4491 within a given context; Goal.prove_global is a degraded version for
  4492 theory level goals, including a global Drule.standard.  Note that
  4493 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  4494 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  4495 in a locale context).
  4496 
  4497 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  4498 and type checking (Syntax.check_term etc.), with common combinations
  4499 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  4500 which are considered legacy and await removal.
  4501 
  4502 * Pure/Syntax: generic interfaces for type unchecking
  4503 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  4504 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  4505 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  4506 available for convenience, but refer to the very same operations using
  4507 a mere theory instead of a full context.
  4508 
  4509 * Isar: simplified treatment of user-level errors, using exception
  4510 ERROR of string uniformly.  Function error now merely raises ERROR,
  4511 without any side effect on output channels.  The Isar toplevel takes
  4512 care of proper display of ERROR exceptions.  ML code may use plain
  4513 handle/can/try; cat_error may be used to concatenate errors like this:
  4514 
  4515   ... handle ERROR msg => cat_error msg "..."
  4516 
  4517 Toplevel ML code (run directly or through the Isar toplevel) may be
  4518 embedded into the Isar toplevel with exception display/debug like
  4519 this:
  4520 
  4521   Isar.toplevel (fn () => ...)
  4522 
  4523 INCOMPATIBILITY, removed special transform_error facilities, removed
  4524 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  4525 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  4526 -- use plain ERROR instead.
  4527 
  4528 * Isar: theory setup now has type (theory -> theory), instead of a
  4529 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  4530 
  4531 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  4532 ProofContext.debug/verbose flags.
  4533 
  4534 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  4535 theory before entering a proof state.  Transactions now always see a
  4536 quasi-functional intermediate checkpoint, both in interactive and
  4537 batch mode.
  4538 
  4539 * Isar: simplified interfaces for outer syntax.  Renamed
  4540 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  4541 OuterSyntax.add_parsers -- this functionality is now included in
  4542 OuterSyntax.command etc.  INCOMPATIBILITY.
  4543 
  4544 * Simplifier: the simpset of a running simplification process now
  4545 contains a proof context (cf. Simplifier.the_context), which is the
  4546 very context that the initial simpset has been retrieved from (by
  4547 simpset_of/local_simpset_of).  Consequently, all plug-in components
  4548 (solver, looper etc.) may depend on arbitrary proof data.
  4549 
  4550 * Simplifier.inherit_context inherits the proof context (plus the
  4551 local bounds) of the current simplification process; any simproc
  4552 etc. that calls the Simplifier recursively should do this!  Removed
  4553 former Simplifier.inherit_bounds, which is already included here --
  4554 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  4555 specify an explicit context using Simplifier.context/theory_context.
  4556 
  4557 * Simplifier/Classical Reasoner: more abstract interfaces
  4558 change_simpset/claset for modifying the simpset/claset reference of a
  4559 theory; raw versions simpset/claset_ref etc. have been discontinued --
  4560 INCOMPATIBILITY.
  4561 
  4562 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  4563 "Trueprop" etc.
  4564 
  4565 
  4566 *** System ***
  4567 
  4568 * settings: the default heap location within ISABELLE_HOME_USER now
  4569 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  4570 Isabelle installations.
  4571 
  4572 * isabelle-process: option -S (secure mode) disables some critical
  4573 operations, notably runtime compilation and evaluation of ML source
  4574 code.
  4575 
  4576 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  4577 
  4578 * Support for parallel execution, using native multicore support of
  4579 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  4580 independent theories, according to the given theory header
  4581 specifications. The maximum number of worker threads is specified via
  4582 usedir option -M or the "max-threads" setting in Proof General. A
  4583 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  4584 to 6 on a 8-core machine.  User-code needs to observe certain
  4585 guidelines for thread-safe programming, see appendix A in the Isar
  4586 Implementation manual.
  4587 
  4588 
  4589 
  4590 New in Isabelle2005 (October 2005)
  4591 ----------------------------------
  4592 
  4593 *** General ***
  4594 
  4595 * Theory headers: the new header syntax for Isar theories is
  4596 
  4597   theory <name>
  4598   imports <theory1> ... <theoryN>
  4599   uses <file1> ... <fileM>
  4600   begin
  4601 
  4602 where the 'uses' part is optional.  The previous syntax
  4603 
  4604   theory <name> = <theory1> + ... + <theoryN>:
  4605 
  4606 will disappear in the next release.  Use isatool fixheaders to convert
  4607 existing theory files.  Note that there is no change in ancient
  4608 non-Isar theories now, but these will disappear soon.
  4609 
  4610 * Theory loader: parent theories can now also be referred to via
  4611 relative and absolute paths.
  4612 
  4613 * Command 'find_theorems' searches for a list of criteria instead of a
  4614 list of constants. Known criteria are: intro, elim, dest, name:string,
  4615 simp:term, and any term. Criteria can be preceded by '-' to select
  4616 theorems that do not match. Intro, elim, dest select theorems that
  4617 match the current goal, name:s selects theorems whose fully qualified
  4618 name contain s, and simp:term selects all simplification rules whose
  4619 lhs match term.  Any other term is interpreted as pattern and selects
  4620 all theorems matching the pattern. Available in ProofGeneral under
  4621 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  4622 
  4623   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  4624 
  4625 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  4626 matching the current goal as introduction rule and not having "HOL."
  4627 in their name (i.e. not being defined in theory HOL).
  4628 
  4629 * Command 'thms_containing' has been discontinued in favour of
  4630 'find_theorems'; INCOMPATIBILITY.
  4631 
  4632 * Communication with Proof General is now 8bit clean, which means that
  4633 Unicode text in UTF-8 encoding may be used within theory texts (both
  4634 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4635 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4636 
  4637   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4638   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4639 
  4640 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4641 Classical Reasoner.  Typical big applications run around 2 times
  4642 faster.
  4643 
  4644 
  4645 *** Document preparation ***
  4646 
  4647 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4648 of raw sources.  Only those symbols that do not require additional
  4649 LaTeX packages (depending on comments in isabellesym.sty) are
  4650 displayed properly, everything else is left verbatim.  isatool display
  4651 and isatool print are used as front ends (these are subject to the
  4652 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4653 
  4654 * Command tags control specific markup of certain regions of text,
  4655 notably folding and hiding.  Predefined tags include "theory" (for
  4656 theory begin and end), "proof" for proof commands, and "ML" for
  4657 commands involving ML code; the additional tags "visible" and
  4658 "invisible" are unused by default.  Users may give explicit tag
  4659 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4660 interpretation of tags is determined by the LaTeX job during document
  4661 preparation: see option -V of isatool usedir, or options -n and -t of
  4662 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4663 \isadroptag.
  4664 
  4665 Several document versions may be produced at the same time via isatool
  4666 usedir (the generated index.html will link all of them).  Typical
  4667 specifications include ''-V document=theory,proof,ML'' to present
  4668 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4669 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4670 these parts without any formal replacement text.  The Isabelle site
  4671 default settings produce ''document'' and ''outline'' versions as
  4672 specified above.
  4673 
  4674 * Several new antiquotations:
  4675 
  4676   @{term_type term} prints a term with its type annotated;
  4677 
  4678   @{typeof term} prints the type of a term;
  4679 
  4680   @{const const} is the same as @{term const}, but checks that the
  4681   argument is a known logical constant;
  4682 
  4683   @{term_style style term} and @{thm_style style thm} print a term or
  4684   theorem applying a "style" to it
  4685 
  4686   @{ML text}
  4687 
  4688 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4689 definitions, equations, inequations etc., 'concl' printing only the
  4690 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4691 to print the specified premise.  TermStyle.add_style provides an ML
  4692 interface for introducing further styles.  See also the "LaTeX Sugar"
  4693 document practical applications.  The ML antiquotation prints
  4694 type-checked ML expressions verbatim.
  4695 
  4696 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4697 and 'text' support optional locale specification '(in loc)', which
  4698 specifies the default context for interpreting antiquotations.  For
  4699 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4700 
  4701 * Option 'locale=NAME' of antiquotations specifies an alternative
  4702 context interpreting the subsequent argument.  For example: @{thm
  4703 [locale=lattice] inf_assoc}.
  4704 
  4705 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4706 a proof context.
  4707 
  4708 * Proper output of antiquotations for theory commands involving a
  4709 proof context (such as 'locale' or 'theorem (in loc) ...').
  4710 
  4711 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4712 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4713 
  4714 * isatool usedir: new option -C (default true) controls whether option
  4715 -D should include a copy of the original document directory; -C false
  4716 prevents unwanted effects such as copying of administrative CVS data.
  4717 
  4718 
  4719 *** Pure ***
  4720 
  4721 * Considerably improved version of 'constdefs' command.  Now performs
  4722 automatic type-inference of declared constants; additional support for
  4723 local structure declarations (cf. locales and HOL records), see also
  4724 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4725 sequential dependencies of definitions within a single 'constdefs'
  4726 section; moreover, the declared name needs to be an identifier.  If
  4727 all fails, consider to fall back on 'consts' and 'defs' separately.
  4728 
  4729 * Improved indexed syntax and implicit structures.  First of all,
  4730 indexed syntax provides a notational device for subscripted
  4731 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4732 expressions.  Secondly, in a local context with structure
  4733 declarations, number indexes \<^sub>n or the empty index (default
  4734 number 1) refer to a certain fixed variable implicitly; option
  4735 show_structs controls printing of implicit structures.  Typical
  4736 applications of these concepts involve record types and locales.
  4737 
  4738 * New command 'no_syntax' removes grammar declarations (and
  4739 translations) resulting from the given syntax specification, which is
  4740 interpreted in the same manner as for the 'syntax' command.
  4741 
  4742 * 'Advanced' translation functions (parse_translation etc.) may depend
  4743 on the signature of the theory context being presently used for
  4744 parsing/printing, see also isar-ref manual.
  4745 
  4746 * Improved 'oracle' command provides a type-safe interface to turn an
  4747 ML expression of type theory -> T -> term into a primitive rule of
  4748 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4749 is already included here); see also FOL/ex/IffExample.thy;
  4750 INCOMPATIBILITY.
  4751 
  4752 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4753 before); "cI" is no longer bound, use "c.intro" instead.
  4754 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4755 axclasses vs. locales.
  4756 
  4757 * Improved internal renaming of symbolic identifiers -- attach primes
  4758 instead of base 26 numbers.
  4759 
  4760 * New flag show_question_marks controls printing of leading question
  4761 marks in schematic variable names.
  4762 
  4763 * In schematic variable names, *any* symbol following \<^isub> or
  4764 \<^isup> is now treated as part of the base name.  For example, the
  4765 following works without printing of awkward ".0" indexes:
  4766 
  4767   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4768     by simp
  4769 
  4770 * Inner syntax includes (*(*nested*) comments*).
  4771 
  4772 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4773 annotations as "(00...)".
  4774 
  4775 * Clear separation of logical types and nonterminals, where the latter
  4776 may only occur in 'syntax' specifications or type abbreviations.
  4777 Before that distinction was only partially implemented via type class
  4778 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4779 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4780 exotic syntax specifications may require further adaption
  4781 (e.g. Cube/Cube.thy).
  4782 
  4783 * Removed obsolete type class "logic", use the top sort {} instead.
  4784 Note that non-logical types should be declared as 'nonterminals'
  4785 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4786 specifications.
  4787 
  4788 * Attributes 'induct' and 'cases': type or set names may now be
  4789 locally fixed variables as well.
  4790 
  4791 * Simplifier: can now control the depth to which conditional rewriting
  4792 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4793 Limit.
  4794 
  4795 * Simplifier: simplification procedures may now take the current
  4796 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4797 interface), which is very useful for calling the Simplifier
  4798 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4799 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4800 low-level mk_simproc no longer applies Logic.varify internally, to
  4801 allow for use in a context of fixed variables.
  4802 
  4803 * thin_tac now works even if the assumption being deleted contains !!
  4804 or ==>.  More generally, erule now works even if the major premise of
  4805 the elimination rule contains !! or ==>.
  4806 
  4807 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4808 
  4809 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4810 from Pure, which contains all common declarations already.  Both
  4811 theories are defined via plain Isabelle/Isar .thy files.
  4812 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4813 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4814 use isatool fixcpure to adapt your theory and ML sources.
  4815 
  4816 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4817 selections of theorems in named facts via index ranges.
  4818 
  4819 * 'print_theorems': in theory mode, really print the difference
  4820 wrt. the last state (works for interactive theory development only),
  4821 in proof mode print all local facts (cf. 'print_facts');
  4822 
  4823 * 'hide': option '(open)' hides only base names.
  4824 
  4825 * More efficient treatment of intermediate checkpoints in interactive
  4826 theory development.
  4827 
  4828 * Code generator is now invoked via code_module (incremental code
  4829 generation) and code_library (modular code generation, ML structures
  4830 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4831 must be quoted when used as identifiers.
  4832 
  4833 * New 'value' command for reading, evaluating and printing terms using
  4834 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4835 quoted when used as identifier.
  4836 
  4837 
  4838 *** Locales ***
  4839 
  4840 * New commands for the interpretation of locale expressions in
  4841 theories (1), locales (2) and proof contexts (3).  These generate
  4842 proof obligations from the expression specification.  After the
  4843 obligations have been discharged, theorems of the expression are added
  4844 to the theory, target locale or proof context.  The synopsis of the
  4845 commands is a follows:
  4846 
  4847   (1) interpretation expr inst
  4848   (2) interpretation target < expr
  4849   (3) interpret expr inst
  4850 
  4851 Interpretation in theories and proof contexts require a parameter
  4852 instantiation of terms from the current context.  This is applied to
  4853 specifications and theorems of the interpreted expression.
  4854 Interpretation in locales only permits parameter renaming through the
  4855 locale expression.  Interpretation is smart in that interpretations
  4856 that are active already do not occur in proof obligations, neither are
  4857 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4858 inspect active interpretations of a particular locale.  For details,
  4859 see the Isar Reference manual.  Examples can be found in
  4860 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4861 
  4862 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4863 'interpret' instead.
  4864 
  4865 * New context element 'constrains' for adding type constraints to
  4866 parameters.
  4867 
  4868 * Context expressions: renaming of parameters with syntax
  4869 redeclaration.
  4870 
  4871 * Locale declaration: 'includes' disallowed.
  4872 
  4873 * Proper static binding of attribute syntax -- i.e. types / terms /
  4874 facts mentioned as arguments are always those of the locale definition
  4875 context, independently of the context of later invocations.  Moreover,
  4876 locale operations (renaming and type / term instantiation) are applied
  4877 to attribute arguments as expected.
  4878 
  4879 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4880 actual attributes; rare situations may require Attrib.attribute to
  4881 embed those attributes into Attrib.src that lack concrete syntax.
  4882 Attribute implementations need to cooperate properly with the static
  4883 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4884 Attrib.XXX_thm etc. already do the right thing without further
  4885 intervention.  Only unusual applications -- such as "where" or "of"
  4886 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4887 on the context and the facts involved -- may have to assign parsed
  4888 values to argument tokens explicitly.
  4889 
  4890 * Changed parameter management in theorem generation for long goal
  4891 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4892 theorem statement in rare situations.
  4893 
  4894 * Locale inspection command 'print_locale' omits notes elements.  Use
  4895 'print_locale!' to have them included in the output.
  4896 
  4897 
  4898 *** Provers ***
  4899 
  4900 * Provers/hypsubst.ML: improved version of the subst method, for
  4901 single-step rewriting: it now works in bound variable contexts. New is
  4902 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  4903 rewrite a different subterm than the original subst method, which is
  4904 still available as 'simplesubst'.
  4905 
  4906 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  4907 and quasi orders.
  4908 
  4909 * Provers/trancl.ML: new transitivity reasoner for transitive and
  4910 reflexive-transitive closure of relations.
  4911 
  4912 * Provers/blast.ML: new reference depth_limit to make blast's depth
  4913 limit (previously hard-coded with a value of 20) user-definable.
  4914 
  4915 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  4916 is peformed already.  Object-logics merely need to finish their
  4917 initial simpset configuration as before.  INCOMPATIBILITY.
  4918 
  4919 
  4920 *** HOL ***
  4921 
  4922 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  4923 
  4924   syntax (epsilon)
  4925     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  4926 
  4927 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  4928 and x-symbol; use option '-m epsilon' to get it actually printed.
  4929 Moreover, the mathematically important symbolic identifier \<epsilon>
  4930 becomes available as variable, constant etc.  INCOMPATIBILITY,
  4931 
  4932 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  4933 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  4934 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  4935 support corresponding Isar calculations.
  4936 
  4937 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  4938 instead of ":".
  4939 
  4940 * theory SetInterval: changed the syntax for open intervals:
  4941 
  4942   Old       New
  4943   {..n(}    {..<n}
  4944   {)n..}    {n<..}
  4945   {m..n(}   {m..<n}
  4946   {)m..n}   {m<..n}
  4947   {)m..n(}  {m<..<n}
  4948 
  4949 The old syntax is still supported but will disappear in the next
  4950 release.  For conversion use the following Emacs search and replace
  4951 patterns (these are not perfect but work quite well):
  4952 
  4953   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  4954   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  4955 
  4956 * Theory Commutative_Ring (in Library): method comm_ring for proving
  4957 equalities in commutative rings; method 'algebra' provides a generic
  4958 interface.
  4959 
  4960 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  4961 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  4962 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  4963 be a tuple pattern.
  4964 
  4965 Some new syntax forms are available:
  4966 
  4967   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  4968   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  4969   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  4970   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  4971 
  4972 The latter form "\<Sum>x < k. e" used to be based on a separate
  4973 function "Summation", which has been discontinued.
  4974 
  4975 * theory Finite_Set: in structured induction proofs, the insert case
  4976 is now 'case (insert x F)' instead of the old counterintuitive 'case
  4977 (insert F x)'.
  4978 
  4979 * The 'refute' command has been extended to support a much larger
  4980 fragment of HOL, including axiomatic type classes, constdefs and
  4981 typedefs, inductive datatypes and recursion.
  4982 
  4983 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  4984 Requires zChaff with proof generation to be installed.  See
  4985 HOL/ex/SAT_Examples.thy for examples.
  4986 
  4987 * Datatype induction via method 'induct' now preserves the name of the
  4988 induction variable. For example, when proving P(xs::'a list) by
  4989 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  4990 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  4991 in unstructured proof scripts.
  4992 
  4993 * Reworked implementation of records.  Improved scalability for
  4994 records with many fields, avoiding performance problems for type
  4995 inference. Records are no longer composed of nested field types, but
  4996 of nested extension types. Therefore the record type only grows linear
  4997 in the number of extensions and not in the number of fields.  The
  4998 top-level (users) view on records is preserved.  Potential
  4999 INCOMPATIBILITY only in strange cases, where the theory depends on the
  5000 old record representation. The type generated for a record is called
  5001 <record_name>_ext_type.
  5002 
  5003 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  5004 proofs triggered by a record definition or a simproc (if
  5005 quick_and_dirty is enabled).  Definitions of large records can take
  5006 quite long.
  5007 
  5008 New simproc record_upd_simproc for simplification of multiple record
  5009 updates enabled by default.  Moreover, trivial updates are also
  5010 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  5011 occasionally, since simplification is more powerful by default.
  5012 
  5013 * typedef: proper support for polymorphic sets, which contain extra
  5014 type-variables in the term.
  5015 
  5016 * Simplifier: automatically reasons about transitivity chains
  5017 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  5018 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  5019 old proofs break occasionally as simplification may now solve more
  5020 goals than previously.
  5021 
  5022 * Simplifier: converts x <= y into x = y if assumption y <= x is
  5023 present.  Works for all partial orders (class "order"), in particular
  5024 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  5025 just like y <= x.
  5026 
  5027 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  5028 bound variable or a constant then the let is unfolded.  Otherwise
  5029 first a is simplified to b, and then f b is simplified to g. If
  5030 possible we abstract b from g arriving at "let x = b in h x",
  5031 otherwise we unfold the let and arrive at g.  The simproc can be
  5032 enabled/disabled by the reference use_let_simproc.  Potential
  5033 INCOMPATIBILITY since simplification is more powerful by default.
  5034 
  5035 * Classical reasoning: the meson method now accepts theorems as arguments.
  5036 
  5037 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  5038 jobs to provide advice on the provability of subgoals.
  5039 
  5040 * Theory OrderedGroup and Ring_and_Field: various additions and
  5041 improvements to faciliate calculations involving equalities and
  5042 inequalities.
  5043 
  5044 The following theorems have been eliminated or modified
  5045 (INCOMPATIBILITY):
  5046 
  5047   abs_eq             now named abs_of_nonneg
  5048   abs_of_ge_0        now named abs_of_nonneg
  5049   abs_minus_eq       now named abs_of_nonpos
  5050   imp_abs_id         now named abs_of_nonneg
  5051   imp_abs_neg_id     now named abs_of_nonpos
  5052   mult_pos           now named mult_pos_pos
  5053   mult_pos_le        now named mult_nonneg_nonneg
  5054   mult_pos_neg_le    now named mult_nonneg_nonpos
  5055   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  5056   mult_neg           now named mult_neg_neg
  5057   mult_neg_le        now named mult_nonpos_nonpos
  5058 
  5059 * The following lemmas in Ring_and_Field have been added to the simplifier:
  5060      
  5061      zero_le_square
  5062      not_square_less_zero 
  5063 
  5064   The following lemmas have been deleted from Real/RealPow:
  5065   
  5066      realpow_zero_zero
  5067      realpow_two
  5068      realpow_less
  5069      zero_le_power
  5070      realpow_two_le
  5071      abs_realpow_two
  5072      realpow_two_abs     
  5073 
  5074 * Theory Parity: added rules for simplifying exponents.
  5075 
  5076 * Theory List:
  5077 
  5078 The following theorems have been eliminated or modified
  5079 (INCOMPATIBILITY):
  5080 
  5081   list_all_Nil       now named list_all.simps(1)
  5082   list_all_Cons      now named list_all.simps(2)
  5083   list_all_conv      now named list_all_iff
  5084   set_mem_eq         now named mem_iff
  5085 
  5086 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  5087 asymptotic "big O" calculations.  See the notes in BigO.thy.
  5088 
  5089 
  5090 *** HOL-Complex ***
  5091 
  5092 * Theory RealDef: better support for embedding natural numbers and
  5093 integers in the reals.
  5094 
  5095 The following theorems have been eliminated or modified
  5096 (INCOMPATIBILITY):
  5097 
  5098   exp_ge_add_one_self  now requires no hypotheses
  5099   real_of_int_add      reversed direction of equality (use [symmetric])
  5100   real_of_int_minus    reversed direction of equality (use [symmetric])
  5101   real_of_int_diff     reversed direction of equality (use [symmetric])
  5102   real_of_int_mult     reversed direction of equality (use [symmetric])
  5103 
  5104 * Theory RComplete: expanded support for floor and ceiling functions.
  5105 
  5106 * Theory Ln is new, with properties of the natural logarithm
  5107 
  5108 * Hyperreal: There is a new type constructor "star" for making
  5109 nonstandard types.  The old type names are now type synonyms:
  5110 
  5111   hypreal = real star
  5112   hypnat = nat star
  5113   hcomplex = complex star
  5114 
  5115 * Hyperreal: Many groups of similarly-defined constants have been
  5116 replaced by polymorphic versions (INCOMPATIBILITY):
  5117 
  5118   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  5119 
  5120   starset      <-- starsetNat, starsetC
  5121   *s*          <-- *sNat*, *sc*
  5122   starset_n    <-- starsetNat_n, starsetC_n
  5123   *sn*         <-- *sNatn*, *scn*
  5124   InternalSets <-- InternalNatSets, InternalCSets
  5125 
  5126   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  5127   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  5128   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  5129   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  5130   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  5131 
  5132 * Hyperreal: Many type-specific theorems have been removed in favor of
  5133 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  5134 
  5135   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  5136   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  5137   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  5138   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  5139   right_minus <-- hypreal_add_minus
  5140   left_minus <-- {hypreal,hcomplex}_add_minus_left
  5141   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  5142   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  5143   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  5144   mult_1_right <-- hcomplex_mult_one_right
  5145   mult_zero_left <-- hcomplex_mult_zero_left
  5146   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  5147   right_distrib <-- hypnat_add_mult_distrib2
  5148   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  5149   right_inverse <-- hypreal_mult_inverse
  5150   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  5151   order_refl <-- {hypreal,hypnat}_le_refl
  5152   order_trans <-- {hypreal,hypnat}_le_trans
  5153   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  5154   order_less_le <-- {hypreal,hypnat}_less_le
  5155   linorder_linear <-- {hypreal,hypnat}_le_linear
  5156   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  5157   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  5158   add_nonneg_nonneg <-- hypreal_le_add_order
  5159 
  5160 * Hyperreal: Separate theorems having to do with type-specific
  5161 versions of constants have been merged into theorems that apply to the
  5162 new polymorphic constants (INCOMPATIBILITY):
  5163 
  5164   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  5165   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  5166   STAR_Un <-- {STAR,NatStar,STARC}_Un
  5167   STAR_Int <-- {STAR,NatStar,STARC}_Int
  5168   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  5169   STAR_subset <-- {STAR,NatStar,STARC}_subset
  5170   STAR_mem <-- {STAR,NatStar,STARC}_mem
  5171   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  5172   STAR_diff <-- {STAR,STARC}_diff
  5173   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  5174     STARC_hcomplex_of_complex}_image_subset
  5175   starset_n_Un <-- starset{Nat,C}_n_Un
  5176   starset_n_Int <-- starset{Nat,C}_n_Int
  5177   starset_n_Compl <-- starset{Nat,C}_n_Compl
  5178   starset_n_diff <-- starset{Nat,C}_n_diff
  5179   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  5180   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  5181   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  5182   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  5183   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  5184   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  5185   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  5186   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  5187   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  5188   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  5189   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  5190   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  5191   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  5192   starfun_diff <-- starfun{C,RC,CR}_diff
  5193   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  5194   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  5195   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  5196   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  5197   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  5198   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  5199   starfun_Id <-- starfunC_Id
  5200   starfun_approx <-- starfun{Nat,CR}_approx
  5201   starfun_capprox <-- starfun{C,RC}_capprox
  5202   starfun_abs <-- starfunNat_rabs
  5203   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  5204   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  5205   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  5206   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  5207   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  5208   starfun_add_approx <-- starfunCR_add_approx
  5209   starfun_inverse_inverse <-- starfunC_inverse_inverse
  5210   starfun_divide <-- starfun{C,CR,RC}_divide
  5211   starfun_n <-- starfun{Nat,C}_n
  5212   starfun_n_mult <-- starfun{Nat,C}_n_mult
  5213   starfun_n_add <-- starfun{Nat,C}_n_add
  5214   starfun_n_add_minus <-- starfunNat_n_add_minus
  5215   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  5216   starfun_n_minus <-- starfun{Nat,C}_n_minus
  5217   starfun_n_eq <-- starfun{Nat,C}_n_eq
  5218 
  5219   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  5220   star_n_minus <-- {hypreal,hcomplex}_minus
  5221   star_n_diff <-- {hypreal,hcomplex}_diff
  5222   star_n_mult <-- {hypreal,hcomplex}_mult
  5223   star_n_inverse <-- {hypreal,hcomplex}_inverse
  5224   star_n_le <-- {hypreal,hypnat}_le
  5225   star_n_less <-- {hypreal,hypnat}_less
  5226   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  5227   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  5228   star_n_abs <-- hypreal_hrabs
  5229   star_n_divide <-- hcomplex_divide
  5230 
  5231   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  5232   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  5233   star_of_diff <-- hypreal_of_real_diff
  5234   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  5235   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  5236   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  5237   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  5238   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  5239   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  5240   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  5241   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  5242   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  5243   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  5244   star_of_number_of <-- {hypreal,hcomplex}_number_of
  5245   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  5246   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  5247   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  5248   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  5249   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  5250   star_of_power <-- hypreal_of_real_power
  5251   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  5252 
  5253 * Hyperreal: new method "transfer" that implements the transfer
  5254 principle of nonstandard analysis. With a subgoal that mentions
  5255 nonstandard types like "'a star", the command "apply transfer"
  5256 replaces it with an equivalent one that mentions only standard types.
  5257 To be successful, all free variables must have standard types; non-
  5258 standard variables must have explicit universal quantifiers.
  5259 
  5260 * Hyperreal: A theory of Taylor series.
  5261 
  5262 
  5263 *** HOLCF ***
  5264 
  5265 * Discontinued special version of 'constdefs' (which used to support
  5266 continuous functions) in favor of the general Pure one with full
  5267 type-inference.
  5268 
  5269 * New simplification procedure for solving continuity conditions; it
  5270 is much faster on terms with many nested lambda abstractions (cubic
  5271 instead of exponential time).
  5272 
  5273 * New syntax for domain package: selector names are now optional.
  5274 Parentheses should be omitted unless argument is lazy, for example:
  5275 
  5276   domain 'a stream = cons "'a" (lazy "'a stream")
  5277 
  5278 * New command 'fixrec' for defining recursive functions with pattern
  5279 matching; defining multiple functions with mutual recursion is also
  5280 supported.  Patterns may include the constants cpair, spair, up, sinl,
  5281 sinr, or any data constructor defined by the domain package. The given
  5282 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  5283 syntax and examples.
  5284 
  5285 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  5286 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  5287 but the proof obligation additionally includes an admissibility
  5288 requirement. The packages generate instances of class cpo or pcpo,
  5289 with continuity and strictness theorems for Rep and Abs.
  5290 
  5291 * HOLCF: Many theorems have been renamed according to a more standard naming
  5292 scheme (INCOMPATIBILITY):
  5293 
  5294   foo_inject:  "foo$x = foo$y ==> x = y"
  5295   foo_eq:      "(foo$x = foo$y) = (x = y)"
  5296   foo_less:    "(foo$x << foo$y) = (x << y)"
  5297   foo_strict:  "foo$UU = UU"
  5298   foo_defined: "... ==> foo$x ~= UU"
  5299   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  5300 
  5301 
  5302 *** ZF ***
  5303 
  5304 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  5305 including the First Isomorphism Theorem (on quotienting by the kernel
  5306 of a homomorphism).
  5307 
  5308 * ZF/Simplifier: install second copy of type solver that actually
  5309 makes use of TC rules declared to Isar proof contexts (or locales);
  5310 the old version is still required for ML proof scripts.
  5311 
  5312 
  5313 *** Cube ***
  5314 
  5315 * Converted to Isar theory format; use locales instead of axiomatic
  5316 theories.
  5317 
  5318 
  5319 *** ML ***
  5320 
  5321 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  5322 for ||>, ||>>, |>>,
  5323 
  5324 * Pure/library.ML no longer defines its own option datatype, but uses
  5325 that of the SML basis, which has constructors NONE and SOME instead of
  5326 None and Some, as well as exception Option.Option instead of OPTION.
  5327 The functions the, if_none, is_some, is_none have been adapted
  5328 accordingly, while Option.map replaces apsome.
  5329 
  5330 * Pure/library.ML: the exception LIST has been given up in favour of
  5331 the standard exceptions Empty and Subscript, as well as
  5332 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  5333 superceded by the standard hd and tl functions etc.
  5334 
  5335 A number of basic list functions are no longer exported to the ML
  5336 toplevel, as they are variants of predefined functions.  The following
  5337 suggests how one can translate existing code:
  5338 
  5339     rev_append xs ys = List.revAppend (xs, ys)
  5340     nth_elem (i, xs) = List.nth (xs, i)
  5341     last_elem xs = List.last xs
  5342     flat xss = List.concat xss
  5343     seq fs = List.app fs
  5344     partition P xs = List.partition P xs
  5345     mapfilter f xs = List.mapPartial f xs
  5346 
  5347 * Pure/library.ML: several combinators for linear functional
  5348 transformations, notably reverse application and composition:
  5349 
  5350   x |> f                f #> g
  5351   (x, y) |-> f          f #-> g
  5352 
  5353 * Pure/library.ML: introduced/changed precedence of infix operators:
  5354 
  5355   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  5356   infix 2 ?;
  5357   infix 3 o oo ooo oooo;
  5358   infix 4 ~~ upto downto;
  5359 
  5360 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  5361 infix operators.
  5362 
  5363 * Pure/library.ML: natural list combinators fold, fold_rev, and
  5364 fold_map support linear functional transformations and nesting.  For
  5365 example:
  5366 
  5367   fold f [x1, ..., xN] y =
  5368     y |> f x1 |> ... |> f xN
  5369 
  5370   (fold o fold) f [xs1, ..., xsN] y =
  5371     y |> fold f xs1 |> ... |> fold f xsN
  5372 
  5373   fold f [x1, ..., xN] =
  5374     f x1 #> ... #> f xN
  5375 
  5376   (fold o fold) f [xs1, ..., xsN] =
  5377     fold f xs1 #> ... #> fold f xsN
  5378 
  5379 * Pure/library.ML: the following selectors on type 'a option are
  5380 available:
  5381 
  5382   the:               'a option -> 'a  (*partial*)
  5383   these:             'a option -> 'a  where 'a = 'b list
  5384   the_default: 'a -> 'a option -> 'a
  5385   the_list:          'a option -> 'a list
  5386 
  5387 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5388 basic operations for association lists, following natural argument
  5389 order; moreover the explicit equality predicate passed here avoids
  5390 potentially expensive polymorphic runtime equality checks.
  5391 The old functions may be expressed as follows:
  5392 
  5393   assoc = uncurry (AList.lookup (op =))
  5394   assocs = these oo AList.lookup (op =)
  5395   overwrite = uncurry (AList.update (op =)) o swap
  5396 
  5397 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5398 
  5399   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  5400   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  5401 
  5402 replacing make_keylist and keyfilter (occassionally used)
  5403 Naive rewrites:
  5404 
  5405   make_keylist = AList.make
  5406   keyfilter = AList.find (op =)
  5407 
  5408 * eq_fst and eq_snd now take explicit equality parameter, thus
  5409   avoiding eqtypes. Naive rewrites:
  5410 
  5411     eq_fst = eq_fst (op =)
  5412     eq_snd = eq_snd (op =)
  5413 
  5414 * Removed deprecated apl and apr (rarely used).
  5415   Naive rewrites:
  5416 
  5417     apl (n, op) =>>= curry op n
  5418     apr (op, m) =>>= fn n => op (n, m)
  5419 
  5420 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  5421 provides a reasonably efficient light-weight implementation of sets as
  5422 lists.
  5423 
  5424 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  5425 few new operations; existing lookup and update are now curried to
  5426 follow natural argument order (for use with fold etc.);
  5427 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  5428 
  5429 * Pure/General: output via the Isabelle channels of
  5430 writeln/warning/error etc. is now passed through Output.output, with a
  5431 hook for arbitrary transformations depending on the print_mode
  5432 (cf. Output.add_mode -- the first active mode that provides a output
  5433 function wins).  Already formatted output may be embedded into further
  5434 text via Output.raw; the result of Pretty.string_of/str_of and derived
  5435 functions (string_of_term/cterm/thm etc.) is already marked raw to
  5436 accommodate easy composition of diagnostic messages etc.  Programmers
  5437 rarely need to care about Output.output or Output.raw at all, with
  5438 some notable exceptions: Output.output is required when bypassing the
  5439 standard channels (writeln etc.), or in token translations to produce
  5440 properly formatted results; Output.raw is required when capturing
  5441 already output material that will eventually be presented to the user
  5442 a second time.  For the default print mode, both Output.output and
  5443 Output.raw have no effect.
  5444 
  5445 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  5446 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  5447 cumulative results are displayed at the end of a batch session.
  5448 
  5449 * Pure/General: File.sysify_path and File.quote_sysify path have been
  5450 replaced by File.platform_path and File.shell_path (with appropriate
  5451 hooks).  This provides a clean interface for unusual systems where the
  5452 internal and external process view of file names are different.
  5453 
  5454 * Pure: more efficient orders for basic syntactic entities: added
  5455 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  5456 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  5457 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  5458 orders now -- potential INCOMPATIBILITY for code that depends on a
  5459 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  5460 Library.sort_strings on result).
  5461 
  5462 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  5463 fold_types traverse types/terms from left to right, observing natural
  5464 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  5465 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  5466 
  5467 * Pure: name spaces have been refined, with significant changes of the
  5468 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  5469 to extern(_table).  The plain name entry path is superceded by a
  5470 general 'naming' context, which also includes the 'policy' to produce
  5471 a fully qualified name and external accesses of a fully qualified
  5472 name; NameSpace.extend is superceded by context dependent
  5473 Sign.declare_name.  Several theory and proof context operations modify
  5474 the naming context.  Especially note Theory.restore_naming and
  5475 ProofContext.restore_naming to get back to a sane state; note that
  5476 Theory.add_path is no longer sufficient to recover from
  5477 Theory.absolute_path in particular.
  5478 
  5479 * Pure: new flags short_names (default false) and unique_names
  5480 (default true) for controlling output of qualified names.  If
  5481 short_names is set, names are printed unqualified.  If unique_names is
  5482 reset, the name prefix is reduced to the minimum required to achieve
  5483 the original result when interning again, even if there is an overlap
  5484 with earlier declarations.
  5485 
  5486 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  5487 now 'extend', and 'merge' gets an additional Pretty.pp argument
  5488 (useful for printing error messages).  INCOMPATIBILITY.
  5489 
  5490 * Pure: major reorganization of the theory context.  Type Sign.sg and
  5491 Theory.theory are now identified, referring to the universal
  5492 Context.theory (see Pure/context.ML).  Actual signature and theory
  5493 content is managed as theory data.  The old code and interfaces were
  5494 spread over many files and structures; the new arrangement introduces
  5495 considerable INCOMPATIBILITY to gain more clarity:
  5496 
  5497   Context -- theory management operations (name, identity, inclusion,
  5498     parents, ancestors, merge, etc.), plus generic theory data;
  5499 
  5500   Sign -- logical signature and syntax operations (declaring consts,
  5501     types, etc.), plus certify/read for common entities;
  5502 
  5503   Theory -- logical theory operations (stating axioms, definitions,
  5504     oracles), plus a copy of logical signature operations (consts,
  5505     types, etc.); also a few basic management operations (Theory.copy,
  5506     Theory.merge, etc.)
  5507 
  5508 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  5509 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  5510 for convenience -- they merely return the theory.
  5511 
  5512 * Pure: type Type.tsig is superceded by theory in most interfaces.
  5513 
  5514 * Pure: the Isar proof context type is already defined early in Pure
  5515 as Context.proof (note that ProofContext.context and Proof.context are
  5516 aliases, where the latter is the preferred name).  This enables other
  5517 Isabelle components to refer to that type even before Isar is present.
  5518 
  5519 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  5520 typeK, constK, axiomK, oracleK), but provide explicit operations for
  5521 any of these kinds.  For example, Sign.intern typeK is now
  5522 Sign.intern_type, Theory.hide_space Sign.typeK is now
  5523 Theory.hide_types.  Also note that former
  5524 Theory.hide_classes/types/consts are now
  5525 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  5526 internalize their arguments!  INCOMPATIBILITY.
  5527 
  5528 * Pure: get_thm interface (of PureThy and ProofContext) expects
  5529 datatype thmref (with constructors Name and NameSelection) instead of
  5530 plain string -- INCOMPATIBILITY;
  5531 
  5532 * Pure: cases produced by proof methods specify options, where NONE
  5533 means to remove case bindings -- INCOMPATIBILITY in
  5534 (RAW_)METHOD_CASES.
  5535 
  5536 * Pure: the following operations retrieve axioms or theorems from a
  5537 theory node or theory hierarchy, respectively:
  5538 
  5539   Theory.axioms_of: theory -> (string * term) list
  5540   Theory.all_axioms_of: theory -> (string * term) list
  5541   PureThy.thms_of: theory -> (string * thm) list
  5542   PureThy.all_thms_of: theory -> (string * thm) list
  5543 
  5544 * Pure: print_tac now outputs the goal through the trace channel.
  5545 
  5546 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  5547 Reference Toplevel.debug (default false) controls detailed printing
  5548 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  5549 controls execution profiling -- set to 1 for time and 2 for space
  5550 (both increase the runtime).
  5551 
  5552 * Isar session: The initial use of ROOT.ML is now always timed,
  5553 i.e. the log will show the actual process times, in contrast to the
  5554 elapsed wall-clock time that the outer shell wrapper produces.
  5555 
  5556 * Simplifier: improved handling of bound variables (nameless
  5557 representation, avoid allocating new strings).  Simprocs that invoke
  5558 the Simplifier recursively should use Simplifier.inherit_bounds to
  5559 avoid local name clashes.  Failure to do so produces warnings
  5560 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  5561 for further details.
  5562 
  5563 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  5564 bindings for all theorems stored within a given theory; this may help
  5565 in porting non-Isar theories to Isar ones, while keeping ML proof
  5566 scripts for the time being.
  5567 
  5568 * ML operator HTML.with_charset specifies the charset begin used for
  5569 generated HTML files.  For example:
  5570 
  5571   HTML.with_charset "utf-8" use_thy "Hebrew";
  5572   HTML.with_charset "utf-8" use_thy "Chinese";
  5573 
  5574 
  5575 *** System ***
  5576 
  5577 * Allow symlinks to all proper Isabelle executables (Isabelle,
  5578 isabelle, isatool etc.).
  5579 
  5580 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  5581 isatool doc, isatool mkdir, display_drafts etc.).
  5582 
  5583 * isatool usedir: option -f allows specification of the ML file to be
  5584 used by Isabelle; default is ROOT.ML.
  5585 
  5586 * New isatool version outputs the version identifier of the Isabelle
  5587 distribution being used.
  5588 
  5589 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  5590 (containing Boolean satisfiability problems) into Isabelle/HOL
  5591 theories.
  5592 
  5593 
  5594 
  5595 New in Isabelle2004 (April 2004)
  5596 --------------------------------
  5597 
  5598 *** General ***
  5599 
  5600 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  5601   Replaces linorder.ML.
  5602 
  5603 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  5604   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  5605   (\<a>...\<z>), are now considered normal letters, and can therefore
  5606   be used anywhere where an ASCII letter (a...zA...Z) has until
  5607   now. COMPATIBILITY: This obviously changes the parsing of some
  5608   terms, especially where a symbol has been used as a binder, say
  5609   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  5610   as an identifier.  Fix it by inserting a space around former
  5611   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  5612   existing theory and ML files.
  5613 
  5614 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  5615 
  5616 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  5617   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  5618   a normal (but invisible) letter. For multiple letter subscripts repeat
  5619   \<^isub> like this: x\<^isub>1\<^isub>2.
  5620 
  5621 * Pure: There are now sub-/superscripts that can span more than one
  5622   character. Text between \<^bsub> and \<^esub> is set in subscript in
  5623   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  5624   superscript. The new control characters are not identifier parts.
  5625 
  5626 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5627   content of "..." to the latex file instead of \isacntrl... . The "..."
  5628   may consist of any printable characters excluding the end bracket >.
  5629 
  5630 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5631   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5632   declare constants "final", which prevents their being given a definition
  5633   later.  It is useful for constants whose behaviour is fixed axiomatically
  5634   rather than definitionally, such as the meta-logic connectives.
  5635 
  5636 * Pure: 'instance' now handles general arities with general sorts
  5637   (i.e. intersections of classes),
  5638 
  5639 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5640   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5641   It can be changed to alter the colors/layout of generated pages.
  5642 
  5643 
  5644 *** Isar ***
  5645 
  5646 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5647   cut_tac, subgoal_tac and thin_tac:
  5648   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5649     locales are no longer forced to write Isar proof scripts.
  5650     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5651     emulations.
  5652   - INCOMPATIBILITY: names of variables to be instantiated may no
  5653     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5654     This is consistent with the instantiation attribute "where".
  5655 
  5656 * Attributes "where" and "of":
  5657   - Now take type variables of instantiated theorem into account when reading
  5658     the instantiation string.  This fixes a bug that caused instantiated
  5659     theorems to have too special types in some circumstances.
  5660   - "where" permits explicit instantiations of type variables.
  5661 
  5662 * Calculation commands "moreover" and "also" no longer interfere with
  5663   current facts ("this"), admitting arbitrary combinations with "then"
  5664   and derived forms.
  5665 
  5666 * Locales:
  5667   - Goal statements involving the context element "includes" no longer
  5668     generate theorems with internal delta predicates (those ending on
  5669     "_axioms") in the premise.
  5670     Resolve particular premise with <locale>.intro to obtain old form.
  5671   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5672     specification and "includes" elements in goal statement.
  5673   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5674     [intro?] and [elim?] (respectively) by default.
  5675   - Experimental command for instantiation of locales in proof contexts:
  5676         instantiate <label>[<attrs>]: <loc>
  5677     Instantiates locale <loc> and adds all its theorems to the current context
  5678     taking into account their attributes.  Label and attrs are optional
  5679     modifiers, like in theorem declarations.  If present, names of
  5680     instantiated theorems are qualified with <label>, and the attributes
  5681     <attrs> are applied after any attributes these theorems might have already.
  5682       If the locale has assumptions, a chained fact of the form
  5683     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5684     are derived.  The command does not support old-style locales declared
  5685     with "locale (open)".
  5686       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5687 
  5688 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5689   (Isar) contexts.
  5690 
  5691 
  5692 *** HOL ***
  5693 
  5694 * Proof import: new image HOL4 contains the imported library from
  5695   the HOL4 system with about 2500 theorems. It is imported by
  5696   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5697   can be used like any other Isabelle image.  See
  5698   HOL/Import/HOL/README for more information.
  5699 
  5700 * Simplifier:
  5701   - Much improved handling of linear and partial orders.
  5702     Reasoners for linear and partial orders are set up for type classes
  5703     "linorder" and "order" respectively, and are added to the default simpset
  5704     as solvers.  This means that the simplifier can build transitivity chains
  5705     to solve goals from the assumptions.
  5706   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5707     of blast or auto after simplification become unnecessary because the goal
  5708     is solved by simplification already.
  5709 
  5710 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5711     all proved in axiomatic type classes for semirings, rings and fields.
  5712 
  5713 * Numerics:
  5714   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5715     now formalized using the Ring_and_Field theory mentioned above.
  5716   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5717     than before, because now they are set up once in a generic manner.
  5718   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5719     Look for the general versions in Ring_and_Field (and Power if they concern
  5720     exponentiation).
  5721 
  5722 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5723 
  5724 * Records:
  5725   - Record types are now by default printed with their type abbreviation
  5726     instead of the list of all field types. This can be configured via
  5727     the reference "print_record_type_abbr".
  5728   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5729     (not enabled by default).
  5730   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5731     EX x. x = sel r to True (not enabled by default).
  5732   - Tactic "record_split_simp_tac" to split and simplify records added.
  5733 
  5734 * 'specification' command added, allowing for definition by
  5735   specification.  There is also an 'ax_specification' command that
  5736   introduces the new constants axiomatically.
  5737 
  5738 * arith(_tac) is now able to generate counterexamples for reals as well.
  5739 
  5740 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5741 
  5742 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5743   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5744 
  5745 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5746   matrix theory to linear programming.
  5747 
  5748 * Unions and Intersections:
  5749   The latex output syntax of UN and INT has been changed
  5750   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5751   i.e. the index formulae has become a subscript.
  5752   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5753 
  5754 * Unions and Intersections over Intervals:
  5755   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5756   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5757   like in normal math, and corresponding versions for < and for intersection.
  5758 
  5759 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5760   lexicographic dictonary ordering has been added as "lexord".
  5761 
  5762 * ML: the legacy theory structures Int and List have been removed. They had
  5763   conflicted with ML Basis Library structures having the same names.
  5764 
  5765 * 'refute' command added to search for (finite) countermodels.  Only works
  5766   for a fragment of HOL.  The installation of an external SAT solver is
  5767   highly recommended.  See "HOL/Refute.thy" for details.
  5768 
  5769 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5770   formulae under an assignment of free variables to random values.
  5771   In contrast to 'refute', it can deal with inductive datatypes,
  5772   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5773   for examples.
  5774 
  5775 
  5776 *** HOLCF ***
  5777 
  5778 * Streams now come with concatenation and are part of the HOLCF image
  5779 
  5780 
  5781 
  5782 New in Isabelle2003 (May 2003)
  5783 ------------------------------
  5784 
  5785 *** General ***
  5786 
  5787 * Provers/simplifier:
  5788 
  5789   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5790     Assumptions are now subject to complete mutual simplification,
  5791     not just from left to right. The simplifier now preserves
  5792     the order of assumptions.
  5793 
  5794     Potential INCOMPATIBILITY:
  5795 
  5796     -- simp sometimes diverges where the old version did
  5797        not, e.g. invoking simp on the goal
  5798 
  5799         [| P (f x); y = x; f x = f y |] ==> Q
  5800 
  5801        now gives rise to the infinite reduction sequence
  5802 
  5803         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5804 
  5805        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5806        kind of problem.
  5807 
  5808     -- Tactics combining classical reasoner and simplification (such as auto)
  5809        are also affected by this change, because many of them rely on
  5810        simp. They may sometimes diverge as well or yield a different numbers
  5811        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5812        in case of problems. Sometimes subsequent calls to the classical
  5813        reasoner will fail because a preceeding call to the simplifier too
  5814        eagerly simplified the goal, e.g. deleted redundant premises.
  5815 
  5816   - The simplifier trace now shows the names of the applied rewrite rules
  5817 
  5818   - You can limit the number of recursive invocations of the simplifier
  5819     during conditional rewriting (where the simplifie tries to solve the
  5820     conditions before applying the rewrite rule):
  5821     ML "simp_depth_limit := n"
  5822     where n is an integer. Thus you can force termination where previously
  5823     the simplifier would diverge.
  5824 
  5825   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5826 
  5827   - No longer aborts on failed congruence proof.  Instead, the
  5828     congruence is ignored.
  5829 
  5830 * Pure: New generic framework for extracting programs from constructive
  5831   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5832   as HOL/Extraction for some case studies.
  5833 
  5834 * Pure: The main goal of the proof state is no longer shown by default, only
  5835 the subgoals. This behaviour is controlled by a new flag.
  5836    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5837 (ML: Proof.show_main_goal).
  5838 
  5839 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5840 rules whose conclusion matches subgoal 1:
  5841       PG menu: Isabelle/Isar -> Show me -> matching rules
  5842 The rules are ordered by how closely they match the subgoal.
  5843 In particular, rules that solve a subgoal outright are displayed first
  5844 (or rather last, the way they are printed).
  5845 (ML: ProofGeneral.print_intros())
  5846 
  5847 * Pure: New flag trace_unify_fail causes unification to print
  5848 diagnostic information (PG: in trace buffer) when it fails. This is
  5849 useful for figuring out why single step proofs like rule, erule or
  5850 assumption failed.
  5851 
  5852 * Pure: Locale specifications now produce predicate definitions
  5853 according to the body of text (covering assumptions modulo local
  5854 definitions); predicate "loc_axioms" covers newly introduced text,
  5855 while "loc" is cumulative wrt. all included locale expressions; the
  5856 latter view is presented only on export into the global theory
  5857 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5858 on the old view without predicates;
  5859 
  5860 * Pure: predefined locales "var" and "struct" are useful for sharing
  5861 parameters (as in CASL, for example); just specify something like
  5862 ``var x + var y + struct M'' as import;
  5863 
  5864 * Pure: improved thms_containing: proper indexing of facts instead of
  5865 raw theorems; check validity of results wrt. current name space;
  5866 include local facts of proof configuration (also covers active
  5867 locales), cover fixed variables in index; may use "_" in term
  5868 specification; an optional limit for the number of printed facts may
  5869 be given (the default is 40);
  5870 
  5871 * Pure: disallow duplicate fact bindings within new-style theory files
  5872 (batch-mode only);
  5873 
  5874 * Provers: improved induct method: assumptions introduced by case
  5875 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5876 the goal statement); "foo" still refers to all facts collectively;
  5877 
  5878 * Provers: the function blast.overloaded has been removed: all constants
  5879 are regarded as potentially overloaded, which improves robustness in exchange
  5880 for slight decrease in efficiency;
  5881 
  5882 * Provers/linorder: New generic prover for transitivity reasoning over
  5883 linear orders.  Note: this prover is not efficient!
  5884 
  5885 * Isar: preview of problems to finish 'show' now produce an error
  5886 rather than just a warning (in interactive mode);
  5887 
  5888 
  5889 *** HOL ***
  5890 
  5891 * arith(_tac)
  5892 
  5893  - Produces a counter example if it cannot prove a goal.
  5894    Note that the counter example may be spurious if the goal is not a formula
  5895    of quantifier-free linear arithmetic.
  5896    In ProofGeneral the counter example appears in the trace buffer.
  5897 
  5898  - Knows about div k and mod k where k is a numeral of type nat or int.
  5899 
  5900  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  5901    linear arithmetic fails. This takes account of quantifiers and divisibility.
  5902    Presburger arithmetic can also be called explicitly via presburger(_tac).
  5903 
  5904 * simp's arithmetic capabilities have been enhanced a bit: it now
  5905 takes ~= in premises into account (by performing a case split);
  5906 
  5907 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  5908 are distributed over a sum of terms;
  5909 
  5910 * New tactic "trans_tac" and method "trans" instantiate
  5911 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  5912 "<=", "<" and "=").
  5913 
  5914 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  5915 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  5916 
  5917 * 'typedef' command has new option "open" to suppress the set
  5918 definition;
  5919 
  5920 * functions Min and Max on finite sets have been introduced (theory
  5921 Finite_Set);
  5922 
  5923 * attribute [symmetric] now works for relations as well; it turns
  5924 (x,y) : R^-1 into (y,x) : R, and vice versa;
  5925 
  5926 * induct over a !!-quantified statement (say !!x1..xn):
  5927   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  5928 
  5929 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  5930 %x. None. Warning: empty_def now refers to the previously hidden definition
  5931 of the empty set.
  5932 
  5933 * Algebra: formalization of classical algebra.  Intended as base for
  5934 any algebraic development in Isabelle.  Currently covers group theory
  5935 (up to Sylow's theorem) and ring theory (Universal Property of
  5936 Univariate Polynomials).  Contributions welcome;
  5937 
  5938 * GroupTheory: deleted, since its material has been moved to Algebra;
  5939 
  5940 * Complex: new directory of the complex numbers with numeric constants,
  5941 nonstandard complex numbers, and some complex analysis, standard and
  5942 nonstandard (Jacques Fleuriot);
  5943 
  5944 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  5945 
  5946 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  5947 Fleuriot);
  5948 
  5949 * Real/HahnBanach: updated and adapted to locales;
  5950 
  5951 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  5952 Gray and Kramer);
  5953 
  5954 * UNITY: added the Meier-Sanders theory of progress sets;
  5955 
  5956 * MicroJava: bytecode verifier and lightweight bytecode verifier
  5957 as abstract algorithms, instantiated to the JVM;
  5958 
  5959 * Bali: Java source language formalization. Type system, operational
  5960 semantics, axiomatic semantics. Supported language features:
  5961 classes, interfaces, objects,virtual methods, static methods,
  5962 static/instance fields, arrays, access modifiers, definite
  5963 assignment, exceptions.
  5964 
  5965 
  5966 *** ZF ***
  5967 
  5968 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  5969 universe, etc.);
  5970 
  5971 * Main ZF: virtually all theories converted to new-style format;
  5972 
  5973 
  5974 *** ML ***
  5975 
  5976 * Pure: Tactic.prove provides sane interface for internal proofs;
  5977 omits the infamous "standard" operation, so this is more appropriate
  5978 than prove_goalw_cterm in many situations (e.g. in simprocs);
  5979 
  5980 * Pure: improved error reporting of simprocs;
  5981 
  5982 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  5983 up simprocs;
  5984 
  5985 
  5986 *** Document preparation ***
  5987 
  5988 * uses \par instead of \\ for line breaks in theory text. This may
  5989 shift some page breaks in large documents. To get the old behaviour
  5990 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  5991 
  5992 * minimized dependencies of isabelle.sty and isabellesym.sty on
  5993 other packages
  5994 
  5995 * \<euro> now needs package babel/greek instead of marvosym (which
  5996 broke \Rightarrow)
  5997 
  5998 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  5999 textcomp package)
  6000 
  6001 
  6002 
  6003 New in Isabelle2002 (March 2002)
  6004 --------------------------------
  6005 
  6006 *** Document preparation ***
  6007 
  6008 * greatly simplified document preparation setup, including more
  6009 graceful interpretation of isatool usedir -i/-d/-D options, and more
  6010 instructive isatool mkdir; users should basically be able to get
  6011 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  6012 users may run a separate document processing stage manually like this:
  6013 "isatool usedir -D output HOL Test && isatool document Test/output";
  6014 
  6015 * theory dependency graph may now be incorporated into documents;
  6016 isatool usedir -g true will produce session_graph.eps/.pdf for use
  6017 with \includegraphics of LaTeX;
  6018 
  6019 * proper spacing of consecutive markup elements, especially text
  6020 blocks after section headings;
  6021 
  6022 * support bold style (for single symbols only), input syntax is like
  6023 this: "\<^bold>\<alpha>" or "\<^bold>A";
  6024 
  6025 * \<bullet> is now output as bold \cdot by default, which looks much
  6026 better in printed text;
  6027 
  6028 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  6029 note that these symbols are currently unavailable in Proof General /
  6030 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  6031 
  6032 * isatool latex no longer depends on changed TEXINPUTS, instead
  6033 isatool document copies the Isabelle style files to the target
  6034 location;
  6035 
  6036 
  6037 *** Isar ***
  6038 
  6039 * Pure/Provers: improved proof by cases and induction;
  6040   - 'case' command admits impromptu naming of parameters (such as
  6041     "case (Suc n)");
  6042   - 'induct' method divinates rule instantiation from the inductive
  6043     claim; no longer requires excessive ?P bindings for proper
  6044     instantiation of cases;
  6045   - 'induct' method properly enumerates all possibilities of set/type
  6046     rules; as a consequence facts may be also passed through *type*
  6047     rules without further ado;
  6048   - 'induct' method now derives symbolic cases from the *rulified*
  6049     rule (before it used to rulify cases stemming from the internal
  6050     atomized version); this means that the context of a non-atomic
  6051     statement becomes is included in the hypothesis, avoiding the
  6052     slightly cumbersome show "PROP ?case" form;
  6053   - 'induct' may now use elim-style induction rules without chaining
  6054     facts, using ``missing'' premises from the goal state; this allows
  6055     rules stemming from inductive sets to be applied in unstructured
  6056     scripts, while still benefitting from proper handling of non-atomic
  6057     statements; NB: major inductive premises need to be put first, all
  6058     the rest of the goal is passed through the induction;
  6059   - 'induct' proper support for mutual induction involving non-atomic
  6060     rule statements (uses the new concept of simultaneous goals, see
  6061     below);
  6062   - append all possible rule selections, but only use the first
  6063     success (no backtracking);
  6064   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  6065   - undeclared rule case names default to numbers 1, 2, 3, ...;
  6066   - added 'print_induct_rules' (covered by help item in recent Proof
  6067     General versions);
  6068   - moved induct/cases attributes to Pure, methods to Provers;
  6069   - generic method setup instantiated for FOL and HOL;
  6070 
  6071 * Pure: support multiple simultaneous goal statements, for example
  6072 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  6073 meta-level mechanism, this acts as if several individual goals had
  6074 been stated separately; in particular common proof methods need to be
  6075 repeated in order to cover all claims; note that a single elimination
  6076 step is *not* sufficient to establish the two conjunctions, so this
  6077 fails:
  6078 
  6079   assume "A & B" then have A and B ..   (*".." fails*)
  6080 
  6081 better use "obtain" in situations as above; alternative refer to
  6082 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  6083 
  6084 * Pure: proper integration with ``locales''; unlike the original
  6085 version by Florian Kammller, Isar locales package high-level proof
  6086 contexts rather than raw logical ones (e.g. we admit to include
  6087 attributes everywhere); operations on locales include merge and
  6088 rename; support for implicit arguments (``structures''); simultaneous
  6089 type-inference over imports and text; see also HOL/ex/Locales.thy for
  6090 some examples;
  6091 
  6092 * Pure: the following commands have been ``localized'', supporting a
  6093 target locale specification "(in name)": 'lemma', 'theorem',
  6094 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  6095 stored both within the locale and at the theory level (exported and
  6096 qualified by the locale name);
  6097 
  6098 * Pure: theory goals may now be specified in ``long'' form, with
  6099 ad-hoc contexts consisting of arbitrary locale elements. for example
  6100 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  6101 definitions may be given, too); the result is a meta-level rule with
  6102 the context elements being discharged in the obvious way;
  6103 
  6104 * Pure: new proof command 'using' allows to augment currently used
  6105 facts after a goal statement ('using' is syntactically analogous to
  6106 'apply', but acts on the goal's facts only); this allows chained facts
  6107 to be separated into parts given before and after a claim, as in
  6108 ``from a and b have C using d and e <proof>'';
  6109 
  6110 * Pure: renamed "antecedent" case to "rule_context";
  6111 
  6112 * Pure: new 'judgment' command records explicit information about the
  6113 object-logic embedding (used by several tools internally); no longer
  6114 use hard-wired "Trueprop";
  6115 
  6116 * Pure: added 'corollary' command;
  6117 
  6118 * Pure: fixed 'token_translation' command;
  6119 
  6120 * Pure: removed obsolete 'exported' attribute;
  6121 
  6122 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  6123 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  6124 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  6125 
  6126 * Pure: method 'atomize' presents local goal premises as object-level
  6127 statements (atomic meta-level propositions); setup controlled via
  6128 rewrite rules declarations of 'atomize' attribute; example
  6129 application: 'induct' method with proper rule statements in improper
  6130 proof *scripts*;
  6131 
  6132 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  6133 now consider the syntactic context of assumptions, giving a better
  6134 chance to get type-inference of the arguments right (this is
  6135 especially important for locales);
  6136 
  6137 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  6138 mode;
  6139 
  6140 * Pure/obtain: the formal conclusion "thesis", being marked as
  6141 ``internal'', may no longer be reference directly in the text;
  6142 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  6143 situations;
  6144 
  6145 * Pure: generic 'sym' attribute which declares a rule both as pure
  6146 'elim?' and for the 'symmetric' operation;
  6147 
  6148 * Pure: marginal comments ``--'' may now occur just anywhere in the
  6149 text; the fixed correlation with particular command syntax has been
  6150 discontinued;
  6151 
  6152 * Pure: new method 'rules' is particularly well-suited for proof
  6153 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  6154 but often produces more compact proof terms with less detours;
  6155 
  6156 * Pure/Provers/classical: simplified integration with pure rule
  6157 attributes and methods; the classical "intro?/elim?/dest?"
  6158 declarations coincide with the pure ones; the "rule" method no longer
  6159 includes classically swapped intros; "intro" and "elim" methods no
  6160 longer pick rules from the context; also got rid of ML declarations
  6161 AddXIs/AddXEs/AddXDs; all of this has some potential for
  6162 INCOMPATIBILITY;
  6163 
  6164 * Provers/classical: attribute 'swapped' produces classical inversions
  6165 of introduction rules;
  6166 
  6167 * Provers/simplifier: 'simplified' attribute may refer to explicit
  6168 rules instead of full simplifier context; 'iff' attribute handles
  6169 conditional rules;
  6170 
  6171 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  6172 
  6173 * HOL: 'recdef' now fails on unfinished automated proofs, use
  6174 "(permissive)" option to recover old behavior;
  6175 
  6176 * HOL: 'inductive' no longer features separate (collective) attributes
  6177 for 'intros' (was found too confusing);
  6178 
  6179 * HOL: properly declared induction rules less_induct and
  6180 wf_induct_rule;
  6181 
  6182 
  6183 *** HOL ***
  6184 
  6185 * HOL: moved over to sane numeral syntax; the new policy is as
  6186 follows:
  6187 
  6188   - 0 and 1 are polymorphic constants, which are defined on any
  6189   numeric type (nat, int, real etc.);
  6190 
  6191   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  6192   binary representation internally;
  6193 
  6194   - type nat has special constructor Suc, and generally prefers Suc 0
  6195   over 1::nat and Suc (Suc 0) over 2::nat;
  6196 
  6197 This change may cause significant problems of INCOMPATIBILITY; here
  6198 are some hints on converting existing sources:
  6199 
  6200   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  6201   entities, so expressions involving "-" (unary or binary minus) need
  6202   to be spaced properly;
  6203 
  6204   - existing occurrences of "1" may need to be constraint "1::nat" or
  6205   even replaced by Suc 0; similar for old "2";
  6206 
  6207   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  6208 
  6209   - remove all special provisions on numerals in proofs;
  6210 
  6211 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  6212 representation (depends on bin_arith_simps in the default context);
  6213 
  6214 * HOL: symbolic syntax for x^2 (numeral 2);
  6215 
  6216 * HOL: the class of all HOL types is now called "type" rather than
  6217 "term"; INCOMPATIBILITY, need to adapt references to this type class
  6218 in axclass/classes, instance/arities, and (usually rare) occurrences
  6219 in typings (of consts etc.); internally the class is called
  6220 "HOL.type", ML programs should refer to HOLogic.typeS;
  6221 
  6222 * HOL/record package improvements:
  6223   - new derived operations "fields" to build a partial record section,
  6224     "extend" to promote a fixed record to a record scheme, and
  6225     "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*
  6226     declared as simp by default;
  6227   - shared operations ("more", "fields", etc.) now need to be always
  6228     qualified) --- potential INCOMPATIBILITY;
  6229   - removed "make_scheme" operations (use "make" with "extend") --
  6230     INCOMPATIBILITY;
  6231   - removed "more" class (simply use "term") -- INCOMPATIBILITY;