NEWS
author blanchet
Mon Jun 06 20:36:35 2011 +0200 (2011-06-06)
changeset 43206 831d28439b3a
parent 42897 6bc8a6dcb3e0
child 43228 2ed2f092e990
permissions -rw-r--r--
marked "metisF" as legacy -- nobody uses it or needs it
     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: more coherent development of fold_set locales:
    62 
    63     locale fun_left_comm ~> locale comp_fun_commute
    64     locale fun_left_comm_idem ~> locale comp_fun_idem
    65     
    66 Both use point-free characterisation; interpretation proofs may need adjustment.
    67 INCOMPATIBILITY.
    68 
    69 * Code generation:
    70   - theory Library/Code_Char_ord provides native ordering of characters
    71     in the target language.
    72     
    73 * Declare ext [intro] by default.  Rare INCOMPATIBILITY.
    74 
    75 * Nitpick:
    76   - Added "need" and "total_consts" options.
    77   - Reintroduced "show_skolems" option by popular demand.
    78   - Renamed attribute: nitpick_def ~> nitpick_unfold.
    79     INCOMPATIBILITY.
    80 
    81 * Sledgehammer:
    82   - sledgehammer available_provers ~> sledgehammer supported_provers
    83     INCOMPATIBILITY.
    84   - Added support for SNARK and ToFoF-E on SystemOnTPTP and for simply typed
    85     TPTP problems (TFF).
    86   - Added "type_sys", "max_mono_iters", and "max_new_mono_instances" options.
    87 
    88 * Metis:
    89   - Obsoleted "metisF" -- use "metis" instead.
    90 
    91 * "try":
    92   - Added "simp:", "intro:", and "elim:" options.
    93 
    94 * Quickcheck:
    95   - Added "eval" option to evaluate terms for the found counterexample
    96     (currently only supported by the default (exhaustive) tester)
    97   - Added post-processing of terms to obtain readable counterexamples
    98     (currently only supported by the default (exhaustive) tester)
    99 
   100 * Function package: discontinued option "tailrec".
   101 INCOMPATIBILITY. Use partial_function instead.
   102 
   103 * HOL-Probability:
   104   - Caratheodory's extension lemma is now proved for ring_of_sets.
   105   - Infinite products of probability measures are now available.
   106   - Use extended reals instead of positive extended reals.
   107     INCOMPATIBILITY.
   108 
   109 
   110 *** Document preparation ***
   111 
   112 * Antiquotation @{rail} layouts railroad syntax diagrams, see also
   113 isar-ref manual.
   114 
   115 * Localized \isabellestyle switch can be used within blocks or groups
   116 like this:
   117 
   118   \isabellestyle{it}  %preferred default
   119   {\isabellestylett @{text "typewriter stuff"}}
   120 
   121 * New term style "isub" as ad-hoc conversion of variables x1, y23 into
   122 subscripted form x\<^isub>1, y\<^isub>2\<^isub>3.
   123 
   124 * Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
   125 (e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).
   126 
   127 
   128 *** ML ***
   129 
   130 * Isabelle_Process.is_active allows tools to check if the official
   131 process wrapper is running (Isabelle/Scala/jEdit) or the old TTY loop
   132 (better known as Proof General).
   133 
   134 * Structure Proof_Context follows standard naming scheme.  Old
   135 ProofContext is still available for some time as legacy alias.
   136 
   137 * Structure Timing provides various operations for timing; supersedes
   138 former start_timing/end_timing etc.
   139 
   140 * Path.print is the official way to show file-system paths to users
   141 (including quotes etc.).
   142 
   143 * Inner syntax: identifiers in parse trees of generic categories
   144 "logic", "aprop", "idt" etc. carry position information (disguised as
   145 type constraints).  Occasional INCOMPATIBILITY with non-compliant
   146 translations that choke on unexpected type constraints.  Positions can
   147 be stripped in ML translations via Syntax.strip_positions /
   148 Syntax.strip_positions_ast, or via the syntax constant
   149 "_strip_positions" within parse trees.  As last resort, positions can
   150 be disabled via the configuration option Syntax.positions, which is
   151 called "syntax_positions" in Isar attribute syntax.
   152 
   153 * Discontinued special status of various ML structures that contribute
   154 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
   155 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
   156 refer directly to Ast.Constant, Lexicon.is_identifier,
   157 Syntax_Trans.mk_binder_tr etc.
   158 
   159 * Typed print translation: discontinued show_sorts argument, which is
   160 already available via context of "advanced" translation.
   161 
   162 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
   163 goal states; body tactic needs to address all subgoals uniformly.
   164 
   165 * Slightly more special eq_list/eq_set, with shortcut involving
   166 pointer equality (assumes that eq relation is reflexive).
   167 
   168 * Classical tactics use proper Proof.context instead of historic types
   169 claset/clasimpset.  Old-style declarations like addIs, addEs, addDs
   170 operate directly on Proof.context.  Raw type claset retains its use as
   171 snapshot of the classical context, which can be recovered via
   172 (put_claset HOL_cs) etc.  Type clasimpset has been discontinued.
   173 INCOMPATIBILITY, classical tactics and derived proof methods require
   174 proper Proof.context.
   175 
   176 
   177 
   178 New in Isabelle2011 (January 2011)
   179 ----------------------------------
   180 
   181 *** General ***
   182 
   183 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
   184 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
   185 useful tooltips and hyperlinks produced from its static analysis.  The
   186 bundled component provides an executable Isabelle tool that can be run
   187 like this:
   188 
   189   Isabelle2011/bin/isabelle jedit
   190 
   191 * Significantly improved Isabelle/Isar implementation manual.
   192 
   193 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
   194 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
   195 while the default heap location within that directory lacks that extra
   196 suffix.  This isolates multiple Isabelle installations from each
   197 other, avoiding problems with old settings in new versions.
   198 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
   199 
   200 * Source files are always encoded as UTF-8, instead of old-fashioned
   201 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
   202 the following package declarations:
   203 
   204   \usepackage[utf8]{inputenc}
   205   \usepackage{textcomp}
   206 
   207 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
   208 a Unicode character is treated as a single symbol, not a sequence of
   209 non-ASCII bytes as before.  Since Isabelle/ML string literals may
   210 contain symbols without further backslash escapes, Unicode can now be
   211 used here as well.  Recall that Symbol.explode in ML provides a
   212 consistent view on symbols, while raw explode (or String.explode)
   213 merely give a byte-oriented representation.
   214 
   215 * Theory loader: source files are primarily located via the master
   216 directory of each theory node (where the .thy file itself resides).
   217 The global load path is still partially available as legacy feature.
   218 Minor INCOMPATIBILITY due to subtle change in file lookup: use
   219 explicit paths, relatively to the theory.
   220 
   221 * Special treatment of ML file names has been discontinued.
   222 Historically, optional extensions .ML or .sml were added on demand --
   223 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
   224 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
   225 
   226 * Various options that affect pretty printing etc. are now properly
   227 handled within the context via configuration options, instead of
   228 unsynchronized references or print modes.  There are both ML Config.T
   229 entities and Isar declaration attributes to access these.
   230 
   231   ML (Config.T)                 Isar (attribute)
   232 
   233   eta_contract                  eta_contract
   234   show_brackets                 show_brackets
   235   show_sorts                    show_sorts
   236   show_types                    show_types
   237   show_question_marks           show_question_marks
   238   show_consts                   show_consts
   239   show_abbrevs                  show_abbrevs
   240 
   241   Syntax.ast_trace              syntax_ast_trace
   242   Syntax.ast_stat               syntax_ast_stat
   243   Syntax.ambiguity_level        syntax_ambiguity_level
   244 
   245   Goal_Display.goals_limit      goals_limit
   246   Goal_Display.show_main_goal   show_main_goal
   247 
   248   Method.rule_trace             rule_trace
   249 
   250   Thy_Output.display            thy_output_display
   251   Thy_Output.quotes             thy_output_quotes
   252   Thy_Output.indent             thy_output_indent
   253   Thy_Output.source             thy_output_source
   254   Thy_Output.break              thy_output_break
   255 
   256 Note that corresponding "..._default" references in ML may only be
   257 changed globally at the ROOT session setup, but *not* within a theory.
   258 The option "show_abbrevs" supersedes the former print mode
   259 "no_abbrevs" with inverted meaning.
   260 
   261 * More systematic naming of some configuration options.
   262 INCOMPATIBILITY.
   263 
   264   trace_simp  ~>  simp_trace
   265   debug_simp  ~>  simp_debug
   266 
   267 * Support for real valued configuration options, using simplistic
   268 floating-point notation that coincides with the inner syntax for
   269 float_token.
   270 
   271 * Support for real valued preferences (with approximative PGIP type):
   272 front-ends need to accept "pgint" values in float notation.
   273 INCOMPATIBILITY.
   274 
   275 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
   276 DejaVu Sans.
   277 
   278 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   279 
   280 
   281 *** Pure ***
   282 
   283 * Command 'type_synonym' (with single argument) replaces somewhat
   284 outdated 'types', which is still available as legacy feature for some
   285 time.
   286 
   287 * Command 'nonterminal' (with 'and' separated list of arguments)
   288 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
   289 
   290 * Command 'notepad' replaces former 'example_proof' for
   291 experimentation in Isar without any result.  INCOMPATIBILITY.
   292 
   293 * Locale interpretation commands 'interpret' and 'sublocale' accept
   294 lists of equations to map definitions in a locale to appropriate
   295 entities in the context of the interpretation.  The 'interpretation'
   296 command already provided this functionality.
   297 
   298 * Diagnostic command 'print_dependencies' prints the locale instances
   299 that would be activated if the specified expression was interpreted in
   300 the current context.  Variant "print_dependencies!" assumes a context
   301 without interpretations.
   302 
   303 * Diagnostic command 'print_interps' prints interpretations in proofs
   304 in addition to interpretations in theories.
   305 
   306 * Discontinued obsolete 'global' and 'local' commands to manipulate
   307 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
   308 Sign.root_path and Sign.local_path may be applied directly where this
   309 feature is still required for historical reasons.
   310 
   311 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
   312 'definition' instead.
   313 
   314 * The "prems" fact, which refers to the accidental collection of
   315 foundational premises in the context, is now explicitly marked as
   316 legacy feature and will be discontinued soon.  Consider using "assms"
   317 of the head statement or reference facts by explicit names.
   318 
   319 * Document antiquotations @{class} and @{type} print classes and type
   320 constructors.
   321 
   322 * Document antiquotation @{file} checks file/directory entries within
   323 the local file system.
   324 
   325 
   326 *** HOL ***
   327 
   328 * Coercive subtyping: functions can be declared as coercions and type
   329 inference will add them as necessary upon input of a term.  Theory
   330 Complex_Main declares real :: nat => real and real :: int => real as
   331 coercions. A coercion function f is declared like this:
   332 
   333   declare [[coercion f]]
   334 
   335 To lift coercions through type constructors (e.g. from nat => real to
   336 nat list => real list), map functions can be declared, e.g.
   337 
   338   declare [[coercion_map map]]
   339 
   340 Currently coercion inference is activated only in theories including
   341 real numbers, i.e. descendants of Complex_Main.  This is controlled by
   342 the configuration option "coercion_enabled", e.g. it can be enabled in
   343 other theories like this:
   344 
   345   declare [[coercion_enabled]]
   346 
   347 * Command 'partial_function' provides basic support for recursive
   348 function definitions over complete partial orders.  Concrete instances
   349 are provided for i) the option type, ii) tail recursion on arbitrary
   350 types, and iii) the heap monad of Imperative_HOL.  See
   351 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
   352 for examples.
   353 
   354 * Function package: f.psimps rules are no longer implicitly declared
   355 as [simp].  INCOMPATIBILITY.
   356 
   357 * Datatype package: theorems generated for executable equality (class
   358 "eq") carry proper names and are treated as default code equations.
   359 
   360 * Inductive package: now offers command 'inductive_simps' to
   361 automatically derive instantiated and simplified equations for
   362 inductive predicates, similar to 'inductive_cases'.
   363 
   364 * Command 'enriched_type' allows to register properties of the
   365 functorial structure of types.
   366 
   367 * Improved infrastructure for term evaluation using code generator
   368 techniques, in particular static evaluation conversions.
   369 
   370 * Code generator: Scala (2.8 or higher) has been added to the target
   371 languages.
   372 
   373 * Code generator: globbing constant expressions "*" and "Theory.*"
   374 have been replaced by the more idiomatic "_" and "Theory._".
   375 INCOMPATIBILITY.
   376 
   377 * Code generator: export_code without explicit file declaration prints
   378 to standard output.  INCOMPATIBILITY.
   379 
   380 * Code generator: do not print function definitions for case
   381 combinators any longer.
   382 
   383 * Code generator: simplification with rules determined with
   384 src/Tools/Code/code_simp.ML and method "code_simp".
   385 
   386 * Code generator for records: more idiomatic representation of record
   387 types.  Warning: records are not covered by ancient SML code
   388 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
   389 rep_datatype declaration helps to succeed then:
   390 
   391   record 'a foo = ...
   392   ...
   393   rep_datatype foo_ext ...
   394 
   395 * Records: logical foundation type for records does not carry a
   396 '_type' suffix any longer (obsolete due to authentic syntax).
   397 INCOMPATIBILITY.
   398 
   399 * Quickcheck now by default uses exhaustive testing instead of random
   400 testing.  Random testing can be invoked by "quickcheck [random]",
   401 exhaustive testing by "quickcheck [exhaustive]".
   402 
   403 * Quickcheck instantiates polymorphic types with small finite
   404 datatypes by default. This enables a simple execution mechanism to
   405 handle quantifiers and function equality over the finite datatypes.
   406 
   407 * Quickcheck random generator has been renamed from "code" to
   408 "random".  INCOMPATIBILITY.
   409 
   410 * Quickcheck now has a configurable time limit which is set to 30
   411 seconds by default. This can be changed by adding [timeout = n] to the
   412 quickcheck command. The time limit for Auto Quickcheck is still set
   413 independently.
   414 
   415 * Quickcheck in locales considers interpretations of that locale for
   416 counter example search.
   417 
   418 * Sledgehammer:
   419   - Added "smt" and "remote_smt" provers based on the "smt" proof
   420     method. See the Sledgehammer manual for details ("isabelle doc
   421     sledgehammer").
   422   - Renamed commands:
   423     sledgehammer atp_info ~> sledgehammer running_provers
   424     sledgehammer atp_kill ~> sledgehammer kill_provers
   425     sledgehammer available_atps ~> sledgehammer available_provers
   426     INCOMPATIBILITY.
   427   - Renamed options:
   428     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
   429     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
   430     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
   431     (and "ms" and "min" are no longer supported)
   432     INCOMPATIBILITY.
   433 
   434 * Nitpick:
   435   - Renamed options:
   436     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
   437     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
   438     INCOMPATIBILITY.
   439   - Added support for partial quotient types.
   440   - Added local versions of the "Nitpick.register_xxx" functions.
   441   - Added "whack" option.
   442   - Allow registration of quotient types as codatatypes.
   443   - Improved "merge_type_vars" option to merge more types.
   444   - Removed unsound "fast_descrs" option.
   445   - Added custom symmetry breaking for datatypes, making it possible to reach
   446     higher cardinalities.
   447   - Prevent the expansion of too large definitions.
   448 
   449 * Proof methods "metis" and "meson" now have configuration options
   450 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
   451 to diagnose these tools. E.g.
   452 
   453     using [[metis_trace = true]]
   454 
   455 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
   456 manually as command 'solve_direct'.
   457 
   458 * The default SMT solver Z3 must be enabled explicitly (due to
   459 licensing issues) by setting the environment variable
   460 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
   461 commercial applications, the SMT solver CVC3 is provided as fall-back;
   462 changing the SMT solver is done via the configuration option
   463 "smt_solver".
   464 
   465 * Remote SMT solvers need to be referred to by the "remote_" prefix,
   466 i.e. "remote_cvc3" and "remote_z3".
   467 
   468 * Added basic SMT support for datatypes, records, and typedefs using
   469 the oracle mode (no proofs).  Direct support of pairs has been dropped
   470 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
   471 support for a similar behavior).  Minor INCOMPATIBILITY.
   472 
   473 * Changed SMT configuration options:
   474   - Renamed:
   475     z3_proofs ~> smt_oracle (with inverted meaning)
   476     z3_trace_assms ~> smt_trace_used_facts
   477     INCOMPATIBILITY.
   478   - Added:
   479     smt_verbose
   480     smt_random_seed
   481     smt_datatypes
   482     smt_infer_triggers
   483     smt_monomorph_limit
   484     cvc3_options
   485     remote_cvc3_options
   486     remote_z3_options
   487     yices_options
   488 
   489 * Boogie output files (.b2i files) need to be declared in the theory
   490 header.
   491 
   492 * Simplification procedure "list_to_set_comprehension" rewrites list
   493 comprehensions applied to List.set to set comprehensions.  Occasional
   494 INCOMPATIBILITY, may be deactivated like this:
   495 
   496   declare [[simproc del: list_to_set_comprehension]]
   497 
   498 * Removed old version of primrec package.  INCOMPATIBILITY.
   499 
   500 * Removed simplifier congruence rule of "prod_case", as has for long
   501 been the case with "split".  INCOMPATIBILITY.
   502 
   503 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
   504 
   505 * Removed [split_format ... and ... and ...] version of
   506 [split_format].  Potential INCOMPATIBILITY.
   507 
   508 * Predicate "sorted" now defined inductively, with nice induction
   509 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
   510 
   511 * Constant "contents" renamed to "the_elem", to free the generic name
   512 contents for other uses.  INCOMPATIBILITY.
   513 
   514 * Renamed class eq and constant eq (for code generation) to class
   515 equal and constant equal, plus renaming of related facts and various
   516 tuning.  INCOMPATIBILITY.
   517 
   518 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
   519 
   520 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
   521 INCOMPATIBILITY.
   522 
   523 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
   524 avoid confusion with finite sets.  INCOMPATIBILITY.
   525 
   526 * Abandoned locales equiv, congruent and congruent2 for equivalence
   527 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
   528 for congruent(2)).
   529 
   530 * Some previously unqualified names have been qualified:
   531 
   532   types
   533     bool ~> HOL.bool
   534     nat ~> Nat.nat
   535 
   536   constants
   537     Trueprop ~> HOL.Trueprop
   538     True ~> HOL.True
   539     False ~> HOL.False
   540     op & ~> HOL.conj
   541     op | ~> HOL.disj
   542     op --> ~> HOL.implies
   543     op = ~> HOL.eq
   544     Not ~> HOL.Not
   545     The ~> HOL.The
   546     All ~> HOL.All
   547     Ex ~> HOL.Ex
   548     Ex1 ~> HOL.Ex1
   549     Let ~> HOL.Let
   550     If ~> HOL.If
   551     Ball ~> Set.Ball
   552     Bex ~> Set.Bex
   553     Suc ~> Nat.Suc
   554     Pair ~> Product_Type.Pair
   555     fst ~> Product_Type.fst
   556     snd ~> Product_Type.snd
   557     curry ~> Product_Type.curry
   558     op : ~> Set.member
   559     Collect ~> Set.Collect
   560 
   561 INCOMPATIBILITY.
   562 
   563 * More canonical naming convention for some fundamental definitions:
   564 
   565     bot_bool_eq ~> bot_bool_def
   566     top_bool_eq ~> top_bool_def
   567     inf_bool_eq ~> inf_bool_def
   568     sup_bool_eq ~> sup_bool_def
   569     bot_fun_eq  ~> bot_fun_def
   570     top_fun_eq  ~> top_fun_def
   571     inf_fun_eq  ~> inf_fun_def
   572     sup_fun_eq  ~> sup_fun_def
   573 
   574 INCOMPATIBILITY.
   575 
   576 * More stylized fact names:
   577 
   578   expand_fun_eq ~> fun_eq_iff
   579   expand_set_eq ~> set_eq_iff
   580   set_ext       ~> set_eqI
   581   nat_number    ~> eval_nat_numeral
   582 
   583 INCOMPATIBILITY.
   584 
   585 * Refactoring of code-generation specific operations in theory List:
   586 
   587   constants
   588     null ~> List.null
   589 
   590   facts
   591     mem_iff ~> member_def
   592     null_empty ~> null_def
   593 
   594 INCOMPATIBILITY.  Note that these were not supposed to be used
   595 regularly unless for striking reasons; their main purpose was code
   596 generation.
   597 
   598 Various operations from the Haskell prelude are used for generating
   599 Haskell code.
   600 
   601 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
   602 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
   603 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
   604 
   605 * Abolished some non-alphabetic type names: "prod" and "sum" replace
   606 "*" and "+" respectively.  INCOMPATIBILITY.
   607 
   608 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
   609 "Sum_Type.Plus" instead.
   610 
   611 * Constant "split" has been merged with constant "prod_case"; names of
   612 ML functions, facts etc. involving split have been retained so far,
   613 though.  INCOMPATIBILITY.
   614 
   615 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
   616 instead.  INCOMPATIBILITY.
   617 
   618 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
   619 INCOMPATIBILITY.
   620 
   621 * Former theory Library/Enum is now part of the HOL-Main image.
   622 INCOMPATIBILITY: all constants of the Enum theory now have to be
   623 referred to by its qualified name.
   624 
   625   enum    ~>  Enum.enum
   626   nlists  ~>  Enum.nlists
   627   product ~>  Enum.product
   628 
   629 * Theory Library/Monad_Syntax provides do-syntax for monad types.
   630 Syntax in Library/State_Monad has been changed to avoid ambiguities.
   631 INCOMPATIBILITY.
   632 
   633 * Theory Library/SetsAndFunctions has been split into
   634 Library/Function_Algebras and Library/Set_Algebras; canonical names
   635 for instance definitions for functions; various improvements.
   636 INCOMPATIBILITY.
   637 
   638 * Theory Library/Multiset provides stable quicksort implementation of
   639 sort_key.
   640 
   641 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
   642 INCOMPATIBILITY.
   643 
   644 * Session Multivariate_Analysis: introduced a type class for euclidean
   645 space.  Most theorems are now stated in terms of euclidean spaces
   646 instead of finite cartesian products.
   647 
   648   types
   649     real ^ 'n ~>  'a::real_vector
   650               ~>  'a::euclidean_space
   651               ~>  'a::ordered_euclidean_space
   652         (depends on your needs)
   653 
   654   constants
   655      _ $ _        ~> _ $$ _
   656      \<chi> x. _  ~> \<chi>\<chi> x. _
   657      CARD('n)     ~> DIM('a)
   658 
   659 Also note that the indices are now natural numbers and not from some
   660 finite type. Finite cartesian products of euclidean spaces, products
   661 of euclidean spaces the real and complex numbers are instantiated to
   662 be euclidean_spaces.  INCOMPATIBILITY.
   663 
   664 * Session Probability: introduced pextreal as positive extended real
   665 numbers.  Use pextreal as value for measures.  Introduce the
   666 Radon-Nikodym derivative, product spaces and Fubini's theorem for
   667 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
   668 the integral in Multivariate Analysis.  INCOMPATIBILITY.
   669 
   670 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   671 INCOMPATIBILITY.
   672 
   673 * Session SPARK (with image HOL-SPARK) provides commands to load and
   674 prove verification conditions generated by the SPARK Ada program
   675 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
   676 
   677 
   678 *** HOL-Algebra ***
   679 
   680 * Theorems for additive ring operations (locale abelian_monoid and
   681 descendants) are generated by interpretation from their multiplicative
   682 counterparts.  Names (in particular theorem names) have the mandatory
   683 qualifier 'add'.  Previous theorem names are redeclared for
   684 compatibility.
   685 
   686 * Structure "int_ring" is now an abbreviation (previously a
   687 definition).  This fits more natural with advanced interpretations.
   688 
   689 
   690 *** HOLCF ***
   691 
   692 * The domain package now runs in definitional mode by default: The
   693 former command 'new_domain' is now called 'domain'.  To use the domain
   694 package in its original axiomatic mode, use 'domain (unsafe)'.
   695 INCOMPATIBILITY.
   696 
   697 * The new class "domain" is now the default sort.  Class "predomain"
   698 is an unpointed version of "domain". Theories can be updated by
   699 replacing sort annotations as shown below.  INCOMPATIBILITY.
   700 
   701   'a::type ~> 'a::countable
   702   'a::cpo  ~> 'a::predomain
   703   'a::pcpo ~> 'a::domain
   704 
   705 * The old type class "rep" has been superseded by class "domain".
   706 Accordingly, users of the definitional package must remove any
   707 "default_sort rep" declarations.  INCOMPATIBILITY.
   708 
   709 * The domain package (definitional mode) now supports unpointed
   710 predomain argument types, as long as they are marked 'lazy'. (Strict
   711 arguments must be in class "domain".) For example, the following
   712 domain definition now works:
   713 
   714   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
   715 
   716 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
   717 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
   718 'a option, and 'a list.  Additionally, it configures fixrec and the
   719 domain package to work with these types.  For example:
   720 
   721   fixrec isInl :: "('a + 'b) u -> tr"
   722     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
   723 
   724   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
   725 
   726 * The "(permissive)" option of fixrec has been replaced with a
   727 per-equation "(unchecked)" option. See
   728 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
   729 
   730 * The "bifinite" class no longer fixes a constant "approx"; the class
   731 now just asserts that such a function exists.  INCOMPATIBILITY.
   732 
   733 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
   734 defines an embedding of type 'a defl into udom by default; instances
   735 of "bifinite" and "domain" classes are available in
   736 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
   737 
   738 * The syntax "REP('a)" has been replaced with "DEFL('a)".
   739 
   740 * The predicate "directed" has been removed.  INCOMPATIBILITY.
   741 
   742 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
   743 
   744 * The function "cprod_map" has been renamed to "prod_map".
   745 INCOMPATIBILITY.
   746 
   747 * The monadic bind operator on each powerdomain has new binder syntax
   748 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
   749 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
   750 
   751 * The infix syntax for binary union on each powerdomain has changed
   752 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
   753 syntax.  INCOMPATIBILITY.
   754 
   755 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
   756 still supported as an input translation.
   757 
   758 * Renamed some theorems (the original names are also still available).
   759 
   760   expand_fun_below   ~> fun_below_iff
   761   below_fun_ext      ~> fun_belowI
   762   expand_cfun_eq     ~> cfun_eq_iff
   763   ext_cfun           ~> cfun_eqI
   764   expand_cfun_below  ~> cfun_below_iff
   765   below_cfun_ext     ~> cfun_belowI
   766   cont2cont_Rep_CFun ~> cont2cont_APP
   767 
   768 * The Abs and Rep functions for various types have changed names.
   769 Related theorem names have also changed to match. INCOMPATIBILITY.
   770 
   771   Rep_CFun  ~> Rep_cfun
   772   Abs_CFun  ~> Abs_cfun
   773   Rep_Sprod ~> Rep_sprod
   774   Abs_Sprod ~> Abs_sprod
   775   Rep_Ssum  ~> Rep_ssum
   776   Abs_Ssum  ~> Abs_ssum
   777 
   778 * Lemmas with names of the form *_defined_iff or *_strict_iff have
   779 been renamed to *_bottom_iff.  INCOMPATIBILITY.
   780 
   781 * Various changes to bisimulation/coinduction with domain package:
   782 
   783   - Definitions of "bisim" constants no longer mention definedness.
   784   - With mutual recursion, "bisim" predicate is now curried.
   785   - With mutual recursion, each type gets a separate coind theorem.
   786   - Variable names in bisim_def and coinduct rules have changed.
   787 
   788 INCOMPATIBILITY.
   789 
   790 * Case combinators generated by the domain package for type "foo" are
   791 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
   792 
   793 * Several theorems have been renamed to more accurately reflect the
   794 names of constants and types involved.  INCOMPATIBILITY.
   795 
   796   thelub_const    ~> lub_const
   797   lub_const       ~> is_lub_const
   798   thelubI         ~> lub_eqI
   799   is_lub_lub      ~> is_lubD2
   800   lubI            ~> is_lub_lub
   801   unique_lub      ~> is_lub_unique
   802   is_ub_lub       ~> is_lub_rangeD1
   803   lub_bin_chain   ~> is_lub_bin_chain
   804   lub_fun         ~> is_lub_fun
   805   thelub_fun      ~> lub_fun
   806   thelub_cfun     ~> lub_cfun
   807   thelub_Pair     ~> lub_Pair
   808   lub_cprod       ~> is_lub_prod
   809   thelub_cprod    ~> lub_prod
   810   minimal_cprod   ~> minimal_prod
   811   inst_cprod_pcpo ~> inst_prod_pcpo
   812   UU_I            ~> bottomI
   813   compact_UU      ~> compact_bottom
   814   deflation_UU    ~> deflation_bottom
   815   finite_deflation_UU ~> finite_deflation_bottom
   816 
   817 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
   818 
   819   sq_ord_less_eq_trans ~> below_eq_trans
   820   sq_ord_eq_less_trans ~> eq_below_trans
   821   refl_less            ~> below_refl
   822   trans_less           ~> below_trans
   823   antisym_less         ~> below_antisym
   824   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
   825   box_less             ~> box_below
   826   rev_trans_less       ~> rev_below_trans
   827   not_less2not_eq      ~> not_below2not_eq
   828   less_UU_iff          ~> below_UU_iff
   829   flat_less_iff        ~> flat_below_iff
   830   adm_less             ~> adm_below
   831   adm_not_less         ~> adm_not_below
   832   adm_compact_not_less ~> adm_compact_not_below
   833   less_fun_def         ~> below_fun_def
   834   expand_fun_less      ~> fun_below_iff
   835   less_fun_ext         ~> fun_belowI
   836   less_discr_def       ~> below_discr_def
   837   discr_less_eq        ~> discr_below_eq
   838   less_unit_def        ~> below_unit_def
   839   less_cprod_def       ~> below_prod_def
   840   prod_lessI           ~> prod_belowI
   841   Pair_less_iff        ~> Pair_below_iff
   842   fst_less_iff         ~> fst_below_iff
   843   snd_less_iff         ~> snd_below_iff
   844   expand_cfun_less     ~> cfun_below_iff
   845   less_cfun_ext        ~> cfun_belowI
   846   injection_less       ~> injection_below
   847   less_up_def          ~> below_up_def
   848   not_Iup_less         ~> not_Iup_below
   849   Iup_less             ~> Iup_below
   850   up_less              ~> up_below
   851   Def_inject_less_eq   ~> Def_below_Def
   852   Def_less_is_eq       ~> Def_below_iff
   853   spair_less_iff       ~> spair_below_iff
   854   less_sprod           ~> below_sprod
   855   spair_less           ~> spair_below
   856   sfst_less_iff        ~> sfst_below_iff
   857   ssnd_less_iff        ~> ssnd_below_iff
   858   fix_least_less       ~> fix_least_below
   859   dist_less_one        ~> dist_below_one
   860   less_ONE             ~> below_ONE
   861   ONE_less_iff         ~> ONE_below_iff
   862   less_sinlD           ~> below_sinlD
   863   less_sinrD           ~> below_sinrD
   864 
   865 
   866 *** FOL and ZF ***
   867 
   868 * All constant names are now qualified internally and use proper
   869 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
   870 
   871 
   872 *** ML ***
   873 
   874 * Antiquotation @{assert} inlines a function bool -> unit that raises
   875 Fail if the argument is false.  Due to inlining the source position of
   876 failed assertions is included in the error output.
   877 
   878 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
   879 text is in practice always evaluated with a stable theory checkpoint.
   880 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
   881 
   882 * Antiquotation @{theory A} refers to theory A from the ancestry of
   883 the current context, not any accidental theory loader state as before.
   884 Potential INCOMPATIBILITY, subtle change in semantics.
   885 
   886 * Syntax.pretty_priority (default 0) configures the required priority
   887 of pretty-printed output and thus affects insertion of parentheses.
   888 
   889 * Syntax.default_root (default "any") configures the inner syntax
   890 category (nonterminal symbol) for parsing of terms.
   891 
   892 * Former exception Library.UnequalLengths now coincides with
   893 ListPair.UnequalLengths.
   894 
   895 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
   896 main functionality is provided by structure Simplifier.
   897 
   898 * Renamed raw "explode" function to "raw_explode" to emphasize its
   899 meaning.  Note that internally to Isabelle, Symbol.explode is used in
   900 almost all situations.
   901 
   902 * Discontinued obsolete function sys_error and exception SYS_ERROR.
   903 See implementation manual for further details on exceptions in
   904 Isabelle/ML.
   905 
   906 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
   907 meaning.
   908 
   909 * Renamed structure PureThy to Pure_Thy and moved most of its
   910 operations to structure Global_Theory, to emphasize that this is
   911 rarely-used global-only stuff.
   912 
   913 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
   914 instead (or tracing for high-volume output).
   915 
   916 * Configuration option show_question_marks only affects regular pretty
   917 printing of types and terms, not raw Term.string_of_vname.
   918 
   919 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
   920 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
   921 @{thms} for most purposes.
   922 
   923 * ML structure Unsynchronized is never opened, not even in Isar
   924 interaction mode as before.  Old Unsynchronized.set etc. have been
   925 discontinued -- use plain := instead.  This should be *rare* anyway,
   926 since modern tools always work via official context data, notably
   927 configuration options.
   928 
   929 * Parallel and asynchronous execution requires special care concerning
   930 interrupts.  Structure Exn provides some convenience functions that
   931 avoid working directly with raw Interrupt.  User code must not absorb
   932 interrupts -- intermediate handling (for cleanup etc.) needs to be
   933 followed by re-raising of the original exception.  Another common
   934 source of mistakes are "handle _" patterns, which make the meaning of
   935 the program subject to physical effects of the environment.
   936 
   937 
   938 
   939 New in Isabelle2009-2 (June 2010)
   940 ---------------------------------
   941 
   942 *** General ***
   943 
   944 * Authentic syntax for *all* logical entities (type classes, type
   945 constructors, term constants): provides simple and robust
   946 correspondence between formal entities and concrete syntax.  Within
   947 the parse tree / AST representations, "constants" are decorated by
   948 their category (class, type, const) and spelled out explicitly with
   949 their full internal name.
   950 
   951 Substantial INCOMPATIBILITY concerning low-level syntax declarations
   952 and translations (translation rules and translation functions in ML).
   953 Some hints on upgrading:
   954 
   955   - Many existing uses of 'syntax' and 'translations' can be replaced
   956     by more modern 'type_notation', 'notation' and 'abbreviation',
   957     which are independent of this issue.
   958 
   959   - 'translations' require markup within the AST; the term syntax
   960     provides the following special forms:
   961 
   962       CONST c   -- produces syntax version of constant c from context
   963       XCONST c  -- literally c, checked as constant from context
   964       c         -- literally c, if declared by 'syntax'
   965 
   966     Plain identifiers are treated as AST variables -- occasionally the
   967     system indicates accidental variables via the error "rhs contains
   968     extra variables".
   969 
   970     Type classes and type constructors are marked according to their
   971     concrete syntax.  Some old translations rules need to be written
   972     for the "type" category, using type constructor application
   973     instead of pseudo-term application of the default category
   974     "logic".
   975 
   976   - 'parse_translation' etc. in ML may use the following
   977     antiquotations:
   978 
   979       @{class_syntax c}   -- type class c within parse tree / AST
   980       @{term_syntax c}    -- type constructor c within parse tree / AST
   981       @{const_syntax c}   -- ML version of "CONST c" above
   982       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
   983 
   984   - Literal types within 'typed_print_translations', i.e. those *not*
   985     represented as pseudo-terms are represented verbatim.  Use @{class
   986     c} or @{type_name c} here instead of the above syntax
   987     antiquotations.
   988 
   989 Note that old non-authentic syntax was based on unqualified base
   990 names, so all of the above "constant" names would coincide.  Recall
   991 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
   992 diagnose syntax problems.
   993 
   994 * Type constructors admit general mixfix syntax, not just infix.
   995 
   996 * Concrete syntax may be attached to local entities without a proof
   997 body, too.  This works via regular mixfix annotations for 'fix',
   998 'def', 'obtain' etc. or via the explicit 'write' command, which is
   999 similar to the 'notation' command in theory specifications.
  1000 
  1001 * Discontinued unnamed infix syntax (legacy feature for many years) --
  1002 need to specify constant name and syntax separately.  Internal ML
  1003 datatype constructors have been renamed from InfixName to Infix etc.
  1004 Minor INCOMPATIBILITY.
  1005 
  1006 * Schematic theorem statements need to be explicitly markup as such,
  1007 via commands 'schematic_lemma', 'schematic_theorem',
  1008 'schematic_corollary'.  Thus the relevance of the proof is made
  1009 syntactically clear, which impacts performance in a parallel or
  1010 asynchronous interactive environment.  Minor INCOMPATIBILITY.
  1011 
  1012 * Use of cumulative prems via "!" in some proof methods has been
  1013 discontinued (old legacy feature).
  1014 
  1015 * References 'trace_simp' and 'debug_simp' have been replaced by
  1016 configuration options stored in the context. Enabling tracing (the
  1017 case of debugging is similar) in proofs works via
  1018 
  1019   using [[trace_simp = true]]
  1020 
  1021 Tracing is then active for all invocations of the simplifier in
  1022 subsequent goal refinement steps. Tracing may also still be enabled or
  1023 disabled via the ProofGeneral settings menu.
  1024 
  1025 * Separate commands 'hide_class', 'hide_type', 'hide_const',
  1026 'hide_fact' replace the former 'hide' KIND command.  Minor
  1027 INCOMPATIBILITY.
  1028 
  1029 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
  1030 more efficient than combinations with -q1 or -q2.
  1031 
  1032 
  1033 *** Pure ***
  1034 
  1035 * Proofterms record type-class reasoning explicitly, using the
  1036 "unconstrain" operation internally.  This eliminates all sort
  1037 constraints from a theorem and proof, introducing explicit
  1038 OFCLASS-premises.  On the proof term level, this operation is
  1039 automatically applied at theorem boundaries, such that closed proofs
  1040 are always free of sort constraints.  INCOMPATIBILITY for tools that
  1041 inspect proof terms.
  1042 
  1043 * Local theory specifications may depend on extra type variables that
  1044 are not present in the result type -- arguments TYPE('a) :: 'a itself
  1045 are added internally.  For example:
  1046 
  1047   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
  1048 
  1049 * Predicates of locales introduced by classes carry a mandatory
  1050 "class" prefix.  INCOMPATIBILITY.
  1051 
  1052 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
  1053 
  1054 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
  1055 'class' instead.
  1056 
  1057 * Command 'code_reflect' allows to incorporate generated ML code into
  1058 runtime environment; replaces immature code_datatype antiquotation.
  1059 INCOMPATIBILITY.
  1060 
  1061 * Code generator: simple concept for abstract datatypes obeying
  1062 invariants.
  1063 
  1064 * Code generator: details of internal data cache have no impact on the
  1065 user space functionality any longer.
  1066 
  1067 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  1068 subgoals.  This is more appropriate for interpretations with 'where'.
  1069 INCOMPATIBILITY.
  1070 
  1071 * Command 'example_proof' opens an empty proof body.  This allows to
  1072 experiment with Isar, without producing any persistent result.
  1073 
  1074 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  1075 within a local theory context, with explicit checking of the
  1076 constructors involved (in contrast to the raw 'syntax' versions).
  1077 
  1078 * Commands 'types' and 'typedecl' now work within a local theory
  1079 context -- without introducing dependencies on parameters or
  1080 assumptions, which is not possible in Isabelle/Pure.
  1081 
  1082 * Command 'defaultsort' has been renamed to 'default_sort', it works
  1083 within a local theory context.  Minor INCOMPATIBILITY.
  1084 
  1085 
  1086 *** HOL ***
  1087 
  1088 * Command 'typedef' now works within a local theory context -- without
  1089 introducing dependencies on parameters or assumptions, which is not
  1090 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  1091 contain multiple interpretations of local typedefs (with different
  1092 non-emptiness proofs), even in a global theory context.
  1093 
  1094 * New package for quotient types.  Commands 'quotient_type' and
  1095 'quotient_definition' may be used for defining types and constants by
  1096 quotient constructions.  An example is the type of integers created by
  1097 quotienting pairs of natural numbers:
  1098 
  1099   fun
  1100     intrel :: "(nat * nat) => (nat * nat) => bool"
  1101   where
  1102     "intrel (x, y) (u, v) = (x + v = u + y)"
  1103 
  1104   quotient_type int = "nat * nat" / intrel
  1105     by (auto simp add: equivp_def expand_fun_eq)
  1106 
  1107   quotient_definition
  1108     "0::int" is "(0::nat, 0::nat)"
  1109 
  1110 The method "lifting" can be used to lift of theorems from the
  1111 underlying "raw" type to the quotient type.  The example
  1112 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  1113 construction and provides a reasoning infrastructure for finite sets.
  1114 
  1115 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  1116 clash with new theory Quotient in Main HOL.
  1117 
  1118 * Moved the SMT binding into the main HOL session, eliminating
  1119 separate HOL-SMT session.
  1120 
  1121 * List membership infix mem operation is only an input abbreviation.
  1122 INCOMPATIBILITY.
  1123 
  1124 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  1125 for future developements; former Library/Word.thy is still present in
  1126 the AFP entry RSAPPS.
  1127 
  1128 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  1129 longer shadowed.  INCOMPATIBILITY.
  1130 
  1131 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  1132 INCOMPATIBILITY.
  1133 
  1134 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  1135 INCOMPATIBILITY.
  1136 
  1137 * Dropped normalizing_semiring etc; use the facts in semiring classes
  1138 instead.  INCOMPATIBILITY.
  1139 
  1140 * Dropped several real-specific versions of lemmas about floor and
  1141 ceiling; use the generic lemmas from theory "Archimedean_Field"
  1142 instead.  INCOMPATIBILITY.
  1143 
  1144   floor_number_of_eq         ~> floor_number_of
  1145   le_floor_eq_number_of      ~> number_of_le_floor
  1146   le_floor_eq_zero           ~> zero_le_floor
  1147   le_floor_eq_one            ~> one_le_floor
  1148   floor_less_eq_number_of    ~> floor_less_number_of
  1149   floor_less_eq_zero         ~> floor_less_zero
  1150   floor_less_eq_one          ~> floor_less_one
  1151   less_floor_eq_number_of    ~> number_of_less_floor
  1152   less_floor_eq_zero         ~> zero_less_floor
  1153   less_floor_eq_one          ~> one_less_floor
  1154   floor_le_eq_number_of      ~> floor_le_number_of
  1155   floor_le_eq_zero           ~> floor_le_zero
  1156   floor_le_eq_one            ~> floor_le_one
  1157   floor_subtract_number_of   ~> floor_diff_number_of
  1158   floor_subtract_one         ~> floor_diff_one
  1159   ceiling_number_of_eq       ~> ceiling_number_of
  1160   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  1161   ceiling_le_zero_eq         ~> ceiling_le_zero
  1162   ceiling_le_eq_one          ~> ceiling_le_one
  1163   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  1164   less_ceiling_eq_zero       ~> zero_less_ceiling
  1165   less_ceiling_eq_one        ~> one_less_ceiling
  1166   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  1167   ceiling_less_eq_zero       ~> ceiling_less_zero
  1168   ceiling_less_eq_one        ~> ceiling_less_one
  1169   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  1170   le_ceiling_eq_zero         ~> zero_le_ceiling
  1171   le_ceiling_eq_one          ~> one_le_ceiling
  1172   ceiling_subtract_number_of ~> ceiling_diff_number_of
  1173   ceiling_subtract_one       ~> ceiling_diff_one
  1174 
  1175 * Theory "Finite_Set": various folding_XXX locales facilitate the
  1176 application of the various fold combinators on finite sets.
  1177 
  1178 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  1179 provides abstract red-black tree type which is backed by "RBT_Impl" as
  1180 implementation.  INCOMPATIBILTY.
  1181 
  1182 * Theory Library/Coinductive_List has been removed -- superseded by
  1183 AFP/thys/Coinductive.
  1184 
  1185 * Theory PReal, including the type "preal" and related operations, has
  1186 been removed.  INCOMPATIBILITY.
  1187 
  1188 * Real: new development using Cauchy Sequences.
  1189 
  1190 * Split off theory "Big_Operators" containing setsum, setprod,
  1191 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  1192 
  1193 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  1194 "Int" etc.  INCOMPATIBILITY.
  1195 
  1196 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  1197 
  1198 * New set of rules "ac_simps" provides combined assoc / commute
  1199 rewrites for all interpretations of the appropriate generic locales.
  1200 
  1201 * Renamed theory "OrderedGroup" to "Groups" and split theory
  1202 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  1203 appropriate and more consistent names suitable for name prefixes
  1204 within the HOL theories.  INCOMPATIBILITY.
  1205 
  1206 * Some generic constants have been put to appropriate theories:
  1207   - less_eq, less: Orderings
  1208   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  1209   - inverse, divide: Rings
  1210 INCOMPATIBILITY.
  1211 
  1212 * More consistent naming of type classes involving orderings (and
  1213 lattices):
  1214 
  1215     lower_semilattice                   ~> semilattice_inf
  1216     upper_semilattice                   ~> semilattice_sup
  1217 
  1218     dense_linear_order                  ~> dense_linorder
  1219 
  1220     pordered_ab_group_add               ~> ordered_ab_group_add
  1221     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  1222     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  1223     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  1224     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  1225     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  1226     pordered_cancel_semiring            ~> ordered_cancel_semiring
  1227     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  1228     pordered_comm_ring                  ~> ordered_comm_ring
  1229     pordered_comm_semiring              ~> ordered_comm_semiring
  1230     pordered_ring                       ~> ordered_ring
  1231     pordered_ring_abs                   ~> ordered_ring_abs
  1232     pordered_semiring                   ~> ordered_semiring
  1233 
  1234     ordered_ab_group_add                ~> linordered_ab_group_add
  1235     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  1236     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  1237     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  1238     ordered_field                       ~> linordered_field
  1239     ordered_field_no_lb                 ~> linordered_field_no_lb
  1240     ordered_field_no_ub                 ~> linordered_field_no_ub
  1241     ordered_field_dense_linear_order    ~> dense_linordered_field
  1242     ordered_idom                        ~> linordered_idom
  1243     ordered_ring                        ~> linordered_ring
  1244     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  1245     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  1246     ordered_ring_strict                 ~> linordered_ring_strict
  1247     ordered_semidom                     ~> linordered_semidom
  1248     ordered_semiring                    ~> linordered_semiring
  1249     ordered_semiring_1                  ~> linordered_semiring_1
  1250     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  1251     ordered_semiring_strict             ~> linordered_semiring_strict
  1252 
  1253   The following slightly odd type classes have been moved to a
  1254   separate theory Library/Lattice_Algebras:
  1255 
  1256     lordered_ab_group_add               ~> lattice_ab_group_add
  1257     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  1258     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  1259     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  1260     lordered_ring                       ~> lattice_ring
  1261 
  1262 INCOMPATIBILITY.
  1263 
  1264 * Refined field classes:
  1265   - classes division_ring_inverse_zero, field_inverse_zero,
  1266     linordered_field_inverse_zero include rule inverse 0 = 0 --
  1267     subsumes former division_by_zero class;
  1268   - numerous lemmas have been ported from field to division_ring.
  1269 INCOMPATIBILITY.
  1270 
  1271 * Refined algebra theorem collections:
  1272   - dropped theorem group group_simps, use algebra_simps instead;
  1273   - dropped theorem group ring_simps, use field_simps instead;
  1274   - proper theorem collection field_simps subsumes former theorem
  1275     groups field_eq_simps and field_simps;
  1276   - dropped lemma eq_minus_self_iff which is a duplicate for
  1277     equal_neg_zero.
  1278 INCOMPATIBILITY.
  1279 
  1280 * Theory Finite_Set and List: some lemmas have been generalized from
  1281 sets to lattices:
  1282 
  1283   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  1284   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  1285   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  1286   union_Union_fold_union        ~> sup_Sup_fold_sup
  1287   Inter_fold_inter              ~> Inf_fold_inf
  1288   Union_fold_union              ~> Sup_fold_sup
  1289   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  1290   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  1291   INTER_fold_inter              ~> INFI_fold_inf
  1292   UNION_fold_union              ~> SUPR_fold_sup
  1293 
  1294 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  1295 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  1296 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  1297 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  1298 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  1299 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  1300 
  1301 * Reorganized theory Multiset: swapped notation of pointwise and
  1302 multiset order:
  1303 
  1304   - pointwise ordering is instance of class order with standard syntax
  1305     <= and <;
  1306   - multiset ordering has syntax <=# and <#; partial order properties
  1307     are provided by means of interpretation with prefix
  1308     multiset_order;
  1309   - less duplication, less historical organization of sections,
  1310     conversion from associations lists to multisets, rudimentary code
  1311     generation;
  1312   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  1313     if needed.
  1314 
  1315 Renamed:
  1316 
  1317   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  1318   multi_count_ext  ~>  multiset_ext
  1319   diff_union_inverse2  ~>  diff_union_cancelR
  1320 
  1321 INCOMPATIBILITY.
  1322 
  1323 * Theory Permutation: replaced local "remove" by List.remove1.
  1324 
  1325 * Code generation: ML and OCaml code is decorated with signatures.
  1326 
  1327 * Theory List: added transpose.
  1328 
  1329 * Library/Nat_Bijection.thy is a collection of bijective functions
  1330 between nat and other types, which supersedes the older libraries
  1331 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  1332 
  1333   Constants:
  1334   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  1335   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  1336   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  1337   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  1338   Countable.pair_encode           ~> prod_encode
  1339   NatIso.prod2nat                 ~> prod_encode
  1340   NatIso.nat2prod                 ~> prod_decode
  1341   NatIso.sum2nat                  ~> sum_encode
  1342   NatIso.nat2sum                  ~> sum_decode
  1343   NatIso.list2nat                 ~> list_encode
  1344   NatIso.nat2list                 ~> list_decode
  1345   NatIso.set2nat                  ~> set_encode
  1346   NatIso.nat2set                  ~> set_decode
  1347 
  1348   Lemmas:
  1349   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  1350   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  1351   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  1352   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  1353   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  1354   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  1355   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  1356   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  1357   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  1358   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  1359   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  1360   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  1361   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  1362 
  1363 * Sledgehammer:
  1364   - Renamed ATP commands:
  1365     atp_info     ~> sledgehammer running_atps
  1366     atp_kill     ~> sledgehammer kill_atps
  1367     atp_messages ~> sledgehammer messages
  1368     atp_minimize ~> sledgehammer minimize
  1369     print_atps   ~> sledgehammer available_atps
  1370     INCOMPATIBILITY.
  1371   - Added user's manual ("isabelle doc sledgehammer").
  1372   - Added option syntax and "sledgehammer_params" to customize
  1373     Sledgehammer's behavior.  See the manual for details.
  1374   - Modified the Isar proof reconstruction code so that it produces
  1375     direct proofs rather than proofs by contradiction.  (This feature
  1376     is still experimental.)
  1377   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  1378     full-typed mode.
  1379   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  1380 
  1381 * Nitpick:
  1382   - Added and implemented "binary_ints" and "bits" options.
  1383   - Added "std" option and implemented support for nonstandard models.
  1384   - Added and implemented "finitize" option to improve the precision
  1385     of infinite datatypes based on a monotonicity analysis.
  1386   - Added support for quotient types.
  1387   - Added support for "specification" and "ax_specification"
  1388     constructs.
  1389   - Added support for local definitions (for "function" and
  1390     "termination" proofs).
  1391   - Added support for term postprocessors.
  1392   - Optimized "Multiset.multiset" and "FinFun.finfun".
  1393   - Improved efficiency of "destroy_constrs" optimization.
  1394   - Fixed soundness bugs related to "destroy_constrs" optimization and
  1395     record getters.
  1396   - Fixed soundness bug related to higher-order constructors.
  1397   - Fixed soundness bug when "full_descrs" is enabled.
  1398   - Improved precision of set constructs.
  1399   - Added "atoms" option.
  1400   - Added cache to speed up repeated Kodkod invocations on the same
  1401     problems.
  1402   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  1403     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  1404     "SAT4J_Light".  INCOMPATIBILITY.
  1405   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  1406     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  1407   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  1408 
  1409 * Method "induct" now takes instantiations of the form t, where t is not
  1410   a variable, as a shorthand for "x == t", where x is a fresh variable.
  1411   If this is not intended, t has to be enclosed in parentheses.
  1412   By default, the equalities generated by definitional instantiations
  1413   are pre-simplified, which may cause parameters of inductive cases
  1414   to disappear, or may even delete some of the inductive cases.
  1415   Use "induct (no_simp)" instead of "induct" to restore the old
  1416   behaviour. The (no_simp) option is also understood by the "cases"
  1417   and "nominal_induct" methods, which now perform pre-simplification, too.
  1418   INCOMPATIBILITY.
  1419 
  1420 
  1421 *** HOLCF ***
  1422 
  1423 * Variable names in lemmas generated by the domain package have
  1424 changed; the naming scheme is now consistent with the HOL datatype
  1425 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  1426 
  1427 * The domain package no longer defines the function "foo_copy" for
  1428 recursive domain "foo".  The reach lemma is now stated directly in
  1429 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  1430 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  1431 
  1432 * Most definedness lemmas generated by the domain package (previously
  1433 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  1434 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  1435 Proofs that used definedness lemmas as intro rules may break,
  1436 potential INCOMPATIBILITY.
  1437 
  1438 * Induction and casedist rules generated by the domain package now
  1439 declare proper case_names (one called "bottom", and one named for each
  1440 constructor).  INCOMPATIBILITY.
  1441 
  1442 * For mutually-recursive domains, separate "reach" and "take_lemma"
  1443 rules are generated for each domain, INCOMPATIBILITY.
  1444 
  1445   foo_bar.reach       ~> foo.reach  bar.reach
  1446   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  1447 
  1448 * Some lemmas generated by the domain package have been renamed for
  1449 consistency with the datatype package, INCOMPATIBILITY.
  1450 
  1451   foo.ind        ~> foo.induct
  1452   foo.finite_ind ~> foo.finite_induct
  1453   foo.coind      ~> foo.coinduct
  1454   foo.casedist   ~> foo.exhaust
  1455   foo.exhaust    ~> foo.nchotomy
  1456 
  1457 * For consistency with other definition packages, the fixrec package
  1458 now generates qualified theorem names, INCOMPATIBILITY.
  1459 
  1460   foo_simps  ~> foo.simps
  1461   foo_unfold ~> foo.unfold
  1462   foo_induct ~> foo.induct
  1463 
  1464 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  1465 method and internal fixrec proofs now use the default simpset instead.
  1466 INCOMPATIBILITY.
  1467 
  1468 * The "contlub" predicate has been removed.  Proof scripts should use
  1469 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  1470 
  1471 * The "admw" predicate has been removed, INCOMPATIBILITY.
  1472 
  1473 * The constants cpair, cfst, and csnd have been removed in favor of
  1474 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  1475 
  1476 
  1477 *** ML ***
  1478 
  1479 * Antiquotations for basic formal entities:
  1480 
  1481     @{class NAME}         -- type class
  1482     @{class_syntax NAME}  -- syntax representation of the above
  1483 
  1484     @{type_name NAME}     -- logical type
  1485     @{type_abbrev NAME}   -- type abbreviation
  1486     @{nonterminal NAME}   -- type of concrete syntactic category
  1487     @{type_syntax NAME}   -- syntax representation of any of the above
  1488 
  1489     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  1490     @{const_abbrev NAME}  -- abbreviated constant
  1491     @{const_syntax NAME}  -- syntax representation of any of the above
  1492 
  1493 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  1494 syntax constant (cf. 'syntax' command).
  1495 
  1496 * Antiquotation @{make_string} inlines a function to print arbitrary
  1497 values similar to the ML toplevel.  The result is compiler dependent
  1498 and may fall back on "?" in certain situations.
  1499 
  1500 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  1501 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  1502 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  1503 not work with the asynchronous Isar document model.
  1504 
  1505 * Configuration options now admit dynamic default values, depending on
  1506 the context or even global references.
  1507 
  1508 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  1509 uses an efficient external library if available (for Poly/ML).
  1510 
  1511 * Renamed some important ML structures, while keeping the old names
  1512 for some time as aliases within the structure Legacy:
  1513 
  1514   OuterKeyword  ~>  Keyword
  1515   OuterLex      ~>  Token
  1516   OuterParse    ~>  Parse
  1517   OuterSyntax   ~>  Outer_Syntax
  1518   PrintMode     ~>  Print_Mode
  1519   SpecParse     ~>  Parse_Spec
  1520   ThyInfo       ~>  Thy_Info
  1521   ThyLoad       ~>  Thy_Load
  1522   ThyOutput     ~>  Thy_Output
  1523   TypeInfer     ~>  Type_Infer
  1524 
  1525 Note that "open Legacy" simplifies porting of sources, but forgetting
  1526 to remove it again will complicate porting again in the future.
  1527 
  1528 * Most operations that refer to a global context are named
  1529 accordingly, e.g. Simplifier.global_context or
  1530 ProofContext.init_global.  There are some situations where a global
  1531 context actually works, but under normal circumstances one needs to
  1532 pass the proper local context through the code!
  1533 
  1534 * Discontinued old TheoryDataFun with its copy/init operation -- data
  1535 needs to be pure.  Functor Theory_Data_PP retains the traditional
  1536 Pretty.pp argument to merge, which is absent in the standard
  1537 Theory_Data version.
  1538 
  1539 * Sorts.certify_sort and derived "cert" operations for types and terms
  1540 no longer minimize sorts.  Thus certification at the boundary of the
  1541 inference kernel becomes invariant under addition of class relations,
  1542 which is an important monotonicity principle.  Sorts are now minimized
  1543 in the syntax layer only, at the boundary between the end-user and the
  1544 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  1545 explicitly in rare situations.
  1546 
  1547 * Renamed old-style Drule.standard to Drule.export_without_context, to
  1548 emphasize that this is in no way a standard operation.
  1549 INCOMPATIBILITY.
  1550 
  1551 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  1552 usual for resolution.  Rare INCOMPATIBILITY.
  1553 
  1554 * Renamed varify/unvarify operations to varify_global/unvarify_global
  1555 to emphasize that these only work in a global situation (which is
  1556 quite rare).
  1557 
  1558 * Curried take and drop in library.ML; negative length is interpreted
  1559 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  1560 
  1561 * Proof terms: type substitutions on proof constants now use canonical
  1562 order of type variables.  INCOMPATIBILITY for tools working with proof
  1563 terms.
  1564 
  1565 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  1566 may no longer carry premises.  User-level specifications are
  1567 transformed accordingly by Thm.add_axiom/add_def.
  1568 
  1569 
  1570 *** System ***
  1571 
  1572 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  1573 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  1574 proof terms are enabled unconditionally in the new HOL-Proofs image.
  1575 
  1576 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  1577 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  1578 respectively.
  1579 
  1580 * Old lib/scripts/polyml-platform is superseded by the
  1581 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  1582 variant, even on a 64 bit machine.  The following example setting
  1583 prefers 64 bit if available:
  1584 
  1585   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  1586 
  1587 * The preliminary Isabelle/jEdit application demonstrates the emerging
  1588 Isabelle/Scala layer for advanced prover interaction and integration.
  1589 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  1590 component.
  1591 
  1592 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  1593 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  1594 similar to the default assignment of the document preparation system
  1595 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  1596 provides some operations for direct access to the font without asking
  1597 the user for manual installation.
  1598 
  1599 
  1600 
  1601 New in Isabelle2009-1 (December 2009)
  1602 -------------------------------------
  1603 
  1604 *** General ***
  1605 
  1606 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  1607 one backslash should be used, even in ML sources.
  1608 
  1609 
  1610 *** Pure ***
  1611 
  1612 * Locale interpretation propagates mixins along the locale hierarchy.
  1613 The currently only available mixins are the equations used to map
  1614 local definitions to terms of the target domain of an interpretation.
  1615 
  1616 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  1617 loc" to print all interpretations of locale "loc" in the theory.
  1618 Interpretations in proofs are not shown.
  1619 
  1620 * Thoroughly revised locales tutorial.  New section on conditional
  1621 interpretation.
  1622 
  1623 * On instantiation of classes, remaining undefined class parameters
  1624 are formally declared.  INCOMPATIBILITY.
  1625 
  1626 
  1627 *** Document preparation ***
  1628 
  1629 * New generalized style concept for printing terms: @{foo (style) ...}
  1630 instead of @{foo_style style ...}  (old form is still retained for
  1631 backward compatibility).  Styles can be also applied for
  1632 antiquotations prop, term_type and typeof.
  1633 
  1634 
  1635 *** HOL ***
  1636 
  1637 * New proof method "smt" for a combination of first-order logic with
  1638 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  1639 fixed-size bitvectors; there is also basic support for higher-order
  1640 features (esp. lambda abstractions).  It is an incomplete decision
  1641 procedure based on external SMT solvers using the oracle mechanism;
  1642 for the SMT solver Z3, this method is proof-producing.  Certificates
  1643 are provided to avoid calling the external solvers solely for
  1644 re-checking proofs.  Due to a remote SMT service there is no need for
  1645 installing SMT solvers locally.  See src/HOL/SMT.
  1646 
  1647 * New commands to load and prove verification conditions generated by
  1648 the Boogie program verifier or derived systems (e.g. the Verifying C
  1649 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1650 
  1651 * New counterexample generator tool 'nitpick' based on the Kodkod
  1652 relational model finder.  See src/HOL/Tools/Nitpick and
  1653 src/HOL/Nitpick_Examples.
  1654 
  1655 * New commands 'code_pred' and 'values' to invoke the predicate
  1656 compiler and to enumerate values of inductive predicates.
  1657 
  1658 * A tabled implementation of the reflexive transitive closure.
  1659 
  1660 * New implementation of quickcheck uses generic code generator;
  1661 default generators are provided for all suitable HOL types, records
  1662 and datatypes.  Old quickcheck can be re-activated importing theory
  1663 Library/SML_Quickcheck.
  1664 
  1665 * New testing tool Mirabelle for automated proof tools.  Applies
  1666 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1667 every proof step in a theory.  To be used in batch mode via the
  1668 "mirabelle" utility.
  1669 
  1670 * New proof method "sos" (sum of squares) for nonlinear real
  1671 arithmetic (originally due to John Harison). It requires theory
  1672 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1673 works well in practice on quantifier-free real arithmetic with +, -,
  1674 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1675 inequalities between polynomials.  It makes use of external
  1676 semidefinite programming solvers.  Method "sos" generates a
  1677 certificate that can be pasted into the proof thus avoiding the need
  1678 to call an external tool every time the proof is checked.  See
  1679 src/HOL/Library/Sum_Of_Squares.
  1680 
  1681 * New method "linarith" invokes existing linear arithmetic decision
  1682 procedure only.
  1683 
  1684 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1685 
  1686 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1687 Causes full type information to be output to the ATPs.  This slows
  1688 ATPs down considerably but eliminates a source of unsound "proofs"
  1689 that fail later.
  1690 
  1691 * New method "metisFT": A version of metis that uses full type
  1692 information in order to avoid failures of proof reconstruction.
  1693 
  1694 * New evaluator "approximate" approximates an real valued term using
  1695 the same method as the approximation method.
  1696 
  1697 * Method "approximate" now supports arithmetic expressions as
  1698 boundaries of intervals and implements interval splitting and Taylor
  1699 series expansion.
  1700 
  1701 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1702 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1703 
  1704 * New theory SupInf of the supremum and infimum operators for sets of
  1705 reals.
  1706 
  1707 * New theory Probability, which contains a development of measure
  1708 theory, eventually leading to Lebesgue integration and probability.
  1709 
  1710 * Extended Multivariate Analysis to include derivation and Brouwer's
  1711 fixpoint theorem.
  1712 
  1713 * Reorganization of number theory, INCOMPATIBILITY:
  1714   - new number theory development for nat and int, in theories Divides
  1715     and GCD as well as in new session Number_Theory
  1716   - some constants and facts now suffixed with _nat and _int
  1717     accordingly
  1718   - former session NumberTheory now named Old_Number_Theory, including
  1719     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1720   - moved theory Pocklington from src/HOL/Library to
  1721     src/HOL/Old_Number_Theory
  1722 
  1723 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1724 lcm of finite and infinite sets. It is shown that they form a complete
  1725 lattice.
  1726 
  1727 * Class semiring_div requires superclass no_zero_divisors and proof of
  1728 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1729 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1730 generalized to class semiring_div, subsuming former theorems
  1731 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1732 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1733 INCOMPATIBILITY.
  1734 
  1735 * Refinements to lattice classes and sets:
  1736   - less default intro/elim rules in locale variant, more default
  1737     intro/elim rules in class variant: more uniformity
  1738   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1739     le_inf_iff
  1740   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1741     sup_aci)
  1742   - renamed ACI to inf_sup_aci
  1743   - new class "boolean_algebra"
  1744   - class "complete_lattice" moved to separate theory
  1745     "Complete_Lattice"; corresponding constants (and abbreviations)
  1746     renamed and with authentic syntax:
  1747     Set.Inf ~>    Complete_Lattice.Inf
  1748     Set.Sup ~>    Complete_Lattice.Sup
  1749     Set.INFI ~>   Complete_Lattice.INFI
  1750     Set.SUPR ~>   Complete_Lattice.SUPR
  1751     Set.Inter ~>  Complete_Lattice.Inter
  1752     Set.Union ~>  Complete_Lattice.Union
  1753     Set.INTER ~>  Complete_Lattice.INTER
  1754     Set.UNION ~>  Complete_Lattice.UNION
  1755   - authentic syntax for
  1756     Set.Pow
  1757     Set.image
  1758   - mere abbreviations:
  1759     Set.empty               (for bot)
  1760     Set.UNIV                (for top)
  1761     Set.inter               (for inf, formerly Set.Int)
  1762     Set.union               (for sup, formerly Set.Un)
  1763     Complete_Lattice.Inter  (for Inf)
  1764     Complete_Lattice.Union  (for Sup)
  1765     Complete_Lattice.INTER  (for INFI)
  1766     Complete_Lattice.UNION  (for SUPR)
  1767   - object-logic definitions as far as appropriate
  1768 
  1769 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1770 Un_subset_iff are explicitly deleted as default simp rules; then also
  1771 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1772 deleted to achieve the desired effect.
  1773 
  1774 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1775 rules by default any longer; the same applies to min_max.inf_absorb1
  1776 etc.  INCOMPATIBILITY.
  1777 
  1778 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1779 pred_set_conv by default.  INCOMPATIBILITY.
  1780 
  1781 * Power operations on relations and functions are now one dedicated
  1782 constant "compow" with infix syntax "^^".  Power operation on
  1783 multiplicative monoids retains syntax "^" and is now defined generic
  1784 in class power.  INCOMPATIBILITY.
  1785 
  1786 * Relation composition "R O S" now has a more standard argument order:
  1787 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1788 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1789 break, since the O_assoc rule was not rewritten like this.  Fix using
  1790 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1791 
  1792 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1793 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1794 INCOMPATIBILITY.
  1795 
  1796 * Most rules produced by inductive and datatype package have mandatory
  1797 prefixes.  INCOMPATIBILITY.
  1798 
  1799 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1800 the attribute of the same name.  Each of the theorems in the list
  1801 DERIV_intros assumes composition with an additional function and
  1802 matches a variable to the derivative, which has to be solved by the
  1803 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1804 of most elementary terms.  Former Maclauren.DERIV_tac and
  1805 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1806 INCOMPATIBILITY.
  1807 
  1808 * Code generator attributes follow the usual underscore convention:
  1809     code_unfold     replaces    code unfold
  1810     code_post       replaces    code post
  1811     etc.
  1812   INCOMPATIBILITY.
  1813 
  1814 * Renamed methods:
  1815     sizechange -> size_change
  1816     induct_scheme -> induction_schema
  1817   INCOMPATIBILITY.
  1818 
  1819 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1820 INCOMPATIBILITY, use "undefined" directly.
  1821 
  1822 * Renamed theorems:
  1823     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1824     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1825     Suc_plus1 -> Suc_eq_plus1
  1826     *anti_sym -> *antisym*
  1827     vector_less_eq_def -> vector_le_def
  1828   INCOMPATIBILITY.
  1829 
  1830 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1831 INCOMPATIBILITY.
  1832 
  1833 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1834 INCOMPATIBILITY.
  1835 
  1836 
  1837 *** HOLCF ***
  1838 
  1839 * Theory Representable defines a class "rep" of domains that are
  1840 representable (via an ep-pair) in the universal domain type "udom".
  1841 Instances are provided for all type constructors defined in HOLCF.
  1842 
  1843 * The 'new_domain' command is a purely definitional version of the
  1844 domain package, for representable domains.  Syntax is identical to the
  1845 old domain package.  The 'new_domain' package also supports indirect
  1846 recursion using previously-defined type constructors.  See
  1847 src/HOLCF/ex/New_Domain.thy for examples.
  1848 
  1849 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1850 on the left-hand side of an equation, and then performs
  1851 simplification.  Rewriting is done using rules declared with the
  1852 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1853 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1854 
  1855 * The pattern-match compiler in 'fixrec' can now handle constructors
  1856 with HOL function types.  Pattern-match combinators for the Pair
  1857 constructor are pre-configured.
  1858 
  1859 * The 'fixrec' package now produces better fixed-point induction rules
  1860 for mutually-recursive definitions:  Induction rules have conclusions
  1861 of the form "P foo bar" instead of "P <foo, bar>".
  1862 
  1863 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1864 been renamed to "below".  The name "below" now replaces "less" in many
  1865 theorem names.  (Legacy theorem names using "less" are still supported
  1866 as well.)
  1867 
  1868 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1869 patterns can be used to generate strictness rules, or to make
  1870 functions more strict (much like the bang-patterns supported by the
  1871 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1872 examples.
  1873 
  1874 
  1875 *** ML ***
  1876 
  1877 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1878 errors and run-time exceptions, including detailed source positions.
  1879 
  1880 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1881 identified entries, with some additional information such as source
  1882 position, logical grouping etc.
  1883 
  1884 * Theory and context data is now introduced by the simplified and
  1885 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1886 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1887 copy operation) is still available for some time.
  1888 
  1889 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1890 provides a high-level programming interface to synchronized state
  1891 variables with atomic update.  This works via pure function
  1892 application within a critical section -- its runtime should be as
  1893 short as possible; beware of deadlocks if critical code is nested,
  1894 either directly or indirectly via other synchronized variables!
  1895 
  1896 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1897 wraps raw ML references, explicitly indicating their non-thread-safe
  1898 behaviour.  The Isar toplevel keeps this structure open, to
  1899 accommodate Proof General as well as quick and dirty interactive
  1900 experiments with references.
  1901 
  1902 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1903 parallel tactical reasoning.
  1904 
  1905 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1906 are similar to SUBPROOF, but are slightly more flexible: only the
  1907 specified parts of the subgoal are imported into the context, and the
  1908 body tactic may introduce new subgoals and schematic variables.
  1909 
  1910 * Old tactical METAHYPS, which does not observe the proof context, has
  1911 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1912 or Subgoal.FOCUS etc.
  1913 
  1914 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  1915 functors have their own ML name space there is no point to mark them
  1916 separately.)  Minor INCOMPATIBILITY.
  1917 
  1918 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  1919 
  1920 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  1921 INCOMPATIBILITY.
  1922 
  1923 * Operations of structure Skip_Proof no longer require quick_and_dirty
  1924 mode, which avoids critical setmp.
  1925 
  1926 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  1927 combinators for "args".  INCOMPATIBILITY, need to use simplified
  1928 Attrib/Method.setup introduced in Isabelle2009.
  1929 
  1930 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  1931 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  1932 last resort.  INCOMPATIBILITY.
  1933 
  1934 * Display.pretty_thm now requires a proper context (cf. former
  1935 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  1936 or even Display.pretty_thm_without_context as last resort.
  1937 INCOMPATIBILITY.
  1938 
  1939 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  1940 Syntax.pretty_typ/term directly, preferably with proper context
  1941 instead of global theory.
  1942 
  1943 
  1944 *** System ***
  1945 
  1946 * Further fine tuning of parallel proof checking, scales up to 8 cores
  1947 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  1948 usedir option -q.
  1949 
  1950 * Support for additional "Isabelle components" via etc/components, see
  1951 also the system manual.
  1952 
  1953 * The isabelle makeall tool now operates on all components with
  1954 IsaMakefile, not just hardwired "logics".
  1955 
  1956 * Removed "compress" option from isabelle-process and isabelle usedir;
  1957 this is always enabled.
  1958 
  1959 * Discontinued support for Poly/ML 4.x versions.
  1960 
  1961 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  1962 on a given logic image.  This requires the lighttpd webserver and is
  1963 currently supported on Linux only.
  1964 
  1965 
  1966 
  1967 New in Isabelle2009 (April 2009)
  1968 --------------------------------
  1969 
  1970 *** General ***
  1971 
  1972 * Simplified main Isabelle executables, with less surprises on
  1973 case-insensitive file-systems (such as Mac OS).
  1974 
  1975   - The main Isabelle tool wrapper is now called "isabelle" instead of
  1976     "isatool."
  1977 
  1978   - The former "isabelle" alias for "isabelle-process" has been
  1979     removed (should rarely occur to regular users).
  1980 
  1981   - The former "isabelle-interface" and its alias "Isabelle" have been
  1982     removed (interfaces are now regular Isabelle tools).
  1983 
  1984 Within scripts and make files, the Isabelle environment variables
  1985 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  1986 respectively.  (The latter are still available as legacy feature.)
  1987 
  1988 The old isabelle-interface wrapper could react in confusing ways if
  1989 the interface was uninstalled or changed otherwise.  Individual
  1990 interface tool configuration is now more explicit, see also the
  1991 Isabelle system manual.  In particular, Proof General is now available
  1992 via "isabelle emacs".
  1993 
  1994 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  1995 purge installed copies of Isabelle executables and re-run "isabelle
  1996 install -p ...", or use symlinks.
  1997 
  1998 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  1999 old ~/isabelle, which was slightly non-standard and apt to cause
  2000 surprises on case-insensitive file-systems (such as Mac OS).
  2001 
  2002 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  2003 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  2004 care is required when using older releases of Isabelle.  Note that
  2005 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  2006 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  2007 
  2008 * Proofs of fully specified statements are run in parallel on
  2009 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  2010 a regular 4-core machine, if the initial heap space is made reasonably
  2011 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  2012 
  2013 * The main reference manuals ("isar-ref", "implementation", and
  2014 "system") have been updated and extended.  Formally checked references
  2015 as hyperlinks are now available uniformly.
  2016 
  2017 
  2018 *** Pure ***
  2019 
  2020 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  2021 respects.  The most important changes are listed below.  See the
  2022 Tutorial on Locales ("locales" manual) for details.
  2023 
  2024 - In locale expressions, instantiation replaces renaming.  Parameters
  2025 must be declared in a for clause.  To aid compatibility with previous
  2026 parameter inheritance, in locale declarations, parameters that are not
  2027 'touched' (instantiation position "_" or omitted) are implicitly added
  2028 with their syntax at the beginning of the for clause.
  2029 
  2030 - Syntax from abbreviations and definitions in locales is available in
  2031 locale expressions and context elements.  The latter is particularly
  2032 useful in locale declarations.
  2033 
  2034 - More flexible mechanisms to qualify names generated by locale
  2035 expressions.  Qualifiers (prefixes) may be specified in locale
  2036 expressions, and can be marked as mandatory (syntax: "name!:") or
  2037 optional (syntax "name?:").  The default depends for plain "name:"
  2038 depends on the situation where a locale expression is used: in
  2039 commands 'locale' and 'sublocale' prefixes are optional, in
  2040 'interpretation' and 'interpret' prefixes are mandatory.  The old
  2041 implicit qualifiers derived from the parameter names of a locale are
  2042 no longer generated.
  2043 
  2044 - Command "sublocale l < e" replaces "interpretation l < e".  The
  2045 instantiation clause in "interpretation" and "interpret" (square
  2046 brackets) is no longer available.  Use locale expressions.
  2047 
  2048 - When converting proof scripts, mandatory qualifiers in
  2049 'interpretation' and 'interpret' should be retained by default, even
  2050 if this is an INCOMPATIBILITY compared to former behavior.  In the
  2051 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  2052 in locale expressions range over a single locale instance only.
  2053 
  2054 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  2055 In existing theorem specifications replace the includes element by the
  2056 respective context elements of the included locale, omitting those
  2057 that are already present in the theorem specification.  Multiple
  2058 assume elements of a locale should be replaced by a single one
  2059 involving the locale predicate.  In the proof body, declarations (most
  2060 notably theorems) may be regained by interpreting the respective
  2061 locales in the proof context as required (command "interpret").
  2062 
  2063 If using "includes" in replacement of a target solely because the
  2064 parameter types in the theorem are not as general as in the target,
  2065 consider declaring a new locale with additional type constraints on
  2066 the parameters (context element "constrains").
  2067 
  2068 - Discontinued "locale (open)".  INCOMPATIBILITY.
  2069 
  2070 - Locale interpretation commands no longer attempt to simplify goal.
  2071 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  2072 methods intro_locales and unfold_locales to clarify.
  2073 
  2074 - Locale interpretation commands no longer accept interpretation
  2075 attributes.  INCOMPATIBILITY.
  2076 
  2077 * Class declaration: so-called "base sort" must not be given in import
  2078 list any longer, but is inferred from the specification.  Particularly
  2079 in HOL, write
  2080 
  2081     class foo = ...
  2082 
  2083 instead of
  2084 
  2085     class foo = type + ...
  2086 
  2087 * Class target: global versions of theorems stemming do not carry a
  2088 parameter prefix any longer.  INCOMPATIBILITY.
  2089 
  2090 * Class 'instance' command no longer accepts attached definitions.
  2091 INCOMPATIBILITY, use proper 'instantiation' target instead.
  2092 
  2093 * Recovered hiding of consts, which was accidentally broken in
  2094 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  2095 makes c inaccessible; consider using ``hide (open) const c'' instead.
  2096 
  2097 * Slightly more coherent Pure syntax, with updated documentation in
  2098 isar-ref manual.  Removed locales meta_term_syntax and
  2099 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  2100 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  2101 directly in regular applications.
  2102 
  2103 * There is a new syntactic category "float_const" for signed decimal
  2104 fractions (e.g. 123.45 or -123.45).
  2105 
  2106 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  2107 interface with 'setup' command instead.
  2108 
  2109 * Command 'local_setup' is similar to 'setup', but operates on a local
  2110 theory context.
  2111 
  2112 * The 'axiomatization' command now only works within a global theory
  2113 context.  INCOMPATIBILITY.
  2114 
  2115 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  2116 hypotheses.  Sorts required in the course of reasoning need to be
  2117 covered by the constraints in the initial statement, completed by the
  2118 type instance information of the background theory.  Non-trivial sort
  2119 hypotheses, which rarely occur in practice, may be specified via
  2120 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  2121 
  2122   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  2123 
  2124 The result contains an implicit sort hypotheses as before --
  2125 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  2126 normalization.
  2127 
  2128 * Generalized Isar history, with support for linear undo, direct state
  2129 addressing etc.
  2130 
  2131 * Changed defaults for unify configuration options:
  2132 
  2133   unify_trace_bound = 50 (formerly 25)
  2134   unify_search_bound = 60 (formerly 30)
  2135 
  2136 * Different bookkeeping for code equations (INCOMPATIBILITY):
  2137 
  2138   a) On theory merge, the last set of code equations for a particular
  2139      constant is taken (in accordance with the policy applied by other
  2140      parts of the code generator framework).
  2141 
  2142   b) Code equations stemming from explicit declarations (e.g. code
  2143      attribute) gain priority over default code equations stemming
  2144      from definition, primrec, fun etc.
  2145 
  2146 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  2147 
  2148 * Unified theorem tables for both code generators.  Thus [code
  2149 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  2150 
  2151 * Command 'find_consts' searches for constants based on type and name
  2152 patterns, e.g.
  2153 
  2154     find_consts "_ => bool"
  2155 
  2156 By default, matching is against subtypes, but it may be restricted to
  2157 the whole type.  Searching by name is possible.  Multiple queries are
  2158 conjunctive and queries may be negated by prefixing them with a
  2159 hyphen:
  2160 
  2161     find_consts strict: "_ => bool" name: "Int" -"int => int"
  2162 
  2163 * New 'find_theorems' criterion "solves" matches theorems that
  2164 directly solve the current goal (modulo higher-order unification).
  2165 
  2166 * Auto solve feature for main theorem statements: whenever a new goal
  2167 is stated, "find_theorems solves" is called; any theorems that could
  2168 solve the lemma directly are listed as part of the goal state.
  2169 Cf. associated options in Proof General Isabelle settings menu,
  2170 enabled by default, with reasonable timeout for pathological cases of
  2171 higher-order unification.
  2172 
  2173 
  2174 *** Document preparation ***
  2175 
  2176 * Antiquotation @{lemma} now imitates a regular terminal proof,
  2177 demanding keyword 'by' and supporting the full method expression
  2178 syntax just like the Isar command 'by'.
  2179 
  2180 
  2181 *** HOL ***
  2182 
  2183 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  2184 points Main and Complex_Main remain as before.
  2185 
  2186 * Logic image HOL-Plain provides a minimal HOL with the most important
  2187 tools available (inductive, datatype, primrec, ...).  This facilitates
  2188 experimentation and tool development.  Note that user applications
  2189 (and library theories) should never refer to anything below theory
  2190 Main, as before.
  2191 
  2192 * Logic image HOL-Main stops at theory Main, and thus facilitates
  2193 experimentation due to shorter build times.
  2194 
  2195 * Logic image HOL-NSA contains theories of nonstandard analysis which
  2196 were previously part of former HOL-Complex.  Entry point Hyperreal
  2197 remains valid, but theories formerly using Complex_Main should now use
  2198 new entry point Hypercomplex.
  2199 
  2200 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  2201 Posix processes.  Avoids potentially expensive forking of the ML
  2202 process.  New thread-based implementation also works on non-Unix
  2203 platforms (Cygwin).  Provers are no longer hardwired, but defined
  2204 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  2205 commands are covered in the isar-ref manual.
  2206 
  2207 * Wrapper scripts for remote SystemOnTPTP service allows to use
  2208 sledgehammer without local ATP installation (Vampire etc.). Other
  2209 provers may be included via suitable ML wrappers, see also
  2210 src/HOL/ATP_Linkup.thy.
  2211 
  2212 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  2213 menu.
  2214 
  2215 * The metis method no longer fails because the theorem is too trivial
  2216 (contains the empty clause).
  2217 
  2218 * The metis method now fails in the usual manner, rather than raising
  2219 an exception, if it determines that it cannot prove the theorem.
  2220 
  2221 * Method "coherent" implements a prover for coherent logic (see also
  2222 src/Tools/coherent.ML).
  2223 
  2224 * Constants "undefined" and "default" replace "arbitrary".  Usually
  2225 "undefined" is the right choice to replace "arbitrary", though
  2226 logically there is no difference.  INCOMPATIBILITY.
  2227 
  2228 * Command "value" now integrates different evaluation mechanisms.  The
  2229 result of the first successful evaluation mechanism is printed.  In
  2230 square brackets a particular named evaluation mechanisms may be
  2231 specified (currently, [SML], [code] or [nbe]).  See further
  2232 src/HOL/ex/Eval_Examples.thy.
  2233 
  2234 * Normalization by evaluation now allows non-leftlinear equations.
  2235 Declare with attribute [code nbe].
  2236 
  2237 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  2238 as the structured Isar versions "cases" and "induct", cf. the
  2239 corresponding "cases" and "induct" attributes.  Mutual induction rules
  2240 are now presented as a list of individual projections
  2241 (e.g. foo_bar.inducts for types foo and bar); the old format with
  2242 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  2243 rare situations a different rule is selected --- notably nested tuple
  2244 elimination instead of former prod.exhaust: use explicit (case_tac t
  2245 rule: prod.exhaust) here.
  2246 
  2247 * Attributes "cases", "induct", "coinduct" support "del" option.
  2248 
  2249 * Removed fact "case_split_thm", which duplicates "case_split".
  2250 
  2251 * The option datatype has been moved to a new theory Option.  Renamed
  2252 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  2253 
  2254 * New predicate "strict_mono" classifies strict functions on partial
  2255 orders.  With strict functions on linear orders, reasoning about
  2256 (in)equalities is facilitated by theorems "strict_mono_eq",
  2257 "strict_mono_less_eq" and "strict_mono_less".
  2258 
  2259 * Some set operations are now proper qualified constants with
  2260 authentic syntax.  INCOMPATIBILITY:
  2261 
  2262     op Int ~>   Set.Int
  2263     op Un ~>    Set.Un
  2264     INTER ~>    Set.INTER
  2265     UNION ~>    Set.UNION
  2266     Inter ~>    Set.Inter
  2267     Union ~>    Set.Union
  2268     {} ~>       Set.empty
  2269     UNIV ~>     Set.UNIV
  2270 
  2271 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  2272 theory Set.
  2273 
  2274 * Auxiliary class "itself" has disappeared -- classes without any
  2275 parameter are treated as expected by the 'class' command.
  2276 
  2277 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  2278 
  2279 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  2280 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  2281 
  2282 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  2283 method "approximation".  It proves formulas on real values by using
  2284 interval arithmetic.  In the formulas are also the transcendental
  2285 functions sin, cos, tan, atan, ln, exp and the constant pi are
  2286 allowed. For examples see
  2287 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  2288 
  2289 * Theory "Reflection" now resides in HOL/Library.
  2290 
  2291 * Entry point to Word library now simply named "Word".
  2292 INCOMPATIBILITY.
  2293 
  2294 * Made source layout more coherent with logical distribution
  2295 structure:
  2296 
  2297     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  2298     src/HOL/Library/Code_Message.thy ~> src/HOL/
  2299     src/HOL/Library/GCD.thy ~> src/HOL/
  2300     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  2301     src/HOL/Library/Parity.thy ~> src/HOL/
  2302     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  2303     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  2304     src/HOL/Real/Lubs.thy ~> src/HOL/
  2305     src/HOL/Real/PReal.thy ~> src/HOL/
  2306     src/HOL/Real/Rational.thy ~> src/HOL/
  2307     src/HOL/Real/RComplete.thy ~> src/HOL/
  2308     src/HOL/Real/RealDef.thy ~> src/HOL/
  2309     src/HOL/Real/RealPow.thy ~> src/HOL/
  2310     src/HOL/Real/Real.thy ~> src/HOL/
  2311     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  2312     src/HOL/Complex/Complex.thy ~> src/HOL/
  2313     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  2314     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  2315     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  2316     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  2317     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  2318     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  2319     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  2320     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  2321     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  2322     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  2323     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  2324     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  2325     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  2326     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  2327     src/HOL/Real/Float ~> src/HOL/Library/
  2328     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  2329     src/HOL/Real/RealVector.thy ~> src/HOL/
  2330 
  2331     src/HOL/arith_data.ML ~> src/HOL/Tools
  2332     src/HOL/hologic.ML ~> src/HOL/Tools
  2333     src/HOL/simpdata.ML ~> src/HOL/Tools
  2334     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  2335     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  2336     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  2337     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  2338     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  2339     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  2340     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  2341 
  2342     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  2343     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  2344     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  2345     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  2346     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  2347     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  2348 
  2349 * If methods "eval" and "evaluation" encounter a structured proof
  2350 state with !!/==>, only the conclusion is evaluated to True (if
  2351 possible), avoiding strange error messages.
  2352 
  2353 * Method "sizechange" automates termination proofs using (a
  2354 modification of) the size-change principle.  Requires SAT solver.  See
  2355 src/HOL/ex/Termination.thy for examples.
  2356 
  2357 * Simplifier: simproc for let expressions now unfolds if bound
  2358 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  2359 
  2360 * Method "arith": Linear arithmetic now ignores all inequalities when
  2361 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  2362 
  2363 * New attribute "arith" for facts that should always be used
  2364 automatically by arithmetic. It is intended to be used locally in
  2365 proofs, e.g.
  2366 
  2367   assumes [arith]: "x > 0"
  2368 
  2369 Global usage is discouraged because of possible performance impact.
  2370 
  2371 * New classes "top" and "bot" with corresponding operations "top" and
  2372 "bot" in theory Orderings; instantiation of class "complete_lattice"
  2373 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  2374 
  2375 * Changed definition lemma "less_fun_def" in order to provide an
  2376 instance for preorders on functions; use lemma "less_le" instead.
  2377 INCOMPATIBILITY.
  2378 
  2379 * Theory Orderings: class "wellorder" moved here, with explicit
  2380 induction rule "less_induct" as assumption.  For instantiation of
  2381 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  2382 INCOMPATIBILITY.
  2383 
  2384 * Theory Orderings: added class "preorder" as superclass of "order".
  2385 INCOMPATIBILITY: Instantiation proofs for order, linorder
  2386 etc. slightly changed.  Some theorems named order_class.* now named
  2387 preorder_class.*.
  2388 
  2389 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  2390 "diag" to "Id_on".
  2391 
  2392 * Theory Finite_Set: added a new fold combinator of type
  2393 
  2394   ('a => 'b => 'b) => 'b => 'a set => 'b
  2395 
  2396 Occasionally this is more convenient than the old fold combinator
  2397 which is now defined in terms of the new one and renamed to
  2398 fold_image.
  2399 
  2400 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  2401 and "ring_simps" have been replaced by "algebra_simps" (which can be
  2402 extended with further lemmas!).  At the moment both still exist but
  2403 the former will disappear at some point.
  2404 
  2405 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  2406 class recpower.  Type-specific simp rules for various recpower types
  2407 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  2408 
  2409 rat_power_0    -> power_0
  2410 rat_power_Suc  -> power_Suc
  2411 realpow_0      -> power_0
  2412 realpow_Suc    -> power_Suc
  2413 complexpow_0   -> power_0
  2414 complexpow_Suc -> power_Suc
  2415 power_poly_0   -> power_0
  2416 power_poly_Suc -> power_Suc
  2417 
  2418 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  2419 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  2420 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  2421 of lemmas from Divides has been generalized from nat to class
  2422 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  2423 renames resulting from duplicate elimination:
  2424 
  2425     dvd_def_mod ~>          dvd_eq_mod_eq_0
  2426     zero_dvd_iff ~>         dvd_0_left_iff
  2427     dvd_0 ~>                dvd_0_right
  2428     DIVISION_BY_ZERO_DIV ~> div_by_0
  2429     DIVISION_BY_ZERO_MOD ~> mod_by_0
  2430     mult_div ~>             div_mult_self2_is_id
  2431     mult_mod ~>             mod_mult_self2_is_0
  2432 
  2433 * Theory IntDiv: removed many lemmas that are instances of class-based
  2434 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  2435 rename old lemmas as follows:
  2436 
  2437 dvd_diff               -> nat_dvd_diff
  2438 dvd_zminus_iff         -> dvd_minus_iff
  2439 mod_add1_eq            -> mod_add_eq
  2440 mod_mult1_eq           -> mod_mult_right_eq
  2441 mod_mult1_eq'          -> mod_mult_left_eq
  2442 mod_mult_distrib_mod   -> mod_mult_eq
  2443 nat_mod_add_left_eq    -> mod_add_left_eq
  2444 nat_mod_add_right_eq   -> mod_add_right_eq
  2445 nat_mod_div_trivial    -> mod_div_trivial
  2446 nat_mod_mod_trivial    -> mod_mod_trivial
  2447 zdiv_zadd_self1        -> div_add_self1
  2448 zdiv_zadd_self2        -> div_add_self2
  2449 zdiv_zmult_self1       -> div_mult_self2_is_id
  2450 zdiv_zmult_self2       -> div_mult_self1_is_id
  2451 zdvd_triv_left         -> dvd_triv_left
  2452 zdvd_triv_right        -> dvd_triv_right
  2453 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  2454 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  2455 zmod_zadd_left_eq      -> mod_add_left_eq
  2456 zmod_zadd_right_eq     -> mod_add_right_eq
  2457 zmod_zadd_self1        -> mod_add_self1
  2458 zmod_zadd_self2        -> mod_add_self2
  2459 zmod_zadd1_eq          -> mod_add_eq
  2460 zmod_zdiff1_eq         -> mod_diff_eq
  2461 zmod_zdvd_zmod         -> mod_mod_cancel
  2462 zmod_zmod_cancel       -> mod_mod_cancel
  2463 zmod_zmult_self1       -> mod_mult_self2_is_0
  2464 zmod_zmult_self2       -> mod_mult_self1_is_0
  2465 zmod_1                 -> mod_by_1
  2466 zdiv_1                 -> div_by_1
  2467 zdvd_abs1              -> abs_dvd_iff
  2468 zdvd_abs2              -> dvd_abs_iff
  2469 zdvd_refl              -> dvd_refl
  2470 zdvd_trans             -> dvd_trans
  2471 zdvd_zadd              -> dvd_add
  2472 zdvd_zdiff             -> dvd_diff
  2473 zdvd_zminus_iff        -> dvd_minus_iff
  2474 zdvd_zminus2_iff       -> minus_dvd_iff
  2475 zdvd_zmultD            -> dvd_mult_right
  2476 zdvd_zmultD2           -> dvd_mult_left
  2477 zdvd_zmult_mono        -> mult_dvd_mono
  2478 zdvd_0_right           -> dvd_0_right
  2479 zdvd_0_left            -> dvd_0_left_iff
  2480 zdvd_1_left            -> one_dvd
  2481 zminus_dvd_iff         -> minus_dvd_iff
  2482 
  2483 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  2484 
  2485 * The real numbers offer decimal input syntax: 12.34 is translated
  2486 into 1234/10^2. This translation is not reversed upon output.
  2487 
  2488 * Theory Library/Polynomial defines an abstract type 'a poly of
  2489 univariate polynomials with coefficients of type 'a.  In addition to
  2490 the standard ring operations, it also supports div and mod.  Code
  2491 generation is also supported, using list-style constructors.
  2492 
  2493 * Theory Library/Inner_Product defines a class of real_inner for real
  2494 inner product spaces, with an overloaded operation inner :: 'a => 'a
  2495 => real.  Class real_inner is a subclass of real_normed_vector from
  2496 theory RealVector.
  2497 
  2498 * Theory Library/Product_Vector provides instances for the product
  2499 type 'a * 'b of several classes from RealVector and Inner_Product.
  2500 Definitions of addition, subtraction, scalar multiplication, norms,
  2501 and inner products are included.
  2502 
  2503 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  2504 addition to the field operations, numerals and case syntax are also
  2505 supported.
  2506 
  2507 * Theory Library/Diagonalize provides constructive version of Cantor's
  2508 first diagonalization argument.
  2509 
  2510 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  2511 zlcm (for int); carried together from various gcd/lcm developements in
  2512 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  2513 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  2514 may recover tupled syntax as follows:
  2515 
  2516     hide (open) const gcd
  2517     abbreviation gcd where
  2518       "gcd == (%(a, b). GCD.gcd a b)"
  2519     notation (output)
  2520       GCD.gcd ("gcd '(_, _')")
  2521 
  2522 The same works for lcm, zgcd, zlcm.
  2523 
  2524 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  2525 instantiations for algebraic structures.  Removed some duplicate
  2526 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  2527 
  2528 * ML antiquotation @{code} takes a constant as argument and generates
  2529 corresponding code in background and inserts name of the corresponding
  2530 resulting ML value/function/datatype constructor binding in place.
  2531 All occurrences of @{code} with a single ML block are generated
  2532 simultaneously.  Provides a generic and safe interface for
  2533 instrumentalizing code generation.  See
  2534 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  2535 In future you ought to refrain from ad-hoc compiling generated SML
  2536 code on the ML toplevel.  Note that (for technical reasons) @{code}
  2537 cannot refer to constants for which user-defined serializations are
  2538 set.  Refer to the corresponding ML counterpart directly in that
  2539 cases.
  2540 
  2541 * Command 'rep_datatype': instead of theorem names the command now
  2542 takes a list of terms denoting the constructors of the type to be
  2543 represented as datatype.  The characteristic theorems have to be
  2544 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  2545 have disappeared in favour of existing ones:
  2546 
  2547     unit_induct                 ~> unit.induct
  2548     prod_induct                 ~> prod.induct
  2549     sum_induct                  ~> sum.induct
  2550     Suc_Suc_eq                  ~> nat.inject
  2551     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  2552 
  2553 
  2554 *** HOL-Algebra ***
  2555 
  2556 * New locales for orders and lattices where the equivalence relation
  2557 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  2558 locales use a record structure with field eq for the equivalence.
  2559 
  2560 * New theory of factorial domains.
  2561 
  2562 * Units_l_inv and Units_r_inv are now simp rules by default.
  2563 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  2564 and/or r_inv will now also require deletion of these lemmas.
  2565 
  2566 * Renamed the following theorems, INCOMPATIBILITY:
  2567 
  2568 UpperD ~> Upper_memD
  2569 LowerD ~> Lower_memD
  2570 least_carrier ~> least_closed
  2571 greatest_carrier ~> greatest_closed
  2572 greatest_Lower_above ~> greatest_Lower_below
  2573 one_zero ~> carrier_one_zero
  2574 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  2575 
  2576 
  2577 *** HOL-Nominal ***
  2578 
  2579 * Nominal datatypes can now contain type-variables.
  2580 
  2581 * Commands 'nominal_inductive' and 'equivariance' work with local
  2582 theory targets.
  2583 
  2584 * Nominal primrec can now works with local theory targets and its
  2585 specification syntax now conforms to the general format as seen in
  2586 'inductive' etc.
  2587 
  2588 * Method "perm_simp" honours the standard simplifier attributes
  2589 (no_asm), (no_asm_use) etc.
  2590 
  2591 * The new predicate #* is defined like freshness, except that on the
  2592 left hand side can be a set or list of atoms.
  2593 
  2594 * Experimental command 'nominal_inductive2' derives strong induction
  2595 principles for inductive definitions.  In contrast to
  2596 'nominal_inductive', which can only deal with a fixed number of
  2597 binders, it can deal with arbitrary expressions standing for sets of
  2598 atoms to be avoided.  The only inductive definition we have at the
  2599 moment that needs this generalisation is the typing rule for Lets in
  2600 the algorithm W:
  2601 
  2602  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  2603  -----------------------------------------------------------------
  2604          Gamma |- Let x be t1 in t2 : T2
  2605 
  2606 In this rule one wants to avoid all the binders that are introduced by
  2607 "close Gamma T1".  We are looking for other examples where this
  2608 feature might be useful.  Please let us know.
  2609 
  2610 
  2611 *** HOLCF ***
  2612 
  2613 * Reimplemented the simplification procedure for proving continuity
  2614 subgoals.  The new simproc is extensible; users can declare additional
  2615 continuity introduction rules with the attribute [cont2cont].
  2616 
  2617 * The continuity simproc now uses a different introduction rule for
  2618 solving continuity subgoals on terms with lambda abstractions.  In
  2619 some rare cases the new simproc may fail to solve subgoals that the
  2620 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  2621 Potential INCOMPATIBILITY.
  2622 
  2623 * Command 'fixrec': specification syntax now conforms to the general
  2624 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  2625 examples.  INCOMPATIBILITY.
  2626 
  2627 
  2628 *** ZF ***
  2629 
  2630 * Proof of Zorn's Lemma for partial orders.
  2631 
  2632 
  2633 *** ML ***
  2634 
  2635 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  2636 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  2637 depends on multithreading, so timouts will not work before Poly/ML
  2638 5.2.1!
  2639 
  2640 * High-level support for concurrent ML programming, see
  2641 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  2642 particularly convenient to organize independent functional
  2643 computations.  The concept of "synchronized variables" provides a
  2644 higher-order interface for components with shared state, avoiding the
  2645 delicate details of mutexes and condition variables.  (Requires
  2646 Poly/ML 5.2.1 or later.)
  2647 
  2648 * ML bindings produced via Isar commands are stored within the Isar
  2649 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2650 become thread-safe and work with undo as expected (concerning
  2651 top-level bindings, not side-effects on global references).
  2652 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2653 compiler at runtime; really global bindings need to be given outside a
  2654 theory.  (Requires Poly/ML 5.2 or later.)
  2655 
  2656 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2657 context.  Top-level ML bindings are stored within the proof context in
  2658 a purely sequential fashion, disregarding the nested proof structure.
  2659 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2660 proof.  (Requires Poly/ML 5.2 or later.)
  2661 
  2662 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2663 and Method.setup, as well as Isar commands 'attribute_setup' and
  2664 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2665 existing code accordingly, or use plain 'setup' together with old
  2666 Method.add_method.
  2667 
  2668 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2669 to 'a -> thm, while results are always tagged with an authentic oracle
  2670 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2671 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2672 accordingly.  Note that extra performance may be gained by producing
  2673 the cterm carefully, avoiding slow Thm.cterm_of.
  2674 
  2675 * Simplified interface for defining document antiquotations via
  2676 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2677 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2678 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2679 examples.
  2680 
  2681 * More systematic treatment of long names, abstract name bindings, and
  2682 name space operations.  Basic operations on qualified names have been
  2683 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2684 Long_Name.append.  Old type bstring has been mostly replaced by
  2685 abstract type binding (see structure Binding), which supports precise
  2686 qualification by packages and local theory targets, as well as proper
  2687 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2688 bstring values into Binding.name, or better pass through abstract
  2689 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2690 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2691 
  2692 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2693 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2694 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2695 
  2696 * Disposed old type and term read functions (Sign.read_def_typ,
  2697 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2698 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2699 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2700 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2701 resort for legacy applications.
  2702 
  2703 * Disposed old declarations, tactics, tactic combinators that refer to
  2704 the simpset or claset of an implicit theory (such as Addsimps,
  2705 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2706 embedded ML text, or local_simpset_of with a proper context passed as
  2707 explicit runtime argument.
  2708 
  2709 * Rules and tactics that read instantiations (read_instantiate,
  2710 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2711 context, which is required for parsing and type-checking.  Moreover,
  2712 the variables are specified as plain indexnames, not string encodings
  2713 thereof.  INCOMPATIBILITY.
  2714 
  2715 * Generic Toplevel.add_hook interface allows to analyze the result of
  2716 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2717 for theorem dependency output of transactions resulting in a new
  2718 theory state.
  2719 
  2720 * ML antiquotations: block-structured compilation context indicated by
  2721 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2722 
  2723   @{binding name}                         - basic name binding
  2724   @{let ?pat = term}                      - term abbreviation (HO matching)
  2725   @{note name = fact}                     - fact abbreviation
  2726   @{thm fact}                             - singleton fact (with attributes)
  2727   @{thms fact}                            - general fact (with attributes)
  2728   @{lemma prop by method}                 - singleton goal
  2729   @{lemma prop by meth1 meth2}            - singleton goal
  2730   @{lemma prop1 ... propN by method}      - general goal
  2731   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2732   @{lemma (open) ...}                     - open derivation
  2733 
  2734 
  2735 *** System ***
  2736 
  2737 * The Isabelle "emacs" tool provides a specific interface to invoke
  2738 Proof General / Emacs, with more explicit failure if that is not
  2739 installed (the old isabelle-interface script silently falls back on
  2740 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2741 installation location of the Proof General distribution.
  2742 
  2743 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2744 the Isabelle process into a JVM/Scala application.  See
  2745 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2746 process wrapper has been discontinued.)
  2747 
  2748 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2749 
  2750 * Various status messages (with exact source position information) are
  2751 emitted, if proper markup print mode is enabled.  This allows
  2752 user-interface components to provide detailed feedback on internal
  2753 prover operations.
  2754 
  2755 
  2756 
  2757 New in Isabelle2008 (June 2008)
  2758 -------------------------------
  2759 
  2760 *** General ***
  2761 
  2762 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2763 and updated, with formally checked references as hyperlinks.
  2764 
  2765 * Theory loader: use_thy (and similar operations) no longer set the
  2766 implicit ML context, which was occasionally hard to predict and in
  2767 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2768 provides a proper context already.
  2769 
  2770 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2771 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2772 'use' within a theory file will do the job.
  2773 
  2774 * Name space merge now observes canonical order, i.e. the second space
  2775 is inserted into the first one, while existing entries in the first
  2776 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2777 swap theory imports.
  2778 
  2779 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2780 INCOMPATIBILITY in identifier syntax etc.
  2781 
  2782 * Outer syntax: string tokens no longer admit escaped white space,
  2783 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2784 white space without escapes.
  2785 
  2786 * Outer syntax: string tokens may contain arbitrary character codes
  2787 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2788 "foo_bar".
  2789 
  2790 
  2791 *** Pure ***
  2792 
  2793 * Context-dependent token translations.  Default setup reverts locally
  2794 fixed variables, and adds hilite markup for undeclared frees.
  2795 
  2796 * Unused theorems can be found using the new command 'unused_thms'.
  2797 There are three ways of invoking it:
  2798 
  2799 (1) unused_thms
  2800      Only finds unused theorems in the current theory.
  2801 
  2802 (2) unused_thms thy_1 ... thy_n -
  2803      Finds unused theorems in the current theory and all of its ancestors,
  2804      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2805 
  2806 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2807      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2808      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2809      their ancestors.
  2810 
  2811 In order to increase the readability of the list produced by
  2812 unused_thms, theorems that have been created by a particular instance
  2813 of a theory command such as 'inductive' or 'function' are considered
  2814 to belong to the same "group", meaning that if at least one theorem in
  2815 this group is used, the other theorems in the same group are no longer
  2816 reported as unused.  Moreover, if all theorems in the group are
  2817 unused, only one theorem in the group is displayed.
  2818 
  2819 Note that proof objects have to be switched on in order for
  2820 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2821 usually the case when using Proof General with the default settings).
  2822 
  2823 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2824 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2825 duplicate fact bindings, or even accidental fact duplications.  Note
  2826 that tools may maintain dynamically scoped facts systematically, using
  2827 PureThy.add_thms_dynamic.
  2828 
  2829 * Command 'hide' now allows to hide from "fact" name space as well.
  2830 
  2831 * Eliminated destructive theorem database, simpset, claset, and
  2832 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2833 update of theories within ML code.
  2834 
  2835 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2836 INCOMPATIBILITY, object-logics depending on former Pure require
  2837 additional setup PureThy.old_appl_syntax_setup; object-logics
  2838 depending on former CPure need to refer to Pure.
  2839 
  2840 * Commands 'use' and 'ML' are now purely functional, operating on
  2841 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2842 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2843 INCOMPATIBILITY.
  2844 
  2845 * Command 'setup': discontinued implicit version with ML reference.
  2846 
  2847 * Instantiation target allows for simultaneous specification of class
  2848 instance operations together with an instantiation proof.
  2849 Type-checking phase allows to refer to class operations uniformly.
  2850 See src/HOL/Complex/Complex.thy for an Isar example and
  2851 src/HOL/Library/Eval.thy for an ML example.
  2852 
  2853 * Indexing of literal facts: be more serious about including only
  2854 facts from the visible specification/proof context, but not the
  2855 background context (locale etc.).  Affects `prop` notation and method
  2856 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2857 situations.
  2858 
  2859 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2860 "(open)" option, which used to expose internal bound variables to the
  2861 proof text.
  2862 
  2863 * Isar statements: removed obsolete case "rule_context".
  2864 INCOMPATIBILITY, better use explicit fixes/assumes.
  2865 
  2866 * Locale proofs: default proof step now includes 'unfold_locales';
  2867 hence 'proof' without argument may be used to unfold locale
  2868 predicates.
  2869 
  2870 
  2871 *** Document preparation ***
  2872 
  2873 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2874 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2875 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2876 spot); renamed link color from "darkblue" to "linkcolor" (default
  2877 value unchanged, can be redefined via \definecolor); no longer sets
  2878 "a4paper" option (unnecessary or even intrusive).
  2879 
  2880 * Antiquotation @{lemma A method} proves proposition A by the given
  2881 method (either a method name or a method name plus (optional) method
  2882 arguments in parentheses) and prints A just like @{prop A}.
  2883 
  2884 
  2885 *** HOL ***
  2886 
  2887 * New primrec package.  Specification syntax conforms in style to
  2888 definition/function/....  No separate induction rule is provided.  The
  2889 "primrec" command distinguishes old-style and new-style specifications
  2890 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2891 When adjusting theories, beware: constants stemming from new-style
  2892 primrec specifications have authentic syntax.
  2893 
  2894 * Metis prover is now an order of magnitude faster, and also works
  2895 with multithreading.
  2896 
  2897 * Metis: the maximum number of clauses that can be produced from a
  2898 theorem is now given by the attribute max_clauses.  Theorems that
  2899 exceed this number are ignored, with a warning printed.
  2900 
  2901 * Sledgehammer no longer produces structured proofs by default. To
  2902 enable, declare [[sledgehammer_full = true]].  Attributes
  2903 reconstruction_modulus, reconstruction_sorts renamed
  2904 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2905 
  2906 * Method "induct_scheme" derives user-specified induction rules
  2907 from well-founded induction and completeness of patterns. This factors
  2908 out some operations that are done internally by the function package
  2909 and makes them available separately.  See
  2910 src/HOL/ex/Induction_Scheme.thy for examples.
  2911 
  2912 * More flexible generation of measure functions for termination
  2913 proofs: Measure functions can be declared by proving a rule of the
  2914 form "is_measure f" and giving it the [measure_function] attribute.
  2915 The "is_measure" predicate is logically meaningless (always true), and
  2916 just guides the heuristic.  To find suitable measure functions, the
  2917 termination prover sets up the goal "is_measure ?f" of the appropriate
  2918 type and generates all solutions by prolog-style backwards proof using
  2919 the declared rules.
  2920 
  2921 This setup also deals with rules like 
  2922 
  2923   "is_measure f ==> is_measure (list_size f)"
  2924 
  2925 which accommodates nested datatypes that recurse through lists.
  2926 Similar rules are predeclared for products and option types.
  2927 
  2928 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  2929 
  2930   INCOMPATIBILITIES:
  2931 
  2932   - Definitions of overloaded constants on sets have to be replaced by
  2933     definitions on => and bool.
  2934 
  2935   - Some definitions of overloaded operators on sets can now be proved
  2936     using the definitions of the operators on => and bool.  Therefore,
  2937     the following theorems have been renamed:
  2938 
  2939       subset_def   -> subset_eq
  2940       psubset_def  -> psubset_eq
  2941       set_diff_def -> set_diff_eq
  2942       Compl_def    -> Compl_eq
  2943       Sup_set_def  -> Sup_set_eq
  2944       Inf_set_def  -> Inf_set_eq
  2945       sup_set_def  -> sup_set_eq
  2946       inf_set_def  -> inf_set_eq
  2947 
  2948   - Due to the incompleteness of the HO unification algorithm, some
  2949     rules such as subst may require manual instantiation, if some of
  2950     the unknowns in the rule is a set.
  2951 
  2952   - Higher order unification and forward proofs:
  2953     The proof pattern
  2954 
  2955       have "P (S::'a set)" <...>
  2956       then have "EX S. P S" ..
  2957 
  2958     no longer works (due to the incompleteness of the HO unification
  2959     algorithm) and must be replaced by the pattern
  2960 
  2961       have "EX S. P S"
  2962       proof
  2963         show "P S" <...>
  2964       qed
  2965 
  2966   - Calculational reasoning with subst (or similar rules):
  2967     The proof pattern
  2968 
  2969       have "P (S::'a set)" <...>
  2970       also have "S = T" <...>
  2971       finally have "P T" .
  2972 
  2973     no longer works (for similar reasons as the previous example) and
  2974     must be replaced by something like
  2975 
  2976       have "P (S::'a set)" <...>
  2977       moreover have "S = T" <...>
  2978       ultimately have "P T" by simp
  2979 
  2980   - Tactics or packages written in ML code:
  2981     Code performing pattern matching on types via
  2982 
  2983       Type ("set", [T]) => ...
  2984 
  2985     must be rewritten. Moreover, functions like strip_type or
  2986     binder_types no longer return the right value when applied to a
  2987     type of the form
  2988 
  2989       T1 => ... => Tn => U => bool
  2990 
  2991     rather than
  2992 
  2993       T1 => ... => Tn => U set
  2994 
  2995 * Merged theories Wellfounded_Recursion, Accessible_Part and
  2996 Wellfounded_Relations to theory Wellfounded.
  2997 
  2998 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  2999 
  3000 * Class finite no longer treats UNIV as class parameter.  Use class
  3001 enum from theory Library/Enum instead to achieve a similar effect.
  3002 INCOMPATIBILITY.
  3003 
  3004 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  3005 and "Cons".  INCOMPATIBILITY.
  3006 
  3007 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  3008 Potential INCOMPATIBILITY.
  3009 
  3010 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  3011 injective_fst_snd removed, use split_eta and prod_eqI instead.
  3012 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  3013 
  3014 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  3015 the same name in theory Orderings:
  3016 
  3017   less_trans
  3018   less_linear
  3019   le_imp_less_or_eq
  3020   le_less_trans
  3021   less_le_trans
  3022   less_not_sym
  3023   less_asym
  3024 
  3025 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  3026 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  3027 and different variable names.
  3028 
  3029 * Library/Option_ord.thy: Canonical order on option type.
  3030 
  3031 * Library/RBT.thy: Red-black trees, an efficient implementation of
  3032 finite maps.
  3033 
  3034 * Library/Countable.thy: Type class for countable types.
  3035 
  3036 * Theory Int: The representation of numerals has changed.  The infix
  3037 operator BIT and the bit datatype with constructors B0 and B1 have
  3038 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  3039 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  3040 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  3041 accordingly.
  3042 
  3043 * Theory Nat: definition of <= and < on natural numbers no longer
  3044 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  3045 le_def and less_def have disappeared.  Consider lemmas not_less
  3046 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  3047 
  3048 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  3049 (whose purpose mainly is for various fold_set functionals) have been
  3050 abandoned in favor of the existing algebraic classes
  3051 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  3052 lower_semilattice (resp. upper_semilattice) and linorder.
  3053 INCOMPATIBILITY.
  3054 
  3055 * Theory Transitive_Closure: induct and cases rules now declare proper
  3056 case_names ("base" and "step").  INCOMPATIBILITY.
  3057 
  3058 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  3059 lattices.  The form set-specific version is available as
  3060 Inductive.lfp_ordinal_induct_set.
  3061 
  3062 * Renamed theorems "power.simps" to "power_int.simps".
  3063 INCOMPATIBILITY.
  3064 
  3065 * Class semiring_div provides basic abstract properties of semirings
  3066 with division and modulo operations.  Subsumes former class dvd_mod.
  3067 
  3068 * Merged theories IntDef, Numeral and IntArith into unified theory
  3069 Int.  INCOMPATIBILITY.
  3070 
  3071 * Theory Library/Code_Index: type "index" now represents natural
  3072 numbers rather than integers.  INCOMPATIBILITY.
  3073 
  3074 * New class "uminus" with operation "uminus" (split of from class
  3075 "minus" which now only has operation "minus", binary).
  3076 INCOMPATIBILITY.
  3077 
  3078 * Constants "card", "internal_split", "option_map" now with authentic
  3079 syntax.  INCOMPATIBILITY.
  3080 
  3081 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  3082 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  3083 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  3084 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  3085 Sup_set_def, le_def, less_def, option_map_def now with object
  3086 equality.  INCOMPATIBILITY.
  3087 
  3088 * Records. Removed K_record, and replaced it by pure lambda term
  3089 %x. c. The simplifier setup is now more robust against eta expansion.
  3090 INCOMPATIBILITY: in cases explicitly referring to K_record.
  3091 
  3092 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  3093 
  3094 * Library/ListVector: new theory of arithmetic vector operations.
  3095 
  3096 * Library/Order_Relation: new theory of various orderings as sets of
  3097 pairs.  Defines preorders, partial orders, linear orders and
  3098 well-orders on sets and on types.
  3099 
  3100 
  3101 *** ZF ***
  3102 
  3103 * Renamed some theories to allow to loading both ZF and HOL in the
  3104 same session:
  3105 
  3106   Datatype  -> Datatype_ZF
  3107   Inductive -> Inductive_ZF
  3108   Int       -> Int_ZF
  3109   IntDiv    -> IntDiv_ZF
  3110   Nat       -> Nat_ZF
  3111   List      -> List_ZF
  3112   Main      -> Main_ZF
  3113 
  3114 INCOMPATIBILITY: ZF theories that import individual theories below
  3115 Main might need to be adapted.  Regular theory Main is still
  3116 available, as trivial extension of Main_ZF.
  3117 
  3118 
  3119 *** ML ***
  3120 
  3121 * ML within Isar: antiquotation @{const name} or @{const
  3122 name(typargs)} produces statically-checked Const term.
  3123 
  3124 * Functor NamedThmsFun: data is available to the user as dynamic fact
  3125 (of the same name).  Removed obsolete print command.
  3126 
  3127 * Removed obsolete "use_legacy_bindings" function.
  3128 
  3129 * The ``print mode'' is now a thread-local value derived from a global
  3130 template (the former print_mode reference), thus access becomes
  3131 non-critical.  The global print_mode reference is for session
  3132 management only; user-code should use print_mode_value,
  3133 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  3134 
  3135 * Functions system/system_out provide a robust way to invoke external
  3136 shell commands, with propagation of interrupts (requires Poly/ML
  3137 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  3138 
  3139 
  3140 *** System ***
  3141 
  3142 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  3143 in accordance with Proof General 3.7, which prefers GNU emacs.
  3144 
  3145 * isatool tty runs Isabelle process with plain tty interaction;
  3146 optional line editor may be specified via ISABELLE_LINE_EDITOR
  3147 setting, the default settings attempt to locate "ledit" and "rlwrap".
  3148 
  3149 * isatool browser now works with Cygwin as well, using general
  3150 "javapath" function defined in Isabelle process environment.
  3151 
  3152 * YXML notation provides a simple and efficient alternative to
  3153 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  3154 isatool yxml as described in the Isabelle system manual.
  3155 
  3156 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  3157 provides general wrapper for managing an Isabelle process in a robust
  3158 fashion, with ``cooked'' output from stdin/stderr.
  3159 
  3160 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  3161 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  3162 
  3163 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  3164 way of changing the user's settings is via
  3165 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  3166 script.
  3167 
  3168 * Multithreading.max_threads := 0 refers to the number of actual CPU
  3169 cores of the underlying machine, which is a good starting point for
  3170 optimal performance tuning.  The corresponding usedir option -M allows
  3171 "max" as an alias for "0".  WARNING: does not work on certain versions
  3172 of Mac OS (with Poly/ML 5.1).
  3173 
  3174 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  3175 adverse effect of Isabelle flooding interactive front-ends (notably
  3176 ProofGeneral / XEmacs).
  3177 
  3178 
  3179 
  3180 New in Isabelle2007 (November 2007)
  3181 -----------------------------------
  3182 
  3183 *** General ***
  3184 
  3185 * More uniform information about legacy features, notably a
  3186 warning/error of "Legacy feature: ...", depending on the state of the
  3187 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  3188 legacy features will disappear eventually.
  3189 
  3190 * Theory syntax: the header format ``theory A = B + C:'' has been
  3191 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  3192 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  3193 
  3194 * Theory syntax: the old non-Isar theory file format has been
  3195 discontinued altogether.  Note that ML proof scripts may still be used
  3196 with Isar theories; migration is usually quite simple with the ML
  3197 function use_legacy_bindings.  INCOMPATIBILITY.
  3198 
  3199 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  3200 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  3201 quotes.
  3202 
  3203 * Theory loader: be more serious about observing the static theory
  3204 header specifications (including optional directories), but not the
  3205 accidental file locations of previously successful loads.  The strict
  3206 update policy of former update_thy is now already performed by
  3207 use_thy, so the former has been removed; use_thys updates several
  3208 theories simultaneously, just as 'imports' within a theory header
  3209 specification, but without merging the results.  Potential
  3210 INCOMPATIBILITY: may need to refine theory headers and commands
  3211 ROOT.ML which depend on load order.
  3212 
  3213 * Theory loader: optional support for content-based file
  3214 identification, instead of the traditional scheme of full physical
  3215 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  3216 (cf. the system manual).  The new scheme allows to work with
  3217 non-finished theories in persistent session images, such that source
  3218 files may be moved later on without requiring reloads.
  3219 
  3220 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3221 file (with the same base name as the theory) are considered a legacy
  3222 feature, which will disappear eventually. Even now, the theory loader
  3223 no longer maintains dependencies on such files.
  3224 
  3225 * Syntax: the scope for resolving ambiguities via type-inference is
  3226 now limited to individual terms, instead of whole simultaneous
  3227 specifications as before. This greatly reduces the complexity of the
  3228 syntax module and improves flexibility by separating parsing and
  3229 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  3230 'fixes' etc.) are required in rare situations.
  3231 
  3232 * Syntax: constants introduced by new-style packages ('definition',
  3233 'abbreviation' etc.) are passed through the syntax module in
  3234 ``authentic mode''. This means that associated mixfix annotations
  3235 really stick to such constants, independently of potential name space
  3236 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  3237 trees are represented slightly differently, may need to adapt syntax
  3238 translations accordingly. Use CONST marker in 'translations' and
  3239 @{const_syntax} antiquotation in 'parse_translation' etc.
  3240 
  3241 * Legacy goal package: reduced interface to the bare minimum required
  3242 to keep existing proof scripts running.  Most other user-level
  3243 functions are now part of the OldGoals structure, which is *not* open
  3244 by default (consider isatool expandshort before open OldGoals).
  3245 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  3246 these tend to cause confusion about the actual goal (!) context being
  3247 used here, which is not necessarily the same as the_context().
  3248 
  3249 * Command 'find_theorems': supports "*" wild-card in "name:"
  3250 criterion; "with_dups" option.  Certain ProofGeneral versions might
  3251 support a specific search form (see ProofGeneral/CHANGES).
  3252 
  3253 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  3254 by default, which means that "prems" (and also "fixed variables") are
  3255 suppressed from proof state output.  Note that the ProofGeneral
  3256 settings mechanism allows to change and save options persistently, but
  3257 older versions of Isabelle will fail to start up if a negative prems
  3258 limit is imposed.
  3259 
  3260 * Local theory targets may be specified by non-nested blocks of
  3261 ``context/locale/class ... begin'' followed by ``end''.  The body may
  3262 contain definitions, theorems etc., including any derived mechanism
  3263 that has been implemented on top of these primitives.  This concept
  3264 generalizes the existing ``theorem (in ...)'' towards more versatility
  3265 and scalability.
  3266 
  3267 * Proof General interface: proper undo of final 'end' command;
  3268 discontinued Isabelle/classic mode (ML proof scripts).
  3269 
  3270 
  3271 *** Document preparation ***
  3272 
  3273 * Added antiquotation @{theory name} which prints the given name,
  3274 after checking that it refers to a valid ancestor theory in the
  3275 current context.
  3276 
  3277 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  3278 check the given source text as ML type/structure, printing verbatim.
  3279 
  3280 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  3281 "c args == rhs" given in the current context.  (Any number of
  3282 arguments may be given on the LHS.)
  3283 
  3284 
  3285 *** Pure ***
  3286 
  3287 * The 'class' package offers a combination of axclass and locale to
  3288 achieve Haskell-like type classes in Isabelle.  Definitions and
  3289 theorems within a class context produce both relative results (with
  3290 implicit parameters according to the locale context), and polymorphic
  3291 constants with qualified polymorphism (according to the class
  3292 context).  Within the body context of a 'class' target, a separate
  3293 syntax layer ("user space type system") takes care of converting
  3294 between global polymorphic consts and internal locale representation.
  3295 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  3296 "isatool doc classes" provides a tutorial.
  3297 
  3298 * Generic code generator framework allows to generate executable
  3299 code for ML and Haskell (including Isabelle classes).  A short usage
  3300 sketch:
  3301 
  3302     internal compilation:
  3303         export_code <list of constants (term syntax)> in SML
  3304     writing SML code to a file:
  3305         export_code <list of constants (term syntax)> in SML <filename>
  3306     writing OCaml code to a file:
  3307         export_code <list of constants (term syntax)> in OCaml <filename>
  3308     writing Haskell code to a bunch of files:
  3309         export_code <list of constants (term syntax)> in Haskell <filename>
  3310 
  3311     evaluating closed propositions to True/False using code generation:
  3312         method ``eval''
  3313 
  3314 Reasonable default setup of framework in HOL.
  3315 
  3316 Theorem attributs for selecting and transforming function equations theorems:
  3317 
  3318     [code fun]:        select a theorem as function equation for a specific constant
  3319     [code fun del]:    deselect a theorem as function equation for a specific constant
  3320     [code inline]:     select an equation theorem for unfolding (inlining) in place
  3321     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  3322 
  3323 User-defined serializations (target in {SML, OCaml, Haskell}):
  3324 
  3325     code_const <and-list of constants (term syntax)>
  3326       {(target) <and-list of const target syntax>}+
  3327 
  3328     code_type <and-list of type constructors>
  3329       {(target) <and-list of type target syntax>}+
  3330 
  3331     code_instance <and-list of instances>
  3332       {(target)}+
  3333         where instance ::= <type constructor> :: <class>
  3334 
  3335     code_class <and_list of classes>
  3336       {(target) <and-list of class target syntax>}+
  3337         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  3338 
  3339 code_instance and code_class only are effective to target Haskell.
  3340 
  3341 For example usage see src/HOL/ex/Codegenerator.thy and
  3342 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  3343 generation from Isabelle/HOL theories is available via "isatool doc
  3344 codegen".
  3345 
  3346 * Code generator: consts in 'consts_code' Isar commands are now
  3347 referred to by usual term syntax (including optional type
  3348 annotations).
  3349 
  3350 * Command 'no_translations' removes translation rules from theory
  3351 syntax.
  3352 
  3353 * Overloaded definitions are now actually checked for acyclic
  3354 dependencies.  The overloading scheme is slightly more general than
  3355 that of Haskell98, although Isabelle does not demand an exact
  3356 correspondence to type class and instance declarations.
  3357 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  3358 exotic versions of overloading -- at the discretion of the user!
  3359 
  3360 Polymorphic constants are represented via type arguments, i.e. the
  3361 instantiation that matches an instance against the most general
  3362 declaration given in the signature.  For example, with the declaration
  3363 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  3364 as c(nat).  Overloading is essentially simultaneous structural
  3365 recursion over such type arguments.  Incomplete specification patterns
  3366 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  3367 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  3368 Command 'print_theory' outputs the normalized system of recursive
  3369 equations, see section "definitions".
  3370 
  3371 * Configuration options are maintained within the theory or proof
  3372 context (with name and type bool/int/string), providing a very simple
  3373 interface to a poor-man's version of general context data.  Tools may
  3374 declare options in ML (e.g. using Attrib.config_int) and then refer to
  3375 these values using Config.get etc.  Users may change options via an
  3376 associated attribute of the same name.  This form of context
  3377 declaration works particularly well with commands 'declare' or
  3378 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  3379 very easy to avoid global references, which would not observe Isar
  3380 toplevel undo/redo and fail to work with multithreading.
  3381 
  3382 Various global ML references of Pure and HOL have been turned into
  3383 configuration options:
  3384 
  3385   Unify.search_bound		unify_search_bound
  3386   Unify.trace_bound		unify_trace_bound
  3387   Unify.trace_simp		unify_trace_simp
  3388   Unify.trace_types		unify_trace_types
  3389   Simplifier.simp_depth_limit	simp_depth_limit
  3390   Blast.depth_limit		blast_depth_limit
  3391   DatatypeProp.dtK		datatype_distinctness_limit
  3392   fast_arith_neq_limit  	fast_arith_neq_limit
  3393   fast_arith_split_limit	fast_arith_split_limit
  3394 
  3395 * Named collections of theorems may be easily installed as context
  3396 data using the functor NamedThmsFun (see also
  3397 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  3398 attributes; there is also a toplevel print command.  This facility is
  3399 just a common case of general context data, which is the preferred way
  3400 for anything more complex than just a list of facts in canonical
  3401 order.
  3402 
  3403 * Isar: command 'declaration' augments a local theory by generic
  3404 declaration functions written in ML.  This enables arbitrary content
  3405 being added to the context, depending on a morphism that tells the
  3406 difference of the original declaration context wrt. the application
  3407 context encountered later on.
  3408 
  3409 * Isar: proper interfaces for simplification procedures.  Command
  3410 'simproc_setup' declares named simprocs (with match patterns, and body
  3411 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  3412 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  3413 
  3414 * Isar: an extra pair of brackets around attribute declarations
  3415 abbreviates a theorem reference involving an internal dummy fact,
  3416 which will be ignored later --- only the effect of the attribute on
  3417 the background context will persist.  This form of in-place
  3418 declarations is particularly useful with commands like 'declare' and
  3419 'using', for example ``have A using [[simproc a]] by simp''.
  3420 
  3421 * Isar: method "assumption" (and implicit closing of subproofs) now
  3422 takes simple non-atomic goal assumptions into account: after applying
  3423 an assumption as a rule the resulting subgoals are solved by atomic
  3424 assumption steps.  This is particularly useful to finish 'obtain'
  3425 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  3426 without referring to the original premise "!!x. P x ==> thesis" in the
  3427 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  3428 more permissive.
  3429 
  3430 * Isar: implicit use of prems from the Isar proof context is
  3431 considered a legacy feature.  Common applications like ``have A .''
  3432 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  3433 referencing facts explicitly here improves readability and
  3434 maintainability of proof texts.
  3435 
  3436 * Isar: improper proof element 'guess' is like 'obtain', but derives
  3437 the obtained context from the course of reasoning!  For example:
  3438 
  3439   assume "EX x y. A x & B y"   -- "any previous fact"
  3440   then guess x and y by clarify
  3441 
  3442 This technique is potentially adventurous, depending on the facts and
  3443 proof tools being involved here.
  3444 
  3445 * Isar: known facts from the proof context may be specified as literal
  3446 propositions, using ASCII back-quote syntax.  This works wherever
  3447 named facts used to be allowed so far, in proof commands, proof
  3448 methods, attributes etc.  Literal facts are retrieved from the context
  3449 according to unification of type and term parameters.  For example,
  3450 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  3451 theorems in the current context, then these are valid literal facts:
  3452 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  3453 
  3454 There is also a proof method "fact" which does the same composition
  3455 for explicit goal states, e.g. the following proof texts coincide with
  3456 certain special cases of literal facts:
  3457 
  3458   have "A" by fact                 ==  note `A`
  3459   have "A ==> B" by fact           ==  note `A ==> B`
  3460   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  3461   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  3462 
  3463 * Isar: ":" (colon) is no longer a symbolic identifier character in
  3464 outer syntax.  Thus symbolic identifiers may be used without
  3465 additional white space in declarations like this: ``assume *: A''.
  3466 
  3467 * Isar: 'print_facts' prints all local facts of the current context,
  3468 both named and unnamed ones.
  3469 
  3470 * Isar: 'def' now admits simultaneous definitions, e.g.:
  3471 
  3472   def x == "t" and y == "u"
  3473 
  3474 * Isar: added command 'unfolding', which is structurally similar to
  3475 'using', but affects both the goal state and facts by unfolding given
  3476 rewrite rules.  Thus many occurrences of the 'unfold' method or
  3477 'unfolded' attribute may be replaced by first-class proof text.
  3478 
  3479 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  3480 and command 'unfolding' now all support object-level equalities
  3481 (potentially conditional).  The underlying notion of rewrite rule is
  3482 analogous to the 'rule_format' attribute, but *not* that of the
  3483 Simplifier (which is usually more generous).
  3484 
  3485 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  3486 premises of a theorem by n. Useful in conjunction with drule.
  3487 
  3488 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  3489 method expression within a sandbox consisting of the first N
  3490 sub-goals, which need to exist.  For example, ``simp_all [3]''
  3491 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  3492 simplifies all new goals that emerge from applying rule foo to the
  3493 originally first one.
  3494 
  3495 * Isar: schematic goals are no longer restricted to higher-order
  3496 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  3497 expected.
  3498 
  3499 * Isar: the conclusion of a long theorem statement is now either
  3500 'shows' (a simultaneous conjunction, as before), or 'obtains'
  3501 (essentially a disjunction of cases with local parameters and
  3502 assumptions).  The latter allows to express general elimination rules
  3503 adequately; in this notation common elimination rules look like this:
  3504 
  3505   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  3506     assumes "EX x. P x"
  3507     obtains x where "P x"
  3508 
  3509   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  3510     assumes "A & B"
  3511     obtains A and B
  3512 
  3513   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  3514     assumes "A | B"
  3515     obtains
  3516       A
  3517     | B
  3518 
  3519 The subsequent classical rules even refer to the formal "thesis"
  3520 explicitly:
  3521 
  3522   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  3523     obtains "~ thesis"
  3524 
  3525   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  3526     obtains "thesis ==> something"
  3527 
  3528 The actual proof of an 'obtains' statement is analogous to that of the
  3529 Isar proof element 'obtain', only that there may be several cases.
  3530 Optional case names may be specified in parentheses; these will be
  3531 available both in the present proof and as annotations in the
  3532 resulting rule, for later use with the 'cases' method (cf. attribute
  3533 case_names).
  3534 
  3535 * Isar: the assumptions of a long theorem statement are available as
  3536 "assms" fact in the proof context.  This is more appropriate than the
  3537 (historical) "prems", which refers to all assumptions of the current
  3538 context, including those from the target locale, proof body etc.
  3539 
  3540 * Isar: 'print_statement' prints theorems from the current theory or
  3541 proof context in long statement form, according to the syntax of a
  3542 top-level lemma.
  3543 
  3544 * Isar: 'obtain' takes an optional case name for the local context
  3545 introduction rule (default "that").
  3546 
  3547 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  3548 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  3549 to occur.
  3550 
  3551 * Pure: syntax "CONST name" produces a fully internalized constant
  3552 according to the current context.  This is particularly useful for
  3553 syntax translations that should refer to internal constant
  3554 representations independently of name spaces.
  3555 
  3556 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  3557 instead of "FOO ". This allows multiple binder declarations to coexist
  3558 in the same context.  INCOMPATIBILITY.
  3559 
  3560 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  3561 primitive that also works in a locale context (both for constants and
  3562 fixed variables). Type declaration and internal syntactic representation
  3563 of given constants retrieved from the context. Likewise, the
  3564 'no_notation' command allows to remove given syntax annotations from the
  3565 current context.
  3566 
  3567 * Isar/locales: new derived specification elements 'axiomatization',
  3568 'definition', 'abbreviation', which support type-inference, admit
  3569 object-level specifications (equality, equivalence).  See also the
  3570 isar-ref manual.  Examples:
  3571 
  3572   axiomatization
  3573     eq  (infix "===" 50) where
  3574     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  3575 
  3576   definition "f x y = x + y + 1"
  3577   definition g where "g x = f x x"
  3578 
  3579   abbreviation
  3580     neq  (infix "=!=" 50) where
  3581     "x =!= y == ~ (x === y)"
  3582 
  3583 These specifications may be also used in a locale context.  Then the
  3584 constants being introduced depend on certain fixed parameters, and the
  3585 constant name is qualified by the locale base name.  An internal
  3586 abbreviation takes care for convenient input and output, making the
  3587 parameters implicit and using the original short name.  See also
  3588 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  3589 entities from a monomorphic theory.
  3590 
  3591 Presently, abbreviations are only available 'in' a target locale, but
  3592 not inherited by general import expressions.  Also note that
  3593 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  3594 'translations' in common applications.  The "no_abbrevs" print mode
  3595 prevents folding of abbreviations in term output.
  3596 
  3597 Concrete syntax is attached to specified constants in internal form,
  3598 independently of name spaces.  The parse tree representation is
  3599 slightly different -- use 'notation' instead of raw 'syntax', and
  3600 'translations' with explicit "CONST" markup to accommodate this.
  3601 
  3602 * Pure/Isar: unified syntax for new-style specification mechanisms
  3603 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  3604 full type inference and dummy patterns ("_").  For example:
  3605 
  3606   definition "K x _ = x"
  3607 
  3608   inductive conj for A B
  3609   where "A ==> B ==> conj A B"
  3610 
  3611 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  3612 the current context.  Print mode "no_abbrevs" prevents inversion of
  3613 abbreviations on output.
  3614 
  3615 * Isar/locales: improved parameter handling: use of locales "var" and
  3616 "struct" no longer necessary; - parameter renamings are no longer
  3617 required to be injective.  For example, this allows to define
  3618 endomorphisms as locale endom = homom mult mult h.
  3619 
  3620 * Isar/locales: changed the way locales with predicates are defined.
  3621 Instead of accumulating the specification, the imported expression is
  3622 now an interpretation.  INCOMPATIBILITY: different normal form of
  3623 locale expressions.  In particular, in interpretations of locales with
  3624 predicates, goals repesenting already interpreted fragments are not
  3625 removed automatically.  Use methods `intro_locales' and
  3626 `unfold_locales'; see below.
  3627 
  3628 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  3629 provide backward reasoning on locales predicates.  The methods are
  3630 aware of interpretations and discharge corresponding goals.
  3631 `intro_locales' is less aggressive then `unfold_locales' and does not
  3632 unfold predicates to assumptions.
  3633 
  3634 * Isar/locales: the order in which locale fragments are accumulated
  3635 has changed.  This enables to override declarations from fragments due
  3636 to interpretations -- for example, unwanted simp rules.
  3637 
  3638 * Isar/locales: interpretation in theories and proof contexts has been
  3639 extended.  One may now specify (and prove) equations, which are
  3640 unfolded in interpreted theorems.  This is useful for replacing
  3641 defined concepts (constants depending on locale parameters) by
  3642 concepts already existing in the target context.  Example:
  3643 
  3644   interpretation partial_order ["op <= :: [int, int] => bool"]
  3645     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3646 
  3647 Typically, the constant `partial_order.less' is created by a
  3648 definition specification element in the context of locale
  3649 partial_order.
  3650 
  3651 * Method "induct": improved internal context management to support
  3652 local fixes and defines on-the-fly. Thus explicit meta-level
  3653 connectives !!  and ==> are rarely required anymore in inductive goals
  3654 (using object-logic connectives for this purpose has been long
  3655 obsolete anyway). Common proof patterns are explained in
  3656 src/HOL/Induct/Common_Patterns.thy, see also
  3657 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3658 examples.
  3659 
  3660 * Method "induct": improved handling of simultaneous goals. Instead of
  3661 introducing object-level conjunction, the statement is now split into
  3662 several conclusions, while the corresponding symbolic cases are nested
  3663 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3664 see src/HOL/Induct/Common_Patterns.thy, for example.
  3665 
  3666 * Method "induct": mutual induction rules are now specified as a list
  3667 of rule sharing the same induction cases. HOL packages usually provide
  3668 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3669 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3670 mutual induction rules differently, i.e. like this:
  3671 
  3672   (induct rule: foo_bar.inducts)
  3673   (induct set: foo bar)
  3674   (induct pred: foo bar)
  3675   (induct type: foo bar)
  3676 
  3677 The ML function ProjectRule.projections turns old-style rules into the
  3678 new format.
  3679 
  3680 * Method "coinduct": dual of induction, see
  3681 src/HOL/Library/Coinductive_List.thy for various examples.
  3682 
  3683 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3684 considered a legacy feature.
  3685 
  3686 * Attribute "symmetric" produces result with standardized schematic
  3687 variables (index 0).  Potential INCOMPATIBILITY.
  3688 
  3689 * Simplifier: by default the simplifier trace only shows top level
  3690 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3691 default. Thus there is less danger of being flooded by the trace. The
  3692 trace indicates where parts have been suppressed.
  3693   
  3694 * Provers/classical: removed obsolete classical version of elim_format
  3695 attribute; classical elim/dest rules are now treated uniformly when
  3696 manipulating the claset.
  3697 
  3698 * Provers/classical: stricter checks to ensure that supplied intro,
  3699 dest and elim rules are well-formed; dest and elim rules must have at
  3700 least one premise.
  3701 
  3702 * Provers/classical: attributes dest/elim/intro take an optional
  3703 weight argument for the rule (just as the Pure versions).  Weights are
  3704 ignored by automated tools, but determine the search order of single
  3705 rule steps.
  3706 
  3707 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3708 where the body does not mention the bound variable.  Note that dummy
  3709 patterns implicitly depend on their context of bounds, which makes
  3710 "{_. _}" match any set comprehension as expected.  Potential
  3711 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3712 constant "_idtdummy" in the binding position.
  3713 
  3714 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3715 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3716 for example "A -> B" => "Pi A (%_. B)".
  3717 
  3718 * Pure: 'class_deps' command visualizes the subclass relation, using
  3719 the graph browser tool.
  3720 
  3721 * Pure: 'print_theory' now suppresses certain internal declarations by
  3722 default; use '!' option for full details.
  3723 
  3724 
  3725 *** HOL ***
  3726 
  3727 * Method "metis" proves goals by applying the Metis general-purpose
  3728 resolution prover (see also http://gilith.com/software/metis/).
  3729 Examples are in the directory MetisExamples.  WARNING: the
  3730 Isabelle/HOL-Metis integration does not yet work properly with
  3731 multi-threading.
  3732   
  3733 * Command 'sledgehammer' invokes external automatic theorem provers as
  3734 background processes.  It generates calls to the "metis" method if
  3735 successful. These can be pasted into the proof.  Users do not have to
  3736 wait for the automatic provers to return.  WARNING: does not really
  3737 work with multi-threading.
  3738 
  3739 * New "auto_quickcheck" feature tests outermost goal statements for
  3740 potential counter-examples.  Controlled by ML references
  3741 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3742 5000 milliseconds).  Fails silently if statements is outside of
  3743 executable fragment, or any other codgenerator problem occurs.
  3744 
  3745 * New constant "undefined" with axiom "undefined x = undefined".
  3746 
  3747 * Added class "HOL.eq", allowing for code generation with polymorphic
  3748 equality.
  3749 
  3750 * Some renaming of class constants due to canonical name prefixing in
  3751 the new 'class' package:
  3752 
  3753     HOL.abs ~> HOL.abs_class.abs
  3754     HOL.divide ~> HOL.divide_class.divide
  3755     0 ~> HOL.zero_class.zero
  3756     1 ~> HOL.one_class.one
  3757     op + ~> HOL.plus_class.plus
  3758     op - ~> HOL.minus_class.minus
  3759     uminus ~> HOL.minus_class.uminus
  3760     op * ~> HOL.times_class.times
  3761     op < ~> HOL.ord_class.less
  3762     op <= > HOL.ord_class.less_eq
  3763     Nat.power ~> Power.power_class.power
  3764     Nat.size ~> Nat.size_class.size
  3765     Numeral.number_of ~> Numeral.number_class.number_of
  3766     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3767     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3768     Orderings.min ~> Orderings.ord_class.min
  3769     Orderings.max ~> Orderings.ord_class.max
  3770     Divides.op div ~> Divides.div_class.div
  3771     Divides.op mod ~> Divides.div_class.mod
  3772     Divides.op dvd ~> Divides.div_class.dvd
  3773 
  3774 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3775 
  3776 a) User-defined constants using any of the names "plus", "minus",
  3777 "times", "less" or "less_eq". The standard syntax translations for
  3778 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3779 names.
  3780 
  3781 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3782 INCOMPATIBILITY: use more specific names.
  3783 
  3784 c) Permutative equations (e.g. "a + b = b + a")
  3785 Since the change of names also changes the order of terms, permutative
  3786 rewrite rules may get applied in a different order. Experience shows
  3787 that this is rarely the case (only two adaptions in the whole Isabelle
  3788 distribution).  INCOMPATIBILITY: rewrite proofs
  3789 
  3790 d) ML code directly refering to constant names
  3791 This in general only affects hand-written proof tactics, simprocs and
  3792 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3793 Consider using @{const_name} antiquotation.
  3794 
  3795 * New class "default" with associated constant "default".
  3796 
  3797 * Function "sgn" is now overloaded and available on int, real, complex
  3798 (and other numeric types), using class "sgn".  Two possible defs of
  3799 sgn are given as equational assumptions in the classes sgn_if and
  3800 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3801 INCOMPATIBILITY.
  3802 
  3803 * Locale "partial_order" now unified with class "order" (cf. theory
  3804 Orderings), added parameter "less".  INCOMPATIBILITY.
  3805 
  3806 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3807 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3808 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3809 
  3810 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3811 changed order of proof goals in instance proofs.
  3812 
  3813 * The transitivity reasoner for partial and linear orders is set up
  3814 for classes "order" and "linorder".  Instances of the reasoner are available
  3815 in all contexts importing or interpreting the corresponding locales.
  3816 Method "order" invokes the reasoner separately; the reasoner
  3817 is also integrated with the Simplifier as a solver.  Diagnostic
  3818 command 'print_orders' shows the available instances of the reasoner
  3819 in the current context.
  3820 
  3821 * Localized monotonicity predicate in theory "Orderings"; integrated
  3822 lemmas max_of_mono and min_of_mono with this predicate.
  3823 INCOMPATIBILITY.
  3824 
  3825 * Formulation of theorem "dense" changed slightly due to integration
  3826 with new class dense_linear_order.
  3827 
  3828 * Uniform lattice theory development in HOL.
  3829 
  3830     constants "meet" and "join" now named "inf" and "sup"
  3831     constant "Meet" now named "Inf"
  3832 
  3833     classes "meet_semilorder" and "join_semilorder" now named
  3834       "lower_semilattice" and "upper_semilattice"
  3835     class "lorder" now named "lattice"
  3836     class "comp_lat" now named "complete_lattice"
  3837 
  3838     Instantiation of lattice classes allows explicit definitions
  3839     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3840 
  3841   INCOMPATIBILITY.  Theorem renames:
  3842 
  3843     meet_left_le            ~> inf_le1
  3844     meet_right_le           ~> inf_le2
  3845     join_left_le            ~> sup_ge1
  3846     join_right_le           ~> sup_ge2
  3847     meet_join_le            ~> inf_sup_ord
  3848     le_meetI                ~> le_infI
  3849     join_leI                ~> le_supI
  3850     le_meet                 ~> le_inf_iff
  3851     le_join                 ~> ge_sup_conv
  3852     meet_idempotent         ~> inf_idem
  3853     join_idempotent         ~> sup_idem
  3854     meet_comm               ~> inf_commute
  3855     join_comm               ~> sup_commute
  3856     meet_leI1               ~> le_infI1
  3857     meet_leI2               ~> le_infI2
  3858     le_joinI1               ~> le_supI1
  3859     le_joinI2               ~> le_supI2
  3860     meet_assoc              ~> inf_assoc
  3861     join_assoc              ~> sup_assoc
  3862     meet_left_comm          ~> inf_left_commute
  3863     meet_left_idempotent    ~> inf_left_idem
  3864     join_left_comm          ~> sup_left_commute
  3865     join_left_idempotent    ~> sup_left_idem
  3866     meet_aci                ~> inf_aci
  3867     join_aci                ~> sup_aci
  3868     le_def_meet             ~> le_iff_inf
  3869     le_def_join             ~> le_iff_sup
  3870     join_absorp2            ~> sup_absorb2
  3871     join_absorp1            ~> sup_absorb1
  3872     meet_absorp1            ~> inf_absorb1
  3873     meet_absorp2            ~> inf_absorb2
  3874     meet_join_absorp        ~> inf_sup_absorb
  3875     join_meet_absorp        ~> sup_inf_absorb
  3876     distrib_join_le         ~> distrib_sup_le
  3877     distrib_meet_le         ~> distrib_inf_le
  3878 
  3879     add_meet_distrib_left   ~> add_inf_distrib_left
  3880     add_join_distrib_left   ~> add_sup_distrib_left
  3881     is_join_neg_meet        ~> is_join_neg_inf
  3882     is_meet_neg_join        ~> is_meet_neg_sup
  3883     add_meet_distrib_right  ~> add_inf_distrib_right
  3884     add_join_distrib_right  ~> add_sup_distrib_right
  3885     add_meet_join_distribs  ~> add_sup_inf_distribs
  3886     join_eq_neg_meet        ~> sup_eq_neg_inf
  3887     meet_eq_neg_join        ~> inf_eq_neg_sup
  3888     add_eq_meet_join        ~> add_eq_inf_sup
  3889     meet_0_imp_0            ~> inf_0_imp_0
  3890     join_0_imp_0            ~> sup_0_imp_0
  3891     meet_0_eq_0             ~> inf_0_eq_0
  3892     join_0_eq_0             ~> sup_0_eq_0
  3893     neg_meet_eq_join        ~> neg_inf_eq_sup
  3894     neg_join_eq_meet        ~> neg_sup_eq_inf
  3895     join_eq_if              ~> sup_eq_if
  3896 
  3897     mono_meet               ~> mono_inf
  3898     mono_join               ~> mono_sup
  3899     meet_bool_eq            ~> inf_bool_eq
  3900     join_bool_eq            ~> sup_bool_eq
  3901     meet_fun_eq             ~> inf_fun_eq
  3902     join_fun_eq             ~> sup_fun_eq
  3903     meet_set_eq             ~> inf_set_eq
  3904     join_set_eq             ~> sup_set_eq
  3905     meet1_iff               ~> inf1_iff
  3906     meet2_iff               ~> inf2_iff
  3907     meet1I                  ~> inf1I
  3908     meet2I                  ~> inf2I
  3909     meet1D1                 ~> inf1D1
  3910     meet2D1                 ~> inf2D1
  3911     meet1D2                 ~> inf1D2
  3912     meet2D2                 ~> inf2D2
  3913     meet1E                  ~> inf1E
  3914     meet2E                  ~> inf2E
  3915     join1_iff               ~> sup1_iff
  3916     join2_iff               ~> sup2_iff
  3917     join1I1                 ~> sup1I1
  3918     join2I1                 ~> sup2I1
  3919     join1I1                 ~> sup1I1
  3920     join2I2                 ~> sup1I2
  3921     join1CI                 ~> sup1CI
  3922     join2CI                 ~> sup2CI
  3923     join1E                  ~> sup1E
  3924     join2E                  ~> sup2E
  3925 
  3926     is_meet_Meet            ~> is_meet_Inf
  3927     Meet_bool_def           ~> Inf_bool_def
  3928     Meet_fun_def            ~> Inf_fun_def
  3929     Meet_greatest           ~> Inf_greatest
  3930     Meet_lower              ~> Inf_lower
  3931     Meet_set_def            ~> Inf_set_def
  3932 
  3933     Sup_def                 ~> Sup_Inf
  3934     Sup_bool_eq             ~> Sup_bool_def
  3935     Sup_fun_eq              ~> Sup_fun_def
  3936     Sup_set_eq              ~> Sup_set_def
  3937 
  3938     listsp_meetI            ~> listsp_infI
  3939     listsp_meet_eq          ~> listsp_inf_eq
  3940 
  3941     meet_min                ~> inf_min
  3942     join_max                ~> sup_max
  3943 
  3944 * Added syntactic class "size"; overloaded constant "size" now has
  3945 type "'a::size ==> bool"
  3946 
  3947 * Internal reorganisation of `size' of datatypes: size theorems
  3948 "foo.size" are no longer subsumed by "foo.simps" (but are still
  3949 simplification rules by default!); theorems "prod.size" now named
  3950 "*.size".
  3951 
  3952 * Class "div" now inherits from class "times" rather than "type".
  3953 INCOMPATIBILITY.
  3954 
  3955 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  3956 Linorder etc.  have disappeared; operations defined in terms of
  3957 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  3958 
  3959 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  3960 
  3961 * HOL-Word: New extensive library and type for generic, fixed size
  3962 machine words, with arithemtic, bit-wise, shifting and rotating
  3963 operations, reflection into int, nat, and bool lists, automation for
  3964 linear arithmetic (by automatic reflection into nat or int), including
  3965 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  3966 arithmetic type classes, supporting automatic simplification of
  3967 numerals on all operations.
  3968 
  3969 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  3970 
  3971 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  3972 
  3973 * Code generator library theories:
  3974   - Code_Integer represents HOL integers by big integer literals in target
  3975     languages.
  3976   - Code_Char represents HOL characters by character literals in target
  3977     languages.
  3978   - Code_Char_chr like Code_Char, but also offers treatment of character
  3979     codes; includes Code_Integer.
  3980   - Executable_Set allows to generate code for finite sets using lists.
  3981   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  3982     denominator).
  3983   - Executable_Real implements a subset of real numbers, namly those
  3984     representable by rational numbers.
  3985   - Efficient_Nat implements natural numbers by integers, which in general will
  3986     result in higher efficency; pattern matching with 0/Suc is eliminated;
  3987     includes Code_Integer.
  3988   - Code_Index provides an additional datatype index which is mapped to
  3989     target-language built-in integers.
  3990   - Code_Message provides an additional datatype message_string which is isomorphic to
  3991     strings; messages are mapped to target-language strings.
  3992 
  3993 * New package for inductive predicates
  3994 
  3995   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  3996 
  3997     inductive
  3998       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3999       for z_1 :: U_1 and ... and z_n :: U_m
  4000     where
  4001       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4002     | ...
  4003 
  4004   with full support for type-inference, rather than
  4005 
  4006     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4007 
  4008     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4009     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4010 
  4011     inductive "s z_1 ... z_m"
  4012     intros
  4013       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4014       ...
  4015 
  4016   For backward compatibility, there is a wrapper allowing inductive
  4017   sets to be defined with the new package via
  4018 
  4019     inductive_set
  4020       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4021       for z_1 :: U_1 and ... and z_n :: U_m
  4022     where
  4023       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4024     | ...
  4025 
  4026   or
  4027 
  4028     inductive_set
  4029       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4030       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4031       for z_1 :: U_1 and ... and z_n :: U_m
  4032     where
  4033       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4034     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4035     | ...
  4036 
  4037   if the additional syntax "p ..." is required.
  4038 
  4039   Numerous examples can be found in the subdirectories src/HOL/Auth,
  4040   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  4041 
  4042   INCOMPATIBILITIES:
  4043 
  4044   - Since declaration and definition of inductive sets or predicates
  4045     is no longer separated, abbreviations involving the newly
  4046     introduced sets or predicates must be specified together with the
  4047     introduction rules after the 'where' keyword (see above), rather
  4048     than before the actual inductive definition.
  4049 
  4050   - The variables in induction and elimination rules are now
  4051     quantified in the order of their occurrence in the introduction
  4052     rules, rather than in alphabetical order. Since this may break
  4053     some proofs, these proofs either have to be repaired, e.g. by
  4054     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  4055     statements of the form
  4056 
  4057       case (rule_i a_i_1 ... a_i_{k_i})
  4058 
  4059     or the old order of quantification has to be restored by explicitly adding
  4060     meta-level quantifiers in the introduction rules, i.e.
  4061 
  4062       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  4063 
  4064   - The format of the elimination rules is now
  4065 
  4066       p z_1 ... z_m x_1 ... x_n ==>
  4067         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4068         ==> ... ==> P
  4069 
  4070     for predicates and
  4071 
  4072       (x_1, ..., x_n) : s z_1 ... z_m ==>
  4073         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4074         ==> ... ==> P
  4075 
  4076     for sets rather than
  4077 
  4078       x : s z_1 ... z_m ==>
  4079         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  4080         ==> ... ==> P
  4081 
  4082     This may require terms in goals to be expanded to n-tuples
  4083     (e.g. using case_tac or simplification with the split_paired_all
  4084     rule) before the above elimination rule is applicable.
  4085 
  4086   - The elimination or case analysis rules for (mutually) inductive
  4087     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  4088     list of rules "p_1_..._p_k.elims" is no longer available.
  4089 
  4090 * New package "function"/"fun" for general recursive functions,
  4091 supporting mutual and nested recursion, definitions in local contexts,
  4092 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  4093 for small examples, and the separate tutorial on the function
  4094 package. The old recdef "package" is still available as before, but
  4095 users are encouraged to use the new package.
  4096 
  4097 * Method "lexicographic_order" automatically synthesizes termination
  4098 relations as lexicographic combinations of size measures. 
  4099 
  4100 * Case-expressions allow arbitrary constructor-patterns (including
  4101 "_") and take their order into account, like in functional
  4102 programming.  Internally, this is translated into nested
  4103 case-expressions; missing cases are added and mapped to the predefined
  4104 constant "undefined". In complicated cases printing may no longer show
  4105 the original input but the internal form. Lambda-abstractions allow
  4106 the same form of pattern matching: "% pat1 => e1 | ..." is an
  4107 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  4108 variable.
  4109 
  4110 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  4111 is an abbreviation for "of_nat :: nat => int". The simplification
  4112 rules for "of_nat" have been changed to work like "int" did
  4113 previously.  Potential INCOMPATIBILITY:
  4114   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  4115   - of_nat_diff and of_nat_mult are no longer default simp rules
  4116 
  4117 * Method "algebra" solves polynomial equations over (semi)rings using
  4118 Groebner bases. The (semi)ring structure is defined by locales and the
  4119 tool setup depends on that generic context. Installing the method for
  4120 a specific type involves instantiating the locale and possibly adding
  4121 declarations for computation on the coefficients.  The method is
  4122 already instantiated for natural numbers and for the axiomatic class
  4123 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  4124 CALCULEMUS 2007 for the general principles underlying this
  4125 architecture of context-aware proof-tools.
  4126 
  4127 * Method "ferrack" implements quantifier elimination over
  4128 special-purpose dense linear orders using locales (analogous to
  4129 "algebra"). The method is already installed for class
  4130 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  4131 rat, etc.
  4132 
  4133 * Former constant "List.op @" now named "List.append".  Use ML
  4134 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  4135 circumvent possible incompatibilities when working on ML level.
  4136 
  4137 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  4138 
  4139 * New function listsum :: 'a list => 'a for arbitrary monoids.
  4140 Special syntax: "SUM x <- xs. f x" (and latex variants)
  4141 
  4142 * New syntax for Haskell-like list comprehension (input only), eg.
  4143 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  4144 
  4145 * The special syntax for function "filter" has changed from [x :
  4146 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  4147 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  4148 
  4149 * [a..b] is now defined for arbitrary linear orders.  It used to be
  4150 defined on nat only, as an abbreviation for [a..<Suc b]
  4151 INCOMPATIBILITY.
  4152 
  4153 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  4154 
  4155 * New functions "sorted" and "sort" in src/HOL/List.thy.
  4156 
  4157 * New lemma collection field_simps (an extension of ring_simps) for
  4158 manipulating (in)equations involving division. Multiplies with all
  4159 denominators that can be proved to be non-zero (in equations) or
  4160 positive/negative (in inequations).
  4161 
  4162 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  4163 have been improved and renamed to ring_simps, group_simps and
  4164 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  4165 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  4166 
  4167 * Theory Library/Commutative_Ring: switched from recdef to function
  4168 package; constants add, mul, pow now curried.  Infix syntax for
  4169 algebraic operations.
  4170 
  4171 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  4172 INCOMPATIBILITY.
  4173 
  4174 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  4175 INCOMPATIBILITY.
  4176 
  4177 * HOL/records: generalised field-update to take a function on the
  4178 field rather than the new value: r(|A := x|) is translated to A_update
  4179 (K x) r The K-combinator that is internally used is called K_record.
  4180 INCOMPATIBILITY: Usage of the plain update functions has to be
  4181 adapted.
  4182  
  4183 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  4184 * x = 0, which are required for a semiring.  Richer structures do not
  4185 inherit from semiring_0 anymore, because this property is a theorem
  4186 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  4187 there is more to prove, but this is mostly trivial.
  4188 
  4189 * Class "recpower" is generalized to arbitrary monoids, not just
  4190 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  4191 commutativity or semiring properties additionally.
  4192 
  4193 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  4194 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  4195 better use 'abbreviation'.
  4196 
  4197 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  4198 
  4199 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  4200 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  4201 significant changes for setting up numeral syntax for types:
  4202   - New constants Numeral.pred and Numeral.succ instead
  4203       of former Numeral.bin_pred and Numeral.bin_succ.
  4204   - Use integer operations instead of bin_add, bin_mult and so on.
  4205   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  4206   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  4207 
  4208 See src/HOL/Integ/IntArith.thy for an example setup.
  4209 
  4210 * Command 'normal_form' computes the normal form of a term that may
  4211 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  4212 produces ``[b, c, a]'' (without proof).  This command is suitable for
  4213 heavy-duty computations because the functions are compiled to ML
  4214 first.  Correspondingly, a method "normalization" is provided.  See
  4215 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  4216 
  4217 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  4218 25 like -->); output depends on the "iff" print_mode, the default is
  4219 "A = B" (with priority 50).
  4220 
  4221 * Relations less (<) and less_eq (<=) are also available on type bool.
  4222 Modified syntax to disallow nesting without explicit parentheses,
  4223 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  4224 INCOMPATIBILITY.
  4225 
  4226 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  4227 
  4228 * Relation composition operator "op O" now has precedence 75 and binds
  4229 stronger than union and intersection. INCOMPATIBILITY.
  4230 
  4231 * The old set interval syntax "{m..n(}" (and relatives) has been
  4232 removed.  Use "{m..<n}" (and relatives) instead.
  4233 
  4234 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  4235 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  4236 ``declare [[simproc del: neq]]''.
  4237 
  4238 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  4239 True/False.
  4240 
  4241 * Theorem Cons_eq_map_conv no longer declared as "simp".
  4242 
  4243 * Theorem setsum_mult renamed to setsum_right_distrib.
  4244 
  4245 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  4246 ``rule'' method.
  4247 
  4248 * Reimplemented methods "sat" and "satx", with several improvements:
  4249 goals no longer need to be stated as "<prems> ==> False", equivalences
  4250 (i.e. "=" on type bool) are handled, variable names of the form
  4251 "lit_<n>" are no longer reserved, significant speedup.
  4252 
  4253 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  4254 zChaff is still supported as well.
  4255 
  4256 * 'inductive' and 'datatype': provide projections of mutual rules,
  4257 bundled as foo_bar.inducts;
  4258 
  4259 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  4260 Library.
  4261 
  4262 * Library: moved theory Accessible_Part to main HOL.
  4263 
  4264 * Library: added theory Coinductive_List of potentially infinite lists
  4265 as greatest fixed-point.
  4266 
  4267 * Library: added theory AssocList which implements (finite) maps as
  4268 association lists.
  4269 
  4270 * Method "evaluation" solves goals (i.e. a boolean expression)
  4271 efficiently by compiling it to ML.  The goal is "proved" (via an
  4272 oracle) if it evaluates to True.
  4273 
  4274 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  4275 also when invoked by the simplifier.  This results in the Simplifier
  4276 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  4277 Configuration option fast_arith_split_limit=0 recovers the old
  4278 behavior.
  4279 
  4280 * Support for hex (0x20) and binary (0b1001) numerals.
  4281 
  4282 * New method: reify eqs (t), where eqs are equations for an
  4283 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  4284 parameter, computes a term s::'b and a list xs::'a list and proves the
  4285 theorem I xs s = t. This is also known as reification or quoting. The
  4286 resulting theorem is applied to the subgoal to substitute t with I xs
  4287 s.  If t is omitted, the subgoal itself is reified.
  4288 
  4289 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  4290 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  4291 where f is supposed to be a computable function (in the sense of code
  4292 generattion). The method uses reify to compute s and xs as above then
  4293 applies corr_thm and uses normalization by evaluation to "prove" f s =
  4294 r and finally gets the theorem t = r, which is again applied to the
  4295 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  4296 
  4297 * Reflection: Automatic reification now handels binding, an example is
  4298 available in src/HOL/ex/ReflectionEx.thy
  4299 
  4300 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  4301 command 'statespace' that is similar to 'record', but introduces an
  4302 abstract specification based on the locale infrastructure instead of
  4303 HOL types.  This leads to extra flexibility in composing state spaces,
  4304 in particular multiple inheritance and renaming of components.
  4305 
  4306 
  4307 *** HOL-Complex ***
  4308 
  4309 * Hyperreal: Functions root and sqrt are now defined on negative real
  4310 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  4311 Nonnegativity side conditions have been removed from many lemmas, so
  4312 that more subgoals may now be solved by simplification; potential
  4313 INCOMPATIBILITY.
  4314 
  4315 * Real: new type classes formalize real normed vector spaces and
  4316 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  4317 and norm :: 'a => real.
  4318 
  4319 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  4320 reals into other types. The overloaded constant Reals :: 'a set is now
  4321 defined as range of_real; potential INCOMPATIBILITY.
  4322 
  4323 * Real: proper support for ML code generation, including 'quickcheck'.
  4324 Reals are implemented as arbitrary precision rationals.
  4325 
  4326 * Hyperreal: Several constants that previously worked only for the
  4327 reals have been generalized, so they now work over arbitrary vector
  4328 spaces. Type annotations may need to be added in some cases; potential
  4329 INCOMPATIBILITY.
  4330 
  4331   Infinitesimal  :: ('a::real_normed_vector) star set
  4332   HFinite        :: ('a::real_normed_vector) star set
  4333   HInfinite      :: ('a::real_normed_vector) star set
  4334   approx         :: ('a::real_normed_vector) star => 'a star => bool
  4335   monad          :: ('a::real_normed_vector) star => 'a star set
  4336   galaxy         :: ('a::real_normed_vector) star => 'a star set
  4337   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  4338   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  4339   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  4340   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  4341   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  4342   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  4343   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  4344   sgn            :: 'a::real_normed_vector => 'a
  4345   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  4346 
  4347 * Complex: Some complex-specific constants are now abbreviations for
  4348 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  4349 hnorm.  Other constants have been entirely removed in favor of the
  4350 polymorphic versions (INCOMPATIBILITY):
  4351 
  4352   approx        <-- capprox
  4353   HFinite       <-- CFinite
  4354   HInfinite     <-- CInfinite
  4355   Infinitesimal <-- CInfinitesimal
  4356   monad         <-- cmonad
  4357   galaxy        <-- cgalaxy
  4358   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  4359   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  4360   (ns)deriv     <-- (ns)cderiv
  4361 
  4362 
  4363 *** HOL-Algebra ***
  4364 
  4365 * Formalisation of ideals and the quotient construction over rings.
  4366 
  4367 * Order and lattice theory no longer based on records.
  4368 INCOMPATIBILITY.
  4369 
  4370 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  4371 greatest_closed.  INCOMPATIBILITY.
  4372 
  4373 * Method algebra is now set up via an attribute.  For examples see
  4374 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  4375 of algebraic structures.
  4376 
  4377 * Renamed theory CRing to Ring.
  4378 
  4379 
  4380 *** HOL-Nominal ***
  4381 
  4382 * Substantial, yet incomplete support for nominal datatypes (binding
  4383 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  4384 src/HOL/Nominal/Examples.  Prospective users should consult
  4385 http://isabelle.in.tum.de/nominal/
  4386 
  4387 
  4388 *** ML ***
  4389 
  4390 * ML basics: just one true type int, which coincides with IntInf.int
  4391 (even on SML/NJ).
  4392 
  4393 * ML within Isar: antiquotations allow to embed statically-checked
  4394 formal entities in the source, referring to the context available at
  4395 compile-time.  For example:
  4396 
  4397 ML {* @{sort "{zero,one}"} *}
  4398 ML {* @{typ "'a => 'b"} *}
  4399 ML {* @{term "%x. x"} *}
  4400 ML {* @{prop "x == y"} *}
  4401 ML {* @{ctyp "'a => 'b"} *}
  4402 ML {* @{cterm "%x. x"} *}
  4403 ML {* @{cprop "x == y"} *}
  4404 ML {* @{thm asm_rl} *}
  4405 ML {* @{thms asm_rl} *}
  4406 ML {* @{type_name c} *}
  4407 ML {* @{type_syntax c} *}
  4408 ML {* @{const_name c} *}
  4409 ML {* @{const_syntax c} *}
  4410 ML {* @{context} *}
  4411 ML {* @{theory} *}
  4412 ML {* @{theory Pure} *}
  4413 ML {* @{theory_ref} *}
  4414 ML {* @{theory_ref Pure} *}
  4415 ML {* @{simpset} *}
  4416 ML {* @{claset} *}
  4417 ML {* @{clasimpset} *}
  4418 
  4419 The same works for sources being ``used'' within an Isar context.
  4420 
  4421 * ML in Isar: improved error reporting; extra verbosity with
  4422 ML_Context.trace enabled.
  4423 
  4424 * Pure/General/table.ML: the join operations now works via exceptions
  4425 DUP/SAME instead of type option. This is simpler in simple cases, and
  4426 admits slightly more efficient complex applications.
  4427 
  4428 * Pure: 'advanced' translation functions (parse_translation etc.) now
  4429 use Context.generic instead of just theory.
  4430 
  4431 * Pure: datatype Context.generic joins theory/Proof.context and
  4432 provides some facilities for code that works in either kind of
  4433 context, notably GenericDataFun for uniform theory and proof data.
  4434 
  4435 * Pure: simplified internal attribute type, which is now always
  4436 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  4437 local (Proof.context) attributes have been discontinued, while
  4438 minimizing code duplication. Thm.rule_attribute and
  4439 Thm.declaration_attribute build canonical attributes; see also structure
  4440 Context for further operations on Context.generic, notably
  4441 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  4442 declarations and definitions.
  4443 
  4444 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  4445 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  4446 init only required for impure data. INCOMPATIBILITY: empty really need
  4447 to be empty (no dependencies on theory content!)
  4448 
  4449 * Pure/kernel: consts certification ignores sort constraints given in
  4450 signature declarations. (This information is not relevant to the
  4451 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  4452 potential INCOMPATIBILITY.
  4453 
  4454 * Pure: axiomatic type classes are now purely definitional, with
  4455 explicit proofs of class axioms and super class relations performed
  4456 internally. See Pure/axclass.ML for the main internal interfaces --
  4457 notably AxClass.define_class supercedes AxClass.add_axclass, and
  4458 AxClass.axiomatize_class/classrel/arity supersede
  4459 Sign.add_classes/classrel/arities.
  4460 
  4461 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  4462 global/local versions on theory vs. Proof.context have been
  4463 discontinued; Attrib.syntax and Method.syntax have been adapted
  4464 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  4465 attributes, methods, etc.
  4466 
  4467 * Pure: several functions of signature "... -> theory -> theory * ..."
  4468 have been reoriented to "... -> theory -> ... * theory" in order to
  4469 allow natural usage in combination with the ||>, ||>>, |-> and
  4470 fold_map combinators.
  4471 
  4472 * Pure: official theorem names (closed derivations) and additional
  4473 comments (tags) are now strictly separate.  Name hints -- which are
  4474 maintained as tags -- may be attached any time without affecting the
  4475 derivation.
  4476 
  4477 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  4478 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  4479 achieve the old behaviour.
  4480 
  4481 * Pure: the "Goal" constant is now called "prop", supporting a
  4482 slightly more general idea of ``protecting'' meta-level rule
  4483 statements.
  4484 
  4485 * Pure: Logic.(un)varify only works in a global context, which is now
  4486 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  4487 Logic.legacy_(un)varify as temporary workaround.
  4488 
  4489 * Pure: structure Name provides scalable operations for generating
  4490 internal variable names, notably Name.variants etc.  This replaces
  4491 some popular functions from term.ML:
  4492 
  4493   Term.variant		->  Name.variant
  4494   Term.variantlist	->  Name.variant_list
  4495   Term.invent_names	->  Name.invent_list
  4496 
  4497 Note that low-level renaming rarely occurs in new code -- operations
  4498 from structure Variable are used instead (see below).
  4499 
  4500 * Pure: structure Variable provides fundamental operations for proper
  4501 treatment of fixed/schematic variables in a context.  For example,
  4502 Variable.import introduces fixes for schematics of given facts and
  4503 Variable.export reverses the effect (up to renaming) -- this replaces
  4504 various freeze_thaw operations.
  4505 
  4506 * Pure: structure Goal provides simple interfaces for
  4507 init/conclude/finish and tactical prove operations (replacing former
  4508 Tactic.prove).  Goal.prove is the canonical way to prove results
  4509 within a given context; Goal.prove_global is a degraded version for
  4510 theory level goals, including a global Drule.standard.  Note that
  4511 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  4512 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  4513 in a locale context).
  4514 
  4515 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  4516 and type checking (Syntax.check_term etc.), with common combinations
  4517 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  4518 which are considered legacy and await removal.
  4519 
  4520 * Pure/Syntax: generic interfaces for type unchecking
  4521 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  4522 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  4523 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  4524 available for convenience, but refer to the very same operations using
  4525 a mere theory instead of a full context.
  4526 
  4527 * Isar: simplified treatment of user-level errors, using exception
  4528 ERROR of string uniformly.  Function error now merely raises ERROR,
  4529 without any side effect on output channels.  The Isar toplevel takes
  4530 care of proper display of ERROR exceptions.  ML code may use plain
  4531 handle/can/try; cat_error may be used to concatenate errors like this:
  4532 
  4533   ... handle ERROR msg => cat_error msg "..."
  4534 
  4535 Toplevel ML code (run directly or through the Isar toplevel) may be
  4536 embedded into the Isar toplevel with exception display/debug like
  4537 this:
  4538 
  4539   Isar.toplevel (fn () => ...)
  4540 
  4541 INCOMPATIBILITY, removed special transform_error facilities, removed
  4542 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  4543 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  4544 -- use plain ERROR instead.
  4545 
  4546 * Isar: theory setup now has type (theory -> theory), instead of a
  4547 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  4548 
  4549 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  4550 ProofContext.debug/verbose flags.
  4551 
  4552 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  4553 theory before entering a proof state.  Transactions now always see a
  4554 quasi-functional intermediate checkpoint, both in interactive and
  4555 batch mode.
  4556 
  4557 * Isar: simplified interfaces for outer syntax.  Renamed
  4558 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  4559 OuterSyntax.add_parsers -- this functionality is now included in
  4560 OuterSyntax.command etc.  INCOMPATIBILITY.
  4561 
  4562 * Simplifier: the simpset of a running simplification process now
  4563 contains a proof context (cf. Simplifier.the_context), which is the
  4564 very context that the initial simpset has been retrieved from (by
  4565 simpset_of/local_simpset_of).  Consequently, all plug-in components
  4566 (solver, looper etc.) may depend on arbitrary proof data.
  4567 
  4568 * Simplifier.inherit_context inherits the proof context (plus the
  4569 local bounds) of the current simplification process; any simproc
  4570 etc. that calls the Simplifier recursively should do this!  Removed
  4571 former Simplifier.inherit_bounds, which is already included here --
  4572 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  4573 specify an explicit context using Simplifier.context/theory_context.
  4574 
  4575 * Simplifier/Classical Reasoner: more abstract interfaces
  4576 change_simpset/claset for modifying the simpset/claset reference of a
  4577 theory; raw versions simpset/claset_ref etc. have been discontinued --
  4578 INCOMPATIBILITY.
  4579 
  4580 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  4581 "Trueprop" etc.
  4582 
  4583 
  4584 *** System ***
  4585 
  4586 * settings: the default heap location within ISABELLE_HOME_USER now
  4587 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  4588 Isabelle installations.
  4589 
  4590 * isabelle-process: option -S (secure mode) disables some critical
  4591 operations, notably runtime compilation and evaluation of ML source
  4592 code.
  4593 
  4594 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  4595 
  4596 * Support for parallel execution, using native multicore support of
  4597 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  4598 independent theories, according to the given theory header
  4599 specifications. The maximum number of worker threads is specified via
  4600 usedir option -M or the "max-threads" setting in Proof General. A
  4601 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  4602 to 6 on a 8-core machine.  User-code needs to observe certain
  4603 guidelines for thread-safe programming, see appendix A in the Isar
  4604 Implementation manual.
  4605 
  4606 
  4607 
  4608 New in Isabelle2005 (October 2005)
  4609 ----------------------------------
  4610 
  4611 *** General ***
  4612 
  4613 * Theory headers: the new header syntax for Isar theories is
  4614 
  4615   theory <name>
  4616   imports <theory1> ... <theoryN>
  4617   uses <file1> ... <fileM>
  4618   begin
  4619 
  4620 where the 'uses' part is optional.  The previous syntax
  4621 
  4622   theory <name> = <theory1> + ... + <theoryN>:
  4623 
  4624 will disappear in the next release.  Use isatool fixheaders to convert
  4625 existing theory files.  Note that there is no change in ancient
  4626 non-Isar theories now, but these will disappear soon.
  4627 
  4628 * Theory loader: parent theories can now also be referred to via
  4629 relative and absolute paths.
  4630 
  4631 * Command 'find_theorems' searches for a list of criteria instead of a
  4632 list of constants. Known criteria are: intro, elim, dest, name:string,
  4633 simp:term, and any term. Criteria can be preceded by '-' to select
  4634 theorems that do not match. Intro, elim, dest select theorems that
  4635 match the current goal, name:s selects theorems whose fully qualified
  4636 name contain s, and simp:term selects all simplification rules whose
  4637 lhs match term.  Any other term is interpreted as pattern and selects
  4638 all theorems matching the pattern. Available in ProofGeneral under
  4639 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  4640 
  4641   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  4642 
  4643 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  4644 matching the current goal as introduction rule and not having "HOL."
  4645 in their name (i.e. not being defined in theory HOL).
  4646 
  4647 * Command 'thms_containing' has been discontinued in favour of
  4648 'find_theorems'; INCOMPATIBILITY.
  4649 
  4650 * Communication with Proof General is now 8bit clean, which means that
  4651 Unicode text in UTF-8 encoding may be used within theory texts (both
  4652 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4653 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4654 
  4655   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4656   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4657 
  4658 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4659 Classical Reasoner.  Typical big applications run around 2 times
  4660 faster.
  4661 
  4662 
  4663 *** Document preparation ***
  4664 
  4665 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4666 of raw sources.  Only those symbols that do not require additional
  4667 LaTeX packages (depending on comments in isabellesym.sty) are
  4668 displayed properly, everything else is left verbatim.  isatool display
  4669 and isatool print are used as front ends (these are subject to the
  4670 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4671 
  4672 * Command tags control specific markup of certain regions of text,
  4673 notably folding and hiding.  Predefined tags include "theory" (for
  4674 theory begin and end), "proof" for proof commands, and "ML" for
  4675 commands involving ML code; the additional tags "visible" and
  4676 "invisible" are unused by default.  Users may give explicit tag
  4677 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4678 interpretation of tags is determined by the LaTeX job during document
  4679 preparation: see option -V of isatool usedir, or options -n and -t of
  4680 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4681 \isadroptag.
  4682 
  4683 Several document versions may be produced at the same time via isatool
  4684 usedir (the generated index.html will link all of them).  Typical
  4685 specifications include ''-V document=theory,proof,ML'' to present
  4686 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4687 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4688 these parts without any formal replacement text.  The Isabelle site
  4689 default settings produce ''document'' and ''outline'' versions as
  4690 specified above.
  4691 
  4692 * Several new antiquotations:
  4693 
  4694   @{term_type term} prints a term with its type annotated;
  4695 
  4696   @{typeof term} prints the type of a term;
  4697 
  4698   @{const const} is the same as @{term const}, but checks that the
  4699   argument is a known logical constant;
  4700 
  4701   @{term_style style term} and @{thm_style style thm} print a term or
  4702   theorem applying a "style" to it
  4703 
  4704   @{ML text}
  4705 
  4706 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4707 definitions, equations, inequations etc., 'concl' printing only the
  4708 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4709 to print the specified premise.  TermStyle.add_style provides an ML
  4710 interface for introducing further styles.  See also the "LaTeX Sugar"
  4711 document practical applications.  The ML antiquotation prints
  4712 type-checked ML expressions verbatim.
  4713 
  4714 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4715 and 'text' support optional locale specification '(in loc)', which
  4716 specifies the default context for interpreting antiquotations.  For
  4717 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4718 
  4719 * Option 'locale=NAME' of antiquotations specifies an alternative
  4720 context interpreting the subsequent argument.  For example: @{thm
  4721 [locale=lattice] inf_assoc}.
  4722 
  4723 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4724 a proof context.
  4725 
  4726 * Proper output of antiquotations for theory commands involving a
  4727 proof context (such as 'locale' or 'theorem (in loc) ...').
  4728 
  4729 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4730 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4731 
  4732 * isatool usedir: new option -C (default true) controls whether option
  4733 -D should include a copy of the original document directory; -C false
  4734 prevents unwanted effects such as copying of administrative CVS data.
  4735 
  4736 
  4737 *** Pure ***
  4738 
  4739 * Considerably improved version of 'constdefs' command.  Now performs
  4740 automatic type-inference of declared constants; additional support for
  4741 local structure declarations (cf. locales and HOL records), see also
  4742 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4743 sequential dependencies of definitions within a single 'constdefs'
  4744 section; moreover, the declared name needs to be an identifier.  If
  4745 all fails, consider to fall back on 'consts' and 'defs' separately.
  4746 
  4747 * Improved indexed syntax and implicit structures.  First of all,
  4748 indexed syntax provides a notational device for subscripted
  4749 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4750 expressions.  Secondly, in a local context with structure
  4751 declarations, number indexes \<^sub>n or the empty index (default
  4752 number 1) refer to a certain fixed variable implicitly; option
  4753 show_structs controls printing of implicit structures.  Typical
  4754 applications of these concepts involve record types and locales.
  4755 
  4756 * New command 'no_syntax' removes grammar declarations (and
  4757 translations) resulting from the given syntax specification, which is
  4758 interpreted in the same manner as for the 'syntax' command.
  4759 
  4760 * 'Advanced' translation functions (parse_translation etc.) may depend
  4761 on the signature of the theory context being presently used for
  4762 parsing/printing, see also isar-ref manual.
  4763 
  4764 * Improved 'oracle' command provides a type-safe interface to turn an
  4765 ML expression of type theory -> T -> term into a primitive rule of
  4766 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4767 is already included here); see also FOL/ex/IffExample.thy;
  4768 INCOMPATIBILITY.
  4769 
  4770 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4771 before); "cI" is no longer bound, use "c.intro" instead.
  4772 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4773 axclasses vs. locales.
  4774 
  4775 * Improved internal renaming of symbolic identifiers -- attach primes
  4776 instead of base 26 numbers.
  4777 
  4778 * New flag show_question_marks controls printing of leading question
  4779 marks in schematic variable names.
  4780 
  4781 * In schematic variable names, *any* symbol following \<^isub> or
  4782 \<^isup> is now treated as part of the base name.  For example, the
  4783 following works without printing of awkward ".0" indexes:
  4784 
  4785   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4786     by simp
  4787 
  4788 * Inner syntax includes (*(*nested*) comments*).
  4789 
  4790 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4791 annotations as "(00...)".
  4792 
  4793 * Clear separation of logical types and nonterminals, where the latter
  4794 may only occur in 'syntax' specifications or type abbreviations.
  4795 Before that distinction was only partially implemented via type class
  4796 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4797 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4798 exotic syntax specifications may require further adaption
  4799 (e.g. Cube/Cube.thy).
  4800 
  4801 * Removed obsolete type class "logic", use the top sort {} instead.
  4802 Note that non-logical types should be declared as 'nonterminals'
  4803 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4804 specifications.
  4805 
  4806 * Attributes 'induct' and 'cases': type or set names may now be
  4807 locally fixed variables as well.
  4808 
  4809 * Simplifier: can now control the depth to which conditional rewriting
  4810 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4811 Limit.
  4812 
  4813 * Simplifier: simplification procedures may now take the current
  4814 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4815 interface), which is very useful for calling the Simplifier
  4816 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4817 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4818 low-level mk_simproc no longer applies Logic.varify internally, to
  4819 allow for use in a context of fixed variables.
  4820 
  4821 * thin_tac now works even if the assumption being deleted contains !!
  4822 or ==>.  More generally, erule now works even if the major premise of
  4823 the elimination rule contains !! or ==>.
  4824 
  4825 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4826 
  4827 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4828 from Pure, which contains all common declarations already.  Both
  4829 theories are defined via plain Isabelle/Isar .thy files.
  4830 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4831 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4832 use isatool fixcpure to adapt your theory and ML sources.
  4833 
  4834 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4835 selections of theorems in named facts via index ranges.
  4836 
  4837 * 'print_theorems': in theory mode, really print the difference
  4838 wrt. the last state (works for interactive theory development only),
  4839 in proof mode print all local facts (cf. 'print_facts');
  4840 
  4841 * 'hide': option '(open)' hides only base names.
  4842 
  4843 * More efficient treatment of intermediate checkpoints in interactive
  4844 theory development.
  4845 
  4846 * Code generator is now invoked via code_module (incremental code
  4847 generation) and code_library (modular code generation, ML structures
  4848 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4849 must be quoted when used as identifiers.
  4850 
  4851 * New 'value' command for reading, evaluating and printing terms using
  4852 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4853 quoted when used as identifier.
  4854 
  4855 
  4856 *** Locales ***
  4857 
  4858 * New commands for the interpretation of locale expressions in
  4859 theories (1), locales (2) and proof contexts (3).  These generate
  4860 proof obligations from the expression specification.  After the
  4861 obligations have been discharged, theorems of the expression are added
  4862 to the theory, target locale or proof context.  The synopsis of the
  4863 commands is a follows:
  4864 
  4865   (1) interpretation expr inst
  4866   (2) interpretation target < expr
  4867   (3) interpret expr inst
  4868 
  4869 Interpretation in theories and proof contexts require a parameter
  4870 instantiation of terms from the current context.  This is applied to
  4871 specifications and theorems of the interpreted expression.
  4872 Interpretation in locales only permits parameter renaming through the
  4873 locale expression.  Interpretation is smart in that interpretations
  4874 that are active already do not occur in proof obligations, neither are
  4875 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4876 inspect active interpretations of a particular locale.  For details,
  4877 see the Isar Reference manual.  Examples can be found in
  4878 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4879 
  4880 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4881 'interpret' instead.
  4882 
  4883 * New context element 'constrains' for adding type constraints to
  4884 parameters.
  4885 
  4886 * Context expressions: renaming of parameters with syntax
  4887 redeclaration.
  4888 
  4889 * Locale declaration: 'includes' disallowed.
  4890 
  4891 * Proper static binding of attribute syntax -- i.e. types / terms /
  4892 facts mentioned as arguments are always those of the locale definition
  4893 context, independently of the context of later invocations.  Moreover,
  4894 locale operations (renaming and type / term instantiation) are applied
  4895 to attribute arguments as expected.
  4896 
  4897 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4898 actual attributes; rare situations may require Attrib.attribute to
  4899 embed those attributes into Attrib.src that lack concrete syntax.
  4900 Attribute implementations need to cooperate properly with the static
  4901 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4902 Attrib.XXX_thm etc. already do the right thing without further
  4903 intervention.  Only unusual applications -- such as "where" or "of"
  4904 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4905 on the context and the facts involved -- may have to assign parsed
  4906 values to argument tokens explicitly.
  4907 
  4908 * Changed parameter management in theorem generation for long goal
  4909 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4910 theorem statement in rare situations.
  4911 
  4912 * Locale inspection command 'print_locale' omits notes elements.  Use
  4913 'print_locale!' to have them included in the output.
  4914 
  4915 
  4916 *** Provers ***
  4917 
  4918 * Provers/hypsubst.ML: improved version of the subst method, for
  4919 single-step rewriting: it now works in bound variable contexts. New is
  4920 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  4921 rewrite a different subterm than the original subst method, which is
  4922 still available as 'simplesubst'.
  4923 
  4924 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  4925 and quasi orders.
  4926 
  4927 * Provers/trancl.ML: new transitivity reasoner for transitive and
  4928 reflexive-transitive closure of relations.
  4929 
  4930 * Provers/blast.ML: new reference depth_limit to make blast's depth
  4931 limit (previously hard-coded with a value of 20) user-definable.
  4932 
  4933 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  4934 is peformed already.  Object-logics merely need to finish their
  4935 initial simpset configuration as before.  INCOMPATIBILITY.
  4936 
  4937 
  4938 *** HOL ***
  4939 
  4940 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  4941 
  4942   syntax (epsilon)
  4943     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  4944 
  4945 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  4946 and x-symbol; use option '-m epsilon' to get it actually printed.
  4947 Moreover, the mathematically important symbolic identifier \<epsilon>
  4948 becomes available as variable, constant etc.  INCOMPATIBILITY,
  4949 
  4950 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  4951 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  4952 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  4953 support corresponding Isar calculations.
  4954 
  4955 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  4956 instead of ":".
  4957 
  4958 * theory SetInterval: changed the syntax for open intervals:
  4959 
  4960   Old       New
  4961   {..n(}    {..<n}
  4962   {)n..}    {n<..}
  4963   {m..n(}   {m..<n}
  4964   {)m..n}   {m<..n}
  4965   {)m..n(}  {m<..<n}
  4966 
  4967 The old syntax is still supported but will disappear in the next
  4968 release.  For conversion use the following Emacs search and replace
  4969 patterns (these are not perfect but work quite well):
  4970 
  4971   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  4972   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  4973 
  4974 * Theory Commutative_Ring (in Library): method comm_ring for proving
  4975 equalities in commutative rings; method 'algebra' provides a generic
  4976 interface.
  4977 
  4978 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  4979 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  4980 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  4981 be a tuple pattern.
  4982 
  4983 Some new syntax forms are available:
  4984 
  4985   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  4986   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  4987   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  4988   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  4989 
  4990 The latter form "\<Sum>x < k. e" used to be based on a separate
  4991 function "Summation", which has been discontinued.
  4992 
  4993 * theory Finite_Set: in structured induction proofs, the insert case
  4994 is now 'case (insert x F)' instead of the old counterintuitive 'case
  4995 (insert F x)'.
  4996 
  4997 * The 'refute' command has been extended to support a much larger
  4998 fragment of HOL, including axiomatic type classes, constdefs and
  4999 typedefs, inductive datatypes and recursion.
  5000 
  5001 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  5002 Requires zChaff with proof generation to be installed.  See
  5003 HOL/ex/SAT_Examples.thy for examples.
  5004 
  5005 * Datatype induction via method 'induct' now preserves the name of the
  5006 induction variable. For example, when proving P(xs::'a list) by
  5007 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  5008 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  5009 in unstructured proof scripts.
  5010 
  5011 * Reworked implementation of records.  Improved scalability for
  5012 records with many fields, avoiding performance problems for type
  5013 inference. Records are no longer composed of nested field types, but
  5014 of nested extension types. Therefore the record type only grows linear
  5015 in the number of extensions and not in the number of fields.  The
  5016 top-level (users) view on records is preserved.  Potential
  5017 INCOMPATIBILITY only in strange cases, where the theory depends on the
  5018 old record representation. The type generated for a record is called
  5019 <record_name>_ext_type.
  5020 
  5021 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  5022 proofs triggered by a record definition or a simproc (if
  5023 quick_and_dirty is enabled).  Definitions of large records can take
  5024 quite long.
  5025 
  5026 New simproc record_upd_simproc for simplification of multiple record
  5027 updates enabled by default.  Moreover, trivial updates are also
  5028 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  5029 occasionally, since simplification is more powerful by default.
  5030 
  5031 * typedef: proper support for polymorphic sets, which contain extra
  5032 type-variables in the term.
  5033 
  5034 * Simplifier: automatically reasons about transitivity chains
  5035 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  5036 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  5037 old proofs break occasionally as simplification may now solve more
  5038 goals than previously.
  5039 
  5040 * Simplifier: converts x <= y into x = y if assumption y <= x is
  5041 present.  Works for all partial orders (class "order"), in particular
  5042 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  5043 just like y <= x.
  5044 
  5045 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  5046 bound variable or a constant then the let is unfolded.  Otherwise
  5047 first a is simplified to b, and then f b is simplified to g. If
  5048 possible we abstract b from g arriving at "let x = b in h x",
  5049 otherwise we unfold the let and arrive at g.  The simproc can be
  5050 enabled/disabled by the reference use_let_simproc.  Potential
  5051 INCOMPATIBILITY since simplification is more powerful by default.
  5052 
  5053 * Classical reasoning: the meson method now accepts theorems as arguments.
  5054 
  5055 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  5056 jobs to provide advice on the provability of subgoals.
  5057 
  5058 * Theory OrderedGroup and Ring_and_Field: various additions and
  5059 improvements to faciliate calculations involving equalities and
  5060 inequalities.
  5061 
  5062 The following theorems have been eliminated or modified
  5063 (INCOMPATIBILITY):
  5064 
  5065   abs_eq             now named abs_of_nonneg
  5066   abs_of_ge_0        now named abs_of_nonneg
  5067   abs_minus_eq       now named abs_of_nonpos
  5068   imp_abs_id         now named abs_of_nonneg
  5069   imp_abs_neg_id     now named abs_of_nonpos
  5070   mult_pos           now named mult_pos_pos
  5071   mult_pos_le        now named mult_nonneg_nonneg
  5072   mult_pos_neg_le    now named mult_nonneg_nonpos
  5073   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  5074   mult_neg           now named mult_neg_neg
  5075   mult_neg_le        now named mult_nonpos_nonpos
  5076 
  5077 * The following lemmas in Ring_and_Field have been added to the simplifier:
  5078      
  5079      zero_le_square
  5080      not_square_less_zero 
  5081 
  5082   The following lemmas have been deleted from Real/RealPow:
  5083   
  5084      realpow_zero_zero
  5085      realpow_two
  5086      realpow_less
  5087      zero_le_power
  5088      realpow_two_le
  5089      abs_realpow_two
  5090      realpow_two_abs     
  5091 
  5092 * Theory Parity: added rules for simplifying exponents.
  5093 
  5094 * Theory List:
  5095 
  5096 The following theorems have been eliminated or modified
  5097 (INCOMPATIBILITY):
  5098 
  5099   list_all_Nil       now named list_all.simps(1)
  5100   list_all_Cons      now named list_all.simps(2)
  5101   list_all_conv      now named list_all_iff
  5102   set_mem_eq         now named mem_iff
  5103 
  5104 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  5105 asymptotic "big O" calculations.  See the notes in BigO.thy.
  5106 
  5107 
  5108 *** HOL-Complex ***
  5109 
  5110 * Theory RealDef: better support for embedding natural numbers and
  5111 integers in the reals.
  5112 
  5113 The following theorems have been eliminated or modified
  5114 (INCOMPATIBILITY):
  5115 
  5116   exp_ge_add_one_self  now requires no hypotheses
  5117   real_of_int_add      reversed direction of equality (use [symmetric])
  5118   real_of_int_minus    reversed direction of equality (use [symmetric])
  5119   real_of_int_diff     reversed direction of equality (use [symmetric])
  5120   real_of_int_mult     reversed direction of equality (use [symmetric])
  5121 
  5122 * Theory RComplete: expanded support for floor and ceiling functions.
  5123 
  5124 * Theory Ln is new, with properties of the natural logarithm
  5125 
  5126 * Hyperreal: There is a new type constructor "star" for making
  5127 nonstandard types.  The old type names are now type synonyms:
  5128 
  5129   hypreal = real star
  5130   hypnat = nat star
  5131   hcomplex = complex star
  5132 
  5133 * Hyperreal: Many groups of similarly-defined constants have been
  5134 replaced by polymorphic versions (INCOMPATIBILITY):
  5135 
  5136   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  5137 
  5138   starset      <-- starsetNat, starsetC
  5139   *s*          <-- *sNat*, *sc*
  5140   starset_n    <-- starsetNat_n, starsetC_n
  5141   *sn*         <-- *sNatn*, *scn*
  5142   InternalSets <-- InternalNatSets, InternalCSets
  5143 
  5144   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  5145   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  5146   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  5147   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  5148   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  5149 
  5150 * Hyperreal: Many type-specific theorems have been removed in favor of
  5151 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  5152 
  5153   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  5154   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  5155   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  5156   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  5157   right_minus <-- hypreal_add_minus
  5158   left_minus <-- {hypreal,hcomplex}_add_minus_left
  5159   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  5160   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  5161   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  5162   mult_1_right <-- hcomplex_mult_one_right
  5163   mult_zero_left <-- hcomplex_mult_zero_left
  5164   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  5165   right_distrib <-- hypnat_add_mult_distrib2
  5166   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  5167   right_inverse <-- hypreal_mult_inverse
  5168   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  5169   order_refl <-- {hypreal,hypnat}_le_refl
  5170   order_trans <-- {hypreal,hypnat}_le_trans
  5171   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  5172   order_less_le <-- {hypreal,hypnat}_less_le
  5173   linorder_linear <-- {hypreal,hypnat}_le_linear
  5174   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  5175   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  5176   add_nonneg_nonneg <-- hypreal_le_add_order
  5177 
  5178 * Hyperreal: Separate theorems having to do with type-specific
  5179 versions of constants have been merged into theorems that apply to the
  5180 new polymorphic constants (INCOMPATIBILITY):
  5181 
  5182   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  5183   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  5184   STAR_Un <-- {STAR,NatStar,STARC}_Un
  5185   STAR_Int <-- {STAR,NatStar,STARC}_Int
  5186   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  5187   STAR_subset <-- {STAR,NatStar,STARC}_subset
  5188   STAR_mem <-- {STAR,NatStar,STARC}_mem
  5189   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  5190   STAR_diff <-- {STAR,STARC}_diff
  5191   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  5192     STARC_hcomplex_of_complex}_image_subset
  5193   starset_n_Un <-- starset{Nat,C}_n_Un
  5194   starset_n_Int <-- starset{Nat,C}_n_Int
  5195   starset_n_Compl <-- starset{Nat,C}_n_Compl
  5196   starset_n_diff <-- starset{Nat,C}_n_diff
  5197   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  5198   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  5199   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  5200   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  5201   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  5202   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  5203   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  5204   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  5205   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  5206   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  5207   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  5208   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  5209   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  5210   starfun_diff <-- starfun{C,RC,CR}_diff
  5211   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  5212   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  5213   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  5214   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  5215   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  5216   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  5217   starfun_Id <-- starfunC_Id
  5218   starfun_approx <-- starfun{Nat,CR}_approx
  5219   starfun_capprox <-- starfun{C,RC}_capprox
  5220   starfun_abs <-- starfunNat_rabs
  5221   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  5222   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  5223   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  5224   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  5225   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  5226   starfun_add_approx <-- starfunCR_add_approx
  5227   starfun_inverse_inverse <-- starfunC_inverse_inverse
  5228   starfun_divide <-- starfun{C,CR,RC}_divide
  5229   starfun_n <-- starfun{Nat,C}_n
  5230   starfun_n_mult <-- starfun{Nat,C}_n_mult
  5231   starfun_n_add <-- starfun{Nat,C}_n_add
  5232   starfun_n_add_minus <-- starfunNat_n_add_minus
  5233   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  5234   starfun_n_minus <-- starfun{Nat,C}_n_minus
  5235   starfun_n_eq <-- starfun{Nat,C}_n_eq
  5236 
  5237   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  5238   star_n_minus <-- {hypreal,hcomplex}_minus
  5239   star_n_diff <-- {hypreal,hcomplex}_diff
  5240   star_n_mult <-- {hypreal,hcomplex}_mult
  5241   star_n_inverse <-- {hypreal,hcomplex}_inverse
  5242   star_n_le <-- {hypreal,hypnat}_le
  5243   star_n_less <-- {hypreal,hypnat}_less
  5244   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  5245   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  5246   star_n_abs <-- hypreal_hrabs
  5247   star_n_divide <-- hcomplex_divide
  5248 
  5249   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  5250   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  5251   star_of_diff <-- hypreal_of_real_diff
  5252   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  5253   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  5254   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  5255   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  5256   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  5257   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  5258   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  5259   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  5260   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  5261   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  5262   star_of_number_of <-- {hypreal,hcomplex}_number_of
  5263   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  5264   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  5265   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  5266   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  5267   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  5268   star_of_power <-- hypreal_of_real_power
  5269   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  5270 
  5271 * Hyperreal: new method "transfer" that implements the transfer
  5272 principle of nonstandard analysis. With a subgoal that mentions
  5273 nonstandard types like "'a star", the command "apply transfer"
  5274 replaces it with an equivalent one that mentions only standard types.
  5275 To be successful, all free variables must have standard types; non-
  5276 standard variables must have explicit universal quantifiers.
  5277 
  5278 * Hyperreal: A theory of Taylor series.
  5279 
  5280 
  5281 *** HOLCF ***
  5282 
  5283 * Discontinued special version of 'constdefs' (which used to support
  5284 continuous functions) in favor of the general Pure one with full
  5285 type-inference.
  5286 
  5287 * New simplification procedure for solving continuity conditions; it
  5288 is much faster on terms with many nested lambda abstractions (cubic
  5289 instead of exponential time).
  5290 
  5291 * New syntax for domain package: selector names are now optional.
  5292 Parentheses should be omitted unless argument is lazy, for example:
  5293 
  5294   domain 'a stream = cons "'a" (lazy "'a stream")
  5295 
  5296 * New command 'fixrec' for defining recursive functions with pattern
  5297 matching; defining multiple functions with mutual recursion is also
  5298 supported.  Patterns may include the constants cpair, spair, up, sinl,
  5299 sinr, or any data constructor defined by the domain package. The given
  5300 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  5301 syntax and examples.
  5302 
  5303 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  5304 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  5305 but the proof obligation additionally includes an admissibility
  5306 requirement. The packages generate instances of class cpo or pcpo,
  5307 with continuity and strictness theorems for Rep and Abs.
  5308 
  5309 * HOLCF: Many theorems have been renamed according to a more standard naming
  5310 scheme (INCOMPATIBILITY):
  5311 
  5312   foo_inject:  "foo$x = foo$y ==> x = y"
  5313   foo_eq:      "(foo$x = foo$y) = (x = y)"
  5314   foo_less:    "(foo$x << foo$y) = (x << y)"
  5315   foo_strict:  "foo$UU = UU"
  5316   foo_defined: "... ==> foo$x ~= UU"
  5317   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  5318 
  5319 
  5320 *** ZF ***
  5321 
  5322 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  5323 including the First Isomorphism Theorem (on quotienting by the kernel
  5324 of a homomorphism).
  5325 
  5326 * ZF/Simplifier: install second copy of type solver that actually
  5327 makes use of TC rules declared to Isar proof contexts (or locales);
  5328 the old version is still required for ML proof scripts.
  5329 
  5330 
  5331 *** Cube ***
  5332 
  5333 * Converted to Isar theory format; use locales instead of axiomatic
  5334 theories.
  5335 
  5336 
  5337 *** ML ***
  5338 
  5339 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  5340 for ||>, ||>>, |>>,
  5341 
  5342 * Pure/library.ML no longer defines its own option datatype, but uses
  5343 that of the SML basis, which has constructors NONE and SOME instead of
  5344 None and Some, as well as exception Option.Option instead of OPTION.
  5345 The functions the, if_none, is_some, is_none have been adapted
  5346 accordingly, while Option.map replaces apsome.
  5347 
  5348 * Pure/library.ML: the exception LIST has been given up in favour of
  5349 the standard exceptions Empty and Subscript, as well as
  5350 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  5351 superceded by the standard hd and tl functions etc.
  5352 
  5353 A number of basic list functions are no longer exported to the ML
  5354 toplevel, as they are variants of predefined functions.  The following
  5355 suggests how one can translate existing code:
  5356 
  5357     rev_append xs ys = List.revAppend (xs, ys)
  5358     nth_elem (i, xs) = List.nth (xs, i)
  5359     last_elem xs = List.last xs
  5360     flat xss = List.concat xss
  5361     seq fs = List.app fs
  5362     partition P xs = List.partition P xs
  5363     mapfilter f xs = List.mapPartial f xs
  5364 
  5365 * Pure/library.ML: several combinators for linear functional
  5366 transformations, notably reverse application and composition:
  5367 
  5368   x |> f                f #> g
  5369   (x, y) |-> f          f #-> g
  5370 
  5371 * Pure/library.ML: introduced/changed precedence of infix operators:
  5372 
  5373   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  5374   infix 2 ?;
  5375   infix 3 o oo ooo oooo;
  5376   infix 4 ~~ upto downto;
  5377 
  5378 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  5379 infix operators.
  5380 
  5381 * Pure/library.ML: natural list combinators fold, fold_rev, and
  5382 fold_map support linear functional transformations and nesting.  For
  5383 example:
  5384 
  5385   fold f [x1, ..., xN] y =
  5386     y |> f x1 |> ... |> f xN
  5387 
  5388   (fold o fold) f [xs1, ..., xsN] y =
  5389     y |> fold f xs1 |> ... |> fold f xsN
  5390 
  5391   fold f [x1, ..., xN] =
  5392     f x1 #> ... #> f xN
  5393 
  5394   (fold o fold) f [xs1, ..., xsN] =
  5395     fold f xs1 #> ... #> fold f xsN
  5396 
  5397 * Pure/library.ML: the following selectors on type 'a option are
  5398 available:
  5399 
  5400   the:               'a option -> 'a  (*partial*)
  5401   these:             'a option -> 'a  where 'a = 'b list
  5402   the_default: 'a -> 'a option -> 'a
  5403   the_list:          'a option -> 'a list
  5404 
  5405 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5406 basic operations for association lists, following natural argument
  5407 order; moreover the explicit equality predicate passed here avoids
  5408 potentially expensive polymorphic runtime equality checks.
  5409 The old functions may be expressed as follows:
  5410 
  5411   assoc = uncurry (AList.lookup (op =))
  5412   assocs = these oo AList.lookup (op =)
  5413   overwrite = uncurry (AList.update (op =)) o swap
  5414 
  5415 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5416 
  5417   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  5418   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  5419 
  5420 replacing make_keylist and keyfilter (occassionally used)
  5421 Naive rewrites:
  5422 
  5423   make_keylist = AList.make
  5424   keyfilter = AList.find (op =)
  5425 
  5426 * eq_fst and eq_snd now take explicit equality parameter, thus
  5427   avoiding eqtypes. Naive rewrites:
  5428 
  5429     eq_fst = eq_fst (op =)
  5430     eq_snd = eq_snd (op =)
  5431 
  5432 * Removed deprecated apl and apr (rarely used).
  5433   Naive rewrites:
  5434 
  5435     apl (n, op) =>>= curry op n
  5436     apr (op, m) =>>= fn n => op (n, m)
  5437 
  5438 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  5439 provides a reasonably efficient light-weight implementation of sets as
  5440 lists.
  5441 
  5442 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  5443 few new operations; existing lookup and update are now curried to
  5444 follow natural argument order (for use with fold etc.);
  5445 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  5446 
  5447 * Pure/General: output via the Isabelle channels of
  5448 writeln/warning/error etc. is now passed through Output.output, with a
  5449 hook for arbitrary transformations depending on the print_mode
  5450 (cf. Output.add_mode -- the first active mode that provides a output
  5451 function wins).  Already formatted output may be embedded into further
  5452 text via Output.raw; the result of Pretty.string_of/str_of and derived
  5453 functions (string_of_term/cterm/thm etc.) is already marked raw to
  5454 accommodate easy composition of diagnostic messages etc.  Programmers
  5455 rarely need to care about Output.output or Output.raw at all, with
  5456 some notable exceptions: Output.output is required when bypassing the
  5457 standard channels (writeln etc.), or in token translations to produce
  5458 properly formatted results; Output.raw is required when capturing
  5459 already output material that will eventually be presented to the user
  5460 a second time.  For the default print mode, both Output.output and
  5461 Output.raw have no effect.
  5462 
  5463 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  5464 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  5465 cumulative results are displayed at the end of a batch session.
  5466 
  5467 * Pure/General: File.sysify_path and File.quote_sysify path have been
  5468 replaced by File.platform_path and File.shell_path (with appropriate
  5469 hooks).  This provides a clean interface for unusual systems where the
  5470 internal and external process view of file names are different.
  5471 
  5472 * Pure: more efficient orders for basic syntactic entities: added
  5473 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  5474 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  5475 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  5476 orders now -- potential INCOMPATIBILITY for code that depends on a
  5477 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  5478 Library.sort_strings on result).
  5479 
  5480 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  5481 fold_types traverse types/terms from left to right, observing natural
  5482 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  5483 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  5484 
  5485 * Pure: name spaces have been refined, with significant changes of the
  5486 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  5487 to extern(_table).  The plain name entry path is superceded by a
  5488 general 'naming' context, which also includes the 'policy' to produce
  5489 a fully qualified name and external accesses of a fully qualified
  5490 name; NameSpace.extend is superceded by context dependent
  5491 Sign.declare_name.  Several theory and proof context operations modify
  5492 the naming context.  Especially note Theory.restore_naming and
  5493 ProofContext.restore_naming to get back to a sane state; note that
  5494 Theory.add_path is no longer sufficient to recover from
  5495 Theory.absolute_path in particular.
  5496 
  5497 * Pure: new flags short_names (default false) and unique_names
  5498 (default true) for controlling output of qualified names.  If
  5499 short_names is set, names are printed unqualified.  If unique_names is
  5500 reset, the name prefix is reduced to the minimum required to achieve
  5501 the original result when interning again, even if there is an overlap
  5502 with earlier declarations.
  5503 
  5504 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  5505 now 'extend', and 'merge' gets an additional Pretty.pp argument
  5506 (useful for printing error messages).  INCOMPATIBILITY.
  5507 
  5508 * Pure: major reorganization of the theory context.  Type Sign.sg and
  5509 Theory.theory are now identified, referring to the universal
  5510 Context.theory (see Pure/context.ML).  Actual signature and theory
  5511 content is managed as theory data.  The old code and interfaces were
  5512 spread over many files and structures; the new arrangement introduces
  5513 considerable INCOMPATIBILITY to gain more clarity:
  5514 
  5515   Context -- theory management operations (name, identity, inclusion,
  5516     parents, ancestors, merge, etc.), plus generic theory data;
  5517 
  5518   Sign -- logical signature and syntax operations (declaring consts,
  5519     types, etc.), plus certify/read for common entities;
  5520 
  5521   Theory -- logical theory operations (stating axioms, definitions,
  5522     oracles), plus a copy of logical signature operations (consts,
  5523     types, etc.); also a few basic management operations (Theory.copy,
  5524     Theory.merge, etc.)
  5525 
  5526 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  5527 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  5528 for convenience -- they merely return the theory.
  5529 
  5530 * Pure: type Type.tsig is superceded by theory in most interfaces.
  5531 
  5532 * Pure: the Isar proof context type is already defined early in Pure
  5533 as Context.proof (note that ProofContext.context and Proof.context are
  5534 aliases, where the latter is the preferred name).  This enables other
  5535 Isabelle components to refer to that type even before Isar is present.
  5536 
  5537 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  5538 typeK, constK, axiomK, oracleK), but provide explicit operations for
  5539 any of these kinds.  For example, Sign.intern typeK is now
  5540 Sign.intern_type, Theory.hide_space Sign.typeK is now
  5541 Theory.hide_types.  Also note that former
  5542 Theory.hide_classes/types/consts are now
  5543 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  5544 internalize their arguments!  INCOMPATIBILITY.
  5545 
  5546 * Pure: get_thm interface (of PureThy and ProofContext) expects
  5547 datatype thmref (with constructors Name and NameSelection) instead of
  5548 plain string -- INCOMPATIBILITY;
  5549 
  5550 * Pure: cases produced by proof methods specify options, where NONE
  5551 means to remove case bindings -- INCOMPATIBILITY in
  5552 (RAW_)METHOD_CASES.
  5553 
  5554 * Pure: the following operations retrieve axioms or theorems from a
  5555 theory node or theory hierarchy, respectively:
  5556 
  5557   Theory.axioms_of: theory -> (string * term) list
  5558   Theory.all_axioms_of: theory -> (string * term) list
  5559   PureThy.thms_of: theory -> (string * thm) list
  5560   PureThy.all_thms_of: theory -> (string * thm) list
  5561 
  5562 * Pure: print_tac now outputs the goal through the trace channel.
  5563 
  5564 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  5565 Reference Toplevel.debug (default false) controls detailed printing
  5566 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  5567 controls execution profiling -- set to 1 for time and 2 for space
  5568 (both increase the runtime).
  5569 
  5570 * Isar session: The initial use of ROOT.ML is now always timed,
  5571 i.e. the log will show the actual process times, in contrast to the
  5572 elapsed wall-clock time that the outer shell wrapper produces.
  5573 
  5574 * Simplifier: improved handling of bound variables (nameless
  5575 representation, avoid allocating new strings).  Simprocs that invoke
  5576 the Simplifier recursively should use Simplifier.inherit_bounds to
  5577 avoid local name clashes.  Failure to do so produces warnings
  5578 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  5579 for further details.
  5580 
  5581 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  5582 bindings for all theorems stored within a given theory; this may help
  5583 in porting non-Isar theories to Isar ones, while keeping ML proof
  5584 scripts for the time being.
  5585 
  5586 * ML operator HTML.with_charset specifies the charset begin used for
  5587 generated HTML files.  For example:
  5588 
  5589   HTML.with_charset "utf-8" use_thy "Hebrew";
  5590   HTML.with_charset "utf-8" use_thy "Chinese";
  5591 
  5592 
  5593 *** System ***
  5594 
  5595 * Allow symlinks to all proper Isabelle executables (Isabelle,
  5596 isabelle, isatool etc.).
  5597 
  5598 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  5599 isatool doc, isatool mkdir, display_drafts etc.).
  5600 
  5601 * isatool usedir: option -f allows specification of the ML file to be
  5602 used by Isabelle; default is ROOT.ML.
  5603 
  5604 * New isatool version outputs the version identifier of the Isabelle
  5605 distribution being used.
  5606 
  5607 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  5608 (containing Boolean satisfiability problems) into Isabelle/HOL
  5609 theories.
  5610 
  5611 
  5612 
  5613 New in Isabelle2004 (April 2004)
  5614 --------------------------------
  5615 
  5616 *** General ***
  5617 
  5618 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  5619   Replaces linorder.ML.
  5620 
  5621 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  5622   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  5623   (\<a>...\<z>), are now considered normal letters, and can therefore
  5624   be used anywhere where an ASCII letter (a...zA...Z) has until
  5625   now. COMPATIBILITY: This obviously changes the parsing of some
  5626   terms, especially where a symbol has been used as a binder, say
  5627   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  5628   as an identifier.  Fix it by inserting a space around former
  5629   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  5630   existing theory and ML files.
  5631 
  5632 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  5633 
  5634 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  5635   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  5636   a normal (but invisible) letter. For multiple letter subscripts repeat
  5637   \<^isub> like this: x\<^isub>1\<^isub>2.
  5638 
  5639 * Pure: There are now sub-/superscripts that can span more than one
  5640   character. Text between \<^bsub> and \<^esub> is set in subscript in
  5641   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  5642   superscript. The new control characters are not identifier parts.
  5643 
  5644 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5645   content of "..." to the latex file instead of \isacntrl... . The "..."
  5646   may consist of any printable characters excluding the end bracket >.
  5647 
  5648 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5649   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5650   declare constants "final", which prevents their being given a definition
  5651   later.  It is useful for constants whose behaviour is fixed axiomatically
  5652   rather than definitionally, such as the meta-logic connectives.
  5653 
  5654 * Pure: 'instance' now handles general arities with general sorts
  5655   (i.e. intersections of classes),
  5656 
  5657 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5658   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5659   It can be changed to alter the colors/layout of generated pages.
  5660 
  5661 
  5662 *** Isar ***
  5663 
  5664 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5665   cut_tac, subgoal_tac and thin_tac:
  5666   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5667     locales are no longer forced to write Isar proof scripts.
  5668     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5669     emulations.
  5670   - INCOMPATIBILITY: names of variables to be instantiated may no
  5671     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5672     This is consistent with the instantiation attribute "where".
  5673 
  5674 * Attributes "where" and "of":
  5675   - Now take type variables of instantiated theorem into account when reading
  5676     the instantiation string.  This fixes a bug that caused instantiated
  5677     theorems to have too special types in some circumstances.
  5678   - "where" permits explicit instantiations of type variables.
  5679 
  5680 * Calculation commands "moreover" and "also" no longer interfere with
  5681   current facts ("this"), admitting arbitrary combinations with "then"
  5682   and derived forms.
  5683 
  5684 * Locales:
  5685   - Goal statements involving the context element "includes" no longer
  5686     generate theorems with internal delta predicates (those ending on
  5687     "_axioms") in the premise.
  5688     Resolve particular premise with <locale>.intro to obtain old form.
  5689   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5690     specification and "includes" elements in goal statement.
  5691   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5692     [intro?] and [elim?] (respectively) by default.
  5693   - Experimental command for instantiation of locales in proof contexts:
  5694         instantiate <label>[<attrs>]: <loc>
  5695     Instantiates locale <loc> and adds all its theorems to the current context
  5696     taking into account their attributes.  Label and attrs are optional
  5697     modifiers, like in theorem declarations.  If present, names of
  5698     instantiated theorems are qualified with <label>, and the attributes
  5699     <attrs> are applied after any attributes these theorems might have already.
  5700       If the locale has assumptions, a chained fact of the form
  5701     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5702     are derived.  The command does not support old-style locales declared
  5703     with "locale (open)".
  5704       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5705 
  5706 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5707   (Isar) contexts.
  5708 
  5709 
  5710 *** HOL ***
  5711 
  5712 * Proof import: new image HOL4 contains the imported library from
  5713   the HOL4 system with about 2500 theorems. It is imported by
  5714   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5715   can be used like any other Isabelle image.  See
  5716   HOL/Import/HOL/README for more information.
  5717 
  5718 * Simplifier:
  5719   - Much improved handling of linear and partial orders.
  5720     Reasoners for linear and partial orders are set up for type classes
  5721     "linorder" and "order" respectively, and are added to the default simpset
  5722     as solvers.  This means that the simplifier can build transitivity chains
  5723     to solve goals from the assumptions.
  5724   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5725     of blast or auto after simplification become unnecessary because the goal
  5726     is solved by simplification already.
  5727 
  5728 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5729     all proved in axiomatic type classes for semirings, rings and fields.
  5730 
  5731 * Numerics:
  5732   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5733     now formalized using the Ring_and_Field theory mentioned above.
  5734   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5735     than before, because now they are set up once in a generic manner.
  5736   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5737     Look for the general versions in Ring_and_Field (and Power if they concern
  5738     exponentiation).
  5739 
  5740 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5741 
  5742 * Records:
  5743   - Record types are now by default printed with their type abbreviation
  5744     instead of the list of all field types. This can be configured via
  5745     the reference "print_record_type_abbr".
  5746   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5747     (not enabled by default).
  5748   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5749     EX x. x = sel r to True (not enabled by default).
  5750   - Tactic "record_split_simp_tac" to split and simplify records added.
  5751 
  5752 * 'specification' command added, allowing for definition by
  5753   specification.  There is also an 'ax_specification' command that
  5754   introduces the new constants axiomatically.
  5755 
  5756 * arith(_tac) is now able to generate counterexamples for reals as well.
  5757 
  5758 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5759 
  5760 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5761   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5762 
  5763 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5764   matrix theory to linear programming.
  5765 
  5766 * Unions and Intersections:
  5767   The latex output syntax of UN and INT has been changed
  5768   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5769   i.e. the index formulae has become a subscript.
  5770   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5771 
  5772 * Unions and Intersections over Intervals:
  5773   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5774   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5775   like in normal math, and corresponding versions for < and for intersection.
  5776 
  5777 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5778   lexicographic dictonary ordering has been added as "lexord".
  5779 
  5780 * ML: the legacy theory structures Int and List have been removed. They had
  5781   conflicted with ML Basis Library structures having the same names.
  5782 
  5783 * 'refute' command added to search for (finite) countermodels.  Only works
  5784   for a fragment of HOL.  The installation of an external SAT solver is
  5785   highly recommended.  See "HOL/Refute.thy" for details.
  5786 
  5787 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5788   formulae under an assignment of free variables to random values.
  5789   In contrast to 'refute', it can deal with inductive datatypes,
  5790   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5791   for examples.
  5792 
  5793 
  5794 *** HOLCF ***
  5795 
  5796 * Streams now come with concatenation and are part of the HOLCF image
  5797 
  5798 
  5799 
  5800 New in Isabelle2003 (May 2003)
  5801 ------------------------------
  5802 
  5803 *** General ***
  5804 
  5805 * Provers/simplifier:
  5806 
  5807   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5808     Assumptions are now subject to complete mutual simplification,
  5809     not just from left to right. The simplifier now preserves
  5810     the order of assumptions.
  5811 
  5812     Potential INCOMPATIBILITY:
  5813 
  5814     -- simp sometimes diverges where the old version did
  5815        not, e.g. invoking simp on the goal
  5816 
  5817         [| P (f x); y = x; f x = f y |] ==> Q
  5818 
  5819        now gives rise to the infinite reduction sequence
  5820 
  5821         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5822 
  5823        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5824        kind of problem.
  5825 
  5826     -- Tactics combining classical reasoner and simplification (such as auto)
  5827        are also affected by this change, because many of them rely on
  5828        simp. They may sometimes diverge as well or yield a different numbers
  5829        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5830        in case of problems. Sometimes subsequent calls to the classical
  5831        reasoner will fail because a preceeding call to the simplifier too
  5832        eagerly simplified the goal, e.g. deleted redundant premises.
  5833 
  5834   - The simplifier trace now shows the names of the applied rewrite rules
  5835 
  5836   - You can limit the number of recursive invocations of the simplifier
  5837     during conditional rewriting (where the simplifie tries to solve the
  5838     conditions before applying the rewrite rule):
  5839     ML "simp_depth_limit := n"
  5840     where n is an integer. Thus you can force termination where previously
  5841     the simplifier would diverge.
  5842 
  5843   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5844 
  5845   - No longer aborts on failed congruence proof.  Instead, the
  5846     congruence is ignored.
  5847 
  5848 * Pure: New generic framework for extracting programs from constructive
  5849   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5850   as HOL/Extraction for some case studies.
  5851 
  5852 * Pure: The main goal of the proof state is no longer shown by default, only
  5853 the subgoals. This behaviour is controlled by a new flag.
  5854    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5855 (ML: Proof.show_main_goal).
  5856 
  5857 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5858 rules whose conclusion matches subgoal 1:
  5859       PG menu: Isabelle/Isar -> Show me -> matching rules
  5860 The rules are ordered by how closely they match the subgoal.
  5861 In particular, rules that solve a subgoal outright are displayed first
  5862 (or rather last, the way they are printed).
  5863 (ML: ProofGeneral.print_intros())
  5864 
  5865 * Pure: New flag trace_unify_fail causes unification to print
  5866 diagnostic information (PG: in trace buffer) when it fails. This is
  5867 useful for figuring out why single step proofs like rule, erule or
  5868 assumption failed.
  5869 
  5870 * Pure: Locale specifications now produce predicate definitions
  5871 according to the body of text (covering assumptions modulo local
  5872 definitions); predicate "loc_axioms" covers newly introduced text,
  5873 while "loc" is cumulative wrt. all included locale expressions; the
  5874 latter view is presented only on export into the global theory
  5875 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5876 on the old view without predicates;
  5877 
  5878 * Pure: predefined locales "var" and "struct" are useful for sharing
  5879 parameters (as in CASL, for example); just specify something like
  5880 ``var x + var y + struct M'' as import;
  5881 
  5882 * Pure: improved thms_containing: proper indexing of facts instead of
  5883 raw theorems; check validity of results wrt. current name space;
  5884 include local facts of proof configuration (also covers active
  5885 locales), cover fixed variables in index; may use "_" in term
  5886 specification; an optional limit for the number of printed facts may
  5887 be given (the default is 40);
  5888 
  5889 * Pure: disallow duplicate fact bindings within new-style theory files
  5890 (batch-mode only);
  5891 
  5892 * Provers: improved induct method: assumptions introduced by case
  5893 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5894 the goal statement); "foo" still refers to all facts collectively;
  5895 
  5896 * Provers: the function blast.overloaded has been removed: all constants
  5897 are regarded as potentially overloaded, which improves robustness in exchange
  5898 for slight decrease in efficiency;
  5899 
  5900 * Provers/linorder: New generic prover for transitivity reasoning over
  5901 linear orders.  Note: this prover is not efficient!
  5902 
  5903 * Isar: preview of problems to finish 'show' now produce an error
  5904 rather than just a warning (in interactive mode);
  5905 
  5906 
  5907 *** HOL ***
  5908 
  5909 * arith(_tac)
  5910 
  5911  - Produces a counter example if it cannot prove a goal.
  5912    Note that the counter example may be spurious if the goal is not a formula
  5913    of quantifier-free linear arithmetic.
  5914    In ProofGeneral the counter example appears in the trace buffer.
  5915 
  5916  - Knows about div k and mod k where k is a numeral of type nat or int.
  5917 
  5918  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  5919    linear arithmetic fails. This takes account of quantifiers and divisibility.
  5920    Presburger arithmetic can also be called explicitly via presburger(_tac).
  5921 
  5922 * simp's arithmetic capabilities have been enhanced a bit: it now
  5923 takes ~= in premises into account (by performing a case split);
  5924 
  5925 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  5926 are distributed over a sum of terms;
  5927 
  5928 * New tactic "trans_tac" and method "trans" instantiate
  5929 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  5930 "<=", "<" and "=").
  5931 
  5932 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  5933 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  5934 
  5935 * 'typedef' command has new option "open" to suppress the set
  5936 definition;
  5937 
  5938 * functions Min and Max on finite sets have been introduced (theory
  5939 Finite_Set);
  5940 
  5941 * attribute [symmetric] now works for relations as well; it turns
  5942 (x,y) : R^-1 into (y,x) : R, and vice versa;
  5943 
  5944 * induct over a !!-quantified statement (say !!x1..xn):
  5945   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  5946 
  5947 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  5948 %x. None. Warning: empty_def now refers to the previously hidden definition
  5949 of the empty set.
  5950 
  5951 * Algebra: formalization of classical algebra.  Intended as base for
  5952 any algebraic development in Isabelle.  Currently covers group theory
  5953 (up to Sylow's theorem) and ring theory (Universal Property of
  5954 Univariate Polynomials).  Contributions welcome;
  5955 
  5956 * GroupTheory: deleted, since its material has been moved to Algebra;
  5957 
  5958 * Complex: new directory of the complex numbers with numeric constants,
  5959 nonstandard complex numbers, and some complex analysis, standard and
  5960 nonstandard (Jacques Fleuriot);
  5961 
  5962 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  5963 
  5964 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  5965 Fleuriot);
  5966 
  5967 * Real/HahnBanach: updated and adapted to locales;
  5968 
  5969 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  5970 Gray and Kramer);
  5971 
  5972 * UNITY: added the Meier-Sanders theory of progress sets;
  5973 
  5974 * MicroJava: bytecode verifier and lightweight bytecode verifier
  5975 as abstract algorithms, instantiated to the JVM;
  5976 
  5977 * Bali: Java source language formalization. Type system, operational
  5978 semantics, axiomatic semantics. Supported language features:
  5979 classes, interfaces, objects,virtual methods, static methods,
  5980 static/instance fields, arrays, access modifiers, definite
  5981 assignment, exceptions.
  5982 
  5983 
  5984 *** ZF ***
  5985 
  5986 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  5987 universe, etc.);
  5988 
  5989 * Main ZF: virtually all theories converted to new-style format;
  5990 
  5991 
  5992 *** ML ***
  5993 
  5994 * Pure: Tactic.prove provides sane interface for internal proofs;
  5995 omits the infamous "standard" operation, so this is more appropriate
  5996 than prove_goalw_cterm in many situations (e.g. in simprocs);
  5997 
  5998 * Pure: improved error reporting of simprocs;
  5999 
  6000 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  6001 up simprocs;
  6002 
  6003 
  6004 *** Document preparation ***
  6005 
  6006 * uses \par instead of \\ for line breaks in theory text. This may
  6007 shift some page breaks in large documents. To get the old behaviour
  6008 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  6009 
  6010 * minimized dependencies of isabelle.sty and isabellesym.sty on
  6011 other packages
  6012 
  6013 * \<euro> now needs package babel/greek instead of marvosym (which
  6014 broke \Rightarrow)
  6015 
  6016 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  6017 textcomp package)
  6018 
  6019 
  6020 
  6021 New in Isabelle2002 (March 2002)
  6022 --------------------------------
  6023 
  6024 *** Document preparation ***
  6025 
  6026 * greatly simplified document preparation setup, including more
  6027 graceful interpretation of isatool usedir -i/-d/-D options, and more
  6028 instructive isatool mkdir; users should basically be able to get
  6029 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  6030 users may run a separate document processing stage manually like this:
  6031 "isatool usedir -D output HOL Test && isatool document Test/output";
  6032 
  6033 * theory dependency graph may now be incorporated into documents;
  6034 isatool usedir -g true will produce session_graph.eps/.pdf for use
  6035 with \includegraphics of LaTeX;
  6036 
  6037 * proper spacing of consecutive markup elements, especially text
  6038 blocks after section headings;
  6039 
  6040 * support bold style (for single symbols only), input syntax is like
  6041 this: "\<^bold>\<alpha>" or "\<^bold>A";
  6042 
  6043 * \<bullet> is now output as bold \cdot by default, which looks much
  6044 better in printed text;
  6045 
  6046 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  6047 note that these symbols are currently unavailable in Proof General /
  6048 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  6049 
  6050 * isatool latex no longer depends on changed TEXINPUTS, instead
  6051 isatool document copies the Isabelle style files to the target
  6052 location;
  6053 
  6054 
  6055 *** Isar ***
  6056 
  6057 * Pure/Provers: improved proof by cases and induction;
  6058   - 'case' command admits impromptu naming of parameters (such as
  6059     "case (Suc n)");
  6060   - 'induct' method divinates rule instantiation from the inductive
  6061     claim; no longer requires excessive ?P bindings for proper
  6062     instantiation of cases;
  6063   - 'induct' method properly enumerates all possibilities of set/type
  6064     rules; as a consequence facts may be also passed through *type*
  6065     rules without further ado;
  6066   - 'induct' method now derives symbolic cases from the *rulified*
  6067     rule (before it used to rulify cases stemming from the internal
  6068     atomized version); this means that the context of a non-atomic
  6069     statement becomes is included in the hypothesis, avoiding the
  6070     slightly cumbersome show "PROP ?case" form;
  6071   - 'induct' may now use elim-style induction rules without chaining
  6072     facts, using ``missing'' premises from the goal state; this allows
  6073     rules stemming from inductive sets to be applied in unstructured
  6074     scripts, while still benefitting from proper handling of non-atomic
  6075     statements; NB: major inductive premises need to be put first, all
  6076     the rest of the goal is passed through the induction;
  6077   - 'induct' proper support for mutual induction involving non-atomic
  6078     rule statements (uses the new concept of simultaneous goals, see
  6079     below);
  6080   - append all possible rule selections, but only use the first
  6081     success (no backtracking);
  6082   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  6083   - undeclared rule case names default to numbers 1, 2, 3, ...;
  6084   - added 'print_induct_rules' (covered by help item in recent Proof
  6085     General versions);
  6086   - moved induct/cases attributes to Pure, methods to Provers;
  6087   - generic method setup instantiated for FOL and HOL;
  6088 
  6089 * Pure: support multiple simultaneous goal statements, for example
  6090 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  6091 meta-level mechanism, this acts as if several individual goals had
  6092 been stated separately; in particular common proof methods need to be
  6093 repeated in order to cover all claims; note that a single elimination
  6094 step is *not* sufficient to establish the two conjunctions, so this
  6095 fails:
  6096 
  6097   assume "A & B" then have A and B ..   (*".." fails*)
  6098 
  6099 better use "obtain" in situations as above; alternative refer to
  6100 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  6101 
  6102 * Pure: proper integration with ``locales''; unlike the original
  6103 version by Florian Kammller, Isar locales package high-level proof
  6104 contexts rather than raw logical ones (e.g. we admit to include
  6105 attributes everywhere); operations on locales include merge and
  6106 rename; support for implicit arguments (``structures''); simultaneous
  6107 type-inference over imports and text; see also HOL/ex/Locales.thy for
  6108 some examples;
  6109 
  6110 * Pure: the following commands have been ``localized'', supporting a
  6111 target locale specification "(in name)": 'lemma', 'theorem',
  6112 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  6113 stored both within the locale and at the theory level (exported and
  6114 qualified by the locale name);
  6115 
  6116 * Pure: theory goals may now be specified in ``long'' form, with
  6117 ad-hoc contexts consisting of arbitrary locale elements. for example
  6118 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  6119 definitions may be given, too); the result is a meta-level rule with
  6120 the context elements being discharged in the obvious way;
  6121 
  6122 * Pure: new proof command 'using' allows to augment currently used
  6123 facts after a goal statement ('using' is syntactically analogous to
  6124 'apply', but acts on the goal's facts only); this allows chained facts
  6125 to be separated into parts given before and after a claim, as in
  6126 ``from a and b have C using d and e <proof>'';
  6127 
  6128 * Pure: renamed "antecedent" case to "rule_context";
  6129 
  6130 * Pure: new 'judgment' command records explicit information about the
  6131 object-logic embedding (used by several tools internally); no longer
  6132 use hard-wired "Trueprop";
  6133 
  6134 * Pure: added 'corollary' command;
  6135 
  6136 * Pure: fixed 'token_translation' command;
  6137 
  6138 * Pure: removed obsolete 'exported' attribute;
  6139 
  6140 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  6141 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  6142 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  6143 
  6144 * Pure: method 'atomize' presents local goal premises as object-level
  6145 statements (atomic meta-level propositions); setup controlled via
  6146 rewrite rules declarations of 'atomize' attribute; example
  6147 application: 'induct' method with proper rule statements in improper
  6148 proof *scripts*;
  6149 
  6150 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  6151 now consider the syntactic context of assumptions, giving a better
  6152 chance to get type-inference of the arguments right (this is
  6153 especially important for locales);
  6154 
  6155 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  6156 mode;
  6157 
  6158 * Pure/obtain: the formal conclusion "thesis", being marked as
  6159 ``internal'', may no longer be reference directly in the text;
  6160 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  6161 situations;
  6162 
  6163 * Pure: generic 'sym' attribute which declares a rule both as pure
  6164 'elim?' and for the 'symmetric' operation;
  6165 
  6166 * Pure: marginal comments ``--'' may now occur just anywhere in the
  6167 text; the fixed correlation with particular command syntax has been
  6168 discontinued;
  6169 
  6170 * Pure: new method 'rules' is particularly well-suited for proof
  6171 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  6172 but often produces more compact proof terms with less detours;
  6173 
  6174 * Pure/Provers/classical: simplified integration with pure rule
  6175 attributes and methods; the classical "intro?/elim?/dest?"
  6176 declarations coincide with the pure ones; the "rule" method no longer
  6177 includes classically swapped intros; "intro" and "elim" methods no
  6178 longer pick rules from the context; also got rid of ML declarations
  6179 AddXIs/AddXEs/AddXDs; all of this has some potential for
  6180 INCOMPATIBILITY;
  6181 
  6182 * Provers/classical: attribute 'swapped' produces classical inversions
  6183 of introduction rules;
  6184 
  6185 * Provers/simplifier: 'simplified' attribute may refer to explicit
  6186 rules instead of full simplifier context; 'iff' attribute handles
  6187 conditional rules;
  6188 
  6189 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  6190 
  6191 * HOL: 'recdef' now fails on unfinished automated proofs, use
  6192 "(permissive)" option to recover old behavior;
  6193 
  6194 * HOL: 'inductive' no longer features separate (collective) attributes
  6195 for 'intros' (was found too confusing);
  6196 
  6197 * HOL: properly declared induction rules less_induct and
  6198 wf_induct_rule;
  6199 
  6200 
  6201 *** HOL ***
  6202 
  6203 * HOL: moved over to sane numeral syntax; the new policy is as
  6204 follows:
  6205 
  6206   - 0 and 1 are polymorphic constants, which are defined on any
  6207   numeric type (nat, int, real etc.);
  6208 
  6209   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  6210   binary representation internally;
  6211 
  6212   - type nat has special constructor Suc, and generally prefers Suc 0
  6213   over 1::nat and Suc (Suc 0) over 2::nat;
  6214 
  6215 This change may cause significant problems of INCOMPATIBILITY; here
  6216 are some hints on converting existing sources:
  6217 
  6218   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  6219   entities, so expressions involving "-" (unary or binary minus) need
  6220   to be spaced properly;
  6221 
  6222   - existing occurrences of "1" may need to be constraint "1::nat" or
  6223   even replaced by Suc 0; similar for old "2";
  6224 
  6225   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  6226 
  6227   - remove all special provisions on numerals in proofs;
  6228 
  6229 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  6230 representation (depends on bin_arith_simps in the default context);
  6231 
  6232 * HOL: symbolic syntax for x^2 (numeral 2);
  6233 
  6234 * HOL: the class of all HOL types is now called "type" rather than