NEWS
author huffman
Mon Aug 08 19:26:53 2011 -0700 (2011-08-08)
changeset 44081 730f7cced3a6
parent 44027 d01b3f045111
child 44086 c0847967a25a
permissions -rw-r--r--
rename type 'a net to 'a filter, following standard mathematical terminology
     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 * Classes bot and top require underlying partial order rather than preorder:
    64 uniqueness of bot and top is guaranteed.  INCOMPATIBILITY.
    65 
    66 * Class complete_lattice: generalized a couple of lemmas from sets;
    67 generalized theorems INF_cong and SUP_cong.  New type classes for complete
    68 boolean algebras and complete linear orders.  Lemmas Inf_less_iff,
    69 less_Sup_iff, INF_less_iff, less_SUP_iff now reside in class complete_linorder.
    70 Changes proposition of lemmas Inf_fun_def, Sup_fun_def, Inf_apply, Sup_apply.
    71 More consistent and less misunderstandable names:
    72   INFI_def ~> INF_def
    73   SUPR_def ~> SUP_def
    74   le_SUPI ~> le_SUP_I
    75   le_SUPI2 ~> le_SUP_I2
    76   le_INFI ~> le_INF_I
    77   INFI_bool_eq ~> INF_bool_eq
    78   SUPR_bool_eq ~> SUP_bool_eq
    79   INFI_apply ~> INF_apply
    80   SUPR_apply ~> SUP_apply
    81 INCOMPATIBILITY.
    82 
    83 * Theorem collections ball_simps and bex_simps do not contain theorems referring
    84 to UNION any longer;  these have been moved to collection UN_ball_bex_simps.
    85 INCOMPATIBILITY.
    86 
    87 * Archimedean_Field.thy:
    88     floor now is defined as parameter of a separate type class floor_ceiling.
    89  
    90 * Finite_Set.thy: more coherent development of fold_set locales:
    91 
    92     locale fun_left_comm ~> locale comp_fun_commute
    93     locale fun_left_comm_idem ~> locale comp_fun_idem
    94     
    95 Both use point-free characterisation; interpretation proofs may need adjustment.
    96 INCOMPATIBILITY.
    97 
    98 * Code generation:
    99   - theory Library/Code_Char_ord provides native ordering of characters
   100     in the target language.
   101   - commands code_module and code_library are legacy, use export_code instead. 
   102   - method evaluation is legacy, use method eval instead.
   103   - legacy evaluator "SML" is deactivated by default. To activate it, add the following
   104     line in your theory:
   105       setup {* Value.add_evaluator ("SML", Codegen.eval_term) *}
   106  
   107 * Declare ext [intro] by default.  Rare INCOMPATIBILITY.
   108 
   109 * Nitpick:
   110   - Added "need" and "total_consts" options.
   111   - Reintroduced "show_skolems" option by popular demand.
   112   - Renamed attribute: nitpick_def ~> nitpick_unfold.
   113     INCOMPATIBILITY.
   114 
   115 * Sledgehammer:
   116   - sledgehammer available_provers ~> sledgehammer supported_provers.
   117     INCOMPATIBILITY.
   118   - Added support for SNARK and ToFoF-E on SystemOnTPTP and for simply typed
   119     TPTP problems (TFF).
   120   - Added "preplay_timeout", "slicing", "type_enc", "sound", "max_mono_iters",
   121     and "max_new_mono_instances" options.
   122   - Removed "explicit_apply" and "full_types" options as well as "Full Types"
   123     Proof General menu item. INCOMPATIBILITY.
   124 
   125 * Metis:
   126   - Removed "metisF" -- use "metis" instead. INCOMPATIBILITY.
   127   - Obsoleted "metisFT" -- use "metis (full_types)" instead. INCOMPATIBILITY.
   128 
   129 * "try":
   130   - Renamed "try_methods" and added "simp:", "intro:", "dest:", and "elim:"
   131     options. INCOMPATIBILITY.
   132   - Introduced "try" that not only runs "try_methods" but also "solve_direct",
   133     "sledgehammer", "quickcheck", and "nitpick".
   134 
   135 * Quickcheck:
   136   - Added "eval" option to evaluate terms for the found counterexample
   137     (currently only supported by the default (exhaustive) tester)
   138   - Added post-processing of terms to obtain readable counterexamples
   139     (currently only supported by the default (exhaustive) tester)
   140   - New counterexample generator quickcheck[narrowing] enables
   141     narrowing-based testing.
   142     It requires that the Glasgow Haskell compiler is installed and
   143     its location is known to Isabelle with the environment variable
   144     ISABELLE_GHC.
   145   - Removed quickcheck tester "SML" based on the SML code generator
   146     from HOL-Library
   147 
   148 * Function package: discontinued option "tailrec".
   149 INCOMPATIBILITY. Use partial_function instead.
   150 
   151 * HOL-Probability:
   152   - Caratheodory's extension lemma is now proved for ring_of_sets.
   153   - Infinite products of probability measures are now available.
   154   - Use extended reals instead of positive extended reals.
   155     INCOMPATIBILITY.
   156 
   157 * Old recdef package has been moved to Library/Old_Recdef.thy, where it
   158 must be loaded explicitly.  INCOMPATIBILITY.
   159 
   160 * Well-founded recursion combinator "wfrec" has been moved to
   161 Library/Wfrec.thy. INCOMPATIBILITY.
   162 
   163 * Theory Library/Nat_Infinity has been renamed to Library/Extended_Nat.
   164 The names of the following types and constants have changed:
   165   inat (type) ~> enat
   166   Fin         ~> enat
   167   Infty       ~> infinity (overloaded)
   168   iSuc        ~> eSuc
   169   the_Fin     ~> the_enat
   170 Every theorem name containing "inat", "Fin", "Infty", or "iSuc" has
   171 been renamed accordingly.
   172 
   173 * Limits.thy: Type "'a net" has been renamed to "'a filter", in
   174 accordance with standard mathematical terminology. INCOMPATIBILITY.
   175 
   176 
   177 *** Document preparation ***
   178 
   179 * Discontinued special treatment of hard tabulators, which are better
   180 avoided in the first place.  Implicit tab-width is 1.
   181 
   182 * Antiquotation @{rail} layouts railroad syntax diagrams, see also
   183 isar-ref manual.
   184 
   185 * Antiquotation @{value} evaluates the given term and presents its result.
   186 
   187 * Localized \isabellestyle switch can be used within blocks or groups
   188 like this:
   189 
   190   \isabellestyle{it}  %preferred default
   191   {\isabellestylett @{text "typewriter stuff"}}
   192 
   193 * New term style "isub" as ad-hoc conversion of variables x1, y23 into
   194 subscripted form x\<^isub>1, y\<^isub>2\<^isub>3.
   195 
   196 * Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
   197 (e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).
   198 
   199 
   200 *** ML ***
   201 
   202 * The inner syntax of sort/type/term/prop supports inlined YXML
   203 representations within quoted string tokens.  By encoding logical
   204 entities via Term_XML (in ML or Scala) concrete syntax can be
   205 bypassed, which is particularly useful for producing bits of text
   206 under external program control.
   207 
   208 * Antiquotations for ML and document preparation are managed as theory
   209 data, which requires explicit setup.
   210 
   211 * Isabelle_Process.is_active allows tools to check if the official
   212 process wrapper is running (Isabelle/Scala/jEdit) or the old TTY loop
   213 (better known as Proof General).
   214 
   215 * Structure Proof_Context follows standard naming scheme.  Old
   216 ProofContext is still available for some time as legacy alias.
   217 
   218 * Structure Timing provides various operations for timing; supersedes
   219 former start_timing/end_timing etc.
   220 
   221 * Path.print is the official way to show file-system paths to users
   222 (including quotes etc.).
   223 
   224 * Inner syntax: identifiers in parse trees of generic categories
   225 "logic", "aprop", "idt" etc. carry position information (disguised as
   226 type constraints).  Occasional INCOMPATIBILITY with non-compliant
   227 translations that choke on unexpected type constraints.  Positions can
   228 be stripped in ML translations via Syntax.strip_positions /
   229 Syntax.strip_positions_ast, or via the syntax constant
   230 "_strip_positions" within parse trees.  As last resort, positions can
   231 be disabled via the configuration option Syntax.positions, which is
   232 called "syntax_positions" in Isar attribute syntax.
   233 
   234 * Discontinued special status of various ML structures that contribute
   235 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
   236 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
   237 refer directly to Ast.Constant, Lexicon.is_identifier,
   238 Syntax_Trans.mk_binder_tr etc.
   239 
   240 * Typed print translation: discontinued show_sorts argument, which is
   241 already available via context of "advanced" translation.
   242 
   243 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
   244 goal states; body tactic needs to address all subgoals uniformly.
   245 
   246 * Slightly more special eq_list/eq_set, with shortcut involving
   247 pointer equality (assumes that eq relation is reflexive).
   248 
   249 * Classical tactics use proper Proof.context instead of historic types
   250 claset/clasimpset.  Old-style declarations like addIs, addEs, addDs
   251 operate directly on Proof.context.  Raw type claset retains its use as
   252 snapshot of the classical context, which can be recovered via
   253 (put_claset HOL_cs) etc.  Type clasimpset has been discontinued.
   254 INCOMPATIBILITY, classical tactics and derived proof methods require
   255 proper Proof.context.
   256 
   257 * Scala layer provides JVM method invocation service for static
   258 methods of type (String)String, see Invoke_Scala.method in ML.
   259 For example:
   260 
   261   Invoke_Scala.method "java.lang.System.getProperty" "java.home"
   262 
   263 
   264 
   265 New in Isabelle2011 (January 2011)
   266 ----------------------------------
   267 
   268 *** General ***
   269 
   270 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
   271 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
   272 useful tooltips and hyperlinks produced from its static analysis.  The
   273 bundled component provides an executable Isabelle tool that can be run
   274 like this:
   275 
   276   Isabelle2011/bin/isabelle jedit
   277 
   278 * Significantly improved Isabelle/Isar implementation manual.
   279 
   280 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
   281 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
   282 while the default heap location within that directory lacks that extra
   283 suffix.  This isolates multiple Isabelle installations from each
   284 other, avoiding problems with old settings in new versions.
   285 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
   286 
   287 * Source files are always encoded as UTF-8, instead of old-fashioned
   288 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
   289 the following package declarations:
   290 
   291   \usepackage[utf8]{inputenc}
   292   \usepackage{textcomp}
   293 
   294 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
   295 a Unicode character is treated as a single symbol, not a sequence of
   296 non-ASCII bytes as before.  Since Isabelle/ML string literals may
   297 contain symbols without further backslash escapes, Unicode can now be
   298 used here as well.  Recall that Symbol.explode in ML provides a
   299 consistent view on symbols, while raw explode (or String.explode)
   300 merely give a byte-oriented representation.
   301 
   302 * Theory loader: source files are primarily located via the master
   303 directory of each theory node (where the .thy file itself resides).
   304 The global load path is still partially available as legacy feature.
   305 Minor INCOMPATIBILITY due to subtle change in file lookup: use
   306 explicit paths, relatively to the theory.
   307 
   308 * Special treatment of ML file names has been discontinued.
   309 Historically, optional extensions .ML or .sml were added on demand --
   310 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
   311 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
   312 
   313 * Various options that affect pretty printing etc. are now properly
   314 handled within the context via configuration options, instead of
   315 unsynchronized references or print modes.  There are both ML Config.T
   316 entities and Isar declaration attributes to access these.
   317 
   318   ML (Config.T)                 Isar (attribute)
   319 
   320   eta_contract                  eta_contract
   321   show_brackets                 show_brackets
   322   show_sorts                    show_sorts
   323   show_types                    show_types
   324   show_question_marks           show_question_marks
   325   show_consts                   show_consts
   326   show_abbrevs                  show_abbrevs
   327 
   328   Syntax.ast_trace              syntax_ast_trace
   329   Syntax.ast_stat               syntax_ast_stat
   330   Syntax.ambiguity_level        syntax_ambiguity_level
   331 
   332   Goal_Display.goals_limit      goals_limit
   333   Goal_Display.show_main_goal   show_main_goal
   334 
   335   Method.rule_trace             rule_trace
   336 
   337   Thy_Output.display            thy_output_display
   338   Thy_Output.quotes             thy_output_quotes
   339   Thy_Output.indent             thy_output_indent
   340   Thy_Output.source             thy_output_source
   341   Thy_Output.break              thy_output_break
   342 
   343 Note that corresponding "..._default" references in ML may only be
   344 changed globally at the ROOT session setup, but *not* within a theory.
   345 The option "show_abbrevs" supersedes the former print mode
   346 "no_abbrevs" with inverted meaning.
   347 
   348 * More systematic naming of some configuration options.
   349 INCOMPATIBILITY.
   350 
   351   trace_simp  ~>  simp_trace
   352   debug_simp  ~>  simp_debug
   353 
   354 * Support for real valued configuration options, using simplistic
   355 floating-point notation that coincides with the inner syntax for
   356 float_token.
   357 
   358 * Support for real valued preferences (with approximative PGIP type):
   359 front-ends need to accept "pgint" values in float notation.
   360 INCOMPATIBILITY.
   361 
   362 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
   363 DejaVu Sans.
   364 
   365 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   366 
   367 
   368 *** Pure ***
   369 
   370 * Command 'type_synonym' (with single argument) replaces somewhat
   371 outdated 'types', which is still available as legacy feature for some
   372 time.
   373 
   374 * Command 'nonterminal' (with 'and' separated list of arguments)
   375 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
   376 
   377 * Command 'notepad' replaces former 'example_proof' for
   378 experimentation in Isar without any result.  INCOMPATIBILITY.
   379 
   380 * Locale interpretation commands 'interpret' and 'sublocale' accept
   381 lists of equations to map definitions in a locale to appropriate
   382 entities in the context of the interpretation.  The 'interpretation'
   383 command already provided this functionality.
   384 
   385 * Diagnostic command 'print_dependencies' prints the locale instances
   386 that would be activated if the specified expression was interpreted in
   387 the current context.  Variant "print_dependencies!" assumes a context
   388 without interpretations.
   389 
   390 * Diagnostic command 'print_interps' prints interpretations in proofs
   391 in addition to interpretations in theories.
   392 
   393 * Discontinued obsolete 'global' and 'local' commands to manipulate
   394 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
   395 Sign.root_path and Sign.local_path may be applied directly where this
   396 feature is still required for historical reasons.
   397 
   398 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
   399 'definition' instead.
   400 
   401 * The "prems" fact, which refers to the accidental collection of
   402 foundational premises in the context, is now explicitly marked as
   403 legacy feature and will be discontinued soon.  Consider using "assms"
   404 of the head statement or reference facts by explicit names.
   405 
   406 * Document antiquotations @{class} and @{type} print classes and type
   407 constructors.
   408 
   409 * Document antiquotation @{file} checks file/directory entries within
   410 the local file system.
   411 
   412 
   413 *** HOL ***
   414 
   415 * Coercive subtyping: functions can be declared as coercions and type
   416 inference will add them as necessary upon input of a term.  Theory
   417 Complex_Main declares real :: nat => real and real :: int => real as
   418 coercions. A coercion function f is declared like this:
   419 
   420   declare [[coercion f]]
   421 
   422 To lift coercions through type constructors (e.g. from nat => real to
   423 nat list => real list), map functions can be declared, e.g.
   424 
   425   declare [[coercion_map map]]
   426 
   427 Currently coercion inference is activated only in theories including
   428 real numbers, i.e. descendants of Complex_Main.  This is controlled by
   429 the configuration option "coercion_enabled", e.g. it can be enabled in
   430 other theories like this:
   431 
   432   declare [[coercion_enabled]]
   433 
   434 * Command 'partial_function' provides basic support for recursive
   435 function definitions over complete partial orders.  Concrete instances
   436 are provided for i) the option type, ii) tail recursion on arbitrary
   437 types, and iii) the heap monad of Imperative_HOL.  See
   438 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
   439 for examples.
   440 
   441 * Function package: f.psimps rules are no longer implicitly declared
   442 as [simp].  INCOMPATIBILITY.
   443 
   444 * Datatype package: theorems generated for executable equality (class
   445 "eq") carry proper names and are treated as default code equations.
   446 
   447 * Inductive package: now offers command 'inductive_simps' to
   448 automatically derive instantiated and simplified equations for
   449 inductive predicates, similar to 'inductive_cases'.
   450 
   451 * Command 'enriched_type' allows to register properties of the
   452 functorial structure of types.
   453 
   454 * Improved infrastructure for term evaluation using code generator
   455 techniques, in particular static evaluation conversions.
   456 
   457 * Code generator: Scala (2.8 or higher) has been added to the target
   458 languages.
   459 
   460 * Code generator: globbing constant expressions "*" and "Theory.*"
   461 have been replaced by the more idiomatic "_" and "Theory._".
   462 INCOMPATIBILITY.
   463 
   464 * Code generator: export_code without explicit file declaration prints
   465 to standard output.  INCOMPATIBILITY.
   466 
   467 * Code generator: do not print function definitions for case
   468 combinators any longer.
   469 
   470 * Code generator: simplification with rules determined with
   471 src/Tools/Code/code_simp.ML and method "code_simp".
   472 
   473 * Code generator for records: more idiomatic representation of record
   474 types.  Warning: records are not covered by ancient SML code
   475 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
   476 rep_datatype declaration helps to succeed then:
   477 
   478   record 'a foo = ...
   479   ...
   480   rep_datatype foo_ext ...
   481 
   482 * Records: logical foundation type for records does not carry a
   483 '_type' suffix any longer (obsolete due to authentic syntax).
   484 INCOMPATIBILITY.
   485 
   486 * Quickcheck now by default uses exhaustive testing instead of random
   487 testing.  Random testing can be invoked by "quickcheck [random]",
   488 exhaustive testing by "quickcheck [exhaustive]".
   489 
   490 * Quickcheck instantiates polymorphic types with small finite
   491 datatypes by default. This enables a simple execution mechanism to
   492 handle quantifiers and function equality over the finite datatypes.
   493 
   494 * Quickcheck random generator has been renamed from "code" to
   495 "random".  INCOMPATIBILITY.
   496 
   497 * Quickcheck now has a configurable time limit which is set to 30
   498 seconds by default. This can be changed by adding [timeout = n] to the
   499 quickcheck command. The time limit for Auto Quickcheck is still set
   500 independently.
   501 
   502 * Quickcheck in locales considers interpretations of that locale for
   503 counter example search.
   504 
   505 * Sledgehammer:
   506   - Added "smt" and "remote_smt" provers based on the "smt" proof
   507     method. See the Sledgehammer manual for details ("isabelle doc
   508     sledgehammer").
   509   - Renamed commands:
   510     sledgehammer atp_info ~> sledgehammer running_provers
   511     sledgehammer atp_kill ~> sledgehammer kill_provers
   512     sledgehammer available_atps ~> sledgehammer available_provers
   513     INCOMPATIBILITY.
   514   - Renamed options:
   515     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
   516     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
   517     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
   518     (and "ms" and "min" are no longer supported)
   519     INCOMPATIBILITY.
   520 
   521 * Nitpick:
   522   - Renamed options:
   523     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
   524     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
   525     INCOMPATIBILITY.
   526   - Added support for partial quotient types.
   527   - Added local versions of the "Nitpick.register_xxx" functions.
   528   - Added "whack" option.
   529   - Allow registration of quotient types as codatatypes.
   530   - Improved "merge_type_vars" option to merge more types.
   531   - Removed unsound "fast_descrs" option.
   532   - Added custom symmetry breaking for datatypes, making it possible to reach
   533     higher cardinalities.
   534   - Prevent the expansion of too large definitions.
   535 
   536 * Proof methods "metis" and "meson" now have configuration options
   537 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
   538 to diagnose these tools. E.g.
   539 
   540     using [[metis_trace = true]]
   541 
   542 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
   543 manually as command 'solve_direct'.
   544 
   545 * The default SMT solver Z3 must be enabled explicitly (due to
   546 licensing issues) by setting the environment variable
   547 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
   548 commercial applications, the SMT solver CVC3 is provided as fall-back;
   549 changing the SMT solver is done via the configuration option
   550 "smt_solver".
   551 
   552 * Remote SMT solvers need to be referred to by the "remote_" prefix,
   553 i.e. "remote_cvc3" and "remote_z3".
   554 
   555 * Added basic SMT support for datatypes, records, and typedefs using
   556 the oracle mode (no proofs).  Direct support of pairs has been dropped
   557 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
   558 support for a similar behavior).  Minor INCOMPATIBILITY.
   559 
   560 * Changed SMT configuration options:
   561   - Renamed:
   562     z3_proofs ~> smt_oracle (with inverted meaning)
   563     z3_trace_assms ~> smt_trace_used_facts
   564     INCOMPATIBILITY.
   565   - Added:
   566     smt_verbose
   567     smt_random_seed
   568     smt_datatypes
   569     smt_infer_triggers
   570     smt_monomorph_limit
   571     cvc3_options
   572     remote_cvc3_options
   573     remote_z3_options
   574     yices_options
   575 
   576 * Boogie output files (.b2i files) need to be declared in the theory
   577 header.
   578 
   579 * Simplification procedure "list_to_set_comprehension" rewrites list
   580 comprehensions applied to List.set to set comprehensions.  Occasional
   581 INCOMPATIBILITY, may be deactivated like this:
   582 
   583   declare [[simproc del: list_to_set_comprehension]]
   584 
   585 * Removed old version of primrec package.  INCOMPATIBILITY.
   586 
   587 * Removed simplifier congruence rule of "prod_case", as has for long
   588 been the case with "split".  INCOMPATIBILITY.
   589 
   590 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
   591 
   592 * Removed [split_format ... and ... and ...] version of
   593 [split_format].  Potential INCOMPATIBILITY.
   594 
   595 * Predicate "sorted" now defined inductively, with nice induction
   596 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
   597 
   598 * Constant "contents" renamed to "the_elem", to free the generic name
   599 contents for other uses.  INCOMPATIBILITY.
   600 
   601 * Renamed class eq and constant eq (for code generation) to class
   602 equal and constant equal, plus renaming of related facts and various
   603 tuning.  INCOMPATIBILITY.
   604 
   605 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
   606 
   607 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
   608 INCOMPATIBILITY.
   609 
   610 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
   611 avoid confusion with finite sets.  INCOMPATIBILITY.
   612 
   613 * Abandoned locales equiv, congruent and congruent2 for equivalence
   614 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
   615 for congruent(2)).
   616 
   617 * Some previously unqualified names have been qualified:
   618 
   619   types
   620     bool ~> HOL.bool
   621     nat ~> Nat.nat
   622 
   623   constants
   624     Trueprop ~> HOL.Trueprop
   625     True ~> HOL.True
   626     False ~> HOL.False
   627     op & ~> HOL.conj
   628     op | ~> HOL.disj
   629     op --> ~> HOL.implies
   630     op = ~> HOL.eq
   631     Not ~> HOL.Not
   632     The ~> HOL.The
   633     All ~> HOL.All
   634     Ex ~> HOL.Ex
   635     Ex1 ~> HOL.Ex1
   636     Let ~> HOL.Let
   637     If ~> HOL.If
   638     Ball ~> Set.Ball
   639     Bex ~> Set.Bex
   640     Suc ~> Nat.Suc
   641     Pair ~> Product_Type.Pair
   642     fst ~> Product_Type.fst
   643     snd ~> Product_Type.snd
   644     curry ~> Product_Type.curry
   645     op : ~> Set.member
   646     Collect ~> Set.Collect
   647 
   648 INCOMPATIBILITY.
   649 
   650 * More canonical naming convention for some fundamental definitions:
   651 
   652     bot_bool_eq ~> bot_bool_def
   653     top_bool_eq ~> top_bool_def
   654     inf_bool_eq ~> inf_bool_def
   655     sup_bool_eq ~> sup_bool_def
   656     bot_fun_eq  ~> bot_fun_def
   657     top_fun_eq  ~> top_fun_def
   658     inf_fun_eq  ~> inf_fun_def
   659     sup_fun_eq  ~> sup_fun_def
   660 
   661 INCOMPATIBILITY.
   662 
   663 * More stylized fact names:
   664 
   665   expand_fun_eq ~> fun_eq_iff
   666   expand_set_eq ~> set_eq_iff
   667   set_ext       ~> set_eqI
   668   nat_number    ~> eval_nat_numeral
   669 
   670 INCOMPATIBILITY.
   671 
   672 * Refactoring of code-generation specific operations in theory List:
   673 
   674   constants
   675     null ~> List.null
   676 
   677   facts
   678     mem_iff ~> member_def
   679     null_empty ~> null_def
   680 
   681 INCOMPATIBILITY.  Note that these were not supposed to be used
   682 regularly unless for striking reasons; their main purpose was code
   683 generation.
   684 
   685 Various operations from the Haskell prelude are used for generating
   686 Haskell code.
   687 
   688 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
   689 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
   690 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
   691 
   692 * Abolished some non-alphabetic type names: "prod" and "sum" replace
   693 "*" and "+" respectively.  INCOMPATIBILITY.
   694 
   695 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
   696 "Sum_Type.Plus" instead.
   697 
   698 * Constant "split" has been merged with constant "prod_case"; names of
   699 ML functions, facts etc. involving split have been retained so far,
   700 though.  INCOMPATIBILITY.
   701 
   702 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
   703 instead.  INCOMPATIBILITY.
   704 
   705 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
   706 INCOMPATIBILITY.
   707 
   708 * Former theory Library/Enum is now part of the HOL-Main image.
   709 INCOMPATIBILITY: all constants of the Enum theory now have to be
   710 referred to by its qualified name.
   711 
   712   enum    ~>  Enum.enum
   713   nlists  ~>  Enum.nlists
   714   product ~>  Enum.product
   715 
   716 * Theory Library/Monad_Syntax provides do-syntax for monad types.
   717 Syntax in Library/State_Monad has been changed to avoid ambiguities.
   718 INCOMPATIBILITY.
   719 
   720 * Theory Library/SetsAndFunctions has been split into
   721 Library/Function_Algebras and Library/Set_Algebras; canonical names
   722 for instance definitions for functions; various improvements.
   723 INCOMPATIBILITY.
   724 
   725 * Theory Library/Multiset provides stable quicksort implementation of
   726 sort_key.
   727 
   728 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
   729 INCOMPATIBILITY.
   730 
   731 * Session Multivariate_Analysis: introduced a type class for euclidean
   732 space.  Most theorems are now stated in terms of euclidean spaces
   733 instead of finite cartesian products.
   734 
   735   types
   736     real ^ 'n ~>  'a::real_vector
   737               ~>  'a::euclidean_space
   738               ~>  'a::ordered_euclidean_space
   739         (depends on your needs)
   740 
   741   constants
   742      _ $ _        ~> _ $$ _
   743      \<chi> x. _  ~> \<chi>\<chi> x. _
   744      CARD('n)     ~> DIM('a)
   745 
   746 Also note that the indices are now natural numbers and not from some
   747 finite type. Finite cartesian products of euclidean spaces, products
   748 of euclidean spaces the real and complex numbers are instantiated to
   749 be euclidean_spaces.  INCOMPATIBILITY.
   750 
   751 * Session Probability: introduced pextreal as positive extended real
   752 numbers.  Use pextreal as value for measures.  Introduce the
   753 Radon-Nikodym derivative, product spaces and Fubini's theorem for
   754 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
   755 the integral in Multivariate Analysis.  INCOMPATIBILITY.
   756 
   757 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   758 INCOMPATIBILITY.
   759 
   760 * Session SPARK (with image HOL-SPARK) provides commands to load and
   761 prove verification conditions generated by the SPARK Ada program
   762 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
   763 
   764 
   765 *** HOL-Algebra ***
   766 
   767 * Theorems for additive ring operations (locale abelian_monoid and
   768 descendants) are generated by interpretation from their multiplicative
   769 counterparts.  Names (in particular theorem names) have the mandatory
   770 qualifier 'add'.  Previous theorem names are redeclared for
   771 compatibility.
   772 
   773 * Structure "int_ring" is now an abbreviation (previously a
   774 definition).  This fits more natural with advanced interpretations.
   775 
   776 
   777 *** HOLCF ***
   778 
   779 * The domain package now runs in definitional mode by default: The
   780 former command 'new_domain' is now called 'domain'.  To use the domain
   781 package in its original axiomatic mode, use 'domain (unsafe)'.
   782 INCOMPATIBILITY.
   783 
   784 * The new class "domain" is now the default sort.  Class "predomain"
   785 is an unpointed version of "domain". Theories can be updated by
   786 replacing sort annotations as shown below.  INCOMPATIBILITY.
   787 
   788   'a::type ~> 'a::countable
   789   'a::cpo  ~> 'a::predomain
   790   'a::pcpo ~> 'a::domain
   791 
   792 * The old type class "rep" has been superseded by class "domain".
   793 Accordingly, users of the definitional package must remove any
   794 "default_sort rep" declarations.  INCOMPATIBILITY.
   795 
   796 * The domain package (definitional mode) now supports unpointed
   797 predomain argument types, as long as they are marked 'lazy'. (Strict
   798 arguments must be in class "domain".) For example, the following
   799 domain definition now works:
   800 
   801   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
   802 
   803 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
   804 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
   805 'a option, and 'a list.  Additionally, it configures fixrec and the
   806 domain package to work with these types.  For example:
   807 
   808   fixrec isInl :: "('a + 'b) u -> tr"
   809     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
   810 
   811   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
   812 
   813 * The "(permissive)" option of fixrec has been replaced with a
   814 per-equation "(unchecked)" option. See
   815 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
   816 
   817 * The "bifinite" class no longer fixes a constant "approx"; the class
   818 now just asserts that such a function exists.  INCOMPATIBILITY.
   819 
   820 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
   821 defines an embedding of type 'a defl into udom by default; instances
   822 of "bifinite" and "domain" classes are available in
   823 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
   824 
   825 * The syntax "REP('a)" has been replaced with "DEFL('a)".
   826 
   827 * The predicate "directed" has been removed.  INCOMPATIBILITY.
   828 
   829 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
   830 
   831 * The function "cprod_map" has been renamed to "prod_map".
   832 INCOMPATIBILITY.
   833 
   834 * The monadic bind operator on each powerdomain has new binder syntax
   835 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
   836 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
   837 
   838 * The infix syntax for binary union on each powerdomain has changed
   839 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
   840 syntax.  INCOMPATIBILITY.
   841 
   842 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
   843 still supported as an input translation.
   844 
   845 * Renamed some theorems (the original names are also still available).
   846 
   847   expand_fun_below   ~> fun_below_iff
   848   below_fun_ext      ~> fun_belowI
   849   expand_cfun_eq     ~> cfun_eq_iff
   850   ext_cfun           ~> cfun_eqI
   851   expand_cfun_below  ~> cfun_below_iff
   852   below_cfun_ext     ~> cfun_belowI
   853   cont2cont_Rep_CFun ~> cont2cont_APP
   854 
   855 * The Abs and Rep functions for various types have changed names.
   856 Related theorem names have also changed to match. INCOMPATIBILITY.
   857 
   858   Rep_CFun  ~> Rep_cfun
   859   Abs_CFun  ~> Abs_cfun
   860   Rep_Sprod ~> Rep_sprod
   861   Abs_Sprod ~> Abs_sprod
   862   Rep_Ssum  ~> Rep_ssum
   863   Abs_Ssum  ~> Abs_ssum
   864 
   865 * Lemmas with names of the form *_defined_iff or *_strict_iff have
   866 been renamed to *_bottom_iff.  INCOMPATIBILITY.
   867 
   868 * Various changes to bisimulation/coinduction with domain package:
   869 
   870   - Definitions of "bisim" constants no longer mention definedness.
   871   - With mutual recursion, "bisim" predicate is now curried.
   872   - With mutual recursion, each type gets a separate coind theorem.
   873   - Variable names in bisim_def and coinduct rules have changed.
   874 
   875 INCOMPATIBILITY.
   876 
   877 * Case combinators generated by the domain package for type "foo" are
   878 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
   879 
   880 * Several theorems have been renamed to more accurately reflect the
   881 names of constants and types involved.  INCOMPATIBILITY.
   882 
   883   thelub_const    ~> lub_const
   884   lub_const       ~> is_lub_const
   885   thelubI         ~> lub_eqI
   886   is_lub_lub      ~> is_lubD2
   887   lubI            ~> is_lub_lub
   888   unique_lub      ~> is_lub_unique
   889   is_ub_lub       ~> is_lub_rangeD1
   890   lub_bin_chain   ~> is_lub_bin_chain
   891   lub_fun         ~> is_lub_fun
   892   thelub_fun      ~> lub_fun
   893   thelub_cfun     ~> lub_cfun
   894   thelub_Pair     ~> lub_Pair
   895   lub_cprod       ~> is_lub_prod
   896   thelub_cprod    ~> lub_prod
   897   minimal_cprod   ~> minimal_prod
   898   inst_cprod_pcpo ~> inst_prod_pcpo
   899   UU_I            ~> bottomI
   900   compact_UU      ~> compact_bottom
   901   deflation_UU    ~> deflation_bottom
   902   finite_deflation_UU ~> finite_deflation_bottom
   903 
   904 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
   905 
   906   sq_ord_less_eq_trans ~> below_eq_trans
   907   sq_ord_eq_less_trans ~> eq_below_trans
   908   refl_less            ~> below_refl
   909   trans_less           ~> below_trans
   910   antisym_less         ~> below_antisym
   911   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
   912   box_less             ~> box_below
   913   rev_trans_less       ~> rev_below_trans
   914   not_less2not_eq      ~> not_below2not_eq
   915   less_UU_iff          ~> below_UU_iff
   916   flat_less_iff        ~> flat_below_iff
   917   adm_less             ~> adm_below
   918   adm_not_less         ~> adm_not_below
   919   adm_compact_not_less ~> adm_compact_not_below
   920   less_fun_def         ~> below_fun_def
   921   expand_fun_less      ~> fun_below_iff
   922   less_fun_ext         ~> fun_belowI
   923   less_discr_def       ~> below_discr_def
   924   discr_less_eq        ~> discr_below_eq
   925   less_unit_def        ~> below_unit_def
   926   less_cprod_def       ~> below_prod_def
   927   prod_lessI           ~> prod_belowI
   928   Pair_less_iff        ~> Pair_below_iff
   929   fst_less_iff         ~> fst_below_iff
   930   snd_less_iff         ~> snd_below_iff
   931   expand_cfun_less     ~> cfun_below_iff
   932   less_cfun_ext        ~> cfun_belowI
   933   injection_less       ~> injection_below
   934   less_up_def          ~> below_up_def
   935   not_Iup_less         ~> not_Iup_below
   936   Iup_less             ~> Iup_below
   937   up_less              ~> up_below
   938   Def_inject_less_eq   ~> Def_below_Def
   939   Def_less_is_eq       ~> Def_below_iff
   940   spair_less_iff       ~> spair_below_iff
   941   less_sprod           ~> below_sprod
   942   spair_less           ~> spair_below
   943   sfst_less_iff        ~> sfst_below_iff
   944   ssnd_less_iff        ~> ssnd_below_iff
   945   fix_least_less       ~> fix_least_below
   946   dist_less_one        ~> dist_below_one
   947   less_ONE             ~> below_ONE
   948   ONE_less_iff         ~> ONE_below_iff
   949   less_sinlD           ~> below_sinlD
   950   less_sinrD           ~> below_sinrD
   951 
   952 
   953 *** FOL and ZF ***
   954 
   955 * All constant names are now qualified internally and use proper
   956 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
   957 
   958 
   959 *** ML ***
   960 
   961 * Antiquotation @{assert} inlines a function bool -> unit that raises
   962 Fail if the argument is false.  Due to inlining the source position of
   963 failed assertions is included in the error output.
   964 
   965 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
   966 text is in practice always evaluated with a stable theory checkpoint.
   967 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
   968 
   969 * Antiquotation @{theory A} refers to theory A from the ancestry of
   970 the current context, not any accidental theory loader state as before.
   971 Potential INCOMPATIBILITY, subtle change in semantics.
   972 
   973 * Syntax.pretty_priority (default 0) configures the required priority
   974 of pretty-printed output and thus affects insertion of parentheses.
   975 
   976 * Syntax.default_root (default "any") configures the inner syntax
   977 category (nonterminal symbol) for parsing of terms.
   978 
   979 * Former exception Library.UnequalLengths now coincides with
   980 ListPair.UnequalLengths.
   981 
   982 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
   983 main functionality is provided by structure Simplifier.
   984 
   985 * Renamed raw "explode" function to "raw_explode" to emphasize its
   986 meaning.  Note that internally to Isabelle, Symbol.explode is used in
   987 almost all situations.
   988 
   989 * Discontinued obsolete function sys_error and exception SYS_ERROR.
   990 See implementation manual for further details on exceptions in
   991 Isabelle/ML.
   992 
   993 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
   994 meaning.
   995 
   996 * Renamed structure PureThy to Pure_Thy and moved most of its
   997 operations to structure Global_Theory, to emphasize that this is
   998 rarely-used global-only stuff.
   999 
  1000 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
  1001 instead (or tracing for high-volume output).
  1002 
  1003 * Configuration option show_question_marks only affects regular pretty
  1004 printing of types and terms, not raw Term.string_of_vname.
  1005 
  1006 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
  1007 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
  1008 @{thms} for most purposes.
  1009 
  1010 * ML structure Unsynchronized is never opened, not even in Isar
  1011 interaction mode as before.  Old Unsynchronized.set etc. have been
  1012 discontinued -- use plain := instead.  This should be *rare* anyway,
  1013 since modern tools always work via official context data, notably
  1014 configuration options.
  1015 
  1016 * Parallel and asynchronous execution requires special care concerning
  1017 interrupts.  Structure Exn provides some convenience functions that
  1018 avoid working directly with raw Interrupt.  User code must not absorb
  1019 interrupts -- intermediate handling (for cleanup etc.) needs to be
  1020 followed by re-raising of the original exception.  Another common
  1021 source of mistakes are "handle _" patterns, which make the meaning of
  1022 the program subject to physical effects of the environment.
  1023 
  1024 
  1025 
  1026 New in Isabelle2009-2 (June 2010)
  1027 ---------------------------------
  1028 
  1029 *** General ***
  1030 
  1031 * Authentic syntax for *all* logical entities (type classes, type
  1032 constructors, term constants): provides simple and robust
  1033 correspondence between formal entities and concrete syntax.  Within
  1034 the parse tree / AST representations, "constants" are decorated by
  1035 their category (class, type, const) and spelled out explicitly with
  1036 their full internal name.
  1037 
  1038 Substantial INCOMPATIBILITY concerning low-level syntax declarations
  1039 and translations (translation rules and translation functions in ML).
  1040 Some hints on upgrading:
  1041 
  1042   - Many existing uses of 'syntax' and 'translations' can be replaced
  1043     by more modern 'type_notation', 'notation' and 'abbreviation',
  1044     which are independent of this issue.
  1045 
  1046   - 'translations' require markup within the AST; the term syntax
  1047     provides the following special forms:
  1048 
  1049       CONST c   -- produces syntax version of constant c from context
  1050       XCONST c  -- literally c, checked as constant from context
  1051       c         -- literally c, if declared by 'syntax'
  1052 
  1053     Plain identifiers are treated as AST variables -- occasionally the
  1054     system indicates accidental variables via the error "rhs contains
  1055     extra variables".
  1056 
  1057     Type classes and type constructors are marked according to their
  1058     concrete syntax.  Some old translations rules need to be written
  1059     for the "type" category, using type constructor application
  1060     instead of pseudo-term application of the default category
  1061     "logic".
  1062 
  1063   - 'parse_translation' etc. in ML may use the following
  1064     antiquotations:
  1065 
  1066       @{class_syntax c}   -- type class c within parse tree / AST
  1067       @{term_syntax c}    -- type constructor c within parse tree / AST
  1068       @{const_syntax c}   -- ML version of "CONST c" above
  1069       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
  1070 
  1071   - Literal types within 'typed_print_translations', i.e. those *not*
  1072     represented as pseudo-terms are represented verbatim.  Use @{class
  1073     c} or @{type_name c} here instead of the above syntax
  1074     antiquotations.
  1075 
  1076 Note that old non-authentic syntax was based on unqualified base
  1077 names, so all of the above "constant" names would coincide.  Recall
  1078 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
  1079 diagnose syntax problems.
  1080 
  1081 * Type constructors admit general mixfix syntax, not just infix.
  1082 
  1083 * Concrete syntax may be attached to local entities without a proof
  1084 body, too.  This works via regular mixfix annotations for 'fix',
  1085 'def', 'obtain' etc. or via the explicit 'write' command, which is
  1086 similar to the 'notation' command in theory specifications.
  1087 
  1088 * Discontinued unnamed infix syntax (legacy feature for many years) --
  1089 need to specify constant name and syntax separately.  Internal ML
  1090 datatype constructors have been renamed from InfixName to Infix etc.
  1091 Minor INCOMPATIBILITY.
  1092 
  1093 * Schematic theorem statements need to be explicitly markup as such,
  1094 via commands 'schematic_lemma', 'schematic_theorem',
  1095 'schematic_corollary'.  Thus the relevance of the proof is made
  1096 syntactically clear, which impacts performance in a parallel or
  1097 asynchronous interactive environment.  Minor INCOMPATIBILITY.
  1098 
  1099 * Use of cumulative prems via "!" in some proof methods has been
  1100 discontinued (old legacy feature).
  1101 
  1102 * References 'trace_simp' and 'debug_simp' have been replaced by
  1103 configuration options stored in the context. Enabling tracing (the
  1104 case of debugging is similar) in proofs works via
  1105 
  1106   using [[trace_simp = true]]
  1107 
  1108 Tracing is then active for all invocations of the simplifier in
  1109 subsequent goal refinement steps. Tracing may also still be enabled or
  1110 disabled via the ProofGeneral settings menu.
  1111 
  1112 * Separate commands 'hide_class', 'hide_type', 'hide_const',
  1113 'hide_fact' replace the former 'hide' KIND command.  Minor
  1114 INCOMPATIBILITY.
  1115 
  1116 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
  1117 more efficient than combinations with -q1 or -q2.
  1118 
  1119 
  1120 *** Pure ***
  1121 
  1122 * Proofterms record type-class reasoning explicitly, using the
  1123 "unconstrain" operation internally.  This eliminates all sort
  1124 constraints from a theorem and proof, introducing explicit
  1125 OFCLASS-premises.  On the proof term level, this operation is
  1126 automatically applied at theorem boundaries, such that closed proofs
  1127 are always free of sort constraints.  INCOMPATIBILITY for tools that
  1128 inspect proof terms.
  1129 
  1130 * Local theory specifications may depend on extra type variables that
  1131 are not present in the result type -- arguments TYPE('a) :: 'a itself
  1132 are added internally.  For example:
  1133 
  1134   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
  1135 
  1136 * Predicates of locales introduced by classes carry a mandatory
  1137 "class" prefix.  INCOMPATIBILITY.
  1138 
  1139 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
  1140 
  1141 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
  1142 'class' instead.
  1143 
  1144 * Command 'code_reflect' allows to incorporate generated ML code into
  1145 runtime environment; replaces immature code_datatype antiquotation.
  1146 INCOMPATIBILITY.
  1147 
  1148 * Code generator: simple concept for abstract datatypes obeying
  1149 invariants.
  1150 
  1151 * Code generator: details of internal data cache have no impact on the
  1152 user space functionality any longer.
  1153 
  1154 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  1155 subgoals.  This is more appropriate for interpretations with 'where'.
  1156 INCOMPATIBILITY.
  1157 
  1158 * Command 'example_proof' opens an empty proof body.  This allows to
  1159 experiment with Isar, without producing any persistent result.
  1160 
  1161 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  1162 within a local theory context, with explicit checking of the
  1163 constructors involved (in contrast to the raw 'syntax' versions).
  1164 
  1165 * Commands 'types' and 'typedecl' now work within a local theory
  1166 context -- without introducing dependencies on parameters or
  1167 assumptions, which is not possible in Isabelle/Pure.
  1168 
  1169 * Command 'defaultsort' has been renamed to 'default_sort', it works
  1170 within a local theory context.  Minor INCOMPATIBILITY.
  1171 
  1172 
  1173 *** HOL ***
  1174 
  1175 * Command 'typedef' now works within a local theory context -- without
  1176 introducing dependencies on parameters or assumptions, which is not
  1177 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  1178 contain multiple interpretations of local typedefs (with different
  1179 non-emptiness proofs), even in a global theory context.
  1180 
  1181 * New package for quotient types.  Commands 'quotient_type' and
  1182 'quotient_definition' may be used for defining types and constants by
  1183 quotient constructions.  An example is the type of integers created by
  1184 quotienting pairs of natural numbers:
  1185 
  1186   fun
  1187     intrel :: "(nat * nat) => (nat * nat) => bool"
  1188   where
  1189     "intrel (x, y) (u, v) = (x + v = u + y)"
  1190 
  1191   quotient_type int = "nat * nat" / intrel
  1192     by (auto simp add: equivp_def expand_fun_eq)
  1193 
  1194   quotient_definition
  1195     "0::int" is "(0::nat, 0::nat)"
  1196 
  1197 The method "lifting" can be used to lift of theorems from the
  1198 underlying "raw" type to the quotient type.  The example
  1199 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  1200 construction and provides a reasoning infrastructure for finite sets.
  1201 
  1202 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  1203 clash with new theory Quotient in Main HOL.
  1204 
  1205 * Moved the SMT binding into the main HOL session, eliminating
  1206 separate HOL-SMT session.
  1207 
  1208 * List membership infix mem operation is only an input abbreviation.
  1209 INCOMPATIBILITY.
  1210 
  1211 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  1212 for future developements; former Library/Word.thy is still present in
  1213 the AFP entry RSAPPS.
  1214 
  1215 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  1216 longer shadowed.  INCOMPATIBILITY.
  1217 
  1218 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  1219 INCOMPATIBILITY.
  1220 
  1221 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  1222 INCOMPATIBILITY.
  1223 
  1224 * Dropped normalizing_semiring etc; use the facts in semiring classes
  1225 instead.  INCOMPATIBILITY.
  1226 
  1227 * Dropped several real-specific versions of lemmas about floor and
  1228 ceiling; use the generic lemmas from theory "Archimedean_Field"
  1229 instead.  INCOMPATIBILITY.
  1230 
  1231   floor_number_of_eq         ~> floor_number_of
  1232   le_floor_eq_number_of      ~> number_of_le_floor
  1233   le_floor_eq_zero           ~> zero_le_floor
  1234   le_floor_eq_one            ~> one_le_floor
  1235   floor_less_eq_number_of    ~> floor_less_number_of
  1236   floor_less_eq_zero         ~> floor_less_zero
  1237   floor_less_eq_one          ~> floor_less_one
  1238   less_floor_eq_number_of    ~> number_of_less_floor
  1239   less_floor_eq_zero         ~> zero_less_floor
  1240   less_floor_eq_one          ~> one_less_floor
  1241   floor_le_eq_number_of      ~> floor_le_number_of
  1242   floor_le_eq_zero           ~> floor_le_zero
  1243   floor_le_eq_one            ~> floor_le_one
  1244   floor_subtract_number_of   ~> floor_diff_number_of
  1245   floor_subtract_one         ~> floor_diff_one
  1246   ceiling_number_of_eq       ~> ceiling_number_of
  1247   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  1248   ceiling_le_zero_eq         ~> ceiling_le_zero
  1249   ceiling_le_eq_one          ~> ceiling_le_one
  1250   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  1251   less_ceiling_eq_zero       ~> zero_less_ceiling
  1252   less_ceiling_eq_one        ~> one_less_ceiling
  1253   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  1254   ceiling_less_eq_zero       ~> ceiling_less_zero
  1255   ceiling_less_eq_one        ~> ceiling_less_one
  1256   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  1257   le_ceiling_eq_zero         ~> zero_le_ceiling
  1258   le_ceiling_eq_one          ~> one_le_ceiling
  1259   ceiling_subtract_number_of ~> ceiling_diff_number_of
  1260   ceiling_subtract_one       ~> ceiling_diff_one
  1261 
  1262 * Theory "Finite_Set": various folding_XXX locales facilitate the
  1263 application of the various fold combinators on finite sets.
  1264 
  1265 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  1266 provides abstract red-black tree type which is backed by "RBT_Impl" as
  1267 implementation.  INCOMPATIBILTY.
  1268 
  1269 * Theory Library/Coinductive_List has been removed -- superseded by
  1270 AFP/thys/Coinductive.
  1271 
  1272 * Theory PReal, including the type "preal" and related operations, has
  1273 been removed.  INCOMPATIBILITY.
  1274 
  1275 * Real: new development using Cauchy Sequences.
  1276 
  1277 * Split off theory "Big_Operators" containing setsum, setprod,
  1278 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  1279 
  1280 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  1281 "Int" etc.  INCOMPATIBILITY.
  1282 
  1283 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  1284 
  1285 * New set of rules "ac_simps" provides combined assoc / commute
  1286 rewrites for all interpretations of the appropriate generic locales.
  1287 
  1288 * Renamed theory "OrderedGroup" to "Groups" and split theory
  1289 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  1290 appropriate and more consistent names suitable for name prefixes
  1291 within the HOL theories.  INCOMPATIBILITY.
  1292 
  1293 * Some generic constants have been put to appropriate theories:
  1294   - less_eq, less: Orderings
  1295   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  1296   - inverse, divide: Rings
  1297 INCOMPATIBILITY.
  1298 
  1299 * More consistent naming of type classes involving orderings (and
  1300 lattices):
  1301 
  1302     lower_semilattice                   ~> semilattice_inf
  1303     upper_semilattice                   ~> semilattice_sup
  1304 
  1305     dense_linear_order                  ~> dense_linorder
  1306 
  1307     pordered_ab_group_add               ~> ordered_ab_group_add
  1308     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  1309     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  1310     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  1311     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  1312     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  1313     pordered_cancel_semiring            ~> ordered_cancel_semiring
  1314     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  1315     pordered_comm_ring                  ~> ordered_comm_ring
  1316     pordered_comm_semiring              ~> ordered_comm_semiring
  1317     pordered_ring                       ~> ordered_ring
  1318     pordered_ring_abs                   ~> ordered_ring_abs
  1319     pordered_semiring                   ~> ordered_semiring
  1320 
  1321     ordered_ab_group_add                ~> linordered_ab_group_add
  1322     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  1323     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  1324     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  1325     ordered_field                       ~> linordered_field
  1326     ordered_field_no_lb                 ~> linordered_field_no_lb
  1327     ordered_field_no_ub                 ~> linordered_field_no_ub
  1328     ordered_field_dense_linear_order    ~> dense_linordered_field
  1329     ordered_idom                        ~> linordered_idom
  1330     ordered_ring                        ~> linordered_ring
  1331     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  1332     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  1333     ordered_ring_strict                 ~> linordered_ring_strict
  1334     ordered_semidom                     ~> linordered_semidom
  1335     ordered_semiring                    ~> linordered_semiring
  1336     ordered_semiring_1                  ~> linordered_semiring_1
  1337     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  1338     ordered_semiring_strict             ~> linordered_semiring_strict
  1339 
  1340   The following slightly odd type classes have been moved to a
  1341   separate theory Library/Lattice_Algebras:
  1342 
  1343     lordered_ab_group_add               ~> lattice_ab_group_add
  1344     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  1345     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  1346     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  1347     lordered_ring                       ~> lattice_ring
  1348 
  1349 INCOMPATIBILITY.
  1350 
  1351 * Refined field classes:
  1352   - classes division_ring_inverse_zero, field_inverse_zero,
  1353     linordered_field_inverse_zero include rule inverse 0 = 0 --
  1354     subsumes former division_by_zero class;
  1355   - numerous lemmas have been ported from field to division_ring.
  1356 INCOMPATIBILITY.
  1357 
  1358 * Refined algebra theorem collections:
  1359   - dropped theorem group group_simps, use algebra_simps instead;
  1360   - dropped theorem group ring_simps, use field_simps instead;
  1361   - proper theorem collection field_simps subsumes former theorem
  1362     groups field_eq_simps and field_simps;
  1363   - dropped lemma eq_minus_self_iff which is a duplicate for
  1364     equal_neg_zero.
  1365 INCOMPATIBILITY.
  1366 
  1367 * Theory Finite_Set and List: some lemmas have been generalized from
  1368 sets to lattices:
  1369 
  1370   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  1371   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  1372   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  1373   union_Union_fold_union        ~> sup_Sup_fold_sup
  1374   Inter_fold_inter              ~> Inf_fold_inf
  1375   Union_fold_union              ~> Sup_fold_sup
  1376   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  1377   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  1378   INTER_fold_inter              ~> INFI_fold_inf
  1379   UNION_fold_union              ~> SUPR_fold_sup
  1380 
  1381 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  1382 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  1383 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  1384 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  1385 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  1386 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  1387 
  1388 * Reorganized theory Multiset: swapped notation of pointwise and
  1389 multiset order:
  1390 
  1391   - pointwise ordering is instance of class order with standard syntax
  1392     <= and <;
  1393   - multiset ordering has syntax <=# and <#; partial order properties
  1394     are provided by means of interpretation with prefix
  1395     multiset_order;
  1396   - less duplication, less historical organization of sections,
  1397     conversion from associations lists to multisets, rudimentary code
  1398     generation;
  1399   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  1400     if needed.
  1401 
  1402 Renamed:
  1403 
  1404   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  1405   multi_count_ext  ~>  multiset_ext
  1406   diff_union_inverse2  ~>  diff_union_cancelR
  1407 
  1408 INCOMPATIBILITY.
  1409 
  1410 * Theory Permutation: replaced local "remove" by List.remove1.
  1411 
  1412 * Code generation: ML and OCaml code is decorated with signatures.
  1413 
  1414 * Theory List: added transpose.
  1415 
  1416 * Library/Nat_Bijection.thy is a collection of bijective functions
  1417 between nat and other types, which supersedes the older libraries
  1418 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  1419 
  1420   Constants:
  1421   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  1422   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  1423   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  1424   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  1425   Countable.pair_encode           ~> prod_encode
  1426   NatIso.prod2nat                 ~> prod_encode
  1427   NatIso.nat2prod                 ~> prod_decode
  1428   NatIso.sum2nat                  ~> sum_encode
  1429   NatIso.nat2sum                  ~> sum_decode
  1430   NatIso.list2nat                 ~> list_encode
  1431   NatIso.nat2list                 ~> list_decode
  1432   NatIso.set2nat                  ~> set_encode
  1433   NatIso.nat2set                  ~> set_decode
  1434 
  1435   Lemmas:
  1436   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  1437   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  1438   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  1439   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  1440   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  1441   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  1442   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  1443   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  1444   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  1445   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  1446   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  1447   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  1448   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  1449 
  1450 * Sledgehammer:
  1451   - Renamed ATP commands:
  1452     atp_info     ~> sledgehammer running_atps
  1453     atp_kill     ~> sledgehammer kill_atps
  1454     atp_messages ~> sledgehammer messages
  1455     atp_minimize ~> sledgehammer minimize
  1456     print_atps   ~> sledgehammer available_atps
  1457     INCOMPATIBILITY.
  1458   - Added user's manual ("isabelle doc sledgehammer").
  1459   - Added option syntax and "sledgehammer_params" to customize
  1460     Sledgehammer's behavior.  See the manual for details.
  1461   - Modified the Isar proof reconstruction code so that it produces
  1462     direct proofs rather than proofs by contradiction.  (This feature
  1463     is still experimental.)
  1464   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  1465     full-typed mode.
  1466   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  1467 
  1468 * Nitpick:
  1469   - Added and implemented "binary_ints" and "bits" options.
  1470   - Added "std" option and implemented support for nonstandard models.
  1471   - Added and implemented "finitize" option to improve the precision
  1472     of infinite datatypes based on a monotonicity analysis.
  1473   - Added support for quotient types.
  1474   - Added support for "specification" and "ax_specification"
  1475     constructs.
  1476   - Added support for local definitions (for "function" and
  1477     "termination" proofs).
  1478   - Added support for term postprocessors.
  1479   - Optimized "Multiset.multiset" and "FinFun.finfun".
  1480   - Improved efficiency of "destroy_constrs" optimization.
  1481   - Fixed soundness bugs related to "destroy_constrs" optimization and
  1482     record getters.
  1483   - Fixed soundness bug related to higher-order constructors.
  1484   - Fixed soundness bug when "full_descrs" is enabled.
  1485   - Improved precision of set constructs.
  1486   - Added "atoms" option.
  1487   - Added cache to speed up repeated Kodkod invocations on the same
  1488     problems.
  1489   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  1490     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  1491     "SAT4J_Light".  INCOMPATIBILITY.
  1492   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  1493     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  1494   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  1495 
  1496 * Method "induct" now takes instantiations of the form t, where t is not
  1497   a variable, as a shorthand for "x == t", where x is a fresh variable.
  1498   If this is not intended, t has to be enclosed in parentheses.
  1499   By default, the equalities generated by definitional instantiations
  1500   are pre-simplified, which may cause parameters of inductive cases
  1501   to disappear, or may even delete some of the inductive cases.
  1502   Use "induct (no_simp)" instead of "induct" to restore the old
  1503   behaviour. The (no_simp) option is also understood by the "cases"
  1504   and "nominal_induct" methods, which now perform pre-simplification, too.
  1505   INCOMPATIBILITY.
  1506 
  1507 
  1508 *** HOLCF ***
  1509 
  1510 * Variable names in lemmas generated by the domain package have
  1511 changed; the naming scheme is now consistent with the HOL datatype
  1512 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  1513 
  1514 * The domain package no longer defines the function "foo_copy" for
  1515 recursive domain "foo".  The reach lemma is now stated directly in
  1516 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  1517 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  1518 
  1519 * Most definedness lemmas generated by the domain package (previously
  1520 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  1521 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  1522 Proofs that used definedness lemmas as intro rules may break,
  1523 potential INCOMPATIBILITY.
  1524 
  1525 * Induction and casedist rules generated by the domain package now
  1526 declare proper case_names (one called "bottom", and one named for each
  1527 constructor).  INCOMPATIBILITY.
  1528 
  1529 * For mutually-recursive domains, separate "reach" and "take_lemma"
  1530 rules are generated for each domain, INCOMPATIBILITY.
  1531 
  1532   foo_bar.reach       ~> foo.reach  bar.reach
  1533   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  1534 
  1535 * Some lemmas generated by the domain package have been renamed for
  1536 consistency with the datatype package, INCOMPATIBILITY.
  1537 
  1538   foo.ind        ~> foo.induct
  1539   foo.finite_ind ~> foo.finite_induct
  1540   foo.coind      ~> foo.coinduct
  1541   foo.casedist   ~> foo.exhaust
  1542   foo.exhaust    ~> foo.nchotomy
  1543 
  1544 * For consistency with other definition packages, the fixrec package
  1545 now generates qualified theorem names, INCOMPATIBILITY.
  1546 
  1547   foo_simps  ~> foo.simps
  1548   foo_unfold ~> foo.unfold
  1549   foo_induct ~> foo.induct
  1550 
  1551 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  1552 method and internal fixrec proofs now use the default simpset instead.
  1553 INCOMPATIBILITY.
  1554 
  1555 * The "contlub" predicate has been removed.  Proof scripts should use
  1556 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  1557 
  1558 * The "admw" predicate has been removed, INCOMPATIBILITY.
  1559 
  1560 * The constants cpair, cfst, and csnd have been removed in favor of
  1561 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  1562 
  1563 
  1564 *** ML ***
  1565 
  1566 * Antiquotations for basic formal entities:
  1567 
  1568     @{class NAME}         -- type class
  1569     @{class_syntax NAME}  -- syntax representation of the above
  1570 
  1571     @{type_name NAME}     -- logical type
  1572     @{type_abbrev NAME}   -- type abbreviation
  1573     @{nonterminal NAME}   -- type of concrete syntactic category
  1574     @{type_syntax NAME}   -- syntax representation of any of the above
  1575 
  1576     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  1577     @{const_abbrev NAME}  -- abbreviated constant
  1578     @{const_syntax NAME}  -- syntax representation of any of the above
  1579 
  1580 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  1581 syntax constant (cf. 'syntax' command).
  1582 
  1583 * Antiquotation @{make_string} inlines a function to print arbitrary
  1584 values similar to the ML toplevel.  The result is compiler dependent
  1585 and may fall back on "?" in certain situations.
  1586 
  1587 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  1588 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  1589 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  1590 not work with the asynchronous Isar document model.
  1591 
  1592 * Configuration options now admit dynamic default values, depending on
  1593 the context or even global references.
  1594 
  1595 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  1596 uses an efficient external library if available (for Poly/ML).
  1597 
  1598 * Renamed some important ML structures, while keeping the old names
  1599 for some time as aliases within the structure Legacy:
  1600 
  1601   OuterKeyword  ~>  Keyword
  1602   OuterLex      ~>  Token
  1603   OuterParse    ~>  Parse
  1604   OuterSyntax   ~>  Outer_Syntax
  1605   PrintMode     ~>  Print_Mode
  1606   SpecParse     ~>  Parse_Spec
  1607   ThyInfo       ~>  Thy_Info
  1608   ThyLoad       ~>  Thy_Load
  1609   ThyOutput     ~>  Thy_Output
  1610   TypeInfer     ~>  Type_Infer
  1611 
  1612 Note that "open Legacy" simplifies porting of sources, but forgetting
  1613 to remove it again will complicate porting again in the future.
  1614 
  1615 * Most operations that refer to a global context are named
  1616 accordingly, e.g. Simplifier.global_context or
  1617 ProofContext.init_global.  There are some situations where a global
  1618 context actually works, but under normal circumstances one needs to
  1619 pass the proper local context through the code!
  1620 
  1621 * Discontinued old TheoryDataFun with its copy/init operation -- data
  1622 needs to be pure.  Functor Theory_Data_PP retains the traditional
  1623 Pretty.pp argument to merge, which is absent in the standard
  1624 Theory_Data version.
  1625 
  1626 * Sorts.certify_sort and derived "cert" operations for types and terms
  1627 no longer minimize sorts.  Thus certification at the boundary of the
  1628 inference kernel becomes invariant under addition of class relations,
  1629 which is an important monotonicity principle.  Sorts are now minimized
  1630 in the syntax layer only, at the boundary between the end-user and the
  1631 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  1632 explicitly in rare situations.
  1633 
  1634 * Renamed old-style Drule.standard to Drule.export_without_context, to
  1635 emphasize that this is in no way a standard operation.
  1636 INCOMPATIBILITY.
  1637 
  1638 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  1639 usual for resolution.  Rare INCOMPATIBILITY.
  1640 
  1641 * Renamed varify/unvarify operations to varify_global/unvarify_global
  1642 to emphasize that these only work in a global situation (which is
  1643 quite rare).
  1644 
  1645 * Curried take and drop in library.ML; negative length is interpreted
  1646 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  1647 
  1648 * Proof terms: type substitutions on proof constants now use canonical
  1649 order of type variables.  INCOMPATIBILITY for tools working with proof
  1650 terms.
  1651 
  1652 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  1653 may no longer carry premises.  User-level specifications are
  1654 transformed accordingly by Thm.add_axiom/add_def.
  1655 
  1656 
  1657 *** System ***
  1658 
  1659 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  1660 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  1661 proof terms are enabled unconditionally in the new HOL-Proofs image.
  1662 
  1663 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  1664 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  1665 respectively.
  1666 
  1667 * Old lib/scripts/polyml-platform is superseded by the
  1668 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  1669 variant, even on a 64 bit machine.  The following example setting
  1670 prefers 64 bit if available:
  1671 
  1672   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  1673 
  1674 * The preliminary Isabelle/jEdit application demonstrates the emerging
  1675 Isabelle/Scala layer for advanced prover interaction and integration.
  1676 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  1677 component.
  1678 
  1679 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  1680 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  1681 similar to the default assignment of the document preparation system
  1682 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  1683 provides some operations for direct access to the font without asking
  1684 the user for manual installation.
  1685 
  1686 
  1687 
  1688 New in Isabelle2009-1 (December 2009)
  1689 -------------------------------------
  1690 
  1691 *** General ***
  1692 
  1693 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  1694 one backslash should be used, even in ML sources.
  1695 
  1696 
  1697 *** Pure ***
  1698 
  1699 * Locale interpretation propagates mixins along the locale hierarchy.
  1700 The currently only available mixins are the equations used to map
  1701 local definitions to terms of the target domain of an interpretation.
  1702 
  1703 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  1704 loc" to print all interpretations of locale "loc" in the theory.
  1705 Interpretations in proofs are not shown.
  1706 
  1707 * Thoroughly revised locales tutorial.  New section on conditional
  1708 interpretation.
  1709 
  1710 * On instantiation of classes, remaining undefined class parameters
  1711 are formally declared.  INCOMPATIBILITY.
  1712 
  1713 
  1714 *** Document preparation ***
  1715 
  1716 * New generalized style concept for printing terms: @{foo (style) ...}
  1717 instead of @{foo_style style ...}  (old form is still retained for
  1718 backward compatibility).  Styles can be also applied for
  1719 antiquotations prop, term_type and typeof.
  1720 
  1721 
  1722 *** HOL ***
  1723 
  1724 * New proof method "smt" for a combination of first-order logic with
  1725 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  1726 fixed-size bitvectors; there is also basic support for higher-order
  1727 features (esp. lambda abstractions).  It is an incomplete decision
  1728 procedure based on external SMT solvers using the oracle mechanism;
  1729 for the SMT solver Z3, this method is proof-producing.  Certificates
  1730 are provided to avoid calling the external solvers solely for
  1731 re-checking proofs.  Due to a remote SMT service there is no need for
  1732 installing SMT solvers locally.  See src/HOL/SMT.
  1733 
  1734 * New commands to load and prove verification conditions generated by
  1735 the Boogie program verifier or derived systems (e.g. the Verifying C
  1736 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1737 
  1738 * New counterexample generator tool 'nitpick' based on the Kodkod
  1739 relational model finder.  See src/HOL/Tools/Nitpick and
  1740 src/HOL/Nitpick_Examples.
  1741 
  1742 * New commands 'code_pred' and 'values' to invoke the predicate
  1743 compiler and to enumerate values of inductive predicates.
  1744 
  1745 * A tabled implementation of the reflexive transitive closure.
  1746 
  1747 * New implementation of quickcheck uses generic code generator;
  1748 default generators are provided for all suitable HOL types, records
  1749 and datatypes.  Old quickcheck can be re-activated importing theory
  1750 Library/SML_Quickcheck.
  1751 
  1752 * New testing tool Mirabelle for automated proof tools.  Applies
  1753 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1754 every proof step in a theory.  To be used in batch mode via the
  1755 "mirabelle" utility.
  1756 
  1757 * New proof method "sos" (sum of squares) for nonlinear real
  1758 arithmetic (originally due to John Harison). It requires theory
  1759 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1760 works well in practice on quantifier-free real arithmetic with +, -,
  1761 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1762 inequalities between polynomials.  It makes use of external
  1763 semidefinite programming solvers.  Method "sos" generates a
  1764 certificate that can be pasted into the proof thus avoiding the need
  1765 to call an external tool every time the proof is checked.  See
  1766 src/HOL/Library/Sum_Of_Squares.
  1767 
  1768 * New method "linarith" invokes existing linear arithmetic decision
  1769 procedure only.
  1770 
  1771 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1772 
  1773 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1774 Causes full type information to be output to the ATPs.  This slows
  1775 ATPs down considerably but eliminates a source of unsound "proofs"
  1776 that fail later.
  1777 
  1778 * New method "metisFT": A version of metis that uses full type
  1779 information in order to avoid failures of proof reconstruction.
  1780 
  1781 * New evaluator "approximate" approximates an real valued term using
  1782 the same method as the approximation method.
  1783 
  1784 * Method "approximate" now supports arithmetic expressions as
  1785 boundaries of intervals and implements interval splitting and Taylor
  1786 series expansion.
  1787 
  1788 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1789 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1790 
  1791 * New theory SupInf of the supremum and infimum operators for sets of
  1792 reals.
  1793 
  1794 * New theory Probability, which contains a development of measure
  1795 theory, eventually leading to Lebesgue integration and probability.
  1796 
  1797 * Extended Multivariate Analysis to include derivation and Brouwer's
  1798 fixpoint theorem.
  1799 
  1800 * Reorganization of number theory, INCOMPATIBILITY:
  1801   - new number theory development for nat and int, in theories Divides
  1802     and GCD as well as in new session Number_Theory
  1803   - some constants and facts now suffixed with _nat and _int
  1804     accordingly
  1805   - former session NumberTheory now named Old_Number_Theory, including
  1806     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1807   - moved theory Pocklington from src/HOL/Library to
  1808     src/HOL/Old_Number_Theory
  1809 
  1810 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1811 lcm of finite and infinite sets. It is shown that they form a complete
  1812 lattice.
  1813 
  1814 * Class semiring_div requires superclass no_zero_divisors and proof of
  1815 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1816 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1817 generalized to class semiring_div, subsuming former theorems
  1818 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1819 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1820 INCOMPATIBILITY.
  1821 
  1822 * Refinements to lattice classes and sets:
  1823   - less default intro/elim rules in locale variant, more default
  1824     intro/elim rules in class variant: more uniformity
  1825   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1826     le_inf_iff
  1827   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1828     sup_aci)
  1829   - renamed ACI to inf_sup_aci
  1830   - new class "boolean_algebra"
  1831   - class "complete_lattice" moved to separate theory
  1832     "Complete_Lattice"; corresponding constants (and abbreviations)
  1833     renamed and with authentic syntax:
  1834     Set.Inf ~>    Complete_Lattice.Inf
  1835     Set.Sup ~>    Complete_Lattice.Sup
  1836     Set.INFI ~>   Complete_Lattice.INFI
  1837     Set.SUPR ~>   Complete_Lattice.SUPR
  1838     Set.Inter ~>  Complete_Lattice.Inter
  1839     Set.Union ~>  Complete_Lattice.Union
  1840     Set.INTER ~>  Complete_Lattice.INTER
  1841     Set.UNION ~>  Complete_Lattice.UNION
  1842   - authentic syntax for
  1843     Set.Pow
  1844     Set.image
  1845   - mere abbreviations:
  1846     Set.empty               (for bot)
  1847     Set.UNIV                (for top)
  1848     Set.inter               (for inf, formerly Set.Int)
  1849     Set.union               (for sup, formerly Set.Un)
  1850     Complete_Lattice.Inter  (for Inf)
  1851     Complete_Lattice.Union  (for Sup)
  1852     Complete_Lattice.INTER  (for INFI)
  1853     Complete_Lattice.UNION  (for SUPR)
  1854   - object-logic definitions as far as appropriate
  1855 
  1856 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1857 Un_subset_iff are explicitly deleted as default simp rules; then also
  1858 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1859 deleted to achieve the desired effect.
  1860 
  1861 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1862 rules by default any longer; the same applies to min_max.inf_absorb1
  1863 etc.  INCOMPATIBILITY.
  1864 
  1865 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1866 pred_set_conv by default.  INCOMPATIBILITY.
  1867 
  1868 * Power operations on relations and functions are now one dedicated
  1869 constant "compow" with infix syntax "^^".  Power operation on
  1870 multiplicative monoids retains syntax "^" and is now defined generic
  1871 in class power.  INCOMPATIBILITY.
  1872 
  1873 * Relation composition "R O S" now has a more standard argument order:
  1874 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1875 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1876 break, since the O_assoc rule was not rewritten like this.  Fix using
  1877 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1878 
  1879 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1880 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1881 INCOMPATIBILITY.
  1882 
  1883 * Most rules produced by inductive and datatype package have mandatory
  1884 prefixes.  INCOMPATIBILITY.
  1885 
  1886 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1887 the attribute of the same name.  Each of the theorems in the list
  1888 DERIV_intros assumes composition with an additional function and
  1889 matches a variable to the derivative, which has to be solved by the
  1890 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1891 of most elementary terms.  Former Maclauren.DERIV_tac and
  1892 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1893 INCOMPATIBILITY.
  1894 
  1895 * Code generator attributes follow the usual underscore convention:
  1896     code_unfold     replaces    code unfold
  1897     code_post       replaces    code post
  1898     etc.
  1899   INCOMPATIBILITY.
  1900 
  1901 * Renamed methods:
  1902     sizechange -> size_change
  1903     induct_scheme -> induction_schema
  1904   INCOMPATIBILITY.
  1905 
  1906 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1907 INCOMPATIBILITY, use "undefined" directly.
  1908 
  1909 * Renamed theorems:
  1910     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1911     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1912     Suc_plus1 -> Suc_eq_plus1
  1913     *anti_sym -> *antisym*
  1914     vector_less_eq_def -> vector_le_def
  1915   INCOMPATIBILITY.
  1916 
  1917 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1918 INCOMPATIBILITY.
  1919 
  1920 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1921 INCOMPATIBILITY.
  1922 
  1923 
  1924 *** HOLCF ***
  1925 
  1926 * Theory Representable defines a class "rep" of domains that are
  1927 representable (via an ep-pair) in the universal domain type "udom".
  1928 Instances are provided for all type constructors defined in HOLCF.
  1929 
  1930 * The 'new_domain' command is a purely definitional version of the
  1931 domain package, for representable domains.  Syntax is identical to the
  1932 old domain package.  The 'new_domain' package also supports indirect
  1933 recursion using previously-defined type constructors.  See
  1934 src/HOLCF/ex/New_Domain.thy for examples.
  1935 
  1936 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1937 on the left-hand side of an equation, and then performs
  1938 simplification.  Rewriting is done using rules declared with the
  1939 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1940 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1941 
  1942 * The pattern-match compiler in 'fixrec' can now handle constructors
  1943 with HOL function types.  Pattern-match combinators for the Pair
  1944 constructor are pre-configured.
  1945 
  1946 * The 'fixrec' package now produces better fixed-point induction rules
  1947 for mutually-recursive definitions:  Induction rules have conclusions
  1948 of the form "P foo bar" instead of "P <foo, bar>".
  1949 
  1950 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1951 been renamed to "below".  The name "below" now replaces "less" in many
  1952 theorem names.  (Legacy theorem names using "less" are still supported
  1953 as well.)
  1954 
  1955 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1956 patterns can be used to generate strictness rules, or to make
  1957 functions more strict (much like the bang-patterns supported by the
  1958 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1959 examples.
  1960 
  1961 
  1962 *** ML ***
  1963 
  1964 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1965 errors and run-time exceptions, including detailed source positions.
  1966 
  1967 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1968 identified entries, with some additional information such as source
  1969 position, logical grouping etc.
  1970 
  1971 * Theory and context data is now introduced by the simplified and
  1972 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1973 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1974 copy operation) is still available for some time.
  1975 
  1976 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1977 provides a high-level programming interface to synchronized state
  1978 variables with atomic update.  This works via pure function
  1979 application within a critical section -- its runtime should be as
  1980 short as possible; beware of deadlocks if critical code is nested,
  1981 either directly or indirectly via other synchronized variables!
  1982 
  1983 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1984 wraps raw ML references, explicitly indicating their non-thread-safe
  1985 behaviour.  The Isar toplevel keeps this structure open, to
  1986 accommodate Proof General as well as quick and dirty interactive
  1987 experiments with references.
  1988 
  1989 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1990 parallel tactical reasoning.
  1991 
  1992 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1993 are similar to SUBPROOF, but are slightly more flexible: only the
  1994 specified parts of the subgoal are imported into the context, and the
  1995 body tactic may introduce new subgoals and schematic variables.
  1996 
  1997 * Old tactical METAHYPS, which does not observe the proof context, has
  1998 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1999 or Subgoal.FOCUS etc.
  2000 
  2001 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  2002 functors have their own ML name space there is no point to mark them
  2003 separately.)  Minor INCOMPATIBILITY.
  2004 
  2005 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  2006 
  2007 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  2008 INCOMPATIBILITY.
  2009 
  2010 * Operations of structure Skip_Proof no longer require quick_and_dirty
  2011 mode, which avoids critical setmp.
  2012 
  2013 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  2014 combinators for "args".  INCOMPATIBILITY, need to use simplified
  2015 Attrib/Method.setup introduced in Isabelle2009.
  2016 
  2017 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  2018 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  2019 last resort.  INCOMPATIBILITY.
  2020 
  2021 * Display.pretty_thm now requires a proper context (cf. former
  2022 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  2023 or even Display.pretty_thm_without_context as last resort.
  2024 INCOMPATIBILITY.
  2025 
  2026 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  2027 Syntax.pretty_typ/term directly, preferably with proper context
  2028 instead of global theory.
  2029 
  2030 
  2031 *** System ***
  2032 
  2033 * Further fine tuning of parallel proof checking, scales up to 8 cores
  2034 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  2035 usedir option -q.
  2036 
  2037 * Support for additional "Isabelle components" via etc/components, see
  2038 also the system manual.
  2039 
  2040 * The isabelle makeall tool now operates on all components with
  2041 IsaMakefile, not just hardwired "logics".
  2042 
  2043 * Removed "compress" option from isabelle-process and isabelle usedir;
  2044 this is always enabled.
  2045 
  2046 * Discontinued support for Poly/ML 4.x versions.
  2047 
  2048 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  2049 on a given logic image.  This requires the lighttpd webserver and is
  2050 currently supported on Linux only.
  2051 
  2052 
  2053 
  2054 New in Isabelle2009 (April 2009)
  2055 --------------------------------
  2056 
  2057 *** General ***
  2058 
  2059 * Simplified main Isabelle executables, with less surprises on
  2060 case-insensitive file-systems (such as Mac OS).
  2061 
  2062   - The main Isabelle tool wrapper is now called "isabelle" instead of
  2063     "isatool."
  2064 
  2065   - The former "isabelle" alias for "isabelle-process" has been
  2066     removed (should rarely occur to regular users).
  2067 
  2068   - The former "isabelle-interface" and its alias "Isabelle" have been
  2069     removed (interfaces are now regular Isabelle tools).
  2070 
  2071 Within scripts and make files, the Isabelle environment variables
  2072 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  2073 respectively.  (The latter are still available as legacy feature.)
  2074 
  2075 The old isabelle-interface wrapper could react in confusing ways if
  2076 the interface was uninstalled or changed otherwise.  Individual
  2077 interface tool configuration is now more explicit, see also the
  2078 Isabelle system manual.  In particular, Proof General is now available
  2079 via "isabelle emacs".
  2080 
  2081 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  2082 purge installed copies of Isabelle executables and re-run "isabelle
  2083 install -p ...", or use symlinks.
  2084 
  2085 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  2086 old ~/isabelle, which was slightly non-standard and apt to cause
  2087 surprises on case-insensitive file-systems (such as Mac OS).
  2088 
  2089 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  2090 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  2091 care is required when using older releases of Isabelle.  Note that
  2092 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  2093 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  2094 
  2095 * Proofs of fully specified statements are run in parallel on
  2096 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  2097 a regular 4-core machine, if the initial heap space is made reasonably
  2098 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  2099 
  2100 * The main reference manuals ("isar-ref", "implementation", and
  2101 "system") have been updated and extended.  Formally checked references
  2102 as hyperlinks are now available uniformly.
  2103 
  2104 
  2105 *** Pure ***
  2106 
  2107 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  2108 respects.  The most important changes are listed below.  See the
  2109 Tutorial on Locales ("locales" manual) for details.
  2110 
  2111 - In locale expressions, instantiation replaces renaming.  Parameters
  2112 must be declared in a for clause.  To aid compatibility with previous
  2113 parameter inheritance, in locale declarations, parameters that are not
  2114 'touched' (instantiation position "_" or omitted) are implicitly added
  2115 with their syntax at the beginning of the for clause.
  2116 
  2117 - Syntax from abbreviations and definitions in locales is available in
  2118 locale expressions and context elements.  The latter is particularly
  2119 useful in locale declarations.
  2120 
  2121 - More flexible mechanisms to qualify names generated by locale
  2122 expressions.  Qualifiers (prefixes) may be specified in locale
  2123 expressions, and can be marked as mandatory (syntax: "name!:") or
  2124 optional (syntax "name?:").  The default depends for plain "name:"
  2125 depends on the situation where a locale expression is used: in
  2126 commands 'locale' and 'sublocale' prefixes are optional, in
  2127 'interpretation' and 'interpret' prefixes are mandatory.  The old
  2128 implicit qualifiers derived from the parameter names of a locale are
  2129 no longer generated.
  2130 
  2131 - Command "sublocale l < e" replaces "interpretation l < e".  The
  2132 instantiation clause in "interpretation" and "interpret" (square
  2133 brackets) is no longer available.  Use locale expressions.
  2134 
  2135 - When converting proof scripts, mandatory qualifiers in
  2136 'interpretation' and 'interpret' should be retained by default, even
  2137 if this is an INCOMPATIBILITY compared to former behavior.  In the
  2138 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  2139 in locale expressions range over a single locale instance only.
  2140 
  2141 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  2142 In existing theorem specifications replace the includes element by the
  2143 respective context elements of the included locale, omitting those
  2144 that are already present in the theorem specification.  Multiple
  2145 assume elements of a locale should be replaced by a single one
  2146 involving the locale predicate.  In the proof body, declarations (most
  2147 notably theorems) may be regained by interpreting the respective
  2148 locales in the proof context as required (command "interpret").
  2149 
  2150 If using "includes" in replacement of a target solely because the
  2151 parameter types in the theorem are not as general as in the target,
  2152 consider declaring a new locale with additional type constraints on
  2153 the parameters (context element "constrains").
  2154 
  2155 - Discontinued "locale (open)".  INCOMPATIBILITY.
  2156 
  2157 - Locale interpretation commands no longer attempt to simplify goal.
  2158 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  2159 methods intro_locales and unfold_locales to clarify.
  2160 
  2161 - Locale interpretation commands no longer accept interpretation
  2162 attributes.  INCOMPATIBILITY.
  2163 
  2164 * Class declaration: so-called "base sort" must not be given in import
  2165 list any longer, but is inferred from the specification.  Particularly
  2166 in HOL, write
  2167 
  2168     class foo = ...
  2169 
  2170 instead of
  2171 
  2172     class foo = type + ...
  2173 
  2174 * Class target: global versions of theorems stemming do not carry a
  2175 parameter prefix any longer.  INCOMPATIBILITY.
  2176 
  2177 * Class 'instance' command no longer accepts attached definitions.
  2178 INCOMPATIBILITY, use proper 'instantiation' target instead.
  2179 
  2180 * Recovered hiding of consts, which was accidentally broken in
  2181 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  2182 makes c inaccessible; consider using ``hide (open) const c'' instead.
  2183 
  2184 * Slightly more coherent Pure syntax, with updated documentation in
  2185 isar-ref manual.  Removed locales meta_term_syntax and
  2186 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  2187 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  2188 directly in regular applications.
  2189 
  2190 * There is a new syntactic category "float_const" for signed decimal
  2191 fractions (e.g. 123.45 or -123.45).
  2192 
  2193 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  2194 interface with 'setup' command instead.
  2195 
  2196 * Command 'local_setup' is similar to 'setup', but operates on a local
  2197 theory context.
  2198 
  2199 * The 'axiomatization' command now only works within a global theory
  2200 context.  INCOMPATIBILITY.
  2201 
  2202 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  2203 hypotheses.  Sorts required in the course of reasoning need to be
  2204 covered by the constraints in the initial statement, completed by the
  2205 type instance information of the background theory.  Non-trivial sort
  2206 hypotheses, which rarely occur in practice, may be specified via
  2207 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  2208 
  2209   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  2210 
  2211 The result contains an implicit sort hypotheses as before --
  2212 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  2213 normalization.
  2214 
  2215 * Generalized Isar history, with support for linear undo, direct state
  2216 addressing etc.
  2217 
  2218 * Changed defaults for unify configuration options:
  2219 
  2220   unify_trace_bound = 50 (formerly 25)
  2221   unify_search_bound = 60 (formerly 30)
  2222 
  2223 * Different bookkeeping for code equations (INCOMPATIBILITY):
  2224 
  2225   a) On theory merge, the last set of code equations for a particular
  2226      constant is taken (in accordance with the policy applied by other
  2227      parts of the code generator framework).
  2228 
  2229   b) Code equations stemming from explicit declarations (e.g. code
  2230      attribute) gain priority over default code equations stemming
  2231      from definition, primrec, fun etc.
  2232 
  2233 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  2234 
  2235 * Unified theorem tables for both code generators.  Thus [code
  2236 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  2237 
  2238 * Command 'find_consts' searches for constants based on type and name
  2239 patterns, e.g.
  2240 
  2241     find_consts "_ => bool"
  2242 
  2243 By default, matching is against subtypes, but it may be restricted to
  2244 the whole type.  Searching by name is possible.  Multiple queries are
  2245 conjunctive and queries may be negated by prefixing them with a
  2246 hyphen:
  2247 
  2248     find_consts strict: "_ => bool" name: "Int" -"int => int"
  2249 
  2250 * New 'find_theorems' criterion "solves" matches theorems that
  2251 directly solve the current goal (modulo higher-order unification).
  2252 
  2253 * Auto solve feature for main theorem statements: whenever a new goal
  2254 is stated, "find_theorems solves" is called; any theorems that could
  2255 solve the lemma directly are listed as part of the goal state.
  2256 Cf. associated options in Proof General Isabelle settings menu,
  2257 enabled by default, with reasonable timeout for pathological cases of
  2258 higher-order unification.
  2259 
  2260 
  2261 *** Document preparation ***
  2262 
  2263 * Antiquotation @{lemma} now imitates a regular terminal proof,
  2264 demanding keyword 'by' and supporting the full method expression
  2265 syntax just like the Isar command 'by'.
  2266 
  2267 
  2268 *** HOL ***
  2269 
  2270 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  2271 points Main and Complex_Main remain as before.
  2272 
  2273 * Logic image HOL-Plain provides a minimal HOL with the most important
  2274 tools available (inductive, datatype, primrec, ...).  This facilitates
  2275 experimentation and tool development.  Note that user applications
  2276 (and library theories) should never refer to anything below theory
  2277 Main, as before.
  2278 
  2279 * Logic image HOL-Main stops at theory Main, and thus facilitates
  2280 experimentation due to shorter build times.
  2281 
  2282 * Logic image HOL-NSA contains theories of nonstandard analysis which
  2283 were previously part of former HOL-Complex.  Entry point Hyperreal
  2284 remains valid, but theories formerly using Complex_Main should now use
  2285 new entry point Hypercomplex.
  2286 
  2287 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  2288 Posix processes.  Avoids potentially expensive forking of the ML
  2289 process.  New thread-based implementation also works on non-Unix
  2290 platforms (Cygwin).  Provers are no longer hardwired, but defined
  2291 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  2292 commands are covered in the isar-ref manual.
  2293 
  2294 * Wrapper scripts for remote SystemOnTPTP service allows to use
  2295 sledgehammer without local ATP installation (Vampire etc.). Other
  2296 provers may be included via suitable ML wrappers, see also
  2297 src/HOL/ATP_Linkup.thy.
  2298 
  2299 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  2300 menu.
  2301 
  2302 * The metis method no longer fails because the theorem is too trivial
  2303 (contains the empty clause).
  2304 
  2305 * The metis method now fails in the usual manner, rather than raising
  2306 an exception, if it determines that it cannot prove the theorem.
  2307 
  2308 * Method "coherent" implements a prover for coherent logic (see also
  2309 src/Tools/coherent.ML).
  2310 
  2311 * Constants "undefined" and "default" replace "arbitrary".  Usually
  2312 "undefined" is the right choice to replace "arbitrary", though
  2313 logically there is no difference.  INCOMPATIBILITY.
  2314 
  2315 * Command "value" now integrates different evaluation mechanisms.  The
  2316 result of the first successful evaluation mechanism is printed.  In
  2317 square brackets a particular named evaluation mechanisms may be
  2318 specified (currently, [SML], [code] or [nbe]).  See further
  2319 src/HOL/ex/Eval_Examples.thy.
  2320 
  2321 * Normalization by evaluation now allows non-leftlinear equations.
  2322 Declare with attribute [code nbe].
  2323 
  2324 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  2325 as the structured Isar versions "cases" and "induct", cf. the
  2326 corresponding "cases" and "induct" attributes.  Mutual induction rules
  2327 are now presented as a list of individual projections
  2328 (e.g. foo_bar.inducts for types foo and bar); the old format with
  2329 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  2330 rare situations a different rule is selected --- notably nested tuple
  2331 elimination instead of former prod.exhaust: use explicit (case_tac t
  2332 rule: prod.exhaust) here.
  2333 
  2334 * Attributes "cases", "induct", "coinduct" support "del" option.
  2335 
  2336 * Removed fact "case_split_thm", which duplicates "case_split".
  2337 
  2338 * The option datatype has been moved to a new theory Option.  Renamed
  2339 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  2340 
  2341 * New predicate "strict_mono" classifies strict functions on partial
  2342 orders.  With strict functions on linear orders, reasoning about
  2343 (in)equalities is facilitated by theorems "strict_mono_eq",
  2344 "strict_mono_less_eq" and "strict_mono_less".
  2345 
  2346 * Some set operations are now proper qualified constants with
  2347 authentic syntax.  INCOMPATIBILITY:
  2348 
  2349     op Int ~>   Set.Int
  2350     op Un ~>    Set.Un
  2351     INTER ~>    Set.INTER
  2352     UNION ~>    Set.UNION
  2353     Inter ~>    Set.Inter
  2354     Union ~>    Set.Union
  2355     {} ~>       Set.empty
  2356     UNIV ~>     Set.UNIV
  2357 
  2358 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  2359 theory Set.
  2360 
  2361 * Auxiliary class "itself" has disappeared -- classes without any
  2362 parameter are treated as expected by the 'class' command.
  2363 
  2364 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  2365 
  2366 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  2367 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  2368 
  2369 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  2370 method "approximation".  It proves formulas on real values by using
  2371 interval arithmetic.  In the formulas are also the transcendental
  2372 functions sin, cos, tan, atan, ln, exp and the constant pi are
  2373 allowed. For examples see
  2374 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  2375 
  2376 * Theory "Reflection" now resides in HOL/Library.
  2377 
  2378 * Entry point to Word library now simply named "Word".
  2379 INCOMPATIBILITY.
  2380 
  2381 * Made source layout more coherent with logical distribution
  2382 structure:
  2383 
  2384     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  2385     src/HOL/Library/Code_Message.thy ~> src/HOL/
  2386     src/HOL/Library/GCD.thy ~> src/HOL/
  2387     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  2388     src/HOL/Library/Parity.thy ~> src/HOL/
  2389     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  2390     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  2391     src/HOL/Real/Lubs.thy ~> src/HOL/
  2392     src/HOL/Real/PReal.thy ~> src/HOL/
  2393     src/HOL/Real/Rational.thy ~> src/HOL/
  2394     src/HOL/Real/RComplete.thy ~> src/HOL/
  2395     src/HOL/Real/RealDef.thy ~> src/HOL/
  2396     src/HOL/Real/RealPow.thy ~> src/HOL/
  2397     src/HOL/Real/Real.thy ~> src/HOL/
  2398     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  2399     src/HOL/Complex/Complex.thy ~> src/HOL/
  2400     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  2401     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  2402     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  2403     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  2404     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  2405     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  2406     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  2407     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  2408     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  2409     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  2410     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  2411     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  2412     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  2413     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  2414     src/HOL/Real/Float ~> src/HOL/Library/
  2415     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  2416     src/HOL/Real/RealVector.thy ~> src/HOL/
  2417 
  2418     src/HOL/arith_data.ML ~> src/HOL/Tools
  2419     src/HOL/hologic.ML ~> src/HOL/Tools
  2420     src/HOL/simpdata.ML ~> src/HOL/Tools
  2421     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  2422     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  2423     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  2424     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  2425     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  2426     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  2427     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  2428 
  2429     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  2430     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  2431     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  2432     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  2433     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  2434     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  2435 
  2436 * If methods "eval" and "evaluation" encounter a structured proof
  2437 state with !!/==>, only the conclusion is evaluated to True (if
  2438 possible), avoiding strange error messages.
  2439 
  2440 * Method "sizechange" automates termination proofs using (a
  2441 modification of) the size-change principle.  Requires SAT solver.  See
  2442 src/HOL/ex/Termination.thy for examples.
  2443 
  2444 * Simplifier: simproc for let expressions now unfolds if bound
  2445 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  2446 
  2447 * Method "arith": Linear arithmetic now ignores all inequalities when
  2448 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  2449 
  2450 * New attribute "arith" for facts that should always be used
  2451 automatically by arithmetic. It is intended to be used locally in
  2452 proofs, e.g.
  2453 
  2454   assumes [arith]: "x > 0"
  2455 
  2456 Global usage is discouraged because of possible performance impact.
  2457 
  2458 * New classes "top" and "bot" with corresponding operations "top" and
  2459 "bot" in theory Orderings; instantiation of class "complete_lattice"
  2460 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  2461 
  2462 * Changed definition lemma "less_fun_def" in order to provide an
  2463 instance for preorders on functions; use lemma "less_le" instead.
  2464 INCOMPATIBILITY.
  2465 
  2466 * Theory Orderings: class "wellorder" moved here, with explicit
  2467 induction rule "less_induct" as assumption.  For instantiation of
  2468 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  2469 INCOMPATIBILITY.
  2470 
  2471 * Theory Orderings: added class "preorder" as superclass of "order".
  2472 INCOMPATIBILITY: Instantiation proofs for order, linorder
  2473 etc. slightly changed.  Some theorems named order_class.* now named
  2474 preorder_class.*.
  2475 
  2476 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  2477 "diag" to "Id_on".
  2478 
  2479 * Theory Finite_Set: added a new fold combinator of type
  2480 
  2481   ('a => 'b => 'b) => 'b => 'a set => 'b
  2482 
  2483 Occasionally this is more convenient than the old fold combinator
  2484 which is now defined in terms of the new one and renamed to
  2485 fold_image.
  2486 
  2487 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  2488 and "ring_simps" have been replaced by "algebra_simps" (which can be
  2489 extended with further lemmas!).  At the moment both still exist but
  2490 the former will disappear at some point.
  2491 
  2492 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  2493 class recpower.  Type-specific simp rules for various recpower types
  2494 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  2495 
  2496 rat_power_0    -> power_0
  2497 rat_power_Suc  -> power_Suc
  2498 realpow_0      -> power_0
  2499 realpow_Suc    -> power_Suc
  2500 complexpow_0   -> power_0
  2501 complexpow_Suc -> power_Suc
  2502 power_poly_0   -> power_0
  2503 power_poly_Suc -> power_Suc
  2504 
  2505 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  2506 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  2507 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  2508 of lemmas from Divides has been generalized from nat to class
  2509 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  2510 renames resulting from duplicate elimination:
  2511 
  2512     dvd_def_mod ~>          dvd_eq_mod_eq_0
  2513     zero_dvd_iff ~>         dvd_0_left_iff
  2514     dvd_0 ~>                dvd_0_right
  2515     DIVISION_BY_ZERO_DIV ~> div_by_0
  2516     DIVISION_BY_ZERO_MOD ~> mod_by_0
  2517     mult_div ~>             div_mult_self2_is_id
  2518     mult_mod ~>             mod_mult_self2_is_0
  2519 
  2520 * Theory IntDiv: removed many lemmas that are instances of class-based
  2521 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  2522 rename old lemmas as follows:
  2523 
  2524 dvd_diff               -> nat_dvd_diff
  2525 dvd_zminus_iff         -> dvd_minus_iff
  2526 mod_add1_eq            -> mod_add_eq
  2527 mod_mult1_eq           -> mod_mult_right_eq
  2528 mod_mult1_eq'          -> mod_mult_left_eq
  2529 mod_mult_distrib_mod   -> mod_mult_eq
  2530 nat_mod_add_left_eq    -> mod_add_left_eq
  2531 nat_mod_add_right_eq   -> mod_add_right_eq
  2532 nat_mod_div_trivial    -> mod_div_trivial
  2533 nat_mod_mod_trivial    -> mod_mod_trivial
  2534 zdiv_zadd_self1        -> div_add_self1
  2535 zdiv_zadd_self2        -> div_add_self2
  2536 zdiv_zmult_self1       -> div_mult_self2_is_id
  2537 zdiv_zmult_self2       -> div_mult_self1_is_id
  2538 zdvd_triv_left         -> dvd_triv_left
  2539 zdvd_triv_right        -> dvd_triv_right
  2540 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  2541 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  2542 zmod_zadd_left_eq      -> mod_add_left_eq
  2543 zmod_zadd_right_eq     -> mod_add_right_eq
  2544 zmod_zadd_self1        -> mod_add_self1
  2545 zmod_zadd_self2        -> mod_add_self2
  2546 zmod_zadd1_eq          -> mod_add_eq
  2547 zmod_zdiff1_eq         -> mod_diff_eq
  2548 zmod_zdvd_zmod         -> mod_mod_cancel
  2549 zmod_zmod_cancel       -> mod_mod_cancel
  2550 zmod_zmult_self1       -> mod_mult_self2_is_0
  2551 zmod_zmult_self2       -> mod_mult_self1_is_0
  2552 zmod_1                 -> mod_by_1
  2553 zdiv_1                 -> div_by_1
  2554 zdvd_abs1              -> abs_dvd_iff
  2555 zdvd_abs2              -> dvd_abs_iff
  2556 zdvd_refl              -> dvd_refl
  2557 zdvd_trans             -> dvd_trans
  2558 zdvd_zadd              -> dvd_add
  2559 zdvd_zdiff             -> dvd_diff
  2560 zdvd_zminus_iff        -> dvd_minus_iff
  2561 zdvd_zminus2_iff       -> minus_dvd_iff
  2562 zdvd_zmultD            -> dvd_mult_right
  2563 zdvd_zmultD2           -> dvd_mult_left
  2564 zdvd_zmult_mono        -> mult_dvd_mono
  2565 zdvd_0_right           -> dvd_0_right
  2566 zdvd_0_left            -> dvd_0_left_iff
  2567 zdvd_1_left            -> one_dvd
  2568 zminus_dvd_iff         -> minus_dvd_iff
  2569 
  2570 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  2571 
  2572 * The real numbers offer decimal input syntax: 12.34 is translated
  2573 into 1234/10^2. This translation is not reversed upon output.
  2574 
  2575 * Theory Library/Polynomial defines an abstract type 'a poly of
  2576 univariate polynomials with coefficients of type 'a.  In addition to
  2577 the standard ring operations, it also supports div and mod.  Code
  2578 generation is also supported, using list-style constructors.
  2579 
  2580 * Theory Library/Inner_Product defines a class of real_inner for real
  2581 inner product spaces, with an overloaded operation inner :: 'a => 'a
  2582 => real.  Class real_inner is a subclass of real_normed_vector from
  2583 theory RealVector.
  2584 
  2585 * Theory Library/Product_Vector provides instances for the product
  2586 type 'a * 'b of several classes from RealVector and Inner_Product.
  2587 Definitions of addition, subtraction, scalar multiplication, norms,
  2588 and inner products are included.
  2589 
  2590 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  2591 addition to the field operations, numerals and case syntax are also
  2592 supported.
  2593 
  2594 * Theory Library/Diagonalize provides constructive version of Cantor's
  2595 first diagonalization argument.
  2596 
  2597 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  2598 zlcm (for int); carried together from various gcd/lcm developements in
  2599 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  2600 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  2601 may recover tupled syntax as follows:
  2602 
  2603     hide (open) const gcd
  2604     abbreviation gcd where
  2605       "gcd == (%(a, b). GCD.gcd a b)"
  2606     notation (output)
  2607       GCD.gcd ("gcd '(_, _')")
  2608 
  2609 The same works for lcm, zgcd, zlcm.
  2610 
  2611 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  2612 instantiations for algebraic structures.  Removed some duplicate
  2613 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  2614 
  2615 * ML antiquotation @{code} takes a constant as argument and generates
  2616 corresponding code in background and inserts name of the corresponding
  2617 resulting ML value/function/datatype constructor binding in place.
  2618 All occurrences of @{code} with a single ML block are generated
  2619 simultaneously.  Provides a generic and safe interface for
  2620 instrumentalizing code generation.  See
  2621 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  2622 In future you ought to refrain from ad-hoc compiling generated SML
  2623 code on the ML toplevel.  Note that (for technical reasons) @{code}
  2624 cannot refer to constants for which user-defined serializations are
  2625 set.  Refer to the corresponding ML counterpart directly in that
  2626 cases.
  2627 
  2628 * Command 'rep_datatype': instead of theorem names the command now
  2629 takes a list of terms denoting the constructors of the type to be
  2630 represented as datatype.  The characteristic theorems have to be
  2631 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  2632 have disappeared in favour of existing ones:
  2633 
  2634     unit_induct                 ~> unit.induct
  2635     prod_induct                 ~> prod.induct
  2636     sum_induct                  ~> sum.induct
  2637     Suc_Suc_eq                  ~> nat.inject
  2638     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  2639 
  2640 
  2641 *** HOL-Algebra ***
  2642 
  2643 * New locales for orders and lattices where the equivalence relation
  2644 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  2645 locales use a record structure with field eq for the equivalence.
  2646 
  2647 * New theory of factorial domains.
  2648 
  2649 * Units_l_inv and Units_r_inv are now simp rules by default.
  2650 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  2651 and/or r_inv will now also require deletion of these lemmas.
  2652 
  2653 * Renamed the following theorems, INCOMPATIBILITY:
  2654 
  2655 UpperD ~> Upper_memD
  2656 LowerD ~> Lower_memD
  2657 least_carrier ~> least_closed
  2658 greatest_carrier ~> greatest_closed
  2659 greatest_Lower_above ~> greatest_Lower_below
  2660 one_zero ~> carrier_one_zero
  2661 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  2662 
  2663 
  2664 *** HOL-Nominal ***
  2665 
  2666 * Nominal datatypes can now contain type-variables.
  2667 
  2668 * Commands 'nominal_inductive' and 'equivariance' work with local
  2669 theory targets.
  2670 
  2671 * Nominal primrec can now works with local theory targets and its
  2672 specification syntax now conforms to the general format as seen in
  2673 'inductive' etc.
  2674 
  2675 * Method "perm_simp" honours the standard simplifier attributes
  2676 (no_asm), (no_asm_use) etc.
  2677 
  2678 * The new predicate #* is defined like freshness, except that on the
  2679 left hand side can be a set or list of atoms.
  2680 
  2681 * Experimental command 'nominal_inductive2' derives strong induction
  2682 principles for inductive definitions.  In contrast to
  2683 'nominal_inductive', which can only deal with a fixed number of
  2684 binders, it can deal with arbitrary expressions standing for sets of
  2685 atoms to be avoided.  The only inductive definition we have at the
  2686 moment that needs this generalisation is the typing rule for Lets in
  2687 the algorithm W:
  2688 
  2689  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  2690  -----------------------------------------------------------------
  2691          Gamma |- Let x be t1 in t2 : T2
  2692 
  2693 In this rule one wants to avoid all the binders that are introduced by
  2694 "close Gamma T1".  We are looking for other examples where this
  2695 feature might be useful.  Please let us know.
  2696 
  2697 
  2698 *** HOLCF ***
  2699 
  2700 * Reimplemented the simplification procedure for proving continuity
  2701 subgoals.  The new simproc is extensible; users can declare additional
  2702 continuity introduction rules with the attribute [cont2cont].
  2703 
  2704 * The continuity simproc now uses a different introduction rule for
  2705 solving continuity subgoals on terms with lambda abstractions.  In
  2706 some rare cases the new simproc may fail to solve subgoals that the
  2707 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  2708 Potential INCOMPATIBILITY.
  2709 
  2710 * Command 'fixrec': specification syntax now conforms to the general
  2711 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  2712 examples.  INCOMPATIBILITY.
  2713 
  2714 
  2715 *** ZF ***
  2716 
  2717 * Proof of Zorn's Lemma for partial orders.
  2718 
  2719 
  2720 *** ML ***
  2721 
  2722 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  2723 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  2724 depends on multithreading, so timouts will not work before Poly/ML
  2725 5.2.1!
  2726 
  2727 * High-level support for concurrent ML programming, see
  2728 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  2729 particularly convenient to organize independent functional
  2730 computations.  The concept of "synchronized variables" provides a
  2731 higher-order interface for components with shared state, avoiding the
  2732 delicate details of mutexes and condition variables.  (Requires
  2733 Poly/ML 5.2.1 or later.)
  2734 
  2735 * ML bindings produced via Isar commands are stored within the Isar
  2736 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2737 become thread-safe and work with undo as expected (concerning
  2738 top-level bindings, not side-effects on global references).
  2739 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2740 compiler at runtime; really global bindings need to be given outside a
  2741 theory.  (Requires Poly/ML 5.2 or later.)
  2742 
  2743 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2744 context.  Top-level ML bindings are stored within the proof context in
  2745 a purely sequential fashion, disregarding the nested proof structure.
  2746 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2747 proof.  (Requires Poly/ML 5.2 or later.)
  2748 
  2749 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2750 and Method.setup, as well as Isar commands 'attribute_setup' and
  2751 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2752 existing code accordingly, or use plain 'setup' together with old
  2753 Method.add_method.
  2754 
  2755 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2756 to 'a -> thm, while results are always tagged with an authentic oracle
  2757 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2758 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2759 accordingly.  Note that extra performance may be gained by producing
  2760 the cterm carefully, avoiding slow Thm.cterm_of.
  2761 
  2762 * Simplified interface for defining document antiquotations via
  2763 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2764 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2765 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2766 examples.
  2767 
  2768 * More systematic treatment of long names, abstract name bindings, and
  2769 name space operations.  Basic operations on qualified names have been
  2770 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2771 Long_Name.append.  Old type bstring has been mostly replaced by
  2772 abstract type binding (see structure Binding), which supports precise
  2773 qualification by packages and local theory targets, as well as proper
  2774 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2775 bstring values into Binding.name, or better pass through abstract
  2776 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2777 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2778 
  2779 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2780 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2781 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2782 
  2783 * Disposed old type and term read functions (Sign.read_def_typ,
  2784 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2785 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2786 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2787 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2788 resort for legacy applications.
  2789 
  2790 * Disposed old declarations, tactics, tactic combinators that refer to
  2791 the simpset or claset of an implicit theory (such as Addsimps,
  2792 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2793 embedded ML text, or local_simpset_of with a proper context passed as
  2794 explicit runtime argument.
  2795 
  2796 * Rules and tactics that read instantiations (read_instantiate,
  2797 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2798 context, which is required for parsing and type-checking.  Moreover,
  2799 the variables are specified as plain indexnames, not string encodings
  2800 thereof.  INCOMPATIBILITY.
  2801 
  2802 * Generic Toplevel.add_hook interface allows to analyze the result of
  2803 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2804 for theorem dependency output of transactions resulting in a new
  2805 theory state.
  2806 
  2807 * ML antiquotations: block-structured compilation context indicated by
  2808 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2809 
  2810   @{binding name}                         - basic name binding
  2811   @{let ?pat = term}                      - term abbreviation (HO matching)
  2812   @{note name = fact}                     - fact abbreviation
  2813   @{thm fact}                             - singleton fact (with attributes)
  2814   @{thms fact}                            - general fact (with attributes)
  2815   @{lemma prop by method}                 - singleton goal
  2816   @{lemma prop by meth1 meth2}            - singleton goal
  2817   @{lemma prop1 ... propN by method}      - general goal
  2818   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2819   @{lemma (open) ...}                     - open derivation
  2820 
  2821 
  2822 *** System ***
  2823 
  2824 * The Isabelle "emacs" tool provides a specific interface to invoke
  2825 Proof General / Emacs, with more explicit failure if that is not
  2826 installed (the old isabelle-interface script silently falls back on
  2827 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2828 installation location of the Proof General distribution.
  2829 
  2830 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2831 the Isabelle process into a JVM/Scala application.  See
  2832 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2833 process wrapper has been discontinued.)
  2834 
  2835 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2836 
  2837 * Various status messages (with exact source position information) are
  2838 emitted, if proper markup print mode is enabled.  This allows
  2839 user-interface components to provide detailed feedback on internal
  2840 prover operations.
  2841 
  2842 
  2843 
  2844 New in Isabelle2008 (June 2008)
  2845 -------------------------------
  2846 
  2847 *** General ***
  2848 
  2849 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2850 and updated, with formally checked references as hyperlinks.
  2851 
  2852 * Theory loader: use_thy (and similar operations) no longer set the
  2853 implicit ML context, which was occasionally hard to predict and in
  2854 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2855 provides a proper context already.
  2856 
  2857 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2858 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2859 'use' within a theory file will do the job.
  2860 
  2861 * Name space merge now observes canonical order, i.e. the second space
  2862 is inserted into the first one, while existing entries in the first
  2863 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2864 swap theory imports.
  2865 
  2866 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2867 INCOMPATIBILITY in identifier syntax etc.
  2868 
  2869 * Outer syntax: string tokens no longer admit escaped white space,
  2870 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2871 white space without escapes.
  2872 
  2873 * Outer syntax: string tokens may contain arbitrary character codes
  2874 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2875 "foo_bar".
  2876 
  2877 
  2878 *** Pure ***
  2879 
  2880 * Context-dependent token translations.  Default setup reverts locally
  2881 fixed variables, and adds hilite markup for undeclared frees.
  2882 
  2883 * Unused theorems can be found using the new command 'unused_thms'.
  2884 There are three ways of invoking it:
  2885 
  2886 (1) unused_thms
  2887      Only finds unused theorems in the current theory.
  2888 
  2889 (2) unused_thms thy_1 ... thy_n -
  2890      Finds unused theorems in the current theory and all of its ancestors,
  2891      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2892 
  2893 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2894      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2895      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2896      their ancestors.
  2897 
  2898 In order to increase the readability of the list produced by
  2899 unused_thms, theorems that have been created by a particular instance
  2900 of a theory command such as 'inductive' or 'function' are considered
  2901 to belong to the same "group", meaning that if at least one theorem in
  2902 this group is used, the other theorems in the same group are no longer
  2903 reported as unused.  Moreover, if all theorems in the group are
  2904 unused, only one theorem in the group is displayed.
  2905 
  2906 Note that proof objects have to be switched on in order for
  2907 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2908 usually the case when using Proof General with the default settings).
  2909 
  2910 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2911 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2912 duplicate fact bindings, or even accidental fact duplications.  Note
  2913 that tools may maintain dynamically scoped facts systematically, using
  2914 PureThy.add_thms_dynamic.
  2915 
  2916 * Command 'hide' now allows to hide from "fact" name space as well.
  2917 
  2918 * Eliminated destructive theorem database, simpset, claset, and
  2919 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2920 update of theories within ML code.
  2921 
  2922 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2923 INCOMPATIBILITY, object-logics depending on former Pure require
  2924 additional setup PureThy.old_appl_syntax_setup; object-logics
  2925 depending on former CPure need to refer to Pure.
  2926 
  2927 * Commands 'use' and 'ML' are now purely functional, operating on
  2928 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2929 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2930 INCOMPATIBILITY.
  2931 
  2932 * Command 'setup': discontinued implicit version with ML reference.
  2933 
  2934 * Instantiation target allows for simultaneous specification of class
  2935 instance operations together with an instantiation proof.
  2936 Type-checking phase allows to refer to class operations uniformly.
  2937 See src/HOL/Complex/Complex.thy for an Isar example and
  2938 src/HOL/Library/Eval.thy for an ML example.
  2939 
  2940 * Indexing of literal facts: be more serious about including only
  2941 facts from the visible specification/proof context, but not the
  2942 background context (locale etc.).  Affects `prop` notation and method
  2943 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2944 situations.
  2945 
  2946 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2947 "(open)" option, which used to expose internal bound variables to the
  2948 proof text.
  2949 
  2950 * Isar statements: removed obsolete case "rule_context".
  2951 INCOMPATIBILITY, better use explicit fixes/assumes.
  2952 
  2953 * Locale proofs: default proof step now includes 'unfold_locales';
  2954 hence 'proof' without argument may be used to unfold locale
  2955 predicates.
  2956 
  2957 
  2958 *** Document preparation ***
  2959 
  2960 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2961 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2962 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2963 spot); renamed link color from "darkblue" to "linkcolor" (default
  2964 value unchanged, can be redefined via \definecolor); no longer sets
  2965 "a4paper" option (unnecessary or even intrusive).
  2966 
  2967 * Antiquotation @{lemma A method} proves proposition A by the given
  2968 method (either a method name or a method name plus (optional) method
  2969 arguments in parentheses) and prints A just like @{prop A}.
  2970 
  2971 
  2972 *** HOL ***
  2973 
  2974 * New primrec package.  Specification syntax conforms in style to
  2975 definition/function/....  No separate induction rule is provided.  The
  2976 "primrec" command distinguishes old-style and new-style specifications
  2977 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2978 When adjusting theories, beware: constants stemming from new-style
  2979 primrec specifications have authentic syntax.
  2980 
  2981 * Metis prover is now an order of magnitude faster, and also works
  2982 with multithreading.
  2983 
  2984 * Metis: the maximum number of clauses that can be produced from a
  2985 theorem is now given by the attribute max_clauses.  Theorems that
  2986 exceed this number are ignored, with a warning printed.
  2987 
  2988 * Sledgehammer no longer produces structured proofs by default. To
  2989 enable, declare [[sledgehammer_full = true]].  Attributes
  2990 reconstruction_modulus, reconstruction_sorts renamed
  2991 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2992 
  2993 * Method "induct_scheme" derives user-specified induction rules
  2994 from well-founded induction and completeness of patterns. This factors
  2995 out some operations that are done internally by the function package
  2996 and makes them available separately.  See
  2997 src/HOL/ex/Induction_Scheme.thy for examples.
  2998 
  2999 * More flexible generation of measure functions for termination
  3000 proofs: Measure functions can be declared by proving a rule of the
  3001 form "is_measure f" and giving it the [measure_function] attribute.
  3002 The "is_measure" predicate is logically meaningless (always true), and
  3003 just guides the heuristic.  To find suitable measure functions, the
  3004 termination prover sets up the goal "is_measure ?f" of the appropriate
  3005 type and generates all solutions by prolog-style backwards proof using
  3006 the declared rules.
  3007 
  3008 This setup also deals with rules like 
  3009 
  3010   "is_measure f ==> is_measure (list_size f)"
  3011 
  3012 which accommodates nested datatypes that recurse through lists.
  3013 Similar rules are predeclared for products and option types.
  3014 
  3015 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  3016 
  3017   INCOMPATIBILITIES:
  3018 
  3019   - Definitions of overloaded constants on sets have to be replaced by
  3020     definitions on => and bool.
  3021 
  3022   - Some definitions of overloaded operators on sets can now be proved
  3023     using the definitions of the operators on => and bool.  Therefore,
  3024     the following theorems have been renamed:
  3025 
  3026       subset_def   -> subset_eq
  3027       psubset_def  -> psubset_eq
  3028       set_diff_def -> set_diff_eq
  3029       Compl_def    -> Compl_eq
  3030       Sup_set_def  -> Sup_set_eq
  3031       Inf_set_def  -> Inf_set_eq
  3032       sup_set_def  -> sup_set_eq
  3033       inf_set_def  -> inf_set_eq
  3034 
  3035   - Due to the incompleteness of the HO unification algorithm, some
  3036     rules such as subst may require manual instantiation, if some of
  3037     the unknowns in the rule is a set.
  3038 
  3039   - Higher order unification and forward proofs:
  3040     The proof pattern
  3041 
  3042       have "P (S::'a set)" <...>
  3043       then have "EX S. P S" ..
  3044 
  3045     no longer works (due to the incompleteness of the HO unification
  3046     algorithm) and must be replaced by the pattern
  3047 
  3048       have "EX S. P S"
  3049       proof
  3050         show "P S" <...>
  3051       qed
  3052 
  3053   - Calculational reasoning with subst (or similar rules):
  3054     The proof pattern
  3055 
  3056       have "P (S::'a set)" <...>
  3057       also have "S = T" <...>
  3058       finally have "P T" .
  3059 
  3060     no longer works (for similar reasons as the previous example) and
  3061     must be replaced by something like
  3062 
  3063       have "P (S::'a set)" <...>
  3064       moreover have "S = T" <...>
  3065       ultimately have "P T" by simp
  3066 
  3067   - Tactics or packages written in ML code:
  3068     Code performing pattern matching on types via
  3069 
  3070       Type ("set", [T]) => ...
  3071 
  3072     must be rewritten. Moreover, functions like strip_type or
  3073     binder_types no longer return the right value when applied to a
  3074     type of the form
  3075 
  3076       T1 => ... => Tn => U => bool
  3077 
  3078     rather than
  3079 
  3080       T1 => ... => Tn => U set
  3081 
  3082 * Merged theories Wellfounded_Recursion, Accessible_Part and
  3083 Wellfounded_Relations to theory Wellfounded.
  3084 
  3085 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  3086 
  3087 * Class finite no longer treats UNIV as class parameter.  Use class
  3088 enum from theory Library/Enum instead to achieve a similar effect.
  3089 INCOMPATIBILITY.
  3090 
  3091 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  3092 and "Cons".  INCOMPATIBILITY.
  3093 
  3094 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  3095 Potential INCOMPATIBILITY.
  3096 
  3097 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  3098 injective_fst_snd removed, use split_eta and prod_eqI instead.
  3099 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  3100 
  3101 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  3102 the same name in theory Orderings:
  3103 
  3104   less_trans
  3105   less_linear
  3106   le_imp_less_or_eq
  3107   le_less_trans
  3108   less_le_trans
  3109   less_not_sym
  3110   less_asym
  3111 
  3112 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  3113 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  3114 and different variable names.
  3115 
  3116 * Library/Option_ord.thy: Canonical order on option type.
  3117 
  3118 * Library/RBT.thy: Red-black trees, an efficient implementation of
  3119 finite maps.
  3120 
  3121 * Library/Countable.thy: Type class for countable types.
  3122 
  3123 * Theory Int: The representation of numerals has changed.  The infix
  3124 operator BIT and the bit datatype with constructors B0 and B1 have
  3125 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  3126 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  3127 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  3128 accordingly.
  3129 
  3130 * Theory Nat: definition of <= and < on natural numbers no longer
  3131 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  3132 le_def and less_def have disappeared.  Consider lemmas not_less
  3133 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  3134 
  3135 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  3136 (whose purpose mainly is for various fold_set functionals) have been
  3137 abandoned in favor of the existing algebraic classes
  3138 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  3139 lower_semilattice (resp. upper_semilattice) and linorder.
  3140 INCOMPATIBILITY.
  3141 
  3142 * Theory Transitive_Closure: induct and cases rules now declare proper
  3143 case_names ("base" and "step").  INCOMPATIBILITY.
  3144 
  3145 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  3146 lattices.  The form set-specific version is available as
  3147 Inductive.lfp_ordinal_induct_set.
  3148 
  3149 * Renamed theorems "power.simps" to "power_int.simps".
  3150 INCOMPATIBILITY.
  3151 
  3152 * Class semiring_div provides basic abstract properties of semirings
  3153 with division and modulo operations.  Subsumes former class dvd_mod.
  3154 
  3155 * Merged theories IntDef, Numeral and IntArith into unified theory
  3156 Int.  INCOMPATIBILITY.
  3157 
  3158 * Theory Library/Code_Index: type "index" now represents natural
  3159 numbers rather than integers.  INCOMPATIBILITY.
  3160 
  3161 * New class "uminus" with operation "uminus" (split of from class
  3162 "minus" which now only has operation "minus", binary).
  3163 INCOMPATIBILITY.
  3164 
  3165 * Constants "card", "internal_split", "option_map" now with authentic
  3166 syntax.  INCOMPATIBILITY.
  3167 
  3168 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  3169 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  3170 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  3171 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  3172 Sup_set_def, le_def, less_def, option_map_def now with object
  3173 equality.  INCOMPATIBILITY.
  3174 
  3175 * Records. Removed K_record, and replaced it by pure lambda term
  3176 %x. c. The simplifier setup is now more robust against eta expansion.
  3177 INCOMPATIBILITY: in cases explicitly referring to K_record.
  3178 
  3179 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  3180 
  3181 * Library/ListVector: new theory of arithmetic vector operations.
  3182 
  3183 * Library/Order_Relation: new theory of various orderings as sets of
  3184 pairs.  Defines preorders, partial orders, linear orders and
  3185 well-orders on sets and on types.
  3186 
  3187 
  3188 *** ZF ***
  3189 
  3190 * Renamed some theories to allow to loading both ZF and HOL in the
  3191 same session:
  3192 
  3193   Datatype  -> Datatype_ZF
  3194   Inductive -> Inductive_ZF
  3195   Int       -> Int_ZF
  3196   IntDiv    -> IntDiv_ZF
  3197   Nat       -> Nat_ZF
  3198   List      -> List_ZF
  3199   Main      -> Main_ZF
  3200 
  3201 INCOMPATIBILITY: ZF theories that import individual theories below
  3202 Main might need to be adapted.  Regular theory Main is still
  3203 available, as trivial extension of Main_ZF.
  3204 
  3205 
  3206 *** ML ***
  3207 
  3208 * ML within Isar: antiquotation @{const name} or @{const
  3209 name(typargs)} produces statically-checked Const term.
  3210 
  3211 * Functor NamedThmsFun: data is available to the user as dynamic fact
  3212 (of the same name).  Removed obsolete print command.
  3213 
  3214 * Removed obsolete "use_legacy_bindings" function.
  3215 
  3216 * The ``print mode'' is now a thread-local value derived from a global
  3217 template (the former print_mode reference), thus access becomes
  3218 non-critical.  The global print_mode reference is for session
  3219 management only; user-code should use print_mode_value,
  3220 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  3221 
  3222 * Functions system/system_out provide a robust way to invoke external
  3223 shell commands, with propagation of interrupts (requires Poly/ML
  3224 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  3225 
  3226 
  3227 *** System ***
  3228 
  3229 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  3230 in accordance with Proof General 3.7, which prefers GNU emacs.
  3231 
  3232 * isatool tty runs Isabelle process with plain tty interaction;
  3233 optional line editor may be specified via ISABELLE_LINE_EDITOR
  3234 setting, the default settings attempt to locate "ledit" and "rlwrap".
  3235 
  3236 * isatool browser now works with Cygwin as well, using general
  3237 "javapath" function defined in Isabelle process environment.
  3238 
  3239 * YXML notation provides a simple and efficient alternative to
  3240 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  3241 isatool yxml as described in the Isabelle system manual.
  3242 
  3243 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  3244 provides general wrapper for managing an Isabelle process in a robust
  3245 fashion, with ``cooked'' output from stdin/stderr.
  3246 
  3247 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  3248 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  3249 
  3250 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  3251 way of changing the user's settings is via
  3252 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  3253 script.
  3254 
  3255 * Multithreading.max_threads := 0 refers to the number of actual CPU
  3256 cores of the underlying machine, which is a good starting point for
  3257 optimal performance tuning.  The corresponding usedir option -M allows
  3258 "max" as an alias for "0".  WARNING: does not work on certain versions
  3259 of Mac OS (with Poly/ML 5.1).
  3260 
  3261 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  3262 adverse effect of Isabelle flooding interactive front-ends (notably
  3263 ProofGeneral / XEmacs).
  3264 
  3265 
  3266 
  3267 New in Isabelle2007 (November 2007)
  3268 -----------------------------------
  3269 
  3270 *** General ***
  3271 
  3272 * More uniform information about legacy features, notably a
  3273 warning/error of "Legacy feature: ...", depending on the state of the
  3274 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  3275 legacy features will disappear eventually.
  3276 
  3277 * Theory syntax: the header format ``theory A = B + C:'' has been
  3278 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  3279 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  3280 
  3281 * Theory syntax: the old non-Isar theory file format has been
  3282 discontinued altogether.  Note that ML proof scripts may still be used
  3283 with Isar theories; migration is usually quite simple with the ML
  3284 function use_legacy_bindings.  INCOMPATIBILITY.
  3285 
  3286 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  3287 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  3288 quotes.
  3289 
  3290 * Theory loader: be more serious about observing the static theory
  3291 header specifications (including optional directories), but not the
  3292 accidental file locations of previously successful loads.  The strict
  3293 update policy of former update_thy is now already performed by
  3294 use_thy, so the former has been removed; use_thys updates several
  3295 theories simultaneously, just as 'imports' within a theory header
  3296 specification, but without merging the results.  Potential
  3297 INCOMPATIBILITY: may need to refine theory headers and commands
  3298 ROOT.ML which depend on load order.
  3299 
  3300 * Theory loader: optional support for content-based file
  3301 identification, instead of the traditional scheme of full physical
  3302 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  3303 (cf. the system manual).  The new scheme allows to work with
  3304 non-finished theories in persistent session images, such that source
  3305 files may be moved later on without requiring reloads.
  3306 
  3307 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3308 file (with the same base name as the theory) are considered a legacy
  3309 feature, which will disappear eventually. Even now, the theory loader
  3310 no longer maintains dependencies on such files.
  3311 
  3312 * Syntax: the scope for resolving ambiguities via type-inference is
  3313 now limited to individual terms, instead of whole simultaneous
  3314 specifications as before. This greatly reduces the complexity of the
  3315 syntax module and improves flexibility by separating parsing and
  3316 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  3317 'fixes' etc.) are required in rare situations.
  3318 
  3319 * Syntax: constants introduced by new-style packages ('definition',
  3320 'abbreviation' etc.) are passed through the syntax module in
  3321 ``authentic mode''. This means that associated mixfix annotations
  3322 really stick to such constants, independently of potential name space
  3323 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  3324 trees are represented slightly differently, may need to adapt syntax
  3325 translations accordingly. Use CONST marker in 'translations' and
  3326 @{const_syntax} antiquotation in 'parse_translation' etc.
  3327 
  3328 * Legacy goal package: reduced interface to the bare minimum required
  3329 to keep existing proof scripts running.  Most other user-level
  3330 functions are now part of the OldGoals structure, which is *not* open
  3331 by default (consider isatool expandshort before open OldGoals).
  3332 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  3333 these tend to cause confusion about the actual goal (!) context being
  3334 used here, which is not necessarily the same as the_context().
  3335 
  3336 * Command 'find_theorems': supports "*" wild-card in "name:"
  3337 criterion; "with_dups" option.  Certain ProofGeneral versions might
  3338 support a specific search form (see ProofGeneral/CHANGES).
  3339 
  3340 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  3341 by default, which means that "prems" (and also "fixed variables") are
  3342 suppressed from proof state output.  Note that the ProofGeneral
  3343 settings mechanism allows to change and save options persistently, but
  3344 older versions of Isabelle will fail to start up if a negative prems
  3345 limit is imposed.
  3346 
  3347 * Local theory targets may be specified by non-nested blocks of
  3348 ``context/locale/class ... begin'' followed by ``end''.  The body may
  3349 contain definitions, theorems etc., including any derived mechanism
  3350 that has been implemented on top of these primitives.  This concept
  3351 generalizes the existing ``theorem (in ...)'' towards more versatility
  3352 and scalability.
  3353 
  3354 * Proof General interface: proper undo of final 'end' command;
  3355 discontinued Isabelle/classic mode (ML proof scripts).
  3356 
  3357 
  3358 *** Document preparation ***
  3359 
  3360 * Added antiquotation @{theory name} which prints the given name,
  3361 after checking that it refers to a valid ancestor theory in the
  3362 current context.
  3363 
  3364 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  3365 check the given source text as ML type/structure, printing verbatim.
  3366 
  3367 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  3368 "c args == rhs" given in the current context.  (Any number of
  3369 arguments may be given on the LHS.)
  3370 
  3371 
  3372 *** Pure ***
  3373 
  3374 * The 'class' package offers a combination of axclass and locale to
  3375 achieve Haskell-like type classes in Isabelle.  Definitions and
  3376 theorems within a class context produce both relative results (with
  3377 implicit parameters according to the locale context), and polymorphic
  3378 constants with qualified polymorphism (according to the class
  3379 context).  Within the body context of a 'class' target, a separate
  3380 syntax layer ("user space type system") takes care of converting
  3381 between global polymorphic consts and internal locale representation.
  3382 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  3383 "isatool doc classes" provides a tutorial.
  3384 
  3385 * Generic code generator framework allows to generate executable
  3386 code for ML and Haskell (including Isabelle classes).  A short usage
  3387 sketch:
  3388 
  3389     internal compilation:
  3390         export_code <list of constants (term syntax)> in SML
  3391     writing SML code to a file:
  3392         export_code <list of constants (term syntax)> in SML <filename>
  3393     writing OCaml code to a file:
  3394         export_code <list of constants (term syntax)> in OCaml <filename>
  3395     writing Haskell code to a bunch of files:
  3396         export_code <list of constants (term syntax)> in Haskell <filename>
  3397 
  3398     evaluating closed propositions to True/False using code generation:
  3399         method ``eval''
  3400 
  3401 Reasonable default setup of framework in HOL.
  3402 
  3403 Theorem attributs for selecting and transforming function equations theorems:
  3404 
  3405     [code fun]:        select a theorem as function equation for a specific constant
  3406     [code fun del]:    deselect a theorem as function equation for a specific constant
  3407     [code inline]:     select an equation theorem for unfolding (inlining) in place
  3408     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  3409 
  3410 User-defined serializations (target in {SML, OCaml, Haskell}):
  3411 
  3412     code_const <and-list of constants (term syntax)>
  3413       {(target) <and-list of const target syntax>}+
  3414 
  3415     code_type <and-list of type constructors>
  3416       {(target) <and-list of type target syntax>}+
  3417 
  3418     code_instance <and-list of instances>
  3419       {(target)}+
  3420         where instance ::= <type constructor> :: <class>
  3421 
  3422     code_class <and_list of classes>
  3423       {(target) <and-list of class target syntax>}+
  3424         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  3425 
  3426 code_instance and code_class only are effective to target Haskell.
  3427 
  3428 For example usage see src/HOL/ex/Codegenerator.thy and
  3429 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  3430 generation from Isabelle/HOL theories is available via "isatool doc
  3431 codegen".
  3432 
  3433 * Code generator: consts in 'consts_code' Isar commands are now
  3434 referred to by usual term syntax (including optional type
  3435 annotations).
  3436 
  3437 * Command 'no_translations' removes translation rules from theory
  3438 syntax.
  3439 
  3440 * Overloaded definitions are now actually checked for acyclic
  3441 dependencies.  The overloading scheme is slightly more general than
  3442 that of Haskell98, although Isabelle does not demand an exact
  3443 correspondence to type class and instance declarations.
  3444 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  3445 exotic versions of overloading -- at the discretion of the user!
  3446 
  3447 Polymorphic constants are represented via type arguments, i.e. the
  3448 instantiation that matches an instance against the most general
  3449 declaration given in the signature.  For example, with the declaration
  3450 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  3451 as c(nat).  Overloading is essentially simultaneous structural
  3452 recursion over such type arguments.  Incomplete specification patterns
  3453 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  3454 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  3455 Command 'print_theory' outputs the normalized system of recursive
  3456 equations, see section "definitions".
  3457 
  3458 * Configuration options are maintained within the theory or proof
  3459 context (with name and type bool/int/string), providing a very simple
  3460 interface to a poor-man's version of general context data.  Tools may
  3461 declare options in ML (e.g. using Attrib.config_int) and then refer to
  3462 these values using Config.get etc.  Users may change options via an
  3463 associated attribute of the same name.  This form of context
  3464 declaration works particularly well with commands 'declare' or
  3465 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  3466 very easy to avoid global references, which would not observe Isar
  3467 toplevel undo/redo and fail to work with multithreading.
  3468 
  3469 Various global ML references of Pure and HOL have been turned into
  3470 configuration options:
  3471 
  3472   Unify.search_bound		unify_search_bound
  3473   Unify.trace_bound		unify_trace_bound
  3474   Unify.trace_simp		unify_trace_simp
  3475   Unify.trace_types		unify_trace_types
  3476   Simplifier.simp_depth_limit	simp_depth_limit
  3477   Blast.depth_limit		blast_depth_limit
  3478   DatatypeProp.dtK		datatype_distinctness_limit
  3479   fast_arith_neq_limit  	fast_arith_neq_limit
  3480   fast_arith_split_limit	fast_arith_split_limit
  3481 
  3482 * Named collections of theorems may be easily installed as context
  3483 data using the functor NamedThmsFun (see also
  3484 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  3485 attributes; there is also a toplevel print command.  This facility is
  3486 just a common case of general context data, which is the preferred way
  3487 for anything more complex than just a list of facts in canonical
  3488 order.
  3489 
  3490 * Isar: command 'declaration' augments a local theory by generic
  3491 declaration functions written in ML.  This enables arbitrary content
  3492 being added to the context, depending on a morphism that tells the
  3493 difference of the original declaration context wrt. the application
  3494 context encountered later on.
  3495 
  3496 * Isar: proper interfaces for simplification procedures.  Command
  3497 'simproc_setup' declares named simprocs (with match patterns, and body
  3498 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  3499 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  3500 
  3501 * Isar: an extra pair of brackets around attribute declarations
  3502 abbreviates a theorem reference involving an internal dummy fact,
  3503 which will be ignored later --- only the effect of the attribute on
  3504 the background context will persist.  This form of in-place
  3505 declarations is particularly useful with commands like 'declare' and
  3506 'using', for example ``have A using [[simproc a]] by simp''.
  3507 
  3508 * Isar: method "assumption" (and implicit closing of subproofs) now
  3509 takes simple non-atomic goal assumptions into account: after applying
  3510 an assumption as a rule the resulting subgoals are solved by atomic
  3511 assumption steps.  This is particularly useful to finish 'obtain'
  3512 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  3513 without referring to the original premise "!!x. P x ==> thesis" in the
  3514 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  3515 more permissive.
  3516 
  3517 * Isar: implicit use of prems from the Isar proof context is
  3518 considered a legacy feature.  Common applications like ``have A .''
  3519 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  3520 referencing facts explicitly here improves readability and
  3521 maintainability of proof texts.
  3522 
  3523 * Isar: improper proof element 'guess' is like 'obtain', but derives
  3524 the obtained context from the course of reasoning!  For example:
  3525 
  3526   assume "EX x y. A x & B y"   -- "any previous fact"
  3527   then guess x and y by clarify
  3528 
  3529 This technique is potentially adventurous, depending on the facts and
  3530 proof tools being involved here.
  3531 
  3532 * Isar: known facts from the proof context may be specified as literal
  3533 propositions, using ASCII back-quote syntax.  This works wherever
  3534 named facts used to be allowed so far, in proof commands, proof
  3535 methods, attributes etc.  Literal facts are retrieved from the context
  3536 according to unification of type and term parameters.  For example,
  3537 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  3538 theorems in the current context, then these are valid literal facts:
  3539 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  3540 
  3541 There is also a proof method "fact" which does the same composition
  3542 for explicit goal states, e.g. the following proof texts coincide with
  3543 certain special cases of literal facts:
  3544 
  3545   have "A" by fact                 ==  note `A`
  3546   have "A ==> B" by fact           ==  note `A ==> B`
  3547   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  3548   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  3549 
  3550 * Isar: ":" (colon) is no longer a symbolic identifier character in
  3551 outer syntax.  Thus symbolic identifiers may be used without
  3552 additional white space in declarations like this: ``assume *: A''.
  3553 
  3554 * Isar: 'print_facts' prints all local facts of the current context,
  3555 both named and unnamed ones.
  3556 
  3557 * Isar: 'def' now admits simultaneous definitions, e.g.:
  3558 
  3559   def x == "t" and y == "u"
  3560 
  3561 * Isar: added command 'unfolding', which is structurally similar to
  3562 'using', but affects both the goal state and facts by unfolding given
  3563 rewrite rules.  Thus many occurrences of the 'unfold' method or
  3564 'unfolded' attribute may be replaced by first-class proof text.
  3565 
  3566 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  3567 and command 'unfolding' now all support object-level equalities
  3568 (potentially conditional).  The underlying notion of rewrite rule is
  3569 analogous to the 'rule_format' attribute, but *not* that of the
  3570 Simplifier (which is usually more generous).
  3571 
  3572 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  3573 premises of a theorem by n. Useful in conjunction with drule.
  3574 
  3575 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  3576 method expression within a sandbox consisting of the first N
  3577 sub-goals, which need to exist.  For example, ``simp_all [3]''
  3578 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  3579 simplifies all new goals that emerge from applying rule foo to the
  3580 originally first one.
  3581 
  3582 * Isar: schematic goals are no longer restricted to higher-order
  3583 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  3584 expected.
  3585 
  3586 * Isar: the conclusion of a long theorem statement is now either
  3587 'shows' (a simultaneous conjunction, as before), or 'obtains'
  3588 (essentially a disjunction of cases with local parameters and
  3589 assumptions).  The latter allows to express general elimination rules
  3590 adequately; in this notation common elimination rules look like this:
  3591 
  3592   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  3593     assumes "EX x. P x"
  3594     obtains x where "P x"
  3595 
  3596   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  3597     assumes "A & B"
  3598     obtains A and B
  3599 
  3600   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  3601     assumes "A | B"
  3602     obtains
  3603       A
  3604     | B
  3605 
  3606 The subsequent classical rules even refer to the formal "thesis"
  3607 explicitly:
  3608 
  3609   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  3610     obtains "~ thesis"
  3611 
  3612   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  3613     obtains "thesis ==> something"
  3614 
  3615 The actual proof of an 'obtains' statement is analogous to that of the
  3616 Isar proof element 'obtain', only that there may be several cases.
  3617 Optional case names may be specified in parentheses; these will be
  3618 available both in the present proof and as annotations in the
  3619 resulting rule, for later use with the 'cases' method (cf. attribute
  3620 case_names).
  3621 
  3622 * Isar: the assumptions of a long theorem statement are available as
  3623 "assms" fact in the proof context.  This is more appropriate than the
  3624 (historical) "prems", which refers to all assumptions of the current
  3625 context, including those from the target locale, proof body etc.
  3626 
  3627 * Isar: 'print_statement' prints theorems from the current theory or
  3628 proof context in long statement form, according to the syntax of a
  3629 top-level lemma.
  3630 
  3631 * Isar: 'obtain' takes an optional case name for the local context
  3632 introduction rule (default "that").
  3633 
  3634 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  3635 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  3636 to occur.
  3637 
  3638 * Pure: syntax "CONST name" produces a fully internalized constant
  3639 according to the current context.  This is particularly useful for
  3640 syntax translations that should refer to internal constant
  3641 representations independently of name spaces.
  3642 
  3643 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  3644 instead of "FOO ". This allows multiple binder declarations to coexist
  3645 in the same context.  INCOMPATIBILITY.
  3646 
  3647 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  3648 primitive that also works in a locale context (both for constants and
  3649 fixed variables). Type declaration and internal syntactic representation
  3650 of given constants retrieved from the context. Likewise, the
  3651 'no_notation' command allows to remove given syntax annotations from the
  3652 current context.
  3653 
  3654 * Isar/locales: new derived specification elements 'axiomatization',
  3655 'definition', 'abbreviation', which support type-inference, admit
  3656 object-level specifications (equality, equivalence).  See also the
  3657 isar-ref manual.  Examples:
  3658 
  3659   axiomatization
  3660     eq  (infix "===" 50) where
  3661     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  3662 
  3663   definition "f x y = x + y + 1"
  3664   definition g where "g x = f x x"
  3665 
  3666   abbreviation
  3667     neq  (infix "=!=" 50) where
  3668     "x =!= y == ~ (x === y)"
  3669 
  3670 These specifications may be also used in a locale context.  Then the
  3671 constants being introduced depend on certain fixed parameters, and the
  3672 constant name is qualified by the locale base name.  An internal
  3673 abbreviation takes care for convenient input and output, making the
  3674 parameters implicit and using the original short name.  See also
  3675 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  3676 entities from a monomorphic theory.
  3677 
  3678 Presently, abbreviations are only available 'in' a target locale, but
  3679 not inherited by general import expressions.  Also note that
  3680 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  3681 'translations' in common applications.  The "no_abbrevs" print mode
  3682 prevents folding of abbreviations in term output.
  3683 
  3684 Concrete syntax is attached to specified constants in internal form,
  3685 independently of name spaces.  The parse tree representation is
  3686 slightly different -- use 'notation' instead of raw 'syntax', and
  3687 'translations' with explicit "CONST" markup to accommodate this.
  3688 
  3689 * Pure/Isar: unified syntax for new-style specification mechanisms
  3690 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  3691 full type inference and dummy patterns ("_").  For example:
  3692 
  3693   definition "K x _ = x"
  3694 
  3695   inductive conj for A B
  3696   where "A ==> B ==> conj A B"
  3697 
  3698 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  3699 the current context.  Print mode "no_abbrevs" prevents inversion of
  3700 abbreviations on output.
  3701 
  3702 * Isar/locales: improved parameter handling: use of locales "var" and
  3703 "struct" no longer necessary; - parameter renamings are no longer
  3704 required to be injective.  For example, this allows to define
  3705 endomorphisms as locale endom = homom mult mult h.
  3706 
  3707 * Isar/locales: changed the way locales with predicates are defined.
  3708 Instead of accumulating the specification, the imported expression is
  3709 now an interpretation.  INCOMPATIBILITY: different normal form of
  3710 locale expressions.  In particular, in interpretations of locales with
  3711 predicates, goals repesenting already interpreted fragments are not
  3712 removed automatically.  Use methods `intro_locales' and
  3713 `unfold_locales'; see below.
  3714 
  3715 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  3716 provide backward reasoning on locales predicates.  The methods are
  3717 aware of interpretations and discharge corresponding goals.
  3718 `intro_locales' is less aggressive then `unfold_locales' and does not
  3719 unfold predicates to assumptions.
  3720 
  3721 * Isar/locales: the order in which locale fragments are accumulated
  3722 has changed.  This enables to override declarations from fragments due
  3723 to interpretations -- for example, unwanted simp rules.
  3724 
  3725 * Isar/locales: interpretation in theories and proof contexts has been
  3726 extended.  One may now specify (and prove) equations, which are
  3727 unfolded in interpreted theorems.  This is useful for replacing
  3728 defined concepts (constants depending on locale parameters) by
  3729 concepts already existing in the target context.  Example:
  3730 
  3731   interpretation partial_order ["op <= :: [int, int] => bool"]
  3732     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3733 
  3734 Typically, the constant `partial_order.less' is created by a
  3735 definition specification element in the context of locale
  3736 partial_order.
  3737 
  3738 * Method "induct": improved internal context management to support
  3739 local fixes and defines on-the-fly. Thus explicit meta-level
  3740 connectives !!  and ==> are rarely required anymore in inductive goals
  3741 (using object-logic connectives for this purpose has been long
  3742 obsolete anyway). Common proof patterns are explained in
  3743 src/HOL/Induct/Common_Patterns.thy, see also
  3744 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3745 examples.
  3746 
  3747 * Method "induct": improved handling of simultaneous goals. Instead of
  3748 introducing object-level conjunction, the statement is now split into
  3749 several conclusions, while the corresponding symbolic cases are nested
  3750 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3751 see src/HOL/Induct/Common_Patterns.thy, for example.
  3752 
  3753 * Method "induct": mutual induction rules are now specified as a list
  3754 of rule sharing the same induction cases. HOL packages usually provide
  3755 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3756 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3757 mutual induction rules differently, i.e. like this:
  3758 
  3759   (induct rule: foo_bar.inducts)
  3760   (induct set: foo bar)
  3761   (induct pred: foo bar)
  3762   (induct type: foo bar)
  3763 
  3764 The ML function ProjectRule.projections turns old-style rules into the
  3765 new format.
  3766 
  3767 * Method "coinduct": dual of induction, see
  3768 src/HOL/Library/Coinductive_List.thy for various examples.
  3769 
  3770 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3771 considered a legacy feature.
  3772 
  3773 * Attribute "symmetric" produces result with standardized schematic
  3774 variables (index 0).  Potential INCOMPATIBILITY.
  3775 
  3776 * Simplifier: by default the simplifier trace only shows top level
  3777 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3778 default. Thus there is less danger of being flooded by the trace. The
  3779 trace indicates where parts have been suppressed.
  3780   
  3781 * Provers/classical: removed obsolete classical version of elim_format
  3782 attribute; classical elim/dest rules are now treated uniformly when
  3783 manipulating the claset.
  3784 
  3785 * Provers/classical: stricter checks to ensure that supplied intro,
  3786 dest and elim rules are well-formed; dest and elim rules must have at
  3787 least one premise.
  3788 
  3789 * Provers/classical: attributes dest/elim/intro take an optional
  3790 weight argument for the rule (just as the Pure versions).  Weights are
  3791 ignored by automated tools, but determine the search order of single
  3792 rule steps.
  3793 
  3794 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3795 where the body does not mention the bound variable.  Note that dummy
  3796 patterns implicitly depend on their context of bounds, which makes
  3797 "{_. _}" match any set comprehension as expected.  Potential
  3798 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3799 constant "_idtdummy" in the binding position.
  3800 
  3801 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3802 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3803 for example "A -> B" => "Pi A (%_. B)".
  3804 
  3805 * Pure: 'class_deps' command visualizes the subclass relation, using
  3806 the graph browser tool.
  3807 
  3808 * Pure: 'print_theory' now suppresses certain internal declarations by
  3809 default; use '!' option for full details.
  3810 
  3811 
  3812 *** HOL ***
  3813 
  3814 * Method "metis" proves goals by applying the Metis general-purpose
  3815 resolution prover (see also http://gilith.com/software/metis/).
  3816 Examples are in the directory MetisExamples.  WARNING: the
  3817 Isabelle/HOL-Metis integration does not yet work properly with
  3818 multi-threading.
  3819   
  3820 * Command 'sledgehammer' invokes external automatic theorem provers as
  3821 background processes.  It generates calls to the "metis" method if
  3822 successful. These can be pasted into the proof.  Users do not have to
  3823 wait for the automatic provers to return.  WARNING: does not really
  3824 work with multi-threading.
  3825 
  3826 * New "auto_quickcheck" feature tests outermost goal statements for
  3827 potential counter-examples.  Controlled by ML references
  3828 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3829 5000 milliseconds).  Fails silently if statements is outside of
  3830 executable fragment, or any other codgenerator problem occurs.
  3831 
  3832 * New constant "undefined" with axiom "undefined x = undefined".
  3833 
  3834 * Added class "HOL.eq", allowing for code generation with polymorphic
  3835 equality.
  3836 
  3837 * Some renaming of class constants due to canonical name prefixing in
  3838 the new 'class' package:
  3839 
  3840     HOL.abs ~> HOL.abs_class.abs
  3841     HOL.divide ~> HOL.divide_class.divide
  3842     0 ~> HOL.zero_class.zero
  3843     1 ~> HOL.one_class.one
  3844     op + ~> HOL.plus_class.plus
  3845     op - ~> HOL.minus_class.minus
  3846     uminus ~> HOL.minus_class.uminus
  3847     op * ~> HOL.times_class.times
  3848     op < ~> HOL.ord_class.less
  3849     op <= > HOL.ord_class.less_eq
  3850     Nat.power ~> Power.power_class.power
  3851     Nat.size ~> Nat.size_class.size
  3852     Numeral.number_of ~> Numeral.number_class.number_of
  3853     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3854     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3855     Orderings.min ~> Orderings.ord_class.min
  3856     Orderings.max ~> Orderings.ord_class.max
  3857     Divides.op div ~> Divides.div_class.div
  3858     Divides.op mod ~> Divides.div_class.mod
  3859     Divides.op dvd ~> Divides.div_class.dvd
  3860 
  3861 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3862 
  3863 a) User-defined constants using any of the names "plus", "minus",
  3864 "times", "less" or "less_eq". The standard syntax translations for
  3865 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3866 names.
  3867 
  3868 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3869 INCOMPATIBILITY: use more specific names.
  3870 
  3871 c) Permutative equations (e.g. "a + b = b + a")
  3872 Since the change of names also changes the order of terms, permutative
  3873 rewrite rules may get applied in a different order. Experience shows
  3874 that this is rarely the case (only two adaptions in the whole Isabelle
  3875 distribution).  INCOMPATIBILITY: rewrite proofs
  3876 
  3877 d) ML code directly refering to constant names
  3878 This in general only affects hand-written proof tactics, simprocs and
  3879 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3880 Consider using @{const_name} antiquotation.
  3881 
  3882 * New class "default" with associated constant "default".
  3883 
  3884 * Function "sgn" is now overloaded and available on int, real, complex
  3885 (and other numeric types), using class "sgn".  Two possible defs of
  3886 sgn are given as equational assumptions in the classes sgn_if and
  3887 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3888 INCOMPATIBILITY.
  3889 
  3890 * Locale "partial_order" now unified with class "order" (cf. theory
  3891 Orderings), added parameter "less".  INCOMPATIBILITY.
  3892 
  3893 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3894 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3895 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3896 
  3897 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3898 changed order of proof goals in instance proofs.
  3899 
  3900 * The transitivity reasoner for partial and linear orders is set up
  3901 for classes "order" and "linorder".  Instances of the reasoner are available
  3902 in all contexts importing or interpreting the corresponding locales.
  3903 Method "order" invokes the reasoner separately; the reasoner
  3904 is also integrated with the Simplifier as a solver.  Diagnostic
  3905 command 'print_orders' shows the available instances of the reasoner
  3906 in the current context.
  3907 
  3908 * Localized monotonicity predicate in theory "Orderings"; integrated
  3909 lemmas max_of_mono and min_of_mono with this predicate.
  3910 INCOMPATIBILITY.
  3911 
  3912 * Formulation of theorem "dense" changed slightly due to integration
  3913 with new class dense_linear_order.
  3914 
  3915 * Uniform lattice theory development in HOL.
  3916 
  3917     constants "meet" and "join" now named "inf" and "sup"
  3918     constant "Meet" now named "Inf"
  3919 
  3920     classes "meet_semilorder" and "join_semilorder" now named
  3921       "lower_semilattice" and "upper_semilattice"
  3922     class "lorder" now named "lattice"
  3923     class "comp_lat" now named "complete_lattice"
  3924 
  3925     Instantiation of lattice classes allows explicit definitions
  3926     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3927 
  3928   INCOMPATIBILITY.  Theorem renames:
  3929 
  3930     meet_left_le            ~> inf_le1
  3931     meet_right_le           ~> inf_le2
  3932     join_left_le            ~> sup_ge1
  3933     join_right_le           ~> sup_ge2
  3934     meet_join_le            ~> inf_sup_ord
  3935     le_meetI                ~> le_infI
  3936     join_leI                ~> le_supI
  3937     le_meet                 ~> le_inf_iff
  3938     le_join                 ~> ge_sup_conv
  3939     meet_idempotent         ~> inf_idem
  3940     join_idempotent         ~> sup_idem
  3941     meet_comm               ~> inf_commute
  3942     join_comm               ~> sup_commute
  3943     meet_leI1               ~> le_infI1
  3944     meet_leI2               ~> le_infI2
  3945     le_joinI1               ~> le_supI1
  3946     le_joinI2               ~> le_supI2
  3947     meet_assoc              ~> inf_assoc
  3948     join_assoc              ~> sup_assoc
  3949     meet_left_comm          ~> inf_left_commute
  3950     meet_left_idempotent    ~> inf_left_idem
  3951     join_left_comm          ~> sup_left_commute
  3952     join_left_idempotent    ~> sup_left_idem
  3953     meet_aci                ~> inf_aci
  3954     join_aci                ~> sup_aci
  3955     le_def_meet             ~> le_iff_inf
  3956     le_def_join             ~> le_iff_sup
  3957     join_absorp2            ~> sup_absorb2
  3958     join_absorp1            ~> sup_absorb1
  3959     meet_absorp1            ~> inf_absorb1
  3960     meet_absorp2            ~> inf_absorb2
  3961     meet_join_absorp        ~> inf_sup_absorb
  3962     join_meet_absorp        ~> sup_inf_absorb
  3963     distrib_join_le         ~> distrib_sup_le
  3964     distrib_meet_le         ~> distrib_inf_le
  3965 
  3966     add_meet_distrib_left   ~> add_inf_distrib_left
  3967     add_join_distrib_left   ~> add_sup_distrib_left
  3968     is_join_neg_meet        ~> is_join_neg_inf
  3969     is_meet_neg_join        ~> is_meet_neg_sup
  3970     add_meet_distrib_right  ~> add_inf_distrib_right
  3971     add_join_distrib_right  ~> add_sup_distrib_right
  3972     add_meet_join_distribs  ~> add_sup_inf_distribs
  3973     join_eq_neg_meet        ~> sup_eq_neg_inf
  3974     meet_eq_neg_join        ~> inf_eq_neg_sup
  3975     add_eq_meet_join        ~> add_eq_inf_sup
  3976     meet_0_imp_0            ~> inf_0_imp_0
  3977     join_0_imp_0            ~> sup_0_imp_0
  3978     meet_0_eq_0             ~> inf_0_eq_0
  3979     join_0_eq_0             ~> sup_0_eq_0
  3980     neg_meet_eq_join        ~> neg_inf_eq_sup
  3981     neg_join_eq_meet        ~> neg_sup_eq_inf
  3982     join_eq_if              ~> sup_eq_if
  3983 
  3984     mono_meet               ~> mono_inf
  3985     mono_join               ~> mono_sup
  3986     meet_bool_eq            ~> inf_bool_eq
  3987     join_bool_eq            ~> sup_bool_eq
  3988     meet_fun_eq             ~> inf_fun_eq
  3989     join_fun_eq             ~> sup_fun_eq
  3990     meet_set_eq             ~> inf_set_eq
  3991     join_set_eq             ~> sup_set_eq
  3992     meet1_iff               ~> inf1_iff
  3993     meet2_iff               ~> inf2_iff
  3994     meet1I                  ~> inf1I
  3995     meet2I                  ~> inf2I
  3996     meet1D1                 ~> inf1D1
  3997     meet2D1                 ~> inf2D1
  3998     meet1D2                 ~> inf1D2
  3999     meet2D2                 ~> inf2D2
  4000     meet1E                  ~> inf1E
  4001     meet2E                  ~> inf2E
  4002     join1_iff               ~> sup1_iff
  4003     join2_iff               ~> sup2_iff
  4004     join1I1                 ~> sup1I1
  4005     join2I1                 ~> sup2I1
  4006     join1I1                 ~> sup1I1
  4007     join2I2                 ~> sup1I2
  4008     join1CI                 ~> sup1CI
  4009     join2CI                 ~> sup2CI
  4010     join1E                  ~> sup1E
  4011     join2E                  ~> sup2E
  4012 
  4013     is_meet_Meet            ~> is_meet_Inf
  4014     Meet_bool_def           ~> Inf_bool_def
  4015     Meet_fun_def            ~> Inf_fun_def
  4016     Meet_greatest           ~> Inf_greatest
  4017     Meet_lower              ~> Inf_lower
  4018     Meet_set_def            ~> Inf_set_def
  4019 
  4020     Sup_def                 ~> Sup_Inf
  4021     Sup_bool_eq             ~> Sup_bool_def
  4022     Sup_fun_eq              ~> Sup_fun_def
  4023     Sup_set_eq              ~> Sup_set_def
  4024 
  4025     listsp_meetI            ~> listsp_infI
  4026     listsp_meet_eq          ~> listsp_inf_eq
  4027 
  4028     meet_min                ~> inf_min
  4029     join_max                ~> sup_max
  4030 
  4031 * Added syntactic class "size"; overloaded constant "size" now has
  4032 type "'a::size ==> bool"
  4033 
  4034 * Internal reorganisation of `size' of datatypes: size theorems
  4035 "foo.size" are no longer subsumed by "foo.simps" (but are still
  4036 simplification rules by default!); theorems "prod.size" now named
  4037 "*.size".
  4038 
  4039 * Class "div" now inherits from class "times" rather than "type".
  4040 INCOMPATIBILITY.
  4041 
  4042 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  4043 Linorder etc.  have disappeared; operations defined in terms of
  4044 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  4045 
  4046 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  4047 
  4048 * HOL-Word: New extensive library and type for generic, fixed size
  4049 machine words, with arithemtic, bit-wise, shifting and rotating
  4050 operations, reflection into int, nat, and bool lists, automation for
  4051 linear arithmetic (by automatic reflection into nat or int), including
  4052 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  4053 arithmetic type classes, supporting automatic simplification of
  4054 numerals on all operations.
  4055 
  4056 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  4057 
  4058 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  4059 
  4060 * Code generator library theories:
  4061   - Code_Integer represents HOL integers by big integer literals in target
  4062     languages.
  4063   - Code_Char represents HOL characters by character literals in target
  4064     languages.
  4065   - Code_Char_chr like Code_Char, but also offers treatment of character
  4066     codes; includes Code_Integer.
  4067   - Executable_Set allows to generate code for finite sets using lists.
  4068   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  4069     denominator).
  4070   - Executable_Real implements a subset of real numbers, namly those
  4071     representable by rational numbers.
  4072   - Efficient_Nat implements natural numbers by integers, which in general will
  4073     result in higher efficency; pattern matching with 0/Suc is eliminated;
  4074     includes Code_Integer.
  4075   - Code_Index provides an additional datatype index which is mapped to
  4076     target-language built-in integers.
  4077   - Code_Message provides an additional datatype message_string which is isomorphic to
  4078     strings; messages are mapped to target-language strings.
  4079 
  4080 * New package for inductive predicates
  4081 
  4082   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  4083 
  4084     inductive
  4085       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4086       for z_1 :: U_1 and ... and z_n :: U_m
  4087     where
  4088       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4089     | ...
  4090 
  4091   with full support for type-inference, rather than
  4092 
  4093     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4094 
  4095     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4096     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4097 
  4098     inductive "s z_1 ... z_m"
  4099     intros
  4100       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4101       ...
  4102 
  4103   For backward compatibility, there is a wrapper allowing inductive
  4104   sets to be defined with the new package via
  4105 
  4106     inductive_set
  4107       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4108       for z_1 :: U_1 and ... and z_n :: U_m
  4109     where
  4110       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4111     | ...
  4112 
  4113   or
  4114 
  4115     inductive_set
  4116       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4117       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4118       for z_1 :: U_1 and ... and z_n :: U_m
  4119     where
  4120       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4121     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4122     | ...
  4123 
  4124   if the additional syntax "p ..." is required.
  4125 
  4126   Numerous examples can be found in the subdirectories src/HOL/Auth,
  4127   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  4128 
  4129   INCOMPATIBILITIES:
  4130 
  4131   - Since declaration and definition of inductive sets or predicates
  4132     is no longer separated, abbreviations involving the newly
  4133     introduced sets or predicates must be specified together with the
  4134     introduction rules after the 'where' keyword (see above), rather
  4135     than before the actual inductive definition.
  4136 
  4137   - The variables in induction and elimination rules are now
  4138     quantified in the order of their occurrence in the introduction
  4139     rules, rather than in alphabetical order. Since this may break
  4140     some proofs, these proofs either have to be repaired, e.g. by
  4141     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  4142     statements of the form
  4143 
  4144       case (rule_i a_i_1 ... a_i_{k_i})
  4145 
  4146     or the old order of quantification has to be restored by explicitly adding
  4147     meta-level quantifiers in the introduction rules, i.e.
  4148 
  4149       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  4150 
  4151   - The format of the elimination rules is now
  4152 
  4153       p z_1 ... z_m x_1 ... x_n ==>
  4154         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4155         ==> ... ==> P
  4156 
  4157     for predicates and
  4158 
  4159       (x_1, ..., x_n) : s z_1 ... z_m ==>
  4160         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4161         ==> ... ==> P
  4162 
  4163     for sets rather than
  4164 
  4165       x : s z_1 ... z_m ==>
  4166         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  4167         ==> ... ==> P
  4168 
  4169     This may require terms in goals to be expanded to n-tuples
  4170     (e.g. using case_tac or simplification with the split_paired_all
  4171     rule) before the above elimination rule is applicable.
  4172 
  4173   - The elimination or case analysis rules for (mutually) inductive
  4174     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  4175     list of rules "p_1_..._p_k.elims" is no longer available.
  4176 
  4177 * New package "function"/"fun" for general recursive functions,
  4178 supporting mutual and nested recursion, definitions in local contexts,
  4179 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  4180 for small examples, and the separate tutorial on the function
  4181 package. The old recdef "package" is still available as before, but
  4182 users are encouraged to use the new package.
  4183 
  4184 * Method "lexicographic_order" automatically synthesizes termination
  4185 relations as lexicographic combinations of size measures. 
  4186 
  4187 * Case-expressions allow arbitrary constructor-patterns (including
  4188 "_") and take their order into account, like in functional
  4189 programming.  Internally, this is translated into nested
  4190 case-expressions; missing cases are added and mapped to the predefined
  4191 constant "undefined". In complicated cases printing may no longer show
  4192 the original input but the internal form. Lambda-abstractions allow
  4193 the same form of pattern matching: "% pat1 => e1 | ..." is an
  4194 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  4195 variable.
  4196 
  4197 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  4198 is an abbreviation for "of_nat :: nat => int". The simplification
  4199 rules for "of_nat" have been changed to work like "int" did
  4200 previously.  Potential INCOMPATIBILITY:
  4201   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  4202   - of_nat_diff and of_nat_mult are no longer default simp rules
  4203 
  4204 * Method "algebra" solves polynomial equations over (semi)rings using
  4205 Groebner bases. The (semi)ring structure is defined by locales and the
  4206 tool setup depends on that generic context. Installing the method for
  4207 a specific type involves instantiating the locale and possibly adding
  4208 declarations for computation on the coefficients.  The method is
  4209 already instantiated for natural numbers and for the axiomatic class
  4210 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  4211 CALCULEMUS 2007 for the general principles underlying this
  4212 architecture of context-aware proof-tools.
  4213 
  4214 * Method "ferrack" implements quantifier elimination over
  4215 special-purpose dense linear orders using locales (analogous to
  4216 "algebra"). The method is already installed for class
  4217 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  4218 rat, etc.
  4219 
  4220 * Former constant "List.op @" now named "List.append".  Use ML
  4221 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  4222 circumvent possible incompatibilities when working on ML level.
  4223 
  4224 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  4225 
  4226 * New function listsum :: 'a list => 'a for arbitrary monoids.
  4227 Special syntax: "SUM x <- xs. f x" (and latex variants)
  4228 
  4229 * New syntax for Haskell-like list comprehension (input only), eg.
  4230 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  4231 
  4232 * The special syntax for function "filter" has changed from [x :
  4233 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  4234 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  4235 
  4236 * [a..b] is now defined for arbitrary linear orders.  It used to be
  4237 defined on nat only, as an abbreviation for [a..<Suc b]
  4238 INCOMPATIBILITY.
  4239 
  4240 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  4241 
  4242 * New functions "sorted" and "sort" in src/HOL/List.thy.
  4243 
  4244 * New lemma collection field_simps (an extension of ring_simps) for
  4245 manipulating (in)equations involving division. Multiplies with all
  4246 denominators that can be proved to be non-zero (in equations) or
  4247 positive/negative (in inequations).
  4248 
  4249 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  4250 have been improved and renamed to ring_simps, group_simps and
  4251 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  4252 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  4253 
  4254 * Theory Library/Commutative_Ring: switched from recdef to function
  4255 package; constants add, mul, pow now curried.  Infix syntax for
  4256 algebraic operations.
  4257 
  4258 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  4259 INCOMPATIBILITY.
  4260 
  4261 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  4262 INCOMPATIBILITY.
  4263 
  4264 * HOL/records: generalised field-update to take a function on the
  4265 field rather than the new value: r(|A := x|) is translated to A_update
  4266 (K x) r The K-combinator that is internally used is called K_record.
  4267 INCOMPATIBILITY: Usage of the plain update functions has to be
  4268 adapted.
  4269  
  4270 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  4271 * x = 0, which are required for a semiring.  Richer structures do not
  4272 inherit from semiring_0 anymore, because this property is a theorem
  4273 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  4274 there is more to prove, but this is mostly trivial.
  4275 
  4276 * Class "recpower" is generalized to arbitrary monoids, not just
  4277 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  4278 commutativity or semiring properties additionally.
  4279 
  4280 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  4281 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  4282 better use 'abbreviation'.
  4283 
  4284 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  4285 
  4286 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  4287 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  4288 significant changes for setting up numeral syntax for types:
  4289   - New constants Numeral.pred and Numeral.succ instead
  4290       of former Numeral.bin_pred and Numeral.bin_succ.
  4291   - Use integer operations instead of bin_add, bin_mult and so on.
  4292   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  4293   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  4294 
  4295 See src/HOL/Integ/IntArith.thy for an example setup.
  4296 
  4297 * Command 'normal_form' computes the normal form of a term that may
  4298 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  4299 produces ``[b, c, a]'' (without proof).  This command is suitable for
  4300 heavy-duty computations because the functions are compiled to ML
  4301 first.  Correspondingly, a method "normalization" is provided.  See
  4302 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  4303 
  4304 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  4305 25 like -->); output depends on the "iff" print_mode, the default is
  4306 "A = B" (with priority 50).
  4307 
  4308 * Relations less (<) and less_eq (<=) are also available on type bool.
  4309 Modified syntax to disallow nesting without explicit parentheses,
  4310 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  4311 INCOMPATIBILITY.
  4312 
  4313 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  4314 
  4315 * Relation composition operator "op O" now has precedence 75 and binds
  4316 stronger than union and intersection. INCOMPATIBILITY.
  4317 
  4318 * The old set interval syntax "{m..n(}" (and relatives) has been
  4319 removed.  Use "{m..<n}" (and relatives) instead.
  4320 
  4321 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  4322 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  4323 ``declare [[simproc del: neq]]''.
  4324 
  4325 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  4326 True/False.
  4327 
  4328 * Theorem Cons_eq_map_conv no longer declared as "simp".
  4329 
  4330 * Theorem setsum_mult renamed to setsum_right_distrib.
  4331 
  4332 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  4333 ``rule'' method.
  4334 
  4335 * Reimplemented methods "sat" and "satx", with several improvements:
  4336 goals no longer need to be stated as "<prems> ==> False", equivalences
  4337 (i.e. "=" on type bool) are handled, variable names of the form
  4338 "lit_<n>" are no longer reserved, significant speedup.
  4339 
  4340 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  4341 zChaff is still supported as well.
  4342 
  4343 * 'inductive' and 'datatype': provide projections of mutual rules,
  4344 bundled as foo_bar.inducts;
  4345 
  4346 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  4347 Library.
  4348 
  4349 * Library: moved theory Accessible_Part to main HOL.
  4350 
  4351 * Library: added theory Coinductive_List of potentially infinite lists
  4352 as greatest fixed-point.
  4353 
  4354 * Library: added theory AssocList which implements (finite) maps as
  4355 association lists.
  4356 
  4357 * Method "evaluation" solves goals (i.e. a boolean expression)
  4358 efficiently by compiling it to ML.  The goal is "proved" (via an
  4359 oracle) if it evaluates to True.
  4360 
  4361 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  4362 also when invoked by the simplifier.  This results in the Simplifier
  4363 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  4364 Configuration option fast_arith_split_limit=0 recovers the old
  4365 behavior.
  4366 
  4367 * Support for hex (0x20) and binary (0b1001) numerals.
  4368 
  4369 * New method: reify eqs (t), where eqs are equations for an
  4370 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  4371 parameter, computes a term s::'b and a list xs::'a list and proves the
  4372 theorem I xs s = t. This is also known as reification or quoting. The
  4373 resulting theorem is applied to the subgoal to substitute t with I xs
  4374 s.  If t is omitted, the subgoal itself is reified.
  4375 
  4376 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  4377 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  4378 where f is supposed to be a computable function (in the sense of code
  4379 generattion). The method uses reify to compute s and xs as above then
  4380 applies corr_thm and uses normalization by evaluation to "prove" f s =
  4381 r and finally gets the theorem t = r, which is again applied to the
  4382 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  4383 
  4384 * Reflection: Automatic reification now handels binding, an example is
  4385 available in src/HOL/ex/ReflectionEx.thy
  4386 
  4387 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  4388 command 'statespace' that is similar to 'record', but introduces an
  4389 abstract specification based on the locale infrastructure instead of
  4390 HOL types.  This leads to extra flexibility in composing state spaces,
  4391 in particular multiple inheritance and renaming of components.
  4392 
  4393 
  4394 *** HOL-Complex ***
  4395 
  4396 * Hyperreal: Functions root and sqrt are now defined on negative real
  4397 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  4398 Nonnegativity side conditions have been removed from many lemmas, so
  4399 that more subgoals may now be solved by simplification; potential
  4400 INCOMPATIBILITY.
  4401 
  4402 * Real: new type classes formalize real normed vector spaces and
  4403 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  4404 and norm :: 'a => real.
  4405 
  4406 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  4407 reals into other types. The overloaded constant Reals :: 'a set is now
  4408 defined as range of_real; potential INCOMPATIBILITY.
  4409 
  4410 * Real: proper support for ML code generation, including 'quickcheck'.
  4411 Reals are implemented as arbitrary precision rationals.
  4412 
  4413 * Hyperreal: Several constants that previously worked only for the
  4414 reals have been generalized, so they now work over arbitrary vector
  4415 spaces. Type annotations may need to be added in some cases; potential
  4416 INCOMPATIBILITY.
  4417 
  4418   Infinitesimal  :: ('a::real_normed_vector) star set
  4419   HFinite        :: ('a::real_normed_vector) star set
  4420   HInfinite      :: ('a::real_normed_vector) star set
  4421   approx         :: ('a::real_normed_vector) star => 'a star => bool
  4422   monad          :: ('a::real_normed_vector) star => 'a star set
  4423   galaxy         :: ('a::real_normed_vector) star => 'a star set
  4424   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  4425   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  4426   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  4427   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  4428   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  4429   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  4430   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  4431   sgn            :: 'a::real_normed_vector => 'a
  4432   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  4433 
  4434 * Complex: Some complex-specific constants are now abbreviations for
  4435 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  4436 hnorm.  Other constants have been entirely removed in favor of the
  4437 polymorphic versions (INCOMPATIBILITY):
  4438 
  4439   approx        <-- capprox
  4440   HFinite       <-- CFinite
  4441   HInfinite     <-- CInfinite
  4442   Infinitesimal <-- CInfinitesimal
  4443   monad         <-- cmonad
  4444   galaxy        <-- cgalaxy
  4445   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  4446   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  4447   (ns)deriv     <-- (ns)cderiv
  4448 
  4449 
  4450 *** HOL-Algebra ***
  4451 
  4452 * Formalisation of ideals and the quotient construction over rings.
  4453 
  4454 * Order and lattice theory no longer based on records.
  4455 INCOMPATIBILITY.
  4456 
  4457 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  4458 greatest_closed.  INCOMPATIBILITY.
  4459 
  4460 * Method algebra is now set up via an attribute.  For examples see
  4461 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  4462 of algebraic structures.
  4463 
  4464 * Renamed theory CRing to Ring.
  4465 
  4466 
  4467 *** HOL-Nominal ***
  4468 
  4469 * Substantial, yet incomplete support for nominal datatypes (binding
  4470 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  4471 src/HOL/Nominal/Examples.  Prospective users should consult
  4472 http://isabelle.in.tum.de/nominal/
  4473 
  4474 
  4475 *** ML ***
  4476 
  4477 * ML basics: just one true type int, which coincides with IntInf.int
  4478 (even on SML/NJ).
  4479 
  4480 * ML within Isar: antiquotations allow to embed statically-checked
  4481 formal entities in the source, referring to the context available at
  4482 compile-time.  For example:
  4483 
  4484 ML {* @{sort "{zero,one}"} *}
  4485 ML {* @{typ "'a => 'b"} *}
  4486 ML {* @{term "%x. x"} *}
  4487 ML {* @{prop "x == y"} *}
  4488 ML {* @{ctyp "'a => 'b"} *}
  4489 ML {* @{cterm "%x. x"} *}
  4490 ML {* @{cprop "x == y"} *}
  4491 ML {* @{thm asm_rl} *}
  4492 ML {* @{thms asm_rl} *}
  4493 ML {* @{type_name c} *}
  4494 ML {* @{type_syntax c} *}
  4495 ML {* @{const_name c} *}
  4496 ML {* @{const_syntax c} *}
  4497 ML {* @{context} *}
  4498 ML {* @{theory} *}
  4499 ML {* @{theory Pure} *}
  4500 ML {* @{theory_ref} *}
  4501 ML {* @{theory_ref Pure} *}
  4502 ML {* @{simpset} *}
  4503 ML {* @{claset} *}
  4504 ML {* @{clasimpset} *}
  4505 
  4506 The same works for sources being ``used'' within an Isar context.
  4507 
  4508 * ML in Isar: improved error reporting; extra verbosity with
  4509 ML_Context.trace enabled.
  4510 
  4511 * Pure/General/table.ML: the join operations now works via exceptions
  4512 DUP/SAME instead of type option. This is simpler in simple cases, and
  4513 admits slightly more efficient complex applications.
  4514 
  4515 * Pure: 'advanced' translation functions (parse_translation etc.) now
  4516 use Context.generic instead of just theory.
  4517 
  4518 * Pure: datatype Context.generic joins theory/Proof.context and
  4519 provides some facilities for code that works in either kind of
  4520 context, notably GenericDataFun for uniform theory and proof data.
  4521 
  4522 * Pure: simplified internal attribute type, which is now always
  4523 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  4524 local (Proof.context) attributes have been discontinued, while
  4525 minimizing code duplication. Thm.rule_attribute and
  4526 Thm.declaration_attribute build canonical attributes; see also structure
  4527 Context for further operations on Context.generic, notably
  4528 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  4529 declarations and definitions.
  4530 
  4531 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  4532 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  4533 init only required for impure data. INCOMPATIBILITY: empty really need
  4534 to be empty (no dependencies on theory content!)
  4535 
  4536 * Pure/kernel: consts certification ignores sort constraints given in
  4537 signature declarations. (This information is not relevant to the
  4538 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  4539 potential INCOMPATIBILITY.
  4540 
  4541 * Pure: axiomatic type classes are now purely definitional, with
  4542 explicit proofs of class axioms and super class relations performed
  4543 internally. See Pure/axclass.ML for the main internal interfaces --
  4544 notably AxClass.define_class supercedes AxClass.add_axclass, and
  4545 AxClass.axiomatize_class/classrel/arity supersede
  4546 Sign.add_classes/classrel/arities.
  4547 
  4548 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  4549 global/local versions on theory vs. Proof.context have been
  4550 discontinued; Attrib.syntax and Method.syntax have been adapted
  4551 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  4552 attributes, methods, etc.
  4553 
  4554 * Pure: several functions of signature "... -> theory -> theory * ..."
  4555 have been reoriented to "... -> theory -> ... * theory" in order to
  4556 allow natural usage in combination with the ||>, ||>>, |-> and
  4557 fold_map combinators.
  4558 
  4559 * Pure: official theorem names (closed derivations) and additional
  4560 comments (tags) are now strictly separate.  Name hints -- which are
  4561 maintained as tags -- may be attached any time without affecting the
  4562 derivation.
  4563 
  4564 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  4565 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  4566 achieve the old behaviour.
  4567 
  4568 * Pure: the "Goal" constant is now called "prop", supporting a
  4569 slightly more general idea of ``protecting'' meta-level rule
  4570 statements.
  4571 
  4572 * Pure: Logic.(un)varify only works in a global context, which is now
  4573 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  4574 Logic.legacy_(un)varify as temporary workaround.
  4575 
  4576 * Pure: structure Name provides scalable operations for generating
  4577 internal variable names, notably Name.variants etc.  This replaces
  4578 some popular functions from term.ML:
  4579 
  4580   Term.variant		->  Name.variant
  4581   Term.variantlist	->  Name.variant_list
  4582   Term.invent_names	->  Name.invent_list
  4583 
  4584 Note that low-level renaming rarely occurs in new code -- operations
  4585 from structure Variable are used instead (see below).
  4586 
  4587 * Pure: structure Variable provides fundamental operations for proper
  4588 treatment of fixed/schematic variables in a context.  For example,
  4589 Variable.import introduces fixes for schematics of given facts and
  4590 Variable.export reverses the effect (up to renaming) -- this replaces
  4591 various freeze_thaw operations.
  4592 
  4593 * Pure: structure Goal provides simple interfaces for
  4594 init/conclude/finish and tactical prove operations (replacing former
  4595 Tactic.prove).  Goal.prove is the canonical way to prove results
  4596 within a given context; Goal.prove_global is a degraded version for
  4597 theory level goals, including a global Drule.standard.  Note that
  4598 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  4599 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  4600 in a locale context).
  4601 
  4602 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  4603 and type checking (Syntax.check_term etc.), with common combinations
  4604 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  4605 which are considered legacy and await removal.
  4606 
  4607 * Pure/Syntax: generic interfaces for type unchecking
  4608 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  4609 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  4610 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  4611 available for convenience, but refer to the very same operations using
  4612 a mere theory instead of a full context.
  4613 
  4614 * Isar: simplified treatment of user-level errors, using exception
  4615 ERROR of string uniformly.  Function error now merely raises ERROR,
  4616 without any side effect on output channels.  The Isar toplevel takes
  4617 care of proper display of ERROR exceptions.  ML code may use plain
  4618 handle/can/try; cat_error may be used to concatenate errors like this:
  4619 
  4620   ... handle ERROR msg => cat_error msg "..."
  4621 
  4622 Toplevel ML code (run directly or through the Isar toplevel) may be
  4623 embedded into the Isar toplevel with exception display/debug like
  4624 this:
  4625 
  4626   Isar.toplevel (fn () => ...)
  4627 
  4628 INCOMPATIBILITY, removed special transform_error facilities, removed
  4629 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  4630 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  4631 -- use plain ERROR instead.
  4632 
  4633 * Isar: theory setup now has type (theory -> theory), instead of a
  4634 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  4635 
  4636 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  4637 ProofContext.debug/verbose flags.
  4638 
  4639 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  4640 theory before entering a proof state.  Transactions now always see a
  4641 quasi-functional intermediate checkpoint, both in interactive and
  4642 batch mode.
  4643 
  4644 * Isar: simplified interfaces for outer syntax.  Renamed
  4645 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  4646 OuterSyntax.add_parsers -- this functionality is now included in
  4647 OuterSyntax.command etc.  INCOMPATIBILITY.
  4648 
  4649 * Simplifier: the simpset of a running simplification process now
  4650 contains a proof context (cf. Simplifier.the_context), which is the
  4651 very context that the initial simpset has been retrieved from (by
  4652 simpset_of/local_simpset_of).  Consequently, all plug-in components
  4653 (solver, looper etc.) may depend on arbitrary proof data.
  4654 
  4655 * Simplifier.inherit_context inherits the proof context (plus the
  4656 local bounds) of the current simplification process; any simproc
  4657 etc. that calls the Simplifier recursively should do this!  Removed
  4658 former Simplifier.inherit_bounds, which is already included here --
  4659 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  4660 specify an explicit context using Simplifier.context/theory_context.
  4661 
  4662 * Simplifier/Classical Reasoner: more abstract interfaces
  4663 change_simpset/claset for modifying the simpset/claset reference of a
  4664 theory; raw versions simpset/claset_ref etc. have been discontinued --
  4665 INCOMPATIBILITY.
  4666 
  4667 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  4668 "Trueprop" etc.
  4669 
  4670 
  4671 *** System ***
  4672 
  4673 * settings: the default heap location within ISABELLE_HOME_USER now
  4674 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  4675 Isabelle installations.
  4676 
  4677 * isabelle-process: option -S (secure mode) disables some critical
  4678 operations, notably runtime compilation and evaluation of ML source
  4679 code.
  4680 
  4681 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  4682 
  4683 * Support for parallel execution, using native multicore support of
  4684 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  4685 independent theories, according to the given theory header
  4686 specifications. The maximum number of worker threads is specified via
  4687 usedir option -M or the "max-threads" setting in Proof General. A
  4688 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  4689 to 6 on a 8-core machine.  User-code needs to observe certain
  4690 guidelines for thread-safe programming, see appendix A in the Isar
  4691 Implementation manual.
  4692 
  4693 
  4694 
  4695 New in Isabelle2005 (October 2005)
  4696 ----------------------------------
  4697 
  4698 *** General ***
  4699 
  4700 * Theory headers: the new header syntax for Isar theories is
  4701 
  4702   theory <name>
  4703   imports <theory1> ... <theoryN>
  4704   uses <file1> ... <fileM>
  4705   begin
  4706 
  4707 where the 'uses' part is optional.  The previous syntax
  4708 
  4709   theory <name> = <theory1> + ... + <theoryN>:
  4710 
  4711 will disappear in the next release.  Use isatool fixheaders to convert
  4712 existing theory files.  Note that there is no change in ancient
  4713 non-Isar theories now, but these will disappear soon.
  4714 
  4715 * Theory loader: parent theories can now also be referred to via
  4716 relative and absolute paths.
  4717 
  4718 * Command 'find_theorems' searches for a list of criteria instead of a
  4719 list of constants. Known criteria are: intro, elim, dest, name:string,
  4720 simp:term, and any term. Criteria can be preceded by '-' to select
  4721 theorems that do not match. Intro, elim, dest select theorems that
  4722 match the current goal, name:s selects theorems whose fully qualified
  4723 name contain s, and simp:term selects all simplification rules whose
  4724 lhs match term.  Any other term is interpreted as pattern and selects
  4725 all theorems matching the pattern. Available in ProofGeneral under
  4726 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  4727 
  4728   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  4729 
  4730 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  4731 matching the current goal as introduction rule and not having "HOL."
  4732 in their name (i.e. not being defined in theory HOL).
  4733 
  4734 * Command 'thms_containing' has been discontinued in favour of
  4735 'find_theorems'; INCOMPATIBILITY.
  4736 
  4737 * Communication with Proof General is now 8bit clean, which means that
  4738 Unicode text in UTF-8 encoding may be used within theory texts (both
  4739 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4740 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4741 
  4742   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4743   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4744 
  4745 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4746 Classical Reasoner.  Typical big applications run around 2 times
  4747 faster.
  4748 
  4749 
  4750 *** Document preparation ***
  4751 
  4752 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4753 of raw sources.  Only those symbols that do not require additional
  4754 LaTeX packages (depending on comments in isabellesym.sty) are
  4755 displayed properly, everything else is left verbatim.  isatool display
  4756 and isatool print are used as front ends (these are subject to the
  4757 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4758 
  4759 * Command tags control specific markup of certain regions of text,
  4760 notably folding and hiding.  Predefined tags include "theory" (for
  4761 theory begin and end), "proof" for proof commands, and "ML" for
  4762 commands involving ML code; the additional tags "visible" and
  4763 "invisible" are unused by default.  Users may give explicit tag
  4764 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4765 interpretation of tags is determined by the LaTeX job during document
  4766 preparation: see option -V of isatool usedir, or options -n and -t of
  4767 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4768 \isadroptag.
  4769 
  4770 Several document versions may be produced at the same time via isatool
  4771 usedir (the generated index.html will link all of them).  Typical
  4772 specifications include ''-V document=theory,proof,ML'' to present
  4773 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4774 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4775 these parts without any formal replacement text.  The Isabelle site
  4776 default settings produce ''document'' and ''outline'' versions as
  4777 specified above.
  4778 
  4779 * Several new antiquotations:
  4780 
  4781   @{term_type term} prints a term with its type annotated;
  4782 
  4783   @{typeof term} prints the type of a term;
  4784 
  4785   @{const const} is the same as @{term const}, but checks that the
  4786   argument is a known logical constant;
  4787 
  4788   @{term_style style term} and @{thm_style style thm} print a term or
  4789   theorem applying a "style" to it
  4790 
  4791   @{ML text}
  4792 
  4793 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4794 definitions, equations, inequations etc., 'concl' printing only the
  4795 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4796 to print the specified premise.  TermStyle.add_style provides an ML
  4797 interface for introducing further styles.  See also the "LaTeX Sugar"
  4798 document practical applications.  The ML antiquotation prints
  4799 type-checked ML expressions verbatim.
  4800 
  4801 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4802 and 'text' support optional locale specification '(in loc)', which
  4803 specifies the default context for interpreting antiquotations.  For
  4804 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4805 
  4806 * Option 'locale=NAME' of antiquotations specifies an alternative
  4807 context interpreting the subsequent argument.  For example: @{thm
  4808 [locale=lattice] inf_assoc}.
  4809 
  4810 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4811 a proof context.
  4812 
  4813 * Proper output of antiquotations for theory commands involving a
  4814 proof context (such as 'locale' or 'theorem (in loc) ...').
  4815 
  4816 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4817 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4818 
  4819 * isatool usedir: new option -C (default true) controls whether option
  4820 -D should include a copy of the original document directory; -C false
  4821 prevents unwanted effects such as copying of administrative CVS data.
  4822 
  4823 
  4824 *** Pure ***
  4825 
  4826 * Considerably improved version of 'constdefs' command.  Now performs
  4827 automatic type-inference of declared constants; additional support for
  4828 local structure declarations (cf. locales and HOL records), see also
  4829 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4830 sequential dependencies of definitions within a single 'constdefs'
  4831 section; moreover, the declared name needs to be an identifier.  If
  4832 all fails, consider to fall back on 'consts' and 'defs' separately.
  4833 
  4834 * Improved indexed syntax and implicit structures.  First of all,
  4835 indexed syntax provides a notational device for subscripted
  4836 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4837 expressions.  Secondly, in a local context with structure
  4838 declarations, number indexes \<^sub>n or the empty index (default
  4839 number 1) refer to a certain fixed variable implicitly; option
  4840 show_structs controls printing of implicit structures.  Typical
  4841 applications of these concepts involve record types and locales.
  4842 
  4843 * New command 'no_syntax' removes grammar declarations (and
  4844 translations) resulting from the given syntax specification, which is
  4845 interpreted in the same manner as for the 'syntax' command.
  4846 
  4847 * 'Advanced' translation functions (parse_translation etc.) may depend
  4848 on the signature of the theory context being presently used for
  4849 parsing/printing, see also isar-ref manual.
  4850 
  4851 * Improved 'oracle' command provides a type-safe interface to turn an
  4852 ML expression of type theory -> T -> term into a primitive rule of
  4853 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4854 is already included here); see also FOL/ex/IffExample.thy;
  4855 INCOMPATIBILITY.
  4856 
  4857 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4858 before); "cI" is no longer bound, use "c.intro" instead.
  4859 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4860 axclasses vs. locales.
  4861 
  4862 * Improved internal renaming of symbolic identifiers -- attach primes
  4863 instead of base 26 numbers.
  4864 
  4865 * New flag show_question_marks controls printing of leading question
  4866 marks in schematic variable names.
  4867 
  4868 * In schematic variable names, *any* symbol following \<^isub> or
  4869 \<^isup> is now treated as part of the base name.  For example, the
  4870 following works without printing of awkward ".0" indexes:
  4871 
  4872   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4873     by simp
  4874 
  4875 * Inner syntax includes (*(*nested*) comments*).
  4876 
  4877 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4878 annotations as "(00...)".
  4879 
  4880 * Clear separation of logical types and nonterminals, where the latter
  4881 may only occur in 'syntax' specifications or type abbreviations.
  4882 Before that distinction was only partially implemented via type class
  4883 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4884 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4885 exotic syntax specifications may require further adaption
  4886 (e.g. Cube/Cube.thy).
  4887 
  4888 * Removed obsolete type class "logic", use the top sort {} instead.
  4889 Note that non-logical types should be declared as 'nonterminals'
  4890 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4891 specifications.
  4892 
  4893 * Attributes 'induct' and 'cases': type or set names may now be
  4894 locally fixed variables as well.
  4895 
  4896 * Simplifier: can now control the depth to which conditional rewriting
  4897 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4898 Limit.
  4899 
  4900 * Simplifier: simplification procedures may now take the current
  4901 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4902 interface), which is very useful for calling the Simplifier
  4903 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4904 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4905 low-level mk_simproc no longer applies Logic.varify internally, to
  4906 allow for use in a context of fixed variables.
  4907 
  4908 * thin_tac now works even if the assumption being deleted contains !!
  4909 or ==>.  More generally, erule now works even if the major premise of
  4910 the elimination rule contains !! or ==>.
  4911 
  4912 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4913 
  4914 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4915 from Pure, which contains all common declarations already.  Both
  4916 theories are defined via plain Isabelle/Isar .thy files.
  4917 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4918 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4919 use isatool fixcpure to adapt your theory and ML sources.
  4920 
  4921 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4922 selections of theorems in named facts via index ranges.
  4923 
  4924 * 'print_theorems': in theory mode, really print the difference
  4925 wrt. the last state (works for interactive theory development only),
  4926 in proof mode print all local facts (cf. 'print_facts');
  4927 
  4928 * 'hide': option '(open)' hides only base names.
  4929 
  4930 * More efficient treatment of intermediate checkpoints in interactive
  4931 theory development.
  4932 
  4933 * Code generator is now invoked via code_module (incremental code
  4934 generation) and code_library (modular code generation, ML structures
  4935 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4936 must be quoted when used as identifiers.
  4937 
  4938 * New 'value' command for reading, evaluating and printing terms using
  4939 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4940 quoted when used as identifier.
  4941 
  4942 
  4943 *** Locales ***
  4944 
  4945 * New commands for the interpretation of locale expressions in
  4946 theories (1), locales (2) and proof contexts (3).  These generate
  4947 proof obligations from the expression specification.  After the
  4948 obligations have been discharged, theorems of the expression are added
  4949 to the theory, target locale or proof context.  The synopsis of the
  4950 commands is a follows:
  4951 
  4952   (1) interpretation expr inst
  4953   (2) interpretation target < expr
  4954   (3) interpret expr inst
  4955 
  4956 Interpretation in theories and proof contexts require a parameter
  4957 instantiation of terms from the current context.  This is applied to
  4958 specifications and theorems of the interpreted expression.
  4959 Interpretation in locales only permits parameter renaming through the
  4960 locale expression.  Interpretation is smart in that interpretations
  4961 that are active already do not occur in proof obligations, neither are
  4962 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4963 inspect active interpretations of a particular locale.  For details,
  4964 see the Isar Reference manual.  Examples can be found in
  4965 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4966 
  4967 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4968 'interpret' instead.
  4969 
  4970 * New context element 'constrains' for adding type constraints to
  4971 parameters.
  4972 
  4973 * Context expressions: renaming of parameters with syntax
  4974 redeclaration.
  4975 
  4976 * Locale declaration: 'includes' disallowed.
  4977 
  4978 * Proper static binding of attribute syntax -- i.e. types / terms /
  4979 facts mentioned as arguments are always those of the locale definition
  4980 context, independently of the context of later invocations.  Moreover,
  4981 locale operations (renaming and type / term instantiation) are applied
  4982 to attribute arguments as expected.
  4983 
  4984 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4985 actual attributes; rare situations may require Attrib.attribute to
  4986 embed those attributes into Attrib.src that lack concrete syntax.
  4987 Attribute implementations need to cooperate properly with the static
  4988 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4989 Attrib.XXX_thm etc. already do the right thing without further
  4990 intervention.  Only unusual applications -- such as "where" or "of"
  4991 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4992 on the context and the facts involved -- may have to assign parsed
  4993 values to argument tokens explicitly.
  4994 
  4995 * Changed parameter management in theorem generation for long goal
  4996 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4997 theorem statement in rare situations.
  4998 
  4999 * Locale inspection command 'print_locale' omits notes elements.  Use
  5000 'print_locale!' to have them included in the output.
  5001 
  5002 
  5003 *** Provers ***
  5004 
  5005 * Provers/hypsubst.ML: improved version of the subst method, for
  5006 single-step rewriting: it now works in bound variable contexts. New is
  5007 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  5008 rewrite a different subterm than the original subst method, which is
  5009 still available as 'simplesubst'.
  5010 
  5011 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  5012 and quasi orders.
  5013 
  5014 * Provers/trancl.ML: new transitivity reasoner for transitive and
  5015 reflexive-transitive closure of relations.
  5016 
  5017 * Provers/blast.ML: new reference depth_limit to make blast's depth
  5018 limit (previously hard-coded with a value of 20) user-definable.
  5019 
  5020 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  5021 is peformed already.  Object-logics merely need to finish their
  5022 initial simpset configuration as before.  INCOMPATIBILITY.
  5023 
  5024 
  5025 *** HOL ***
  5026 
  5027 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  5028 
  5029   syntax (epsilon)
  5030     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  5031 
  5032 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  5033 and x-symbol; use option '-m epsilon' to get it actually printed.
  5034 Moreover, the mathematically important symbolic identifier \<epsilon>
  5035 becomes available as variable, constant etc.  INCOMPATIBILITY,
  5036 
  5037 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  5038 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  5039 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  5040 support corresponding Isar calculations.
  5041 
  5042 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  5043 instead of ":".
  5044 
  5045 * theory SetInterval: changed the syntax for open intervals:
  5046 
  5047   Old       New
  5048   {..n(}    {..<n}
  5049   {)n..}    {n<..}
  5050   {m..n(}   {m..<n}
  5051   {)m..n}   {m<..n}
  5052   {)m..n(}  {m<..<n}
  5053 
  5054 The old syntax is still supported but will disappear in the next
  5055 release.  For conversion use the following Emacs search and replace
  5056 patterns (these are not perfect but work quite well):
  5057 
  5058   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  5059   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  5060 
  5061 * Theory Commutative_Ring (in Library): method comm_ring for proving
  5062 equalities in commutative rings; method 'algebra' provides a generic
  5063 interface.
  5064 
  5065 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  5066 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  5067 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  5068 be a tuple pattern.
  5069 
  5070 Some new syntax forms are available:
  5071 
  5072   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  5073   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  5074   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  5075   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  5076 
  5077 The latter form "\<Sum>x < k. e" used to be based on a separate
  5078 function "Summation", which has been discontinued.
  5079 
  5080 * theory Finite_Set: in structured induction proofs, the insert case
  5081 is now 'case (insert x F)' instead of the old counterintuitive 'case
  5082 (insert F x)'.
  5083 
  5084 * The 'refute' command has been extended to support a much larger
  5085 fragment of HOL, including axiomatic type classes, constdefs and
  5086 typedefs, inductive datatypes and recursion.
  5087 
  5088 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  5089 Requires zChaff with proof generation to be installed.  See
  5090 HOL/ex/SAT_Examples.thy for examples.
  5091 
  5092 * Datatype induction via method 'induct' now preserves the name of the
  5093 induction variable. For example, when proving P(xs::'a list) by
  5094 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  5095 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  5096 in unstructured proof scripts.
  5097 
  5098 * Reworked implementation of records.  Improved scalability for
  5099 records with many fields, avoiding performance problems for type
  5100 inference. Records are no longer composed of nested field types, but
  5101 of nested extension types. Therefore the record type only grows linear
  5102 in the number of extensions and not in the number of fields.  The
  5103 top-level (users) view on records is preserved.  Potential
  5104 INCOMPATIBILITY only in strange cases, where the theory depends on the
  5105 old record representation. The type generated for a record is called
  5106 <record_name>_ext_type.
  5107 
  5108 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  5109 proofs triggered by a record definition or a simproc (if
  5110 quick_and_dirty is enabled).  Definitions of large records can take
  5111 quite long.
  5112 
  5113 New simproc record_upd_simproc for simplification of multiple record
  5114 updates enabled by default.  Moreover, trivial updates are also
  5115 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  5116 occasionally, since simplification is more powerful by default.
  5117 
  5118 * typedef: proper support for polymorphic sets, which contain extra
  5119 type-variables in the term.
  5120 
  5121 * Simplifier: automatically reasons about transitivity chains
  5122 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  5123 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  5124 old proofs break occasionally as simplification may now solve more
  5125 goals than previously.
  5126 
  5127 * Simplifier: converts x <= y into x = y if assumption y <= x is
  5128 present.  Works for all partial orders (class "order"), in particular
  5129 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  5130 just like y <= x.
  5131 
  5132 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  5133 bound variable or a constant then the let is unfolded.  Otherwise
  5134 first a is simplified to b, and then f b is simplified to g. If
  5135 possible we abstract b from g arriving at "let x = b in h x",
  5136 otherwise we unfold the let and arrive at g.  The simproc can be
  5137 enabled/disabled by the reference use_let_simproc.  Potential
  5138 INCOMPATIBILITY since simplification is more powerful by default.
  5139 
  5140 * Classical reasoning: the meson method now accepts theorems as arguments.
  5141 
  5142 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  5143 jobs to provide advice on the provability of subgoals.
  5144 
  5145 * Theory OrderedGroup and Ring_and_Field: various additions and
  5146 improvements to faciliate calculations involving equalities and
  5147 inequalities.
  5148 
  5149 The following theorems have been eliminated or modified
  5150 (INCOMPATIBILITY):
  5151 
  5152   abs_eq             now named abs_of_nonneg
  5153   abs_of_ge_0        now named abs_of_nonneg
  5154   abs_minus_eq       now named abs_of_nonpos
  5155   imp_abs_id         now named abs_of_nonneg
  5156   imp_abs_neg_id     now named abs_of_nonpos
  5157   mult_pos           now named mult_pos_pos
  5158   mult_pos_le        now named mult_nonneg_nonneg
  5159   mult_pos_neg_le    now named mult_nonneg_nonpos
  5160   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  5161   mult_neg           now named mult_neg_neg
  5162   mult_neg_le        now named mult_nonpos_nonpos
  5163 
  5164 * The following lemmas in Ring_and_Field have been added to the simplifier:
  5165      
  5166      zero_le_square
  5167      not_square_less_zero 
  5168 
  5169   The following lemmas have been deleted from Real/RealPow:
  5170   
  5171      realpow_zero_zero
  5172      realpow_two
  5173      realpow_less
  5174      zero_le_power
  5175      realpow_two_le
  5176      abs_realpow_two
  5177      realpow_two_abs     
  5178 
  5179 * Theory Parity: added rules for simplifying exponents.
  5180 
  5181 * Theory List:
  5182 
  5183 The following theorems have been eliminated or modified
  5184 (INCOMPATIBILITY):
  5185 
  5186   list_all_Nil       now named list_all.simps(1)
  5187   list_all_Cons      now named list_all.simps(2)
  5188   list_all_conv      now named list_all_iff
  5189   set_mem_eq         now named mem_iff
  5190 
  5191 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  5192 asymptotic "big O" calculations.  See the notes in BigO.thy.
  5193 
  5194 
  5195 *** HOL-Complex ***
  5196 
  5197 * Theory RealDef: better support for embedding natural numbers and
  5198 integers in the reals.
  5199 
  5200 The following theorems have been eliminated or modified
  5201 (INCOMPATIBILITY):
  5202 
  5203   exp_ge_add_one_self  now requires no hypotheses
  5204   real_of_int_add      reversed direction of equality (use [symmetric])
  5205   real_of_int_minus    reversed direction of equality (use [symmetric])
  5206   real_of_int_diff     reversed direction of equality (use [symmetric])
  5207   real_of_int_mult     reversed direction of equality (use [symmetric])
  5208 
  5209 * Theory RComplete: expanded support for floor and ceiling functions.
  5210 
  5211 * Theory Ln is new, with properties of the natural logarithm
  5212 
  5213 * Hyperreal: There is a new type constructor "star" for making
  5214 nonstandard types.  The old type names are now type synonyms:
  5215 
  5216   hypreal = real star
  5217   hypnat = nat star
  5218   hcomplex = complex star
  5219 
  5220 * Hyperreal: Many groups of similarly-defined constants have been
  5221 replaced by polymorphic versions (INCOMPATIBILITY):
  5222 
  5223   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  5224 
  5225   starset      <-- starsetNat, starsetC
  5226   *s*          <-- *sNat*, *sc*
  5227   starset_n    <-- starsetNat_n, starsetC_n
  5228   *sn*         <-- *sNatn*, *scn*
  5229   InternalSets <-- InternalNatSets, InternalCSets
  5230 
  5231   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  5232   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  5233   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  5234   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  5235   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  5236 
  5237 * Hyperreal: Many type-specific theorems have been removed in favor of
  5238 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  5239 
  5240   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  5241   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  5242   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  5243   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  5244   right_minus <-- hypreal_add_minus
  5245   left_minus <-- {hypreal,hcomplex}_add_minus_left
  5246   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  5247   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  5248   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  5249   mult_1_right <-- hcomplex_mult_one_right
  5250   mult_zero_left <-- hcomplex_mult_zero_left
  5251   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  5252   right_distrib <-- hypnat_add_mult_distrib2
  5253   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  5254   right_inverse <-- hypreal_mult_inverse
  5255   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  5256   order_refl <-- {hypreal,hypnat}_le_refl
  5257   order_trans <-- {hypreal,hypnat}_le_trans
  5258   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  5259   order_less_le <-- {hypreal,hypnat}_less_le
  5260   linorder_linear <-- {hypreal,hypnat}_le_linear
  5261   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  5262   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  5263   add_nonneg_nonneg <-- hypreal_le_add_order
  5264 
  5265 * Hyperreal: Separate theorems having to do with type-specific
  5266 versions of constants have been merged into theorems that apply to the
  5267 new polymorphic constants (INCOMPATIBILITY):
  5268 
  5269   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  5270   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  5271   STAR_Un <-- {STAR,NatStar,STARC}_Un
  5272   STAR_Int <-- {STAR,NatStar,STARC}_Int
  5273   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  5274   STAR_subset <-- {STAR,NatStar,STARC}_subset
  5275   STAR_mem <-- {STAR,NatStar,STARC}_mem
  5276   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  5277   STAR_diff <-- {STAR,STARC}_diff
  5278   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  5279     STARC_hcomplex_of_complex}_image_subset
  5280   starset_n_Un <-- starset{Nat,C}_n_Un
  5281   starset_n_Int <-- starset{Nat,C}_n_Int
  5282   starset_n_Compl <-- starset{Nat,C}_n_Compl
  5283   starset_n_diff <-- starset{Nat,C}_n_diff
  5284   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  5285   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  5286   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  5287   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  5288   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  5289   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  5290   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  5291   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  5292   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  5293   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  5294   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  5295   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  5296   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  5297   starfun_diff <-- starfun{C,RC,CR}_diff
  5298   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  5299   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  5300   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  5301   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  5302   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  5303   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  5304   starfun_Id <-- starfunC_Id
  5305   starfun_approx <-- starfun{Nat,CR}_approx
  5306   starfun_capprox <-- starfun{C,RC}_capprox
  5307   starfun_abs <-- starfunNat_rabs
  5308   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  5309   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  5310   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  5311   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  5312   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  5313   starfun_add_approx <-- starfunCR_add_approx
  5314   starfun_inverse_inverse <-- starfunC_inverse_inverse
  5315   starfun_divide <-- starfun{C,CR,RC}_divide
  5316   starfun_n <-- starfun{Nat,C}_n
  5317   starfun_n_mult <-- starfun{Nat,C}_n_mult
  5318   starfun_n_add <-- starfun{Nat,C}_n_add
  5319   starfun_n_add_minus <-- starfunNat_n_add_minus
  5320   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  5321   starfun_n_minus <-- starfun{Nat,C}_n_minus
  5322   starfun_n_eq <-- starfun{Nat,C}_n_eq
  5323 
  5324   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  5325   star_n_minus <-- {hypreal,hcomplex}_minus
  5326   star_n_diff <-- {hypreal,hcomplex}_diff
  5327   star_n_mult <-- {hypreal,hcomplex}_mult
  5328   star_n_inverse <-- {hypreal,hcomplex}_inverse
  5329   star_n_le <-- {hypreal,hypnat}_le
  5330   star_n_less <-- {hypreal,hypnat}_less
  5331   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  5332   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  5333   star_n_abs <-- hypreal_hrabs
  5334   star_n_divide <-- hcomplex_divide
  5335 
  5336   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  5337   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  5338   star_of_diff <-- hypreal_of_real_diff
  5339   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  5340   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  5341   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  5342   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  5343   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  5344   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  5345   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  5346   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  5347   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  5348   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  5349   star_of_number_of <-- {hypreal,hcomplex}_number_of
  5350   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  5351   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  5352   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  5353   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  5354   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  5355   star_of_power <-- hypreal_of_real_power
  5356   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  5357 
  5358 * Hyperreal: new method "transfer" that implements the transfer
  5359 principle of nonstandard analysis. With a subgoal that mentions
  5360 nonstandard types like "'a star", the command "apply transfer"
  5361 replaces it with an equivalent one that mentions only standard types.
  5362 To be successful, all free variables must have standard types; non-
  5363 standard variables must have explicit universal quantifiers.
  5364 
  5365 * Hyperreal: A theory of Taylor series.
  5366 
  5367 
  5368 *** HOLCF ***
  5369 
  5370 * Discontinued special version of 'constdefs' (which used to support
  5371 continuous functions) in favor of the general Pure one with full
  5372 type-inference.
  5373 
  5374 * New simplification procedure for solving continuity conditions; it
  5375 is much faster on terms with many nested lambda abstractions (cubic
  5376 instead of exponential time).
  5377 
  5378 * New syntax for domain package: selector names are now optional.
  5379 Parentheses should be omitted unless argument is lazy, for example:
  5380 
  5381   domain 'a stream = cons "'a" (lazy "'a stream")
  5382 
  5383 * New command 'fixrec' for defining recursive functions with pattern
  5384 matching; defining multiple functions with mutual recursion is also
  5385 supported.  Patterns may include the constants cpair, spair, up, sinl,
  5386 sinr, or any data constructor defined by the domain package. The given
  5387 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  5388 syntax and examples.
  5389 
  5390 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  5391 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  5392 but the proof obligation additionally includes an admissibility
  5393 requirement. The packages generate instances of class cpo or pcpo,
  5394 with continuity and strictness theorems for Rep and Abs.
  5395 
  5396 * HOLCF: Many theorems have been renamed according to a more standard naming
  5397 scheme (INCOMPATIBILITY):
  5398 
  5399   foo_inject:  "foo$x = foo$y ==> x = y"
  5400   foo_eq:      "(foo$x = foo$y) = (x = y)"
  5401   foo_less:    "(foo$x << foo$y) = (x << y)"
  5402   foo_strict:  "foo$UU = UU"
  5403   foo_defined: "... ==> foo$x ~= UU"
  5404   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  5405 
  5406 
  5407 *** ZF ***
  5408 
  5409 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  5410 including the First Isomorphism Theorem (on quotienting by the kernel
  5411 of a homomorphism).
  5412 
  5413 * ZF/Simplifier: install second copy of type solver that actually
  5414 makes use of TC rules declared to Isar proof contexts (or locales);
  5415 the old version is still required for ML proof scripts.
  5416 
  5417 
  5418 *** Cube ***
  5419 
  5420 * Converted to Isar theory format; use locales instead of axiomatic
  5421 theories.
  5422 
  5423 
  5424 *** ML ***
  5425 
  5426 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  5427 for ||>, ||>>, |>>,
  5428 
  5429 * Pure/library.ML no longer defines its own option datatype, but uses
  5430 that of the SML basis, which has constructors NONE and SOME instead of
  5431 None and Some, as well as exception Option.Option instead of OPTION.
  5432 The functions the, if_none, is_some, is_none have been adapted
  5433 accordingly, while Option.map replaces apsome.
  5434 
  5435 * Pure/library.ML: the exception LIST has been given up in favour of
  5436 the standard exceptions Empty and Subscript, as well as
  5437 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  5438 superceded by the standard hd and tl functions etc.
  5439 
  5440 A number of basic list functions are no longer exported to the ML
  5441 toplevel, as they are variants of predefined functions.  The following
  5442 suggests how one can translate existing code:
  5443 
  5444     rev_append xs ys = List.revAppend (xs, ys)
  5445     nth_elem (i, xs) = List.nth (xs, i)
  5446     last_elem xs = List.last xs
  5447     flat xss = List.concat xss
  5448     seq fs = List.app fs
  5449     partition P xs = List.partition P xs
  5450     mapfilter f xs = List.mapPartial f xs
  5451 
  5452 * Pure/library.ML: several combinators for linear functional
  5453 transformations, notably reverse application and composition:
  5454 
  5455   x |> f                f #> g
  5456   (x, y) |-> f          f #-> g
  5457 
  5458 * Pure/library.ML: introduced/changed precedence of infix operators:
  5459 
  5460   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  5461   infix 2 ?;
  5462   infix 3 o oo ooo oooo;
  5463   infix 4 ~~ upto downto;
  5464 
  5465 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  5466 infix operators.
  5467 
  5468 * Pure/library.ML: natural list combinators fold, fold_rev, and
  5469 fold_map support linear functional transformations and nesting.  For
  5470 example:
  5471 
  5472   fold f [x1, ..., xN] y =
  5473     y |> f x1 |> ... |> f xN
  5474 
  5475   (fold o fold) f [xs1, ..., xsN] y =
  5476     y |> fold f xs1 |> ... |> fold f xsN
  5477 
  5478   fold f [x1, ..., xN] =
  5479     f x1 #> ... #> f xN
  5480 
  5481   (fold o fold) f [xs1, ..., xsN] =
  5482     fold f xs1 #> ... #> fold f xsN
  5483 
  5484 * Pure/library.ML: the following selectors on type 'a option are
  5485 available:
  5486 
  5487   the:               'a option -> 'a  (*partial*)
  5488   these:             'a option -> 'a  where 'a = 'b list
  5489   the_default: 'a -> 'a option -> 'a
  5490   the_list:          'a option -> 'a list
  5491 
  5492 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5493 basic operations for association lists, following natural argument
  5494 order; moreover the explicit equality predicate passed here avoids
  5495 potentially expensive polymorphic runtime equality checks.
  5496 The old functions may be expressed as follows:
  5497 
  5498   assoc = uncurry (AList.lookup (op =))
  5499   assocs = these oo AList.lookup (op =)
  5500   overwrite = uncurry (AList.update (op =)) o swap
  5501 
  5502 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5503 
  5504   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  5505   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  5506 
  5507 replacing make_keylist and keyfilter (occassionally used)
  5508 Naive rewrites:
  5509 
  5510   make_keylist = AList.make
  5511   keyfilter = AList.find (op =)
  5512 
  5513 * eq_fst and eq_snd now take explicit equality parameter, thus
  5514   avoiding eqtypes. Naive rewrites:
  5515 
  5516     eq_fst = eq_fst (op =)
  5517     eq_snd = eq_snd (op =)
  5518 
  5519 * Removed deprecated apl and apr (rarely used).
  5520   Naive rewrites:
  5521 
  5522     apl (n, op) =>>= curry op n
  5523     apr (op, m) =>>= fn n => op (n, m)
  5524 
  5525 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  5526 provides a reasonably efficient light-weight implementation of sets as
  5527 lists.
  5528 
  5529 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  5530 few new operations; existing lookup and update are now curried to
  5531 follow natural argument order (for use with fold etc.);
  5532 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  5533 
  5534 * Pure/General: output via the Isabelle channels of
  5535 writeln/warning/error etc. is now passed through Output.output, with a
  5536 hook for arbitrary transformations depending on the print_mode
  5537 (cf. Output.add_mode -- the first active mode that provides a output
  5538 function wins).  Already formatted output may be embedded into further
  5539 text via Output.raw; the result of Pretty.string_of/str_of and derived
  5540 functions (string_of_term/cterm/thm etc.) is already marked raw to
  5541 accommodate easy composition of diagnostic messages etc.  Programmers
  5542 rarely need to care about Output.output or Output.raw at all, with
  5543 some notable exceptions: Output.output is required when bypassing the
  5544 standard channels (writeln etc.), or in token translations to produce
  5545 properly formatted results; Output.raw is required when capturing
  5546 already output material that will eventually be presented to the user
  5547 a second time.  For the default print mode, both Output.output and
  5548 Output.raw have no effect.
  5549 
  5550 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  5551 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  5552 cumulative results are displayed at the end of a batch session.
  5553 
  5554 * Pure/General: File.sysify_path and File.quote_sysify path have been
  5555 replaced by File.platform_path and File.shell_path (with appropriate
  5556 hooks).  This provides a clean interface for unusual systems where the
  5557 internal and external process view of file names are different.
  5558 
  5559 * Pure: more efficient orders for basic syntactic entities: added
  5560 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  5561 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  5562 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  5563 orders now -- potential INCOMPATIBILITY for code that depends on a
  5564 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  5565 Library.sort_strings on result).
  5566 
  5567 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  5568 fold_types traverse types/terms from left to right, observing natural
  5569 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  5570 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  5571 
  5572 * Pure: name spaces have been refined, with significant changes of the
  5573 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  5574 to extern(_table).  The plain name entry path is superceded by a
  5575 general 'naming' context, which also includes the 'policy' to produce
  5576 a fully qualified name and external accesses of a fully qualified
  5577 name; NameSpace.extend is superceded by context dependent
  5578 Sign.declare_name.  Several theory and proof context operations modify
  5579 the naming context.  Especially note Theory.restore_naming and
  5580 ProofContext.restore_naming to get back to a sane state; note that
  5581 Theory.add_path is no longer sufficient to recover from
  5582 Theory.absolute_path in particular.
  5583 
  5584 * Pure: new flags short_names (default false) and unique_names
  5585 (default true) for controlling output of qualified names.  If
  5586 short_names is set, names are printed unqualified.  If unique_names is
  5587 reset, the name prefix is reduced to the minimum required to achieve
  5588 the original result when interning again, even if there is an overlap
  5589 with earlier declarations.
  5590 
  5591 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  5592 now 'extend', and 'merge' gets an additional Pretty.pp argument
  5593 (useful for printing error messages).  INCOMPATIBILITY.
  5594 
  5595 * Pure: major reorganization of the theory context.  Type Sign.sg and
  5596 Theory.theory are now identified, referring to the universal
  5597 Context.theory (see Pure/context.ML).  Actual signature and theory
  5598 content is managed as theory data.  The old code and interfaces were
  5599 spread over many files and structures; the new arrangement introduces
  5600 considerable INCOMPATIBILITY to gain more clarity:
  5601 
  5602   Context -- theory management operations (name, identity, inclusion,
  5603     parents, ancestors, merge, etc.), plus generic theory data;
  5604 
  5605   Sign -- logical signature and syntax operations (declaring consts,
  5606     types, etc.), plus certify/read for common entities;
  5607 
  5608   Theory -- logical theory operations (stating axioms, definitions,
  5609     oracles), plus a copy of logical signature operations (consts,
  5610     types, etc.); also a few basic management operations (Theory.copy,
  5611     Theory.merge, etc.)
  5612 
  5613 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  5614 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  5615 for convenience -- they merely return the theory.
  5616 
  5617 * Pure: type Type.tsig is superceded by theory in most interfaces.
  5618 
  5619 * Pure: the Isar proof context type is already defined early in Pure
  5620 as Context.proof (note that ProofContext.context and Proof.context are
  5621 aliases, where the latter is the preferred name).  This enables other
  5622 Isabelle components to refer to that type even before Isar is present.
  5623 
  5624 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  5625 typeK, constK, axiomK, oracleK), but provide explicit operations for
  5626 any of these kinds.  For example, Sign.intern typeK is now
  5627 Sign.intern_type, Theory.hide_space Sign.typeK is now
  5628 Theory.hide_types.  Also note that former
  5629 Theory.hide_classes/types/consts are now
  5630 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  5631 internalize their arguments!  INCOMPATIBILITY.
  5632 
  5633 * Pure: get_thm interface (of PureThy and ProofContext) expects
  5634 datatype thmref (with constructors Name and NameSelection) instead of
  5635 plain string -- INCOMPATIBILITY;
  5636 
  5637 * Pure: cases produced by proof methods specify options, where NONE
  5638 means to remove case bindings -- INCOMPATIBILITY in
  5639 (RAW_)METHOD_CASES.
  5640 
  5641 * Pure: the following operations retrieve axioms or theorems from a
  5642 theory node or theory hierarchy, respectively:
  5643 
  5644   Theory.axioms_of: theory -> (string * term) list
  5645   Theory.all_axioms_of: theory -> (string * term) list
  5646   PureThy.thms_of: theory -> (string * thm) list
  5647   PureThy.all_thms_of: theory -> (string * thm) list
  5648 
  5649 * Pure: print_tac now outputs the goal through the trace channel.
  5650 
  5651 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  5652 Reference Toplevel.debug (default false) controls detailed printing
  5653 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  5654 controls execution profiling -- set to 1 for time and 2 for space
  5655 (both increase the runtime).
  5656 
  5657 * Isar session: The initial use of ROOT.ML is now always timed,
  5658 i.e. the log will show the actual process times, in contrast to the
  5659 elapsed wall-clock time that the outer shell wrapper produces.
  5660 
  5661 * Simplifier: improved handling of bound variables (nameless
  5662 representation, avoid allocating new strings).  Simprocs that invoke
  5663 the Simplifier recursively should use Simplifier.inherit_bounds to
  5664 avoid local name clashes.  Failure to do so produces warnings
  5665 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  5666 for further details.
  5667 
  5668 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  5669 bindings for all theorems stored within a given theory; this may help
  5670 in porting non-Isar theories to Isar ones, while keeping ML proof
  5671 scripts for the time being.
  5672 
  5673 * ML operator HTML.with_charset specifies the charset begin used for
  5674 generated HTML files.  For example:
  5675 
  5676   HTML.with_charset "utf-8" use_thy "Hebrew";
  5677   HTML.with_charset "utf-8" use_thy "Chinese";
  5678 
  5679 
  5680 *** System ***
  5681 
  5682 * Allow symlinks to all proper Isabelle executables (Isabelle,
  5683 isabelle, isatool etc.).
  5684 
  5685 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  5686 isatool doc, isatool mkdir, display_drafts etc.).
  5687 
  5688 * isatool usedir: option -f allows specification of the ML file to be
  5689 used by Isabelle; default is ROOT.ML.
  5690 
  5691 * New isatool version outputs the version identifier of the Isabelle
  5692 distribution being used.
  5693 
  5694 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  5695 (containing Boolean satisfiability problems) into Isabelle/HOL
  5696 theories.
  5697 
  5698 
  5699 
  5700 New in Isabelle2004 (April 2004)
  5701 --------------------------------
  5702 
  5703 *** General ***
  5704 
  5705 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  5706   Replaces linorder.ML.
  5707 
  5708 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  5709   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  5710   (\<a>...\<z>), are now considered normal letters, and can therefore
  5711   be used anywhere where an ASCII letter (a...zA...Z) has until
  5712   now. COMPATIBILITY: This obviously changes the parsing of some
  5713   terms, especially where a symbol has been used as a binder, say
  5714   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  5715   as an identifier.  Fix it by inserting a space around former
  5716   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  5717   existing theory and ML files.
  5718 
  5719 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  5720 
  5721 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  5722   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  5723   a normal (but invisible) letter. For multiple letter subscripts repeat
  5724   \<^isub> like this: x\<^isub>1\<^isub>2.
  5725 
  5726 * Pure: There are now sub-/superscripts that can span more than one
  5727   character. Text between \<^bsub> and \<^esub> is set in subscript in
  5728   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  5729   superscript. The new control characters are not identifier parts.
  5730 
  5731 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5732   content of "..." to the latex file instead of \isacntrl... . The "..."
  5733   may consist of any printable characters excluding the end bracket >.
  5734 
  5735 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5736   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5737   declare constants "final", which prevents their being given a definition
  5738   later.  It is useful for constants whose behaviour is fixed axiomatically
  5739   rather than definitionally, such as the meta-logic connectives.
  5740 
  5741 * Pure: 'instance' now handles general arities with general sorts
  5742   (i.e. intersections of classes),
  5743 
  5744 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5745   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5746   It can be changed to alter the colors/layout of generated pages.
  5747 
  5748 
  5749 *** Isar ***
  5750 
  5751 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5752   cut_tac, subgoal_tac and thin_tac:
  5753   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5754     locales are no longer forced to write Isar proof scripts.
  5755     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5756     emulations.
  5757   - INCOMPATIBILITY: names of variables to be instantiated may no
  5758     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5759     This is consistent with the instantiation attribute "where".
  5760 
  5761 * Attributes "where" and "of":
  5762   - Now take type variables of instantiated theorem into account when reading
  5763     the instantiation string.  This fixes a bug that caused instantiated
  5764     theorems to have too special types in some circumstances.
  5765   - "where" permits explicit instantiations of type variables.
  5766 
  5767 * Calculation commands "moreover" and "also" no longer interfere with
  5768   current facts ("this"), admitting arbitrary combinations with "then"
  5769   and derived forms.
  5770 
  5771 * Locales:
  5772   - Goal statements involving the context element "includes" no longer
  5773     generate theorems with internal delta predicates (those ending on
  5774     "_axioms") in the premise.
  5775     Resolve particular premise with <locale>.intro to obtain old form.
  5776   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5777     specification and "includes" elements in goal statement.
  5778   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5779     [intro?] and [elim?] (respectively) by default.
  5780   - Experimental command for instantiation of locales in proof contexts:
  5781         instantiate <label>[<attrs>]: <loc>
  5782     Instantiates locale <loc> and adds all its theorems to the current context
  5783     taking into account their attributes.  Label and attrs are optional
  5784     modifiers, like in theorem declarations.  If present, names of
  5785     instantiated theorems are qualified with <label>, and the attributes
  5786     <attrs> are applied after any attributes these theorems might have already.
  5787       If the locale has assumptions, a chained fact of the form
  5788     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5789     are derived.  The command does not support old-style locales declared
  5790     with "locale (open)".
  5791       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5792 
  5793 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5794   (Isar) contexts.
  5795 
  5796 
  5797 *** HOL ***
  5798 
  5799 * Proof import: new image HOL4 contains the imported library from
  5800   the HOL4 system with about 2500 theorems. It is imported by
  5801   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5802   can be used like any other Isabelle image.  See
  5803   HOL/Import/HOL/README for more information.
  5804 
  5805 * Simplifier:
  5806   - Much improved handling of linear and partial orders.
  5807     Reasoners for linear and partial orders are set up for type classes
  5808     "linorder" and "order" respectively, and are added to the default simpset
  5809     as solvers.  This means that the simplifier can build transitivity chains
  5810     to solve goals from the assumptions.
  5811   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5812     of blast or auto after simplification become unnecessary because the goal
  5813     is solved by simplification already.
  5814 
  5815 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5816     all proved in axiomatic type classes for semirings, rings and fields.
  5817 
  5818 * Numerics:
  5819   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5820     now formalized using the Ring_and_Field theory mentioned above.
  5821   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5822     than before, because now they are set up once in a generic manner.
  5823   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5824     Look for the general versions in Ring_and_Field (and Power if they concern
  5825     exponentiation).
  5826 
  5827 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5828 
  5829 * Records:
  5830   - Record types are now by default printed with their type abbreviation
  5831     instead of the list of all field types. This can be configured via
  5832     the reference "print_record_type_abbr".
  5833   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5834     (not enabled by default).
  5835   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5836     EX x. x = sel r to True (not enabled by default).
  5837   - Tactic "record_split_simp_tac" to split and simplify records added.
  5838 
  5839 * 'specification' command added, allowing for definition by
  5840   specification.  There is also an 'ax_specification' command that
  5841   introduces the new constants axiomatically.
  5842 
  5843 * arith(_tac) is now able to generate counterexamples for reals as well.
  5844 
  5845 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5846 
  5847 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5848   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5849 
  5850 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5851   matrix theory to linear programming.
  5852 
  5853 * Unions and Intersections:
  5854   The latex output syntax of UN and INT has been changed
  5855   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5856   i.e. the index formulae has become a subscript.
  5857   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5858 
  5859 * Unions and Intersections over Intervals:
  5860   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5861   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5862   like in normal math, and corresponding versions for < and for intersection.
  5863 
  5864 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5865   lexicographic dictonary ordering has been added as "lexord".
  5866 
  5867 * ML: the legacy theory structures Int and List have been removed. They had
  5868   conflicted with ML Basis Library structures having the same names.
  5869 
  5870 * 'refute' command added to search for (finite) countermodels.  Only works
  5871   for a fragment of HOL.  The installation of an external SAT solver is
  5872   highly recommended.  See "HOL/Refute.thy" for details.
  5873 
  5874 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5875   formulae under an assignment of free variables to random values.
  5876   In contrast to 'refute', it can deal with inductive datatypes,
  5877   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5878   for examples.
  5879 
  5880 
  5881 *** HOLCF ***
  5882 
  5883 * Streams now come with concatenation and are part of the HOLCF image
  5884 
  5885 
  5886 
  5887 New in Isabelle2003 (May 2003)
  5888 ------------------------------
  5889 
  5890 *** General ***
  5891 
  5892 * Provers/simplifier:
  5893 
  5894   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5895     Assumptions are now subject to complete mutual simplification,
  5896     not just from left to right. The simplifier now preserves
  5897     the order of assumptions.
  5898 
  5899     Potential INCOMPATIBILITY:
  5900 
  5901     -- simp sometimes diverges where the old version did
  5902        not, e.g. invoking simp on the goal
  5903 
  5904         [| P (f x); y = x; f x = f y |] ==> Q
  5905 
  5906        now gives rise to the infinite reduction sequence
  5907 
  5908         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5909 
  5910        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5911        kind of problem.
  5912 
  5913     -- Tactics combining classical reasoner and simplification (such as auto)
  5914        are also affected by this change, because many of them rely on
  5915        simp. They may sometimes diverge as well or yield a different numbers
  5916        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5917        in case of problems. Sometimes subsequent calls to the classical
  5918        reasoner will fail because a preceeding call to the simplifier too
  5919        eagerly simplified the goal, e.g. deleted redundant premises.
  5920 
  5921   - The simplifier trace now shows the names of the applied rewrite rules
  5922 
  5923   - You can limit the number of recursive invocations of the simplifier
  5924     during conditional rewriting (where the simplifie tries to solve the
  5925     conditions before applying the rewrite rule):
  5926     ML "simp_depth_limit := n"
  5927     where n is an integer. Thus you can force termination where previously
  5928     the simplifier would diverge.
  5929 
  5930   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5931 
  5932   - No longer aborts on failed congruence proof.  Instead, the
  5933     congruence is ignored.
  5934 
  5935 * Pure: New generic framework for extracting programs from constructive
  5936   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5937   as HOL/Extraction for some case studies.
  5938 
  5939 * Pure: The main goal of the proof state is no longer shown by default, only
  5940 the subgoals. This behaviour is controlled by a new flag.
  5941    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5942 (ML: Proof.show_main_goal).
  5943 
  5944 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5945 rules whose conclusion matches subgoal 1:
  5946       PG menu: Isabelle/Isar -> Show me -> matching rules
  5947 The rules are ordered by how closely they match the subgoal.
  5948 In particular, rules that solve a subgoal outright are displayed first
  5949 (or rather last, the way they are printed).
  5950 (ML: ProofGeneral.print_intros())
  5951 
  5952 * Pure: New flag trace_unify_fail causes unification to print
  5953 diagnostic information (PG: in trace buffer) when it fails. This is
  5954 useful for figuring out why single step proofs like rule, erule or
  5955 assumption failed.
  5956 
  5957 * Pure: Locale specifications now produce predicate definitions
  5958 according to the body of text (covering assumptions modulo local
  5959 definitions); predicate "loc_axioms" covers newly introduced text,
  5960 while "loc" is cumulative wrt. all included locale expressions; the
  5961 latter view is presented only on export into the global theory
  5962 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5963 on the old view without predicates;
  5964 
  5965 * Pure: predefined locales "var" and "struct" are useful for sharing
  5966 parameters (as in CASL, for example); just specify something like
  5967 ``var x + var y + struct M'' as import;
  5968 
  5969 * Pure: improved thms_containing: proper indexing of facts instead of
  5970 raw theorems; check validity of results wrt. current name space;
  5971 include local facts of proof configuration (also covers active
  5972 locales), cover fixed variables in index; may use "_" in term
  5973 specification; an optional limit for the number of printed facts may
  5974 be given (the default is 40);
  5975 
  5976 * Pure: disallow duplicate fact bindings within new-style theory files
  5977 (batch-mode only);
  5978 
  5979 * Provers: improved induct method: assumptions introduced by case
  5980 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5981 the goal statement); "foo" still refers to all facts collectively;
  5982 
  5983 * Provers: the function blast.overloaded has been removed: all constants
  5984 are regarded as potentially overloaded, which improves robustness in exchange
  5985 for slight decrease in efficiency;
  5986 
  5987 * Provers/linorder: New generic prover for transitivity reasoning over
  5988 linear orders.  Note: this prover is not efficient!
  5989 
  5990 * Isar: preview of problems to finish 'show' now produce an error
  5991 rather than just a warning (in interactive mode);
  5992 
  5993 
  5994 *** HOL ***
  5995 
  5996 * arith(_tac)
  5997 
  5998  - Produces a counter example if it cannot prove a goal.
  5999    Note that the counter example may be spurious if the goal is not a formula
  6000    of quantifier-free linear arithmetic.
  6001    In ProofGeneral the counter example appears in the trace buffer.
  6002 
  6003  - Knows about div k and mod k where k is a numeral of type nat or int.
  6004 
  6005  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  6006    linear arithmetic fails. This takes account of quantifiers and divisibility.
  6007    Presburger arithmetic can also be called explicitly via presburger(_tac).
  6008 
  6009 * simp's arithmetic capabilities have been enhanced a bit: it now
  6010 takes ~= in premises into account (by performing a case split);
  6011 
  6012 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  6013 are distributed over a sum of terms;
  6014 
  6015 * New tactic "trans_tac" and method "trans" instantiate
  6016 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  6017 "<=", "<" and "=").
  6018 
  6019 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  6020 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  6021 
  6022 * 'typedef' command has new option "open" to suppress the set
  6023 definition;
  6024 
  6025 * functions Min and Max on finite sets have been introduced (theory
  6026 Finite_Set);
  6027 
  6028 * attribute [symmetric] now works for relations as well; it turns
  6029 (x,y) : R^-1 into (y,x) : R, and vice versa;
  6030 
  6031 * induct over a !!-quantified statement (say !!x1..xn):
  6032   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  6033 
  6034 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  6035 %x. None. Warning: empty_def now refers to the previously hidden definition
  6036 of the empty set.
  6037 
  6038 * Algebra: formalization of classical algebra.  Intended as base for
  6039 any algebraic development in Isabelle.  Currently covers group theory
  6040 (up to Sylow's theorem) and ring theory (Universal Property of
  6041 Univariate Polynomials).  Contributions welcome;
  6042 
  6043 * GroupTheory: deleted, since its material has been moved to Algebra;
  6044 
  6045 * Complex: new directory of the complex numbers with numeric constants,
  6046 nonstandard complex numbers, and some complex analysis, standard and
  6047 nonstandard (Jacques Fleuriot);
  6048 
  6049 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  6050 
  6051 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  6052 Fleuriot);
  6053 
  6054 * Real/HahnBanach: updated and adapted to locales;
  6055 
  6056 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  6057 Gray and Kramer);
  6058 
  6059 * UNITY: added the Meier-Sanders theory of progress sets;
  6060 
  6061 * MicroJava: bytecode verifier and lightweight bytecode verifier
  6062 as abstract algorithms, instantiated to the JVM;
  6063 
  6064 * Bali: Java source language formalization. Type system, operational
  6065 semantics, axiomatic semantics. Supported language features:
  6066 classes, interfaces, objects,virtual methods, static methods,
  6067 static/instance fields, arrays, access modifiers, definite
  6068 assignment, exceptions.
  6069 
  6070 
  6071 *** ZF ***
  6072 
  6073 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  6074 universe, etc.);
  6075 
  6076 * Main ZF: virtually all theories converted to new-style format;
  6077 
  6078 
  6079 *** ML ***
  6080 
  6081 * Pure: Tactic.prove provides sane interface for internal proofs;
  6082 omits the infamous "standard" operation, so this is more appropriate
  6083 than prove_goalw_cterm in many situations (e.g. in simprocs);
  6084 
  6085 * Pure: improved error reporting of simprocs;
  6086 
  6087 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  6088 up simprocs;
  6089 
  6090 
  6091 *** Document preparation ***
  6092 
  6093 * uses \par instead of \\ for line breaks in theory text. This may
  6094 shift some page breaks in large documents. To get the old behaviour
  6095 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  6096 
  6097 * minimized dependencies of isabelle.sty and isabellesym.sty on
  6098 other packages
  6099 
  6100 * \<euro> now needs package babel/greek instead of marvosym (which
  6101 broke \Rightarrow)
  6102 
  6103 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  6104 textcomp package)
  6105 
  6106 
  6107 
  6108 New in Isabelle2002 (March 2002)
  6109 --------------------------------
  6110 
  6111 *** Document preparation ***
  6112 
  6113 * greatly simplified document preparation setup, including more
  6114 graceful interpretation of isatool usedir -i/-d/-D options, and more
  6115 instructive isatool mkdir; users should basically be able to get
  6116 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  6117 users may run a separate document processing stage manually like this:
  6118 "isatool usedir -D output HOL Test && isatool document Test/output";
  6119 
  6120 * theory dependency graph may now be incorporated into documents;
  6121 isatool usedir -g true will produce session_graph.eps/.pdf for use
  6122 with \includegraphics of LaTeX;
  6123 
  6124 * proper spacing of consecutive markup elements, especially text
  6125 blocks after section headings;
  6126 
  6127 * support bold style (for single symbols only), input syntax is like
  6128 this: "\<^bold>\<alpha>" or "\<^bold>A";
  6129 
  6130 * \<bullet> is now output as bold \cdot by default, which looks much
  6131 better in printed text;
  6132 
  6133 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  6134 note that these symbols are currently unavailable in Proof General /
  6135 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  6136 
  6137 * isatool latex no longer depends on changed TEXINPUTS, instead
  6138 isatool document copies the Isabelle style files to the target
  6139 location;
  6140 
  6141 
  6142 *** Isar ***
  6143 
  6144 * Pure/Provers: improved proof by cases and induction;
  6145   - 'case' command admits impromptu naming of parameters (such as
  6146     "case (Suc n)");
  6147   - 'induct' method divinates rule instantiation from the inductive
  6148     claim; no longer requires excessive ?P bindings for proper
  6149     instantiation of cases;
  6150   - 'induct' method properly enumerates all possibilities of set/type
  6151     rules; as a consequence facts may be also passed through *type*
  6152     rules without further ado;
  6153   - 'induct' method now derives symbolic cases from the *rulified*
  6154     rule (before it used to rulify cases stemming from the internal
  6155     atomized version); this means that the context of a non-atomic
  6156     statement becomes is included in the hypothesis, avoiding the
  6157     slightly cumbersome show "PROP ?case" form;
  6158   - 'induct' may now use elim-style induction rules without chaining
  6159     facts, using ``missing'' premises from the goal state; this allows
  6160     rules stemming from inductive sets to be applied in unstructured
  6161     scripts, while still benefitting from proper handling of non-atomic
  6162     statements; NB: major inductive premises need to be put first, all
  6163     the rest of the goal is passed through the induction;
  6164   - 'induct' proper support for mutual induction involving non-atomic
  6165     rule statements (uses the new concept of simultaneous goals, see
  6166     below);
  6167   - append all possible rule selections, but only use the first
  6168     success (no backtracking);
  6169   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  6170   - undeclared rule case names default to numbers 1, 2, 3, ...;
  6171   - added 'print_induct_rules' (covered by help item in recent Proof
  6172     General versions);
  6173   - moved induct/cases attributes to Pure, methods to Provers;
  6174   - generic method setup instantiated for FOL and HOL;
  6175 
  6176 * Pure: support multiple simultaneous goal statements, for example
  6177 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  6178 meta-level mechanism, this acts as if several individual goals had
  6179 been stated separately; in particular common proof methods need to be
  6180 repeated in order to cover all claims; note that a single elimination
  6181 step is *not* sufficient to establish the two conjunctions, so this
  6182 fails:
  6183 
  6184   assume "A & B" then have A and B ..   (*".." fails*)
  6185 
  6186 better use "obtain" in situations as above; alternative refer to
  6187 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  6188 
  6189 * Pure: proper integration with ``locales''; unlike the original
  6190 version by Florian Kammller, Isar locales package high-level proof
  6191 contexts rather than raw logical ones (e.g. we admit to include
  6192 attributes everywhere); operations on locales include merge and
  6193 rename; support for implicit arguments (``structures''); simultaneous
  6194 type-inference over imports and text; see also HOL/ex/Locales.thy for
  6195 some examples;
  6196 
  6197 * Pure: the following commands have been ``localized'', supporting a
  6198 target locale specification "(in name)": 'lemma', 'theorem',
  6199 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  6200 stored both within the locale and at the theory level (exported and
  6201 qualified by the locale name);
  6202 
  6203 * Pure: theory goals may now be specified in ``long'' form, with
  6204 ad-hoc contexts consisting of arbitrary locale elements. for example
  6205 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  6206 definitions may be given, too); the result is a meta-level rule with
  6207 the context elements being discharged in the obvious way;
  6208 
  6209 * Pure: new proof command 'using' allows to augment currently used
  6210 facts after a goal statement ('using' is syntactically analogous to
  6211 'apply', but acts on the goal's facts only); this allows chained facts
  6212 to be separated into parts given before and after a claim, as in
  6213 ``from a and b have C using d and e <proof>'';
  6214 
  6215 * Pure: renamed "antecedent" case to "rule_context";
  6216 
  6217 * Pure: new 'judgment' command records explicit information about the
  6218 object-logic embedding (used by several tools internally); no longer
  6219 use hard-wired "Trueprop";
  6220 
  6221 * Pure: added 'corollary' command;
  6222 
  6223 * Pure: fixed 'token_translation' command;
  6224 
  6225 * Pure: removed obsolete 'exported' attribute;
  6226 
  6227 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  6228 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  6229 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  6230 
<