NEWS
author blanchet
Mon Jun 27 14:56:29 2011 +0200 (2011-06-27)
changeset 43573 81f7dca3e542
parent 43570 ccfb3623a68a
child 43581 c3e4d280bdeb
permissions -rw-r--r--
minor Sledgehammer news
     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) has been discontinued.
    26 Note that the path element ~~ may be used to reference theories in the
    27 Isabelle home folder -- for instance, "~~/src/HOL/Library/FuncSet".
    28 INCOMPATIBILITY.
    29 
    30 * Various optional external tools are referenced more robustly and
    31 uniformly by explicit Isabelle settings as follows:
    32 
    33   ISABELLE_CSDP   (formerly CSDP_EXE)
    34   ISABELLE_GHC    (formerly EXEC_GHC or GHC_PATH)
    35   ISABELLE_OCAML  (formerly EXEC_OCAML)
    36   ISABELLE_SWIPL  (formerly EXEC_SWIPL)
    37   ISABELLE_YAP    (formerly EXEC_YAP)
    38 
    39 Note that automated detection from the file-system or search path has
    40 been discontinued.  INCOMPATIBILITY.
    41 
    42 * Name space: former unsynchronized references are now proper
    43 configuration options, with more conventional names:
    44 
    45   long_names   ~> names_long
    46   short_names  ~> names_short
    47   unique_names ~> names_unique
    48 
    49 Minor INCOMPATIBILITY, need to declare options in context like this:
    50 
    51   declare [[names_unique = false]]
    52 
    53 * Literal facts `prop` may contain dummy patterns, e.g. `_ = _`.  Note
    54 that the result needs to be unique, which means fact specifications
    55 may have to be refined after enriching a proof context.
    56 
    57 * Isabelle/Isar reference manual provides more formal references in
    58 syntax diagrams.
    59 
    60 
    61 *** HOL ***
    62 
    63 * Finite_Set.thy: more coherent development of fold_set locales:
    64 
    65     locale fun_left_comm ~> locale comp_fun_commute
    66     locale fun_left_comm_idem ~> locale comp_fun_idem
    67     
    68 Both use point-free characterisation; interpretation proofs may need adjustment.
    69 INCOMPATIBILITY.
    70 
    71 * Code generation:
    72   - theory Library/Code_Char_ord provides native ordering of characters
    73     in the target language.
    74     
    75 * Declare ext [intro] by default.  Rare INCOMPATIBILITY.
    76 
    77 * Nitpick:
    78   - Added "need" and "total_consts" options.
    79   - Reintroduced "show_skolems" option by popular demand.
    80   - Renamed attribute: nitpick_def ~> nitpick_unfold.
    81     INCOMPATIBILITY.
    82 
    83 * Sledgehammer:
    84   - sledgehammer available_provers ~> sledgehammer supported_provers
    85     INCOMPATIBILITY.
    86   - Added support for SNARK and ToFoF-E on SystemOnTPTP and for simply typed
    87     TPTP problems (TFF).
    88   - Added "type_sys", "sound", "max_mono_iters", and "max_new_mono_instances"
    89     options.
    90   - Removed "full_types" option and corresponding Proof General menu item.
    91     INCOMPATIBILITY.
    92 
    93 * Metis:
    94   - Removed "metisF" -- use "metis" instead. INCOMPATIBILITY.
    95   - Obsoleted "metisFT" -- use "metis (full_types)" instead. INCOMPATIBILITY.
    96 
    97 * "try":
    98   - Renamed "try_methods" and added "simp:", "intro:", "dest:", and "elim:"
    99     options. INCOMPATIBILITY.
   100   - Introduced "try" that not only runs "try_methods" but also "solve_direct",
   101     "sledgehammer", "quickcheck", and "nitpick".
   102 
   103 * Quickcheck:
   104   - Added "eval" option to evaluate terms for the found counterexample
   105     (currently only supported by the default (exhaustive) tester)
   106   - Added post-processing of terms to obtain readable counterexamples
   107     (currently only supported by the default (exhaustive) tester)
   108   - New counterexample generator quickcheck[narrowing] enables
   109     narrowing-based testing.
   110     It requires that the Glasgow Haskell compiler is installed and
   111     its location is known to Isabelle with the environment variable
   112     ISABELLE_GHC.
   113 
   114 * Function package: discontinued option "tailrec".
   115 INCOMPATIBILITY. Use partial_function instead.
   116 
   117 * HOL-Probability:
   118   - Caratheodory's extension lemma is now proved for ring_of_sets.
   119   - Infinite products of probability measures are now available.
   120   - Use extended reals instead of positive extended reals.
   121     INCOMPATIBILITY.
   122 
   123 
   124 *** Document preparation ***
   125 
   126 * Antiquotation @{rail} layouts railroad syntax diagrams, see also
   127 isar-ref manual.
   128 
   129 * Localized \isabellestyle switch can be used within blocks or groups
   130 like this:
   131 
   132   \isabellestyle{it}  %preferred default
   133   {\isabellestylett @{text "typewriter stuff"}}
   134 
   135 * New term style "isub" as ad-hoc conversion of variables x1, y23 into
   136 subscripted form x\<^isub>1, y\<^isub>2\<^isub>3.
   137 
   138 * Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
   139 (e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).
   140 
   141 
   142 *** ML ***
   143 
   144 * Isabelle_Process.is_active allows tools to check if the official
   145 process wrapper is running (Isabelle/Scala/jEdit) or the old TTY loop
   146 (better known as Proof General).
   147 
   148 * Structure Proof_Context follows standard naming scheme.  Old
   149 ProofContext is still available for some time as legacy alias.
   150 
   151 * Structure Timing provides various operations for timing; supersedes
   152 former start_timing/end_timing etc.
   153 
   154 * Path.print is the official way to show file-system paths to users
   155 (including quotes etc.).
   156 
   157 * Inner syntax: identifiers in parse trees of generic categories
   158 "logic", "aprop", "idt" etc. carry position information (disguised as
   159 type constraints).  Occasional INCOMPATIBILITY with non-compliant
   160 translations that choke on unexpected type constraints.  Positions can
   161 be stripped in ML translations via Syntax.strip_positions /
   162 Syntax.strip_positions_ast, or via the syntax constant
   163 "_strip_positions" within parse trees.  As last resort, positions can
   164 be disabled via the configuration option Syntax.positions, which is
   165 called "syntax_positions" in Isar attribute syntax.
   166 
   167 * Discontinued special status of various ML structures that contribute
   168 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
   169 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
   170 refer directly to Ast.Constant, Lexicon.is_identifier,
   171 Syntax_Trans.mk_binder_tr etc.
   172 
   173 * Typed print translation: discontinued show_sorts argument, which is
   174 already available via context of "advanced" translation.
   175 
   176 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
   177 goal states; body tactic needs to address all subgoals uniformly.
   178 
   179 * Slightly more special eq_list/eq_set, with shortcut involving
   180 pointer equality (assumes that eq relation is reflexive).
   181 
   182 * Classical tactics use proper Proof.context instead of historic types
   183 claset/clasimpset.  Old-style declarations like addIs, addEs, addDs
   184 operate directly on Proof.context.  Raw type claset retains its use as
   185 snapshot of the classical context, which can be recovered via
   186 (put_claset HOL_cs) etc.  Type clasimpset has been discontinued.
   187 INCOMPATIBILITY, classical tactics and derived proof methods require
   188 proper Proof.context.
   189 
   190 
   191 
   192 New in Isabelle2011 (January 2011)
   193 ----------------------------------
   194 
   195 *** General ***
   196 
   197 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
   198 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
   199 useful tooltips and hyperlinks produced from its static analysis.  The
   200 bundled component provides an executable Isabelle tool that can be run
   201 like this:
   202 
   203   Isabelle2011/bin/isabelle jedit
   204 
   205 * Significantly improved Isabelle/Isar implementation manual.
   206 
   207 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
   208 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
   209 while the default heap location within that directory lacks that extra
   210 suffix.  This isolates multiple Isabelle installations from each
   211 other, avoiding problems with old settings in new versions.
   212 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
   213 
   214 * Source files are always encoded as UTF-8, instead of old-fashioned
   215 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
   216 the following package declarations:
   217 
   218   \usepackage[utf8]{inputenc}
   219   \usepackage{textcomp}
   220 
   221 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
   222 a Unicode character is treated as a single symbol, not a sequence of
   223 non-ASCII bytes as before.  Since Isabelle/ML string literals may
   224 contain symbols without further backslash escapes, Unicode can now be
   225 used here as well.  Recall that Symbol.explode in ML provides a
   226 consistent view on symbols, while raw explode (or String.explode)
   227 merely give a byte-oriented representation.
   228 
   229 * Theory loader: source files are primarily located via the master
   230 directory of each theory node (where the .thy file itself resides).
   231 The global load path is still partially available as legacy feature.
   232 Minor INCOMPATIBILITY due to subtle change in file lookup: use
   233 explicit paths, relatively to the theory.
   234 
   235 * Special treatment of ML file names has been discontinued.
   236 Historically, optional extensions .ML or .sml were added on demand --
   237 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
   238 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
   239 
   240 * Various options that affect pretty printing etc. are now properly
   241 handled within the context via configuration options, instead of
   242 unsynchronized references or print modes.  There are both ML Config.T
   243 entities and Isar declaration attributes to access these.
   244 
   245   ML (Config.T)                 Isar (attribute)
   246 
   247   eta_contract                  eta_contract
   248   show_brackets                 show_brackets
   249   show_sorts                    show_sorts
   250   show_types                    show_types
   251   show_question_marks           show_question_marks
   252   show_consts                   show_consts
   253   show_abbrevs                  show_abbrevs
   254 
   255   Syntax.ast_trace              syntax_ast_trace
   256   Syntax.ast_stat               syntax_ast_stat
   257   Syntax.ambiguity_level        syntax_ambiguity_level
   258 
   259   Goal_Display.goals_limit      goals_limit
   260   Goal_Display.show_main_goal   show_main_goal
   261 
   262   Method.rule_trace             rule_trace
   263 
   264   Thy_Output.display            thy_output_display
   265   Thy_Output.quotes             thy_output_quotes
   266   Thy_Output.indent             thy_output_indent
   267   Thy_Output.source             thy_output_source
   268   Thy_Output.break              thy_output_break
   269 
   270 Note that corresponding "..._default" references in ML may only be
   271 changed globally at the ROOT session setup, but *not* within a theory.
   272 The option "show_abbrevs" supersedes the former print mode
   273 "no_abbrevs" with inverted meaning.
   274 
   275 * More systematic naming of some configuration options.
   276 INCOMPATIBILITY.
   277 
   278   trace_simp  ~>  simp_trace
   279   debug_simp  ~>  simp_debug
   280 
   281 * Support for real valued configuration options, using simplistic
   282 floating-point notation that coincides with the inner syntax for
   283 float_token.
   284 
   285 * Support for real valued preferences (with approximative PGIP type):
   286 front-ends need to accept "pgint" values in float notation.
   287 INCOMPATIBILITY.
   288 
   289 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
   290 DejaVu Sans.
   291 
   292 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   293 
   294 
   295 *** Pure ***
   296 
   297 * Command 'type_synonym' (with single argument) replaces somewhat
   298 outdated 'types', which is still available as legacy feature for some
   299 time.
   300 
   301 * Command 'nonterminal' (with 'and' separated list of arguments)
   302 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
   303 
   304 * Command 'notepad' replaces former 'example_proof' for
   305 experimentation in Isar without any result.  INCOMPATIBILITY.
   306 
   307 * Locale interpretation commands 'interpret' and 'sublocale' accept
   308 lists of equations to map definitions in a locale to appropriate
   309 entities in the context of the interpretation.  The 'interpretation'
   310 command already provided this functionality.
   311 
   312 * Diagnostic command 'print_dependencies' prints the locale instances
   313 that would be activated if the specified expression was interpreted in
   314 the current context.  Variant "print_dependencies!" assumes a context
   315 without interpretations.
   316 
   317 * Diagnostic command 'print_interps' prints interpretations in proofs
   318 in addition to interpretations in theories.
   319 
   320 * Discontinued obsolete 'global' and 'local' commands to manipulate
   321 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
   322 Sign.root_path and Sign.local_path may be applied directly where this
   323 feature is still required for historical reasons.
   324 
   325 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
   326 'definition' instead.
   327 
   328 * The "prems" fact, which refers to the accidental collection of
   329 foundational premises in the context, is now explicitly marked as
   330 legacy feature and will be discontinued soon.  Consider using "assms"
   331 of the head statement or reference facts by explicit names.
   332 
   333 * Document antiquotations @{class} and @{type} print classes and type
   334 constructors.
   335 
   336 * Document antiquotation @{file} checks file/directory entries within
   337 the local file system.
   338 
   339 
   340 *** HOL ***
   341 
   342 * Coercive subtyping: functions can be declared as coercions and type
   343 inference will add them as necessary upon input of a term.  Theory
   344 Complex_Main declares real :: nat => real and real :: int => real as
   345 coercions. A coercion function f is declared like this:
   346 
   347   declare [[coercion f]]
   348 
   349 To lift coercions through type constructors (e.g. from nat => real to
   350 nat list => real list), map functions can be declared, e.g.
   351 
   352   declare [[coercion_map map]]
   353 
   354 Currently coercion inference is activated only in theories including
   355 real numbers, i.e. descendants of Complex_Main.  This is controlled by
   356 the configuration option "coercion_enabled", e.g. it can be enabled in
   357 other theories like this:
   358 
   359   declare [[coercion_enabled]]
   360 
   361 * Command 'partial_function' provides basic support for recursive
   362 function definitions over complete partial orders.  Concrete instances
   363 are provided for i) the option type, ii) tail recursion on arbitrary
   364 types, and iii) the heap monad of Imperative_HOL.  See
   365 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
   366 for examples.
   367 
   368 * Function package: f.psimps rules are no longer implicitly declared
   369 as [simp].  INCOMPATIBILITY.
   370 
   371 * Datatype package: theorems generated for executable equality (class
   372 "eq") carry proper names and are treated as default code equations.
   373 
   374 * Inductive package: now offers command 'inductive_simps' to
   375 automatically derive instantiated and simplified equations for
   376 inductive predicates, similar to 'inductive_cases'.
   377 
   378 * Command 'enriched_type' allows to register properties of the
   379 functorial structure of types.
   380 
   381 * Improved infrastructure for term evaluation using code generator
   382 techniques, in particular static evaluation conversions.
   383 
   384 * Code generator: Scala (2.8 or higher) has been added to the target
   385 languages.
   386 
   387 * Code generator: globbing constant expressions "*" and "Theory.*"
   388 have been replaced by the more idiomatic "_" and "Theory._".
   389 INCOMPATIBILITY.
   390 
   391 * Code generator: export_code without explicit file declaration prints
   392 to standard output.  INCOMPATIBILITY.
   393 
   394 * Code generator: do not print function definitions for case
   395 combinators any longer.
   396 
   397 * Code generator: simplification with rules determined with
   398 src/Tools/Code/code_simp.ML and method "code_simp".
   399 
   400 * Code generator for records: more idiomatic representation of record
   401 types.  Warning: records are not covered by ancient SML code
   402 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
   403 rep_datatype declaration helps to succeed then:
   404 
   405   record 'a foo = ...
   406   ...
   407   rep_datatype foo_ext ...
   408 
   409 * Records: logical foundation type for records does not carry a
   410 '_type' suffix any longer (obsolete due to authentic syntax).
   411 INCOMPATIBILITY.
   412 
   413 * Quickcheck now by default uses exhaustive testing instead of random
   414 testing.  Random testing can be invoked by "quickcheck [random]",
   415 exhaustive testing by "quickcheck [exhaustive]".
   416 
   417 * Quickcheck instantiates polymorphic types with small finite
   418 datatypes by default. This enables a simple execution mechanism to
   419 handle quantifiers and function equality over the finite datatypes.
   420 
   421 * Quickcheck random generator has been renamed from "code" to
   422 "random".  INCOMPATIBILITY.
   423 
   424 * Quickcheck now has a configurable time limit which is set to 30
   425 seconds by default. This can be changed by adding [timeout = n] to the
   426 quickcheck command. The time limit for Auto Quickcheck is still set
   427 independently.
   428 
   429 * Quickcheck in locales considers interpretations of that locale for
   430 counter example search.
   431 
   432 * Sledgehammer:
   433   - Added "smt" and "remote_smt" provers based on the "smt" proof
   434     method. See the Sledgehammer manual for details ("isabelle doc
   435     sledgehammer").
   436   - Renamed commands:
   437     sledgehammer atp_info ~> sledgehammer running_provers
   438     sledgehammer atp_kill ~> sledgehammer kill_provers
   439     sledgehammer available_atps ~> sledgehammer available_provers
   440     INCOMPATIBILITY.
   441   - Renamed options:
   442     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
   443     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
   444     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
   445     (and "ms" and "min" are no longer supported)
   446     INCOMPATIBILITY.
   447 
   448 * Nitpick:
   449   - Renamed options:
   450     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
   451     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
   452     INCOMPATIBILITY.
   453   - Added support for partial quotient types.
   454   - Added local versions of the "Nitpick.register_xxx" functions.
   455   - Added "whack" option.
   456   - Allow registration of quotient types as codatatypes.
   457   - Improved "merge_type_vars" option to merge more types.
   458   - Removed unsound "fast_descrs" option.
   459   - Added custom symmetry breaking for datatypes, making it possible to reach
   460     higher cardinalities.
   461   - Prevent the expansion of too large definitions.
   462 
   463 * Proof methods "metis" and "meson" now have configuration options
   464 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
   465 to diagnose these tools. E.g.
   466 
   467     using [[metis_trace = true]]
   468 
   469 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
   470 manually as command 'solve_direct'.
   471 
   472 * The default SMT solver Z3 must be enabled explicitly (due to
   473 licensing issues) by setting the environment variable
   474 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
   475 commercial applications, the SMT solver CVC3 is provided as fall-back;
   476 changing the SMT solver is done via the configuration option
   477 "smt_solver".
   478 
   479 * Remote SMT solvers need to be referred to by the "remote_" prefix,
   480 i.e. "remote_cvc3" and "remote_z3".
   481 
   482 * Added basic SMT support for datatypes, records, and typedefs using
   483 the oracle mode (no proofs).  Direct support of pairs has been dropped
   484 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
   485 support for a similar behavior).  Minor INCOMPATIBILITY.
   486 
   487 * Changed SMT configuration options:
   488   - Renamed:
   489     z3_proofs ~> smt_oracle (with inverted meaning)
   490     z3_trace_assms ~> smt_trace_used_facts
   491     INCOMPATIBILITY.
   492   - Added:
   493     smt_verbose
   494     smt_random_seed
   495     smt_datatypes
   496     smt_infer_triggers
   497     smt_monomorph_limit
   498     cvc3_options
   499     remote_cvc3_options
   500     remote_z3_options
   501     yices_options
   502 
   503 * Boogie output files (.b2i files) need to be declared in the theory
   504 header.
   505 
   506 * Simplification procedure "list_to_set_comprehension" rewrites list
   507 comprehensions applied to List.set to set comprehensions.  Occasional
   508 INCOMPATIBILITY, may be deactivated like this:
   509 
   510   declare [[simproc del: list_to_set_comprehension]]
   511 
   512 * Removed old version of primrec package.  INCOMPATIBILITY.
   513 
   514 * Removed simplifier congruence rule of "prod_case", as has for long
   515 been the case with "split".  INCOMPATIBILITY.
   516 
   517 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
   518 
   519 * Removed [split_format ... and ... and ...] version of
   520 [split_format].  Potential INCOMPATIBILITY.
   521 
   522 * Predicate "sorted" now defined inductively, with nice induction
   523 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
   524 
   525 * Constant "contents" renamed to "the_elem", to free the generic name
   526 contents for other uses.  INCOMPATIBILITY.
   527 
   528 * Renamed class eq and constant eq (for code generation) to class
   529 equal and constant equal, plus renaming of related facts and various
   530 tuning.  INCOMPATIBILITY.
   531 
   532 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
   533 
   534 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
   535 INCOMPATIBILITY.
   536 
   537 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
   538 avoid confusion with finite sets.  INCOMPATIBILITY.
   539 
   540 * Abandoned locales equiv, congruent and congruent2 for equivalence
   541 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
   542 for congruent(2)).
   543 
   544 * Some previously unqualified names have been qualified:
   545 
   546   types
   547     bool ~> HOL.bool
   548     nat ~> Nat.nat
   549 
   550   constants
   551     Trueprop ~> HOL.Trueprop
   552     True ~> HOL.True
   553     False ~> HOL.False
   554     op & ~> HOL.conj
   555     op | ~> HOL.disj
   556     op --> ~> HOL.implies
   557     op = ~> HOL.eq
   558     Not ~> HOL.Not
   559     The ~> HOL.The
   560     All ~> HOL.All
   561     Ex ~> HOL.Ex
   562     Ex1 ~> HOL.Ex1
   563     Let ~> HOL.Let
   564     If ~> HOL.If
   565     Ball ~> Set.Ball
   566     Bex ~> Set.Bex
   567     Suc ~> Nat.Suc
   568     Pair ~> Product_Type.Pair
   569     fst ~> Product_Type.fst
   570     snd ~> Product_Type.snd
   571     curry ~> Product_Type.curry
   572     op : ~> Set.member
   573     Collect ~> Set.Collect
   574 
   575 INCOMPATIBILITY.
   576 
   577 * More canonical naming convention for some fundamental definitions:
   578 
   579     bot_bool_eq ~> bot_bool_def
   580     top_bool_eq ~> top_bool_def
   581     inf_bool_eq ~> inf_bool_def
   582     sup_bool_eq ~> sup_bool_def
   583     bot_fun_eq  ~> bot_fun_def
   584     top_fun_eq  ~> top_fun_def
   585     inf_fun_eq  ~> inf_fun_def
   586     sup_fun_eq  ~> sup_fun_def
   587 
   588 INCOMPATIBILITY.
   589 
   590 * More stylized fact names:
   591 
   592   expand_fun_eq ~> fun_eq_iff
   593   expand_set_eq ~> set_eq_iff
   594   set_ext       ~> set_eqI
   595   nat_number    ~> eval_nat_numeral
   596 
   597 INCOMPATIBILITY.
   598 
   599 * Refactoring of code-generation specific operations in theory List:
   600 
   601   constants
   602     null ~> List.null
   603 
   604   facts
   605     mem_iff ~> member_def
   606     null_empty ~> null_def
   607 
   608 INCOMPATIBILITY.  Note that these were not supposed to be used
   609 regularly unless for striking reasons; their main purpose was code
   610 generation.
   611 
   612 Various operations from the Haskell prelude are used for generating
   613 Haskell code.
   614 
   615 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
   616 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
   617 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
   618 
   619 * Abolished some non-alphabetic type names: "prod" and "sum" replace
   620 "*" and "+" respectively.  INCOMPATIBILITY.
   621 
   622 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
   623 "Sum_Type.Plus" instead.
   624 
   625 * Constant "split" has been merged with constant "prod_case"; names of
   626 ML functions, facts etc. involving split have been retained so far,
   627 though.  INCOMPATIBILITY.
   628 
   629 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
   630 instead.  INCOMPATIBILITY.
   631 
   632 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
   633 INCOMPATIBILITY.
   634 
   635 * Former theory Library/Enum is now part of the HOL-Main image.
   636 INCOMPATIBILITY: all constants of the Enum theory now have to be
   637 referred to by its qualified name.
   638 
   639   enum    ~>  Enum.enum
   640   nlists  ~>  Enum.nlists
   641   product ~>  Enum.product
   642 
   643 * Theory Library/Monad_Syntax provides do-syntax for monad types.
   644 Syntax in Library/State_Monad has been changed to avoid ambiguities.
   645 INCOMPATIBILITY.
   646 
   647 * Theory Library/SetsAndFunctions has been split into
   648 Library/Function_Algebras and Library/Set_Algebras; canonical names
   649 for instance definitions for functions; various improvements.
   650 INCOMPATIBILITY.
   651 
   652 * Theory Library/Multiset provides stable quicksort implementation of
   653 sort_key.
   654 
   655 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
   656 INCOMPATIBILITY.
   657 
   658 * Session Multivariate_Analysis: introduced a type class for euclidean
   659 space.  Most theorems are now stated in terms of euclidean spaces
   660 instead of finite cartesian products.
   661 
   662   types
   663     real ^ 'n ~>  'a::real_vector
   664               ~>  'a::euclidean_space
   665               ~>  'a::ordered_euclidean_space
   666         (depends on your needs)
   667 
   668   constants
   669      _ $ _        ~> _ $$ _
   670      \<chi> x. _  ~> \<chi>\<chi> x. _
   671      CARD('n)     ~> DIM('a)
   672 
   673 Also note that the indices are now natural numbers and not from some
   674 finite type. Finite cartesian products of euclidean spaces, products
   675 of euclidean spaces the real and complex numbers are instantiated to
   676 be euclidean_spaces.  INCOMPATIBILITY.
   677 
   678 * Session Probability: introduced pextreal as positive extended real
   679 numbers.  Use pextreal as value for measures.  Introduce the
   680 Radon-Nikodym derivative, product spaces and Fubini's theorem for
   681 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
   682 the integral in Multivariate Analysis.  INCOMPATIBILITY.
   683 
   684 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   685 INCOMPATIBILITY.
   686 
   687 * Session SPARK (with image HOL-SPARK) provides commands to load and
   688 prove verification conditions generated by the SPARK Ada program
   689 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
   690 
   691 
   692 *** HOL-Algebra ***
   693 
   694 * Theorems for additive ring operations (locale abelian_monoid and
   695 descendants) are generated by interpretation from their multiplicative
   696 counterparts.  Names (in particular theorem names) have the mandatory
   697 qualifier 'add'.  Previous theorem names are redeclared for
   698 compatibility.
   699 
   700 * Structure "int_ring" is now an abbreviation (previously a
   701 definition).  This fits more natural with advanced interpretations.
   702 
   703 
   704 *** HOLCF ***
   705 
   706 * The domain package now runs in definitional mode by default: The
   707 former command 'new_domain' is now called 'domain'.  To use the domain
   708 package in its original axiomatic mode, use 'domain (unsafe)'.
   709 INCOMPATIBILITY.
   710 
   711 * The new class "domain" is now the default sort.  Class "predomain"
   712 is an unpointed version of "domain". Theories can be updated by
   713 replacing sort annotations as shown below.  INCOMPATIBILITY.
   714 
   715   'a::type ~> 'a::countable
   716   'a::cpo  ~> 'a::predomain
   717   'a::pcpo ~> 'a::domain
   718 
   719 * The old type class "rep" has been superseded by class "domain".
   720 Accordingly, users of the definitional package must remove any
   721 "default_sort rep" declarations.  INCOMPATIBILITY.
   722 
   723 * The domain package (definitional mode) now supports unpointed
   724 predomain argument types, as long as they are marked 'lazy'. (Strict
   725 arguments must be in class "domain".) For example, the following
   726 domain definition now works:
   727 
   728   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
   729 
   730 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
   731 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
   732 'a option, and 'a list.  Additionally, it configures fixrec and the
   733 domain package to work with these types.  For example:
   734 
   735   fixrec isInl :: "('a + 'b) u -> tr"
   736     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
   737 
   738   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
   739 
   740 * The "(permissive)" option of fixrec has been replaced with a
   741 per-equation "(unchecked)" option. See
   742 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
   743 
   744 * The "bifinite" class no longer fixes a constant "approx"; the class
   745 now just asserts that such a function exists.  INCOMPATIBILITY.
   746 
   747 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
   748 defines an embedding of type 'a defl into udom by default; instances
   749 of "bifinite" and "domain" classes are available in
   750 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
   751 
   752 * The syntax "REP('a)" has been replaced with "DEFL('a)".
   753 
   754 * The predicate "directed" has been removed.  INCOMPATIBILITY.
   755 
   756 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
   757 
   758 * The function "cprod_map" has been renamed to "prod_map".
   759 INCOMPATIBILITY.
   760 
   761 * The monadic bind operator on each powerdomain has new binder syntax
   762 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
   763 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
   764 
   765 * The infix syntax for binary union on each powerdomain has changed
   766 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
   767 syntax.  INCOMPATIBILITY.
   768 
   769 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
   770 still supported as an input translation.
   771 
   772 * Renamed some theorems (the original names are also still available).
   773 
   774   expand_fun_below   ~> fun_below_iff
   775   below_fun_ext      ~> fun_belowI
   776   expand_cfun_eq     ~> cfun_eq_iff
   777   ext_cfun           ~> cfun_eqI
   778   expand_cfun_below  ~> cfun_below_iff
   779   below_cfun_ext     ~> cfun_belowI
   780   cont2cont_Rep_CFun ~> cont2cont_APP
   781 
   782 * The Abs and Rep functions for various types have changed names.
   783 Related theorem names have also changed to match. INCOMPATIBILITY.
   784 
   785   Rep_CFun  ~> Rep_cfun
   786   Abs_CFun  ~> Abs_cfun
   787   Rep_Sprod ~> Rep_sprod
   788   Abs_Sprod ~> Abs_sprod
   789   Rep_Ssum  ~> Rep_ssum
   790   Abs_Ssum  ~> Abs_ssum
   791 
   792 * Lemmas with names of the form *_defined_iff or *_strict_iff have
   793 been renamed to *_bottom_iff.  INCOMPATIBILITY.
   794 
   795 * Various changes to bisimulation/coinduction with domain package:
   796 
   797   - Definitions of "bisim" constants no longer mention definedness.
   798   - With mutual recursion, "bisim" predicate is now curried.
   799   - With mutual recursion, each type gets a separate coind theorem.
   800   - Variable names in bisim_def and coinduct rules have changed.
   801 
   802 INCOMPATIBILITY.
   803 
   804 * Case combinators generated by the domain package for type "foo" are
   805 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
   806 
   807 * Several theorems have been renamed to more accurately reflect the
   808 names of constants and types involved.  INCOMPATIBILITY.
   809 
   810   thelub_const    ~> lub_const
   811   lub_const       ~> is_lub_const
   812   thelubI         ~> lub_eqI
   813   is_lub_lub      ~> is_lubD2
   814   lubI            ~> is_lub_lub
   815   unique_lub      ~> is_lub_unique
   816   is_ub_lub       ~> is_lub_rangeD1
   817   lub_bin_chain   ~> is_lub_bin_chain
   818   lub_fun         ~> is_lub_fun
   819   thelub_fun      ~> lub_fun
   820   thelub_cfun     ~> lub_cfun
   821   thelub_Pair     ~> lub_Pair
   822   lub_cprod       ~> is_lub_prod
   823   thelub_cprod    ~> lub_prod
   824   minimal_cprod   ~> minimal_prod
   825   inst_cprod_pcpo ~> inst_prod_pcpo
   826   UU_I            ~> bottomI
   827   compact_UU      ~> compact_bottom
   828   deflation_UU    ~> deflation_bottom
   829   finite_deflation_UU ~> finite_deflation_bottom
   830 
   831 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
   832 
   833   sq_ord_less_eq_trans ~> below_eq_trans
   834   sq_ord_eq_less_trans ~> eq_below_trans
   835   refl_less            ~> below_refl
   836   trans_less           ~> below_trans
   837   antisym_less         ~> below_antisym
   838   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
   839   box_less             ~> box_below
   840   rev_trans_less       ~> rev_below_trans
   841   not_less2not_eq      ~> not_below2not_eq
   842   less_UU_iff          ~> below_UU_iff
   843   flat_less_iff        ~> flat_below_iff
   844   adm_less             ~> adm_below
   845   adm_not_less         ~> adm_not_below
   846   adm_compact_not_less ~> adm_compact_not_below
   847   less_fun_def         ~> below_fun_def
   848   expand_fun_less      ~> fun_below_iff
   849   less_fun_ext         ~> fun_belowI
   850   less_discr_def       ~> below_discr_def
   851   discr_less_eq        ~> discr_below_eq
   852   less_unit_def        ~> below_unit_def
   853   less_cprod_def       ~> below_prod_def
   854   prod_lessI           ~> prod_belowI
   855   Pair_less_iff        ~> Pair_below_iff
   856   fst_less_iff         ~> fst_below_iff
   857   snd_less_iff         ~> snd_below_iff
   858   expand_cfun_less     ~> cfun_below_iff
   859   less_cfun_ext        ~> cfun_belowI
   860   injection_less       ~> injection_below
   861   less_up_def          ~> below_up_def
   862   not_Iup_less         ~> not_Iup_below
   863   Iup_less             ~> Iup_below
   864   up_less              ~> up_below
   865   Def_inject_less_eq   ~> Def_below_Def
   866   Def_less_is_eq       ~> Def_below_iff
   867   spair_less_iff       ~> spair_below_iff
   868   less_sprod           ~> below_sprod
   869   spair_less           ~> spair_below
   870   sfst_less_iff        ~> sfst_below_iff
   871   ssnd_less_iff        ~> ssnd_below_iff
   872   fix_least_less       ~> fix_least_below
   873   dist_less_one        ~> dist_below_one
   874   less_ONE             ~> below_ONE
   875   ONE_less_iff         ~> ONE_below_iff
   876   less_sinlD           ~> below_sinlD
   877   less_sinrD           ~> below_sinrD
   878 
   879 
   880 *** FOL and ZF ***
   881 
   882 * All constant names are now qualified internally and use proper
   883 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
   884 
   885 
   886 *** ML ***
   887 
   888 * Antiquotation @{assert} inlines a function bool -> unit that raises
   889 Fail if the argument is false.  Due to inlining the source position of
   890 failed assertions is included in the error output.
   891 
   892 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
   893 text is in practice always evaluated with a stable theory checkpoint.
   894 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
   895 
   896 * Antiquotation @{theory A} refers to theory A from the ancestry of
   897 the current context, not any accidental theory loader state as before.
   898 Potential INCOMPATIBILITY, subtle change in semantics.
   899 
   900 * Syntax.pretty_priority (default 0) configures the required priority
   901 of pretty-printed output and thus affects insertion of parentheses.
   902 
   903 * Syntax.default_root (default "any") configures the inner syntax
   904 category (nonterminal symbol) for parsing of terms.
   905 
   906 * Former exception Library.UnequalLengths now coincides with
   907 ListPair.UnequalLengths.
   908 
   909 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
   910 main functionality is provided by structure Simplifier.
   911 
   912 * Renamed raw "explode" function to "raw_explode" to emphasize its
   913 meaning.  Note that internally to Isabelle, Symbol.explode is used in
   914 almost all situations.
   915 
   916 * Discontinued obsolete function sys_error and exception SYS_ERROR.
   917 See implementation manual for further details on exceptions in
   918 Isabelle/ML.
   919 
   920 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
   921 meaning.
   922 
   923 * Renamed structure PureThy to Pure_Thy and moved most of its
   924 operations to structure Global_Theory, to emphasize that this is
   925 rarely-used global-only stuff.
   926 
   927 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
   928 instead (or tracing for high-volume output).
   929 
   930 * Configuration option show_question_marks only affects regular pretty
   931 printing of types and terms, not raw Term.string_of_vname.
   932 
   933 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
   934 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
   935 @{thms} for most purposes.
   936 
   937 * ML structure Unsynchronized is never opened, not even in Isar
   938 interaction mode as before.  Old Unsynchronized.set etc. have been
   939 discontinued -- use plain := instead.  This should be *rare* anyway,
   940 since modern tools always work via official context data, notably
   941 configuration options.
   942 
   943 * Parallel and asynchronous execution requires special care concerning
   944 interrupts.  Structure Exn provides some convenience functions that
   945 avoid working directly with raw Interrupt.  User code must not absorb
   946 interrupts -- intermediate handling (for cleanup etc.) needs to be
   947 followed by re-raising of the original exception.  Another common
   948 source of mistakes are "handle _" patterns, which make the meaning of
   949 the program subject to physical effects of the environment.
   950 
   951 
   952 
   953 New in Isabelle2009-2 (June 2010)
   954 ---------------------------------
   955 
   956 *** General ***
   957 
   958 * Authentic syntax for *all* logical entities (type classes, type
   959 constructors, term constants): provides simple and robust
   960 correspondence between formal entities and concrete syntax.  Within
   961 the parse tree / AST representations, "constants" are decorated by
   962 their category (class, type, const) and spelled out explicitly with
   963 their full internal name.
   964 
   965 Substantial INCOMPATIBILITY concerning low-level syntax declarations
   966 and translations (translation rules and translation functions in ML).
   967 Some hints on upgrading:
   968 
   969   - Many existing uses of 'syntax' and 'translations' can be replaced
   970     by more modern 'type_notation', 'notation' and 'abbreviation',
   971     which are independent of this issue.
   972 
   973   - 'translations' require markup within the AST; the term syntax
   974     provides the following special forms:
   975 
   976       CONST c   -- produces syntax version of constant c from context
   977       XCONST c  -- literally c, checked as constant from context
   978       c         -- literally c, if declared by 'syntax'
   979 
   980     Plain identifiers are treated as AST variables -- occasionally the
   981     system indicates accidental variables via the error "rhs contains
   982     extra variables".
   983 
   984     Type classes and type constructors are marked according to their
   985     concrete syntax.  Some old translations rules need to be written
   986     for the "type" category, using type constructor application
   987     instead of pseudo-term application of the default category
   988     "logic".
   989 
   990   - 'parse_translation' etc. in ML may use the following
   991     antiquotations:
   992 
   993       @{class_syntax c}   -- type class c within parse tree / AST
   994       @{term_syntax c}    -- type constructor c within parse tree / AST
   995       @{const_syntax c}   -- ML version of "CONST c" above
   996       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
   997 
   998   - Literal types within 'typed_print_translations', i.e. those *not*
   999     represented as pseudo-terms are represented verbatim.  Use @{class
  1000     c} or @{type_name c} here instead of the above syntax
  1001     antiquotations.
  1002 
  1003 Note that old non-authentic syntax was based on unqualified base
  1004 names, so all of the above "constant" names would coincide.  Recall
  1005 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
  1006 diagnose syntax problems.
  1007 
  1008 * Type constructors admit general mixfix syntax, not just infix.
  1009 
  1010 * Concrete syntax may be attached to local entities without a proof
  1011 body, too.  This works via regular mixfix annotations for 'fix',
  1012 'def', 'obtain' etc. or via the explicit 'write' command, which is
  1013 similar to the 'notation' command in theory specifications.
  1014 
  1015 * Discontinued unnamed infix syntax (legacy feature for many years) --
  1016 need to specify constant name and syntax separately.  Internal ML
  1017 datatype constructors have been renamed from InfixName to Infix etc.
  1018 Minor INCOMPATIBILITY.
  1019 
  1020 * Schematic theorem statements need to be explicitly markup as such,
  1021 via commands 'schematic_lemma', 'schematic_theorem',
  1022 'schematic_corollary'.  Thus the relevance of the proof is made
  1023 syntactically clear, which impacts performance in a parallel or
  1024 asynchronous interactive environment.  Minor INCOMPATIBILITY.
  1025 
  1026 * Use of cumulative prems via "!" in some proof methods has been
  1027 discontinued (old legacy feature).
  1028 
  1029 * References 'trace_simp' and 'debug_simp' have been replaced by
  1030 configuration options stored in the context. Enabling tracing (the
  1031 case of debugging is similar) in proofs works via
  1032 
  1033   using [[trace_simp = true]]
  1034 
  1035 Tracing is then active for all invocations of the simplifier in
  1036 subsequent goal refinement steps. Tracing may also still be enabled or
  1037 disabled via the ProofGeneral settings menu.
  1038 
  1039 * Separate commands 'hide_class', 'hide_type', 'hide_const',
  1040 'hide_fact' replace the former 'hide' KIND command.  Minor
  1041 INCOMPATIBILITY.
  1042 
  1043 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
  1044 more efficient than combinations with -q1 or -q2.
  1045 
  1046 
  1047 *** Pure ***
  1048 
  1049 * Proofterms record type-class reasoning explicitly, using the
  1050 "unconstrain" operation internally.  This eliminates all sort
  1051 constraints from a theorem and proof, introducing explicit
  1052 OFCLASS-premises.  On the proof term level, this operation is
  1053 automatically applied at theorem boundaries, such that closed proofs
  1054 are always free of sort constraints.  INCOMPATIBILITY for tools that
  1055 inspect proof terms.
  1056 
  1057 * Local theory specifications may depend on extra type variables that
  1058 are not present in the result type -- arguments TYPE('a) :: 'a itself
  1059 are added internally.  For example:
  1060 
  1061   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
  1062 
  1063 * Predicates of locales introduced by classes carry a mandatory
  1064 "class" prefix.  INCOMPATIBILITY.
  1065 
  1066 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
  1067 
  1068 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
  1069 'class' instead.
  1070 
  1071 * Command 'code_reflect' allows to incorporate generated ML code into
  1072 runtime environment; replaces immature code_datatype antiquotation.
  1073 INCOMPATIBILITY.
  1074 
  1075 * Code generator: simple concept for abstract datatypes obeying
  1076 invariants.
  1077 
  1078 * Code generator: details of internal data cache have no impact on the
  1079 user space functionality any longer.
  1080 
  1081 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  1082 subgoals.  This is more appropriate for interpretations with 'where'.
  1083 INCOMPATIBILITY.
  1084 
  1085 * Command 'example_proof' opens an empty proof body.  This allows to
  1086 experiment with Isar, without producing any persistent result.
  1087 
  1088 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  1089 within a local theory context, with explicit checking of the
  1090 constructors involved (in contrast to the raw 'syntax' versions).
  1091 
  1092 * Commands 'types' and 'typedecl' now work within a local theory
  1093 context -- without introducing dependencies on parameters or
  1094 assumptions, which is not possible in Isabelle/Pure.
  1095 
  1096 * Command 'defaultsort' has been renamed to 'default_sort', it works
  1097 within a local theory context.  Minor INCOMPATIBILITY.
  1098 
  1099 
  1100 *** HOL ***
  1101 
  1102 * Command 'typedef' now works within a local theory context -- without
  1103 introducing dependencies on parameters or assumptions, which is not
  1104 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  1105 contain multiple interpretations of local typedefs (with different
  1106 non-emptiness proofs), even in a global theory context.
  1107 
  1108 * New package for quotient types.  Commands 'quotient_type' and
  1109 'quotient_definition' may be used for defining types and constants by
  1110 quotient constructions.  An example is the type of integers created by
  1111 quotienting pairs of natural numbers:
  1112 
  1113   fun
  1114     intrel :: "(nat * nat) => (nat * nat) => bool"
  1115   where
  1116     "intrel (x, y) (u, v) = (x + v = u + y)"
  1117 
  1118   quotient_type int = "nat * nat" / intrel
  1119     by (auto simp add: equivp_def expand_fun_eq)
  1120 
  1121   quotient_definition
  1122     "0::int" is "(0::nat, 0::nat)"
  1123 
  1124 The method "lifting" can be used to lift of theorems from the
  1125 underlying "raw" type to the quotient type.  The example
  1126 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  1127 construction and provides a reasoning infrastructure for finite sets.
  1128 
  1129 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  1130 clash with new theory Quotient in Main HOL.
  1131 
  1132 * Moved the SMT binding into the main HOL session, eliminating
  1133 separate HOL-SMT session.
  1134 
  1135 * List membership infix mem operation is only an input abbreviation.
  1136 INCOMPATIBILITY.
  1137 
  1138 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  1139 for future developements; former Library/Word.thy is still present in
  1140 the AFP entry RSAPPS.
  1141 
  1142 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  1143 longer shadowed.  INCOMPATIBILITY.
  1144 
  1145 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  1146 INCOMPATIBILITY.
  1147 
  1148 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  1149 INCOMPATIBILITY.
  1150 
  1151 * Dropped normalizing_semiring etc; use the facts in semiring classes
  1152 instead.  INCOMPATIBILITY.
  1153 
  1154 * Dropped several real-specific versions of lemmas about floor and
  1155 ceiling; use the generic lemmas from theory "Archimedean_Field"
  1156 instead.  INCOMPATIBILITY.
  1157 
  1158   floor_number_of_eq         ~> floor_number_of
  1159   le_floor_eq_number_of      ~> number_of_le_floor
  1160   le_floor_eq_zero           ~> zero_le_floor
  1161   le_floor_eq_one            ~> one_le_floor
  1162   floor_less_eq_number_of    ~> floor_less_number_of
  1163   floor_less_eq_zero         ~> floor_less_zero
  1164   floor_less_eq_one          ~> floor_less_one
  1165   less_floor_eq_number_of    ~> number_of_less_floor
  1166   less_floor_eq_zero         ~> zero_less_floor
  1167   less_floor_eq_one          ~> one_less_floor
  1168   floor_le_eq_number_of      ~> floor_le_number_of
  1169   floor_le_eq_zero           ~> floor_le_zero
  1170   floor_le_eq_one            ~> floor_le_one
  1171   floor_subtract_number_of   ~> floor_diff_number_of
  1172   floor_subtract_one         ~> floor_diff_one
  1173   ceiling_number_of_eq       ~> ceiling_number_of
  1174   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  1175   ceiling_le_zero_eq         ~> ceiling_le_zero
  1176   ceiling_le_eq_one          ~> ceiling_le_one
  1177   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  1178   less_ceiling_eq_zero       ~> zero_less_ceiling
  1179   less_ceiling_eq_one        ~> one_less_ceiling
  1180   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  1181   ceiling_less_eq_zero       ~> ceiling_less_zero
  1182   ceiling_less_eq_one        ~> ceiling_less_one
  1183   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  1184   le_ceiling_eq_zero         ~> zero_le_ceiling
  1185   le_ceiling_eq_one          ~> one_le_ceiling
  1186   ceiling_subtract_number_of ~> ceiling_diff_number_of
  1187   ceiling_subtract_one       ~> ceiling_diff_one
  1188 
  1189 * Theory "Finite_Set": various folding_XXX locales facilitate the
  1190 application of the various fold combinators on finite sets.
  1191 
  1192 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  1193 provides abstract red-black tree type which is backed by "RBT_Impl" as
  1194 implementation.  INCOMPATIBILTY.
  1195 
  1196 * Theory Library/Coinductive_List has been removed -- superseded by
  1197 AFP/thys/Coinductive.
  1198 
  1199 * Theory PReal, including the type "preal" and related operations, has
  1200 been removed.  INCOMPATIBILITY.
  1201 
  1202 * Real: new development using Cauchy Sequences.
  1203 
  1204 * Split off theory "Big_Operators" containing setsum, setprod,
  1205 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  1206 
  1207 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  1208 "Int" etc.  INCOMPATIBILITY.
  1209 
  1210 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  1211 
  1212 * New set of rules "ac_simps" provides combined assoc / commute
  1213 rewrites for all interpretations of the appropriate generic locales.
  1214 
  1215 * Renamed theory "OrderedGroup" to "Groups" and split theory
  1216 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  1217 appropriate and more consistent names suitable for name prefixes
  1218 within the HOL theories.  INCOMPATIBILITY.
  1219 
  1220 * Some generic constants have been put to appropriate theories:
  1221   - less_eq, less: Orderings
  1222   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  1223   - inverse, divide: Rings
  1224 INCOMPATIBILITY.
  1225 
  1226 * More consistent naming of type classes involving orderings (and
  1227 lattices):
  1228 
  1229     lower_semilattice                   ~> semilattice_inf
  1230     upper_semilattice                   ~> semilattice_sup
  1231 
  1232     dense_linear_order                  ~> dense_linorder
  1233 
  1234     pordered_ab_group_add               ~> ordered_ab_group_add
  1235     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  1236     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  1237     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  1238     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  1239     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  1240     pordered_cancel_semiring            ~> ordered_cancel_semiring
  1241     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  1242     pordered_comm_ring                  ~> ordered_comm_ring
  1243     pordered_comm_semiring              ~> ordered_comm_semiring
  1244     pordered_ring                       ~> ordered_ring
  1245     pordered_ring_abs                   ~> ordered_ring_abs
  1246     pordered_semiring                   ~> ordered_semiring
  1247 
  1248     ordered_ab_group_add                ~> linordered_ab_group_add
  1249     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  1250     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  1251     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  1252     ordered_field                       ~> linordered_field
  1253     ordered_field_no_lb                 ~> linordered_field_no_lb
  1254     ordered_field_no_ub                 ~> linordered_field_no_ub
  1255     ordered_field_dense_linear_order    ~> dense_linordered_field
  1256     ordered_idom                        ~> linordered_idom
  1257     ordered_ring                        ~> linordered_ring
  1258     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  1259     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  1260     ordered_ring_strict                 ~> linordered_ring_strict
  1261     ordered_semidom                     ~> linordered_semidom
  1262     ordered_semiring                    ~> linordered_semiring
  1263     ordered_semiring_1                  ~> linordered_semiring_1
  1264     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  1265     ordered_semiring_strict             ~> linordered_semiring_strict
  1266 
  1267   The following slightly odd type classes have been moved to a
  1268   separate theory Library/Lattice_Algebras:
  1269 
  1270     lordered_ab_group_add               ~> lattice_ab_group_add
  1271     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  1272     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  1273     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  1274     lordered_ring                       ~> lattice_ring
  1275 
  1276 INCOMPATIBILITY.
  1277 
  1278 * Refined field classes:
  1279   - classes division_ring_inverse_zero, field_inverse_zero,
  1280     linordered_field_inverse_zero include rule inverse 0 = 0 --
  1281     subsumes former division_by_zero class;
  1282   - numerous lemmas have been ported from field to division_ring.
  1283 INCOMPATIBILITY.
  1284 
  1285 * Refined algebra theorem collections:
  1286   - dropped theorem group group_simps, use algebra_simps instead;
  1287   - dropped theorem group ring_simps, use field_simps instead;
  1288   - proper theorem collection field_simps subsumes former theorem
  1289     groups field_eq_simps and field_simps;
  1290   - dropped lemma eq_minus_self_iff which is a duplicate for
  1291     equal_neg_zero.
  1292 INCOMPATIBILITY.
  1293 
  1294 * Theory Finite_Set and List: some lemmas have been generalized from
  1295 sets to lattices:
  1296 
  1297   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  1298   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  1299   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  1300   union_Union_fold_union        ~> sup_Sup_fold_sup
  1301   Inter_fold_inter              ~> Inf_fold_inf
  1302   Union_fold_union              ~> Sup_fold_sup
  1303   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  1304   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  1305   INTER_fold_inter              ~> INFI_fold_inf
  1306   UNION_fold_union              ~> SUPR_fold_sup
  1307 
  1308 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  1309 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  1310 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  1311 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  1312 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  1313 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  1314 
  1315 * Reorganized theory Multiset: swapped notation of pointwise and
  1316 multiset order:
  1317 
  1318   - pointwise ordering is instance of class order with standard syntax
  1319     <= and <;
  1320   - multiset ordering has syntax <=# and <#; partial order properties
  1321     are provided by means of interpretation with prefix
  1322     multiset_order;
  1323   - less duplication, less historical organization of sections,
  1324     conversion from associations lists to multisets, rudimentary code
  1325     generation;
  1326   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  1327     if needed.
  1328 
  1329 Renamed:
  1330 
  1331   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  1332   multi_count_ext  ~>  multiset_ext
  1333   diff_union_inverse2  ~>  diff_union_cancelR
  1334 
  1335 INCOMPATIBILITY.
  1336 
  1337 * Theory Permutation: replaced local "remove" by List.remove1.
  1338 
  1339 * Code generation: ML and OCaml code is decorated with signatures.
  1340 
  1341 * Theory List: added transpose.
  1342 
  1343 * Library/Nat_Bijection.thy is a collection of bijective functions
  1344 between nat and other types, which supersedes the older libraries
  1345 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  1346 
  1347   Constants:
  1348   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  1349   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  1350   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  1351   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  1352   Countable.pair_encode           ~> prod_encode
  1353   NatIso.prod2nat                 ~> prod_encode
  1354   NatIso.nat2prod                 ~> prod_decode
  1355   NatIso.sum2nat                  ~> sum_encode
  1356   NatIso.nat2sum                  ~> sum_decode
  1357   NatIso.list2nat                 ~> list_encode
  1358   NatIso.nat2list                 ~> list_decode
  1359   NatIso.set2nat                  ~> set_encode
  1360   NatIso.nat2set                  ~> set_decode
  1361 
  1362   Lemmas:
  1363   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  1364   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  1365   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  1366   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  1367   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  1368   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  1369   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  1370   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  1371   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  1372   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  1373   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  1374   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  1375   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  1376 
  1377 * Sledgehammer:
  1378   - Renamed ATP commands:
  1379     atp_info     ~> sledgehammer running_atps
  1380     atp_kill     ~> sledgehammer kill_atps
  1381     atp_messages ~> sledgehammer messages
  1382     atp_minimize ~> sledgehammer minimize
  1383     print_atps   ~> sledgehammer available_atps
  1384     INCOMPATIBILITY.
  1385   - Added user's manual ("isabelle doc sledgehammer").
  1386   - Added option syntax and "sledgehammer_params" to customize
  1387     Sledgehammer's behavior.  See the manual for details.
  1388   - Modified the Isar proof reconstruction code so that it produces
  1389     direct proofs rather than proofs by contradiction.  (This feature
  1390     is still experimental.)
  1391   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  1392     full-typed mode.
  1393   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  1394 
  1395 * Nitpick:
  1396   - Added and implemented "binary_ints" and "bits" options.
  1397   - Added "std" option and implemented support for nonstandard models.
  1398   - Added and implemented "finitize" option to improve the precision
  1399     of infinite datatypes based on a monotonicity analysis.
  1400   - Added support for quotient types.
  1401   - Added support for "specification" and "ax_specification"
  1402     constructs.
  1403   - Added support for local definitions (for "function" and
  1404     "termination" proofs).
  1405   - Added support for term postprocessors.
  1406   - Optimized "Multiset.multiset" and "FinFun.finfun".
  1407   - Improved efficiency of "destroy_constrs" optimization.
  1408   - Fixed soundness bugs related to "destroy_constrs" optimization and
  1409     record getters.
  1410   - Fixed soundness bug related to higher-order constructors.
  1411   - Fixed soundness bug when "full_descrs" is enabled.
  1412   - Improved precision of set constructs.
  1413   - Added "atoms" option.
  1414   - Added cache to speed up repeated Kodkod invocations on the same
  1415     problems.
  1416   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  1417     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  1418     "SAT4J_Light".  INCOMPATIBILITY.
  1419   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  1420     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  1421   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  1422 
  1423 * Method "induct" now takes instantiations of the form t, where t is not
  1424   a variable, as a shorthand for "x == t", where x is a fresh variable.
  1425   If this is not intended, t has to be enclosed in parentheses.
  1426   By default, the equalities generated by definitional instantiations
  1427   are pre-simplified, which may cause parameters of inductive cases
  1428   to disappear, or may even delete some of the inductive cases.
  1429   Use "induct (no_simp)" instead of "induct" to restore the old
  1430   behaviour. The (no_simp) option is also understood by the "cases"
  1431   and "nominal_induct" methods, which now perform pre-simplification, too.
  1432   INCOMPATIBILITY.
  1433 
  1434 
  1435 *** HOLCF ***
  1436 
  1437 * Variable names in lemmas generated by the domain package have
  1438 changed; the naming scheme is now consistent with the HOL datatype
  1439 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  1440 
  1441 * The domain package no longer defines the function "foo_copy" for
  1442 recursive domain "foo".  The reach lemma is now stated directly in
  1443 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  1444 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  1445 
  1446 * Most definedness lemmas generated by the domain package (previously
  1447 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  1448 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  1449 Proofs that used definedness lemmas as intro rules may break,
  1450 potential INCOMPATIBILITY.
  1451 
  1452 * Induction and casedist rules generated by the domain package now
  1453 declare proper case_names (one called "bottom", and one named for each
  1454 constructor).  INCOMPATIBILITY.
  1455 
  1456 * For mutually-recursive domains, separate "reach" and "take_lemma"
  1457 rules are generated for each domain, INCOMPATIBILITY.
  1458 
  1459   foo_bar.reach       ~> foo.reach  bar.reach
  1460   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  1461 
  1462 * Some lemmas generated by the domain package have been renamed for
  1463 consistency with the datatype package, INCOMPATIBILITY.
  1464 
  1465   foo.ind        ~> foo.induct
  1466   foo.finite_ind ~> foo.finite_induct
  1467   foo.coind      ~> foo.coinduct
  1468   foo.casedist   ~> foo.exhaust
  1469   foo.exhaust    ~> foo.nchotomy
  1470 
  1471 * For consistency with other definition packages, the fixrec package
  1472 now generates qualified theorem names, INCOMPATIBILITY.
  1473 
  1474   foo_simps  ~> foo.simps
  1475   foo_unfold ~> foo.unfold
  1476   foo_induct ~> foo.induct
  1477 
  1478 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  1479 method and internal fixrec proofs now use the default simpset instead.
  1480 INCOMPATIBILITY.
  1481 
  1482 * The "contlub" predicate has been removed.  Proof scripts should use
  1483 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  1484 
  1485 * The "admw" predicate has been removed, INCOMPATIBILITY.
  1486 
  1487 * The constants cpair, cfst, and csnd have been removed in favor of
  1488 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  1489 
  1490 
  1491 *** ML ***
  1492 
  1493 * Antiquotations for basic formal entities:
  1494 
  1495     @{class NAME}         -- type class
  1496     @{class_syntax NAME}  -- syntax representation of the above
  1497 
  1498     @{type_name NAME}     -- logical type
  1499     @{type_abbrev NAME}   -- type abbreviation
  1500     @{nonterminal NAME}   -- type of concrete syntactic category
  1501     @{type_syntax NAME}   -- syntax representation of any of the above
  1502 
  1503     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  1504     @{const_abbrev NAME}  -- abbreviated constant
  1505     @{const_syntax NAME}  -- syntax representation of any of the above
  1506 
  1507 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  1508 syntax constant (cf. 'syntax' command).
  1509 
  1510 * Antiquotation @{make_string} inlines a function to print arbitrary
  1511 values similar to the ML toplevel.  The result is compiler dependent
  1512 and may fall back on "?" in certain situations.
  1513 
  1514 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  1515 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  1516 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  1517 not work with the asynchronous Isar document model.
  1518 
  1519 * Configuration options now admit dynamic default values, depending on
  1520 the context or even global references.
  1521 
  1522 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  1523 uses an efficient external library if available (for Poly/ML).
  1524 
  1525 * Renamed some important ML structures, while keeping the old names
  1526 for some time as aliases within the structure Legacy:
  1527 
  1528   OuterKeyword  ~>  Keyword
  1529   OuterLex      ~>  Token
  1530   OuterParse    ~>  Parse
  1531   OuterSyntax   ~>  Outer_Syntax
  1532   PrintMode     ~>  Print_Mode
  1533   SpecParse     ~>  Parse_Spec
  1534   ThyInfo       ~>  Thy_Info
  1535   ThyLoad       ~>  Thy_Load
  1536   ThyOutput     ~>  Thy_Output
  1537   TypeInfer     ~>  Type_Infer
  1538 
  1539 Note that "open Legacy" simplifies porting of sources, but forgetting
  1540 to remove it again will complicate porting again in the future.
  1541 
  1542 * Most operations that refer to a global context are named
  1543 accordingly, e.g. Simplifier.global_context or
  1544 ProofContext.init_global.  There are some situations where a global
  1545 context actually works, but under normal circumstances one needs to
  1546 pass the proper local context through the code!
  1547 
  1548 * Discontinued old TheoryDataFun with its copy/init operation -- data
  1549 needs to be pure.  Functor Theory_Data_PP retains the traditional
  1550 Pretty.pp argument to merge, which is absent in the standard
  1551 Theory_Data version.
  1552 
  1553 * Sorts.certify_sort and derived "cert" operations for types and terms
  1554 no longer minimize sorts.  Thus certification at the boundary of the
  1555 inference kernel becomes invariant under addition of class relations,
  1556 which is an important monotonicity principle.  Sorts are now minimized
  1557 in the syntax layer only, at the boundary between the end-user and the
  1558 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  1559 explicitly in rare situations.
  1560 
  1561 * Renamed old-style Drule.standard to Drule.export_without_context, to
  1562 emphasize that this is in no way a standard operation.
  1563 INCOMPATIBILITY.
  1564 
  1565 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  1566 usual for resolution.  Rare INCOMPATIBILITY.
  1567 
  1568 * Renamed varify/unvarify operations to varify_global/unvarify_global
  1569 to emphasize that these only work in a global situation (which is
  1570 quite rare).
  1571 
  1572 * Curried take and drop in library.ML; negative length is interpreted
  1573 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  1574 
  1575 * Proof terms: type substitutions on proof constants now use canonical
  1576 order of type variables.  INCOMPATIBILITY for tools working with proof
  1577 terms.
  1578 
  1579 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  1580 may no longer carry premises.  User-level specifications are
  1581 transformed accordingly by Thm.add_axiom/add_def.
  1582 
  1583 
  1584 *** System ***
  1585 
  1586 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  1587 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  1588 proof terms are enabled unconditionally in the new HOL-Proofs image.
  1589 
  1590 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  1591 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  1592 respectively.
  1593 
  1594 * Old lib/scripts/polyml-platform is superseded by the
  1595 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  1596 variant, even on a 64 bit machine.  The following example setting
  1597 prefers 64 bit if available:
  1598 
  1599   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  1600 
  1601 * The preliminary Isabelle/jEdit application demonstrates the emerging
  1602 Isabelle/Scala layer for advanced prover interaction and integration.
  1603 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  1604 component.
  1605 
  1606 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  1607 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  1608 similar to the default assignment of the document preparation system
  1609 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  1610 provides some operations for direct access to the font without asking
  1611 the user for manual installation.
  1612 
  1613 
  1614 
  1615 New in Isabelle2009-1 (December 2009)
  1616 -------------------------------------
  1617 
  1618 *** General ***
  1619 
  1620 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  1621 one backslash should be used, even in ML sources.
  1622 
  1623 
  1624 *** Pure ***
  1625 
  1626 * Locale interpretation propagates mixins along the locale hierarchy.
  1627 The currently only available mixins are the equations used to map
  1628 local definitions to terms of the target domain of an interpretation.
  1629 
  1630 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  1631 loc" to print all interpretations of locale "loc" in the theory.
  1632 Interpretations in proofs are not shown.
  1633 
  1634 * Thoroughly revised locales tutorial.  New section on conditional
  1635 interpretation.
  1636 
  1637 * On instantiation of classes, remaining undefined class parameters
  1638 are formally declared.  INCOMPATIBILITY.
  1639 
  1640 
  1641 *** Document preparation ***
  1642 
  1643 * New generalized style concept for printing terms: @{foo (style) ...}
  1644 instead of @{foo_style style ...}  (old form is still retained for
  1645 backward compatibility).  Styles can be also applied for
  1646 antiquotations prop, term_type and typeof.
  1647 
  1648 
  1649 *** HOL ***
  1650 
  1651 * New proof method "smt" for a combination of first-order logic with
  1652 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  1653 fixed-size bitvectors; there is also basic support for higher-order
  1654 features (esp. lambda abstractions).  It is an incomplete decision
  1655 procedure based on external SMT solvers using the oracle mechanism;
  1656 for the SMT solver Z3, this method is proof-producing.  Certificates
  1657 are provided to avoid calling the external solvers solely for
  1658 re-checking proofs.  Due to a remote SMT service there is no need for
  1659 installing SMT solvers locally.  See src/HOL/SMT.
  1660 
  1661 * New commands to load and prove verification conditions generated by
  1662 the Boogie program verifier or derived systems (e.g. the Verifying C
  1663 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1664 
  1665 * New counterexample generator tool 'nitpick' based on the Kodkod
  1666 relational model finder.  See src/HOL/Tools/Nitpick and
  1667 src/HOL/Nitpick_Examples.
  1668 
  1669 * New commands 'code_pred' and 'values' to invoke the predicate
  1670 compiler and to enumerate values of inductive predicates.
  1671 
  1672 * A tabled implementation of the reflexive transitive closure.
  1673 
  1674 * New implementation of quickcheck uses generic code generator;
  1675 default generators are provided for all suitable HOL types, records
  1676 and datatypes.  Old quickcheck can be re-activated importing theory
  1677 Library/SML_Quickcheck.
  1678 
  1679 * New testing tool Mirabelle for automated proof tools.  Applies
  1680 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1681 every proof step in a theory.  To be used in batch mode via the
  1682 "mirabelle" utility.
  1683 
  1684 * New proof method "sos" (sum of squares) for nonlinear real
  1685 arithmetic (originally due to John Harison). It requires theory
  1686 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1687 works well in practice on quantifier-free real arithmetic with +, -,
  1688 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1689 inequalities between polynomials.  It makes use of external
  1690 semidefinite programming solvers.  Method "sos" generates a
  1691 certificate that can be pasted into the proof thus avoiding the need
  1692 to call an external tool every time the proof is checked.  See
  1693 src/HOL/Library/Sum_Of_Squares.
  1694 
  1695 * New method "linarith" invokes existing linear arithmetic decision
  1696 procedure only.
  1697 
  1698 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1699 
  1700 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1701 Causes full type information to be output to the ATPs.  This slows
  1702 ATPs down considerably but eliminates a source of unsound "proofs"
  1703 that fail later.
  1704 
  1705 * New method "metisFT": A version of metis that uses full type
  1706 information in order to avoid failures of proof reconstruction.
  1707 
  1708 * New evaluator "approximate" approximates an real valued term using
  1709 the same method as the approximation method.
  1710 
  1711 * Method "approximate" now supports arithmetic expressions as
  1712 boundaries of intervals and implements interval splitting and Taylor
  1713 series expansion.
  1714 
  1715 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1716 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1717 
  1718 * New theory SupInf of the supremum and infimum operators for sets of
  1719 reals.
  1720 
  1721 * New theory Probability, which contains a development of measure
  1722 theory, eventually leading to Lebesgue integration and probability.
  1723 
  1724 * Extended Multivariate Analysis to include derivation and Brouwer's
  1725 fixpoint theorem.
  1726 
  1727 * Reorganization of number theory, INCOMPATIBILITY:
  1728   - new number theory development for nat and int, in theories Divides
  1729     and GCD as well as in new session Number_Theory
  1730   - some constants and facts now suffixed with _nat and _int
  1731     accordingly
  1732   - former session NumberTheory now named Old_Number_Theory, including
  1733     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1734   - moved theory Pocklington from src/HOL/Library to
  1735     src/HOL/Old_Number_Theory
  1736 
  1737 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1738 lcm of finite and infinite sets. It is shown that they form a complete
  1739 lattice.
  1740 
  1741 * Class semiring_div requires superclass no_zero_divisors and proof of
  1742 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1743 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1744 generalized to class semiring_div, subsuming former theorems
  1745 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1746 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1747 INCOMPATIBILITY.
  1748 
  1749 * Refinements to lattice classes and sets:
  1750   - less default intro/elim rules in locale variant, more default
  1751     intro/elim rules in class variant: more uniformity
  1752   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1753     le_inf_iff
  1754   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1755     sup_aci)
  1756   - renamed ACI to inf_sup_aci
  1757   - new class "boolean_algebra"
  1758   - class "complete_lattice" moved to separate theory
  1759     "Complete_Lattice"; corresponding constants (and abbreviations)
  1760     renamed and with authentic syntax:
  1761     Set.Inf ~>    Complete_Lattice.Inf
  1762     Set.Sup ~>    Complete_Lattice.Sup
  1763     Set.INFI ~>   Complete_Lattice.INFI
  1764     Set.SUPR ~>   Complete_Lattice.SUPR
  1765     Set.Inter ~>  Complete_Lattice.Inter
  1766     Set.Union ~>  Complete_Lattice.Union
  1767     Set.INTER ~>  Complete_Lattice.INTER
  1768     Set.UNION ~>  Complete_Lattice.UNION
  1769   - authentic syntax for
  1770     Set.Pow
  1771     Set.image
  1772   - mere abbreviations:
  1773     Set.empty               (for bot)
  1774     Set.UNIV                (for top)
  1775     Set.inter               (for inf, formerly Set.Int)
  1776     Set.union               (for sup, formerly Set.Un)
  1777     Complete_Lattice.Inter  (for Inf)
  1778     Complete_Lattice.Union  (for Sup)
  1779     Complete_Lattice.INTER  (for INFI)
  1780     Complete_Lattice.UNION  (for SUPR)
  1781   - object-logic definitions as far as appropriate
  1782 
  1783 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1784 Un_subset_iff are explicitly deleted as default simp rules; then also
  1785 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1786 deleted to achieve the desired effect.
  1787 
  1788 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1789 rules by default any longer; the same applies to min_max.inf_absorb1
  1790 etc.  INCOMPATIBILITY.
  1791 
  1792 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1793 pred_set_conv by default.  INCOMPATIBILITY.
  1794 
  1795 * Power operations on relations and functions are now one dedicated
  1796 constant "compow" with infix syntax "^^".  Power operation on
  1797 multiplicative monoids retains syntax "^" and is now defined generic
  1798 in class power.  INCOMPATIBILITY.
  1799 
  1800 * Relation composition "R O S" now has a more standard argument order:
  1801 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1802 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1803 break, since the O_assoc rule was not rewritten like this.  Fix using
  1804 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1805 
  1806 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1807 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1808 INCOMPATIBILITY.
  1809 
  1810 * Most rules produced by inductive and datatype package have mandatory
  1811 prefixes.  INCOMPATIBILITY.
  1812 
  1813 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1814 the attribute of the same name.  Each of the theorems in the list
  1815 DERIV_intros assumes composition with an additional function and
  1816 matches a variable to the derivative, which has to be solved by the
  1817 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1818 of most elementary terms.  Former Maclauren.DERIV_tac and
  1819 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1820 INCOMPATIBILITY.
  1821 
  1822 * Code generator attributes follow the usual underscore convention:
  1823     code_unfold     replaces    code unfold
  1824     code_post       replaces    code post
  1825     etc.
  1826   INCOMPATIBILITY.
  1827 
  1828 * Renamed methods:
  1829     sizechange -> size_change
  1830     induct_scheme -> induction_schema
  1831   INCOMPATIBILITY.
  1832 
  1833 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1834 INCOMPATIBILITY, use "undefined" directly.
  1835 
  1836 * Renamed theorems:
  1837     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1838     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1839     Suc_plus1 -> Suc_eq_plus1
  1840     *anti_sym -> *antisym*
  1841     vector_less_eq_def -> vector_le_def
  1842   INCOMPATIBILITY.
  1843 
  1844 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1845 INCOMPATIBILITY.
  1846 
  1847 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1848 INCOMPATIBILITY.
  1849 
  1850 
  1851 *** HOLCF ***
  1852 
  1853 * Theory Representable defines a class "rep" of domains that are
  1854 representable (via an ep-pair) in the universal domain type "udom".
  1855 Instances are provided for all type constructors defined in HOLCF.
  1856 
  1857 * The 'new_domain' command is a purely definitional version of the
  1858 domain package, for representable domains.  Syntax is identical to the
  1859 old domain package.  The 'new_domain' package also supports indirect
  1860 recursion using previously-defined type constructors.  See
  1861 src/HOLCF/ex/New_Domain.thy for examples.
  1862 
  1863 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1864 on the left-hand side of an equation, and then performs
  1865 simplification.  Rewriting is done using rules declared with the
  1866 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1867 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1868 
  1869 * The pattern-match compiler in 'fixrec' can now handle constructors
  1870 with HOL function types.  Pattern-match combinators for the Pair
  1871 constructor are pre-configured.
  1872 
  1873 * The 'fixrec' package now produces better fixed-point induction rules
  1874 for mutually-recursive definitions:  Induction rules have conclusions
  1875 of the form "P foo bar" instead of "P <foo, bar>".
  1876 
  1877 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1878 been renamed to "below".  The name "below" now replaces "less" in many
  1879 theorem names.  (Legacy theorem names using "less" are still supported
  1880 as well.)
  1881 
  1882 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1883 patterns can be used to generate strictness rules, or to make
  1884 functions more strict (much like the bang-patterns supported by the
  1885 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1886 examples.
  1887 
  1888 
  1889 *** ML ***
  1890 
  1891 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1892 errors and run-time exceptions, including detailed source positions.
  1893 
  1894 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1895 identified entries, with some additional information such as source
  1896 position, logical grouping etc.
  1897 
  1898 * Theory and context data is now introduced by the simplified and
  1899 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1900 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1901 copy operation) is still available for some time.
  1902 
  1903 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1904 provides a high-level programming interface to synchronized state
  1905 variables with atomic update.  This works via pure function
  1906 application within a critical section -- its runtime should be as
  1907 short as possible; beware of deadlocks if critical code is nested,
  1908 either directly or indirectly via other synchronized variables!
  1909 
  1910 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1911 wraps raw ML references, explicitly indicating their non-thread-safe
  1912 behaviour.  The Isar toplevel keeps this structure open, to
  1913 accommodate Proof General as well as quick and dirty interactive
  1914 experiments with references.
  1915 
  1916 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1917 parallel tactical reasoning.
  1918 
  1919 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1920 are similar to SUBPROOF, but are slightly more flexible: only the
  1921 specified parts of the subgoal are imported into the context, and the
  1922 body tactic may introduce new subgoals and schematic variables.
  1923 
  1924 * Old tactical METAHYPS, which does not observe the proof context, has
  1925 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1926 or Subgoal.FOCUS etc.
  1927 
  1928 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  1929 functors have their own ML name space there is no point to mark them
  1930 separately.)  Minor INCOMPATIBILITY.
  1931 
  1932 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  1933 
  1934 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  1935 INCOMPATIBILITY.
  1936 
  1937 * Operations of structure Skip_Proof no longer require quick_and_dirty
  1938 mode, which avoids critical setmp.
  1939 
  1940 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  1941 combinators for "args".  INCOMPATIBILITY, need to use simplified
  1942 Attrib/Method.setup introduced in Isabelle2009.
  1943 
  1944 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  1945 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  1946 last resort.  INCOMPATIBILITY.
  1947 
  1948 * Display.pretty_thm now requires a proper context (cf. former
  1949 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  1950 or even Display.pretty_thm_without_context as last resort.
  1951 INCOMPATIBILITY.
  1952 
  1953 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  1954 Syntax.pretty_typ/term directly, preferably with proper context
  1955 instead of global theory.
  1956 
  1957 
  1958 *** System ***
  1959 
  1960 * Further fine tuning of parallel proof checking, scales up to 8 cores
  1961 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  1962 usedir option -q.
  1963 
  1964 * Support for additional "Isabelle components" via etc/components, see
  1965 also the system manual.
  1966 
  1967 * The isabelle makeall tool now operates on all components with
  1968 IsaMakefile, not just hardwired "logics".
  1969 
  1970 * Removed "compress" option from isabelle-process and isabelle usedir;
  1971 this is always enabled.
  1972 
  1973 * Discontinued support for Poly/ML 4.x versions.
  1974 
  1975 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  1976 on a given logic image.  This requires the lighttpd webserver and is
  1977 currently supported on Linux only.
  1978 
  1979 
  1980 
  1981 New in Isabelle2009 (April 2009)
  1982 --------------------------------
  1983 
  1984 *** General ***
  1985 
  1986 * Simplified main Isabelle executables, with less surprises on
  1987 case-insensitive file-systems (such as Mac OS).
  1988 
  1989   - The main Isabelle tool wrapper is now called "isabelle" instead of
  1990     "isatool."
  1991 
  1992   - The former "isabelle" alias for "isabelle-process" has been
  1993     removed (should rarely occur to regular users).
  1994 
  1995   - The former "isabelle-interface" and its alias "Isabelle" have been
  1996     removed (interfaces are now regular Isabelle tools).
  1997 
  1998 Within scripts and make files, the Isabelle environment variables
  1999 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  2000 respectively.  (The latter are still available as legacy feature.)
  2001 
  2002 The old isabelle-interface wrapper could react in confusing ways if
  2003 the interface was uninstalled or changed otherwise.  Individual
  2004 interface tool configuration is now more explicit, see also the
  2005 Isabelle system manual.  In particular, Proof General is now available
  2006 via "isabelle emacs".
  2007 
  2008 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  2009 purge installed copies of Isabelle executables and re-run "isabelle
  2010 install -p ...", or use symlinks.
  2011 
  2012 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  2013 old ~/isabelle, which was slightly non-standard and apt to cause
  2014 surprises on case-insensitive file-systems (such as Mac OS).
  2015 
  2016 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  2017 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  2018 care is required when using older releases of Isabelle.  Note that
  2019 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  2020 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  2021 
  2022 * Proofs of fully specified statements are run in parallel on
  2023 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  2024 a regular 4-core machine, if the initial heap space is made reasonably
  2025 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  2026 
  2027 * The main reference manuals ("isar-ref", "implementation", and
  2028 "system") have been updated and extended.  Formally checked references
  2029 as hyperlinks are now available uniformly.
  2030 
  2031 
  2032 *** Pure ***
  2033 
  2034 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  2035 respects.  The most important changes are listed below.  See the
  2036 Tutorial on Locales ("locales" manual) for details.
  2037 
  2038 - In locale expressions, instantiation replaces renaming.  Parameters
  2039 must be declared in a for clause.  To aid compatibility with previous
  2040 parameter inheritance, in locale declarations, parameters that are not
  2041 'touched' (instantiation position "_" or omitted) are implicitly added
  2042 with their syntax at the beginning of the for clause.
  2043 
  2044 - Syntax from abbreviations and definitions in locales is available in
  2045 locale expressions and context elements.  The latter is particularly
  2046 useful in locale declarations.
  2047 
  2048 - More flexible mechanisms to qualify names generated by locale
  2049 expressions.  Qualifiers (prefixes) may be specified in locale
  2050 expressions, and can be marked as mandatory (syntax: "name!:") or
  2051 optional (syntax "name?:").  The default depends for plain "name:"
  2052 depends on the situation where a locale expression is used: in
  2053 commands 'locale' and 'sublocale' prefixes are optional, in
  2054 'interpretation' and 'interpret' prefixes are mandatory.  The old
  2055 implicit qualifiers derived from the parameter names of a locale are
  2056 no longer generated.
  2057 
  2058 - Command "sublocale l < e" replaces "interpretation l < e".  The
  2059 instantiation clause in "interpretation" and "interpret" (square
  2060 brackets) is no longer available.  Use locale expressions.
  2061 
  2062 - When converting proof scripts, mandatory qualifiers in
  2063 'interpretation' and 'interpret' should be retained by default, even
  2064 if this is an INCOMPATIBILITY compared to former behavior.  In the
  2065 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  2066 in locale expressions range over a single locale instance only.
  2067 
  2068 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  2069 In existing theorem specifications replace the includes element by the
  2070 respective context elements of the included locale, omitting those
  2071 that are already present in the theorem specification.  Multiple
  2072 assume elements of a locale should be replaced by a single one
  2073 involving the locale predicate.  In the proof body, declarations (most
  2074 notably theorems) may be regained by interpreting the respective
  2075 locales in the proof context as required (command "interpret").
  2076 
  2077 If using "includes" in replacement of a target solely because the
  2078 parameter types in the theorem are not as general as in the target,
  2079 consider declaring a new locale with additional type constraints on
  2080 the parameters (context element "constrains").
  2081 
  2082 - Discontinued "locale (open)".  INCOMPATIBILITY.
  2083 
  2084 - Locale interpretation commands no longer attempt to simplify goal.
  2085 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  2086 methods intro_locales and unfold_locales to clarify.
  2087 
  2088 - Locale interpretation commands no longer accept interpretation
  2089 attributes.  INCOMPATIBILITY.
  2090 
  2091 * Class declaration: so-called "base sort" must not be given in import
  2092 list any longer, but is inferred from the specification.  Particularly
  2093 in HOL, write
  2094 
  2095     class foo = ...
  2096 
  2097 instead of
  2098 
  2099     class foo = type + ...
  2100 
  2101 * Class target: global versions of theorems stemming do not carry a
  2102 parameter prefix any longer.  INCOMPATIBILITY.
  2103 
  2104 * Class 'instance' command no longer accepts attached definitions.
  2105 INCOMPATIBILITY, use proper 'instantiation' target instead.
  2106 
  2107 * Recovered hiding of consts, which was accidentally broken in
  2108 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  2109 makes c inaccessible; consider using ``hide (open) const c'' instead.
  2110 
  2111 * Slightly more coherent Pure syntax, with updated documentation in
  2112 isar-ref manual.  Removed locales meta_term_syntax and
  2113 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  2114 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  2115 directly in regular applications.
  2116 
  2117 * There is a new syntactic category "float_const" for signed decimal
  2118 fractions (e.g. 123.45 or -123.45).
  2119 
  2120 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  2121 interface with 'setup' command instead.
  2122 
  2123 * Command 'local_setup' is similar to 'setup', but operates on a local
  2124 theory context.
  2125 
  2126 * The 'axiomatization' command now only works within a global theory
  2127 context.  INCOMPATIBILITY.
  2128 
  2129 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  2130 hypotheses.  Sorts required in the course of reasoning need to be
  2131 covered by the constraints in the initial statement, completed by the
  2132 type instance information of the background theory.  Non-trivial sort
  2133 hypotheses, which rarely occur in practice, may be specified via
  2134 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  2135 
  2136   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  2137 
  2138 The result contains an implicit sort hypotheses as before --
  2139 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  2140 normalization.
  2141 
  2142 * Generalized Isar history, with support for linear undo, direct state
  2143 addressing etc.
  2144 
  2145 * Changed defaults for unify configuration options:
  2146 
  2147   unify_trace_bound = 50 (formerly 25)
  2148   unify_search_bound = 60 (formerly 30)
  2149 
  2150 * Different bookkeeping for code equations (INCOMPATIBILITY):
  2151 
  2152   a) On theory merge, the last set of code equations for a particular
  2153      constant is taken (in accordance with the policy applied by other
  2154      parts of the code generator framework).
  2155 
  2156   b) Code equations stemming from explicit declarations (e.g. code
  2157      attribute) gain priority over default code equations stemming
  2158      from definition, primrec, fun etc.
  2159 
  2160 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  2161 
  2162 * Unified theorem tables for both code generators.  Thus [code
  2163 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  2164 
  2165 * Command 'find_consts' searches for constants based on type and name
  2166 patterns, e.g.
  2167 
  2168     find_consts "_ => bool"
  2169 
  2170 By default, matching is against subtypes, but it may be restricted to
  2171 the whole type.  Searching by name is possible.  Multiple queries are
  2172 conjunctive and queries may be negated by prefixing them with a
  2173 hyphen:
  2174 
  2175     find_consts strict: "_ => bool" name: "Int" -"int => int"
  2176 
  2177 * New 'find_theorems' criterion "solves" matches theorems that
  2178 directly solve the current goal (modulo higher-order unification).
  2179 
  2180 * Auto solve feature for main theorem statements: whenever a new goal
  2181 is stated, "find_theorems solves" is called; any theorems that could
  2182 solve the lemma directly are listed as part of the goal state.
  2183 Cf. associated options in Proof General Isabelle settings menu,
  2184 enabled by default, with reasonable timeout for pathological cases of
  2185 higher-order unification.
  2186 
  2187 
  2188 *** Document preparation ***
  2189 
  2190 * Antiquotation @{lemma} now imitates a regular terminal proof,
  2191 demanding keyword 'by' and supporting the full method expression
  2192 syntax just like the Isar command 'by'.
  2193 
  2194 
  2195 *** HOL ***
  2196 
  2197 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  2198 points Main and Complex_Main remain as before.
  2199 
  2200 * Logic image HOL-Plain provides a minimal HOL with the most important
  2201 tools available (inductive, datatype, primrec, ...).  This facilitates
  2202 experimentation and tool development.  Note that user applications
  2203 (and library theories) should never refer to anything below theory
  2204 Main, as before.
  2205 
  2206 * Logic image HOL-Main stops at theory Main, and thus facilitates
  2207 experimentation due to shorter build times.
  2208 
  2209 * Logic image HOL-NSA contains theories of nonstandard analysis which
  2210 were previously part of former HOL-Complex.  Entry point Hyperreal
  2211 remains valid, but theories formerly using Complex_Main should now use
  2212 new entry point Hypercomplex.
  2213 
  2214 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  2215 Posix processes.  Avoids potentially expensive forking of the ML
  2216 process.  New thread-based implementation also works on non-Unix
  2217 platforms (Cygwin).  Provers are no longer hardwired, but defined
  2218 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  2219 commands are covered in the isar-ref manual.
  2220 
  2221 * Wrapper scripts for remote SystemOnTPTP service allows to use
  2222 sledgehammer without local ATP installation (Vampire etc.). Other
  2223 provers may be included via suitable ML wrappers, see also
  2224 src/HOL/ATP_Linkup.thy.
  2225 
  2226 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  2227 menu.
  2228 
  2229 * The metis method no longer fails because the theorem is too trivial
  2230 (contains the empty clause).
  2231 
  2232 * The metis method now fails in the usual manner, rather than raising
  2233 an exception, if it determines that it cannot prove the theorem.
  2234 
  2235 * Method "coherent" implements a prover for coherent logic (see also
  2236 src/Tools/coherent.ML).
  2237 
  2238 * Constants "undefined" and "default" replace "arbitrary".  Usually
  2239 "undefined" is the right choice to replace "arbitrary", though
  2240 logically there is no difference.  INCOMPATIBILITY.
  2241 
  2242 * Command "value" now integrates different evaluation mechanisms.  The
  2243 result of the first successful evaluation mechanism is printed.  In
  2244 square brackets a particular named evaluation mechanisms may be
  2245 specified (currently, [SML], [code] or [nbe]).  See further
  2246 src/HOL/ex/Eval_Examples.thy.
  2247 
  2248 * Normalization by evaluation now allows non-leftlinear equations.
  2249 Declare with attribute [code nbe].
  2250 
  2251 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  2252 as the structured Isar versions "cases" and "induct", cf. the
  2253 corresponding "cases" and "induct" attributes.  Mutual induction rules
  2254 are now presented as a list of individual projections
  2255 (e.g. foo_bar.inducts for types foo and bar); the old format with
  2256 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  2257 rare situations a different rule is selected --- notably nested tuple
  2258 elimination instead of former prod.exhaust: use explicit (case_tac t
  2259 rule: prod.exhaust) here.
  2260 
  2261 * Attributes "cases", "induct", "coinduct" support "del" option.
  2262 
  2263 * Removed fact "case_split_thm", which duplicates "case_split".
  2264 
  2265 * The option datatype has been moved to a new theory Option.  Renamed
  2266 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  2267 
  2268 * New predicate "strict_mono" classifies strict functions on partial
  2269 orders.  With strict functions on linear orders, reasoning about
  2270 (in)equalities is facilitated by theorems "strict_mono_eq",
  2271 "strict_mono_less_eq" and "strict_mono_less".
  2272 
  2273 * Some set operations are now proper qualified constants with
  2274 authentic syntax.  INCOMPATIBILITY:
  2275 
  2276     op Int ~>   Set.Int
  2277     op Un ~>    Set.Un
  2278     INTER ~>    Set.INTER
  2279     UNION ~>    Set.UNION
  2280     Inter ~>    Set.Inter
  2281     Union ~>    Set.Union
  2282     {} ~>       Set.empty
  2283     UNIV ~>     Set.UNIV
  2284 
  2285 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  2286 theory Set.
  2287 
  2288 * Auxiliary class "itself" has disappeared -- classes without any
  2289 parameter are treated as expected by the 'class' command.
  2290 
  2291 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  2292 
  2293 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  2294 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  2295 
  2296 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  2297 method "approximation".  It proves formulas on real values by using
  2298 interval arithmetic.  In the formulas are also the transcendental
  2299 functions sin, cos, tan, atan, ln, exp and the constant pi are
  2300 allowed. For examples see
  2301 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  2302 
  2303 * Theory "Reflection" now resides in HOL/Library.
  2304 
  2305 * Entry point to Word library now simply named "Word".
  2306 INCOMPATIBILITY.
  2307 
  2308 * Made source layout more coherent with logical distribution
  2309 structure:
  2310 
  2311     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  2312     src/HOL/Library/Code_Message.thy ~> src/HOL/
  2313     src/HOL/Library/GCD.thy ~> src/HOL/
  2314     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  2315     src/HOL/Library/Parity.thy ~> src/HOL/
  2316     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  2317     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  2318     src/HOL/Real/Lubs.thy ~> src/HOL/
  2319     src/HOL/Real/PReal.thy ~> src/HOL/
  2320     src/HOL/Real/Rational.thy ~> src/HOL/
  2321     src/HOL/Real/RComplete.thy ~> src/HOL/
  2322     src/HOL/Real/RealDef.thy ~> src/HOL/
  2323     src/HOL/Real/RealPow.thy ~> src/HOL/
  2324     src/HOL/Real/Real.thy ~> src/HOL/
  2325     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  2326     src/HOL/Complex/Complex.thy ~> src/HOL/
  2327     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  2328     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  2329     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  2330     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  2331     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  2332     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  2333     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  2334     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  2335     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  2336     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  2337     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  2338     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  2339     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  2340     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  2341     src/HOL/Real/Float ~> src/HOL/Library/
  2342     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  2343     src/HOL/Real/RealVector.thy ~> src/HOL/
  2344 
  2345     src/HOL/arith_data.ML ~> src/HOL/Tools
  2346     src/HOL/hologic.ML ~> src/HOL/Tools
  2347     src/HOL/simpdata.ML ~> src/HOL/Tools
  2348     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  2349     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  2350     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  2351     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  2352     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  2353     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  2354     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  2355 
  2356     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  2357     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  2358     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  2359     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  2360     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  2361     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  2362 
  2363 * If methods "eval" and "evaluation" encounter a structured proof
  2364 state with !!/==>, only the conclusion is evaluated to True (if
  2365 possible), avoiding strange error messages.
  2366 
  2367 * Method "sizechange" automates termination proofs using (a
  2368 modification of) the size-change principle.  Requires SAT solver.  See
  2369 src/HOL/ex/Termination.thy for examples.
  2370 
  2371 * Simplifier: simproc for let expressions now unfolds if bound
  2372 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  2373 
  2374 * Method "arith": Linear arithmetic now ignores all inequalities when
  2375 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  2376 
  2377 * New attribute "arith" for facts that should always be used
  2378 automatically by arithmetic. It is intended to be used locally in
  2379 proofs, e.g.
  2380 
  2381   assumes [arith]: "x > 0"
  2382 
  2383 Global usage is discouraged because of possible performance impact.
  2384 
  2385 * New classes "top" and "bot" with corresponding operations "top" and
  2386 "bot" in theory Orderings; instantiation of class "complete_lattice"
  2387 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  2388 
  2389 * Changed definition lemma "less_fun_def" in order to provide an
  2390 instance for preorders on functions; use lemma "less_le" instead.
  2391 INCOMPATIBILITY.
  2392 
  2393 * Theory Orderings: class "wellorder" moved here, with explicit
  2394 induction rule "less_induct" as assumption.  For instantiation of
  2395 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  2396 INCOMPATIBILITY.
  2397 
  2398 * Theory Orderings: added class "preorder" as superclass of "order".
  2399 INCOMPATIBILITY: Instantiation proofs for order, linorder
  2400 etc. slightly changed.  Some theorems named order_class.* now named
  2401 preorder_class.*.
  2402 
  2403 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  2404 "diag" to "Id_on".
  2405 
  2406 * Theory Finite_Set: added a new fold combinator of type
  2407 
  2408   ('a => 'b => 'b) => 'b => 'a set => 'b
  2409 
  2410 Occasionally this is more convenient than the old fold combinator
  2411 which is now defined in terms of the new one and renamed to
  2412 fold_image.
  2413 
  2414 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  2415 and "ring_simps" have been replaced by "algebra_simps" (which can be
  2416 extended with further lemmas!).  At the moment both still exist but
  2417 the former will disappear at some point.
  2418 
  2419 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  2420 class recpower.  Type-specific simp rules for various recpower types
  2421 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  2422 
  2423 rat_power_0    -> power_0
  2424 rat_power_Suc  -> power_Suc
  2425 realpow_0      -> power_0
  2426 realpow_Suc    -> power_Suc
  2427 complexpow_0   -> power_0
  2428 complexpow_Suc -> power_Suc
  2429 power_poly_0   -> power_0
  2430 power_poly_Suc -> power_Suc
  2431 
  2432 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  2433 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  2434 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  2435 of lemmas from Divides has been generalized from nat to class
  2436 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  2437 renames resulting from duplicate elimination:
  2438 
  2439     dvd_def_mod ~>          dvd_eq_mod_eq_0
  2440     zero_dvd_iff ~>         dvd_0_left_iff
  2441     dvd_0 ~>                dvd_0_right
  2442     DIVISION_BY_ZERO_DIV ~> div_by_0
  2443     DIVISION_BY_ZERO_MOD ~> mod_by_0
  2444     mult_div ~>             div_mult_self2_is_id
  2445     mult_mod ~>             mod_mult_self2_is_0
  2446 
  2447 * Theory IntDiv: removed many lemmas that are instances of class-based
  2448 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  2449 rename old lemmas as follows:
  2450 
  2451 dvd_diff               -> nat_dvd_diff
  2452 dvd_zminus_iff         -> dvd_minus_iff
  2453 mod_add1_eq            -> mod_add_eq
  2454 mod_mult1_eq           -> mod_mult_right_eq
  2455 mod_mult1_eq'          -> mod_mult_left_eq
  2456 mod_mult_distrib_mod   -> mod_mult_eq
  2457 nat_mod_add_left_eq    -> mod_add_left_eq
  2458 nat_mod_add_right_eq   -> mod_add_right_eq
  2459 nat_mod_div_trivial    -> mod_div_trivial
  2460 nat_mod_mod_trivial    -> mod_mod_trivial
  2461 zdiv_zadd_self1        -> div_add_self1
  2462 zdiv_zadd_self2        -> div_add_self2
  2463 zdiv_zmult_self1       -> div_mult_self2_is_id
  2464 zdiv_zmult_self2       -> div_mult_self1_is_id
  2465 zdvd_triv_left         -> dvd_triv_left
  2466 zdvd_triv_right        -> dvd_triv_right
  2467 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  2468 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  2469 zmod_zadd_left_eq      -> mod_add_left_eq
  2470 zmod_zadd_right_eq     -> mod_add_right_eq
  2471 zmod_zadd_self1        -> mod_add_self1
  2472 zmod_zadd_self2        -> mod_add_self2
  2473 zmod_zadd1_eq          -> mod_add_eq
  2474 zmod_zdiff1_eq         -> mod_diff_eq
  2475 zmod_zdvd_zmod         -> mod_mod_cancel
  2476 zmod_zmod_cancel       -> mod_mod_cancel
  2477 zmod_zmult_self1       -> mod_mult_self2_is_0
  2478 zmod_zmult_self2       -> mod_mult_self1_is_0
  2479 zmod_1                 -> mod_by_1
  2480 zdiv_1                 -> div_by_1
  2481 zdvd_abs1              -> abs_dvd_iff
  2482 zdvd_abs2              -> dvd_abs_iff
  2483 zdvd_refl              -> dvd_refl
  2484 zdvd_trans             -> dvd_trans
  2485 zdvd_zadd              -> dvd_add
  2486 zdvd_zdiff             -> dvd_diff
  2487 zdvd_zminus_iff        -> dvd_minus_iff
  2488 zdvd_zminus2_iff       -> minus_dvd_iff
  2489 zdvd_zmultD            -> dvd_mult_right
  2490 zdvd_zmultD2           -> dvd_mult_left
  2491 zdvd_zmult_mono        -> mult_dvd_mono
  2492 zdvd_0_right           -> dvd_0_right
  2493 zdvd_0_left            -> dvd_0_left_iff
  2494 zdvd_1_left            -> one_dvd
  2495 zminus_dvd_iff         -> minus_dvd_iff
  2496 
  2497 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  2498 
  2499 * The real numbers offer decimal input syntax: 12.34 is translated
  2500 into 1234/10^2. This translation is not reversed upon output.
  2501 
  2502 * Theory Library/Polynomial defines an abstract type 'a poly of
  2503 univariate polynomials with coefficients of type 'a.  In addition to
  2504 the standard ring operations, it also supports div and mod.  Code
  2505 generation is also supported, using list-style constructors.
  2506 
  2507 * Theory Library/Inner_Product defines a class of real_inner for real
  2508 inner product spaces, with an overloaded operation inner :: 'a => 'a
  2509 => real.  Class real_inner is a subclass of real_normed_vector from
  2510 theory RealVector.
  2511 
  2512 * Theory Library/Product_Vector provides instances for the product
  2513 type 'a * 'b of several classes from RealVector and Inner_Product.
  2514 Definitions of addition, subtraction, scalar multiplication, norms,
  2515 and inner products are included.
  2516 
  2517 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  2518 addition to the field operations, numerals and case syntax are also
  2519 supported.
  2520 
  2521 * Theory Library/Diagonalize provides constructive version of Cantor's
  2522 first diagonalization argument.
  2523 
  2524 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  2525 zlcm (for int); carried together from various gcd/lcm developements in
  2526 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  2527 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  2528 may recover tupled syntax as follows:
  2529 
  2530     hide (open) const gcd
  2531     abbreviation gcd where
  2532       "gcd == (%(a, b). GCD.gcd a b)"
  2533     notation (output)
  2534       GCD.gcd ("gcd '(_, _')")
  2535 
  2536 The same works for lcm, zgcd, zlcm.
  2537 
  2538 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  2539 instantiations for algebraic structures.  Removed some duplicate
  2540 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  2541 
  2542 * ML antiquotation @{code} takes a constant as argument and generates
  2543 corresponding code in background and inserts name of the corresponding
  2544 resulting ML value/function/datatype constructor binding in place.
  2545 All occurrences of @{code} with a single ML block are generated
  2546 simultaneously.  Provides a generic and safe interface for
  2547 instrumentalizing code generation.  See
  2548 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  2549 In future you ought to refrain from ad-hoc compiling generated SML
  2550 code on the ML toplevel.  Note that (for technical reasons) @{code}
  2551 cannot refer to constants for which user-defined serializations are
  2552 set.  Refer to the corresponding ML counterpart directly in that
  2553 cases.
  2554 
  2555 * Command 'rep_datatype': instead of theorem names the command now
  2556 takes a list of terms denoting the constructors of the type to be
  2557 represented as datatype.  The characteristic theorems have to be
  2558 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  2559 have disappeared in favour of existing ones:
  2560 
  2561     unit_induct                 ~> unit.induct
  2562     prod_induct                 ~> prod.induct
  2563     sum_induct                  ~> sum.induct
  2564     Suc_Suc_eq                  ~> nat.inject
  2565     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  2566 
  2567 
  2568 *** HOL-Algebra ***
  2569 
  2570 * New locales for orders and lattices where the equivalence relation
  2571 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  2572 locales use a record structure with field eq for the equivalence.
  2573 
  2574 * New theory of factorial domains.
  2575 
  2576 * Units_l_inv and Units_r_inv are now simp rules by default.
  2577 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  2578 and/or r_inv will now also require deletion of these lemmas.
  2579 
  2580 * Renamed the following theorems, INCOMPATIBILITY:
  2581 
  2582 UpperD ~> Upper_memD
  2583 LowerD ~> Lower_memD
  2584 least_carrier ~> least_closed
  2585 greatest_carrier ~> greatest_closed
  2586 greatest_Lower_above ~> greatest_Lower_below
  2587 one_zero ~> carrier_one_zero
  2588 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  2589 
  2590 
  2591 *** HOL-Nominal ***
  2592 
  2593 * Nominal datatypes can now contain type-variables.
  2594 
  2595 * Commands 'nominal_inductive' and 'equivariance' work with local
  2596 theory targets.
  2597 
  2598 * Nominal primrec can now works with local theory targets and its
  2599 specification syntax now conforms to the general format as seen in
  2600 'inductive' etc.
  2601 
  2602 * Method "perm_simp" honours the standard simplifier attributes
  2603 (no_asm), (no_asm_use) etc.
  2604 
  2605 * The new predicate #* is defined like freshness, except that on the
  2606 left hand side can be a set or list of atoms.
  2607 
  2608 * Experimental command 'nominal_inductive2' derives strong induction
  2609 principles for inductive definitions.  In contrast to
  2610 'nominal_inductive', which can only deal with a fixed number of
  2611 binders, it can deal with arbitrary expressions standing for sets of
  2612 atoms to be avoided.  The only inductive definition we have at the
  2613 moment that needs this generalisation is the typing rule for Lets in
  2614 the algorithm W:
  2615 
  2616  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  2617  -----------------------------------------------------------------
  2618          Gamma |- Let x be t1 in t2 : T2
  2619 
  2620 In this rule one wants to avoid all the binders that are introduced by
  2621 "close Gamma T1".  We are looking for other examples where this
  2622 feature might be useful.  Please let us know.
  2623 
  2624 
  2625 *** HOLCF ***
  2626 
  2627 * Reimplemented the simplification procedure for proving continuity
  2628 subgoals.  The new simproc is extensible; users can declare additional
  2629 continuity introduction rules with the attribute [cont2cont].
  2630 
  2631 * The continuity simproc now uses a different introduction rule for
  2632 solving continuity subgoals on terms with lambda abstractions.  In
  2633 some rare cases the new simproc may fail to solve subgoals that the
  2634 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  2635 Potential INCOMPATIBILITY.
  2636 
  2637 * Command 'fixrec': specification syntax now conforms to the general
  2638 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  2639 examples.  INCOMPATIBILITY.
  2640 
  2641 
  2642 *** ZF ***
  2643 
  2644 * Proof of Zorn's Lemma for partial orders.
  2645 
  2646 
  2647 *** ML ***
  2648 
  2649 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  2650 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  2651 depends on multithreading, so timouts will not work before Poly/ML
  2652 5.2.1!
  2653 
  2654 * High-level support for concurrent ML programming, see
  2655 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  2656 particularly convenient to organize independent functional
  2657 computations.  The concept of "synchronized variables" provides a
  2658 higher-order interface for components with shared state, avoiding the
  2659 delicate details of mutexes and condition variables.  (Requires
  2660 Poly/ML 5.2.1 or later.)
  2661 
  2662 * ML bindings produced via Isar commands are stored within the Isar
  2663 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2664 become thread-safe and work with undo as expected (concerning
  2665 top-level bindings, not side-effects on global references).
  2666 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2667 compiler at runtime; really global bindings need to be given outside a
  2668 theory.  (Requires Poly/ML 5.2 or later.)
  2669 
  2670 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2671 context.  Top-level ML bindings are stored within the proof context in
  2672 a purely sequential fashion, disregarding the nested proof structure.
  2673 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2674 proof.  (Requires Poly/ML 5.2 or later.)
  2675 
  2676 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2677 and Method.setup, as well as Isar commands 'attribute_setup' and
  2678 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2679 existing code accordingly, or use plain 'setup' together with old
  2680 Method.add_method.
  2681 
  2682 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2683 to 'a -> thm, while results are always tagged with an authentic oracle
  2684 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2685 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2686 accordingly.  Note that extra performance may be gained by producing
  2687 the cterm carefully, avoiding slow Thm.cterm_of.
  2688 
  2689 * Simplified interface for defining document antiquotations via
  2690 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2691 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2692 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2693 examples.
  2694 
  2695 * More systematic treatment of long names, abstract name bindings, and
  2696 name space operations.  Basic operations on qualified names have been
  2697 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2698 Long_Name.append.  Old type bstring has been mostly replaced by
  2699 abstract type binding (see structure Binding), which supports precise
  2700 qualification by packages and local theory targets, as well as proper
  2701 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2702 bstring values into Binding.name, or better pass through abstract
  2703 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2704 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2705 
  2706 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2707 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2708 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2709 
  2710 * Disposed old type and term read functions (Sign.read_def_typ,
  2711 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2712 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2713 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2714 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2715 resort for legacy applications.
  2716 
  2717 * Disposed old declarations, tactics, tactic combinators that refer to
  2718 the simpset or claset of an implicit theory (such as Addsimps,
  2719 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2720 embedded ML text, or local_simpset_of with a proper context passed as
  2721 explicit runtime argument.
  2722 
  2723 * Rules and tactics that read instantiations (read_instantiate,
  2724 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2725 context, which is required for parsing and type-checking.  Moreover,
  2726 the variables are specified as plain indexnames, not string encodings
  2727 thereof.  INCOMPATIBILITY.
  2728 
  2729 * Generic Toplevel.add_hook interface allows to analyze the result of
  2730 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2731 for theorem dependency output of transactions resulting in a new
  2732 theory state.
  2733 
  2734 * ML antiquotations: block-structured compilation context indicated by
  2735 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2736 
  2737   @{binding name}                         - basic name binding
  2738   @{let ?pat = term}                      - term abbreviation (HO matching)
  2739   @{note name = fact}                     - fact abbreviation
  2740   @{thm fact}                             - singleton fact (with attributes)
  2741   @{thms fact}                            - general fact (with attributes)
  2742   @{lemma prop by method}                 - singleton goal
  2743   @{lemma prop by meth1 meth2}            - singleton goal
  2744   @{lemma prop1 ... propN by method}      - general goal
  2745   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2746   @{lemma (open) ...}                     - open derivation
  2747 
  2748 
  2749 *** System ***
  2750 
  2751 * The Isabelle "emacs" tool provides a specific interface to invoke
  2752 Proof General / Emacs, with more explicit failure if that is not
  2753 installed (the old isabelle-interface script silently falls back on
  2754 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2755 installation location of the Proof General distribution.
  2756 
  2757 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2758 the Isabelle process into a JVM/Scala application.  See
  2759 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2760 process wrapper has been discontinued.)
  2761 
  2762 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2763 
  2764 * Various status messages (with exact source position information) are
  2765 emitted, if proper markup print mode is enabled.  This allows
  2766 user-interface components to provide detailed feedback on internal
  2767 prover operations.
  2768 
  2769 
  2770 
  2771 New in Isabelle2008 (June 2008)
  2772 -------------------------------
  2773 
  2774 *** General ***
  2775 
  2776 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2777 and updated, with formally checked references as hyperlinks.
  2778 
  2779 * Theory loader: use_thy (and similar operations) no longer set the
  2780 implicit ML context, which was occasionally hard to predict and in
  2781 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2782 provides a proper context already.
  2783 
  2784 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2785 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2786 'use' within a theory file will do the job.
  2787 
  2788 * Name space merge now observes canonical order, i.e. the second space
  2789 is inserted into the first one, while existing entries in the first
  2790 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2791 swap theory imports.
  2792 
  2793 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2794 INCOMPATIBILITY in identifier syntax etc.
  2795 
  2796 * Outer syntax: string tokens no longer admit escaped white space,
  2797 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2798 white space without escapes.
  2799 
  2800 * Outer syntax: string tokens may contain arbitrary character codes
  2801 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2802 "foo_bar".
  2803 
  2804 
  2805 *** Pure ***
  2806 
  2807 * Context-dependent token translations.  Default setup reverts locally
  2808 fixed variables, and adds hilite markup for undeclared frees.
  2809 
  2810 * Unused theorems can be found using the new command 'unused_thms'.
  2811 There are three ways of invoking it:
  2812 
  2813 (1) unused_thms
  2814      Only finds unused theorems in the current theory.
  2815 
  2816 (2) unused_thms thy_1 ... thy_n -
  2817      Finds unused theorems in the current theory and all of its ancestors,
  2818      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2819 
  2820 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2821      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2822      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2823      their ancestors.
  2824 
  2825 In order to increase the readability of the list produced by
  2826 unused_thms, theorems that have been created by a particular instance
  2827 of a theory command such as 'inductive' or 'function' are considered
  2828 to belong to the same "group", meaning that if at least one theorem in
  2829 this group is used, the other theorems in the same group are no longer
  2830 reported as unused.  Moreover, if all theorems in the group are
  2831 unused, only one theorem in the group is displayed.
  2832 
  2833 Note that proof objects have to be switched on in order for
  2834 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2835 usually the case when using Proof General with the default settings).
  2836 
  2837 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2838 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2839 duplicate fact bindings, or even accidental fact duplications.  Note
  2840 that tools may maintain dynamically scoped facts systematically, using
  2841 PureThy.add_thms_dynamic.
  2842 
  2843 * Command 'hide' now allows to hide from "fact" name space as well.
  2844 
  2845 * Eliminated destructive theorem database, simpset, claset, and
  2846 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2847 update of theories within ML code.
  2848 
  2849 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2850 INCOMPATIBILITY, object-logics depending on former Pure require
  2851 additional setup PureThy.old_appl_syntax_setup; object-logics
  2852 depending on former CPure need to refer to Pure.
  2853 
  2854 * Commands 'use' and 'ML' are now purely functional, operating on
  2855 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2856 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2857 INCOMPATIBILITY.
  2858 
  2859 * Command 'setup': discontinued implicit version with ML reference.
  2860 
  2861 * Instantiation target allows for simultaneous specification of class
  2862 instance operations together with an instantiation proof.
  2863 Type-checking phase allows to refer to class operations uniformly.
  2864 See src/HOL/Complex/Complex.thy for an Isar example and
  2865 src/HOL/Library/Eval.thy for an ML example.
  2866 
  2867 * Indexing of literal facts: be more serious about including only
  2868 facts from the visible specification/proof context, but not the
  2869 background context (locale etc.).  Affects `prop` notation and method
  2870 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2871 situations.
  2872 
  2873 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2874 "(open)" option, which used to expose internal bound variables to the
  2875 proof text.
  2876 
  2877 * Isar statements: removed obsolete case "rule_context".
  2878 INCOMPATIBILITY, better use explicit fixes/assumes.
  2879 
  2880 * Locale proofs: default proof step now includes 'unfold_locales';
  2881 hence 'proof' without argument may be used to unfold locale
  2882 predicates.
  2883 
  2884 
  2885 *** Document preparation ***
  2886 
  2887 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2888 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2889 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2890 spot); renamed link color from "darkblue" to "linkcolor" (default
  2891 value unchanged, can be redefined via \definecolor); no longer sets
  2892 "a4paper" option (unnecessary or even intrusive).
  2893 
  2894 * Antiquotation @{lemma A method} proves proposition A by the given
  2895 method (either a method name or a method name plus (optional) method
  2896 arguments in parentheses) and prints A just like @{prop A}.
  2897 
  2898 
  2899 *** HOL ***
  2900 
  2901 * New primrec package.  Specification syntax conforms in style to
  2902 definition/function/....  No separate induction rule is provided.  The
  2903 "primrec" command distinguishes old-style and new-style specifications
  2904 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2905 When adjusting theories, beware: constants stemming from new-style
  2906 primrec specifications have authentic syntax.
  2907 
  2908 * Metis prover is now an order of magnitude faster, and also works
  2909 with multithreading.
  2910 
  2911 * Metis: the maximum number of clauses that can be produced from a
  2912 theorem is now given by the attribute max_clauses.  Theorems that
  2913 exceed this number are ignored, with a warning printed.
  2914 
  2915 * Sledgehammer no longer produces structured proofs by default. To
  2916 enable, declare [[sledgehammer_full = true]].  Attributes
  2917 reconstruction_modulus, reconstruction_sorts renamed
  2918 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2919 
  2920 * Method "induct_scheme" derives user-specified induction rules
  2921 from well-founded induction and completeness of patterns. This factors
  2922 out some operations that are done internally by the function package
  2923 and makes them available separately.  See
  2924 src/HOL/ex/Induction_Scheme.thy for examples.
  2925 
  2926 * More flexible generation of measure functions for termination
  2927 proofs: Measure functions can be declared by proving a rule of the
  2928 form "is_measure f" and giving it the [measure_function] attribute.
  2929 The "is_measure" predicate is logically meaningless (always true), and
  2930 just guides the heuristic.  To find suitable measure functions, the
  2931 termination prover sets up the goal "is_measure ?f" of the appropriate
  2932 type and generates all solutions by prolog-style backwards proof using
  2933 the declared rules.
  2934 
  2935 This setup also deals with rules like 
  2936 
  2937   "is_measure f ==> is_measure (list_size f)"
  2938 
  2939 which accommodates nested datatypes that recurse through lists.
  2940 Similar rules are predeclared for products and option types.
  2941 
  2942 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  2943 
  2944   INCOMPATIBILITIES:
  2945 
  2946   - Definitions of overloaded constants on sets have to be replaced by
  2947     definitions on => and bool.
  2948 
  2949   - Some definitions of overloaded operators on sets can now be proved
  2950     using the definitions of the operators on => and bool.  Therefore,
  2951     the following theorems have been renamed:
  2952 
  2953       subset_def   -> subset_eq
  2954       psubset_def  -> psubset_eq
  2955       set_diff_def -> set_diff_eq
  2956       Compl_def    -> Compl_eq
  2957       Sup_set_def  -> Sup_set_eq
  2958       Inf_set_def  -> Inf_set_eq
  2959       sup_set_def  -> sup_set_eq
  2960       inf_set_def  -> inf_set_eq
  2961 
  2962   - Due to the incompleteness of the HO unification algorithm, some
  2963     rules such as subst may require manual instantiation, if some of
  2964     the unknowns in the rule is a set.
  2965 
  2966   - Higher order unification and forward proofs:
  2967     The proof pattern
  2968 
  2969       have "P (S::'a set)" <...>
  2970       then have "EX S. P S" ..
  2971 
  2972     no longer works (due to the incompleteness of the HO unification
  2973     algorithm) and must be replaced by the pattern
  2974 
  2975       have "EX S. P S"
  2976       proof
  2977         show "P S" <...>
  2978       qed
  2979 
  2980   - Calculational reasoning with subst (or similar rules):
  2981     The proof pattern
  2982 
  2983       have "P (S::'a set)" <...>
  2984       also have "S = T" <...>
  2985       finally have "P T" .
  2986 
  2987     no longer works (for similar reasons as the previous example) and
  2988     must be replaced by something like
  2989 
  2990       have "P (S::'a set)" <...>
  2991       moreover have "S = T" <...>
  2992       ultimately have "P T" by simp
  2993 
  2994   - Tactics or packages written in ML code:
  2995     Code performing pattern matching on types via
  2996 
  2997       Type ("set", [T]) => ...
  2998 
  2999     must be rewritten. Moreover, functions like strip_type or
  3000     binder_types no longer return the right value when applied to a
  3001     type of the form
  3002 
  3003       T1 => ... => Tn => U => bool
  3004 
  3005     rather than
  3006 
  3007       T1 => ... => Tn => U set
  3008 
  3009 * Merged theories Wellfounded_Recursion, Accessible_Part and
  3010 Wellfounded_Relations to theory Wellfounded.
  3011 
  3012 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  3013 
  3014 * Class finite no longer treats UNIV as class parameter.  Use class
  3015 enum from theory Library/Enum instead to achieve a similar effect.
  3016 INCOMPATIBILITY.
  3017 
  3018 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  3019 and "Cons".  INCOMPATIBILITY.
  3020 
  3021 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  3022 Potential INCOMPATIBILITY.
  3023 
  3024 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  3025 injective_fst_snd removed, use split_eta and prod_eqI instead.
  3026 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  3027 
  3028 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  3029 the same name in theory Orderings:
  3030 
  3031   less_trans
  3032   less_linear
  3033   le_imp_less_or_eq
  3034   le_less_trans
  3035   less_le_trans
  3036   less_not_sym
  3037   less_asym
  3038 
  3039 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  3040 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  3041 and different variable names.
  3042 
  3043 * Library/Option_ord.thy: Canonical order on option type.
  3044 
  3045 * Library/RBT.thy: Red-black trees, an efficient implementation of
  3046 finite maps.
  3047 
  3048 * Library/Countable.thy: Type class for countable types.
  3049 
  3050 * Theory Int: The representation of numerals has changed.  The infix
  3051 operator BIT and the bit datatype with constructors B0 and B1 have
  3052 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  3053 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  3054 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  3055 accordingly.
  3056 
  3057 * Theory Nat: definition of <= and < on natural numbers no longer
  3058 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  3059 le_def and less_def have disappeared.  Consider lemmas not_less
  3060 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  3061 
  3062 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  3063 (whose purpose mainly is for various fold_set functionals) have been
  3064 abandoned in favor of the existing algebraic classes
  3065 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  3066 lower_semilattice (resp. upper_semilattice) and linorder.
  3067 INCOMPATIBILITY.
  3068 
  3069 * Theory Transitive_Closure: induct and cases rules now declare proper
  3070 case_names ("base" and "step").  INCOMPATIBILITY.
  3071 
  3072 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  3073 lattices.  The form set-specific version is available as
  3074 Inductive.lfp_ordinal_induct_set.
  3075 
  3076 * Renamed theorems "power.simps" to "power_int.simps".
  3077 INCOMPATIBILITY.
  3078 
  3079 * Class semiring_div provides basic abstract properties of semirings
  3080 with division and modulo operations.  Subsumes former class dvd_mod.
  3081 
  3082 * Merged theories IntDef, Numeral and IntArith into unified theory
  3083 Int.  INCOMPATIBILITY.
  3084 
  3085 * Theory Library/Code_Index: type "index" now represents natural
  3086 numbers rather than integers.  INCOMPATIBILITY.
  3087 
  3088 * New class "uminus" with operation "uminus" (split of from class
  3089 "minus" which now only has operation "minus", binary).
  3090 INCOMPATIBILITY.
  3091 
  3092 * Constants "card", "internal_split", "option_map" now with authentic
  3093 syntax.  INCOMPATIBILITY.
  3094 
  3095 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  3096 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  3097 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  3098 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  3099 Sup_set_def, le_def, less_def, option_map_def now with object
  3100 equality.  INCOMPATIBILITY.
  3101 
  3102 * Records. Removed K_record, and replaced it by pure lambda term
  3103 %x. c. The simplifier setup is now more robust against eta expansion.
  3104 INCOMPATIBILITY: in cases explicitly referring to K_record.
  3105 
  3106 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  3107 
  3108 * Library/ListVector: new theory of arithmetic vector operations.
  3109 
  3110 * Library/Order_Relation: new theory of various orderings as sets of
  3111 pairs.  Defines preorders, partial orders, linear orders and
  3112 well-orders on sets and on types.
  3113 
  3114 
  3115 *** ZF ***
  3116 
  3117 * Renamed some theories to allow to loading both ZF and HOL in the
  3118 same session:
  3119 
  3120   Datatype  -> Datatype_ZF
  3121   Inductive -> Inductive_ZF
  3122   Int       -> Int_ZF
  3123   IntDiv    -> IntDiv_ZF
  3124   Nat       -> Nat_ZF
  3125   List      -> List_ZF
  3126   Main      -> Main_ZF
  3127 
  3128 INCOMPATIBILITY: ZF theories that import individual theories below
  3129 Main might need to be adapted.  Regular theory Main is still
  3130 available, as trivial extension of Main_ZF.
  3131 
  3132 
  3133 *** ML ***
  3134 
  3135 * ML within Isar: antiquotation @{const name} or @{const
  3136 name(typargs)} produces statically-checked Const term.
  3137 
  3138 * Functor NamedThmsFun: data is available to the user as dynamic fact
  3139 (of the same name).  Removed obsolete print command.
  3140 
  3141 * Removed obsolete "use_legacy_bindings" function.
  3142 
  3143 * The ``print mode'' is now a thread-local value derived from a global
  3144 template (the former print_mode reference), thus access becomes
  3145 non-critical.  The global print_mode reference is for session
  3146 management only; user-code should use print_mode_value,
  3147 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  3148 
  3149 * Functions system/system_out provide a robust way to invoke external
  3150 shell commands, with propagation of interrupts (requires Poly/ML
  3151 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  3152 
  3153 
  3154 *** System ***
  3155 
  3156 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  3157 in accordance with Proof General 3.7, which prefers GNU emacs.
  3158 
  3159 * isatool tty runs Isabelle process with plain tty interaction;
  3160 optional line editor may be specified via ISABELLE_LINE_EDITOR
  3161 setting, the default settings attempt to locate "ledit" and "rlwrap".
  3162 
  3163 * isatool browser now works with Cygwin as well, using general
  3164 "javapath" function defined in Isabelle process environment.
  3165 
  3166 * YXML notation provides a simple and efficient alternative to
  3167 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  3168 isatool yxml as described in the Isabelle system manual.
  3169 
  3170 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  3171 provides general wrapper for managing an Isabelle process in a robust
  3172 fashion, with ``cooked'' output from stdin/stderr.
  3173 
  3174 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  3175 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  3176 
  3177 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  3178 way of changing the user's settings is via
  3179 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  3180 script.
  3181 
  3182 * Multithreading.max_threads := 0 refers to the number of actual CPU
  3183 cores of the underlying machine, which is a good starting point for
  3184 optimal performance tuning.  The corresponding usedir option -M allows
  3185 "max" as an alias for "0".  WARNING: does not work on certain versions
  3186 of Mac OS (with Poly/ML 5.1).
  3187 
  3188 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  3189 adverse effect of Isabelle flooding interactive front-ends (notably
  3190 ProofGeneral / XEmacs).
  3191 
  3192 
  3193 
  3194 New in Isabelle2007 (November 2007)
  3195 -----------------------------------
  3196 
  3197 *** General ***
  3198 
  3199 * More uniform information about legacy features, notably a
  3200 warning/error of "Legacy feature: ...", depending on the state of the
  3201 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  3202 legacy features will disappear eventually.
  3203 
  3204 * Theory syntax: the header format ``theory A = B + C:'' has been
  3205 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  3206 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  3207 
  3208 * Theory syntax: the old non-Isar theory file format has been
  3209 discontinued altogether.  Note that ML proof scripts may still be used
  3210 with Isar theories; migration is usually quite simple with the ML
  3211 function use_legacy_bindings.  INCOMPATIBILITY.
  3212 
  3213 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  3214 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  3215 quotes.
  3216 
  3217 * Theory loader: be more serious about observing the static theory
  3218 header specifications (including optional directories), but not the
  3219 accidental file locations of previously successful loads.  The strict
  3220 update policy of former update_thy is now already performed by
  3221 use_thy, so the former has been removed; use_thys updates several
  3222 theories simultaneously, just as 'imports' within a theory header
  3223 specification, but without merging the results.  Potential
  3224 INCOMPATIBILITY: may need to refine theory headers and commands
  3225 ROOT.ML which depend on load order.
  3226 
  3227 * Theory loader: optional support for content-based file
  3228 identification, instead of the traditional scheme of full physical
  3229 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  3230 (cf. the system manual).  The new scheme allows to work with
  3231 non-finished theories in persistent session images, such that source
  3232 files may be moved later on without requiring reloads.
  3233 
  3234 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3235 file (with the same base name as the theory) are considered a legacy
  3236 feature, which will disappear eventually. Even now, the theory loader
  3237 no longer maintains dependencies on such files.
  3238 
  3239 * Syntax: the scope for resolving ambiguities via type-inference is
  3240 now limited to individual terms, instead of whole simultaneous
  3241 specifications as before. This greatly reduces the complexity of the
  3242 syntax module and improves flexibility by separating parsing and
  3243 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  3244 'fixes' etc.) are required in rare situations.
  3245 
  3246 * Syntax: constants introduced by new-style packages ('definition',
  3247 'abbreviation' etc.) are passed through the syntax module in
  3248 ``authentic mode''. This means that associated mixfix annotations
  3249 really stick to such constants, independently of potential name space
  3250 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  3251 trees are represented slightly differently, may need to adapt syntax
  3252 translations accordingly. Use CONST marker in 'translations' and
  3253 @{const_syntax} antiquotation in 'parse_translation' etc.
  3254 
  3255 * Legacy goal package: reduced interface to the bare minimum required
  3256 to keep existing proof scripts running.  Most other user-level
  3257 functions are now part of the OldGoals structure, which is *not* open
  3258 by default (consider isatool expandshort before open OldGoals).
  3259 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  3260 these tend to cause confusion about the actual goal (!) context being
  3261 used here, which is not necessarily the same as the_context().
  3262 
  3263 * Command 'find_theorems': supports "*" wild-card in "name:"
  3264 criterion; "with_dups" option.  Certain ProofGeneral versions might
  3265 support a specific search form (see ProofGeneral/CHANGES).
  3266 
  3267 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  3268 by default, which means that "prems" (and also "fixed variables") are
  3269 suppressed from proof state output.  Note that the ProofGeneral
  3270 settings mechanism allows to change and save options persistently, but
  3271 older versions of Isabelle will fail to start up if a negative prems
  3272 limit is imposed.
  3273 
  3274 * Local theory targets may be specified by non-nested blocks of
  3275 ``context/locale/class ... begin'' followed by ``end''.  The body may
  3276 contain definitions, theorems etc., including any derived mechanism
  3277 that has been implemented on top of these primitives.  This concept
  3278 generalizes the existing ``theorem (in ...)'' towards more versatility
  3279 and scalability.
  3280 
  3281 * Proof General interface: proper undo of final 'end' command;
  3282 discontinued Isabelle/classic mode (ML proof scripts).
  3283 
  3284 
  3285 *** Document preparation ***
  3286 
  3287 * Added antiquotation @{theory name} which prints the given name,
  3288 after checking that it refers to a valid ancestor theory in the
  3289 current context.
  3290 
  3291 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  3292 check the given source text as ML type/structure, printing verbatim.
  3293 
  3294 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  3295 "c args == rhs" given in the current context.  (Any number of
  3296 arguments may be given on the LHS.)
  3297 
  3298 
  3299 *** Pure ***
  3300 
  3301 * The 'class' package offers a combination of axclass and locale to
  3302 achieve Haskell-like type classes in Isabelle.  Definitions and
  3303 theorems within a class context produce both relative results (with
  3304 implicit parameters according to the locale context), and polymorphic
  3305 constants with qualified polymorphism (according to the class
  3306 context).  Within the body context of a 'class' target, a separate
  3307 syntax layer ("user space type system") takes care of converting
  3308 between global polymorphic consts and internal locale representation.
  3309 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  3310 "isatool doc classes" provides a tutorial.
  3311 
  3312 * Generic code generator framework allows to generate executable
  3313 code for ML and Haskell (including Isabelle classes).  A short usage
  3314 sketch:
  3315 
  3316     internal compilation:
  3317         export_code <list of constants (term syntax)> in SML
  3318     writing SML code to a file:
  3319         export_code <list of constants (term syntax)> in SML <filename>
  3320     writing OCaml code to a file:
  3321         export_code <list of constants (term syntax)> in OCaml <filename>
  3322     writing Haskell code to a bunch of files:
  3323         export_code <list of constants (term syntax)> in Haskell <filename>
  3324 
  3325     evaluating closed propositions to True/False using code generation:
  3326         method ``eval''
  3327 
  3328 Reasonable default setup of framework in HOL.
  3329 
  3330 Theorem attributs for selecting and transforming function equations theorems:
  3331 
  3332     [code fun]:        select a theorem as function equation for a specific constant
  3333     [code fun del]:    deselect a theorem as function equation for a specific constant
  3334     [code inline]:     select an equation theorem for unfolding (inlining) in place
  3335     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  3336 
  3337 User-defined serializations (target in {SML, OCaml, Haskell}):
  3338 
  3339     code_const <and-list of constants (term syntax)>
  3340       {(target) <and-list of const target syntax>}+
  3341 
  3342     code_type <and-list of type constructors>
  3343       {(target) <and-list of type target syntax>}+
  3344 
  3345     code_instance <and-list of instances>
  3346       {(target)}+
  3347         where instance ::= <type constructor> :: <class>
  3348 
  3349     code_class <and_list of classes>
  3350       {(target) <and-list of class target syntax>}+
  3351         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  3352 
  3353 code_instance and code_class only are effective to target Haskell.
  3354 
  3355 For example usage see src/HOL/ex/Codegenerator.thy and
  3356 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  3357 generation from Isabelle/HOL theories is available via "isatool doc
  3358 codegen".
  3359 
  3360 * Code generator: consts in 'consts_code' Isar commands are now
  3361 referred to by usual term syntax (including optional type
  3362 annotations).
  3363 
  3364 * Command 'no_translations' removes translation rules from theory
  3365 syntax.
  3366 
  3367 * Overloaded definitions are now actually checked for acyclic
  3368 dependencies.  The overloading scheme is slightly more general than
  3369 that of Haskell98, although Isabelle does not demand an exact
  3370 correspondence to type class and instance declarations.
  3371 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  3372 exotic versions of overloading -- at the discretion of the user!
  3373 
  3374 Polymorphic constants are represented via type arguments, i.e. the
  3375 instantiation that matches an instance against the most general
  3376 declaration given in the signature.  For example, with the declaration
  3377 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  3378 as c(nat).  Overloading is essentially simultaneous structural
  3379 recursion over such type arguments.  Incomplete specification patterns
  3380 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  3381 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  3382 Command 'print_theory' outputs the normalized system of recursive
  3383 equations, see section "definitions".
  3384 
  3385 * Configuration options are maintained within the theory or proof
  3386 context (with name and type bool/int/string), providing a very simple
  3387 interface to a poor-man's version of general context data.  Tools may
  3388 declare options in ML (e.g. using Attrib.config_int) and then refer to
  3389 these values using Config.get etc.  Users may change options via an
  3390 associated attribute of the same name.  This form of context
  3391 declaration works particularly well with commands 'declare' or
  3392 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  3393 very easy to avoid global references, which would not observe Isar
  3394 toplevel undo/redo and fail to work with multithreading.
  3395 
  3396 Various global ML references of Pure and HOL have been turned into
  3397 configuration options:
  3398 
  3399   Unify.search_bound		unify_search_bound
  3400   Unify.trace_bound		unify_trace_bound
  3401   Unify.trace_simp		unify_trace_simp
  3402   Unify.trace_types		unify_trace_types
  3403   Simplifier.simp_depth_limit	simp_depth_limit
  3404   Blast.depth_limit		blast_depth_limit
  3405   DatatypeProp.dtK		datatype_distinctness_limit
  3406   fast_arith_neq_limit  	fast_arith_neq_limit
  3407   fast_arith_split_limit	fast_arith_split_limit
  3408 
  3409 * Named collections of theorems may be easily installed as context
  3410 data using the functor NamedThmsFun (see also
  3411 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  3412 attributes; there is also a toplevel print command.  This facility is
  3413 just a common case of general context data, which is the preferred way
  3414 for anything more complex than just a list of facts in canonical
  3415 order.
  3416 
  3417 * Isar: command 'declaration' augments a local theory by generic
  3418 declaration functions written in ML.  This enables arbitrary content
  3419 being added to the context, depending on a morphism that tells the
  3420 difference of the original declaration context wrt. the application
  3421 context encountered later on.
  3422 
  3423 * Isar: proper interfaces for simplification procedures.  Command
  3424 'simproc_setup' declares named simprocs (with match patterns, and body
  3425 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  3426 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  3427 
  3428 * Isar: an extra pair of brackets around attribute declarations
  3429 abbreviates a theorem reference involving an internal dummy fact,
  3430 which will be ignored later --- only the effect of the attribute on
  3431 the background context will persist.  This form of in-place
  3432 declarations is particularly useful with commands like 'declare' and
  3433 'using', for example ``have A using [[simproc a]] by simp''.
  3434 
  3435 * Isar: method "assumption" (and implicit closing of subproofs) now
  3436 takes simple non-atomic goal assumptions into account: after applying
  3437 an assumption as a rule the resulting subgoals are solved by atomic
  3438 assumption steps.  This is particularly useful to finish 'obtain'
  3439 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  3440 without referring to the original premise "!!x. P x ==> thesis" in the
  3441 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  3442 more permissive.
  3443 
  3444 * Isar: implicit use of prems from the Isar proof context is
  3445 considered a legacy feature.  Common applications like ``have A .''
  3446 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  3447 referencing facts explicitly here improves readability and
  3448 maintainability of proof texts.
  3449 
  3450 * Isar: improper proof element 'guess' is like 'obtain', but derives
  3451 the obtained context from the course of reasoning!  For example:
  3452 
  3453   assume "EX x y. A x & B y"   -- "any previous fact"
  3454   then guess x and y by clarify
  3455 
  3456 This technique is potentially adventurous, depending on the facts and
  3457 proof tools being involved here.
  3458 
  3459 * Isar: known facts from the proof context may be specified as literal
  3460 propositions, using ASCII back-quote syntax.  This works wherever
  3461 named facts used to be allowed so far, in proof commands, proof
  3462 methods, attributes etc.  Literal facts are retrieved from the context
  3463 according to unification of type and term parameters.  For example,
  3464 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  3465 theorems in the current context, then these are valid literal facts:
  3466 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  3467 
  3468 There is also a proof method "fact" which does the same composition
  3469 for explicit goal states, e.g. the following proof texts coincide with
  3470 certain special cases of literal facts:
  3471 
  3472   have "A" by fact                 ==  note `A`
  3473   have "A ==> B" by fact           ==  note `A ==> B`
  3474   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  3475   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  3476 
  3477 * Isar: ":" (colon) is no longer a symbolic identifier character in
  3478 outer syntax.  Thus symbolic identifiers may be used without
  3479 additional white space in declarations like this: ``assume *: A''.
  3480 
  3481 * Isar: 'print_facts' prints all local facts of the current context,
  3482 both named and unnamed ones.
  3483 
  3484 * Isar: 'def' now admits simultaneous definitions, e.g.:
  3485 
  3486   def x == "t" and y == "u"
  3487 
  3488 * Isar: added command 'unfolding', which is structurally similar to
  3489 'using', but affects both the goal state and facts by unfolding given
  3490 rewrite rules.  Thus many occurrences of the 'unfold' method or
  3491 'unfolded' attribute may be replaced by first-class proof text.
  3492 
  3493 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  3494 and command 'unfolding' now all support object-level equalities
  3495 (potentially conditional).  The underlying notion of rewrite rule is
  3496 analogous to the 'rule_format' attribute, but *not* that of the
  3497 Simplifier (which is usually more generous).
  3498 
  3499 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  3500 premises of a theorem by n. Useful in conjunction with drule.
  3501 
  3502 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  3503 method expression within a sandbox consisting of the first N
  3504 sub-goals, which need to exist.  For example, ``simp_all [3]''
  3505 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  3506 simplifies all new goals that emerge from applying rule foo to the
  3507 originally first one.
  3508 
  3509 * Isar: schematic goals are no longer restricted to higher-order
  3510 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  3511 expected.
  3512 
  3513 * Isar: the conclusion of a long theorem statement is now either
  3514 'shows' (a simultaneous conjunction, as before), or 'obtains'
  3515 (essentially a disjunction of cases with local parameters and
  3516 assumptions).  The latter allows to express general elimination rules
  3517 adequately; in this notation common elimination rules look like this:
  3518 
  3519   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  3520     assumes "EX x. P x"
  3521     obtains x where "P x"
  3522 
  3523   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  3524     assumes "A & B"
  3525     obtains A and B
  3526 
  3527   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  3528     assumes "A | B"
  3529     obtains
  3530       A
  3531     | B
  3532 
  3533 The subsequent classical rules even refer to the formal "thesis"
  3534 explicitly:
  3535 
  3536   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  3537     obtains "~ thesis"
  3538 
  3539   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  3540     obtains "thesis ==> something"
  3541 
  3542 The actual proof of an 'obtains' statement is analogous to that of the
  3543 Isar proof element 'obtain', only that there may be several cases.
  3544 Optional case names may be specified in parentheses; these will be
  3545 available both in the present proof and as annotations in the
  3546 resulting rule, for later use with the 'cases' method (cf. attribute
  3547 case_names).
  3548 
  3549 * Isar: the assumptions of a long theorem statement are available as
  3550 "assms" fact in the proof context.  This is more appropriate than the
  3551 (historical) "prems", which refers to all assumptions of the current
  3552 context, including those from the target locale, proof body etc.
  3553 
  3554 * Isar: 'print_statement' prints theorems from the current theory or
  3555 proof context in long statement form, according to the syntax of a
  3556 top-level lemma.
  3557 
  3558 * Isar: 'obtain' takes an optional case name for the local context
  3559 introduction rule (default "that").
  3560 
  3561 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  3562 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  3563 to occur.
  3564 
  3565 * Pure: syntax "CONST name" produces a fully internalized constant
  3566 according to the current context.  This is particularly useful for
  3567 syntax translations that should refer to internal constant
  3568 representations independently of name spaces.
  3569 
  3570 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  3571 instead of "FOO ". This allows multiple binder declarations to coexist
  3572 in the same context.  INCOMPATIBILITY.
  3573 
  3574 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  3575 primitive that also works in a locale context (both for constants and
  3576 fixed variables). Type declaration and internal syntactic representation
  3577 of given constants retrieved from the context. Likewise, the
  3578 'no_notation' command allows to remove given syntax annotations from the
  3579 current context.
  3580 
  3581 * Isar/locales: new derived specification elements 'axiomatization',
  3582 'definition', 'abbreviation', which support type-inference, admit
  3583 object-level specifications (equality, equivalence).  See also the
  3584 isar-ref manual.  Examples:
  3585 
  3586   axiomatization
  3587     eq  (infix "===" 50) where
  3588     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  3589 
  3590   definition "f x y = x + y + 1"
  3591   definition g where "g x = f x x"
  3592 
  3593   abbreviation
  3594     neq  (infix "=!=" 50) where
  3595     "x =!= y == ~ (x === y)"
  3596 
  3597 These specifications may be also used in a locale context.  Then the
  3598 constants being introduced depend on certain fixed parameters, and the
  3599 constant name is qualified by the locale base name.  An internal
  3600 abbreviation takes care for convenient input and output, making the
  3601 parameters implicit and using the original short name.  See also
  3602 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  3603 entities from a monomorphic theory.
  3604 
  3605 Presently, abbreviations are only available 'in' a target locale, but
  3606 not inherited by general import expressions.  Also note that
  3607 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  3608 'translations' in common applications.  The "no_abbrevs" print mode
  3609 prevents folding of abbreviations in term output.
  3610 
  3611 Concrete syntax is attached to specified constants in internal form,
  3612 independently of name spaces.  The parse tree representation is
  3613 slightly different -- use 'notation' instead of raw 'syntax', and
  3614 'translations' with explicit "CONST" markup to accommodate this.
  3615 
  3616 * Pure/Isar: unified syntax for new-style specification mechanisms
  3617 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  3618 full type inference and dummy patterns ("_").  For example:
  3619 
  3620   definition "K x _ = x"
  3621 
  3622   inductive conj for A B
  3623   where "A ==> B ==> conj A B"
  3624 
  3625 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  3626 the current context.  Print mode "no_abbrevs" prevents inversion of
  3627 abbreviations on output.
  3628 
  3629 * Isar/locales: improved parameter handling: use of locales "var" and
  3630 "struct" no longer necessary; - parameter renamings are no longer
  3631 required to be injective.  For example, this allows to define
  3632 endomorphisms as locale endom = homom mult mult h.
  3633 
  3634 * Isar/locales: changed the way locales with predicates are defined.
  3635 Instead of accumulating the specification, the imported expression is
  3636 now an interpretation.  INCOMPATIBILITY: different normal form of
  3637 locale expressions.  In particular, in interpretations of locales with
  3638 predicates, goals repesenting already interpreted fragments are not
  3639 removed automatically.  Use methods `intro_locales' and
  3640 `unfold_locales'; see below.
  3641 
  3642 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  3643 provide backward reasoning on locales predicates.  The methods are
  3644 aware of interpretations and discharge corresponding goals.
  3645 `intro_locales' is less aggressive then `unfold_locales' and does not
  3646 unfold predicates to assumptions.
  3647 
  3648 * Isar/locales: the order in which locale fragments are accumulated
  3649 has changed.  This enables to override declarations from fragments due
  3650 to interpretations -- for example, unwanted simp rules.
  3651 
  3652 * Isar/locales: interpretation in theories and proof contexts has been
  3653 extended.  One may now specify (and prove) equations, which are
  3654 unfolded in interpreted theorems.  This is useful for replacing
  3655 defined concepts (constants depending on locale parameters) by
  3656 concepts already existing in the target context.  Example:
  3657 
  3658   interpretation partial_order ["op <= :: [int, int] => bool"]
  3659     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3660 
  3661 Typically, the constant `partial_order.less' is created by a
  3662 definition specification element in the context of locale
  3663 partial_order.
  3664 
  3665 * Method "induct": improved internal context management to support
  3666 local fixes and defines on-the-fly. Thus explicit meta-level
  3667 connectives !!  and ==> are rarely required anymore in inductive goals
  3668 (using object-logic connectives for this purpose has been long
  3669 obsolete anyway). Common proof patterns are explained in
  3670 src/HOL/Induct/Common_Patterns.thy, see also
  3671 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3672 examples.
  3673 
  3674 * Method "induct": improved handling of simultaneous goals. Instead of
  3675 introducing object-level conjunction, the statement is now split into
  3676 several conclusions, while the corresponding symbolic cases are nested
  3677 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3678 see src/HOL/Induct/Common_Patterns.thy, for example.
  3679 
  3680 * Method "induct": mutual induction rules are now specified as a list
  3681 of rule sharing the same induction cases. HOL packages usually provide
  3682 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3683 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3684 mutual induction rules differently, i.e. like this:
  3685 
  3686   (induct rule: foo_bar.inducts)
  3687   (induct set: foo bar)
  3688   (induct pred: foo bar)
  3689   (induct type: foo bar)
  3690 
  3691 The ML function ProjectRule.projections turns old-style rules into the
  3692 new format.
  3693 
  3694 * Method "coinduct": dual of induction, see
  3695 src/HOL/Library/Coinductive_List.thy for various examples.
  3696 
  3697 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3698 considered a legacy feature.
  3699 
  3700 * Attribute "symmetric" produces result with standardized schematic
  3701 variables (index 0).  Potential INCOMPATIBILITY.
  3702 
  3703 * Simplifier: by default the simplifier trace only shows top level
  3704 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3705 default. Thus there is less danger of being flooded by the trace. The
  3706 trace indicates where parts have been suppressed.
  3707   
  3708 * Provers/classical: removed obsolete classical version of elim_format
  3709 attribute; classical elim/dest rules are now treated uniformly when
  3710 manipulating the claset.
  3711 
  3712 * Provers/classical: stricter checks to ensure that supplied intro,
  3713 dest and elim rules are well-formed; dest and elim rules must have at
  3714 least one premise.
  3715 
  3716 * Provers/classical: attributes dest/elim/intro take an optional
  3717 weight argument for the rule (just as the Pure versions).  Weights are
  3718 ignored by automated tools, but determine the search order of single
  3719 rule steps.
  3720 
  3721 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3722 where the body does not mention the bound variable.  Note that dummy
  3723 patterns implicitly depend on their context of bounds, which makes
  3724 "{_. _}" match any set comprehension as expected.  Potential
  3725 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3726 constant "_idtdummy" in the binding position.
  3727 
  3728 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3729 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3730 for example "A -> B" => "Pi A (%_. B)".
  3731 
  3732 * Pure: 'class_deps' command visualizes the subclass relation, using
  3733 the graph browser tool.
  3734 
  3735 * Pure: 'print_theory' now suppresses certain internal declarations by
  3736 default; use '!' option for full details.
  3737 
  3738 
  3739 *** HOL ***
  3740 
  3741 * Method "metis" proves goals by applying the Metis general-purpose
  3742 resolution prover (see also http://gilith.com/software/metis/).
  3743 Examples are in the directory MetisExamples.  WARNING: the
  3744 Isabelle/HOL-Metis integration does not yet work properly with
  3745 multi-threading.
  3746   
  3747 * Command 'sledgehammer' invokes external automatic theorem provers as
  3748 background processes.  It generates calls to the "metis" method if
  3749 successful. These can be pasted into the proof.  Users do not have to
  3750 wait for the automatic provers to return.  WARNING: does not really
  3751 work with multi-threading.
  3752 
  3753 * New "auto_quickcheck" feature tests outermost goal statements for
  3754 potential counter-examples.  Controlled by ML references
  3755 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3756 5000 milliseconds).  Fails silently if statements is outside of
  3757 executable fragment, or any other codgenerator problem occurs.
  3758 
  3759 * New constant "undefined" with axiom "undefined x = undefined".
  3760 
  3761 * Added class "HOL.eq", allowing for code generation with polymorphic
  3762 equality.
  3763 
  3764 * Some renaming of class constants due to canonical name prefixing in
  3765 the new 'class' package:
  3766 
  3767     HOL.abs ~> HOL.abs_class.abs
  3768     HOL.divide ~> HOL.divide_class.divide
  3769     0 ~> HOL.zero_class.zero
  3770     1 ~> HOL.one_class.one
  3771     op + ~> HOL.plus_class.plus
  3772     op - ~> HOL.minus_class.minus
  3773     uminus ~> HOL.minus_class.uminus
  3774     op * ~> HOL.times_class.times
  3775     op < ~> HOL.ord_class.less
  3776     op <= > HOL.ord_class.less_eq
  3777     Nat.power ~> Power.power_class.power
  3778     Nat.size ~> Nat.size_class.size
  3779     Numeral.number_of ~> Numeral.number_class.number_of
  3780     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3781     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3782     Orderings.min ~> Orderings.ord_class.min
  3783     Orderings.max ~> Orderings.ord_class.max
  3784     Divides.op div ~> Divides.div_class.div
  3785     Divides.op mod ~> Divides.div_class.mod
  3786     Divides.op dvd ~> Divides.div_class.dvd
  3787 
  3788 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3789 
  3790 a) User-defined constants using any of the names "plus", "minus",
  3791 "times", "less" or "less_eq". The standard syntax translations for
  3792 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3793 names.
  3794 
  3795 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3796 INCOMPATIBILITY: use more specific names.
  3797 
  3798 c) Permutative equations (e.g. "a + b = b + a")
  3799 Since the change of names also changes the order of terms, permutative
  3800 rewrite rules may get applied in a different order. Experience shows
  3801 that this is rarely the case (only two adaptions in the whole Isabelle
  3802 distribution).  INCOMPATIBILITY: rewrite proofs
  3803 
  3804 d) ML code directly refering to constant names
  3805 This in general only affects hand-written proof tactics, simprocs and
  3806 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3807 Consider using @{const_name} antiquotation.
  3808 
  3809 * New class "default" with associated constant "default".
  3810 
  3811 * Function "sgn" is now overloaded and available on int, real, complex
  3812 (and other numeric types), using class "sgn".  Two possible defs of
  3813 sgn are given as equational assumptions in the classes sgn_if and
  3814 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3815 INCOMPATIBILITY.
  3816 
  3817 * Locale "partial_order" now unified with class "order" (cf. theory
  3818 Orderings), added parameter "less".  INCOMPATIBILITY.
  3819 
  3820 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3821 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3822 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3823 
  3824 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3825 changed order of proof goals in instance proofs.
  3826 
  3827 * The transitivity reasoner for partial and linear orders is set up
  3828 for classes "order" and "linorder".  Instances of the reasoner are available
  3829 in all contexts importing or interpreting the corresponding locales.
  3830 Method "order" invokes the reasoner separately; the reasoner
  3831 is also integrated with the Simplifier as a solver.  Diagnostic
  3832 command 'print_orders' shows the available instances of the reasoner
  3833 in the current context.
  3834 
  3835 * Localized monotonicity predicate in theory "Orderings"; integrated
  3836 lemmas max_of_mono and min_of_mono with this predicate.
  3837 INCOMPATIBILITY.
  3838 
  3839 * Formulation of theorem "dense" changed slightly due to integration
  3840 with new class dense_linear_order.
  3841 
  3842 * Uniform lattice theory development in HOL.
  3843 
  3844     constants "meet" and "join" now named "inf" and "sup"
  3845     constant "Meet" now named "Inf"
  3846 
  3847     classes "meet_semilorder" and "join_semilorder" now named
  3848       "lower_semilattice" and "upper_semilattice"
  3849     class "lorder" now named "lattice"
  3850     class "comp_lat" now named "complete_lattice"
  3851 
  3852     Instantiation of lattice classes allows explicit definitions
  3853     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3854 
  3855   INCOMPATIBILITY.  Theorem renames:
  3856 
  3857     meet_left_le            ~> inf_le1
  3858     meet_right_le           ~> inf_le2
  3859     join_left_le            ~> sup_ge1
  3860     join_right_le           ~> sup_ge2
  3861     meet_join_le            ~> inf_sup_ord
  3862     le_meetI                ~> le_infI
  3863     join_leI                ~> le_supI
  3864     le_meet                 ~> le_inf_iff
  3865     le_join                 ~> ge_sup_conv
  3866     meet_idempotent         ~> inf_idem
  3867     join_idempotent         ~> sup_idem
  3868     meet_comm               ~> inf_commute
  3869     join_comm               ~> sup_commute
  3870     meet_leI1               ~> le_infI1
  3871     meet_leI2               ~> le_infI2
  3872     le_joinI1               ~> le_supI1
  3873     le_joinI2               ~> le_supI2
  3874     meet_assoc              ~> inf_assoc
  3875     join_assoc              ~> sup_assoc
  3876     meet_left_comm          ~> inf_left_commute
  3877     meet_left_idempotent    ~> inf_left_idem
  3878     join_left_comm          ~> sup_left_commute
  3879     join_left_idempotent    ~> sup_left_idem
  3880     meet_aci                ~> inf_aci
  3881     join_aci                ~> sup_aci
  3882     le_def_meet             ~> le_iff_inf
  3883     le_def_join             ~> le_iff_sup
  3884     join_absorp2            ~> sup_absorb2
  3885     join_absorp1            ~> sup_absorb1
  3886     meet_absorp1            ~> inf_absorb1
  3887     meet_absorp2            ~> inf_absorb2
  3888     meet_join_absorp        ~> inf_sup_absorb
  3889     join_meet_absorp        ~> sup_inf_absorb
  3890     distrib_join_le         ~> distrib_sup_le
  3891     distrib_meet_le         ~> distrib_inf_le
  3892 
  3893     add_meet_distrib_left   ~> add_inf_distrib_left
  3894     add_join_distrib_left   ~> add_sup_distrib_left
  3895     is_join_neg_meet        ~> is_join_neg_inf
  3896     is_meet_neg_join        ~> is_meet_neg_sup
  3897     add_meet_distrib_right  ~> add_inf_distrib_right
  3898     add_join_distrib_right  ~> add_sup_distrib_right
  3899     add_meet_join_distribs  ~> add_sup_inf_distribs
  3900     join_eq_neg_meet        ~> sup_eq_neg_inf
  3901     meet_eq_neg_join        ~> inf_eq_neg_sup
  3902     add_eq_meet_join        ~> add_eq_inf_sup
  3903     meet_0_imp_0            ~> inf_0_imp_0
  3904     join_0_imp_0            ~> sup_0_imp_0
  3905     meet_0_eq_0             ~> inf_0_eq_0
  3906     join_0_eq_0             ~> sup_0_eq_0
  3907     neg_meet_eq_join        ~> neg_inf_eq_sup
  3908     neg_join_eq_meet        ~> neg_sup_eq_inf
  3909     join_eq_if              ~> sup_eq_if
  3910 
  3911     mono_meet               ~> mono_inf
  3912     mono_join               ~> mono_sup
  3913     meet_bool_eq            ~> inf_bool_eq
  3914     join_bool_eq            ~> sup_bool_eq
  3915     meet_fun_eq             ~> inf_fun_eq
  3916     join_fun_eq             ~> sup_fun_eq
  3917     meet_set_eq             ~> inf_set_eq
  3918     join_set_eq             ~> sup_set_eq
  3919     meet1_iff               ~> inf1_iff
  3920     meet2_iff               ~> inf2_iff
  3921     meet1I                  ~> inf1I
  3922     meet2I                  ~> inf2I
  3923     meet1D1                 ~> inf1D1
  3924     meet2D1                 ~> inf2D1
  3925     meet1D2                 ~> inf1D2
  3926     meet2D2                 ~> inf2D2
  3927     meet1E                  ~> inf1E
  3928     meet2E                  ~> inf2E
  3929     join1_iff               ~> sup1_iff
  3930     join2_iff               ~> sup2_iff
  3931     join1I1                 ~> sup1I1
  3932     join2I1                 ~> sup2I1
  3933     join1I1                 ~> sup1I1
  3934     join2I2                 ~> sup1I2
  3935     join1CI                 ~> sup1CI
  3936     join2CI                 ~> sup2CI
  3937     join1E                  ~> sup1E
  3938     join2E                  ~> sup2E
  3939 
  3940     is_meet_Meet            ~> is_meet_Inf
  3941     Meet_bool_def           ~> Inf_bool_def
  3942     Meet_fun_def            ~> Inf_fun_def
  3943     Meet_greatest           ~> Inf_greatest
  3944     Meet_lower              ~> Inf_lower
  3945     Meet_set_def            ~> Inf_set_def
  3946 
  3947     Sup_def                 ~> Sup_Inf
  3948     Sup_bool_eq             ~> Sup_bool_def
  3949     Sup_fun_eq              ~> Sup_fun_def
  3950     Sup_set_eq              ~> Sup_set_def
  3951 
  3952     listsp_meetI            ~> listsp_infI
  3953     listsp_meet_eq          ~> listsp_inf_eq
  3954 
  3955     meet_min                ~> inf_min
  3956     join_max                ~> sup_max
  3957 
  3958 * Added syntactic class "size"; overloaded constant "size" now has
  3959 type "'a::size ==> bool"
  3960 
  3961 * Internal reorganisation of `size' of datatypes: size theorems
  3962 "foo.size" are no longer subsumed by "foo.simps" (but are still
  3963 simplification rules by default!); theorems "prod.size" now named
  3964 "*.size".
  3965 
  3966 * Class "div" now inherits from class "times" rather than "type".
  3967 INCOMPATIBILITY.
  3968 
  3969 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  3970 Linorder etc.  have disappeared; operations defined in terms of
  3971 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  3972 
  3973 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  3974 
  3975 * HOL-Word: New extensive library and type for generic, fixed size
  3976 machine words, with arithemtic, bit-wise, shifting and rotating
  3977 operations, reflection into int, nat, and bool lists, automation for
  3978 linear arithmetic (by automatic reflection into nat or int), including
  3979 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  3980 arithmetic type classes, supporting automatic simplification of
  3981 numerals on all operations.
  3982 
  3983 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  3984 
  3985 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  3986 
  3987 * Code generator library theories:
  3988   - Code_Integer represents HOL integers by big integer literals in target
  3989     languages.
  3990   - Code_Char represents HOL characters by character literals in target
  3991     languages.
  3992   - Code_Char_chr like Code_Char, but also offers treatment of character
  3993     codes; includes Code_Integer.
  3994   - Executable_Set allows to generate code for finite sets using lists.
  3995   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  3996     denominator).
  3997   - Executable_Real implements a subset of real numbers, namly those
  3998     representable by rational numbers.
  3999   - Efficient_Nat implements natural numbers by integers, which in general will
  4000     result in higher efficency; pattern matching with 0/Suc is eliminated;
  4001     includes Code_Integer.
  4002   - Code_Index provides an additional datatype index which is mapped to
  4003     target-language built-in integers.
  4004   - Code_Message provides an additional datatype message_string which is isomorphic to
  4005     strings; messages are mapped to target-language strings.
  4006 
  4007 * New package for inductive predicates
  4008 
  4009   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  4010 
  4011     inductive
  4012       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4013       for z_1 :: U_1 and ... and z_n :: U_m
  4014     where
  4015       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4016     | ...
  4017 
  4018   with full support for type-inference, rather than
  4019 
  4020     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4021 
  4022     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4023     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4024 
  4025     inductive "s z_1 ... z_m"
  4026     intros
  4027       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4028       ...
  4029 
  4030   For backward compatibility, there is a wrapper allowing inductive
  4031   sets to be defined with the new package via
  4032 
  4033     inductive_set
  4034       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4035       for z_1 :: U_1 and ... and z_n :: U_m
  4036     where
  4037       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4038     | ...
  4039 
  4040   or
  4041 
  4042     inductive_set
  4043       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4044       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4045       for z_1 :: U_1 and ... and z_n :: U_m
  4046     where
  4047       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4048     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4049     | ...
  4050 
  4051   if the additional syntax "p ..." is required.
  4052 
  4053   Numerous examples can be found in the subdirectories src/HOL/Auth,
  4054   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  4055 
  4056   INCOMPATIBILITIES:
  4057 
  4058   - Since declaration and definition of inductive sets or predicates
  4059     is no longer separated, abbreviations involving the newly
  4060     introduced sets or predicates must be specified together with the
  4061     introduction rules after the 'where' keyword (see above), rather
  4062     than before the actual inductive definition.
  4063 
  4064   - The variables in induction and elimination rules are now
  4065     quantified in the order of their occurrence in the introduction
  4066     rules, rather than in alphabetical order. Since this may break
  4067     some proofs, these proofs either have to be repaired, e.g. by
  4068     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  4069     statements of the form
  4070 
  4071       case (rule_i a_i_1 ... a_i_{k_i})
  4072 
  4073     or the old order of quantification has to be restored by explicitly adding
  4074     meta-level quantifiers in the introduction rules, i.e.
  4075 
  4076       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  4077 
  4078   - The format of the elimination rules is now
  4079 
  4080       p z_1 ... z_m x_1 ... x_n ==>
  4081         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4082         ==> ... ==> P
  4083 
  4084     for predicates and
  4085 
  4086       (x_1, ..., x_n) : s z_1 ... z_m ==>
  4087         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4088         ==> ... ==> P
  4089 
  4090     for sets rather than
  4091 
  4092       x : s z_1 ... z_m ==>
  4093         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  4094         ==> ... ==> P
  4095 
  4096     This may require terms in goals to be expanded to n-tuples
  4097     (e.g. using case_tac or simplification with the split_paired_all
  4098     rule) before the above elimination rule is applicable.
  4099 
  4100   - The elimination or case analysis rules for (mutually) inductive
  4101     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  4102     list of rules "p_1_..._p_k.elims" is no longer available.
  4103 
  4104 * New package "function"/"fun" for general recursive functions,
  4105 supporting mutual and nested recursion, definitions in local contexts,
  4106 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  4107 for small examples, and the separate tutorial on the function
  4108 package. The old recdef "package" is still available as before, but
  4109 users are encouraged to use the new package.
  4110 
  4111 * Method "lexicographic_order" automatically synthesizes termination
  4112 relations as lexicographic combinations of size measures. 
  4113 
  4114 * Case-expressions allow arbitrary constructor-patterns (including
  4115 "_") and take their order into account, like in functional
  4116 programming.  Internally, this is translated into nested
  4117 case-expressions; missing cases are added and mapped to the predefined
  4118 constant "undefined". In complicated cases printing may no longer show
  4119 the original input but the internal form. Lambda-abstractions allow
  4120 the same form of pattern matching: "% pat1 => e1 | ..." is an
  4121 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  4122 variable.
  4123 
  4124 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  4125 is an abbreviation for "of_nat :: nat => int". The simplification
  4126 rules for "of_nat" have been changed to work like "int" did
  4127 previously.  Potential INCOMPATIBILITY:
  4128   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  4129   - of_nat_diff and of_nat_mult are no longer default simp rules
  4130 
  4131 * Method "algebra" solves polynomial equations over (semi)rings using
  4132 Groebner bases. The (semi)ring structure is defined by locales and the
  4133 tool setup depends on that generic context. Installing the method for
  4134 a specific type involves instantiating the locale and possibly adding
  4135 declarations for computation on the coefficients.  The method is
  4136 already instantiated for natural numbers and for the axiomatic class
  4137 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  4138 CALCULEMUS 2007 for the general principles underlying this
  4139 architecture of context-aware proof-tools.
  4140 
  4141 * Method "ferrack" implements quantifier elimination over
  4142 special-purpose dense linear orders using locales (analogous to
  4143 "algebra"). The method is already installed for class
  4144 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  4145 rat, etc.
  4146 
  4147 * Former constant "List.op @" now named "List.append".  Use ML
  4148 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  4149 circumvent possible incompatibilities when working on ML level.
  4150 
  4151 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  4152 
  4153 * New function listsum :: 'a list => 'a for arbitrary monoids.
  4154 Special syntax: "SUM x <- xs. f x" (and latex variants)
  4155 
  4156 * New syntax for Haskell-like list comprehension (input only), eg.
  4157 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  4158 
  4159 * The special syntax for function "filter" has changed from [x :
  4160 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  4161 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  4162 
  4163 * [a..b] is now defined for arbitrary linear orders.  It used to be
  4164 defined on nat only, as an abbreviation for [a..<Suc b]
  4165 INCOMPATIBILITY.
  4166 
  4167 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  4168 
  4169 * New functions "sorted" and "sort" in src/HOL/List.thy.
  4170 
  4171 * New lemma collection field_simps (an extension of ring_simps) for
  4172 manipulating (in)equations involving division. Multiplies with all
  4173 denominators that can be proved to be non-zero (in equations) or
  4174 positive/negative (in inequations).
  4175 
  4176 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  4177 have been improved and renamed to ring_simps, group_simps and
  4178 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  4179 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  4180 
  4181 * Theory Library/Commutative_Ring: switched from recdef to function
  4182 package; constants add, mul, pow now curried.  Infix syntax for
  4183 algebraic operations.
  4184 
  4185 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  4186 INCOMPATIBILITY.
  4187 
  4188 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  4189 INCOMPATIBILITY.
  4190 
  4191 * HOL/records: generalised field-update to take a function on the
  4192 field rather than the new value: r(|A := x|) is translated to A_update
  4193 (K x) r The K-combinator that is internally used is called K_record.
  4194 INCOMPATIBILITY: Usage of the plain update functions has to be
  4195 adapted.
  4196  
  4197 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  4198 * x = 0, which are required for a semiring.  Richer structures do not
  4199 inherit from semiring_0 anymore, because this property is a theorem
  4200 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  4201 there is more to prove, but this is mostly trivial.
  4202 
  4203 * Class "recpower" is generalized to arbitrary monoids, not just
  4204 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  4205 commutativity or semiring properties additionally.
  4206 
  4207 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  4208 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  4209 better use 'abbreviation'.
  4210 
  4211 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  4212 
  4213 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  4214 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  4215 significant changes for setting up numeral syntax for types:
  4216   - New constants Numeral.pred and Numeral.succ instead
  4217       of former Numeral.bin_pred and Numeral.bin_succ.
  4218   - Use integer operations instead of bin_add, bin_mult and so on.
  4219   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  4220   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  4221 
  4222 See src/HOL/Integ/IntArith.thy for an example setup.
  4223 
  4224 * Command 'normal_form' computes the normal form of a term that may
  4225 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  4226 produces ``[b, c, a]'' (without proof).  This command is suitable for
  4227 heavy-duty computations because the functions are compiled to ML
  4228 first.  Correspondingly, a method "normalization" is provided.  See
  4229 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  4230 
  4231 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  4232 25 like -->); output depends on the "iff" print_mode, the default is
  4233 "A = B" (with priority 50).
  4234 
  4235 * Relations less (<) and less_eq (<=) are also available on type bool.
  4236 Modified syntax to disallow nesting without explicit parentheses,
  4237 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  4238 INCOMPATIBILITY.
  4239 
  4240 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  4241 
  4242 * Relation composition operator "op O" now has precedence 75 and binds
  4243 stronger than union and intersection. INCOMPATIBILITY.
  4244 
  4245 * The old set interval syntax "{m..n(}" (and relatives) has been
  4246 removed.  Use "{m..<n}" (and relatives) instead.
  4247 
  4248 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  4249 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  4250 ``declare [[simproc del: neq]]''.
  4251 
  4252 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  4253 True/False.
  4254 
  4255 * Theorem Cons_eq_map_conv no longer declared as "simp".
  4256 
  4257 * Theorem setsum_mult renamed to setsum_right_distrib.
  4258 
  4259 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  4260 ``rule'' method.
  4261 
  4262 * Reimplemented methods "sat" and "satx", with several improvements:
  4263 goals no longer need to be stated as "<prems> ==> False", equivalences
  4264 (i.e. "=" on type bool) are handled, variable names of the form
  4265 "lit_<n>" are no longer reserved, significant speedup.
  4266 
  4267 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  4268 zChaff is still supported as well.
  4269 
  4270 * 'inductive' and 'datatype': provide projections of mutual rules,
  4271 bundled as foo_bar.inducts;
  4272 
  4273 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  4274 Library.
  4275 
  4276 * Library: moved theory Accessible_Part to main HOL.
  4277 
  4278 * Library: added theory Coinductive_List of potentially infinite lists
  4279 as greatest fixed-point.
  4280 
  4281 * Library: added theory AssocList which implements (finite) maps as
  4282 association lists.
  4283 
  4284 * Method "evaluation" solves goals (i.e. a boolean expression)
  4285 efficiently by compiling it to ML.  The goal is "proved" (via an
  4286 oracle) if it evaluates to True.
  4287 
  4288 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  4289 also when invoked by the simplifier.  This results in the Simplifier
  4290 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  4291 Configuration option fast_arith_split_limit=0 recovers the old
  4292 behavior.
  4293 
  4294 * Support for hex (0x20) and binary (0b1001) numerals.
  4295 
  4296 * New method: reify eqs (t), where eqs are equations for an
  4297 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  4298 parameter, computes a term s::'b and a list xs::'a list and proves the
  4299 theorem I xs s = t. This is also known as reification or quoting. The
  4300 resulting theorem is applied to the subgoal to substitute t with I xs
  4301 s.  If t is omitted, the subgoal itself is reified.
  4302 
  4303 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  4304 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  4305 where f is supposed to be a computable function (in the sense of code
  4306 generattion). The method uses reify to compute s and xs as above then
  4307 applies corr_thm and uses normalization by evaluation to "prove" f s =
  4308 r and finally gets the theorem t = r, which is again applied to the
  4309 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  4310 
  4311 * Reflection: Automatic reification now handels binding, an example is
  4312 available in src/HOL/ex/ReflectionEx.thy
  4313 
  4314 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  4315 command 'statespace' that is similar to 'record', but introduces an
  4316 abstract specification based on the locale infrastructure instead of
  4317 HOL types.  This leads to extra flexibility in composing state spaces,
  4318 in particular multiple inheritance and renaming of components.
  4319 
  4320 
  4321 *** HOL-Complex ***
  4322 
  4323 * Hyperreal: Functions root and sqrt are now defined on negative real
  4324 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  4325 Nonnegativity side conditions have been removed from many lemmas, so
  4326 that more subgoals may now be solved by simplification; potential
  4327 INCOMPATIBILITY.
  4328 
  4329 * Real: new type classes formalize real normed vector spaces and
  4330 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  4331 and norm :: 'a => real.
  4332 
  4333 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  4334 reals into other types. The overloaded constant Reals :: 'a set is now
  4335 defined as range of_real; potential INCOMPATIBILITY.
  4336 
  4337 * Real: proper support for ML code generation, including 'quickcheck'.
  4338 Reals are implemented as arbitrary precision rationals.
  4339 
  4340 * Hyperreal: Several constants that previously worked only for the
  4341 reals have been generalized, so they now work over arbitrary vector
  4342 spaces. Type annotations may need to be added in some cases; potential
  4343 INCOMPATIBILITY.
  4344 
  4345   Infinitesimal  :: ('a::real_normed_vector) star set
  4346   HFinite        :: ('a::real_normed_vector) star set
  4347   HInfinite      :: ('a::real_normed_vector) star set
  4348   approx         :: ('a::real_normed_vector) star => 'a star => bool
  4349   monad          :: ('a::real_normed_vector) star => 'a star set
  4350   galaxy         :: ('a::real_normed_vector) star => 'a star set
  4351   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  4352   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  4353   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  4354   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  4355   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  4356   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  4357   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  4358   sgn            :: 'a::real_normed_vector => 'a
  4359   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  4360 
  4361 * Complex: Some complex-specific constants are now abbreviations for
  4362 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  4363 hnorm.  Other constants have been entirely removed in favor of the
  4364 polymorphic versions (INCOMPATIBILITY):
  4365 
  4366   approx        <-- capprox
  4367   HFinite       <-- CFinite
  4368   HInfinite     <-- CInfinite
  4369   Infinitesimal <-- CInfinitesimal
  4370   monad         <-- cmonad
  4371   galaxy        <-- cgalaxy
  4372   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  4373   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  4374   (ns)deriv     <-- (ns)cderiv
  4375 
  4376 
  4377 *** HOL-Algebra ***
  4378 
  4379 * Formalisation of ideals and the quotient construction over rings.
  4380 
  4381 * Order and lattice theory no longer based on records.
  4382 INCOMPATIBILITY.
  4383 
  4384 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  4385 greatest_closed.  INCOMPATIBILITY.
  4386 
  4387 * Method algebra is now set up via an attribute.  For examples see
  4388 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  4389 of algebraic structures.
  4390 
  4391 * Renamed theory CRing to Ring.
  4392 
  4393 
  4394 *** HOL-Nominal ***
  4395 
  4396 * Substantial, yet incomplete support for nominal datatypes (binding
  4397 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  4398 src/HOL/Nominal/Examples.  Prospective users should consult
  4399 http://isabelle.in.tum.de/nominal/
  4400 
  4401 
  4402 *** ML ***
  4403 
  4404 * ML basics: just one true type int, which coincides with IntInf.int
  4405 (even on SML/NJ).
  4406 
  4407 * ML within Isar: antiquotations allow to embed statically-checked
  4408 formal entities in the source, referring to the context available at
  4409 compile-time.  For example:
  4410 
  4411 ML {* @{sort "{zero,one}"} *}
  4412 ML {* @{typ "'a => 'b"} *}
  4413 ML {* @{term "%x. x"} *}
  4414 ML {* @{prop "x == y"} *}
  4415 ML {* @{ctyp "'a => 'b"} *}
  4416 ML {* @{cterm "%x. x"} *}
  4417 ML {* @{cprop "x == y"} *}
  4418 ML {* @{thm asm_rl} *}
  4419 ML {* @{thms asm_rl} *}
  4420 ML {* @{type_name c} *}
  4421 ML {* @{type_syntax c} *}
  4422 ML {* @{const_name c} *}
  4423 ML {* @{const_syntax c} *}
  4424 ML {* @{context} *}
  4425 ML {* @{theory} *}
  4426 ML {* @{theory Pure} *}
  4427 ML {* @{theory_ref} *}
  4428 ML {* @{theory_ref Pure} *}
  4429 ML {* @{simpset} *}
  4430 ML {* @{claset} *}
  4431 ML {* @{clasimpset} *}
  4432 
  4433 The same works for sources being ``used'' within an Isar context.
  4434 
  4435 * ML in Isar: improved error reporting; extra verbosity with
  4436 ML_Context.trace enabled.
  4437 
  4438 * Pure/General/table.ML: the join operations now works via exceptions
  4439 DUP/SAME instead of type option. This is simpler in simple cases, and
  4440 admits slightly more efficient complex applications.
  4441 
  4442 * Pure: 'advanced' translation functions (parse_translation etc.) now
  4443 use Context.generic instead of just theory.
  4444 
  4445 * Pure: datatype Context.generic joins theory/Proof.context and
  4446 provides some facilities for code that works in either kind of
  4447 context, notably GenericDataFun for uniform theory and proof data.
  4448 
  4449 * Pure: simplified internal attribute type, which is now always
  4450 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  4451 local (Proof.context) attributes have been discontinued, while
  4452 minimizing code duplication. Thm.rule_attribute and
  4453 Thm.declaration_attribute build canonical attributes; see also structure
  4454 Context for further operations on Context.generic, notably
  4455 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  4456 declarations and definitions.
  4457 
  4458 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  4459 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  4460 init only required for impure data. INCOMPATIBILITY: empty really need
  4461 to be empty (no dependencies on theory content!)
  4462 
  4463 * Pure/kernel: consts certification ignores sort constraints given in
  4464 signature declarations. (This information is not relevant to the
  4465 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  4466 potential INCOMPATIBILITY.
  4467 
  4468 * Pure: axiomatic type classes are now purely definitional, with
  4469 explicit proofs of class axioms and super class relations performed
  4470 internally. See Pure/axclass.ML for the main internal interfaces --
  4471 notably AxClass.define_class supercedes AxClass.add_axclass, and
  4472 AxClass.axiomatize_class/classrel/arity supersede
  4473 Sign.add_classes/classrel/arities.
  4474 
  4475 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  4476 global/local versions on theory vs. Proof.context have been
  4477 discontinued; Attrib.syntax and Method.syntax have been adapted
  4478 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  4479 attributes, methods, etc.
  4480 
  4481 * Pure: several functions of signature "... -> theory -> theory * ..."
  4482 have been reoriented to "... -> theory -> ... * theory" in order to
  4483 allow natural usage in combination with the ||>, ||>>, |-> and
  4484 fold_map combinators.
  4485 
  4486 * Pure: official theorem names (closed derivations) and additional
  4487 comments (tags) are now strictly separate.  Name hints -- which are
  4488 maintained as tags -- may be attached any time without affecting the
  4489 derivation.
  4490 
  4491 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  4492 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  4493 achieve the old behaviour.
  4494 
  4495 * Pure: the "Goal" constant is now called "prop", supporting a
  4496 slightly more general idea of ``protecting'' meta-level rule
  4497 statements.
  4498 
  4499 * Pure: Logic.(un)varify only works in a global context, which is now
  4500 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  4501 Logic.legacy_(un)varify as temporary workaround.
  4502 
  4503 * Pure: structure Name provides scalable operations for generating
  4504 internal variable names, notably Name.variants etc.  This replaces
  4505 some popular functions from term.ML:
  4506 
  4507   Term.variant		->  Name.variant
  4508   Term.variantlist	->  Name.variant_list
  4509   Term.invent_names	->  Name.invent_list
  4510 
  4511 Note that low-level renaming rarely occurs in new code -- operations
  4512 from structure Variable are used instead (see below).
  4513 
  4514 * Pure: structure Variable provides fundamental operations for proper
  4515 treatment of fixed/schematic variables in a context.  For example,
  4516 Variable.import introduces fixes for schematics of given facts and
  4517 Variable.export reverses the effect (up to renaming) -- this replaces
  4518 various freeze_thaw operations.
  4519 
  4520 * Pure: structure Goal provides simple interfaces for
  4521 init/conclude/finish and tactical prove operations (replacing former
  4522 Tactic.prove).  Goal.prove is the canonical way to prove results
  4523 within a given context; Goal.prove_global is a degraded version for
  4524 theory level goals, including a global Drule.standard.  Note that
  4525 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  4526 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  4527 in a locale context).
  4528 
  4529 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  4530 and type checking (Syntax.check_term etc.), with common combinations
  4531 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  4532 which are considered legacy and await removal.
  4533 
  4534 * Pure/Syntax: generic interfaces for type unchecking
  4535 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  4536 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  4537 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  4538 available for convenience, but refer to the very same operations using
  4539 a mere theory instead of a full context.
  4540 
  4541 * Isar: simplified treatment of user-level errors, using exception
  4542 ERROR of string uniformly.  Function error now merely raises ERROR,
  4543 without any side effect on output channels.  The Isar toplevel takes
  4544 care of proper display of ERROR exceptions.  ML code may use plain
  4545 handle/can/try; cat_error may be used to concatenate errors like this:
  4546 
  4547   ... handle ERROR msg => cat_error msg "..."
  4548 
  4549 Toplevel ML code (run directly or through the Isar toplevel) may be
  4550 embedded into the Isar toplevel with exception display/debug like
  4551 this:
  4552 
  4553   Isar.toplevel (fn () => ...)
  4554 
  4555 INCOMPATIBILITY, removed special transform_error facilities, removed
  4556 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  4557 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  4558 -- use plain ERROR instead.
  4559 
  4560 * Isar: theory setup now has type (theory -> theory), instead of a
  4561 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  4562 
  4563 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  4564 ProofContext.debug/verbose flags.
  4565 
  4566 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  4567 theory before entering a proof state.  Transactions now always see a
  4568 quasi-functional intermediate checkpoint, both in interactive and
  4569 batch mode.
  4570 
  4571 * Isar: simplified interfaces for outer syntax.  Renamed
  4572 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  4573 OuterSyntax.add_parsers -- this functionality is now included in
  4574 OuterSyntax.command etc.  INCOMPATIBILITY.
  4575 
  4576 * Simplifier: the simpset of a running simplification process now
  4577 contains a proof context (cf. Simplifier.the_context), which is the
  4578 very context that the initial simpset has been retrieved from (by
  4579 simpset_of/local_simpset_of).  Consequently, all plug-in components
  4580 (solver, looper etc.) may depend on arbitrary proof data.
  4581 
  4582 * Simplifier.inherit_context inherits the proof context (plus the
  4583 local bounds) of the current simplification process; any simproc
  4584 etc. that calls the Simplifier recursively should do this!  Removed
  4585 former Simplifier.inherit_bounds, which is already included here --
  4586 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  4587 specify an explicit context using Simplifier.context/theory_context.
  4588 
  4589 * Simplifier/Classical Reasoner: more abstract interfaces
  4590 change_simpset/claset for modifying the simpset/claset reference of a
  4591 theory; raw versions simpset/claset_ref etc. have been discontinued --
  4592 INCOMPATIBILITY.
  4593 
  4594 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  4595 "Trueprop" etc.
  4596 
  4597 
  4598 *** System ***
  4599 
  4600 * settings: the default heap location within ISABELLE_HOME_USER now
  4601 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  4602 Isabelle installations.
  4603 
  4604 * isabelle-process: option -S (secure mode) disables some critical
  4605 operations, notably runtime compilation and evaluation of ML source
  4606 code.
  4607 
  4608 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  4609 
  4610 * Support for parallel execution, using native multicore support of
  4611 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  4612 independent theories, according to the given theory header
  4613 specifications. The maximum number of worker threads is specified via
  4614 usedir option -M or the "max-threads" setting in Proof General. A
  4615 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  4616 to 6 on a 8-core machine.  User-code needs to observe certain
  4617 guidelines for thread-safe programming, see appendix A in the Isar
  4618 Implementation manual.
  4619 
  4620 
  4621 
  4622 New in Isabelle2005 (October 2005)
  4623 ----------------------------------
  4624 
  4625 *** General ***
  4626 
  4627 * Theory headers: the new header syntax for Isar theories is
  4628 
  4629   theory <name>
  4630   imports <theory1> ... <theoryN>
  4631   uses <file1> ... <fileM>
  4632   begin
  4633 
  4634 where the 'uses' part is optional.  The previous syntax
  4635 
  4636   theory <name> = <theory1> + ... + <theoryN>:
  4637 
  4638 will disappear in the next release.  Use isatool fixheaders to convert
  4639 existing theory files.  Note that there is no change in ancient
  4640 non-Isar theories now, but these will disappear soon.
  4641 
  4642 * Theory loader: parent theories can now also be referred to via
  4643 relative and absolute paths.
  4644 
  4645 * Command 'find_theorems' searches for a list of criteria instead of a
  4646 list of constants. Known criteria are: intro, elim, dest, name:string,
  4647 simp:term, and any term. Criteria can be preceded by '-' to select
  4648 theorems that do not match. Intro, elim, dest select theorems that
  4649 match the current goal, name:s selects theorems whose fully qualified
  4650 name contain s, and simp:term selects all simplification rules whose
  4651 lhs match term.  Any other term is interpreted as pattern and selects
  4652 all theorems matching the pattern. Available in ProofGeneral under
  4653 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  4654 
  4655   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  4656 
  4657 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  4658 matching the current goal as introduction rule and not having "HOL."
  4659 in their name (i.e. not being defined in theory HOL).
  4660 
  4661 * Command 'thms_containing' has been discontinued in favour of
  4662 'find_theorems'; INCOMPATIBILITY.
  4663 
  4664 * Communication with Proof General is now 8bit clean, which means that
  4665 Unicode text in UTF-8 encoding may be used within theory texts (both
  4666 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4667 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4668 
  4669   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4670   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4671 
  4672 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4673 Classical Reasoner.  Typical big applications run around 2 times
  4674 faster.
  4675 
  4676 
  4677 *** Document preparation ***
  4678 
  4679 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4680 of raw sources.  Only those symbols that do not require additional
  4681 LaTeX packages (depending on comments in isabellesym.sty) are
  4682 displayed properly, everything else is left verbatim.  isatool display
  4683 and isatool print are used as front ends (these are subject to the
  4684 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4685 
  4686 * Command tags control specific markup of certain regions of text,
  4687 notably folding and hiding.  Predefined tags include "theory" (for
  4688 theory begin and end), "proof" for proof commands, and "ML" for
  4689 commands involving ML code; the additional tags "visible" and
  4690 "invisible" are unused by default.  Users may give explicit tag
  4691 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4692 interpretation of tags is determined by the LaTeX job during document
  4693 preparation: see option -V of isatool usedir, or options -n and -t of
  4694 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4695 \isadroptag.
  4696 
  4697 Several document versions may be produced at the same time via isatool
  4698 usedir (the generated index.html will link all of them).  Typical
  4699 specifications include ''-V document=theory,proof,ML'' to present
  4700 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4701 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4702 these parts without any formal replacement text.  The Isabelle site
  4703 default settings produce ''document'' and ''outline'' versions as
  4704 specified above.
  4705 
  4706 * Several new antiquotations:
  4707 
  4708   @{term_type term} prints a term with its type annotated;
  4709 
  4710   @{typeof term} prints the type of a term;
  4711 
  4712   @{const const} is the same as @{term const}, but checks that the
  4713   argument is a known logical constant;
  4714 
  4715   @{term_style style term} and @{thm_style style thm} print a term or
  4716   theorem applying a "style" to it
  4717 
  4718   @{ML text}
  4719 
  4720 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4721 definitions, equations, inequations etc., 'concl' printing only the
  4722 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4723 to print the specified premise.  TermStyle.add_style provides an ML
  4724 interface for introducing further styles.  See also the "LaTeX Sugar"
  4725 document practical applications.  The ML antiquotation prints
  4726 type-checked ML expressions verbatim.
  4727 
  4728 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4729 and 'text' support optional locale specification '(in loc)', which
  4730 specifies the default context for interpreting antiquotations.  For
  4731 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4732 
  4733 * Option 'locale=NAME' of antiquotations specifies an alternative
  4734 context interpreting the subsequent argument.  For example: @{thm
  4735 [locale=lattice] inf_assoc}.
  4736 
  4737 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4738 a proof context.
  4739 
  4740 * Proper output of antiquotations for theory commands involving a
  4741 proof context (such as 'locale' or 'theorem (in loc) ...').
  4742 
  4743 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4744 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4745 
  4746 * isatool usedir: new option -C (default true) controls whether option
  4747 -D should include a copy of the original document directory; -C false
  4748 prevents unwanted effects such as copying of administrative CVS data.
  4749 
  4750 
  4751 *** Pure ***
  4752 
  4753 * Considerably improved version of 'constdefs' command.  Now performs
  4754 automatic type-inference of declared constants; additional support for
  4755 local structure declarations (cf. locales and HOL records), see also
  4756 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4757 sequential dependencies of definitions within a single 'constdefs'
  4758 section; moreover, the declared name needs to be an identifier.  If
  4759 all fails, consider to fall back on 'consts' and 'defs' separately.
  4760 
  4761 * Improved indexed syntax and implicit structures.  First of all,
  4762 indexed syntax provides a notational device for subscripted
  4763 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4764 expressions.  Secondly, in a local context with structure
  4765 declarations, number indexes \<^sub>n or the empty index (default
  4766 number 1) refer to a certain fixed variable implicitly; option
  4767 show_structs controls printing of implicit structures.  Typical
  4768 applications of these concepts involve record types and locales.
  4769 
  4770 * New command 'no_syntax' removes grammar declarations (and
  4771 translations) resulting from the given syntax specification, which is
  4772 interpreted in the same manner as for the 'syntax' command.
  4773 
  4774 * 'Advanced' translation functions (parse_translation etc.) may depend
  4775 on the signature of the theory context being presently used for
  4776 parsing/printing, see also isar-ref manual.
  4777 
  4778 * Improved 'oracle' command provides a type-safe interface to turn an
  4779 ML expression of type theory -> T -> term into a primitive rule of
  4780 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4781 is already included here); see also FOL/ex/IffExample.thy;
  4782 INCOMPATIBILITY.
  4783 
  4784 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4785 before); "cI" is no longer bound, use "c.intro" instead.
  4786 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4787 axclasses vs. locales.
  4788 
  4789 * Improved internal renaming of symbolic identifiers -- attach primes
  4790 instead of base 26 numbers.
  4791 
  4792 * New flag show_question_marks controls printing of leading question
  4793 marks in schematic variable names.
  4794 
  4795 * In schematic variable names, *any* symbol following \<^isub> or
  4796 \<^isup> is now treated as part of the base name.  For example, the
  4797 following works without printing of awkward ".0" indexes:
  4798 
  4799   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4800     by simp
  4801 
  4802 * Inner syntax includes (*(*nested*) comments*).
  4803 
  4804 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4805 annotations as "(00...)".
  4806 
  4807 * Clear separation of logical types and nonterminals, where the latter
  4808 may only occur in 'syntax' specifications or type abbreviations.
  4809 Before that distinction was only partially implemented via type class
  4810 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4811 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4812 exotic syntax specifications may require further adaption
  4813 (e.g. Cube/Cube.thy).
  4814 
  4815 * Removed obsolete type class "logic", use the top sort {} instead.
  4816 Note that non-logical types should be declared as 'nonterminals'
  4817 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4818 specifications.
  4819 
  4820 * Attributes 'induct' and 'cases': type or set names may now be
  4821 locally fixed variables as well.
  4822 
  4823 * Simplifier: can now control the depth to which conditional rewriting
  4824 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4825 Limit.
  4826 
  4827 * Simplifier: simplification procedures may now take the current
  4828 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4829 interface), which is very useful for calling the Simplifier
  4830 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4831 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4832 low-level mk_simproc no longer applies Logic.varify internally, to
  4833 allow for use in a context of fixed variables.
  4834 
  4835 * thin_tac now works even if the assumption being deleted contains !!
  4836 or ==>.  More generally, erule now works even if the major premise of
  4837 the elimination rule contains !! or ==>.
  4838 
  4839 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4840 
  4841 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4842 from Pure, which contains all common declarations already.  Both
  4843 theories are defined via plain Isabelle/Isar .thy files.
  4844 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4845 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4846 use isatool fixcpure to adapt your theory and ML sources.
  4847 
  4848 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4849 selections of theorems in named facts via index ranges.
  4850 
  4851 * 'print_theorems': in theory mode, really print the difference
  4852 wrt. the last state (works for interactive theory development only),
  4853 in proof mode print all local facts (cf. 'print_facts');
  4854 
  4855 * 'hide': option '(open)' hides only base names.
  4856 
  4857 * More efficient treatment of intermediate checkpoints in interactive
  4858 theory development.
  4859 
  4860 * Code generator is now invoked via code_module (incremental code
  4861 generation) and code_library (modular code generation, ML structures
  4862 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4863 must be quoted when used as identifiers.
  4864 
  4865 * New 'value' command for reading, evaluating and printing terms using
  4866 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4867 quoted when used as identifier.
  4868 
  4869 
  4870 *** Locales ***
  4871 
  4872 * New commands for the interpretation of locale expressions in
  4873 theories (1), locales (2) and proof contexts (3).  These generate
  4874 proof obligations from the expression specification.  After the
  4875 obligations have been discharged, theorems of the expression are added
  4876 to the theory, target locale or proof context.  The synopsis of the
  4877 commands is a follows:
  4878 
  4879   (1) interpretation expr inst
  4880   (2) interpretation target < expr
  4881   (3) interpret expr inst
  4882 
  4883 Interpretation in theories and proof contexts require a parameter
  4884 instantiation of terms from the current context.  This is applied to
  4885 specifications and theorems of the interpreted expression.
  4886 Interpretation in locales only permits parameter renaming through the
  4887 locale expression.  Interpretation is smart in that interpretations
  4888 that are active already do not occur in proof obligations, neither are
  4889 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4890 inspect active interpretations of a particular locale.  For details,
  4891 see the Isar Reference manual.  Examples can be found in
  4892 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4893 
  4894 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4895 'interpret' instead.
  4896 
  4897 * New context element 'constrains' for adding type constraints to
  4898 parameters.
  4899 
  4900 * Context expressions: renaming of parameters with syntax
  4901 redeclaration.
  4902 
  4903 * Locale declaration: 'includes' disallowed.
  4904 
  4905 * Proper static binding of attribute syntax -- i.e. types / terms /
  4906 facts mentioned as arguments are always those of the locale definition
  4907 context, independently of the context of later invocations.  Moreover,
  4908 locale operations (renaming and type / term instantiation) are applied
  4909 to attribute arguments as expected.
  4910 
  4911 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4912 actual attributes; rare situations may require Attrib.attribute to
  4913 embed those attributes into Attrib.src that lack concrete syntax.
  4914 Attribute implementations need to cooperate properly with the static
  4915 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4916 Attrib.XXX_thm etc. already do the right thing without further
  4917 intervention.  Only unusual applications -- such as "where" or "of"
  4918 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4919 on the context and the facts involved -- may have to assign parsed
  4920 values to argument tokens explicitly.
  4921 
  4922 * Changed parameter management in theorem generation for long goal
  4923 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4924 theorem statement in rare situations.
  4925 
  4926 * Locale inspection command 'print_locale' omits notes elements.  Use
  4927 'print_locale!' to have them included in the output.
  4928 
  4929 
  4930 *** Provers ***
  4931 
  4932 * Provers/hypsubst.ML: improved version of the subst method, for
  4933 single-step rewriting: it now works in bound variable contexts. New is
  4934 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  4935 rewrite a different subterm than the original subst method, which is
  4936 still available as 'simplesubst'.
  4937 
  4938 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  4939 and quasi orders.
  4940 
  4941 * Provers/trancl.ML: new transitivity reasoner for transitive and
  4942 reflexive-transitive closure of relations.
  4943 
  4944 * Provers/blast.ML: new reference depth_limit to make blast's depth
  4945 limit (previously hard-coded with a value of 20) user-definable.
  4946 
  4947 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  4948 is peformed already.  Object-logics merely need to finish their
  4949 initial simpset configuration as before.  INCOMPATIBILITY.
  4950 
  4951 
  4952 *** HOL ***
  4953 
  4954 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  4955 
  4956   syntax (epsilon)
  4957     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  4958 
  4959 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  4960 and x-symbol; use option '-m epsilon' to get it actually printed.
  4961 Moreover, the mathematically important symbolic identifier \<epsilon>
  4962 becomes available as variable, constant etc.  INCOMPATIBILITY,
  4963 
  4964 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  4965 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  4966 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  4967 support corresponding Isar calculations.
  4968 
  4969 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  4970 instead of ":".
  4971 
  4972 * theory SetInterval: changed the syntax for open intervals:
  4973 
  4974   Old       New
  4975   {..n(}    {..<n}
  4976   {)n..}    {n<..}
  4977   {m..n(}   {m..<n}
  4978   {)m..n}   {m<..n}
  4979   {)m..n(}  {m<..<n}
  4980 
  4981 The old syntax is still supported but will disappear in the next
  4982 release.  For conversion use the following Emacs search and replace
  4983 patterns (these are not perfect but work quite well):
  4984 
  4985   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  4986   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  4987 
  4988 * Theory Commutative_Ring (in Library): method comm_ring for proving
  4989 equalities in commutative rings; method 'algebra' provides a generic
  4990 interface.
  4991 
  4992 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  4993 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  4994 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  4995 be a tuple pattern.
  4996 
  4997 Some new syntax forms are available:
  4998 
  4999   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  5000   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  5001   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  5002   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  5003 
  5004 The latter form "\<Sum>x < k. e" used to be based on a separate
  5005 function "Summation", which has been discontinued.
  5006 
  5007 * theory Finite_Set: in structured induction proofs, the insert case
  5008 is now 'case (insert x F)' instead of the old counterintuitive 'case
  5009 (insert F x)'.
  5010 
  5011 * The 'refute' command has been extended to support a much larger
  5012 fragment of HOL, including axiomatic type classes, constdefs and
  5013 typedefs, inductive datatypes and recursion.
  5014 
  5015 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  5016 Requires zChaff with proof generation to be installed.  See
  5017 HOL/ex/SAT_Examples.thy for examples.
  5018 
  5019 * Datatype induction via method 'induct' now preserves the name of the
  5020 induction variable. For example, when proving P(xs::'a list) by
  5021 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  5022 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  5023 in unstructured proof scripts.
  5024 
  5025 * Reworked implementation of records.  Improved scalability for
  5026 records with many fields, avoiding performance problems for type
  5027 inference. Records are no longer composed of nested field types, but
  5028 of nested extension types. Therefore the record type only grows linear
  5029 in the number of extensions and not in the number of fields.  The
  5030 top-level (users) view on records is preserved.  Potential
  5031 INCOMPATIBILITY only in strange cases, where the theory depends on the
  5032 old record representation. The type generated for a record is called
  5033 <record_name>_ext_type.
  5034 
  5035 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  5036 proofs triggered by a record definition or a simproc (if
  5037 quick_and_dirty is enabled).  Definitions of large records can take
  5038 quite long.
  5039 
  5040 New simproc record_upd_simproc for simplification of multiple record
  5041 updates enabled by default.  Moreover, trivial updates are also
  5042 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  5043 occasionally, since simplification is more powerful by default.
  5044 
  5045 * typedef: proper support for polymorphic sets, which contain extra
  5046 type-variables in the term.
  5047 
  5048 * Simplifier: automatically reasons about transitivity chains
  5049 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  5050 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  5051 old proofs break occasionally as simplification may now solve more
  5052 goals than previously.
  5053 
  5054 * Simplifier: converts x <= y into x = y if assumption y <= x is
  5055 present.  Works for all partial orders (class "order"), in particular
  5056 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  5057 just like y <= x.
  5058 
  5059 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  5060 bound variable or a constant then the let is unfolded.  Otherwise
  5061 first a is simplified to b, and then f b is simplified to g. If
  5062 possible we abstract b from g arriving at "let x = b in h x",
  5063 otherwise we unfold the let and arrive at g.  The simproc can be
  5064 enabled/disabled by the reference use_let_simproc.  Potential
  5065 INCOMPATIBILITY since simplification is more powerful by default.
  5066 
  5067 * Classical reasoning: the meson method now accepts theorems as arguments.
  5068 
  5069 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  5070 jobs to provide advice on the provability of subgoals.
  5071 
  5072 * Theory OrderedGroup and Ring_and_Field: various additions and
  5073 improvements to faciliate calculations involving equalities and
  5074 inequalities.
  5075 
  5076 The following theorems have been eliminated or modified
  5077 (INCOMPATIBILITY):
  5078 
  5079   abs_eq             now named abs_of_nonneg
  5080   abs_of_ge_0        now named abs_of_nonneg
  5081   abs_minus_eq       now named abs_of_nonpos
  5082   imp_abs_id         now named abs_of_nonneg
  5083   imp_abs_neg_id     now named abs_of_nonpos
  5084   mult_pos           now named mult_pos_pos
  5085   mult_pos_le        now named mult_nonneg_nonneg
  5086   mult_pos_neg_le    now named mult_nonneg_nonpos
  5087   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  5088   mult_neg           now named mult_neg_neg
  5089   mult_neg_le        now named mult_nonpos_nonpos
  5090 
  5091 * The following lemmas in Ring_and_Field have been added to the simplifier:
  5092      
  5093      zero_le_square
  5094      not_square_less_zero 
  5095 
  5096   The following lemmas have been deleted from Real/RealPow:
  5097   
  5098      realpow_zero_zero
  5099      realpow_two
  5100      realpow_less
  5101      zero_le_power
  5102      realpow_two_le
  5103      abs_realpow_two
  5104      realpow_two_abs     
  5105 
  5106 * Theory Parity: added rules for simplifying exponents.
  5107 
  5108 * Theory List:
  5109 
  5110 The following theorems have been eliminated or modified
  5111 (INCOMPATIBILITY):
  5112 
  5113   list_all_Nil       now named list_all.simps(1)
  5114   list_all_Cons      now named list_all.simps(2)
  5115   list_all_conv      now named list_all_iff
  5116   set_mem_eq         now named mem_iff
  5117 
  5118 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  5119 asymptotic "big O" calculations.  See the notes in BigO.thy.
  5120 
  5121 
  5122 *** HOL-Complex ***
  5123 
  5124 * Theory RealDef: better support for embedding natural numbers and
  5125 integers in the reals.
  5126 
  5127 The following theorems have been eliminated or modified
  5128 (INCOMPATIBILITY):
  5129 
  5130   exp_ge_add_one_self  now requires no hypotheses
  5131   real_of_int_add      reversed direction of equality (use [symmetric])
  5132   real_of_int_minus    reversed direction of equality (use [symmetric])
  5133   real_of_int_diff     reversed direction of equality (use [symmetric])
  5134   real_of_int_mult     reversed direction of equality (use [symmetric])
  5135 
  5136 * Theory RComplete: expanded support for floor and ceiling functions.
  5137 
  5138 * Theory Ln is new, with properties of the natural logarithm
  5139 
  5140 * Hyperreal: There is a new type constructor "star" for making
  5141 nonstandard types.  The old type names are now type synonyms:
  5142 
  5143   hypreal = real star
  5144   hypnat = nat star
  5145   hcomplex = complex star
  5146 
  5147 * Hyperreal: Many groups of similarly-defined constants have been
  5148 replaced by polymorphic versions (INCOMPATIBILITY):
  5149 
  5150   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  5151 
  5152   starset      <-- starsetNat, starsetC
  5153   *s*          <-- *sNat*, *sc*
  5154   starset_n    <-- starsetNat_n, starsetC_n
  5155   *sn*         <-- *sNatn*, *scn*
  5156   InternalSets <-- InternalNatSets, InternalCSets
  5157 
  5158   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  5159   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  5160   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  5161   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  5162   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  5163 
  5164 * Hyperreal: Many type-specific theorems have been removed in favor of
  5165 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  5166 
  5167   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  5168   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  5169   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  5170   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  5171   right_minus <-- hypreal_add_minus
  5172   left_minus <-- {hypreal,hcomplex}_add_minus_left
  5173   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  5174   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  5175   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  5176   mult_1_right <-- hcomplex_mult_one_right
  5177   mult_zero_left <-- hcomplex_mult_zero_left
  5178   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  5179   right_distrib <-- hypnat_add_mult_distrib2
  5180   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  5181   right_inverse <-- hypreal_mult_inverse
  5182   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  5183   order_refl <-- {hypreal,hypnat}_le_refl
  5184   order_trans <-- {hypreal,hypnat}_le_trans
  5185   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  5186   order_less_le <-- {hypreal,hypnat}_less_le
  5187   linorder_linear <-- {hypreal,hypnat}_le_linear
  5188   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  5189   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  5190   add_nonneg_nonneg <-- hypreal_le_add_order
  5191 
  5192 * Hyperreal: Separate theorems having to do with type-specific
  5193 versions of constants have been merged into theorems that apply to the
  5194 new polymorphic constants (INCOMPATIBILITY):
  5195 
  5196   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  5197   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  5198   STAR_Un <-- {STAR,NatStar,STARC}_Un
  5199   STAR_Int <-- {STAR,NatStar,STARC}_Int
  5200   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  5201   STAR_subset <-- {STAR,NatStar,STARC}_subset
  5202   STAR_mem <-- {STAR,NatStar,STARC}_mem
  5203   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  5204   STAR_diff <-- {STAR,STARC}_diff
  5205   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  5206     STARC_hcomplex_of_complex}_image_subset
  5207   starset_n_Un <-- starset{Nat,C}_n_Un
  5208   starset_n_Int <-- starset{Nat,C}_n_Int
  5209   starset_n_Compl <-- starset{Nat,C}_n_Compl
  5210   starset_n_diff <-- starset{Nat,C}_n_diff
  5211   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  5212   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  5213   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  5214   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  5215   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  5216   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  5217   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  5218   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  5219   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  5220   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  5221   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  5222   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  5223   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  5224   starfun_diff <-- starfun{C,RC,CR}_diff
  5225   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  5226   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  5227   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  5228   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  5229   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  5230   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  5231   starfun_Id <-- starfunC_Id
  5232   starfun_approx <-- starfun{Nat,CR}_approx
  5233   starfun_capprox <-- starfun{C,RC}_capprox
  5234   starfun_abs <-- starfunNat_rabs
  5235   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  5236   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  5237   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  5238   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  5239   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  5240   starfun_add_approx <-- starfunCR_add_approx
  5241   starfun_inverse_inverse <-- starfunC_inverse_inverse
  5242   starfun_divide <-- starfun{C,CR,RC}_divide
  5243   starfun_n <-- starfun{Nat,C}_n
  5244   starfun_n_mult <-- starfun{Nat,C}_n_mult
  5245   starfun_n_add <-- starfun{Nat,C}_n_add
  5246   starfun_n_add_minus <-- starfunNat_n_add_minus
  5247   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  5248   starfun_n_minus <-- starfun{Nat,C}_n_minus
  5249   starfun_n_eq <-- starfun{Nat,C}_n_eq
  5250 
  5251   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  5252   star_n_minus <-- {hypreal,hcomplex}_minus
  5253   star_n_diff <-- {hypreal,hcomplex}_diff
  5254   star_n_mult <-- {hypreal,hcomplex}_mult
  5255   star_n_inverse <-- {hypreal,hcomplex}_inverse
  5256   star_n_le <-- {hypreal,hypnat}_le
  5257   star_n_less <-- {hypreal,hypnat}_less
  5258   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  5259   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  5260   star_n_abs <-- hypreal_hrabs
  5261   star_n_divide <-- hcomplex_divide
  5262 
  5263   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  5264   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  5265   star_of_diff <-- hypreal_of_real_diff
  5266   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  5267   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  5268   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  5269   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  5270   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  5271   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  5272   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  5273   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  5274   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  5275   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  5276   star_of_number_of <-- {hypreal,hcomplex}_number_of
  5277   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  5278   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  5279   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  5280   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  5281   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  5282   star_of_power <-- hypreal_of_real_power
  5283   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  5284 
  5285 * Hyperreal: new method "transfer" that implements the transfer
  5286 principle of nonstandard analysis. With a subgoal that mentions
  5287 nonstandard types like "'a star", the command "apply transfer"
  5288 replaces it with an equivalent one that mentions only standard types.
  5289 To be successful, all free variables must have standard types; non-
  5290 standard variables must have explicit universal quantifiers.
  5291 
  5292 * Hyperreal: A theory of Taylor series.
  5293 
  5294 
  5295 *** HOLCF ***
  5296 
  5297 * Discontinued special version of 'constdefs' (which used to support
  5298 continuous functions) in favor of the general Pure one with full
  5299 type-inference.
  5300 
  5301 * New simplification procedure for solving continuity conditions; it
  5302 is much faster on terms with many nested lambda abstractions (cubic
  5303 instead of exponential time).
  5304 
  5305 * New syntax for domain package: selector names are now optional.
  5306 Parentheses should be omitted unless argument is lazy, for example:
  5307 
  5308   domain 'a stream = cons "'a" (lazy "'a stream")
  5309 
  5310 * New command 'fixrec' for defining recursive functions with pattern
  5311 matching; defining multiple functions with mutual recursion is also
  5312 supported.  Patterns may include the constants cpair, spair, up, sinl,
  5313 sinr, or any data constructor defined by the domain package. The given
  5314 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  5315 syntax and examples.
  5316 
  5317 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  5318 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  5319 but the proof obligation additionally includes an admissibility
  5320 requirement. The packages generate instances of class cpo or pcpo,
  5321 with continuity and strictness theorems for Rep and Abs.
  5322 
  5323 * HOLCF: Many theorems have been renamed according to a more standard naming
  5324 scheme (INCOMPATIBILITY):
  5325 
  5326   foo_inject:  "foo$x = foo$y ==> x = y"
  5327   foo_eq:      "(foo$x = foo$y) = (x = y)"
  5328   foo_less:    "(foo$x << foo$y) = (x << y)"
  5329   foo_strict:  "foo$UU = UU"
  5330   foo_defined: "... ==> foo$x ~= UU"
  5331   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  5332 
  5333 
  5334 *** ZF ***
  5335 
  5336 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  5337 including the First Isomorphism Theorem (on quotienting by the kernel
  5338 of a homomorphism).
  5339 
  5340 * ZF/Simplifier: install second copy of type solver that actually
  5341 makes use of TC rules declared to Isar proof contexts (or locales);
  5342 the old version is still required for ML proof scripts.
  5343 
  5344 
  5345 *** Cube ***
  5346 
  5347 * Converted to Isar theory format; use locales instead of axiomatic
  5348 theories.
  5349 
  5350 
  5351 *** ML ***
  5352 
  5353 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  5354 for ||>, ||>>, |>>,
  5355 
  5356 * Pure/library.ML no longer defines its own option datatype, but uses
  5357 that of the SML basis, which has constructors NONE and SOME instead of
  5358 None and Some, as well as exception Option.Option instead of OPTION.
  5359 The functions the, if_none, is_some, is_none have been adapted
  5360 accordingly, while Option.map replaces apsome.
  5361 
  5362 * Pure/library.ML: the exception LIST has been given up in favour of
  5363 the standard exceptions Empty and Subscript, as well as
  5364 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  5365 superceded by the standard hd and tl functions etc.
  5366 
  5367 A number of basic list functions are no longer exported to the ML
  5368 toplevel, as they are variants of predefined functions.  The following
  5369 suggests how one can translate existing code:
  5370 
  5371     rev_append xs ys = List.revAppend (xs, ys)
  5372     nth_elem (i, xs) = List.nth (xs, i)
  5373     last_elem xs = List.last xs
  5374     flat xss = List.concat xss
  5375     seq fs = List.app fs
  5376     partition P xs = List.partition P xs
  5377     mapfilter f xs = List.mapPartial f xs
  5378 
  5379 * Pure/library.ML: several combinators for linear functional
  5380 transformations, notably reverse application and composition:
  5381 
  5382   x |> f                f #> g
  5383   (x, y) |-> f          f #-> g
  5384 
  5385 * Pure/library.ML: introduced/changed precedence of infix operators:
  5386 
  5387   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  5388   infix 2 ?;
  5389   infix 3 o oo ooo oooo;
  5390   infix 4 ~~ upto downto;
  5391 
  5392 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  5393 infix operators.
  5394 
  5395 * Pure/library.ML: natural list combinators fold, fold_rev, and
  5396 fold_map support linear functional transformations and nesting.  For
  5397 example:
  5398 
  5399   fold f [x1, ..., xN] y =
  5400     y |> f x1 |> ... |> f xN
  5401 
  5402   (fold o fold) f [xs1, ..., xsN] y =
  5403     y |> fold f xs1 |> ... |> fold f xsN
  5404 
  5405   fold f [x1, ..., xN] =
  5406     f x1 #> ... #> f xN
  5407 
  5408   (fold o fold) f [xs1, ..., xsN] =
  5409     fold f xs1 #> ... #> fold f xsN
  5410 
  5411 * Pure/library.ML: the following selectors on type 'a option are
  5412 available:
  5413 
  5414   the:               'a option -> 'a  (*partial*)
  5415   these:             'a option -> 'a  where 'a = 'b list
  5416   the_default: 'a -> 'a option -> 'a
  5417   the_list:          'a option -> 'a list
  5418 
  5419 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5420 basic operations for association lists, following natural argument
  5421 order; moreover the explicit equality predicate passed here avoids
  5422 potentially expensive polymorphic runtime equality checks.
  5423 The old functions may be expressed as follows:
  5424 
  5425   assoc = uncurry (AList.lookup (op =))
  5426   assocs = these oo AList.lookup (op =)
  5427   overwrite = uncurry (AList.update (op =)) o swap
  5428 
  5429 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5430 
  5431   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  5432   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  5433 
  5434 replacing make_keylist and keyfilter (occassionally used)
  5435 Naive rewrites:
  5436 
  5437   make_keylist = AList.make
  5438   keyfilter = AList.find (op =)
  5439 
  5440 * eq_fst and eq_snd now take explicit equality parameter, thus
  5441   avoiding eqtypes. Naive rewrites:
  5442 
  5443     eq_fst = eq_fst (op =)
  5444     eq_snd = eq_snd (op =)
  5445 
  5446 * Removed deprecated apl and apr (rarely used).
  5447   Naive rewrites:
  5448 
  5449     apl (n, op) =>>= curry op n
  5450     apr (op, m) =>>= fn n => op (n, m)
  5451 
  5452 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  5453 provides a reasonably efficient light-weight implementation of sets as
  5454 lists.
  5455 
  5456 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  5457 few new operations; existing lookup and update are now curried to
  5458 follow natural argument order (for use with fold etc.);
  5459 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  5460 
  5461 * Pure/General: output via the Isabelle channels of
  5462 writeln/warning/error etc. is now passed through Output.output, with a
  5463 hook for arbitrary transformations depending on the print_mode
  5464 (cf. Output.add_mode -- the first active mode that provides a output
  5465 function wins).  Already formatted output may be embedded into further
  5466 text via Output.raw; the result of Pretty.string_of/str_of and derived
  5467 functions (string_of_term/cterm/thm etc.) is already marked raw to
  5468 accommodate easy composition of diagnostic messages etc.  Programmers
  5469 rarely need to care about Output.output or Output.raw at all, with
  5470 some notable exceptions: Output.output is required when bypassing the
  5471 standard channels (writeln etc.), or in token translations to produce
  5472 properly formatted results; Output.raw is required when capturing
  5473 already output material that will eventually be presented to the user
  5474 a second time.  For the default print mode, both Output.output and
  5475 Output.raw have no effect.
  5476 
  5477 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  5478 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  5479 cumulative results are displayed at the end of a batch session.
  5480 
  5481 * Pure/General: File.sysify_path and File.quote_sysify path have been
  5482 replaced by File.platform_path and File.shell_path (with appropriate
  5483 hooks).  This provides a clean interface for unusual systems where the
  5484 internal and external process view of file names are different.
  5485 
  5486 * Pure: more efficient orders for basic syntactic entities: added
  5487 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  5488 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  5489 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  5490 orders now -- potential INCOMPATIBILITY for code that depends on a
  5491 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  5492 Library.sort_strings on result).
  5493 
  5494 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  5495 fold_types traverse types/terms from left to right, observing natural
  5496 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  5497 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  5498 
  5499 * Pure: name spaces have been refined, with significant changes of the
  5500 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  5501 to extern(_table).  The plain name entry path is superceded by a
  5502 general 'naming' context, which also includes the 'policy' to produce
  5503 a fully qualified name and external accesses of a fully qualified
  5504 name; NameSpace.extend is superceded by context dependent
  5505 Sign.declare_name.  Several theory and proof context operations modify
  5506 the naming context.  Especially note Theory.restore_naming and
  5507 ProofContext.restore_naming to get back to a sane state; note that
  5508 Theory.add_path is no longer sufficient to recover from
  5509 Theory.absolute_path in particular.
  5510 
  5511 * Pure: new flags short_names (default false) and unique_names
  5512 (default true) for controlling output of qualified names.  If
  5513 short_names is set, names are printed unqualified.  If unique_names is
  5514 reset, the name prefix is reduced to the minimum required to achieve
  5515 the original result when interning again, even if there is an overlap
  5516 with earlier declarations.
  5517 
  5518 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  5519 now 'extend', and 'merge' gets an additional Pretty.pp argument
  5520 (useful for printing error messages).  INCOMPATIBILITY.
  5521 
  5522 * Pure: major reorganization of the theory context.  Type Sign.sg and
  5523 Theory.theory are now identified, referring to the universal
  5524 Context.theory (see Pure/context.ML).  Actual signature and theory
  5525 content is managed as theory data.  The old code and interfaces were
  5526 spread over many files and structures; the new arrangement introduces
  5527 considerable INCOMPATIBILITY to gain more clarity:
  5528 
  5529   Context -- theory management operations (name, identity, inclusion,
  5530     parents, ancestors, merge, etc.), plus generic theory data;
  5531 
  5532   Sign -- logical signature and syntax operations (declaring consts,
  5533     types, etc.), plus certify/read for common entities;
  5534 
  5535   Theory -- logical theory operations (stating axioms, definitions,
  5536     oracles), plus a copy of logical signature operations (consts,
  5537     types, etc.); also a few basic management operations (Theory.copy,
  5538     Theory.merge, etc.)
  5539 
  5540 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  5541 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  5542 for convenience -- they merely return the theory.
  5543 
  5544 * Pure: type Type.tsig is superceded by theory in most interfaces.
  5545 
  5546 * Pure: the Isar proof context type is already defined early in Pure
  5547 as Context.proof (note that ProofContext.context and Proof.context are
  5548 aliases, where the latter is the preferred name).  This enables other
  5549 Isabelle components to refer to that type even before Isar is present.
  5550 
  5551 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  5552 typeK, constK, axiomK, oracleK), but provide explicit operations for
  5553 any of these kinds.  For example, Sign.intern typeK is now
  5554 Sign.intern_type, Theory.hide_space Sign.typeK is now
  5555 Theory.hide_types.  Also note that former
  5556 Theory.hide_classes/types/consts are now
  5557 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  5558 internalize their arguments!  INCOMPATIBILITY.
  5559 
  5560 * Pure: get_thm interface (of PureThy and ProofContext) expects
  5561 datatype thmref (with constructors Name and NameSelection) instead of
  5562 plain string -- INCOMPATIBILITY;
  5563 
  5564 * Pure: cases produced by proof methods specify options, where NONE
  5565 means to remove case bindings -- INCOMPATIBILITY in
  5566 (RAW_)METHOD_CASES.
  5567 
  5568 * Pure: the following operations retrieve axioms or theorems from a
  5569 theory node or theory hierarchy, respectively:
  5570 
  5571   Theory.axioms_of: theory -> (string * term) list
  5572   Theory.all_axioms_of: theory -> (string * term) list
  5573   PureThy.thms_of: theory -> (string * thm) list
  5574   PureThy.all_thms_of: theory -> (string * thm) list
  5575 
  5576 * Pure: print_tac now outputs the goal through the trace channel.
  5577 
  5578 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  5579 Reference Toplevel.debug (default false) controls detailed printing
  5580 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  5581 controls execution profiling -- set to 1 for time and 2 for space
  5582 (both increase the runtime).
  5583 
  5584 * Isar session: The initial use of ROOT.ML is now always timed,
  5585 i.e. the log will show the actual process times, in contrast to the
  5586 elapsed wall-clock time that the outer shell wrapper produces.
  5587 
  5588 * Simplifier: improved handling of bound variables (nameless
  5589 representation, avoid allocating new strings).  Simprocs that invoke
  5590 the Simplifier recursively should use Simplifier.inherit_bounds to
  5591 avoid local name clashes.  Failure to do so produces warnings
  5592 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  5593 for further details.
  5594 
  5595 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  5596 bindings for all theorems stored within a given theory; this may help
  5597 in porting non-Isar theories to Isar ones, while keeping ML proof
  5598 scripts for the time being.
  5599 
  5600 * ML operator HTML.with_charset specifies the charset begin used for
  5601 generated HTML files.  For example:
  5602 
  5603   HTML.with_charset "utf-8" use_thy "Hebrew";
  5604   HTML.with_charset "utf-8" use_thy "Chinese";
  5605 
  5606 
  5607 *** System ***
  5608 
  5609 * Allow symlinks to all proper Isabelle executables (Isabelle,
  5610 isabelle, isatool etc.).
  5611 
  5612 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  5613 isatool doc, isatool mkdir, display_drafts etc.).
  5614 
  5615 * isatool usedir: option -f allows specification of the ML file to be
  5616 used by Isabelle; default is ROOT.ML.
  5617 
  5618 * New isatool version outputs the version identifier of the Isabelle
  5619 distribution being used.
  5620 
  5621 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  5622 (containing Boolean satisfiability problems) into Isabelle/HOL
  5623 theories.
  5624 
  5625 
  5626 
  5627 New in Isabelle2004 (April 2004)
  5628 --------------------------------
  5629 
  5630 *** General ***
  5631 
  5632 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  5633   Replaces linorder.ML.
  5634 
  5635 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  5636   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  5637   (\<a>...\<z>), are now considered normal letters, and can therefore
  5638   be used anywhere where an ASCII letter (a...zA...Z) has until
  5639   now. COMPATIBILITY: This obviously changes the parsing of some
  5640   terms, especially where a symbol has been used as a binder, say
  5641   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  5642   as an identifier.  Fix it by inserting a space around former
  5643   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  5644   existing theory and ML files.
  5645 
  5646 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  5647 
  5648 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  5649   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  5650   a normal (but invisible) letter. For multiple letter subscripts repeat
  5651   \<^isub> like this: x\<^isub>1\<^isub>2.
  5652 
  5653 * Pure: There are now sub-/superscripts that can span more than one
  5654   character. Text between \<^bsub> and \<^esub> is set in subscript in
  5655   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  5656   superscript. The new control characters are not identifier parts.
  5657 
  5658 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5659   content of "..." to the latex file instead of \isacntrl... . The "..."
  5660   may consist of any printable characters excluding the end bracket >.
  5661 
  5662 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5663   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5664   declare constants "final", which prevents their being given a definition
  5665   later.  It is useful for constants whose behaviour is fixed axiomatically
  5666   rather than definitionally, such as the meta-logic connectives.
  5667 
  5668 * Pure: 'instance' now handles general arities with general sorts
  5669   (i.e. intersections of classes),
  5670 
  5671 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5672   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5673   It can be changed to alter the colors/layout of generated pages.
  5674 
  5675 
  5676 *** Isar ***
  5677 
  5678 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5679   cut_tac, subgoal_tac and thin_tac:
  5680   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5681     locales are no longer forced to write Isar proof scripts.
  5682     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5683     emulations.
  5684   - INCOMPATIBILITY: names of variables to be instantiated may no
  5685     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5686     This is consistent with the instantiation attribute "where".
  5687 
  5688 * Attributes "where" and "of":
  5689   - Now take type variables of instantiated theorem into account when reading
  5690     the instantiation string.  This fixes a bug that caused instantiated
  5691     theorems to have too special types in some circumstances.
  5692   - "where" permits explicit instantiations of type variables.
  5693 
  5694 * Calculation commands "moreover" and "also" no longer interfere with
  5695   current facts ("this"), admitting arbitrary combinations with "then"
  5696   and derived forms.
  5697 
  5698 * Locales:
  5699   - Goal statements involving the context element "includes" no longer
  5700     generate theorems with internal delta predicates (those ending on
  5701     "_axioms") in the premise.
  5702     Resolve particular premise with <locale>.intro to obtain old form.
  5703   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5704     specification and "includes" elements in goal statement.
  5705   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5706     [intro?] and [elim?] (respectively) by default.
  5707   - Experimental command for instantiation of locales in proof contexts:
  5708         instantiate <label>[<attrs>]: <loc>
  5709     Instantiates locale <loc> and adds all its theorems to the current context
  5710     taking into account their attributes.  Label and attrs are optional
  5711     modifiers, like in theorem declarations.  If present, names of
  5712     instantiated theorems are qualified with <label>, and the attributes
  5713     <attrs> are applied after any attributes these theorems might have already.
  5714       If the locale has assumptions, a chained fact of the form
  5715     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5716     are derived.  The command does not support old-style locales declared
  5717     with "locale (open)".
  5718       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5719 
  5720 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5721   (Isar) contexts.
  5722 
  5723 
  5724 *** HOL ***
  5725 
  5726 * Proof import: new image HOL4 contains the imported library from
  5727   the HOL4 system with about 2500 theorems. It is imported by
  5728   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5729   can be used like any other Isabelle image.  See
  5730   HOL/Import/HOL/README for more information.
  5731 
  5732 * Simplifier:
  5733   - Much improved handling of linear and partial orders.
  5734     Reasoners for linear and partial orders are set up for type classes
  5735     "linorder" and "order" respectively, and are added to the default simpset
  5736     as solvers.  This means that the simplifier can build transitivity chains
  5737     to solve goals from the assumptions.
  5738   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5739     of blast or auto after simplification become unnecessary because the goal
  5740     is solved by simplification already.
  5741 
  5742 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5743     all proved in axiomatic type classes for semirings, rings and fields.
  5744 
  5745 * Numerics:
  5746   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5747     now formalized using the Ring_and_Field theory mentioned above.
  5748   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5749     than before, because now they are set up once in a generic manner.
  5750   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5751     Look for the general versions in Ring_and_Field (and Power if they concern
  5752     exponentiation).
  5753 
  5754 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5755 
  5756 * Records:
  5757   - Record types are now by default printed with their type abbreviation
  5758     instead of the list of all field types. This can be configured via
  5759     the reference "print_record_type_abbr".
  5760   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5761     (not enabled by default).
  5762   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5763     EX x. x = sel r to True (not enabled by default).
  5764   - Tactic "record_split_simp_tac" to split and simplify records added.
  5765 
  5766 * 'specification' command added, allowing for definition by
  5767   specification.  There is also an 'ax_specification' command that
  5768   introduces the new constants axiomatically.
  5769 
  5770 * arith(_tac) is now able to generate counterexamples for reals as well.
  5771 
  5772 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5773 
  5774 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5775   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5776 
  5777 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5778   matrix theory to linear programming.
  5779 
  5780 * Unions and Intersections:
  5781   The latex output syntax of UN and INT has been changed
  5782   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5783   i.e. the index formulae has become a subscript.
  5784   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5785 
  5786 * Unions and Intersections over Intervals:
  5787   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5788   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5789   like in normal math, and corresponding versions for < and for intersection.
  5790 
  5791 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5792   lexicographic dictonary ordering has been added as "lexord".
  5793 
  5794 * ML: the legacy theory structures Int and List have been removed. They had
  5795   conflicted with ML Basis Library structures having the same names.
  5796 
  5797 * 'refute' command added to search for (finite) countermodels.  Only works
  5798   for a fragment of HOL.  The installation of an external SAT solver is
  5799   highly recommended.  See "HOL/Refute.thy" for details.
  5800 
  5801 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5802   formulae under an assignment of free variables to random values.
  5803   In contrast to 'refute', it can deal with inductive datatypes,
  5804   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5805   for examples.
  5806 
  5807 
  5808 *** HOLCF ***
  5809 
  5810 * Streams now come with concatenation and are part of the HOLCF image
  5811 
  5812 
  5813 
  5814 New in Isabelle2003 (May 2003)
  5815 ------------------------------
  5816 
  5817 *** General ***
  5818 
  5819 * Provers/simplifier:
  5820 
  5821   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5822     Assumptions are now subject to complete mutual simplification,
  5823     not just from left to right. The simplifier now preserves
  5824     the order of assumptions.
  5825 
  5826     Potential INCOMPATIBILITY:
  5827 
  5828     -- simp sometimes diverges where the old version did
  5829        not, e.g. invoking simp on the goal
  5830 
  5831         [| P (f x); y = x; f x = f y |] ==> Q
  5832 
  5833        now gives rise to the infinite reduction sequence
  5834 
  5835         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5836 
  5837        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5838        kind of problem.
  5839 
  5840     -- Tactics combining classical reasoner and simplification (such as auto)
  5841        are also affected by this change, because many of them rely on
  5842        simp. They may sometimes diverge as well or yield a different numbers
  5843        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5844        in case of problems. Sometimes subsequent calls to the classical
  5845        reasoner will fail because a preceeding call to the simplifier too
  5846        eagerly simplified the goal, e.g. deleted redundant premises.
  5847 
  5848   - The simplifier trace now shows the names of the applied rewrite rules
  5849 
  5850   - You can limit the number of recursive invocations of the simplifier
  5851     during conditional rewriting (where the simplifie tries to solve the
  5852     conditions before applying the rewrite rule):
  5853     ML "simp_depth_limit := n"
  5854     where n is an integer. Thus you can force termination where previously
  5855     the simplifier would diverge.
  5856 
  5857   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5858 
  5859   - No longer aborts on failed congruence proof.  Instead, the
  5860     congruence is ignored.
  5861 
  5862 * Pure: New generic framework for extracting programs from constructive
  5863   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5864   as HOL/Extraction for some case studies.
  5865 
  5866 * Pure: The main goal of the proof state is no longer shown by default, only
  5867 the subgoals. This behaviour is controlled by a new flag.
  5868    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5869 (ML: Proof.show_main_goal).
  5870 
  5871 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5872 rules whose conclusion matches subgoal 1:
  5873       PG menu: Isabelle/Isar -> Show me -> matching rules
  5874 The rules are ordered by how closely they match the subgoal.
  5875 In particular, rules that solve a subgoal outright are displayed first
  5876 (or rather last, the way they are printed).
  5877 (ML: ProofGeneral.print_intros())
  5878 
  5879 * Pure: New flag trace_unify_fail causes unification to print
  5880 diagnostic information (PG: in trace buffer) when it fails. This is
  5881 useful for figuring out why single step proofs like rule, erule or
  5882 assumption failed.
  5883 
  5884 * Pure: Locale specifications now produce predicate definitions
  5885 according to the body of text (covering assumptions modulo local
  5886 definitions); predicate "loc_axioms" covers newly introduced text,
  5887 while "loc" is cumulative wrt. all included locale expressions; the
  5888 latter view is presented only on export into the global theory
  5889 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5890 on the old view without predicates;
  5891 
  5892 * Pure: predefined locales "var" and "struct" are useful for sharing
  5893 parameters (as in CASL, for example); just specify something like
  5894 ``var x + var y + struct M'' as import;
  5895 
  5896 * Pure: improved thms_containing: proper indexing of facts instead of
  5897 raw theorems; check validity of results wrt. current name space;
  5898 include local facts of proof configuration (also covers active
  5899 locales), cover fixed variables in index; may use "_" in term
  5900 specification; an optional limit for the number of printed facts may
  5901 be given (the default is 40);
  5902 
  5903 * Pure: disallow duplicate fact bindings within new-style theory files
  5904 (batch-mode only);
  5905 
  5906 * Provers: improved induct method: assumptions introduced by case
  5907 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5908 the goal statement); "foo" still refers to all facts collectively;
  5909 
  5910 * Provers: the function blast.overloaded has been removed: all constants
  5911 are regarded as potentially overloaded, which improves robustness in exchange
  5912 for slight decrease in efficiency;
  5913 
  5914 * Provers/linorder: New generic prover for transitivity reasoning over
  5915 linear orders.  Note: this prover is not efficient!
  5916 
  5917 * Isar: preview of problems to finish 'show' now produce an error
  5918 rather than just a warning (in interactive mode);
  5919 
  5920 
  5921 *** HOL ***
  5922 
  5923 * arith(_tac)
  5924 
  5925  - Produces a counter example if it cannot prove a goal.
  5926    Note that the counter example may be spurious if the goal is not a formula
  5927    of quantifier-free linear arithmetic.
  5928    In ProofGeneral the counter example appears in the trace buffer.
  5929 
  5930  - Knows about div k and mod k where k is a numeral of type nat or int.
  5931 
  5932  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  5933    linear arithmetic fails. This takes account of quantifiers and divisibility.
  5934    Presburger arithmetic can also be called explicitly via presburger(_tac).
  5935 
  5936 * simp's arithmetic capabilities have been enhanced a bit: it now
  5937 takes ~= in premises into account (by performing a case split);
  5938 
  5939 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  5940 are distributed over a sum of terms;
  5941 
  5942 * New tactic "trans_tac" and method "trans" instantiate
  5943 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  5944 "<=", "<" and "=").
  5945 
  5946 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  5947 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  5948 
  5949 * 'typedef' command has new option "open" to suppress the set
  5950 definition;
  5951 
  5952 * functions Min and Max on finite sets have been introduced (theory
  5953 Finite_Set);
  5954 
  5955 * attribute [symmetric] now works for relations as well; it turns
  5956 (x,y) : R^-1 into (y,x) : R, and vice versa;
  5957 
  5958 * induct over a !!-quantified statement (say !!x1..xn):
  5959   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  5960 
  5961 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  5962 %x. None. Warning: empty_def now refers to the previously hidden definition
  5963 of the empty set.
  5964 
  5965 * Algebra: formalization of classical algebra.  Intended as base for
  5966 any algebraic development in Isabelle.  Currently covers group theory
  5967 (up to Sylow's theorem) and ring theory (Universal Property of
  5968 Univariate Polynomials).  Contributions welcome;
  5969 
  5970 * GroupTheory: deleted, since its material has been moved to Algebra;
  5971 
  5972 * Complex: new directory of the complex numbers with numeric constants,
  5973 nonstandard complex numbers, and some complex analysis, standard and
  5974 nonstandard (Jacques Fleuriot);
  5975 
  5976 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  5977 
  5978 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  5979 Fleuriot);
  5980 
  5981 * Real/HahnBanach: updated and adapted to locales;
  5982 
  5983 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  5984 Gray and Kramer);
  5985 
  5986 * UNITY: added the Meier-Sanders theory of progress sets;
  5987 
  5988 * MicroJava: bytecode verifier and lightweight bytecode verifier
  5989 as abstract algorithms, instantiated to the JVM;
  5990 
  5991 * Bali: Java source language formalization. Type system, operational
  5992 semantics, axiomatic semantics. Supported language features:
  5993 classes, interfaces, objects,virtual methods, static methods,
  5994 static/instance fields, arrays, access modifiers, definite
  5995 assignment, exceptions.
  5996 
  5997 
  5998 *** ZF ***
  5999 
  6000 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  6001 universe, etc.);
  6002 
  6003 * Main ZF: virtually all theories converted to new-style format;
  6004 
  6005 
  6006 *** ML ***
  6007 
  6008 * Pure: Tactic.prove provides sane interface for internal proofs;
  6009 omits the infamous "standard" operation, so this is more appropriate
  6010 than prove_goalw_cterm in many situations (e.g. in simprocs);
  6011 
  6012 * Pure: improved error reporting of simprocs;
  6013 
  6014 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  6015 up simprocs;
  6016 
  6017 
  6018 *** Document preparation ***
  6019 
  6020 * uses \par instead of \\ for line breaks in theory text. This may
  6021 shift some page breaks in large documents. To get the old behaviour
  6022 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  6023 
  6024 * minimized dependencies of isabelle.sty and isabellesym.sty on
  6025 other packages
  6026 
  6027 * \<euro> now needs package babel/greek instead of marvosym (which
  6028 broke \Rightarrow)
  6029 
  6030 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  6031 textcomp package)
  6032 
  6033 
  6034 
  6035 New in Isabelle2002 (March 2002)
  6036 --------------------------------
  6037 
  6038 *** Document preparation ***
  6039 
  6040 * greatly simplified document preparation setup, including more
  6041 graceful interpretation of isatool usedir -i/-d/-D options, and more
  6042 instructive isatool mkdir; users should basically be able to get
  6043 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  6044 users may run a separate document processing stage manually like this:
  6045 "isatool usedir -D output HOL Test && isatool document Test/output";
  6046 
  6047 * theory dependency graph may now be incorporated into documents;
  6048 isatool usedir -g true will produce session_graph.eps/.pdf for use
  6049 with \includegraphics of LaTeX;
  6050 
  6051 * proper spacing of consecutive markup elements, especially text
  6052 blocks after section headings;
  6053 
  6054 * support bold style (for single symbols only), input syntax is like
  6055 this: "\<^bold>\<alpha>" or "\<^bold>A";
  6056 
  6057 * \<bullet> is now output as bold \cdot by default, which looks much
  6058 better in printed text;
  6059 
  6060 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  6061 note that these symbols are currently unavailable in Proof General /
  6062 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  6063 
  6064 * isatool latex no longer depends on changed TEXINPUTS, instead
  6065 isatool document copies the Isabelle style files to the target
  6066 location;
  6067 
  6068 
  6069 *** Isar ***
  6070 
  6071 * Pure/Provers: improved proof by cases and induction;
  6072   - 'case' command admits impromptu naming of parameters (such as
  6073     "case (Suc n)");
  6074   - 'induct' method divinates rule instantiation from the inductive
  6075     claim; no longer requires excessive ?P bindings for proper
  6076     instantiation of cases;
  6077   - 'induct' method properly enumerates all possibilities of set/type
  6078     rules; as a consequence facts may be also passed through *type*
  6079     rules without further ado;
  6080   - 'induct' method now derives symbolic cases from the *rulified*
  6081     rule (before it used to rulify cases stemming from the internal
  6082     atomized version); this means that the context of a non-atomic
  6083     statement becomes is included in the hypothesis, avoiding the
  6084     slightly cumbersome show "PROP ?case" form;
  6085   - 'induct' may now use elim-style induction rules without chaining
  6086     facts, using ``missing'' premises from the goal state; this allows
  6087     rules stemming from inductive sets to be applied in unstructured
  6088     scripts, while still benefitting from proper handling of non-atomic
  6089     statements; NB: major inductive premises need to be put first, all
  6090     the rest of the goal is passed through the induction;
  6091   - 'induct' proper support for mutual induction involving non-atomic
  6092     rule statements (uses the new concept of simultaneous goals, see
  6093     below);
  6094   - append all possible rule selections, but only use the first
  6095     success (no backtracking);
  6096   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  6097   - undeclared rule case names default to numbers 1, 2, 3, ...;
  6098   - added 'print_induct_rules' (covered by help item in recent Proof
  6099     General versions);
  6100   - moved induct/cases attributes to Pure, methods to Provers;
  6101   - generic method setup instantiated for FOL and HOL;
  6102 
  6103 * Pure: support multiple simultaneous goal statements, for example
  6104 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  6105 meta-level mechanism, this acts as if several individual goals had
  6106 been stated separately; in particular common proof methods need to be
  6107 repeated in order to cover all claims; note that a single elimination
  6108 step is *not* sufficient to establish the two conjunctions, so this
  6109 fails:
  6110 
  6111   assume "A & B" then have A and B ..   (*".." fails*)
  6112 
  6113 better use "obtain" in situations as above; alternative refer to
  6114 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  6115 
  6116 * Pure: proper integration with ``locales''; unlike the original
  6117 version by Florian Kammller, Isar locales package high-level proof
  6118 contexts rather than raw logical ones (e.g. we admit to include
  6119 attributes everywhere); operations on locales include merge and
  6120 rename; support for implicit arguments (``structures''); simultaneous
  6121 type-inference over imports and text; see also HOL/ex/Locales.thy for
  6122 some examples;
  6123 
  6124 * Pure: the following commands have been ``localized'', supporting a
  6125 target locale specification "(in name)": 'lemma', 'theorem',
  6126 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  6127 stored both within the locale and at the theory level (exported and
  6128 qualified by the locale name);
  6129 
  6130 * Pure: theory goals may now be specified in ``long'' form, with
  6131 ad-hoc contexts consisting of arbitrary locale elements. for example
  6132 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  6133 definitions may be given, too); the result is a meta-level rule with
  6134 the context elements being discharged in the obvious way;
  6135 
  6136 * Pure: new proof command 'using' allows to augment currently used
  6137 facts after a goal statement ('using' is syntactically analogous to
  6138 'apply', but acts on the goal's facts only); this allows chained facts
  6139 to be separated into parts given before and after a claim, as in
  6140 ``from a and b have C using d and e <proof>'';
  6141 
  6142 * Pure: renamed "antecedent" case to "rule_context";
  6143 
  6144 * Pure: new 'judgment' command records explicit information about the
  6145 object-logic embedding (used by several tools internally); no longer
  6146 use hard-wired "Trueprop";
  6147 
  6148 * Pure: added 'corollary' command;
  6149 
  6150 * Pure: fixed 'token_translation' command;
  6151 
  6152 * Pure: removed obsolete 'exported' attribute;
  6153 
  6154 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  6155 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  6156 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  6157 
  6158 * Pure: method 'atomize' presents local goal premises as object-level
  6159 statements (atomic meta-level propositions); setup controlled via
  6160 rewrite rules declarations of 'atomize' attribute; example
  6161 application: 'induct' method with proper rule statements in improper
  6162 proof *scripts*;
  6163 
  6164 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  6165 now consider the syntactic context of assumptions, giving a better
  6166 chance to get type-inference of the arguments right (this is
  6167 especially important for locales);
  6168 
  6169 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  6170 mode;
  6171 
  6172 * Pure/obtain: the formal conclusion "thesis", being marked as
  6173 ``internal'', may no longer be reference directly in the text;
  6174 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  6175 situations;
  6176 
  6177 * Pure: generic 'sym' attribute which declares a rule both as pure
  6178 'elim?' and for the 'symmetric' operation;
  6179 
  6180 * Pure: marginal comments ``--'' may now occur just anywhere in the
  6181 text; the fixed correlation with particular command syntax has been
  6182 discontinued;
  6183 
  6184 * Pure: new method 'rules' is particularly well-suited for proof
  6185 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  6186 but often produces more compact proof terms with less detours;
  6187 
  6188 * Pure/Provers/classical: simplified integration with pure rule
  6189 attributes and methods; the classical "intro?/elim?/dest?"
  6190 declarations coincide with the pure ones; the "rule" method no longer
  6191 includes classically swapped intros; "intro" and "elim" methods no
  6192 longer pick rules from the context; also got rid of ML declarations
  6193 AddXIs/AddXEs/AddXDs; all of this has some potential for
  6194 INCOMPATIBILITY;
  6195 
  6196 * Provers/classical: attribute 'swapped' produces classical inversions
  6197 of introduction rules;
  6198 
  6199 * Provers/simplifier: 'simplified' attribute may refer to explicit
  6200 rules instead of full simplifier context; 'iff' attribute handles
  6201 conditional rules;
  6202 
  6203 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  6204 
  6205 * HOL: 'recdef' now fails on unfinished automated proofs, use
  6206 "(permissive)" option to recover old behavior;
  6207 
  6208 * HOL: 'inductive' no longer features separate (collective) attributes
  6209 for 'intros' (was found too confusing);
  6210 
  6211 * HOL: properly declared induction rules less_induct and
  6212 wf_induct_rule;
  6213 
  6214 
  6215 *** HOL ***
  6216 
  6217 * HOL: moved over to sane numeral syntax; the new policy is as
  6218 follows:
  6219 
  6220   - 0 and 1 are polymorphic constants, which are defined on any
  6221   numeric type (nat, int, real etc.);
  6222 
  6223   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  6224   binary representation internally;
  6225 
  6226   - type nat has special constructor Suc, and generally prefers Suc 0
  6227   over 1::nat and Suc (Suc 0) over 2::nat;
  6228 
  6229 This change may cause significant problems of INCOMPATIBILITY; here
  6230 are some hints on converting existing sources:
  6231 
  6232   - due to the new "num" token, "-0" and "-1" etc. are now atomic