NEWS
author bulwahn
Wed Aug 03 16:08:02 2011 +0200 (2011-08-03)
changeset 44023 3e5f8cc666db
parent 44019 ee784502aed5
child 44027 d01b3f045111
permissions -rw-r--r--
NEWS
     1 Isabelle NEWS -- history user-relevant changes
     2 ==============================================
     3 
     4 New in this Isabelle version
     5 ----------------------------
     6 
     7 *** General ***
     8 
     9 * Theory loader: source files are identified by content via SHA1
    10 digests.  Discontinued former path/modtime identification and optional
    11 ISABELLE_FILE_IDENT plugin scripts.
    12 
    13 * Parallelization of nested Isar proofs is subject to
    14 Goal.parallel_proofs_threshold (default 100).  See also isabelle
    15 usedir option -Q.
    16 
    17 * Discontinued support for Poly/ML 5.2, which was the last version
    18 without proper multithreading and TimeLimit implementation.
    19 
    20 * Discontinued old lib/scripts/polyml-platform, which has been
    21 obsolete since Isabelle2009-2.
    22 
    23 * Theory loader: source files are exclusively located via the master
    24 directory of each theory node (where the .thy file itself resides).
    25 The global load path (such as src/HOL/Library) has been discontinued.
    26 Note that the path element ~~ may be used to reference theories in the
    27 Isabelle home folder -- for instance, "~~/src/HOL/Library/FuncSet".
    28 INCOMPATIBILITY.
    29 
    30 * Various optional external tools are referenced more robustly and
    31 uniformly by explicit Isabelle settings as follows:
    32 
    33   ISABELLE_CSDP   (formerly CSDP_EXE)
    34   ISABELLE_GHC    (formerly EXEC_GHC or GHC_PATH)
    35   ISABELLE_OCAML  (formerly EXEC_OCAML)
    36   ISABELLE_SWIPL  (formerly EXEC_SWIPL)
    37   ISABELLE_YAP    (formerly EXEC_YAP)
    38 
    39 Note that automated detection from the file-system or search path has
    40 been discontinued.  INCOMPATIBILITY.
    41 
    42 * Name space: former unsynchronized references are now proper
    43 configuration options, with more conventional names:
    44 
    45   long_names   ~> names_long
    46   short_names  ~> names_short
    47   unique_names ~> names_unique
    48 
    49 Minor INCOMPATIBILITY, need to declare options in context like this:
    50 
    51   declare [[names_unique = false]]
    52 
    53 * Literal facts `prop` may contain dummy patterns, e.g. `_ = _`.  Note
    54 that the result needs to be unique, which means fact specifications
    55 may have to be refined after enriching a proof context.
    56 
    57 * Isabelle/Isar reference manual provides more formal references in
    58 syntax diagrams.
    59 
    60 
    61 *** HOL ***
    62 
    63 * 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 More consistent and less misunderstandable names:
    71   INFI_def ~> INF_def
    72   SUPR_def ~> SUP_def
    73   le_SUPI ~> le_SUP_I
    74   le_SUPI2 ~> le_SUP_I2
    75   le_INFI ~> le_INF_I
    76   INFI_bool_eq ~> INF_bool_eq
    77   SUPR_bool_eq ~> SUP_bool_eq
    78   INFI_apply ~> INF_apply
    79   SUPR_apply ~> SUP_apply
    80 INCOMPATIBILITY.
    81 
    82 * Theorem collections ball_simps and bex_simps do not contain theorems referring
    83 to UNION any longer;  these have been moved to collection UN_ball_bex_simps.
    84 INCOMPATIBILITY.
    85 
    86 * Archimedean_Field.thy:
    87     floor now is defined as parameter of a separate type class floor_ceiling.
    88  
    89 * Finite_Set.thy: more coherent development of fold_set locales:
    90 
    91     locale fun_left_comm ~> locale comp_fun_commute
    92     locale fun_left_comm_idem ~> locale comp_fun_idem
    93     
    94 Both use point-free characterisation; interpretation proofs may need adjustment.
    95 INCOMPATIBILITY.
    96 
    97 * Code generation:
    98   - theory Library/Code_Char_ord provides native ordering of characters
    99     in the target language.
   100   - commands code_module and code_library are legacy, use export_code instead. 
   101   - method evaluation is legacy, use method eval instead.
   102   - legacy evaluator "SML" is deactivated by default. To activate it, add the following
   103     line in your theory:
   104       setup {* Value.add_evaluator ("SML", Codegen.eval_term) *}
   105  
   106 * Declare ext [intro] by default.  Rare INCOMPATIBILITY.
   107 
   108 * Nitpick:
   109   - Added "need" and "total_consts" options.
   110   - Reintroduced "show_skolems" option by popular demand.
   111   - Renamed attribute: nitpick_def ~> nitpick_unfold.
   112     INCOMPATIBILITY.
   113 
   114 * Sledgehammer:
   115   - sledgehammer available_provers ~> sledgehammer supported_provers.
   116     INCOMPATIBILITY.
   117   - Added support for SNARK and ToFoF-E on SystemOnTPTP and for simply typed
   118     TPTP problems (TFF).
   119   - Added "preplay_timeout", "slicing", "type_enc", "sound", "max_mono_iters",
   120     and "max_new_mono_instances" options.
   121   - Removed "explicit_apply" and "full_types" options as well as "Full Types"
   122     Proof General menu item. INCOMPATIBILITY.
   123 
   124 * Metis:
   125   - Removed "metisF" -- use "metis" instead. INCOMPATIBILITY.
   126   - Obsoleted "metisFT" -- use "metis (full_types)" instead. INCOMPATIBILITY.
   127 
   128 * "try":
   129   - Renamed "try_methods" and added "simp:", "intro:", "dest:", and "elim:"
   130     options. INCOMPATIBILITY.
   131   - Introduced "try" that not only runs "try_methods" but also "solve_direct",
   132     "sledgehammer", "quickcheck", and "nitpick".
   133 
   134 * Quickcheck:
   135   - Added "eval" option to evaluate terms for the found counterexample
   136     (currently only supported by the default (exhaustive) tester)
   137   - Added post-processing of terms to obtain readable counterexamples
   138     (currently only supported by the default (exhaustive) tester)
   139   - New counterexample generator quickcheck[narrowing] enables
   140     narrowing-based testing.
   141     It requires that the Glasgow Haskell compiler is installed and
   142     its location is known to Isabelle with the environment variable
   143     ISABELLE_GHC.
   144   - Removed quickcheck tester "SML" based on the SML code generator
   145     from HOL-Library
   146 
   147 * Function package: discontinued option "tailrec".
   148 INCOMPATIBILITY. Use partial_function instead.
   149 
   150 * HOL-Probability:
   151   - Caratheodory's extension lemma is now proved for ring_of_sets.
   152   - Infinite products of probability measures are now available.
   153   - Use extended reals instead of positive extended reals.
   154     INCOMPATIBILITY.
   155 
   156 * Old recdef package has been moved to Library/Old_Recdef.thy, where it
   157 must be loaded explicitly.  INCOMPATIBILITY.
   158 
   159 * Well-founded recursion combinator "wfrec" has been moved to
   160 Library/Wfrec.thy. INCOMPATIBILITY.
   161 
   162 * Theory Library/Nat_Infinity has been renamed to Library/Extended_Nat.
   163 The names of the following types and constants have changed:
   164   inat (type) ~> enat
   165   Fin         ~> enat
   166   Infty       ~> infinity (overloaded)
   167   iSuc        ~> eSuc
   168   the_Fin     ~> the_enat
   169 Every theorem name containing "inat", "Fin", "Infty", or "iSuc" has
   170 been renamed accordingly.
   171 
   172 
   173 *** Document preparation ***
   174 
   175 * Discontinued special treatment of hard tabulators, which are better
   176 avoided in the first place.  Implicit tab-width is 1.
   177 
   178 * Antiquotation @{rail} layouts railroad syntax diagrams, see also
   179 isar-ref manual.
   180 
   181 * Antiquotation @{value} evaluates the given term and presents its result.
   182 
   183 * Localized \isabellestyle switch can be used within blocks or groups
   184 like this:
   185 
   186   \isabellestyle{it}  %preferred default
   187   {\isabellestylett @{text "typewriter stuff"}}
   188 
   189 * New term style "isub" as ad-hoc conversion of variables x1, y23 into
   190 subscripted form x\<^isub>1, y\<^isub>2\<^isub>3.
   191 
   192 * Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
   193 (e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).
   194 
   195 
   196 *** ML ***
   197 
   198 * The inner syntax of sort/type/term/prop supports inlined YXML
   199 representations within quoted string tokens.  By encoding logical
   200 entities via Term_XML (in ML or Scala) concrete syntax can be
   201 bypassed, which is particularly useful for producing bits of text
   202 under external program control.
   203 
   204 * Antiquotations for ML and document preparation are managed as theory
   205 data, which requires explicit setup.
   206 
   207 * Isabelle_Process.is_active allows tools to check if the official
   208 process wrapper is running (Isabelle/Scala/jEdit) or the old TTY loop
   209 (better known as Proof General).
   210 
   211 * Structure Proof_Context follows standard naming scheme.  Old
   212 ProofContext is still available for some time as legacy alias.
   213 
   214 * Structure Timing provides various operations for timing; supersedes
   215 former start_timing/end_timing etc.
   216 
   217 * Path.print is the official way to show file-system paths to users
   218 (including quotes etc.).
   219 
   220 * Inner syntax: identifiers in parse trees of generic categories
   221 "logic", "aprop", "idt" etc. carry position information (disguised as
   222 type constraints).  Occasional INCOMPATIBILITY with non-compliant
   223 translations that choke on unexpected type constraints.  Positions can
   224 be stripped in ML translations via Syntax.strip_positions /
   225 Syntax.strip_positions_ast, or via the syntax constant
   226 "_strip_positions" within parse trees.  As last resort, positions can
   227 be disabled via the configuration option Syntax.positions, which is
   228 called "syntax_positions" in Isar attribute syntax.
   229 
   230 * Discontinued special status of various ML structures that contribute
   231 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
   232 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
   233 refer directly to Ast.Constant, Lexicon.is_identifier,
   234 Syntax_Trans.mk_binder_tr etc.
   235 
   236 * Typed print translation: discontinued show_sorts argument, which is
   237 already available via context of "advanced" translation.
   238 
   239 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
   240 goal states; body tactic needs to address all subgoals uniformly.
   241 
   242 * Slightly more special eq_list/eq_set, with shortcut involving
   243 pointer equality (assumes that eq relation is reflexive).
   244 
   245 * Classical tactics use proper Proof.context instead of historic types
   246 claset/clasimpset.  Old-style declarations like addIs, addEs, addDs
   247 operate directly on Proof.context.  Raw type claset retains its use as
   248 snapshot of the classical context, which can be recovered via
   249 (put_claset HOL_cs) etc.  Type clasimpset has been discontinued.
   250 INCOMPATIBILITY, classical tactics and derived proof methods require
   251 proper Proof.context.
   252 
   253 * Scala layer provides JVM method invocation service for static
   254 methods of type (String)String, see Invoke_Scala.method in ML.
   255 For example:
   256 
   257   Invoke_Scala.method "java.lang.System.getProperty" "java.home"
   258 
   259 
   260 
   261 New in Isabelle2011 (January 2011)
   262 ----------------------------------
   263 
   264 *** General ***
   265 
   266 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
   267 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
   268 useful tooltips and hyperlinks produced from its static analysis.  The
   269 bundled component provides an executable Isabelle tool that can be run
   270 like this:
   271 
   272   Isabelle2011/bin/isabelle jedit
   273 
   274 * Significantly improved Isabelle/Isar implementation manual.
   275 
   276 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
   277 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
   278 while the default heap location within that directory lacks that extra
   279 suffix.  This isolates multiple Isabelle installations from each
   280 other, avoiding problems with old settings in new versions.
   281 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
   282 
   283 * Source files are always encoded as UTF-8, instead of old-fashioned
   284 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
   285 the following package declarations:
   286 
   287   \usepackage[utf8]{inputenc}
   288   \usepackage{textcomp}
   289 
   290 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
   291 a Unicode character is treated as a single symbol, not a sequence of
   292 non-ASCII bytes as before.  Since Isabelle/ML string literals may
   293 contain symbols without further backslash escapes, Unicode can now be
   294 used here as well.  Recall that Symbol.explode in ML provides a
   295 consistent view on symbols, while raw explode (or String.explode)
   296 merely give a byte-oriented representation.
   297 
   298 * Theory loader: source files are primarily located via the master
   299 directory of each theory node (where the .thy file itself resides).
   300 The global load path is still partially available as legacy feature.
   301 Minor INCOMPATIBILITY due to subtle change in file lookup: use
   302 explicit paths, relatively to the theory.
   303 
   304 * Special treatment of ML file names has been discontinued.
   305 Historically, optional extensions .ML or .sml were added on demand --
   306 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
   307 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
   308 
   309 * Various options that affect pretty printing etc. are now properly
   310 handled within the context via configuration options, instead of
   311 unsynchronized references or print modes.  There are both ML Config.T
   312 entities and Isar declaration attributes to access these.
   313 
   314   ML (Config.T)                 Isar (attribute)
   315 
   316   eta_contract                  eta_contract
   317   show_brackets                 show_brackets
   318   show_sorts                    show_sorts
   319   show_types                    show_types
   320   show_question_marks           show_question_marks
   321   show_consts                   show_consts
   322   show_abbrevs                  show_abbrevs
   323 
   324   Syntax.ast_trace              syntax_ast_trace
   325   Syntax.ast_stat               syntax_ast_stat
   326   Syntax.ambiguity_level        syntax_ambiguity_level
   327 
   328   Goal_Display.goals_limit      goals_limit
   329   Goal_Display.show_main_goal   show_main_goal
   330 
   331   Method.rule_trace             rule_trace
   332 
   333   Thy_Output.display            thy_output_display
   334   Thy_Output.quotes             thy_output_quotes
   335   Thy_Output.indent             thy_output_indent
   336   Thy_Output.source             thy_output_source
   337   Thy_Output.break              thy_output_break
   338 
   339 Note that corresponding "..._default" references in ML may only be
   340 changed globally at the ROOT session setup, but *not* within a theory.
   341 The option "show_abbrevs" supersedes the former print mode
   342 "no_abbrevs" with inverted meaning.
   343 
   344 * More systematic naming of some configuration options.
   345 INCOMPATIBILITY.
   346 
   347   trace_simp  ~>  simp_trace
   348   debug_simp  ~>  simp_debug
   349 
   350 * Support for real valued configuration options, using simplistic
   351 floating-point notation that coincides with the inner syntax for
   352 float_token.
   353 
   354 * Support for real valued preferences (with approximative PGIP type):
   355 front-ends need to accept "pgint" values in float notation.
   356 INCOMPATIBILITY.
   357 
   358 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
   359 DejaVu Sans.
   360 
   361 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   362 
   363 
   364 *** Pure ***
   365 
   366 * Command 'type_synonym' (with single argument) replaces somewhat
   367 outdated 'types', which is still available as legacy feature for some
   368 time.
   369 
   370 * Command 'nonterminal' (with 'and' separated list of arguments)
   371 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
   372 
   373 * Command 'notepad' replaces former 'example_proof' for
   374 experimentation in Isar without any result.  INCOMPATIBILITY.
   375 
   376 * Locale interpretation commands 'interpret' and 'sublocale' accept
   377 lists of equations to map definitions in a locale to appropriate
   378 entities in the context of the interpretation.  The 'interpretation'
   379 command already provided this functionality.
   380 
   381 * Diagnostic command 'print_dependencies' prints the locale instances
   382 that would be activated if the specified expression was interpreted in
   383 the current context.  Variant "print_dependencies!" assumes a context
   384 without interpretations.
   385 
   386 * Diagnostic command 'print_interps' prints interpretations in proofs
   387 in addition to interpretations in theories.
   388 
   389 * Discontinued obsolete 'global' and 'local' commands to manipulate
   390 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
   391 Sign.root_path and Sign.local_path may be applied directly where this
   392 feature is still required for historical reasons.
   393 
   394 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
   395 'definition' instead.
   396 
   397 * The "prems" fact, which refers to the accidental collection of
   398 foundational premises in the context, is now explicitly marked as
   399 legacy feature and will be discontinued soon.  Consider using "assms"
   400 of the head statement or reference facts by explicit names.
   401 
   402 * Document antiquotations @{class} and @{type} print classes and type
   403 constructors.
   404 
   405 * Document antiquotation @{file} checks file/directory entries within
   406 the local file system.
   407 
   408 
   409 *** HOL ***
   410 
   411 * Coercive subtyping: functions can be declared as coercions and type
   412 inference will add them as necessary upon input of a term.  Theory
   413 Complex_Main declares real :: nat => real and real :: int => real as
   414 coercions. A coercion function f is declared like this:
   415 
   416   declare [[coercion f]]
   417 
   418 To lift coercions through type constructors (e.g. from nat => real to
   419 nat list => real list), map functions can be declared, e.g.
   420 
   421   declare [[coercion_map map]]
   422 
   423 Currently coercion inference is activated only in theories including
   424 real numbers, i.e. descendants of Complex_Main.  This is controlled by
   425 the configuration option "coercion_enabled", e.g. it can be enabled in
   426 other theories like this:
   427 
   428   declare [[coercion_enabled]]
   429 
   430 * Command 'partial_function' provides basic support for recursive
   431 function definitions over complete partial orders.  Concrete instances
   432 are provided for i) the option type, ii) tail recursion on arbitrary
   433 types, and iii) the heap monad of Imperative_HOL.  See
   434 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
   435 for examples.
   436 
   437 * Function package: f.psimps rules are no longer implicitly declared
   438 as [simp].  INCOMPATIBILITY.
   439 
   440 * Datatype package: theorems generated for executable equality (class
   441 "eq") carry proper names and are treated as default code equations.
   442 
   443 * Inductive package: now offers command 'inductive_simps' to
   444 automatically derive instantiated and simplified equations for
   445 inductive predicates, similar to 'inductive_cases'.
   446 
   447 * Command 'enriched_type' allows to register properties of the
   448 functorial structure of types.
   449 
   450 * Improved infrastructure for term evaluation using code generator
   451 techniques, in particular static evaluation conversions.
   452 
   453 * Code generator: Scala (2.8 or higher) has been added to the target
   454 languages.
   455 
   456 * Code generator: globbing constant expressions "*" and "Theory.*"
   457 have been replaced by the more idiomatic "_" and "Theory._".
   458 INCOMPATIBILITY.
   459 
   460 * Code generator: export_code without explicit file declaration prints
   461 to standard output.  INCOMPATIBILITY.
   462 
   463 * Code generator: do not print function definitions for case
   464 combinators any longer.
   465 
   466 * Code generator: simplification with rules determined with
   467 src/Tools/Code/code_simp.ML and method "code_simp".
   468 
   469 * Code generator for records: more idiomatic representation of record
   470 types.  Warning: records are not covered by ancient SML code
   471 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
   472 rep_datatype declaration helps to succeed then:
   473 
   474   record 'a foo = ...
   475   ...
   476   rep_datatype foo_ext ...
   477 
   478 * Records: logical foundation type for records does not carry a
   479 '_type' suffix any longer (obsolete due to authentic syntax).
   480 INCOMPATIBILITY.
   481 
   482 * Quickcheck now by default uses exhaustive testing instead of random
   483 testing.  Random testing can be invoked by "quickcheck [random]",
   484 exhaustive testing by "quickcheck [exhaustive]".
   485 
   486 * Quickcheck instantiates polymorphic types with small finite
   487 datatypes by default. This enables a simple execution mechanism to
   488 handle quantifiers and function equality over the finite datatypes.
   489 
   490 * Quickcheck random generator has been renamed from "code" to
   491 "random".  INCOMPATIBILITY.
   492 
   493 * Quickcheck now has a configurable time limit which is set to 30
   494 seconds by default. This can be changed by adding [timeout = n] to the
   495 quickcheck command. The time limit for Auto Quickcheck is still set
   496 independently.
   497 
   498 * Quickcheck in locales considers interpretations of that locale for
   499 counter example search.
   500 
   501 * Sledgehammer:
   502   - Added "smt" and "remote_smt" provers based on the "smt" proof
   503     method. See the Sledgehammer manual for details ("isabelle doc
   504     sledgehammer").
   505   - Renamed commands:
   506     sledgehammer atp_info ~> sledgehammer running_provers
   507     sledgehammer atp_kill ~> sledgehammer kill_provers
   508     sledgehammer available_atps ~> sledgehammer available_provers
   509     INCOMPATIBILITY.
   510   - Renamed options:
   511     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
   512     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
   513     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
   514     (and "ms" and "min" are no longer supported)
   515     INCOMPATIBILITY.
   516 
   517 * Nitpick:
   518   - Renamed options:
   519     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
   520     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
   521     INCOMPATIBILITY.
   522   - Added support for partial quotient types.
   523   - Added local versions of the "Nitpick.register_xxx" functions.
   524   - Added "whack" option.
   525   - Allow registration of quotient types as codatatypes.
   526   - Improved "merge_type_vars" option to merge more types.
   527   - Removed unsound "fast_descrs" option.
   528   - Added custom symmetry breaking for datatypes, making it possible to reach
   529     higher cardinalities.
   530   - Prevent the expansion of too large definitions.
   531 
   532 * Proof methods "metis" and "meson" now have configuration options
   533 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
   534 to diagnose these tools. E.g.
   535 
   536     using [[metis_trace = true]]
   537 
   538 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
   539 manually as command 'solve_direct'.
   540 
   541 * The default SMT solver Z3 must be enabled explicitly (due to
   542 licensing issues) by setting the environment variable
   543 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
   544 commercial applications, the SMT solver CVC3 is provided as fall-back;
   545 changing the SMT solver is done via the configuration option
   546 "smt_solver".
   547 
   548 * Remote SMT solvers need to be referred to by the "remote_" prefix,
   549 i.e. "remote_cvc3" and "remote_z3".
   550 
   551 * Added basic SMT support for datatypes, records, and typedefs using
   552 the oracle mode (no proofs).  Direct support of pairs has been dropped
   553 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
   554 support for a similar behavior).  Minor INCOMPATIBILITY.
   555 
   556 * Changed SMT configuration options:
   557   - Renamed:
   558     z3_proofs ~> smt_oracle (with inverted meaning)
   559     z3_trace_assms ~> smt_trace_used_facts
   560     INCOMPATIBILITY.
   561   - Added:
   562     smt_verbose
   563     smt_random_seed
   564     smt_datatypes
   565     smt_infer_triggers
   566     smt_monomorph_limit
   567     cvc3_options
   568     remote_cvc3_options
   569     remote_z3_options
   570     yices_options
   571 
   572 * Boogie output files (.b2i files) need to be declared in the theory
   573 header.
   574 
   575 * Simplification procedure "list_to_set_comprehension" rewrites list
   576 comprehensions applied to List.set to set comprehensions.  Occasional
   577 INCOMPATIBILITY, may be deactivated like this:
   578 
   579   declare [[simproc del: list_to_set_comprehension]]
   580 
   581 * Removed old version of primrec package.  INCOMPATIBILITY.
   582 
   583 * Removed simplifier congruence rule of "prod_case", as has for long
   584 been the case with "split".  INCOMPATIBILITY.
   585 
   586 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
   587 
   588 * Removed [split_format ... and ... and ...] version of
   589 [split_format].  Potential INCOMPATIBILITY.
   590 
   591 * Predicate "sorted" now defined inductively, with nice induction
   592 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
   593 
   594 * Constant "contents" renamed to "the_elem", to free the generic name
   595 contents for other uses.  INCOMPATIBILITY.
   596 
   597 * Renamed class eq and constant eq (for code generation) to class
   598 equal and constant equal, plus renaming of related facts and various
   599 tuning.  INCOMPATIBILITY.
   600 
   601 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
   602 
   603 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
   604 INCOMPATIBILITY.
   605 
   606 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
   607 avoid confusion with finite sets.  INCOMPATIBILITY.
   608 
   609 * Abandoned locales equiv, congruent and congruent2 for equivalence
   610 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
   611 for congruent(2)).
   612 
   613 * Some previously unqualified names have been qualified:
   614 
   615   types
   616     bool ~> HOL.bool
   617     nat ~> Nat.nat
   618 
   619   constants
   620     Trueprop ~> HOL.Trueprop
   621     True ~> HOL.True
   622     False ~> HOL.False
   623     op & ~> HOL.conj
   624     op | ~> HOL.disj
   625     op --> ~> HOL.implies
   626     op = ~> HOL.eq
   627     Not ~> HOL.Not
   628     The ~> HOL.The
   629     All ~> HOL.All
   630     Ex ~> HOL.Ex
   631     Ex1 ~> HOL.Ex1
   632     Let ~> HOL.Let
   633     If ~> HOL.If
   634     Ball ~> Set.Ball
   635     Bex ~> Set.Bex
   636     Suc ~> Nat.Suc
   637     Pair ~> Product_Type.Pair
   638     fst ~> Product_Type.fst
   639     snd ~> Product_Type.snd
   640     curry ~> Product_Type.curry
   641     op : ~> Set.member
   642     Collect ~> Set.Collect
   643 
   644 INCOMPATIBILITY.
   645 
   646 * More canonical naming convention for some fundamental definitions:
   647 
   648     bot_bool_eq ~> bot_bool_def
   649     top_bool_eq ~> top_bool_def
   650     inf_bool_eq ~> inf_bool_def
   651     sup_bool_eq ~> sup_bool_def
   652     bot_fun_eq  ~> bot_fun_def
   653     top_fun_eq  ~> top_fun_def
   654     inf_fun_eq  ~> inf_fun_def
   655     sup_fun_eq  ~> sup_fun_def
   656 
   657 INCOMPATIBILITY.
   658 
   659 * More stylized fact names:
   660 
   661   expand_fun_eq ~> fun_eq_iff
   662   expand_set_eq ~> set_eq_iff
   663   set_ext       ~> set_eqI
   664   nat_number    ~> eval_nat_numeral
   665 
   666 INCOMPATIBILITY.
   667 
   668 * Refactoring of code-generation specific operations in theory List:
   669 
   670   constants
   671     null ~> List.null
   672 
   673   facts
   674     mem_iff ~> member_def
   675     null_empty ~> null_def
   676 
   677 INCOMPATIBILITY.  Note that these were not supposed to be used
   678 regularly unless for striking reasons; their main purpose was code
   679 generation.
   680 
   681 Various operations from the Haskell prelude are used for generating
   682 Haskell code.
   683 
   684 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
   685 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
   686 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
   687 
   688 * Abolished some non-alphabetic type names: "prod" and "sum" replace
   689 "*" and "+" respectively.  INCOMPATIBILITY.
   690 
   691 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
   692 "Sum_Type.Plus" instead.
   693 
   694 * Constant "split" has been merged with constant "prod_case"; names of
   695 ML functions, facts etc. involving split have been retained so far,
   696 though.  INCOMPATIBILITY.
   697 
   698 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
   699 instead.  INCOMPATIBILITY.
   700 
   701 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
   702 INCOMPATIBILITY.
   703 
   704 * Former theory Library/Enum is now part of the HOL-Main image.
   705 INCOMPATIBILITY: all constants of the Enum theory now have to be
   706 referred to by its qualified name.
   707 
   708   enum    ~>  Enum.enum
   709   nlists  ~>  Enum.nlists
   710   product ~>  Enum.product
   711 
   712 * Theory Library/Monad_Syntax provides do-syntax for monad types.
   713 Syntax in Library/State_Monad has been changed to avoid ambiguities.
   714 INCOMPATIBILITY.
   715 
   716 * Theory Library/SetsAndFunctions has been split into
   717 Library/Function_Algebras and Library/Set_Algebras; canonical names
   718 for instance definitions for functions; various improvements.
   719 INCOMPATIBILITY.
   720 
   721 * Theory Library/Multiset provides stable quicksort implementation of
   722 sort_key.
   723 
   724 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
   725 INCOMPATIBILITY.
   726 
   727 * Session Multivariate_Analysis: introduced a type class for euclidean
   728 space.  Most theorems are now stated in terms of euclidean spaces
   729 instead of finite cartesian products.
   730 
   731   types
   732     real ^ 'n ~>  'a::real_vector
   733               ~>  'a::euclidean_space
   734               ~>  'a::ordered_euclidean_space
   735         (depends on your needs)
   736 
   737   constants
   738      _ $ _        ~> _ $$ _
   739      \<chi> x. _  ~> \<chi>\<chi> x. _
   740      CARD('n)     ~> DIM('a)
   741 
   742 Also note that the indices are now natural numbers and not from some
   743 finite type. Finite cartesian products of euclidean spaces, products
   744 of euclidean spaces the real and complex numbers are instantiated to
   745 be euclidean_spaces.  INCOMPATIBILITY.
   746 
   747 * Session Probability: introduced pextreal as positive extended real
   748 numbers.  Use pextreal as value for measures.  Introduce the
   749 Radon-Nikodym derivative, product spaces and Fubini's theorem for
   750 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
   751 the integral in Multivariate Analysis.  INCOMPATIBILITY.
   752 
   753 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   754 INCOMPATIBILITY.
   755 
   756 * Session SPARK (with image HOL-SPARK) provides commands to load and
   757 prove verification conditions generated by the SPARK Ada program
   758 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
   759 
   760 
   761 *** HOL-Algebra ***
   762 
   763 * Theorems for additive ring operations (locale abelian_monoid and
   764 descendants) are generated by interpretation from their multiplicative
   765 counterparts.  Names (in particular theorem names) have the mandatory
   766 qualifier 'add'.  Previous theorem names are redeclared for
   767 compatibility.
   768 
   769 * Structure "int_ring" is now an abbreviation (previously a
   770 definition).  This fits more natural with advanced interpretations.
   771 
   772 
   773 *** HOLCF ***
   774 
   775 * The domain package now runs in definitional mode by default: The
   776 former command 'new_domain' is now called 'domain'.  To use the domain
   777 package in its original axiomatic mode, use 'domain (unsafe)'.
   778 INCOMPATIBILITY.
   779 
   780 * The new class "domain" is now the default sort.  Class "predomain"
   781 is an unpointed version of "domain". Theories can be updated by
   782 replacing sort annotations as shown below.  INCOMPATIBILITY.
   783 
   784   'a::type ~> 'a::countable
   785   'a::cpo  ~> 'a::predomain
   786   'a::pcpo ~> 'a::domain
   787 
   788 * The old type class "rep" has been superseded by class "domain".
   789 Accordingly, users of the definitional package must remove any
   790 "default_sort rep" declarations.  INCOMPATIBILITY.
   791 
   792 * The domain package (definitional mode) now supports unpointed
   793 predomain argument types, as long as they are marked 'lazy'. (Strict
   794 arguments must be in class "domain".) For example, the following
   795 domain definition now works:
   796 
   797   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
   798 
   799 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
   800 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
   801 'a option, and 'a list.  Additionally, it configures fixrec and the
   802 domain package to work with these types.  For example:
   803 
   804   fixrec isInl :: "('a + 'b) u -> tr"
   805     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
   806 
   807   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
   808 
   809 * The "(permissive)" option of fixrec has been replaced with a
   810 per-equation "(unchecked)" option. See
   811 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
   812 
   813 * The "bifinite" class no longer fixes a constant "approx"; the class
   814 now just asserts that such a function exists.  INCOMPATIBILITY.
   815 
   816 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
   817 defines an embedding of type 'a defl into udom by default; instances
   818 of "bifinite" and "domain" classes are available in
   819 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
   820 
   821 * The syntax "REP('a)" has been replaced with "DEFL('a)".
   822 
   823 * The predicate "directed" has been removed.  INCOMPATIBILITY.
   824 
   825 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
   826 
   827 * The function "cprod_map" has been renamed to "prod_map".
   828 INCOMPATIBILITY.
   829 
   830 * The monadic bind operator on each powerdomain has new binder syntax
   831 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
   832 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
   833 
   834 * The infix syntax for binary union on each powerdomain has changed
   835 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
   836 syntax.  INCOMPATIBILITY.
   837 
   838 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
   839 still supported as an input translation.
   840 
   841 * Renamed some theorems (the original names are also still available).
   842 
   843   expand_fun_below   ~> fun_below_iff
   844   below_fun_ext      ~> fun_belowI
   845   expand_cfun_eq     ~> cfun_eq_iff
   846   ext_cfun           ~> cfun_eqI
   847   expand_cfun_below  ~> cfun_below_iff
   848   below_cfun_ext     ~> cfun_belowI
   849   cont2cont_Rep_CFun ~> cont2cont_APP
   850 
   851 * The Abs and Rep functions for various types have changed names.
   852 Related theorem names have also changed to match. INCOMPATIBILITY.
   853 
   854   Rep_CFun  ~> Rep_cfun
   855   Abs_CFun  ~> Abs_cfun
   856   Rep_Sprod ~> Rep_sprod
   857   Abs_Sprod ~> Abs_sprod
   858   Rep_Ssum  ~> Rep_ssum
   859   Abs_Ssum  ~> Abs_ssum
   860 
   861 * Lemmas with names of the form *_defined_iff or *_strict_iff have
   862 been renamed to *_bottom_iff.  INCOMPATIBILITY.
   863 
   864 * Various changes to bisimulation/coinduction with domain package:
   865 
   866   - Definitions of "bisim" constants no longer mention definedness.
   867   - With mutual recursion, "bisim" predicate is now curried.
   868   - With mutual recursion, each type gets a separate coind theorem.
   869   - Variable names in bisim_def and coinduct rules have changed.
   870 
   871 INCOMPATIBILITY.
   872 
   873 * Case combinators generated by the domain package for type "foo" are
   874 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
   875 
   876 * Several theorems have been renamed to more accurately reflect the
   877 names of constants and types involved.  INCOMPATIBILITY.
   878 
   879   thelub_const    ~> lub_const
   880   lub_const       ~> is_lub_const
   881   thelubI         ~> lub_eqI
   882   is_lub_lub      ~> is_lubD2
   883   lubI            ~> is_lub_lub
   884   unique_lub      ~> is_lub_unique
   885   is_ub_lub       ~> is_lub_rangeD1
   886   lub_bin_chain   ~> is_lub_bin_chain
   887   lub_fun         ~> is_lub_fun
   888   thelub_fun      ~> lub_fun
   889   thelub_cfun     ~> lub_cfun
   890   thelub_Pair     ~> lub_Pair
   891   lub_cprod       ~> is_lub_prod
   892   thelub_cprod    ~> lub_prod
   893   minimal_cprod   ~> minimal_prod
   894   inst_cprod_pcpo ~> inst_prod_pcpo
   895   UU_I            ~> bottomI
   896   compact_UU      ~> compact_bottom
   897   deflation_UU    ~> deflation_bottom
   898   finite_deflation_UU ~> finite_deflation_bottom
   899 
   900 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
   901 
   902   sq_ord_less_eq_trans ~> below_eq_trans
   903   sq_ord_eq_less_trans ~> eq_below_trans
   904   refl_less            ~> below_refl
   905   trans_less           ~> below_trans
   906   antisym_less         ~> below_antisym
   907   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
   908   box_less             ~> box_below
   909   rev_trans_less       ~> rev_below_trans
   910   not_less2not_eq      ~> not_below2not_eq
   911   less_UU_iff          ~> below_UU_iff
   912   flat_less_iff        ~> flat_below_iff
   913   adm_less             ~> adm_below
   914   adm_not_less         ~> adm_not_below
   915   adm_compact_not_less ~> adm_compact_not_below
   916   less_fun_def         ~> below_fun_def
   917   expand_fun_less      ~> fun_below_iff
   918   less_fun_ext         ~> fun_belowI
   919   less_discr_def       ~> below_discr_def
   920   discr_less_eq        ~> discr_below_eq
   921   less_unit_def        ~> below_unit_def
   922   less_cprod_def       ~> below_prod_def
   923   prod_lessI           ~> prod_belowI
   924   Pair_less_iff        ~> Pair_below_iff
   925   fst_less_iff         ~> fst_below_iff
   926   snd_less_iff         ~> snd_below_iff
   927   expand_cfun_less     ~> cfun_below_iff
   928   less_cfun_ext        ~> cfun_belowI
   929   injection_less       ~> injection_below
   930   less_up_def          ~> below_up_def
   931   not_Iup_less         ~> not_Iup_below
   932   Iup_less             ~> Iup_below
   933   up_less              ~> up_below
   934   Def_inject_less_eq   ~> Def_below_Def
   935   Def_less_is_eq       ~> Def_below_iff
   936   spair_less_iff       ~> spair_below_iff
   937   less_sprod           ~> below_sprod
   938   spair_less           ~> spair_below
   939   sfst_less_iff        ~> sfst_below_iff
   940   ssnd_less_iff        ~> ssnd_below_iff
   941   fix_least_less       ~> fix_least_below
   942   dist_less_one        ~> dist_below_one
   943   less_ONE             ~> below_ONE
   944   ONE_less_iff         ~> ONE_below_iff
   945   less_sinlD           ~> below_sinlD
   946   less_sinrD           ~> below_sinrD
   947 
   948 
   949 *** FOL and ZF ***
   950 
   951 * All constant names are now qualified internally and use proper
   952 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
   953 
   954 
   955 *** ML ***
   956 
   957 * Antiquotation @{assert} inlines a function bool -> unit that raises
   958 Fail if the argument is false.  Due to inlining the source position of
   959 failed assertions is included in the error output.
   960 
   961 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
   962 text is in practice always evaluated with a stable theory checkpoint.
   963 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
   964 
   965 * Antiquotation @{theory A} refers to theory A from the ancestry of
   966 the current context, not any accidental theory loader state as before.
   967 Potential INCOMPATIBILITY, subtle change in semantics.
   968 
   969 * Syntax.pretty_priority (default 0) configures the required priority
   970 of pretty-printed output and thus affects insertion of parentheses.
   971 
   972 * Syntax.default_root (default "any") configures the inner syntax
   973 category (nonterminal symbol) for parsing of terms.
   974 
   975 * Former exception Library.UnequalLengths now coincides with
   976 ListPair.UnequalLengths.
   977 
   978 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
   979 main functionality is provided by structure Simplifier.
   980 
   981 * Renamed raw "explode" function to "raw_explode" to emphasize its
   982 meaning.  Note that internally to Isabelle, Symbol.explode is used in
   983 almost all situations.
   984 
   985 * Discontinued obsolete function sys_error and exception SYS_ERROR.
   986 See implementation manual for further details on exceptions in
   987 Isabelle/ML.
   988 
   989 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
   990 meaning.
   991 
   992 * Renamed structure PureThy to Pure_Thy and moved most of its
   993 operations to structure Global_Theory, to emphasize that this is
   994 rarely-used global-only stuff.
   995 
   996 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
   997 instead (or tracing for high-volume output).
   998 
   999 * Configuration option show_question_marks only affects regular pretty
  1000 printing of types and terms, not raw Term.string_of_vname.
  1001 
  1002 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
  1003 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
  1004 @{thms} for most purposes.
  1005 
  1006 * ML structure Unsynchronized is never opened, not even in Isar
  1007 interaction mode as before.  Old Unsynchronized.set etc. have been
  1008 discontinued -- use plain := instead.  This should be *rare* anyway,
  1009 since modern tools always work via official context data, notably
  1010 configuration options.
  1011 
  1012 * Parallel and asynchronous execution requires special care concerning
  1013 interrupts.  Structure Exn provides some convenience functions that
  1014 avoid working directly with raw Interrupt.  User code must not absorb
  1015 interrupts -- intermediate handling (for cleanup etc.) needs to be
  1016 followed by re-raising of the original exception.  Another common
  1017 source of mistakes are "handle _" patterns, which make the meaning of
  1018 the program subject to physical effects of the environment.
  1019 
  1020 
  1021 
  1022 New in Isabelle2009-2 (June 2010)
  1023 ---------------------------------
  1024 
  1025 *** General ***
  1026 
  1027 * Authentic syntax for *all* logical entities (type classes, type
  1028 constructors, term constants): provides simple and robust
  1029 correspondence between formal entities and concrete syntax.  Within
  1030 the parse tree / AST representations, "constants" are decorated by
  1031 their category (class, type, const) and spelled out explicitly with
  1032 their full internal name.
  1033 
  1034 Substantial INCOMPATIBILITY concerning low-level syntax declarations
  1035 and translations (translation rules and translation functions in ML).
  1036 Some hints on upgrading:
  1037 
  1038   - Many existing uses of 'syntax' and 'translations' can be replaced
  1039     by more modern 'type_notation', 'notation' and 'abbreviation',
  1040     which are independent of this issue.
  1041 
  1042   - 'translations' require markup within the AST; the term syntax
  1043     provides the following special forms:
  1044 
  1045       CONST c   -- produces syntax version of constant c from context
  1046       XCONST c  -- literally c, checked as constant from context
  1047       c         -- literally c, if declared by 'syntax'
  1048 
  1049     Plain identifiers are treated as AST variables -- occasionally the
  1050     system indicates accidental variables via the error "rhs contains
  1051     extra variables".
  1052 
  1053     Type classes and type constructors are marked according to their
  1054     concrete syntax.  Some old translations rules need to be written
  1055     for the "type" category, using type constructor application
  1056     instead of pseudo-term application of the default category
  1057     "logic".
  1058 
  1059   - 'parse_translation' etc. in ML may use the following
  1060     antiquotations:
  1061 
  1062       @{class_syntax c}   -- type class c within parse tree / AST
  1063       @{term_syntax c}    -- type constructor c within parse tree / AST
  1064       @{const_syntax c}   -- ML version of "CONST c" above
  1065       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
  1066 
  1067   - Literal types within 'typed_print_translations', i.e. those *not*
  1068     represented as pseudo-terms are represented verbatim.  Use @{class
  1069     c} or @{type_name c} here instead of the above syntax
  1070     antiquotations.
  1071 
  1072 Note that old non-authentic syntax was based on unqualified base
  1073 names, so all of the above "constant" names would coincide.  Recall
  1074 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
  1075 diagnose syntax problems.
  1076 
  1077 * Type constructors admit general mixfix syntax, not just infix.
  1078 
  1079 * Concrete syntax may be attached to local entities without a proof
  1080 body, too.  This works via regular mixfix annotations for 'fix',
  1081 'def', 'obtain' etc. or via the explicit 'write' command, which is
  1082 similar to the 'notation' command in theory specifications.
  1083 
  1084 * Discontinued unnamed infix syntax (legacy feature for many years) --
  1085 need to specify constant name and syntax separately.  Internal ML
  1086 datatype constructors have been renamed from InfixName to Infix etc.
  1087 Minor INCOMPATIBILITY.
  1088 
  1089 * Schematic theorem statements need to be explicitly markup as such,
  1090 via commands 'schematic_lemma', 'schematic_theorem',
  1091 'schematic_corollary'.  Thus the relevance of the proof is made
  1092 syntactically clear, which impacts performance in a parallel or
  1093 asynchronous interactive environment.  Minor INCOMPATIBILITY.
  1094 
  1095 * Use of cumulative prems via "!" in some proof methods has been
  1096 discontinued (old legacy feature).
  1097 
  1098 * References 'trace_simp' and 'debug_simp' have been replaced by
  1099 configuration options stored in the context. Enabling tracing (the
  1100 case of debugging is similar) in proofs works via
  1101 
  1102   using [[trace_simp = true]]
  1103 
  1104 Tracing is then active for all invocations of the simplifier in
  1105 subsequent goal refinement steps. Tracing may also still be enabled or
  1106 disabled via the ProofGeneral settings menu.
  1107 
  1108 * Separate commands 'hide_class', 'hide_type', 'hide_const',
  1109 'hide_fact' replace the former 'hide' KIND command.  Minor
  1110 INCOMPATIBILITY.
  1111 
  1112 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
  1113 more efficient than combinations with -q1 or -q2.
  1114 
  1115 
  1116 *** Pure ***
  1117 
  1118 * Proofterms record type-class reasoning explicitly, using the
  1119 "unconstrain" operation internally.  This eliminates all sort
  1120 constraints from a theorem and proof, introducing explicit
  1121 OFCLASS-premises.  On the proof term level, this operation is
  1122 automatically applied at theorem boundaries, such that closed proofs
  1123 are always free of sort constraints.  INCOMPATIBILITY for tools that
  1124 inspect proof terms.
  1125 
  1126 * Local theory specifications may depend on extra type variables that
  1127 are not present in the result type -- arguments TYPE('a) :: 'a itself
  1128 are added internally.  For example:
  1129 
  1130   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
  1131 
  1132 * Predicates of locales introduced by classes carry a mandatory
  1133 "class" prefix.  INCOMPATIBILITY.
  1134 
  1135 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
  1136 
  1137 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
  1138 'class' instead.
  1139 
  1140 * Command 'code_reflect' allows to incorporate generated ML code into
  1141 runtime environment; replaces immature code_datatype antiquotation.
  1142 INCOMPATIBILITY.
  1143 
  1144 * Code generator: simple concept for abstract datatypes obeying
  1145 invariants.
  1146 
  1147 * Code generator: details of internal data cache have no impact on the
  1148 user space functionality any longer.
  1149 
  1150 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  1151 subgoals.  This is more appropriate for interpretations with 'where'.
  1152 INCOMPATIBILITY.
  1153 
  1154 * Command 'example_proof' opens an empty proof body.  This allows to
  1155 experiment with Isar, without producing any persistent result.
  1156 
  1157 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  1158 within a local theory context, with explicit checking of the
  1159 constructors involved (in contrast to the raw 'syntax' versions).
  1160 
  1161 * Commands 'types' and 'typedecl' now work within a local theory
  1162 context -- without introducing dependencies on parameters or
  1163 assumptions, which is not possible in Isabelle/Pure.
  1164 
  1165 * Command 'defaultsort' has been renamed to 'default_sort', it works
  1166 within a local theory context.  Minor INCOMPATIBILITY.
  1167 
  1168 
  1169 *** HOL ***
  1170 
  1171 * Command 'typedef' now works within a local theory context -- without
  1172 introducing dependencies on parameters or assumptions, which is not
  1173 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  1174 contain multiple interpretations of local typedefs (with different
  1175 non-emptiness proofs), even in a global theory context.
  1176 
  1177 * New package for quotient types.  Commands 'quotient_type' and
  1178 'quotient_definition' may be used for defining types and constants by
  1179 quotient constructions.  An example is the type of integers created by
  1180 quotienting pairs of natural numbers:
  1181 
  1182   fun
  1183     intrel :: "(nat * nat) => (nat * nat) => bool"
  1184   where
  1185     "intrel (x, y) (u, v) = (x + v = u + y)"
  1186 
  1187   quotient_type int = "nat * nat" / intrel
  1188     by (auto simp add: equivp_def expand_fun_eq)
  1189 
  1190   quotient_definition
  1191     "0::int" is "(0::nat, 0::nat)"
  1192 
  1193 The method "lifting" can be used to lift of theorems from the
  1194 underlying "raw" type to the quotient type.  The example
  1195 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  1196 construction and provides a reasoning infrastructure for finite sets.
  1197 
  1198 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  1199 clash with new theory Quotient in Main HOL.
  1200 
  1201 * Moved the SMT binding into the main HOL session, eliminating
  1202 separate HOL-SMT session.
  1203 
  1204 * List membership infix mem operation is only an input abbreviation.
  1205 INCOMPATIBILITY.
  1206 
  1207 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  1208 for future developements; former Library/Word.thy is still present in
  1209 the AFP entry RSAPPS.
  1210 
  1211 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  1212 longer shadowed.  INCOMPATIBILITY.
  1213 
  1214 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  1215 INCOMPATIBILITY.
  1216 
  1217 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  1218 INCOMPATIBILITY.
  1219 
  1220 * Dropped normalizing_semiring etc; use the facts in semiring classes
  1221 instead.  INCOMPATIBILITY.
  1222 
  1223 * Dropped several real-specific versions of lemmas about floor and
  1224 ceiling; use the generic lemmas from theory "Archimedean_Field"
  1225 instead.  INCOMPATIBILITY.
  1226 
  1227   floor_number_of_eq         ~> floor_number_of
  1228   le_floor_eq_number_of      ~> number_of_le_floor
  1229   le_floor_eq_zero           ~> zero_le_floor
  1230   le_floor_eq_one            ~> one_le_floor
  1231   floor_less_eq_number_of    ~> floor_less_number_of
  1232   floor_less_eq_zero         ~> floor_less_zero
  1233   floor_less_eq_one          ~> floor_less_one
  1234   less_floor_eq_number_of    ~> number_of_less_floor
  1235   less_floor_eq_zero         ~> zero_less_floor
  1236   less_floor_eq_one          ~> one_less_floor
  1237   floor_le_eq_number_of      ~> floor_le_number_of
  1238   floor_le_eq_zero           ~> floor_le_zero
  1239   floor_le_eq_one            ~> floor_le_one
  1240   floor_subtract_number_of   ~> floor_diff_number_of
  1241   floor_subtract_one         ~> floor_diff_one
  1242   ceiling_number_of_eq       ~> ceiling_number_of
  1243   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  1244   ceiling_le_zero_eq         ~> ceiling_le_zero
  1245   ceiling_le_eq_one          ~> ceiling_le_one
  1246   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  1247   less_ceiling_eq_zero       ~> zero_less_ceiling
  1248   less_ceiling_eq_one        ~> one_less_ceiling
  1249   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  1250   ceiling_less_eq_zero       ~> ceiling_less_zero
  1251   ceiling_less_eq_one        ~> ceiling_less_one
  1252   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  1253   le_ceiling_eq_zero         ~> zero_le_ceiling
  1254   le_ceiling_eq_one          ~> one_le_ceiling
  1255   ceiling_subtract_number_of ~> ceiling_diff_number_of
  1256   ceiling_subtract_one       ~> ceiling_diff_one
  1257 
  1258 * Theory "Finite_Set": various folding_XXX locales facilitate the
  1259 application of the various fold combinators on finite sets.
  1260 
  1261 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  1262 provides abstract red-black tree type which is backed by "RBT_Impl" as
  1263 implementation.  INCOMPATIBILTY.
  1264 
  1265 * Theory Library/Coinductive_List has been removed -- superseded by
  1266 AFP/thys/Coinductive.
  1267 
  1268 * Theory PReal, including the type "preal" and related operations, has
  1269 been removed.  INCOMPATIBILITY.
  1270 
  1271 * Real: new development using Cauchy Sequences.
  1272 
  1273 * Split off theory "Big_Operators" containing setsum, setprod,
  1274 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  1275 
  1276 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  1277 "Int" etc.  INCOMPATIBILITY.
  1278 
  1279 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  1280 
  1281 * New set of rules "ac_simps" provides combined assoc / commute
  1282 rewrites for all interpretations of the appropriate generic locales.
  1283 
  1284 * Renamed theory "OrderedGroup" to "Groups" and split theory
  1285 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  1286 appropriate and more consistent names suitable for name prefixes
  1287 within the HOL theories.  INCOMPATIBILITY.
  1288 
  1289 * Some generic constants have been put to appropriate theories:
  1290   - less_eq, less: Orderings
  1291   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  1292   - inverse, divide: Rings
  1293 INCOMPATIBILITY.
  1294 
  1295 * More consistent naming of type classes involving orderings (and
  1296 lattices):
  1297 
  1298     lower_semilattice                   ~> semilattice_inf
  1299     upper_semilattice                   ~> semilattice_sup
  1300 
  1301     dense_linear_order                  ~> dense_linorder
  1302 
  1303     pordered_ab_group_add               ~> ordered_ab_group_add
  1304     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  1305     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  1306     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  1307     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  1308     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  1309     pordered_cancel_semiring            ~> ordered_cancel_semiring
  1310     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  1311     pordered_comm_ring                  ~> ordered_comm_ring
  1312     pordered_comm_semiring              ~> ordered_comm_semiring
  1313     pordered_ring                       ~> ordered_ring
  1314     pordered_ring_abs                   ~> ordered_ring_abs
  1315     pordered_semiring                   ~> ordered_semiring
  1316 
  1317     ordered_ab_group_add                ~> linordered_ab_group_add
  1318     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  1319     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  1320     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  1321     ordered_field                       ~> linordered_field
  1322     ordered_field_no_lb                 ~> linordered_field_no_lb
  1323     ordered_field_no_ub                 ~> linordered_field_no_ub
  1324     ordered_field_dense_linear_order    ~> dense_linordered_field
  1325     ordered_idom                        ~> linordered_idom
  1326     ordered_ring                        ~> linordered_ring
  1327     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  1328     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  1329     ordered_ring_strict                 ~> linordered_ring_strict
  1330     ordered_semidom                     ~> linordered_semidom
  1331     ordered_semiring                    ~> linordered_semiring
  1332     ordered_semiring_1                  ~> linordered_semiring_1
  1333     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  1334     ordered_semiring_strict             ~> linordered_semiring_strict
  1335 
  1336   The following slightly odd type classes have been moved to a
  1337   separate theory Library/Lattice_Algebras:
  1338 
  1339     lordered_ab_group_add               ~> lattice_ab_group_add
  1340     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  1341     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  1342     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  1343     lordered_ring                       ~> lattice_ring
  1344 
  1345 INCOMPATIBILITY.
  1346 
  1347 * Refined field classes:
  1348   - classes division_ring_inverse_zero, field_inverse_zero,
  1349     linordered_field_inverse_zero include rule inverse 0 = 0 --
  1350     subsumes former division_by_zero class;
  1351   - numerous lemmas have been ported from field to division_ring.
  1352 INCOMPATIBILITY.
  1353 
  1354 * Refined algebra theorem collections:
  1355   - dropped theorem group group_simps, use algebra_simps instead;
  1356   - dropped theorem group ring_simps, use field_simps instead;
  1357   - proper theorem collection field_simps subsumes former theorem
  1358     groups field_eq_simps and field_simps;
  1359   - dropped lemma eq_minus_self_iff which is a duplicate for
  1360     equal_neg_zero.
  1361 INCOMPATIBILITY.
  1362 
  1363 * Theory Finite_Set and List: some lemmas have been generalized from
  1364 sets to lattices:
  1365 
  1366   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  1367   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  1368   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  1369   union_Union_fold_union        ~> sup_Sup_fold_sup
  1370   Inter_fold_inter              ~> Inf_fold_inf
  1371   Union_fold_union              ~> Sup_fold_sup
  1372   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  1373   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  1374   INTER_fold_inter              ~> INFI_fold_inf
  1375   UNION_fold_union              ~> SUPR_fold_sup
  1376 
  1377 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  1378 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  1379 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  1380 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  1381 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  1382 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  1383 
  1384 * Reorganized theory Multiset: swapped notation of pointwise and
  1385 multiset order:
  1386 
  1387   - pointwise ordering is instance of class order with standard syntax
  1388     <= and <;
  1389   - multiset ordering has syntax <=# and <#; partial order properties
  1390     are provided by means of interpretation with prefix
  1391     multiset_order;
  1392   - less duplication, less historical organization of sections,
  1393     conversion from associations lists to multisets, rudimentary code
  1394     generation;
  1395   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  1396     if needed.
  1397 
  1398 Renamed:
  1399 
  1400   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  1401   multi_count_ext  ~>  multiset_ext
  1402   diff_union_inverse2  ~>  diff_union_cancelR
  1403 
  1404 INCOMPATIBILITY.
  1405 
  1406 * Theory Permutation: replaced local "remove" by List.remove1.
  1407 
  1408 * Code generation: ML and OCaml code is decorated with signatures.
  1409 
  1410 * Theory List: added transpose.
  1411 
  1412 * Library/Nat_Bijection.thy is a collection of bijective functions
  1413 between nat and other types, which supersedes the older libraries
  1414 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  1415 
  1416   Constants:
  1417   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  1418   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  1419   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  1420   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  1421   Countable.pair_encode           ~> prod_encode
  1422   NatIso.prod2nat                 ~> prod_encode
  1423   NatIso.nat2prod                 ~> prod_decode
  1424   NatIso.sum2nat                  ~> sum_encode
  1425   NatIso.nat2sum                  ~> sum_decode
  1426   NatIso.list2nat                 ~> list_encode
  1427   NatIso.nat2list                 ~> list_decode
  1428   NatIso.set2nat                  ~> set_encode
  1429   NatIso.nat2set                  ~> set_decode
  1430 
  1431   Lemmas:
  1432   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  1433   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  1434   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  1435   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  1436   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  1437   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  1438   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  1439   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  1440   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  1441   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  1442   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  1443   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  1444   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  1445 
  1446 * Sledgehammer:
  1447   - Renamed ATP commands:
  1448     atp_info     ~> sledgehammer running_atps
  1449     atp_kill     ~> sledgehammer kill_atps
  1450     atp_messages ~> sledgehammer messages
  1451     atp_minimize ~> sledgehammer minimize
  1452     print_atps   ~> sledgehammer available_atps
  1453     INCOMPATIBILITY.
  1454   - Added user's manual ("isabelle doc sledgehammer").
  1455   - Added option syntax and "sledgehammer_params" to customize
  1456     Sledgehammer's behavior.  See the manual for details.
  1457   - Modified the Isar proof reconstruction code so that it produces
  1458     direct proofs rather than proofs by contradiction.  (This feature
  1459     is still experimental.)
  1460   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  1461     full-typed mode.
  1462   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  1463 
  1464 * Nitpick:
  1465   - Added and implemented "binary_ints" and "bits" options.
  1466   - Added "std" option and implemented support for nonstandard models.
  1467   - Added and implemented "finitize" option to improve the precision
  1468     of infinite datatypes based on a monotonicity analysis.
  1469   - Added support for quotient types.
  1470   - Added support for "specification" and "ax_specification"
  1471     constructs.
  1472   - Added support for local definitions (for "function" and
  1473     "termination" proofs).
  1474   - Added support for term postprocessors.
  1475   - Optimized "Multiset.multiset" and "FinFun.finfun".
  1476   - Improved efficiency of "destroy_constrs" optimization.
  1477   - Fixed soundness bugs related to "destroy_constrs" optimization and
  1478     record getters.
  1479   - Fixed soundness bug related to higher-order constructors.
  1480   - Fixed soundness bug when "full_descrs" is enabled.
  1481   - Improved precision of set constructs.
  1482   - Added "atoms" option.
  1483   - Added cache to speed up repeated Kodkod invocations on the same
  1484     problems.
  1485   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  1486     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  1487     "SAT4J_Light".  INCOMPATIBILITY.
  1488   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  1489     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  1490   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  1491 
  1492 * Method "induct" now takes instantiations of the form t, where t is not
  1493   a variable, as a shorthand for "x == t", where x is a fresh variable.
  1494   If this is not intended, t has to be enclosed in parentheses.
  1495   By default, the equalities generated by definitional instantiations
  1496   are pre-simplified, which may cause parameters of inductive cases
  1497   to disappear, or may even delete some of the inductive cases.
  1498   Use "induct (no_simp)" instead of "induct" to restore the old
  1499   behaviour. The (no_simp) option is also understood by the "cases"
  1500   and "nominal_induct" methods, which now perform pre-simplification, too.
  1501   INCOMPATIBILITY.
  1502 
  1503 
  1504 *** HOLCF ***
  1505 
  1506 * Variable names in lemmas generated by the domain package have
  1507 changed; the naming scheme is now consistent with the HOL datatype
  1508 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  1509 
  1510 * The domain package no longer defines the function "foo_copy" for
  1511 recursive domain "foo".  The reach lemma is now stated directly in
  1512 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  1513 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  1514 
  1515 * Most definedness lemmas generated by the domain package (previously
  1516 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  1517 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  1518 Proofs that used definedness lemmas as intro rules may break,
  1519 potential INCOMPATIBILITY.
  1520 
  1521 * Induction and casedist rules generated by the domain package now
  1522 declare proper case_names (one called "bottom", and one named for each
  1523 constructor).  INCOMPATIBILITY.
  1524 
  1525 * For mutually-recursive domains, separate "reach" and "take_lemma"
  1526 rules are generated for each domain, INCOMPATIBILITY.
  1527 
  1528   foo_bar.reach       ~> foo.reach  bar.reach
  1529   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  1530 
  1531 * Some lemmas generated by the domain package have been renamed for
  1532 consistency with the datatype package, INCOMPATIBILITY.
  1533 
  1534   foo.ind        ~> foo.induct
  1535   foo.finite_ind ~> foo.finite_induct
  1536   foo.coind      ~> foo.coinduct
  1537   foo.casedist   ~> foo.exhaust
  1538   foo.exhaust    ~> foo.nchotomy
  1539 
  1540 * For consistency with other definition packages, the fixrec package
  1541 now generates qualified theorem names, INCOMPATIBILITY.
  1542 
  1543   foo_simps  ~> foo.simps
  1544   foo_unfold ~> foo.unfold
  1545   foo_induct ~> foo.induct
  1546 
  1547 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  1548 method and internal fixrec proofs now use the default simpset instead.
  1549 INCOMPATIBILITY.
  1550 
  1551 * The "contlub" predicate has been removed.  Proof scripts should use
  1552 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  1553 
  1554 * The "admw" predicate has been removed, INCOMPATIBILITY.
  1555 
  1556 * The constants cpair, cfst, and csnd have been removed in favor of
  1557 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  1558 
  1559 
  1560 *** ML ***
  1561 
  1562 * Antiquotations for basic formal entities:
  1563 
  1564     @{class NAME}         -- type class
  1565     @{class_syntax NAME}  -- syntax representation of the above
  1566 
  1567     @{type_name NAME}     -- logical type
  1568     @{type_abbrev NAME}   -- type abbreviation
  1569     @{nonterminal NAME}   -- type of concrete syntactic category
  1570     @{type_syntax NAME}   -- syntax representation of any of the above
  1571 
  1572     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  1573     @{const_abbrev NAME}  -- abbreviated constant
  1574     @{const_syntax NAME}  -- syntax representation of any of the above
  1575 
  1576 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  1577 syntax constant (cf. 'syntax' command).
  1578 
  1579 * Antiquotation @{make_string} inlines a function to print arbitrary
  1580 values similar to the ML toplevel.  The result is compiler dependent
  1581 and may fall back on "?" in certain situations.
  1582 
  1583 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  1584 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  1585 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  1586 not work with the asynchronous Isar document model.
  1587 
  1588 * Configuration options now admit dynamic default values, depending on
  1589 the context or even global references.
  1590 
  1591 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  1592 uses an efficient external library if available (for Poly/ML).
  1593 
  1594 * Renamed some important ML structures, while keeping the old names
  1595 for some time as aliases within the structure Legacy:
  1596 
  1597   OuterKeyword  ~>  Keyword
  1598   OuterLex      ~>  Token
  1599   OuterParse    ~>  Parse
  1600   OuterSyntax   ~>  Outer_Syntax
  1601   PrintMode     ~>  Print_Mode
  1602   SpecParse     ~>  Parse_Spec
  1603   ThyInfo       ~>  Thy_Info
  1604   ThyLoad       ~>  Thy_Load
  1605   ThyOutput     ~>  Thy_Output
  1606   TypeInfer     ~>  Type_Infer
  1607 
  1608 Note that "open Legacy" simplifies porting of sources, but forgetting
  1609 to remove it again will complicate porting again in the future.
  1610 
  1611 * Most operations that refer to a global context are named
  1612 accordingly, e.g. Simplifier.global_context or
  1613 ProofContext.init_global.  There are some situations where a global
  1614 context actually works, but under normal circumstances one needs to
  1615 pass the proper local context through the code!
  1616 
  1617 * Discontinued old TheoryDataFun with its copy/init operation -- data
  1618 needs to be pure.  Functor Theory_Data_PP retains the traditional
  1619 Pretty.pp argument to merge, which is absent in the standard
  1620 Theory_Data version.
  1621 
  1622 * Sorts.certify_sort and derived "cert" operations for types and terms
  1623 no longer minimize sorts.  Thus certification at the boundary of the
  1624 inference kernel becomes invariant under addition of class relations,
  1625 which is an important monotonicity principle.  Sorts are now minimized
  1626 in the syntax layer only, at the boundary between the end-user and the
  1627 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  1628 explicitly in rare situations.
  1629 
  1630 * Renamed old-style Drule.standard to Drule.export_without_context, to
  1631 emphasize that this is in no way a standard operation.
  1632 INCOMPATIBILITY.
  1633 
  1634 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  1635 usual for resolution.  Rare INCOMPATIBILITY.
  1636 
  1637 * Renamed varify/unvarify operations to varify_global/unvarify_global
  1638 to emphasize that these only work in a global situation (which is
  1639 quite rare).
  1640 
  1641 * Curried take and drop in library.ML; negative length is interpreted
  1642 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  1643 
  1644 * Proof terms: type substitutions on proof constants now use canonical
  1645 order of type variables.  INCOMPATIBILITY for tools working with proof
  1646 terms.
  1647 
  1648 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  1649 may no longer carry premises.  User-level specifications are
  1650 transformed accordingly by Thm.add_axiom/add_def.
  1651 
  1652 
  1653 *** System ***
  1654 
  1655 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  1656 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  1657 proof terms are enabled unconditionally in the new HOL-Proofs image.
  1658 
  1659 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  1660 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  1661 respectively.
  1662 
  1663 * Old lib/scripts/polyml-platform is superseded by the
  1664 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  1665 variant, even on a 64 bit machine.  The following example setting
  1666 prefers 64 bit if available:
  1667 
  1668   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  1669 
  1670 * The preliminary Isabelle/jEdit application demonstrates the emerging
  1671 Isabelle/Scala layer for advanced prover interaction and integration.
  1672 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  1673 component.
  1674 
  1675 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  1676 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  1677 similar to the default assignment of the document preparation system
  1678 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  1679 provides some operations for direct access to the font without asking
  1680 the user for manual installation.
  1681 
  1682 
  1683 
  1684 New in Isabelle2009-1 (December 2009)
  1685 -------------------------------------
  1686 
  1687 *** General ***
  1688 
  1689 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  1690 one backslash should be used, even in ML sources.
  1691 
  1692 
  1693 *** Pure ***
  1694 
  1695 * Locale interpretation propagates mixins along the locale hierarchy.
  1696 The currently only available mixins are the equations used to map
  1697 local definitions to terms of the target domain of an interpretation.
  1698 
  1699 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  1700 loc" to print all interpretations of locale "loc" in the theory.
  1701 Interpretations in proofs are not shown.
  1702 
  1703 * Thoroughly revised locales tutorial.  New section on conditional
  1704 interpretation.
  1705 
  1706 * On instantiation of classes, remaining undefined class parameters
  1707 are formally declared.  INCOMPATIBILITY.
  1708 
  1709 
  1710 *** Document preparation ***
  1711 
  1712 * New generalized style concept for printing terms: @{foo (style) ...}
  1713 instead of @{foo_style style ...}  (old form is still retained for
  1714 backward compatibility).  Styles can be also applied for
  1715 antiquotations prop, term_type and typeof.
  1716 
  1717 
  1718 *** HOL ***
  1719 
  1720 * New proof method "smt" for a combination of first-order logic with
  1721 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  1722 fixed-size bitvectors; there is also basic support for higher-order
  1723 features (esp. lambda abstractions).  It is an incomplete decision
  1724 procedure based on external SMT solvers using the oracle mechanism;
  1725 for the SMT solver Z3, this method is proof-producing.  Certificates
  1726 are provided to avoid calling the external solvers solely for
  1727 re-checking proofs.  Due to a remote SMT service there is no need for
  1728 installing SMT solvers locally.  See src/HOL/SMT.
  1729 
  1730 * New commands to load and prove verification conditions generated by
  1731 the Boogie program verifier or derived systems (e.g. the Verifying C
  1732 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1733 
  1734 * New counterexample generator tool 'nitpick' based on the Kodkod
  1735 relational model finder.  See src/HOL/Tools/Nitpick and
  1736 src/HOL/Nitpick_Examples.
  1737 
  1738 * New commands 'code_pred' and 'values' to invoke the predicate
  1739 compiler and to enumerate values of inductive predicates.
  1740 
  1741 * A tabled implementation of the reflexive transitive closure.
  1742 
  1743 * New implementation of quickcheck uses generic code generator;
  1744 default generators are provided for all suitable HOL types, records
  1745 and datatypes.  Old quickcheck can be re-activated importing theory
  1746 Library/SML_Quickcheck.
  1747 
  1748 * New testing tool Mirabelle for automated proof tools.  Applies
  1749 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1750 every proof step in a theory.  To be used in batch mode via the
  1751 "mirabelle" utility.
  1752 
  1753 * New proof method "sos" (sum of squares) for nonlinear real
  1754 arithmetic (originally due to John Harison). It requires theory
  1755 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1756 works well in practice on quantifier-free real arithmetic with +, -,
  1757 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1758 inequalities between polynomials.  It makes use of external
  1759 semidefinite programming solvers.  Method "sos" generates a
  1760 certificate that can be pasted into the proof thus avoiding the need
  1761 to call an external tool every time the proof is checked.  See
  1762 src/HOL/Library/Sum_Of_Squares.
  1763 
  1764 * New method "linarith" invokes existing linear arithmetic decision
  1765 procedure only.
  1766 
  1767 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1768 
  1769 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1770 Causes full type information to be output to the ATPs.  This slows
  1771 ATPs down considerably but eliminates a source of unsound "proofs"
  1772 that fail later.
  1773 
  1774 * New method "metisFT": A version of metis that uses full type
  1775 information in order to avoid failures of proof reconstruction.
  1776 
  1777 * New evaluator "approximate" approximates an real valued term using
  1778 the same method as the approximation method.
  1779 
  1780 * Method "approximate" now supports arithmetic expressions as
  1781 boundaries of intervals and implements interval splitting and Taylor
  1782 series expansion.
  1783 
  1784 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1785 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1786 
  1787 * New theory SupInf of the supremum and infimum operators for sets of
  1788 reals.
  1789 
  1790 * New theory Probability, which contains a development of measure
  1791 theory, eventually leading to Lebesgue integration and probability.
  1792 
  1793 * Extended Multivariate Analysis to include derivation and Brouwer's
  1794 fixpoint theorem.
  1795 
  1796 * Reorganization of number theory, INCOMPATIBILITY:
  1797   - new number theory development for nat and int, in theories Divides
  1798     and GCD as well as in new session Number_Theory
  1799   - some constants and facts now suffixed with _nat and _int
  1800     accordingly
  1801   - former session NumberTheory now named Old_Number_Theory, including
  1802     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1803   - moved theory Pocklington from src/HOL/Library to
  1804     src/HOL/Old_Number_Theory
  1805 
  1806 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1807 lcm of finite and infinite sets. It is shown that they form a complete
  1808 lattice.
  1809 
  1810 * Class semiring_div requires superclass no_zero_divisors and proof of
  1811 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1812 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1813 generalized to class semiring_div, subsuming former theorems
  1814 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1815 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1816 INCOMPATIBILITY.
  1817 
  1818 * Refinements to lattice classes and sets:
  1819   - less default intro/elim rules in locale variant, more default
  1820     intro/elim rules in class variant: more uniformity
  1821   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1822     le_inf_iff
  1823   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1824     sup_aci)
  1825   - renamed ACI to inf_sup_aci
  1826   - new class "boolean_algebra"
  1827   - class "complete_lattice" moved to separate theory
  1828     "Complete_Lattice"; corresponding constants (and abbreviations)
  1829     renamed and with authentic syntax:
  1830     Set.Inf ~>    Complete_Lattice.Inf
  1831     Set.Sup ~>    Complete_Lattice.Sup
  1832     Set.INFI ~>   Complete_Lattice.INFI
  1833     Set.SUPR ~>   Complete_Lattice.SUPR
  1834     Set.Inter ~>  Complete_Lattice.Inter
  1835     Set.Union ~>  Complete_Lattice.Union
  1836     Set.INTER ~>  Complete_Lattice.INTER
  1837     Set.UNION ~>  Complete_Lattice.UNION
  1838   - authentic syntax for
  1839     Set.Pow
  1840     Set.image
  1841   - mere abbreviations:
  1842     Set.empty               (for bot)
  1843     Set.UNIV                (for top)
  1844     Set.inter               (for inf, formerly Set.Int)
  1845     Set.union               (for sup, formerly Set.Un)
  1846     Complete_Lattice.Inter  (for Inf)
  1847     Complete_Lattice.Union  (for Sup)
  1848     Complete_Lattice.INTER  (for INFI)
  1849     Complete_Lattice.UNION  (for SUPR)
  1850   - object-logic definitions as far as appropriate
  1851 
  1852 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1853 Un_subset_iff are explicitly deleted as default simp rules; then also
  1854 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1855 deleted to achieve the desired effect.
  1856 
  1857 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1858 rules by default any longer; the same applies to min_max.inf_absorb1
  1859 etc.  INCOMPATIBILITY.
  1860 
  1861 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1862 pred_set_conv by default.  INCOMPATIBILITY.
  1863 
  1864 * Power operations on relations and functions are now one dedicated
  1865 constant "compow" with infix syntax "^^".  Power operation on
  1866 multiplicative monoids retains syntax "^" and is now defined generic
  1867 in class power.  INCOMPATIBILITY.
  1868 
  1869 * Relation composition "R O S" now has a more standard argument order:
  1870 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1871 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1872 break, since the O_assoc rule was not rewritten like this.  Fix using
  1873 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1874 
  1875 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1876 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1877 INCOMPATIBILITY.
  1878 
  1879 * Most rules produced by inductive and datatype package have mandatory
  1880 prefixes.  INCOMPATIBILITY.
  1881 
  1882 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1883 the attribute of the same name.  Each of the theorems in the list
  1884 DERIV_intros assumes composition with an additional function and
  1885 matches a variable to the derivative, which has to be solved by the
  1886 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1887 of most elementary terms.  Former Maclauren.DERIV_tac and
  1888 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1889 INCOMPATIBILITY.
  1890 
  1891 * Code generator attributes follow the usual underscore convention:
  1892     code_unfold     replaces    code unfold
  1893     code_post       replaces    code post
  1894     etc.
  1895   INCOMPATIBILITY.
  1896 
  1897 * Renamed methods:
  1898     sizechange -> size_change
  1899     induct_scheme -> induction_schema
  1900   INCOMPATIBILITY.
  1901 
  1902 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1903 INCOMPATIBILITY, use "undefined" directly.
  1904 
  1905 * Renamed theorems:
  1906     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1907     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1908     Suc_plus1 -> Suc_eq_plus1
  1909     *anti_sym -> *antisym*
  1910     vector_less_eq_def -> vector_le_def
  1911   INCOMPATIBILITY.
  1912 
  1913 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1914 INCOMPATIBILITY.
  1915 
  1916 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1917 INCOMPATIBILITY.
  1918 
  1919 
  1920 *** HOLCF ***
  1921 
  1922 * Theory Representable defines a class "rep" of domains that are
  1923 representable (via an ep-pair) in the universal domain type "udom".
  1924 Instances are provided for all type constructors defined in HOLCF.
  1925 
  1926 * The 'new_domain' command is a purely definitional version of the
  1927 domain package, for representable domains.  Syntax is identical to the
  1928 old domain package.  The 'new_domain' package also supports indirect
  1929 recursion using previously-defined type constructors.  See
  1930 src/HOLCF/ex/New_Domain.thy for examples.
  1931 
  1932 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1933 on the left-hand side of an equation, and then performs
  1934 simplification.  Rewriting is done using rules declared with the
  1935 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1936 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1937 
  1938 * The pattern-match compiler in 'fixrec' can now handle constructors
  1939 with HOL function types.  Pattern-match combinators for the Pair
  1940 constructor are pre-configured.
  1941 
  1942 * The 'fixrec' package now produces better fixed-point induction rules
  1943 for mutually-recursive definitions:  Induction rules have conclusions
  1944 of the form "P foo bar" instead of "P <foo, bar>".
  1945 
  1946 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1947 been renamed to "below".  The name "below" now replaces "less" in many
  1948 theorem names.  (Legacy theorem names using "less" are still supported
  1949 as well.)
  1950 
  1951 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1952 patterns can be used to generate strictness rules, or to make
  1953 functions more strict (much like the bang-patterns supported by the
  1954 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1955 examples.
  1956 
  1957 
  1958 *** ML ***
  1959 
  1960 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1961 errors and run-time exceptions, including detailed source positions.
  1962 
  1963 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1964 identified entries, with some additional information such as source
  1965 position, logical grouping etc.
  1966 
  1967 * Theory and context data is now introduced by the simplified and
  1968 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1969 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1970 copy operation) is still available for some time.
  1971 
  1972 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1973 provides a high-level programming interface to synchronized state
  1974 variables with atomic update.  This works via pure function
  1975 application within a critical section -- its runtime should be as
  1976 short as possible; beware of deadlocks if critical code is nested,
  1977 either directly or indirectly via other synchronized variables!
  1978 
  1979 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1980 wraps raw ML references, explicitly indicating their non-thread-safe
  1981 behaviour.  The Isar toplevel keeps this structure open, to
  1982 accommodate Proof General as well as quick and dirty interactive
  1983 experiments with references.
  1984 
  1985 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1986 parallel tactical reasoning.
  1987 
  1988 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1989 are similar to SUBPROOF, but are slightly more flexible: only the
  1990 specified parts of the subgoal are imported into the context, and the
  1991 body tactic may introduce new subgoals and schematic variables.
  1992 
  1993 * Old tactical METAHYPS, which does not observe the proof context, has
  1994 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1995 or Subgoal.FOCUS etc.
  1996 
  1997 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  1998 functors have their own ML name space there is no point to mark them
  1999 separately.)  Minor INCOMPATIBILITY.
  2000 
  2001 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  2002 
  2003 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  2004 INCOMPATIBILITY.
  2005 
  2006 * Operations of structure Skip_Proof no longer require quick_and_dirty
  2007 mode, which avoids critical setmp.
  2008 
  2009 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  2010 combinators for "args".  INCOMPATIBILITY, need to use simplified
  2011 Attrib/Method.setup introduced in Isabelle2009.
  2012 
  2013 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  2014 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  2015 last resort.  INCOMPATIBILITY.
  2016 
  2017 * Display.pretty_thm now requires a proper context (cf. former
  2018 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  2019 or even Display.pretty_thm_without_context as last resort.
  2020 INCOMPATIBILITY.
  2021 
  2022 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  2023 Syntax.pretty_typ/term directly, preferably with proper context
  2024 instead of global theory.
  2025 
  2026 
  2027 *** System ***
  2028 
  2029 * Further fine tuning of parallel proof checking, scales up to 8 cores
  2030 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  2031 usedir option -q.
  2032 
  2033 * Support for additional "Isabelle components" via etc/components, see
  2034 also the system manual.
  2035 
  2036 * The isabelle makeall tool now operates on all components with
  2037 IsaMakefile, not just hardwired "logics".
  2038 
  2039 * Removed "compress" option from isabelle-process and isabelle usedir;
  2040 this is always enabled.
  2041 
  2042 * Discontinued support for Poly/ML 4.x versions.
  2043 
  2044 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  2045 on a given logic image.  This requires the lighttpd webserver and is
  2046 currently supported on Linux only.
  2047 
  2048 
  2049 
  2050 New in Isabelle2009 (April 2009)
  2051 --------------------------------
  2052 
  2053 *** General ***
  2054 
  2055 * Simplified main Isabelle executables, with less surprises on
  2056 case-insensitive file-systems (such as Mac OS).
  2057 
  2058   - The main Isabelle tool wrapper is now called "isabelle" instead of
  2059     "isatool."
  2060 
  2061   - The former "isabelle" alias for "isabelle-process" has been
  2062     removed (should rarely occur to regular users).
  2063 
  2064   - The former "isabelle-interface" and its alias "Isabelle" have been
  2065     removed (interfaces are now regular Isabelle tools).
  2066 
  2067 Within scripts and make files, the Isabelle environment variables
  2068 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  2069 respectively.  (The latter are still available as legacy feature.)
  2070 
  2071 The old isabelle-interface wrapper could react in confusing ways if
  2072 the interface was uninstalled or changed otherwise.  Individual
  2073 interface tool configuration is now more explicit, see also the
  2074 Isabelle system manual.  In particular, Proof General is now available
  2075 via "isabelle emacs".
  2076 
  2077 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  2078 purge installed copies of Isabelle executables and re-run "isabelle
  2079 install -p ...", or use symlinks.
  2080 
  2081 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  2082 old ~/isabelle, which was slightly non-standard and apt to cause
  2083 surprises on case-insensitive file-systems (such as Mac OS).
  2084 
  2085 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  2086 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  2087 care is required when using older releases of Isabelle.  Note that
  2088 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  2089 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  2090 
  2091 * Proofs of fully specified statements are run in parallel on
  2092 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  2093 a regular 4-core machine, if the initial heap space is made reasonably
  2094 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  2095 
  2096 * The main reference manuals ("isar-ref", "implementation", and
  2097 "system") have been updated and extended.  Formally checked references
  2098 as hyperlinks are now available uniformly.
  2099 
  2100 
  2101 *** Pure ***
  2102 
  2103 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  2104 respects.  The most important changes are listed below.  See the
  2105 Tutorial on Locales ("locales" manual) for details.
  2106 
  2107 - In locale expressions, instantiation replaces renaming.  Parameters
  2108 must be declared in a for clause.  To aid compatibility with previous
  2109 parameter inheritance, in locale declarations, parameters that are not
  2110 'touched' (instantiation position "_" or omitted) are implicitly added
  2111 with their syntax at the beginning of the for clause.
  2112 
  2113 - Syntax from abbreviations and definitions in locales is available in
  2114 locale expressions and context elements.  The latter is particularly
  2115 useful in locale declarations.
  2116 
  2117 - More flexible mechanisms to qualify names generated by locale
  2118 expressions.  Qualifiers (prefixes) may be specified in locale
  2119 expressions, and can be marked as mandatory (syntax: "name!:") or
  2120 optional (syntax "name?:").  The default depends for plain "name:"
  2121 depends on the situation where a locale expression is used: in
  2122 commands 'locale' and 'sublocale' prefixes are optional, in
  2123 'interpretation' and 'interpret' prefixes are mandatory.  The old
  2124 implicit qualifiers derived from the parameter names of a locale are
  2125 no longer generated.
  2126 
  2127 - Command "sublocale l < e" replaces "interpretation l < e".  The
  2128 instantiation clause in "interpretation" and "interpret" (square
  2129 brackets) is no longer available.  Use locale expressions.
  2130 
  2131 - When converting proof scripts, mandatory qualifiers in
  2132 'interpretation' and 'interpret' should be retained by default, even
  2133 if this is an INCOMPATIBILITY compared to former behavior.  In the
  2134 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  2135 in locale expressions range over a single locale instance only.
  2136 
  2137 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  2138 In existing theorem specifications replace the includes element by the
  2139 respective context elements of the included locale, omitting those
  2140 that are already present in the theorem specification.  Multiple
  2141 assume elements of a locale should be replaced by a single one
  2142 involving the locale predicate.  In the proof body, declarations (most
  2143 notably theorems) may be regained by interpreting the respective
  2144 locales in the proof context as required (command "interpret").
  2145 
  2146 If using "includes" in replacement of a target solely because the
  2147 parameter types in the theorem are not as general as in the target,
  2148 consider declaring a new locale with additional type constraints on
  2149 the parameters (context element "constrains").
  2150 
  2151 - Discontinued "locale (open)".  INCOMPATIBILITY.
  2152 
  2153 - Locale interpretation commands no longer attempt to simplify goal.
  2154 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  2155 methods intro_locales and unfold_locales to clarify.
  2156 
  2157 - Locale interpretation commands no longer accept interpretation
  2158 attributes.  INCOMPATIBILITY.
  2159 
  2160 * Class declaration: so-called "base sort" must not be given in import
  2161 list any longer, but is inferred from the specification.  Particularly
  2162 in HOL, write
  2163 
  2164     class foo = ...
  2165 
  2166 instead of
  2167 
  2168     class foo = type + ...
  2169 
  2170 * Class target: global versions of theorems stemming do not carry a
  2171 parameter prefix any longer.  INCOMPATIBILITY.
  2172 
  2173 * Class 'instance' command no longer accepts attached definitions.
  2174 INCOMPATIBILITY, use proper 'instantiation' target instead.
  2175 
  2176 * Recovered hiding of consts, which was accidentally broken in
  2177 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  2178 makes c inaccessible; consider using ``hide (open) const c'' instead.
  2179 
  2180 * Slightly more coherent Pure syntax, with updated documentation in
  2181 isar-ref manual.  Removed locales meta_term_syntax and
  2182 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  2183 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  2184 directly in regular applications.
  2185 
  2186 * There is a new syntactic category "float_const" for signed decimal
  2187 fractions (e.g. 123.45 or -123.45).
  2188 
  2189 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  2190 interface with 'setup' command instead.
  2191 
  2192 * Command 'local_setup' is similar to 'setup', but operates on a local
  2193 theory context.
  2194 
  2195 * The 'axiomatization' command now only works within a global theory
  2196 context.  INCOMPATIBILITY.
  2197 
  2198 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  2199 hypotheses.  Sorts required in the course of reasoning need to be
  2200 covered by the constraints in the initial statement, completed by the
  2201 type instance information of the background theory.  Non-trivial sort
  2202 hypotheses, which rarely occur in practice, may be specified via
  2203 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  2204 
  2205   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  2206 
  2207 The result contains an implicit sort hypotheses as before --
  2208 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  2209 normalization.
  2210 
  2211 * Generalized Isar history, with support for linear undo, direct state
  2212 addressing etc.
  2213 
  2214 * Changed defaults for unify configuration options:
  2215 
  2216   unify_trace_bound = 50 (formerly 25)
  2217   unify_search_bound = 60 (formerly 30)
  2218 
  2219 * Different bookkeeping for code equations (INCOMPATIBILITY):
  2220 
  2221   a) On theory merge, the last set of code equations for a particular
  2222      constant is taken (in accordance with the policy applied by other
  2223      parts of the code generator framework).
  2224 
  2225   b) Code equations stemming from explicit declarations (e.g. code
  2226      attribute) gain priority over default code equations stemming
  2227      from definition, primrec, fun etc.
  2228 
  2229 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  2230 
  2231 * Unified theorem tables for both code generators.  Thus [code
  2232 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  2233 
  2234 * Command 'find_consts' searches for constants based on type and name
  2235 patterns, e.g.
  2236 
  2237     find_consts "_ => bool"
  2238 
  2239 By default, matching is against subtypes, but it may be restricted to
  2240 the whole type.  Searching by name is possible.  Multiple queries are
  2241 conjunctive and queries may be negated by prefixing them with a
  2242 hyphen:
  2243 
  2244     find_consts strict: "_ => bool" name: "Int" -"int => int"
  2245 
  2246 * New 'find_theorems' criterion "solves" matches theorems that
  2247 directly solve the current goal (modulo higher-order unification).
  2248 
  2249 * Auto solve feature for main theorem statements: whenever a new goal
  2250 is stated, "find_theorems solves" is called; any theorems that could
  2251 solve the lemma directly are listed as part of the goal state.
  2252 Cf. associated options in Proof General Isabelle settings menu,
  2253 enabled by default, with reasonable timeout for pathological cases of
  2254 higher-order unification.
  2255 
  2256 
  2257 *** Document preparation ***
  2258 
  2259 * Antiquotation @{lemma} now imitates a regular terminal proof,
  2260 demanding keyword 'by' and supporting the full method expression
  2261 syntax just like the Isar command 'by'.
  2262 
  2263 
  2264 *** HOL ***
  2265 
  2266 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  2267 points Main and Complex_Main remain as before.
  2268 
  2269 * Logic image HOL-Plain provides a minimal HOL with the most important
  2270 tools available (inductive, datatype, primrec, ...).  This facilitates
  2271 experimentation and tool development.  Note that user applications
  2272 (and library theories) should never refer to anything below theory
  2273 Main, as before.
  2274 
  2275 * Logic image HOL-Main stops at theory Main, and thus facilitates
  2276 experimentation due to shorter build times.
  2277 
  2278 * Logic image HOL-NSA contains theories of nonstandard analysis which
  2279 were previously part of former HOL-Complex.  Entry point Hyperreal
  2280 remains valid, but theories formerly using Complex_Main should now use
  2281 new entry point Hypercomplex.
  2282 
  2283 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  2284 Posix processes.  Avoids potentially expensive forking of the ML
  2285 process.  New thread-based implementation also works on non-Unix
  2286 platforms (Cygwin).  Provers are no longer hardwired, but defined
  2287 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  2288 commands are covered in the isar-ref manual.
  2289 
  2290 * Wrapper scripts for remote SystemOnTPTP service allows to use
  2291 sledgehammer without local ATP installation (Vampire etc.). Other
  2292 provers may be included via suitable ML wrappers, see also
  2293 src/HOL/ATP_Linkup.thy.
  2294 
  2295 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  2296 menu.
  2297 
  2298 * The metis method no longer fails because the theorem is too trivial
  2299 (contains the empty clause).
  2300 
  2301 * The metis method now fails in the usual manner, rather than raising
  2302 an exception, if it determines that it cannot prove the theorem.
  2303 
  2304 * Method "coherent" implements a prover for coherent logic (see also
  2305 src/Tools/coherent.ML).
  2306 
  2307 * Constants "undefined" and "default" replace "arbitrary".  Usually
  2308 "undefined" is the right choice to replace "arbitrary", though
  2309 logically there is no difference.  INCOMPATIBILITY.
  2310 
  2311 * Command "value" now integrates different evaluation mechanisms.  The
  2312 result of the first successful evaluation mechanism is printed.  In
  2313 square brackets a particular named evaluation mechanisms may be
  2314 specified (currently, [SML], [code] or [nbe]).  See further
  2315 src/HOL/ex/Eval_Examples.thy.
  2316 
  2317 * Normalization by evaluation now allows non-leftlinear equations.
  2318 Declare with attribute [code nbe].
  2319 
  2320 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  2321 as the structured Isar versions "cases" and "induct", cf. the
  2322 corresponding "cases" and "induct" attributes.  Mutual induction rules
  2323 are now presented as a list of individual projections
  2324 (e.g. foo_bar.inducts for types foo and bar); the old format with
  2325 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  2326 rare situations a different rule is selected --- notably nested tuple
  2327 elimination instead of former prod.exhaust: use explicit (case_tac t
  2328 rule: prod.exhaust) here.
  2329 
  2330 * Attributes "cases", "induct", "coinduct" support "del" option.
  2331 
  2332 * Removed fact "case_split_thm", which duplicates "case_split".
  2333 
  2334 * The option datatype has been moved to a new theory Option.  Renamed
  2335 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  2336 
  2337 * New predicate "strict_mono" classifies strict functions on partial
  2338 orders.  With strict functions on linear orders, reasoning about
  2339 (in)equalities is facilitated by theorems "strict_mono_eq",
  2340 "strict_mono_less_eq" and "strict_mono_less".
  2341 
  2342 * Some set operations are now proper qualified constants with
  2343 authentic syntax.  INCOMPATIBILITY:
  2344 
  2345     op Int ~>   Set.Int
  2346     op Un ~>    Set.Un
  2347     INTER ~>    Set.INTER
  2348     UNION ~>    Set.UNION
  2349     Inter ~>    Set.Inter
  2350     Union ~>    Set.Union
  2351     {} ~>       Set.empty
  2352     UNIV ~>     Set.UNIV
  2353 
  2354 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  2355 theory Set.
  2356 
  2357 * Auxiliary class "itself" has disappeared -- classes without any
  2358 parameter are treated as expected by the 'class' command.
  2359 
  2360 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  2361 
  2362 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  2363 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  2364 
  2365 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  2366 method "approximation".  It proves formulas on real values by using
  2367 interval arithmetic.  In the formulas are also the transcendental
  2368 functions sin, cos, tan, atan, ln, exp and the constant pi are
  2369 allowed. For examples see
  2370 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  2371 
  2372 * Theory "Reflection" now resides in HOL/Library.
  2373 
  2374 * Entry point to Word library now simply named "Word".
  2375 INCOMPATIBILITY.
  2376 
  2377 * Made source layout more coherent with logical distribution
  2378 structure:
  2379 
  2380     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  2381     src/HOL/Library/Code_Message.thy ~> src/HOL/
  2382     src/HOL/Library/GCD.thy ~> src/HOL/
  2383     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  2384     src/HOL/Library/Parity.thy ~> src/HOL/
  2385     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  2386     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  2387     src/HOL/Real/Lubs.thy ~> src/HOL/
  2388     src/HOL/Real/PReal.thy ~> src/HOL/
  2389     src/HOL/Real/Rational.thy ~> src/HOL/
  2390     src/HOL/Real/RComplete.thy ~> src/HOL/
  2391     src/HOL/Real/RealDef.thy ~> src/HOL/
  2392     src/HOL/Real/RealPow.thy ~> src/HOL/
  2393     src/HOL/Real/Real.thy ~> src/HOL/
  2394     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  2395     src/HOL/Complex/Complex.thy ~> src/HOL/
  2396     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  2397     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  2398     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  2399     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  2400     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  2401     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  2402     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  2403     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  2404     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  2405     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  2406     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  2407     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  2408     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  2409     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  2410     src/HOL/Real/Float ~> src/HOL/Library/
  2411     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  2412     src/HOL/Real/RealVector.thy ~> src/HOL/
  2413 
  2414     src/HOL/arith_data.ML ~> src/HOL/Tools
  2415     src/HOL/hologic.ML ~> src/HOL/Tools
  2416     src/HOL/simpdata.ML ~> src/HOL/Tools
  2417     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  2418     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  2419     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  2420     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  2421     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  2422     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  2423     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  2424 
  2425     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  2426     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  2427     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  2428     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  2429     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  2430     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  2431 
  2432 * If methods "eval" and "evaluation" encounter a structured proof
  2433 state with !!/==>, only the conclusion is evaluated to True (if
  2434 possible), avoiding strange error messages.
  2435 
  2436 * Method "sizechange" automates termination proofs using (a
  2437 modification of) the size-change principle.  Requires SAT solver.  See
  2438 src/HOL/ex/Termination.thy for examples.
  2439 
  2440 * Simplifier: simproc for let expressions now unfolds if bound
  2441 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  2442 
  2443 * Method "arith": Linear arithmetic now ignores all inequalities when
  2444 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  2445 
  2446 * New attribute "arith" for facts that should always be used
  2447 automatically by arithmetic. It is intended to be used locally in
  2448 proofs, e.g.
  2449 
  2450   assumes [arith]: "x > 0"
  2451 
  2452 Global usage is discouraged because of possible performance impact.
  2453 
  2454 * New classes "top" and "bot" with corresponding operations "top" and
  2455 "bot" in theory Orderings; instantiation of class "complete_lattice"
  2456 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  2457 
  2458 * Changed definition lemma "less_fun_def" in order to provide an
  2459 instance for preorders on functions; use lemma "less_le" instead.
  2460 INCOMPATIBILITY.
  2461 
  2462 * Theory Orderings: class "wellorder" moved here, with explicit
  2463 induction rule "less_induct" as assumption.  For instantiation of
  2464 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  2465 INCOMPATIBILITY.
  2466 
  2467 * Theory Orderings: added class "preorder" as superclass of "order".
  2468 INCOMPATIBILITY: Instantiation proofs for order, linorder
  2469 etc. slightly changed.  Some theorems named order_class.* now named
  2470 preorder_class.*.
  2471 
  2472 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  2473 "diag" to "Id_on".
  2474 
  2475 * Theory Finite_Set: added a new fold combinator of type
  2476 
  2477   ('a => 'b => 'b) => 'b => 'a set => 'b
  2478 
  2479 Occasionally this is more convenient than the old fold combinator
  2480 which is now defined in terms of the new one and renamed to
  2481 fold_image.
  2482 
  2483 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  2484 and "ring_simps" have been replaced by "algebra_simps" (which can be
  2485 extended with further lemmas!).  At the moment both still exist but
  2486 the former will disappear at some point.
  2487 
  2488 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  2489 class recpower.  Type-specific simp rules for various recpower types
  2490 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  2491 
  2492 rat_power_0    -> power_0
  2493 rat_power_Suc  -> power_Suc
  2494 realpow_0      -> power_0
  2495 realpow_Suc    -> power_Suc
  2496 complexpow_0   -> power_0
  2497 complexpow_Suc -> power_Suc
  2498 power_poly_0   -> power_0
  2499 power_poly_Suc -> power_Suc
  2500 
  2501 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  2502 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  2503 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  2504 of lemmas from Divides has been generalized from nat to class
  2505 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  2506 renames resulting from duplicate elimination:
  2507 
  2508     dvd_def_mod ~>          dvd_eq_mod_eq_0
  2509     zero_dvd_iff ~>         dvd_0_left_iff
  2510     dvd_0 ~>                dvd_0_right
  2511     DIVISION_BY_ZERO_DIV ~> div_by_0
  2512     DIVISION_BY_ZERO_MOD ~> mod_by_0
  2513     mult_div ~>             div_mult_self2_is_id
  2514     mult_mod ~>             mod_mult_self2_is_0
  2515 
  2516 * Theory IntDiv: removed many lemmas that are instances of class-based
  2517 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  2518 rename old lemmas as follows:
  2519 
  2520 dvd_diff               -> nat_dvd_diff
  2521 dvd_zminus_iff         -> dvd_minus_iff
  2522 mod_add1_eq            -> mod_add_eq
  2523 mod_mult1_eq           -> mod_mult_right_eq
  2524 mod_mult1_eq'          -> mod_mult_left_eq
  2525 mod_mult_distrib_mod   -> mod_mult_eq
  2526 nat_mod_add_left_eq    -> mod_add_left_eq
  2527 nat_mod_add_right_eq   -> mod_add_right_eq
  2528 nat_mod_div_trivial    -> mod_div_trivial
  2529 nat_mod_mod_trivial    -> mod_mod_trivial
  2530 zdiv_zadd_self1        -> div_add_self1
  2531 zdiv_zadd_self2        -> div_add_self2
  2532 zdiv_zmult_self1       -> div_mult_self2_is_id
  2533 zdiv_zmult_self2       -> div_mult_self1_is_id
  2534 zdvd_triv_left         -> dvd_triv_left
  2535 zdvd_triv_right        -> dvd_triv_right
  2536 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  2537 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  2538 zmod_zadd_left_eq      -> mod_add_left_eq
  2539 zmod_zadd_right_eq     -> mod_add_right_eq
  2540 zmod_zadd_self1        -> mod_add_self1
  2541 zmod_zadd_self2        -> mod_add_self2
  2542 zmod_zadd1_eq          -> mod_add_eq
  2543 zmod_zdiff1_eq         -> mod_diff_eq
  2544 zmod_zdvd_zmod         -> mod_mod_cancel
  2545 zmod_zmod_cancel       -> mod_mod_cancel
  2546 zmod_zmult_self1       -> mod_mult_self2_is_0
  2547 zmod_zmult_self2       -> mod_mult_self1_is_0
  2548 zmod_1                 -> mod_by_1
  2549 zdiv_1                 -> div_by_1
  2550 zdvd_abs1              -> abs_dvd_iff
  2551 zdvd_abs2              -> dvd_abs_iff
  2552 zdvd_refl              -> dvd_refl
  2553 zdvd_trans             -> dvd_trans
  2554 zdvd_zadd              -> dvd_add
  2555 zdvd_zdiff             -> dvd_diff
  2556 zdvd_zminus_iff        -> dvd_minus_iff
  2557 zdvd_zminus2_iff       -> minus_dvd_iff
  2558 zdvd_zmultD            -> dvd_mult_right
  2559 zdvd_zmultD2           -> dvd_mult_left
  2560 zdvd_zmult_mono        -> mult_dvd_mono
  2561 zdvd_0_right           -> dvd_0_right
  2562 zdvd_0_left            -> dvd_0_left_iff
  2563 zdvd_1_left            -> one_dvd
  2564 zminus_dvd_iff         -> minus_dvd_iff
  2565 
  2566 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  2567 
  2568 * The real numbers offer decimal input syntax: 12.34 is translated
  2569 into 1234/10^2. This translation is not reversed upon output.
  2570 
  2571 * Theory Library/Polynomial defines an abstract type 'a poly of
  2572 univariate polynomials with coefficients of type 'a.  In addition to
  2573 the standard ring operations, it also supports div and mod.  Code
  2574 generation is also supported, using list-style constructors.
  2575 
  2576 * Theory Library/Inner_Product defines a class of real_inner for real
  2577 inner product spaces, with an overloaded operation inner :: 'a => 'a
  2578 => real.  Class real_inner is a subclass of real_normed_vector from
  2579 theory RealVector.
  2580 
  2581 * Theory Library/Product_Vector provides instances for the product
  2582 type 'a * 'b of several classes from RealVector and Inner_Product.
  2583 Definitions of addition, subtraction, scalar multiplication, norms,
  2584 and inner products are included.
  2585 
  2586 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  2587 addition to the field operations, numerals and case syntax are also
  2588 supported.
  2589 
  2590 * Theory Library/Diagonalize provides constructive version of Cantor's
  2591 first diagonalization argument.
  2592 
  2593 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  2594 zlcm (for int); carried together from various gcd/lcm developements in
  2595 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  2596 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  2597 may recover tupled syntax as follows:
  2598 
  2599     hide (open) const gcd
  2600     abbreviation gcd where
  2601       "gcd == (%(a, b). GCD.gcd a b)"
  2602     notation (output)
  2603       GCD.gcd ("gcd '(_, _')")
  2604 
  2605 The same works for lcm, zgcd, zlcm.
  2606 
  2607 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  2608 instantiations for algebraic structures.  Removed some duplicate
  2609 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  2610 
  2611 * ML antiquotation @{code} takes a constant as argument and generates
  2612 corresponding code in background and inserts name of the corresponding
  2613 resulting ML value/function/datatype constructor binding in place.
  2614 All occurrences of @{code} with a single ML block are generated
  2615 simultaneously.  Provides a generic and safe interface for
  2616 instrumentalizing code generation.  See
  2617 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  2618 In future you ought to refrain from ad-hoc compiling generated SML
  2619 code on the ML toplevel.  Note that (for technical reasons) @{code}
  2620 cannot refer to constants for which user-defined serializations are
  2621 set.  Refer to the corresponding ML counterpart directly in that
  2622 cases.
  2623 
  2624 * Command 'rep_datatype': instead of theorem names the command now
  2625 takes a list of terms denoting the constructors of the type to be
  2626 represented as datatype.  The characteristic theorems have to be
  2627 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  2628 have disappeared in favour of existing ones:
  2629 
  2630     unit_induct                 ~> unit.induct
  2631     prod_induct                 ~> prod.induct
  2632     sum_induct                  ~> sum.induct
  2633     Suc_Suc_eq                  ~> nat.inject
  2634     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  2635 
  2636 
  2637 *** HOL-Algebra ***
  2638 
  2639 * New locales for orders and lattices where the equivalence relation
  2640 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  2641 locales use a record structure with field eq for the equivalence.
  2642 
  2643 * New theory of factorial domains.
  2644 
  2645 * Units_l_inv and Units_r_inv are now simp rules by default.
  2646 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  2647 and/or r_inv will now also require deletion of these lemmas.
  2648 
  2649 * Renamed the following theorems, INCOMPATIBILITY:
  2650 
  2651 UpperD ~> Upper_memD
  2652 LowerD ~> Lower_memD
  2653 least_carrier ~> least_closed
  2654 greatest_carrier ~> greatest_closed
  2655 greatest_Lower_above ~> greatest_Lower_below
  2656 one_zero ~> carrier_one_zero
  2657 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  2658 
  2659 
  2660 *** HOL-Nominal ***
  2661 
  2662 * Nominal datatypes can now contain type-variables.
  2663 
  2664 * Commands 'nominal_inductive' and 'equivariance' work with local
  2665 theory targets.
  2666 
  2667 * Nominal primrec can now works with local theory targets and its
  2668 specification syntax now conforms to the general format as seen in
  2669 'inductive' etc.
  2670 
  2671 * Method "perm_simp" honours the standard simplifier attributes
  2672 (no_asm), (no_asm_use) etc.
  2673 
  2674 * The new predicate #* is defined like freshness, except that on the
  2675 left hand side can be a set or list of atoms.
  2676 
  2677 * Experimental command 'nominal_inductive2' derives strong induction
  2678 principles for inductive definitions.  In contrast to
  2679 'nominal_inductive', which can only deal with a fixed number of
  2680 binders, it can deal with arbitrary expressions standing for sets of
  2681 atoms to be avoided.  The only inductive definition we have at the
  2682 moment that needs this generalisation is the typing rule for Lets in
  2683 the algorithm W:
  2684 
  2685  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  2686  -----------------------------------------------------------------
  2687          Gamma |- Let x be t1 in t2 : T2
  2688 
  2689 In this rule one wants to avoid all the binders that are introduced by
  2690 "close Gamma T1".  We are looking for other examples where this
  2691 feature might be useful.  Please let us know.
  2692 
  2693 
  2694 *** HOLCF ***
  2695 
  2696 * Reimplemented the simplification procedure for proving continuity
  2697 subgoals.  The new simproc is extensible; users can declare additional
  2698 continuity introduction rules with the attribute [cont2cont].
  2699 
  2700 * The continuity simproc now uses a different introduction rule for
  2701 solving continuity subgoals on terms with lambda abstractions.  In
  2702 some rare cases the new simproc may fail to solve subgoals that the
  2703 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  2704 Potential INCOMPATIBILITY.
  2705 
  2706 * Command 'fixrec': specification syntax now conforms to the general
  2707 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  2708 examples.  INCOMPATIBILITY.
  2709 
  2710 
  2711 *** ZF ***
  2712 
  2713 * Proof of Zorn's Lemma for partial orders.
  2714 
  2715 
  2716 *** ML ***
  2717 
  2718 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  2719 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  2720 depends on multithreading, so timouts will not work before Poly/ML
  2721 5.2.1!
  2722 
  2723 * High-level support for concurrent ML programming, see
  2724 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  2725 particularly convenient to organize independent functional
  2726 computations.  The concept of "synchronized variables" provides a
  2727 higher-order interface for components with shared state, avoiding the
  2728 delicate details of mutexes and condition variables.  (Requires
  2729 Poly/ML 5.2.1 or later.)
  2730 
  2731 * ML bindings produced via Isar commands are stored within the Isar
  2732 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2733 become thread-safe and work with undo as expected (concerning
  2734 top-level bindings, not side-effects on global references).
  2735 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2736 compiler at runtime; really global bindings need to be given outside a
  2737 theory.  (Requires Poly/ML 5.2 or later.)
  2738 
  2739 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2740 context.  Top-level ML bindings are stored within the proof context in
  2741 a purely sequential fashion, disregarding the nested proof structure.
  2742 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2743 proof.  (Requires Poly/ML 5.2 or later.)
  2744 
  2745 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2746 and Method.setup, as well as Isar commands 'attribute_setup' and
  2747 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2748 existing code accordingly, or use plain 'setup' together with old
  2749 Method.add_method.
  2750 
  2751 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2752 to 'a -> thm, while results are always tagged with an authentic oracle
  2753 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2754 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2755 accordingly.  Note that extra performance may be gained by producing
  2756 the cterm carefully, avoiding slow Thm.cterm_of.
  2757 
  2758 * Simplified interface for defining document antiquotations via
  2759 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2760 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2761 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2762 examples.
  2763 
  2764 * More systematic treatment of long names, abstract name bindings, and
  2765 name space operations.  Basic operations on qualified names have been
  2766 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2767 Long_Name.append.  Old type bstring has been mostly replaced by
  2768 abstract type binding (see structure Binding), which supports precise
  2769 qualification by packages and local theory targets, as well as proper
  2770 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2771 bstring values into Binding.name, or better pass through abstract
  2772 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2773 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2774 
  2775 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2776 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2777 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2778 
  2779 * Disposed old type and term read functions (Sign.read_def_typ,
  2780 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2781 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2782 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2783 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2784 resort for legacy applications.
  2785 
  2786 * Disposed old declarations, tactics, tactic combinators that refer to
  2787 the simpset or claset of an implicit theory (such as Addsimps,
  2788 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2789 embedded ML text, or local_simpset_of with a proper context passed as
  2790 explicit runtime argument.
  2791 
  2792 * Rules and tactics that read instantiations (read_instantiate,
  2793 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2794 context, which is required for parsing and type-checking.  Moreover,
  2795 the variables are specified as plain indexnames, not string encodings
  2796 thereof.  INCOMPATIBILITY.
  2797 
  2798 * Generic Toplevel.add_hook interface allows to analyze the result of
  2799 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2800 for theorem dependency output of transactions resulting in a new
  2801 theory state.
  2802 
  2803 * ML antiquotations: block-structured compilation context indicated by
  2804 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2805 
  2806   @{binding name}                         - basic name binding
  2807   @{let ?pat = term}                      - term abbreviation (HO matching)
  2808   @{note name = fact}                     - fact abbreviation
  2809   @{thm fact}                             - singleton fact (with attributes)
  2810   @{thms fact}                            - general fact (with attributes)
  2811   @{lemma prop by method}                 - singleton goal
  2812   @{lemma prop by meth1 meth2}            - singleton goal
  2813   @{lemma prop1 ... propN by method}      - general goal
  2814   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2815   @{lemma (open) ...}                     - open derivation
  2816 
  2817 
  2818 *** System ***
  2819 
  2820 * The Isabelle "emacs" tool provides a specific interface to invoke
  2821 Proof General / Emacs, with more explicit failure if that is not
  2822 installed (the old isabelle-interface script silently falls back on
  2823 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2824 installation location of the Proof General distribution.
  2825 
  2826 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2827 the Isabelle process into a JVM/Scala application.  See
  2828 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2829 process wrapper has been discontinued.)
  2830 
  2831 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2832 
  2833 * Various status messages (with exact source position information) are
  2834 emitted, if proper markup print mode is enabled.  This allows
  2835 user-interface components to provide detailed feedback on internal
  2836 prover operations.
  2837 
  2838 
  2839 
  2840 New in Isabelle2008 (June 2008)
  2841 -------------------------------
  2842 
  2843 *** General ***
  2844 
  2845 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2846 and updated, with formally checked references as hyperlinks.
  2847 
  2848 * Theory loader: use_thy (and similar operations) no longer set the
  2849 implicit ML context, which was occasionally hard to predict and in
  2850 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2851 provides a proper context already.
  2852 
  2853 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2854 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2855 'use' within a theory file will do the job.
  2856 
  2857 * Name space merge now observes canonical order, i.e. the second space
  2858 is inserted into the first one, while existing entries in the first
  2859 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2860 swap theory imports.
  2861 
  2862 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2863 INCOMPATIBILITY in identifier syntax etc.
  2864 
  2865 * Outer syntax: string tokens no longer admit escaped white space,
  2866 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2867 white space without escapes.
  2868 
  2869 * Outer syntax: string tokens may contain arbitrary character codes
  2870 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2871 "foo_bar".
  2872 
  2873 
  2874 *** Pure ***
  2875 
  2876 * Context-dependent token translations.  Default setup reverts locally
  2877 fixed variables, and adds hilite markup for undeclared frees.
  2878 
  2879 * Unused theorems can be found using the new command 'unused_thms'.
  2880 There are three ways of invoking it:
  2881 
  2882 (1) unused_thms
  2883      Only finds unused theorems in the current theory.
  2884 
  2885 (2) unused_thms thy_1 ... thy_n -
  2886      Finds unused theorems in the current theory and all of its ancestors,
  2887      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2888 
  2889 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2890      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2891      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2892      their ancestors.
  2893 
  2894 In order to increase the readability of the list produced by
  2895 unused_thms, theorems that have been created by a particular instance
  2896 of a theory command such as 'inductive' or 'function' are considered
  2897 to belong to the same "group", meaning that if at least one theorem in
  2898 this group is used, the other theorems in the same group are no longer
  2899 reported as unused.  Moreover, if all theorems in the group are
  2900 unused, only one theorem in the group is displayed.
  2901 
  2902 Note that proof objects have to be switched on in order for
  2903 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2904 usually the case when using Proof General with the default settings).
  2905 
  2906 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2907 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2908 duplicate fact bindings, or even accidental fact duplications.  Note
  2909 that tools may maintain dynamically scoped facts systematically, using
  2910 PureThy.add_thms_dynamic.
  2911 
  2912 * Command 'hide' now allows to hide from "fact" name space as well.
  2913 
  2914 * Eliminated destructive theorem database, simpset, claset, and
  2915 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2916 update of theories within ML code.
  2917 
  2918 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2919 INCOMPATIBILITY, object-logics depending on former Pure require
  2920 additional setup PureThy.old_appl_syntax_setup; object-logics
  2921 depending on former CPure need to refer to Pure.
  2922 
  2923 * Commands 'use' and 'ML' are now purely functional, operating on
  2924 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2925 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2926 INCOMPATIBILITY.
  2927 
  2928 * Command 'setup': discontinued implicit version with ML reference.
  2929 
  2930 * Instantiation target allows for simultaneous specification of class
  2931 instance operations together with an instantiation proof.
  2932 Type-checking phase allows to refer to class operations uniformly.
  2933 See src/HOL/Complex/Complex.thy for an Isar example and
  2934 src/HOL/Library/Eval.thy for an ML example.
  2935 
  2936 * Indexing of literal facts: be more serious about including only
  2937 facts from the visible specification/proof context, but not the
  2938 background context (locale etc.).  Affects `prop` notation and method
  2939 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2940 situations.
  2941 
  2942 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2943 "(open)" option, which used to expose internal bound variables to the
  2944 proof text.
  2945 
  2946 * Isar statements: removed obsolete case "rule_context".
  2947 INCOMPATIBILITY, better use explicit fixes/assumes.
  2948 
  2949 * Locale proofs: default proof step now includes 'unfold_locales';
  2950 hence 'proof' without argument may be used to unfold locale
  2951 predicates.
  2952 
  2953 
  2954 *** Document preparation ***
  2955 
  2956 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2957 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2958 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2959 spot); renamed link color from "darkblue" to "linkcolor" (default
  2960 value unchanged, can be redefined via \definecolor); no longer sets
  2961 "a4paper" option (unnecessary or even intrusive).
  2962 
  2963 * Antiquotation @{lemma A method} proves proposition A by the given
  2964 method (either a method name or a method name plus (optional) method
  2965 arguments in parentheses) and prints A just like @{prop A}.
  2966 
  2967 
  2968 *** HOL ***
  2969 
  2970 * New primrec package.  Specification syntax conforms in style to
  2971 definition/function/....  No separate induction rule is provided.  The
  2972 "primrec" command distinguishes old-style and new-style specifications
  2973 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2974 When adjusting theories, beware: constants stemming from new-style
  2975 primrec specifications have authentic syntax.
  2976 
  2977 * Metis prover is now an order of magnitude faster, and also works
  2978 with multithreading.
  2979 
  2980 * Metis: the maximum number of clauses that can be produced from a
  2981 theorem is now given by the attribute max_clauses.  Theorems that
  2982 exceed this number are ignored, with a warning printed.
  2983 
  2984 * Sledgehammer no longer produces structured proofs by default. To
  2985 enable, declare [[sledgehammer_full = true]].  Attributes
  2986 reconstruction_modulus, reconstruction_sorts renamed
  2987 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2988 
  2989 * Method "induct_scheme" derives user-specified induction rules
  2990 from well-founded induction and completeness of patterns. This factors
  2991 out some operations that are done internally by the function package
  2992 and makes them available separately.  See
  2993 src/HOL/ex/Induction_Scheme.thy for examples.
  2994 
  2995 * More flexible generation of measure functions for termination
  2996 proofs: Measure functions can be declared by proving a rule of the
  2997 form "is_measure f" and giving it the [measure_function] attribute.
  2998 The "is_measure" predicate is logically meaningless (always true), and
  2999 just guides the heuristic.  To find suitable measure functions, the
  3000 termination prover sets up the goal "is_measure ?f" of the appropriate
  3001 type and generates all solutions by prolog-style backwards proof using
  3002 the declared rules.
  3003 
  3004 This setup also deals with rules like 
  3005 
  3006   "is_measure f ==> is_measure (list_size f)"
  3007 
  3008 which accommodates nested datatypes that recurse through lists.
  3009 Similar rules are predeclared for products and option types.
  3010 
  3011 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  3012 
  3013   INCOMPATIBILITIES:
  3014 
  3015   - Definitions of overloaded constants on sets have to be replaced by
  3016     definitions on => and bool.
  3017 
  3018   - Some definitions of overloaded operators on sets can now be proved
  3019     using the definitions of the operators on => and bool.  Therefore,
  3020     the following theorems have been renamed:
  3021 
  3022       subset_def   -> subset_eq
  3023       psubset_def  -> psubset_eq
  3024       set_diff_def -> set_diff_eq
  3025       Compl_def    -> Compl_eq
  3026       Sup_set_def  -> Sup_set_eq
  3027       Inf_set_def  -> Inf_set_eq
  3028       sup_set_def  -> sup_set_eq
  3029       inf_set_def  -> inf_set_eq
  3030 
  3031   - Due to the incompleteness of the HO unification algorithm, some
  3032     rules such as subst may require manual instantiation, if some of
  3033     the unknowns in the rule is a set.
  3034 
  3035   - Higher order unification and forward proofs:
  3036     The proof pattern
  3037 
  3038       have "P (S::'a set)" <...>
  3039       then have "EX S. P S" ..
  3040 
  3041     no longer works (due to the incompleteness of the HO unification
  3042     algorithm) and must be replaced by the pattern
  3043 
  3044       have "EX S. P S"
  3045       proof
  3046         show "P S" <...>
  3047       qed
  3048 
  3049   - Calculational reasoning with subst (or similar rules):
  3050     The proof pattern
  3051 
  3052       have "P (S::'a set)" <...>
  3053       also have "S = T" <...>
  3054       finally have "P T" .
  3055 
  3056     no longer works (for similar reasons as the previous example) and
  3057     must be replaced by something like
  3058 
  3059       have "P (S::'a set)" <...>
  3060       moreover have "S = T" <...>
  3061       ultimately have "P T" by simp
  3062 
  3063   - Tactics or packages written in ML code:
  3064     Code performing pattern matching on types via
  3065 
  3066       Type ("set", [T]) => ...
  3067 
  3068     must be rewritten. Moreover, functions like strip_type or
  3069     binder_types no longer return the right value when applied to a
  3070     type of the form
  3071 
  3072       T1 => ... => Tn => U => bool
  3073 
  3074     rather than
  3075 
  3076       T1 => ... => Tn => U set
  3077 
  3078 * Merged theories Wellfounded_Recursion, Accessible_Part and
  3079 Wellfounded_Relations to theory Wellfounded.
  3080 
  3081 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  3082 
  3083 * Class finite no longer treats UNIV as class parameter.  Use class
  3084 enum from theory Library/Enum instead to achieve a similar effect.
  3085 INCOMPATIBILITY.
  3086 
  3087 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  3088 and "Cons".  INCOMPATIBILITY.
  3089 
  3090 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  3091 Potential INCOMPATIBILITY.
  3092 
  3093 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  3094 injective_fst_snd removed, use split_eta and prod_eqI instead.
  3095 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  3096 
  3097 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  3098 the same name in theory Orderings:
  3099 
  3100   less_trans
  3101   less_linear
  3102   le_imp_less_or_eq
  3103   le_less_trans
  3104   less_le_trans
  3105   less_not_sym
  3106   less_asym
  3107 
  3108 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  3109 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  3110 and different variable names.
  3111 
  3112 * Library/Option_ord.thy: Canonical order on option type.
  3113 
  3114 * Library/RBT.thy: Red-black trees, an efficient implementation of
  3115 finite maps.
  3116 
  3117 * Library/Countable.thy: Type class for countable types.
  3118 
  3119 * Theory Int: The representation of numerals has changed.  The infix
  3120 operator BIT and the bit datatype with constructors B0 and B1 have
  3121 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  3122 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  3123 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  3124 accordingly.
  3125 
  3126 * Theory Nat: definition of <= and < on natural numbers no longer
  3127 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  3128 le_def and less_def have disappeared.  Consider lemmas not_less
  3129 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  3130 
  3131 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  3132 (whose purpose mainly is for various fold_set functionals) have been
  3133 abandoned in favor of the existing algebraic classes
  3134 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  3135 lower_semilattice (resp. upper_semilattice) and linorder.
  3136 INCOMPATIBILITY.
  3137 
  3138 * Theory Transitive_Closure: induct and cases rules now declare proper
  3139 case_names ("base" and "step").  INCOMPATIBILITY.
  3140 
  3141 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  3142 lattices.  The form set-specific version is available as
  3143 Inductive.lfp_ordinal_induct_set.
  3144 
  3145 * Renamed theorems "power.simps" to "power_int.simps".
  3146 INCOMPATIBILITY.
  3147 
  3148 * Class semiring_div provides basic abstract properties of semirings
  3149 with division and modulo operations.  Subsumes former class dvd_mod.
  3150 
  3151 * Merged theories IntDef, Numeral and IntArith into unified theory
  3152 Int.  INCOMPATIBILITY.
  3153 
  3154 * Theory Library/Code_Index: type "index" now represents natural
  3155 numbers rather than integers.  INCOMPATIBILITY.
  3156 
  3157 * New class "uminus" with operation "uminus" (split of from class
  3158 "minus" which now only has operation "minus", binary).
  3159 INCOMPATIBILITY.
  3160 
  3161 * Constants "card", "internal_split", "option_map" now with authentic
  3162 syntax.  INCOMPATIBILITY.
  3163 
  3164 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  3165 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  3166 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  3167 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  3168 Sup_set_def, le_def, less_def, option_map_def now with object
  3169 equality.  INCOMPATIBILITY.
  3170 
  3171 * Records. Removed K_record, and replaced it by pure lambda term
  3172 %x. c. The simplifier setup is now more robust against eta expansion.
  3173 INCOMPATIBILITY: in cases explicitly referring to K_record.
  3174 
  3175 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  3176 
  3177 * Library/ListVector: new theory of arithmetic vector operations.
  3178 
  3179 * Library/Order_Relation: new theory of various orderings as sets of
  3180 pairs.  Defines preorders, partial orders, linear orders and
  3181 well-orders on sets and on types.
  3182 
  3183 
  3184 *** ZF ***
  3185 
  3186 * Renamed some theories to allow to loading both ZF and HOL in the
  3187 same session:
  3188 
  3189   Datatype  -> Datatype_ZF
  3190   Inductive -> Inductive_ZF
  3191   Int       -> Int_ZF
  3192   IntDiv    -> IntDiv_ZF
  3193   Nat       -> Nat_ZF
  3194   List      -> List_ZF
  3195   Main      -> Main_ZF
  3196 
  3197 INCOMPATIBILITY: ZF theories that import individual theories below
  3198 Main might need to be adapted.  Regular theory Main is still
  3199 available, as trivial extension of Main_ZF.
  3200 
  3201 
  3202 *** ML ***
  3203 
  3204 * ML within Isar: antiquotation @{const name} or @{const
  3205 name(typargs)} produces statically-checked Const term.
  3206 
  3207 * Functor NamedThmsFun: data is available to the user as dynamic fact
  3208 (of the same name).  Removed obsolete print command.
  3209 
  3210 * Removed obsolete "use_legacy_bindings" function.
  3211 
  3212 * The ``print mode'' is now a thread-local value derived from a global
  3213 template (the former print_mode reference), thus access becomes
  3214 non-critical.  The global print_mode reference is for session
  3215 management only; user-code should use print_mode_value,
  3216 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  3217 
  3218 * Functions system/system_out provide a robust way to invoke external
  3219 shell commands, with propagation of interrupts (requires Poly/ML
  3220 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  3221 
  3222 
  3223 *** System ***
  3224 
  3225 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  3226 in accordance with Proof General 3.7, which prefers GNU emacs.
  3227 
  3228 * isatool tty runs Isabelle process with plain tty interaction;
  3229 optional line editor may be specified via ISABELLE_LINE_EDITOR
  3230 setting, the default settings attempt to locate "ledit" and "rlwrap".
  3231 
  3232 * isatool browser now works with Cygwin as well, using general
  3233 "javapath" function defined in Isabelle process environment.
  3234 
  3235 * YXML notation provides a simple and efficient alternative to
  3236 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  3237 isatool yxml as described in the Isabelle system manual.
  3238 
  3239 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  3240 provides general wrapper for managing an Isabelle process in a robust
  3241 fashion, with ``cooked'' output from stdin/stderr.
  3242 
  3243 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  3244 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  3245 
  3246 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  3247 way of changing the user's settings is via
  3248 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  3249 script.
  3250 
  3251 * Multithreading.max_threads := 0 refers to the number of actual CPU
  3252 cores of the underlying machine, which is a good starting point for
  3253 optimal performance tuning.  The corresponding usedir option -M allows
  3254 "max" as an alias for "0".  WARNING: does not work on certain versions
  3255 of Mac OS (with Poly/ML 5.1).
  3256 
  3257 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  3258 adverse effect of Isabelle flooding interactive front-ends (notably
  3259 ProofGeneral / XEmacs).
  3260 
  3261 
  3262 
  3263 New in Isabelle2007 (November 2007)
  3264 -----------------------------------
  3265 
  3266 *** General ***
  3267 
  3268 * More uniform information about legacy features, notably a
  3269 warning/error of "Legacy feature: ...", depending on the state of the
  3270 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  3271 legacy features will disappear eventually.
  3272 
  3273 * Theory syntax: the header format ``theory A = B + C:'' has been
  3274 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  3275 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  3276 
  3277 * Theory syntax: the old non-Isar theory file format has been
  3278 discontinued altogether.  Note that ML proof scripts may still be used
  3279 with Isar theories; migration is usually quite simple with the ML
  3280 function use_legacy_bindings.  INCOMPATIBILITY.
  3281 
  3282 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  3283 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  3284 quotes.
  3285 
  3286 * Theory loader: be more serious about observing the static theory
  3287 header specifications (including optional directories), but not the
  3288 accidental file locations of previously successful loads.  The strict
  3289 update policy of former update_thy is now already performed by
  3290 use_thy, so the former has been removed; use_thys updates several
  3291 theories simultaneously, just as 'imports' within a theory header
  3292 specification, but without merging the results.  Potential
  3293 INCOMPATIBILITY: may need to refine theory headers and commands
  3294 ROOT.ML which depend on load order.
  3295 
  3296 * Theory loader: optional support for content-based file
  3297 identification, instead of the traditional scheme of full physical
  3298 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  3299 (cf. the system manual).  The new scheme allows to work with
  3300 non-finished theories in persistent session images, such that source
  3301 files may be moved later on without requiring reloads.
  3302 
  3303 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3304 file (with the same base name as the theory) are considered a legacy
  3305 feature, which will disappear eventually. Even now, the theory loader
  3306 no longer maintains dependencies on such files.
  3307 
  3308 * Syntax: the scope for resolving ambiguities via type-inference is
  3309 now limited to individual terms, instead of whole simultaneous
  3310 specifications as before. This greatly reduces the complexity of the
  3311 syntax module and improves flexibility by separating parsing and
  3312 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  3313 'fixes' etc.) are required in rare situations.
  3314 
  3315 * Syntax: constants introduced by new-style packages ('definition',
  3316 'abbreviation' etc.) are passed through the syntax module in
  3317 ``authentic mode''. This means that associated mixfix annotations
  3318 really stick to such constants, independently of potential name space
  3319 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  3320 trees are represented slightly differently, may need to adapt syntax
  3321 translations accordingly. Use CONST marker in 'translations' and
  3322 @{const_syntax} antiquotation in 'parse_translation' etc.
  3323 
  3324 * Legacy goal package: reduced interface to the bare minimum required
  3325 to keep existing proof scripts running.  Most other user-level
  3326 functions are now part of the OldGoals structure, which is *not* open
  3327 by default (consider isatool expandshort before open OldGoals).
  3328 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  3329 these tend to cause confusion about the actual goal (!) context being
  3330 used here, which is not necessarily the same as the_context().
  3331 
  3332 * Command 'find_theorems': supports "*" wild-card in "name:"
  3333 criterion; "with_dups" option.  Certain ProofGeneral versions might
  3334 support a specific search form (see ProofGeneral/CHANGES).
  3335 
  3336 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  3337 by default, which means that "prems" (and also "fixed variables") are
  3338 suppressed from proof state output.  Note that the ProofGeneral
  3339 settings mechanism allows to change and save options persistently, but
  3340 older versions of Isabelle will fail to start up if a negative prems
  3341 limit is imposed.
  3342 
  3343 * Local theory targets may be specified by non-nested blocks of
  3344 ``context/locale/class ... begin'' followed by ``end''.  The body may
  3345 contain definitions, theorems etc., including any derived mechanism
  3346 that has been implemented on top of these primitives.  This concept
  3347 generalizes the existing ``theorem (in ...)'' towards more versatility
  3348 and scalability.
  3349 
  3350 * Proof General interface: proper undo of final 'end' command;
  3351 discontinued Isabelle/classic mode (ML proof scripts).
  3352 
  3353 
  3354 *** Document preparation ***
  3355 
  3356 * Added antiquotation @{theory name} which prints the given name,
  3357 after checking that it refers to a valid ancestor theory in the
  3358 current context.
  3359 
  3360 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  3361 check the given source text as ML type/structure, printing verbatim.
  3362 
  3363 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  3364 "c args == rhs" given in the current context.  (Any number of
  3365 arguments may be given on the LHS.)
  3366 
  3367 
  3368 *** Pure ***
  3369 
  3370 * The 'class' package offers a combination of axclass and locale to
  3371 achieve Haskell-like type classes in Isabelle.  Definitions and
  3372 theorems within a class context produce both relative results (with
  3373 implicit parameters according to the locale context), and polymorphic
  3374 constants with qualified polymorphism (according to the class
  3375 context).  Within the body context of a 'class' target, a separate
  3376 syntax layer ("user space type system") takes care of converting
  3377 between global polymorphic consts and internal locale representation.
  3378 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  3379 "isatool doc classes" provides a tutorial.
  3380 
  3381 * Generic code generator framework allows to generate executable
  3382 code for ML and Haskell (including Isabelle classes).  A short usage
  3383 sketch:
  3384 
  3385     internal compilation:
  3386         export_code <list of constants (term syntax)> in SML
  3387     writing SML code to a file:
  3388         export_code <list of constants (term syntax)> in SML <filename>
  3389     writing OCaml code to a file:
  3390         export_code <list of constants (term syntax)> in OCaml <filename>
  3391     writing Haskell code to a bunch of files:
  3392         export_code <list of constants (term syntax)> in Haskell <filename>
  3393 
  3394     evaluating closed propositions to True/False using code generation:
  3395         method ``eval''
  3396 
  3397 Reasonable default setup of framework in HOL.
  3398 
  3399 Theorem attributs for selecting and transforming function equations theorems:
  3400 
  3401     [code fun]:        select a theorem as function equation for a specific constant
  3402     [code fun del]:    deselect a theorem as function equation for a specific constant
  3403     [code inline]:     select an equation theorem for unfolding (inlining) in place
  3404     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  3405 
  3406 User-defined serializations (target in {SML, OCaml, Haskell}):
  3407 
  3408     code_const <and-list of constants (term syntax)>
  3409       {(target) <and-list of const target syntax>}+
  3410 
  3411     code_type <and-list of type constructors>
  3412       {(target) <and-list of type target syntax>}+
  3413 
  3414     code_instance <and-list of instances>
  3415       {(target)}+
  3416         where instance ::= <type constructor> :: <class>
  3417 
  3418     code_class <and_list of classes>
  3419       {(target) <and-list of class target syntax>}+
  3420         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  3421 
  3422 code_instance and code_class only are effective to target Haskell.
  3423 
  3424 For example usage see src/HOL/ex/Codegenerator.thy and
  3425 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  3426 generation from Isabelle/HOL theories is available via "isatool doc
  3427 codegen".
  3428 
  3429 * Code generator: consts in 'consts_code' Isar commands are now
  3430 referred to by usual term syntax (including optional type
  3431 annotations).
  3432 
  3433 * Command 'no_translations' removes translation rules from theory
  3434 syntax.
  3435 
  3436 * Overloaded definitions are now actually checked for acyclic
  3437 dependencies.  The overloading scheme is slightly more general than
  3438 that of Haskell98, although Isabelle does not demand an exact
  3439 correspondence to type class and instance declarations.
  3440 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  3441 exotic versions of overloading -- at the discretion of the user!
  3442 
  3443 Polymorphic constants are represented via type arguments, i.e. the
  3444 instantiation that matches an instance against the most general
  3445 declaration given in the signature.  For example, with the declaration
  3446 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  3447 as c(nat).  Overloading is essentially simultaneous structural
  3448 recursion over such type arguments.  Incomplete specification patterns
  3449 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  3450 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  3451 Command 'print_theory' outputs the normalized system of recursive
  3452 equations, see section "definitions".
  3453 
  3454 * Configuration options are maintained within the theory or proof
  3455 context (with name and type bool/int/string), providing a very simple
  3456 interface to a poor-man's version of general context data.  Tools may
  3457 declare options in ML (e.g. using Attrib.config_int) and then refer to
  3458 these values using Config.get etc.  Users may change options via an
  3459 associated attribute of the same name.  This form of context
  3460 declaration works particularly well with commands 'declare' or
  3461 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  3462 very easy to avoid global references, which would not observe Isar
  3463 toplevel undo/redo and fail to work with multithreading.
  3464 
  3465 Various global ML references of Pure and HOL have been turned into
  3466 configuration options:
  3467 
  3468   Unify.search_bound		unify_search_bound
  3469   Unify.trace_bound		unify_trace_bound
  3470   Unify.trace_simp		unify_trace_simp
  3471   Unify.trace_types		unify_trace_types
  3472   Simplifier.simp_depth_limit	simp_depth_limit
  3473   Blast.depth_limit		blast_depth_limit
  3474   DatatypeProp.dtK		datatype_distinctness_limit
  3475   fast_arith_neq_limit  	fast_arith_neq_limit
  3476   fast_arith_split_limit	fast_arith_split_limit
  3477 
  3478 * Named collections of theorems may be easily installed as context
  3479 data using the functor NamedThmsFun (see also
  3480 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  3481 attributes; there is also a toplevel print command.  This facility is
  3482 just a common case of general context data, which is the preferred way
  3483 for anything more complex than just a list of facts in canonical
  3484 order.
  3485 
  3486 * Isar: command 'declaration' augments a local theory by generic
  3487 declaration functions written in ML.  This enables arbitrary content
  3488 being added to the context, depending on a morphism that tells the
  3489 difference of the original declaration context wrt. the application
  3490 context encountered later on.
  3491 
  3492 * Isar: proper interfaces for simplification procedures.  Command
  3493 'simproc_setup' declares named simprocs (with match patterns, and body
  3494 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  3495 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  3496 
  3497 * Isar: an extra pair of brackets around attribute declarations
  3498 abbreviates a theorem reference involving an internal dummy fact,
  3499 which will be ignored later --- only the effect of the attribute on
  3500 the background context will persist.  This form of in-place
  3501 declarations is particularly useful with commands like 'declare' and
  3502 'using', for example ``have A using [[simproc a]] by simp''.
  3503 
  3504 * Isar: method "assumption" (and implicit closing of subproofs) now
  3505 takes simple non-atomic goal assumptions into account: after applying
  3506 an assumption as a rule the resulting subgoals are solved by atomic
  3507 assumption steps.  This is particularly useful to finish 'obtain'
  3508 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  3509 without referring to the original premise "!!x. P x ==> thesis" in the
  3510 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  3511 more permissive.
  3512 
  3513 * Isar: implicit use of prems from the Isar proof context is
  3514 considered a legacy feature.  Common applications like ``have A .''
  3515 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  3516 referencing facts explicitly here improves readability and
  3517 maintainability of proof texts.
  3518 
  3519 * Isar: improper proof element 'guess' is like 'obtain', but derives
  3520 the obtained context from the course of reasoning!  For example:
  3521 
  3522   assume "EX x y. A x & B y"   -- "any previous fact"
  3523   then guess x and y by clarify
  3524 
  3525 This technique is potentially adventurous, depending on the facts and
  3526 proof tools being involved here.
  3527 
  3528 * Isar: known facts from the proof context may be specified as literal
  3529 propositions, using ASCII back-quote syntax.  This works wherever
  3530 named facts used to be allowed so far, in proof commands, proof
  3531 methods, attributes etc.  Literal facts are retrieved from the context
  3532 according to unification of type and term parameters.  For example,
  3533 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  3534 theorems in the current context, then these are valid literal facts:
  3535 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  3536 
  3537 There is also a proof method "fact" which does the same composition
  3538 for explicit goal states, e.g. the following proof texts coincide with
  3539 certain special cases of literal facts:
  3540 
  3541   have "A" by fact                 ==  note `A`
  3542   have "A ==> B" by fact           ==  note `A ==> B`
  3543   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  3544   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  3545 
  3546 * Isar: ":" (colon) is no longer a symbolic identifier character in
  3547 outer syntax.  Thus symbolic identifiers may be used without
  3548 additional white space in declarations like this: ``assume *: A''.
  3549 
  3550 * Isar: 'print_facts' prints all local facts of the current context,
  3551 both named and unnamed ones.
  3552 
  3553 * Isar: 'def' now admits simultaneous definitions, e.g.:
  3554 
  3555   def x == "t" and y == "u"
  3556 
  3557 * Isar: added command 'unfolding', which is structurally similar to
  3558 'using', but affects both the goal state and facts by unfolding given
  3559 rewrite rules.  Thus many occurrences of the 'unfold' method or
  3560 'unfolded' attribute may be replaced by first-class proof text.
  3561 
  3562 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  3563 and command 'unfolding' now all support object-level equalities
  3564 (potentially conditional).  The underlying notion of rewrite rule is
  3565 analogous to the 'rule_format' attribute, but *not* that of the
  3566 Simplifier (which is usually more generous).
  3567 
  3568 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  3569 premises of a theorem by n. Useful in conjunction with drule.
  3570 
  3571 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  3572 method expression within a sandbox consisting of the first N
  3573 sub-goals, which need to exist.  For example, ``simp_all [3]''
  3574 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  3575 simplifies all new goals that emerge from applying rule foo to the
  3576 originally first one.
  3577 
  3578 * Isar: schematic goals are no longer restricted to higher-order
  3579 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  3580 expected.
  3581 
  3582 * Isar: the conclusion of a long theorem statement is now either
  3583 'shows' (a simultaneous conjunction, as before), or 'obtains'
  3584 (essentially a disjunction of cases with local parameters and
  3585 assumptions).  The latter allows to express general elimination rules
  3586 adequately; in this notation common elimination rules look like this:
  3587 
  3588   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  3589     assumes "EX x. P x"
  3590     obtains x where "P x"
  3591 
  3592   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  3593     assumes "A & B"
  3594     obtains A and B
  3595 
  3596   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  3597     assumes "A | B"
  3598     obtains
  3599       A
  3600     | B
  3601 
  3602 The subsequent classical rules even refer to the formal "thesis"
  3603 explicitly:
  3604 
  3605   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  3606     obtains "~ thesis"
  3607 
  3608   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  3609     obtains "thesis ==> something"
  3610 
  3611 The actual proof of an 'obtains' statement is analogous to that of the
  3612 Isar proof element 'obtain', only that there may be several cases.
  3613 Optional case names may be specified in parentheses; these will be
  3614 available both in the present proof and as annotations in the
  3615 resulting rule, for later use with the 'cases' method (cf. attribute
  3616 case_names).
  3617 
  3618 * Isar: the assumptions of a long theorem statement are available as
  3619 "assms" fact in the proof context.  This is more appropriate than the
  3620 (historical) "prems", which refers to all assumptions of the current
  3621 context, including those from the target locale, proof body etc.
  3622 
  3623 * Isar: 'print_statement' prints theorems from the current theory or
  3624 proof context in long statement form, according to the syntax of a
  3625 top-level lemma.
  3626 
  3627 * Isar: 'obtain' takes an optional case name for the local context
  3628 introduction rule (default "that").
  3629 
  3630 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  3631 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  3632 to occur.
  3633 
  3634 * Pure: syntax "CONST name" produces a fully internalized constant
  3635 according to the current context.  This is particularly useful for
  3636 syntax translations that should refer to internal constant
  3637 representations independently of name spaces.
  3638 
  3639 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  3640 instead of "FOO ". This allows multiple binder declarations to coexist
  3641 in the same context.  INCOMPATIBILITY.
  3642 
  3643 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  3644 primitive that also works in a locale context (both for constants and
  3645 fixed variables). Type declaration and internal syntactic representation
  3646 of given constants retrieved from the context. Likewise, the
  3647 'no_notation' command allows to remove given syntax annotations from the
  3648 current context.
  3649 
  3650 * Isar/locales: new derived specification elements 'axiomatization',
  3651 'definition', 'abbreviation', which support type-inference, admit
  3652 object-level specifications (equality, equivalence).  See also the
  3653 isar-ref manual.  Examples:
  3654 
  3655   axiomatization
  3656     eq  (infix "===" 50) where
  3657     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  3658 
  3659   definition "f x y = x + y + 1"
  3660   definition g where "g x = f x x"
  3661 
  3662   abbreviation
  3663     neq  (infix "=!=" 50) where
  3664     "x =!= y == ~ (x === y)"
  3665 
  3666 These specifications may be also used in a locale context.  Then the
  3667 constants being introduced depend on certain fixed parameters, and the
  3668 constant name is qualified by the locale base name.  An internal
  3669 abbreviation takes care for convenient input and output, making the
  3670 parameters implicit and using the original short name.  See also
  3671 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  3672 entities from a monomorphic theory.
  3673 
  3674 Presently, abbreviations are only available 'in' a target locale, but
  3675 not inherited by general import expressions.  Also note that
  3676 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  3677 'translations' in common applications.  The "no_abbrevs" print mode
  3678 prevents folding of abbreviations in term output.
  3679 
  3680 Concrete syntax is attached to specified constants in internal form,
  3681 independently of name spaces.  The parse tree representation is
  3682 slightly different -- use 'notation' instead of raw 'syntax', and
  3683 'translations' with explicit "CONST" markup to accommodate this.
  3684 
  3685 * Pure/Isar: unified syntax for new-style specification mechanisms
  3686 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  3687 full type inference and dummy patterns ("_").  For example:
  3688 
  3689   definition "K x _ = x"
  3690 
  3691   inductive conj for A B
  3692   where "A ==> B ==> conj A B"
  3693 
  3694 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  3695 the current context.  Print mode "no_abbrevs" prevents inversion of
  3696 abbreviations on output.
  3697 
  3698 * Isar/locales: improved parameter handling: use of locales "var" and
  3699 "struct" no longer necessary; - parameter renamings are no longer
  3700 required to be injective.  For example, this allows to define
  3701 endomorphisms as locale endom = homom mult mult h.
  3702 
  3703 * Isar/locales: changed the way locales with predicates are defined.
  3704 Instead of accumulating the specification, the imported expression is
  3705 now an interpretation.  INCOMPATIBILITY: different normal form of
  3706 locale expressions.  In particular, in interpretations of locales with
  3707 predicates, goals repesenting already interpreted fragments are not
  3708 removed automatically.  Use methods `intro_locales' and
  3709 `unfold_locales'; see below.
  3710 
  3711 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  3712 provide backward reasoning on locales predicates.  The methods are
  3713 aware of interpretations and discharge corresponding goals.
  3714 `intro_locales' is less aggressive then `unfold_locales' and does not
  3715 unfold predicates to assumptions.
  3716 
  3717 * Isar/locales: the order in which locale fragments are accumulated
  3718 has changed.  This enables to override declarations from fragments due
  3719 to interpretations -- for example, unwanted simp rules.
  3720 
  3721 * Isar/locales: interpretation in theories and proof contexts has been
  3722 extended.  One may now specify (and prove) equations, which are
  3723 unfolded in interpreted theorems.  This is useful for replacing
  3724 defined concepts (constants depending on locale parameters) by
  3725 concepts already existing in the target context.  Example:
  3726 
  3727   interpretation partial_order ["op <= :: [int, int] => bool"]
  3728     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3729 
  3730 Typically, the constant `partial_order.less' is created by a
  3731 definition specification element in the context of locale
  3732 partial_order.
  3733 
  3734 * Method "induct": improved internal context management to support
  3735 local fixes and defines on-the-fly. Thus explicit meta-level
  3736 connectives !!  and ==> are rarely required anymore in inductive goals
  3737 (using object-logic connectives for this purpose has been long
  3738 obsolete anyway). Common proof patterns are explained in
  3739 src/HOL/Induct/Common_Patterns.thy, see also
  3740 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3741 examples.
  3742 
  3743 * Method "induct": improved handling of simultaneous goals. Instead of
  3744 introducing object-level conjunction, the statement is now split into
  3745 several conclusions, while the corresponding symbolic cases are nested
  3746 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3747 see src/HOL/Induct/Common_Patterns.thy, for example.
  3748 
  3749 * Method "induct": mutual induction rules are now specified as a list
  3750 of rule sharing the same induction cases. HOL packages usually provide
  3751 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3752 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3753 mutual induction rules differently, i.e. like this:
  3754 
  3755   (induct rule: foo_bar.inducts)
  3756   (induct set: foo bar)
  3757   (induct pred: foo bar)
  3758   (induct type: foo bar)
  3759 
  3760 The ML function ProjectRule.projections turns old-style rules into the
  3761 new format.
  3762 
  3763 * Method "coinduct": dual of induction, see
  3764 src/HOL/Library/Coinductive_List.thy for various examples.
  3765 
  3766 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3767 considered a legacy feature.
  3768 
  3769 * Attribute "symmetric" produces result with standardized schematic
  3770 variables (index 0).  Potential INCOMPATIBILITY.
  3771 
  3772 * Simplifier: by default the simplifier trace only shows top level
  3773 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3774 default. Thus there is less danger of being flooded by the trace. The
  3775 trace indicates where parts have been suppressed.
  3776   
  3777 * Provers/classical: removed obsolete classical version of elim_format
  3778 attribute; classical elim/dest rules are now treated uniformly when
  3779 manipulating the claset.
  3780 
  3781 * Provers/classical: stricter checks to ensure that supplied intro,
  3782 dest and elim rules are well-formed; dest and elim rules must have at
  3783 least one premise.
  3784 
  3785 * Provers/classical: attributes dest/elim/intro take an optional
  3786 weight argument for the rule (just as the Pure versions).  Weights are
  3787 ignored by automated tools, but determine the search order of single
  3788 rule steps.
  3789 
  3790 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3791 where the body does not mention the bound variable.  Note that dummy
  3792 patterns implicitly depend on their context of bounds, which makes
  3793 "{_. _}" match any set comprehension as expected.  Potential
  3794 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3795 constant "_idtdummy" in the binding position.
  3796 
  3797 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3798 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3799 for example "A -> B" => "Pi A (%_. B)".
  3800 
  3801 * Pure: 'class_deps' command visualizes the subclass relation, using
  3802 the graph browser tool.
  3803 
  3804 * Pure: 'print_theory' now suppresses certain internal declarations by
  3805 default; use '!' option for full details.
  3806 
  3807 
  3808 *** HOL ***
  3809 
  3810 * Method "metis" proves goals by applying the Metis general-purpose
  3811 resolution prover (see also http://gilith.com/software/metis/).
  3812 Examples are in the directory MetisExamples.  WARNING: the
  3813 Isabelle/HOL-Metis integration does not yet work properly with
  3814 multi-threading.
  3815   
  3816 * Command 'sledgehammer' invokes external automatic theorem provers as
  3817 background processes.  It generates calls to the "metis" method if
  3818 successful. These can be pasted into the proof.  Users do not have to
  3819 wait for the automatic provers to return.  WARNING: does not really
  3820 work with multi-threading.
  3821 
  3822 * New "auto_quickcheck" feature tests outermost goal statements for
  3823 potential counter-examples.  Controlled by ML references
  3824 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3825 5000 milliseconds).  Fails silently if statements is outside of
  3826 executable fragment, or any other codgenerator problem occurs.
  3827 
  3828 * New constant "undefined" with axiom "undefined x = undefined".
  3829 
  3830 * Added class "HOL.eq", allowing for code generation with polymorphic
  3831 equality.
  3832 
  3833 * Some renaming of class constants due to canonical name prefixing in
  3834 the new 'class' package:
  3835 
  3836     HOL.abs ~> HOL.abs_class.abs
  3837     HOL.divide ~> HOL.divide_class.divide
  3838     0 ~> HOL.zero_class.zero
  3839     1 ~> HOL.one_class.one
  3840     op + ~> HOL.plus_class.plus
  3841     op - ~> HOL.minus_class.minus
  3842     uminus ~> HOL.minus_class.uminus
  3843     op * ~> HOL.times_class.times
  3844     op < ~> HOL.ord_class.less
  3845     op <= > HOL.ord_class.less_eq
  3846     Nat.power ~> Power.power_class.power
  3847     Nat.size ~> Nat.size_class.size
  3848     Numeral.number_of ~> Numeral.number_class.number_of
  3849     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3850     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3851     Orderings.min ~> Orderings.ord_class.min
  3852     Orderings.max ~> Orderings.ord_class.max
  3853     Divides.op div ~> Divides.div_class.div
  3854     Divides.op mod ~> Divides.div_class.mod
  3855     Divides.op dvd ~> Divides.div_class.dvd
  3856 
  3857 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3858 
  3859 a) User-defined constants using any of the names "plus", "minus",
  3860 "times", "less" or "less_eq". The standard syntax translations for
  3861 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3862 names.
  3863 
  3864 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3865 INCOMPATIBILITY: use more specific names.
  3866 
  3867 c) Permutative equations (e.g. "a + b = b + a")
  3868 Since the change of names also changes the order of terms, permutative
  3869 rewrite rules may get applied in a different order. Experience shows
  3870 that this is rarely the case (only two adaptions in the whole Isabelle
  3871 distribution).  INCOMPATIBILITY: rewrite proofs
  3872 
  3873 d) ML code directly refering to constant names
  3874 This in general only affects hand-written proof tactics, simprocs and
  3875 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3876 Consider using @{const_name} antiquotation.
  3877 
  3878 * New class "default" with associated constant "default".
  3879 
  3880 * Function "sgn" is now overloaded and available on int, real, complex
  3881 (and other numeric types), using class "sgn".  Two possible defs of
  3882 sgn are given as equational assumptions in the classes sgn_if and
  3883 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3884 INCOMPATIBILITY.
  3885 
  3886 * Locale "partial_order" now unified with class "order" (cf. theory
  3887 Orderings), added parameter "less".  INCOMPATIBILITY.
  3888 
  3889 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3890 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3891 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3892 
  3893 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3894 changed order of proof goals in instance proofs.
  3895 
  3896 * The transitivity reasoner for partial and linear orders is set up
  3897 for classes "order" and "linorder".  Instances of the reasoner are available
  3898 in all contexts importing or interpreting the corresponding locales.
  3899 Method "order" invokes the reasoner separately; the reasoner
  3900 is also integrated with the Simplifier as a solver.  Diagnostic
  3901 command 'print_orders' shows the available instances of the reasoner
  3902 in the current context.
  3903 
  3904 * Localized monotonicity predicate in theory "Orderings"; integrated
  3905 lemmas max_of_mono and min_of_mono with this predicate.
  3906 INCOMPATIBILITY.
  3907 
  3908 * Formulation of theorem "dense" changed slightly due to integration
  3909 with new class dense_linear_order.
  3910 
  3911 * Uniform lattice theory development in HOL.
  3912 
  3913     constants "meet" and "join" now named "inf" and "sup"
  3914     constant "Meet" now named "Inf"
  3915 
  3916     classes "meet_semilorder" and "join_semilorder" now named
  3917       "lower_semilattice" and "upper_semilattice"
  3918     class "lorder" now named "lattice"
  3919     class "comp_lat" now named "complete_lattice"
  3920 
  3921     Instantiation of lattice classes allows explicit definitions
  3922     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3923 
  3924   INCOMPATIBILITY.  Theorem renames:
  3925 
  3926     meet_left_le            ~> inf_le1
  3927     meet_right_le           ~> inf_le2
  3928     join_left_le            ~> sup_ge1
  3929     join_right_le           ~> sup_ge2
  3930     meet_join_le            ~> inf_sup_ord
  3931     le_meetI                ~> le_infI
  3932     join_leI                ~> le_supI
  3933     le_meet                 ~> le_inf_iff
  3934     le_join                 ~> ge_sup_conv
  3935     meet_idempotent         ~> inf_idem
  3936     join_idempotent         ~> sup_idem
  3937     meet_comm               ~> inf_commute
  3938     join_comm               ~> sup_commute
  3939     meet_leI1               ~> le_infI1
  3940     meet_leI2               ~> le_infI2
  3941     le_joinI1               ~> le_supI1
  3942     le_joinI2               ~> le_supI2
  3943     meet_assoc              ~> inf_assoc
  3944     join_assoc              ~> sup_assoc
  3945     meet_left_comm          ~> inf_left_commute
  3946     meet_left_idempotent    ~> inf_left_idem
  3947     join_left_comm          ~> sup_left_commute
  3948     join_left_idempotent    ~> sup_left_idem
  3949     meet_aci                ~> inf_aci
  3950     join_aci                ~> sup_aci
  3951     le_def_meet             ~> le_iff_inf
  3952     le_def_join             ~> le_iff_sup
  3953     join_absorp2            ~> sup_absorb2
  3954     join_absorp1            ~> sup_absorb1
  3955     meet_absorp1            ~> inf_absorb1
  3956     meet_absorp2            ~> inf_absorb2
  3957     meet_join_absorp        ~> inf_sup_absorb
  3958     join_meet_absorp        ~> sup_inf_absorb
  3959     distrib_join_le         ~> distrib_sup_le
  3960     distrib_meet_le         ~> distrib_inf_le
  3961 
  3962     add_meet_distrib_left   ~> add_inf_distrib_left
  3963     add_join_distrib_left   ~> add_sup_distrib_left
  3964     is_join_neg_meet        ~> is_join_neg_inf
  3965     is_meet_neg_join        ~> is_meet_neg_sup
  3966     add_meet_distrib_right  ~> add_inf_distrib_right
  3967     add_join_distrib_right  ~> add_sup_distrib_right
  3968     add_meet_join_distribs  ~> add_sup_inf_distribs
  3969     join_eq_neg_meet        ~> sup_eq_neg_inf
  3970     meet_eq_neg_join        ~> inf_eq_neg_sup
  3971     add_eq_meet_join        ~> add_eq_inf_sup
  3972     meet_0_imp_0            ~> inf_0_imp_0
  3973     join_0_imp_0            ~> sup_0_imp_0
  3974     meet_0_eq_0             ~> inf_0_eq_0
  3975     join_0_eq_0             ~> sup_0_eq_0
  3976     neg_meet_eq_join        ~> neg_inf_eq_sup
  3977     neg_join_eq_meet        ~> neg_sup_eq_inf
  3978     join_eq_if              ~> sup_eq_if
  3979 
  3980     mono_meet               ~> mono_inf
  3981     mono_join               ~> mono_sup
  3982     meet_bool_eq            ~> inf_bool_eq
  3983     join_bool_eq            ~> sup_bool_eq
  3984     meet_fun_eq             ~> inf_fun_eq
  3985     join_fun_eq             ~> sup_fun_eq
  3986     meet_set_eq             ~> inf_set_eq
  3987     join_set_eq             ~> sup_set_eq
  3988     meet1_iff               ~> inf1_iff
  3989     meet2_iff               ~> inf2_iff
  3990     meet1I                  ~> inf1I
  3991     meet2I                  ~> inf2I
  3992     meet1D1                 ~> inf1D1
  3993     meet2D1                 ~> inf2D1
  3994     meet1D2                 ~> inf1D2
  3995     meet2D2                 ~> inf2D2
  3996     meet1E                  ~> inf1E
  3997     meet2E                  ~> inf2E
  3998     join1_iff               ~> sup1_iff
  3999     join2_iff               ~> sup2_iff
  4000     join1I1                 ~> sup1I1
  4001     join2I1                 ~> sup2I1
  4002     join1I1                 ~> sup1I1
  4003     join2I2                 ~> sup1I2
  4004     join1CI                 ~> sup1CI
  4005     join2CI                 ~> sup2CI
  4006     join1E                  ~> sup1E
  4007     join2E                  ~> sup2E
  4008 
  4009     is_meet_Meet            ~> is_meet_Inf
  4010     Meet_bool_def           ~> Inf_bool_def
  4011     Meet_fun_def            ~> Inf_fun_def
  4012     Meet_greatest           ~> Inf_greatest
  4013     Meet_lower              ~> Inf_lower
  4014     Meet_set_def            ~> Inf_set_def
  4015 
  4016     Sup_def                 ~> Sup_Inf
  4017     Sup_bool_eq             ~> Sup_bool_def
  4018     Sup_fun_eq              ~> Sup_fun_def
  4019     Sup_set_eq              ~> Sup_set_def
  4020 
  4021     listsp_meetI            ~> listsp_infI
  4022     listsp_meet_eq          ~> listsp_inf_eq
  4023 
  4024     meet_min                ~> inf_min
  4025     join_max                ~> sup_max
  4026 
  4027 * Added syntactic class "size"; overloaded constant "size" now has
  4028 type "'a::size ==> bool"
  4029 
  4030 * Internal reorganisation of `size' of datatypes: size theorems
  4031 "foo.size" are no longer subsumed by "foo.simps" (but are still
  4032 simplification rules by default!); theorems "prod.size" now named
  4033 "*.size".
  4034 
  4035 * Class "div" now inherits from class "times" rather than "type".
  4036 INCOMPATIBILITY.
  4037 
  4038 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  4039 Linorder etc.  have disappeared; operations defined in terms of
  4040 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  4041 
  4042 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  4043 
  4044 * HOL-Word: New extensive library and type for generic, fixed size
  4045 machine words, with arithemtic, bit-wise, shifting and rotating
  4046 operations, reflection into int, nat, and bool lists, automation for
  4047 linear arithmetic (by automatic reflection into nat or int), including
  4048 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  4049 arithmetic type classes, supporting automatic simplification of
  4050 numerals on all operations.
  4051 
  4052 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  4053 
  4054 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  4055 
  4056 * Code generator library theories:
  4057   - Code_Integer represents HOL integers by big integer literals in target
  4058     languages.
  4059   - Code_Char represents HOL characters by character literals in target
  4060     languages.
  4061   - Code_Char_chr like Code_Char, but also offers treatment of character
  4062     codes; includes Code_Integer.
  4063   - Executable_Set allows to generate code for finite sets using lists.
  4064   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  4065     denominator).
  4066   - Executable_Real implements a subset of real numbers, namly those
  4067     representable by rational numbers.
  4068   - Efficient_Nat implements natural numbers by integers, which in general will
  4069     result in higher efficency; pattern matching with 0/Suc is eliminated;
  4070     includes Code_Integer.
  4071   - Code_Index provides an additional datatype index which is mapped to
  4072     target-language built-in integers.
  4073   - Code_Message provides an additional datatype message_string which is isomorphic to
  4074     strings; messages are mapped to target-language strings.
  4075 
  4076 * New package for inductive predicates
  4077 
  4078   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  4079 
  4080     inductive
  4081       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4082       for z_1 :: U_1 and ... and z_n :: U_m
  4083     where
  4084       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4085     | ...
  4086 
  4087   with full support for type-inference, rather than
  4088 
  4089     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4090 
  4091     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4092     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4093 
  4094     inductive "s z_1 ... z_m"
  4095     intros
  4096       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4097       ...
  4098 
  4099   For backward compatibility, there is a wrapper allowing inductive
  4100   sets to be defined with the new package via
  4101 
  4102     inductive_set
  4103       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4104       for z_1 :: U_1 and ... and z_n :: U_m
  4105     where
  4106       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4107     | ...
  4108 
  4109   or
  4110 
  4111     inductive_set
  4112       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4113       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4114       for z_1 :: U_1 and ... and z_n :: U_m
  4115     where
  4116       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4117     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4118     | ...
  4119 
  4120   if the additional syntax "p ..." is required.
  4121 
  4122   Numerous examples can be found in the subdirectories src/HOL/Auth,
  4123   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  4124 
  4125   INCOMPATIBILITIES:
  4126 
  4127   - Since declaration and definition of inductive sets or predicates
  4128     is no longer separated, abbreviations involving the newly
  4129     introduced sets or predicates must be specified together with the
  4130     introduction rules after the 'where' keyword (see above), rather
  4131     than before the actual inductive definition.
  4132 
  4133   - The variables in induction and elimination rules are now
  4134     quantified in the order of their occurrence in the introduction
  4135     rules, rather than in alphabetical order. Since this may break
  4136     some proofs, these proofs either have to be repaired, e.g. by
  4137     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  4138     statements of the form
  4139 
  4140       case (rule_i a_i_1 ... a_i_{k_i})
  4141 
  4142     or the old order of quantification has to be restored by explicitly adding
  4143     meta-level quantifiers in the introduction rules, i.e.
  4144 
  4145       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  4146 
  4147   - The format of the elimination rules is now
  4148 
  4149       p z_1 ... z_m x_1 ... x_n ==>
  4150         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4151         ==> ... ==> P
  4152 
  4153     for predicates and
  4154 
  4155       (x_1, ..., x_n) : s z_1 ... z_m ==>
  4156         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4157         ==> ... ==> P
  4158 
  4159     for sets rather than
  4160 
  4161       x : s z_1 ... z_m ==>
  4162         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  4163         ==> ... ==> P
  4164 
  4165     This may require terms in goals to be expanded to n-tuples
  4166     (e.g. using case_tac or simplification with the split_paired_all
  4167     rule) before the above elimination rule is applicable.
  4168 
  4169   - The elimination or case analysis rules for (mutually) inductive
  4170     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  4171     list of rules "p_1_..._p_k.elims" is no longer available.
  4172 
  4173 * New package "function"/"fun" for general recursive functions,
  4174 supporting mutual and nested recursion, definitions in local contexts,
  4175 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  4176 for small examples, and the separate tutorial on the function
  4177 package. The old recdef "package" is still available as before, but
  4178 users are encouraged to use the new package.
  4179 
  4180 * Method "lexicographic_order" automatically synthesizes termination
  4181 relations as lexicographic combinations of size measures. 
  4182 
  4183 * Case-expressions allow arbitrary constructor-patterns (including
  4184 "_") and take their order into account, like in functional
  4185 programming.  Internally, this is translated into nested
  4186 case-expressions; missing cases are added and mapped to the predefined
  4187 constant "undefined". In complicated cases printing may no longer show
  4188 the original input but the internal form. Lambda-abstractions allow
  4189 the same form of pattern matching: "% pat1 => e1 | ..." is an
  4190 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  4191 variable.
  4192 
  4193 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  4194 is an abbreviation for "of_nat :: nat => int". The simplification
  4195 rules for "of_nat" have been changed to work like "int" did
  4196 previously.  Potential INCOMPATIBILITY:
  4197   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  4198   - of_nat_diff and of_nat_mult are no longer default simp rules
  4199 
  4200 * Method "algebra" solves polynomial equations over (semi)rings using
  4201 Groebner bases. The (semi)ring structure is defined by locales and the
  4202 tool setup depends on that generic context. Installing the method for
  4203 a specific type involves instantiating the locale and possibly adding
  4204 declarations for computation on the coefficients.  The method is
  4205 already instantiated for natural numbers and for the axiomatic class
  4206 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  4207 CALCULEMUS 2007 for the general principles underlying this
  4208 architecture of context-aware proof-tools.
  4209 
  4210 * Method "ferrack" implements quantifier elimination over
  4211 special-purpose dense linear orders using locales (analogous to
  4212 "algebra"). The method is already installed for class
  4213 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  4214 rat, etc.
  4215 
  4216 * Former constant "List.op @" now named "List.append".  Use ML
  4217 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  4218 circumvent possible incompatibilities when working on ML level.
  4219 
  4220 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  4221 
  4222 * New function listsum :: 'a list => 'a for arbitrary monoids.
  4223 Special syntax: "SUM x <- xs. f x" (and latex variants)
  4224 
  4225 * New syntax for Haskell-like list comprehension (input only), eg.
  4226 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  4227 
  4228 * The special syntax for function "filter" has changed from [x :
  4229 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  4230 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  4231 
  4232 * [a..b] is now defined for arbitrary linear orders.  It used to be
  4233 defined on nat only, as an abbreviation for [a..<Suc b]
  4234 INCOMPATIBILITY.
  4235 
  4236 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  4237 
  4238 * New functions "sorted" and "sort" in src/HOL/List.thy.
  4239 
  4240 * New lemma collection field_simps (an extension of ring_simps) for
  4241 manipulating (in)equations involving division. Multiplies with all
  4242 denominators that can be proved to be non-zero (in equations) or
  4243 positive/negative (in inequations).
  4244 
  4245 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  4246 have been improved and renamed to ring_simps, group_simps and
  4247 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  4248 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  4249 
  4250 * Theory Library/Commutative_Ring: switched from recdef to function
  4251 package; constants add, mul, pow now curried.  Infix syntax for
  4252 algebraic operations.
  4253 
  4254 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  4255 INCOMPATIBILITY.
  4256 
  4257 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  4258 INCOMPATIBILITY.
  4259 
  4260 * HOL/records: generalised field-update to take a function on the
  4261 field rather than the new value: r(|A := x|) is translated to A_update
  4262 (K x) r The K-combinator that is internally used is called K_record.
  4263 INCOMPATIBILITY: Usage of the plain update functions has to be
  4264 adapted.
  4265  
  4266 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  4267 * x = 0, which are required for a semiring.  Richer structures do not
  4268 inherit from semiring_0 anymore, because this property is a theorem
  4269 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  4270 there is more to prove, but this is mostly trivial.
  4271 
  4272 * Class "recpower" is generalized to arbitrary monoids, not just
  4273 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  4274 commutativity or semiring properties additionally.
  4275 
  4276 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  4277 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  4278 better use 'abbreviation'.
  4279 
  4280 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  4281 
  4282 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  4283 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  4284 significant changes for setting up numeral syntax for types:
  4285   - New constants Numeral.pred and Numeral.succ instead
  4286       of former Numeral.bin_pred and Numeral.bin_succ.
  4287   - Use integer operations instead of bin_add, bin_mult and so on.
  4288   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  4289   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  4290 
  4291 See src/HOL/Integ/IntArith.thy for an example setup.
  4292 
  4293 * Command 'normal_form' computes the normal form of a term that may
  4294 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  4295 produces ``[b, c, a]'' (without proof).  This command is suitable for
  4296 heavy-duty computations because the functions are compiled to ML
  4297 first.  Correspondingly, a method "normalization" is provided.  See
  4298 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  4299 
  4300 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  4301 25 like -->); output depends on the "iff" print_mode, the default is
  4302 "A = B" (with priority 50).
  4303 
  4304 * Relations less (<) and less_eq (<=) are also available on type bool.
  4305 Modified syntax to disallow nesting without explicit parentheses,
  4306 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  4307 INCOMPATIBILITY.
  4308 
  4309 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  4310 
  4311 * Relation composition operator "op O" now has precedence 75 and binds
  4312 stronger than union and intersection. INCOMPATIBILITY.
  4313 
  4314 * The old set interval syntax "{m..n(}" (and relatives) has been
  4315 removed.  Use "{m..<n}" (and relatives) instead.
  4316 
  4317 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  4318 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  4319 ``declare [[simproc del: neq]]''.
  4320 
  4321 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  4322 True/False.
  4323 
  4324 * Theorem Cons_eq_map_conv no longer declared as "simp".
  4325 
  4326 * Theorem setsum_mult renamed to setsum_right_distrib.
  4327 
  4328 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  4329 ``rule'' method.
  4330 
  4331 * Reimplemented methods "sat" and "satx", with several improvements:
  4332 goals no longer need to be stated as "<prems> ==> False", equivalences
  4333 (i.e. "=" on type bool) are handled, variable names of the form
  4334 "lit_<n>" are no longer reserved, significant speedup.
  4335 
  4336 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  4337 zChaff is still supported as well.
  4338 
  4339 * 'inductive' and 'datatype': provide projections of mutual rules,
  4340 bundled as foo_bar.inducts;
  4341 
  4342 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  4343 Library.
  4344 
  4345 * Library: moved theory Accessible_Part to main HOL.
  4346 
  4347 * Library: added theory Coinductive_List of potentially infinite lists
  4348 as greatest fixed-point.
  4349 
  4350 * Library: added theory AssocList which implements (finite) maps as
  4351 association lists.
  4352 
  4353 * Method "evaluation" solves goals (i.e. a boolean expression)
  4354 efficiently by compiling it to ML.  The goal is "proved" (via an
  4355 oracle) if it evaluates to True.
  4356 
  4357 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  4358 also when invoked by the simplifier.  This results in the Simplifier
  4359 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  4360 Configuration option fast_arith_split_limit=0 recovers the old
  4361 behavior.
  4362 
  4363 * Support for hex (0x20) and binary (0b1001) numerals.
  4364 
  4365 * New method: reify eqs (t), where eqs are equations for an
  4366 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  4367 parameter, computes a term s::'b and a list xs::'a list and proves the
  4368 theorem I xs s = t. This is also known as reification or quoting. The
  4369 resulting theorem is applied to the subgoal to substitute t with I xs
  4370 s.  If t is omitted, the subgoal itself is reified.
  4371 
  4372 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  4373 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  4374 where f is supposed to be a computable function (in the sense of code
  4375 generattion). The method uses reify to compute s and xs as above then
  4376 applies corr_thm and uses normalization by evaluation to "prove" f s =
  4377 r and finally gets the theorem t = r, which is again applied to the
  4378 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  4379 
  4380 * Reflection: Automatic reification now handels binding, an example is
  4381 available in src/HOL/ex/ReflectionEx.thy
  4382 
  4383 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  4384 command 'statespace' that is similar to 'record', but introduces an
  4385 abstract specification based on the locale infrastructure instead of
  4386 HOL types.  This leads to extra flexibility in composing state spaces,
  4387 in particular multiple inheritance and renaming of components.
  4388 
  4389 
  4390 *** HOL-Complex ***
  4391 
  4392 * Hyperreal: Functions root and sqrt are now defined on negative real
  4393 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  4394 Nonnegativity side conditions have been removed from many lemmas, so
  4395 that more subgoals may now be solved by simplification; potential
  4396 INCOMPATIBILITY.
  4397 
  4398 * Real: new type classes formalize real normed vector spaces and
  4399 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  4400 and norm :: 'a => real.
  4401 
  4402 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  4403 reals into other types. The overloaded constant Reals :: 'a set is now
  4404 defined as range of_real; potential INCOMPATIBILITY.
  4405 
  4406 * Real: proper support for ML code generation, including 'quickcheck'.
  4407 Reals are implemented as arbitrary precision rationals.
  4408 
  4409 * Hyperreal: Several constants that previously worked only for the
  4410 reals have been generalized, so they now work over arbitrary vector
  4411 spaces. Type annotations may need to be added in some cases; potential
  4412 INCOMPATIBILITY.
  4413 
  4414   Infinitesimal  :: ('a::real_normed_vector) star set
  4415   HFinite        :: ('a::real_normed_vector) star set
  4416   HInfinite      :: ('a::real_normed_vector) star set
  4417   approx         :: ('a::real_normed_vector) star => 'a star => bool
  4418   monad          :: ('a::real_normed_vector) star => 'a star set
  4419   galaxy         :: ('a::real_normed_vector) star => 'a star set
  4420   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  4421   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  4422   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  4423   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  4424   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  4425   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  4426   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  4427   sgn            :: 'a::real_normed_vector => 'a
  4428   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  4429 
  4430 * Complex: Some complex-specific constants are now abbreviations for
  4431 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  4432 hnorm.  Other constants have been entirely removed in favor of the
  4433 polymorphic versions (INCOMPATIBILITY):
  4434 
  4435   approx        <-- capprox
  4436   HFinite       <-- CFinite
  4437   HInfinite     <-- CInfinite
  4438   Infinitesimal <-- CInfinitesimal
  4439   monad         <-- cmonad
  4440   galaxy        <-- cgalaxy
  4441   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  4442   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  4443   (ns)deriv     <-- (ns)cderiv
  4444 
  4445 
  4446 *** HOL-Algebra ***
  4447 
  4448 * Formalisation of ideals and the quotient construction over rings.
  4449 
  4450 * Order and lattice theory no longer based on records.
  4451 INCOMPATIBILITY.
  4452 
  4453 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  4454 greatest_closed.  INCOMPATIBILITY.
  4455 
  4456 * Method algebra is now set up via an attribute.  For examples see
  4457 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  4458 of algebraic structures.
  4459 
  4460 * Renamed theory CRing to Ring.
  4461 
  4462 
  4463 *** HOL-Nominal ***
  4464 
  4465 * Substantial, yet incomplete support for nominal datatypes (binding
  4466 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  4467 src/HOL/Nominal/Examples.  Prospective users should consult
  4468 http://isabelle.in.tum.de/nominal/
  4469 
  4470 
  4471 *** ML ***
  4472 
  4473 * ML basics: just one true type int, which coincides with IntInf.int
  4474 (even on SML/NJ).
  4475 
  4476 * ML within Isar: antiquotations allow to embed statically-checked
  4477 formal entities in the source, referring to the context available at
  4478 compile-time.  For example:
  4479 
  4480 ML {* @{sort "{zero,one}"} *}
  4481 ML {* @{typ "'a => 'b"} *}
  4482 ML {* @{term "%x. x"} *}
  4483 ML {* @{prop "x == y"} *}
  4484 ML {* @{ctyp "'a => 'b"} *}
  4485 ML {* @{cterm "%x. x"} *}
  4486 ML {* @{cprop "x == y"} *}
  4487 ML {* @{thm asm_rl} *}
  4488 ML {* @{thms asm_rl} *}
  4489 ML {* @{type_name c} *}
  4490 ML {* @{type_syntax c} *}
  4491 ML {* @{const_name c} *}
  4492 ML {* @{const_syntax c} *}
  4493 ML {* @{context} *}
  4494 ML {* @{theory} *}
  4495 ML {* @{theory Pure} *}
  4496 ML {* @{theory_ref} *}
  4497 ML {* @{theory_ref Pure} *}
  4498 ML {* @{simpset} *}
  4499 ML {* @{claset} *}
  4500 ML {* @{clasimpset} *}
  4501 
  4502 The same works for sources being ``used'' within an Isar context.
  4503 
  4504 * ML in Isar: improved error reporting; extra verbosity with
  4505 ML_Context.trace enabled.
  4506 
  4507 * Pure/General/table.ML: the join operations now works via exceptions
  4508 DUP/SAME instead of type option. This is simpler in simple cases, and
  4509 admits slightly more efficient complex applications.
  4510 
  4511 * Pure: 'advanced' translation functions (parse_translation etc.) now
  4512 use Context.generic instead of just theory.
  4513 
  4514 * Pure: datatype Context.generic joins theory/Proof.context and
  4515 provides some facilities for code that works in either kind of
  4516 context, notably GenericDataFun for uniform theory and proof data.
  4517 
  4518 * Pure: simplified internal attribute type, which is now always
  4519 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  4520 local (Proof.context) attributes have been discontinued, while
  4521 minimizing code duplication. Thm.rule_attribute and
  4522 Thm.declaration_attribute build canonical attributes; see also structure
  4523 Context for further operations on Context.generic, notably
  4524 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  4525 declarations and definitions.
  4526 
  4527 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  4528 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  4529 init only required for impure data. INCOMPATIBILITY: empty really need
  4530 to be empty (no dependencies on theory content!)
  4531 
  4532 * Pure/kernel: consts certification ignores sort constraints given in
  4533 signature declarations. (This information is not relevant to the
  4534 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  4535 potential INCOMPATIBILITY.
  4536 
  4537 * Pure: axiomatic type classes are now purely definitional, with
  4538 explicit proofs of class axioms and super class relations performed
  4539 internally. See Pure/axclass.ML for the main internal interfaces --
  4540 notably AxClass.define_class supercedes AxClass.add_axclass, and
  4541 AxClass.axiomatize_class/classrel/arity supersede
  4542 Sign.add_classes/classrel/arities.
  4543 
  4544 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  4545 global/local versions on theory vs. Proof.context have been
  4546 discontinued; Attrib.syntax and Method.syntax have been adapted
  4547 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  4548 attributes, methods, etc.
  4549 
  4550 * Pure: several functions of signature "... -> theory -> theory * ..."
  4551 have been reoriented to "... -> theory -> ... * theory" in order to
  4552 allow natural usage in combination with the ||>, ||>>, |-> and
  4553 fold_map combinators.
  4554 
  4555 * Pure: official theorem names (closed derivations) and additional
  4556 comments (tags) are now strictly separate.  Name hints -- which are
  4557 maintained as tags -- may be attached any time without affecting the
  4558 derivation.
  4559 
  4560 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  4561 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  4562 achieve the old behaviour.
  4563 
  4564 * Pure: the "Goal" constant is now called "prop", supporting a
  4565 slightly more general idea of ``protecting'' meta-level rule
  4566 statements.
  4567 
  4568 * Pure: Logic.(un)varify only works in a global context, which is now
  4569 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  4570 Logic.legacy_(un)varify as temporary workaround.
  4571 
  4572 * Pure: structure Name provides scalable operations for generating
  4573 internal variable names, notably Name.variants etc.  This replaces
  4574 some popular functions from term.ML:
  4575 
  4576   Term.variant		->  Name.variant
  4577   Term.variantlist	->  Name.variant_list
  4578   Term.invent_names	->  Name.invent_list
  4579 
  4580 Note that low-level renaming rarely occurs in new code -- operations
  4581 from structure Variable are used instead (see below).
  4582 
  4583 * Pure: structure Variable provides fundamental operations for proper
  4584 treatment of fixed/schematic variables in a context.  For example,
  4585 Variable.import introduces fixes for schematics of given facts and
  4586 Variable.export reverses the effect (up to renaming) -- this replaces
  4587 various freeze_thaw operations.
  4588 
  4589 * Pure: structure Goal provides simple interfaces for
  4590 init/conclude/finish and tactical prove operations (replacing former
  4591 Tactic.prove).  Goal.prove is the canonical way to prove results
  4592 within a given context; Goal.prove_global is a degraded version for
  4593 theory level goals, including a global Drule.standard.  Note that
  4594 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  4595 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  4596 in a locale context).
  4597 
  4598 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  4599 and type checking (Syntax.check_term etc.), with common combinations
  4600 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  4601 which are considered legacy and await removal.
  4602 
  4603 * Pure/Syntax: generic interfaces for type unchecking
  4604 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  4605 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  4606 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  4607 available for convenience, but refer to the very same operations using
  4608 a mere theory instead of a full context.
  4609 
  4610 * Isar: simplified treatment of user-level errors, using exception
  4611 ERROR of string uniformly.  Function error now merely raises ERROR,
  4612 without any side effect on output channels.  The Isar toplevel takes
  4613 care of proper display of ERROR exceptions.  ML code may use plain
  4614 handle/can/try; cat_error may be used to concatenate errors like this:
  4615 
  4616   ... handle ERROR msg => cat_error msg "..."
  4617 
  4618 Toplevel ML code (run directly or through the Isar toplevel) may be
  4619 embedded into the Isar toplevel with exception display/debug like
  4620 this:
  4621 
  4622   Isar.toplevel (fn () => ...)
  4623 
  4624 INCOMPATIBILITY, removed special transform_error facilities, removed
  4625 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  4626 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  4627 -- use plain ERROR instead.
  4628 
  4629 * Isar: theory setup now has type (theory -> theory), instead of a
  4630 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  4631 
  4632 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  4633 ProofContext.debug/verbose flags.
  4634 
  4635 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  4636 theory before entering a proof state.  Transactions now always see a
  4637 quasi-functional intermediate checkpoint, both in interactive and
  4638 batch mode.
  4639 
  4640 * Isar: simplified interfaces for outer syntax.  Renamed
  4641 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  4642 OuterSyntax.add_parsers -- this functionality is now included in
  4643 OuterSyntax.command etc.  INCOMPATIBILITY.
  4644 
  4645 * Simplifier: the simpset of a running simplification process now
  4646 contains a proof context (cf. Simplifier.the_context), which is the
  4647 very context that the initial simpset has been retrieved from (by
  4648 simpset_of/local_simpset_of).  Consequently, all plug-in components
  4649 (solver, looper etc.) may depend on arbitrary proof data.
  4650 
  4651 * Simplifier.inherit_context inherits the proof context (plus the
  4652 local bounds) of the current simplification process; any simproc
  4653 etc. that calls the Simplifier recursively should do this!  Removed
  4654 former Simplifier.inherit_bounds, which is already included here --
  4655 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  4656 specify an explicit context using Simplifier.context/theory_context.
  4657 
  4658 * Simplifier/Classical Reasoner: more abstract interfaces
  4659 change_simpset/claset for modifying the simpset/claset reference of a
  4660 theory; raw versions simpset/claset_ref etc. have been discontinued --
  4661 INCOMPATIBILITY.
  4662 
  4663 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  4664 "Trueprop" etc.
  4665 
  4666 
  4667 *** System ***
  4668 
  4669 * settings: the default heap location within ISABELLE_HOME_USER now
  4670 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  4671 Isabelle installations.
  4672 
  4673 * isabelle-process: option -S (secure mode) disables some critical
  4674 operations, notably runtime compilation and evaluation of ML source
  4675 code.
  4676 
  4677 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  4678 
  4679 * Support for parallel execution, using native multicore support of
  4680 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  4681 independent theories, according to the given theory header
  4682 specifications. The maximum number of worker threads is specified via
  4683 usedir option -M or the "max-threads" setting in Proof General. A
  4684 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  4685 to 6 on a 8-core machine.  User-code needs to observe certain
  4686 guidelines for thread-safe programming, see appendix A in the Isar
  4687 Implementation manual.
  4688 
  4689 
  4690 
  4691 New in Isabelle2005 (October 2005)
  4692 ----------------------------------
  4693 
  4694 *** General ***
  4695 
  4696 * Theory headers: the new header syntax for Isar theories is
  4697 
  4698   theory <name>
  4699   imports <theory1> ... <theoryN>
  4700   uses <file1> ... <fileM>
  4701   begin
  4702 
  4703 where the 'uses' part is optional.  The previous syntax
  4704 
  4705   theory <name> = <theory1> + ... + <theoryN>:
  4706 
  4707 will disappear in the next release.  Use isatool fixheaders to convert
  4708 existing theory files.  Note that there is no change in ancient
  4709 non-Isar theories now, but these will disappear soon.
  4710 
  4711 * Theory loader: parent theories can now also be referred to via
  4712 relative and absolute paths.
  4713 
  4714 * Command 'find_theorems' searches for a list of criteria instead of a
  4715 list of constants. Known criteria are: intro, elim, dest, name:string,
  4716 simp:term, and any term. Criteria can be preceded by '-' to select
  4717 theorems that do not match. Intro, elim, dest select theorems that
  4718 match the current goal, name:s selects theorems whose fully qualified
  4719 name contain s, and simp:term selects all simplification rules whose
  4720 lhs match term.  Any other term is interpreted as pattern and selects
  4721 all theorems matching the pattern. Available in ProofGeneral under
  4722 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  4723 
  4724   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  4725 
  4726 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  4727 matching the current goal as introduction rule and not having "HOL."
  4728 in their name (i.e. not being defined in theory HOL).
  4729 
  4730 * Command 'thms_containing' has been discontinued in favour of
  4731 'find_theorems'; INCOMPATIBILITY.
  4732 
  4733 * Communication with Proof General is now 8bit clean, which means that
  4734 Unicode text in UTF-8 encoding may be used within theory texts (both
  4735 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4736 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4737 
  4738   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4739   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4740 
  4741 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4742 Classical Reasoner.  Typical big applications run around 2 times
  4743 faster.
  4744 
  4745 
  4746 *** Document preparation ***
  4747 
  4748 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4749 of raw sources.  Only those symbols that do not require additional
  4750 LaTeX packages (depending on comments in isabellesym.sty) are
  4751 displayed properly, everything else is left verbatim.  isatool display
  4752 and isatool print are used as front ends (these are subject to the
  4753 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4754 
  4755 * Command tags control specific markup of certain regions of text,
  4756 notably folding and hiding.  Predefined tags include "theory" (for
  4757 theory begin and end), "proof" for proof commands, and "ML" for
  4758 commands involving ML code; the additional tags "visible" and
  4759 "invisible" are unused by default.  Users may give explicit tag
  4760 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4761 interpretation of tags is determined by the LaTeX job during document
  4762 preparation: see option -V of isatool usedir, or options -n and -t of
  4763 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4764 \isadroptag.
  4765 
  4766 Several document versions may be produced at the same time via isatool
  4767 usedir (the generated index.html will link all of them).  Typical
  4768 specifications include ''-V document=theory,proof,ML'' to present
  4769 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4770 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4771 these parts without any formal replacement text.  The Isabelle site
  4772 default settings produce ''document'' and ''outline'' versions as
  4773 specified above.
  4774 
  4775 * Several new antiquotations:
  4776 
  4777   @{term_type term} prints a term with its type annotated;
  4778 
  4779   @{typeof term} prints the type of a term;
  4780 
  4781   @{const const} is the same as @{term const}, but checks that the
  4782   argument is a known logical constant;
  4783 
  4784   @{term_style style term} and @{thm_style style thm} print a term or
  4785   theorem applying a "style" to it
  4786 
  4787   @{ML text}
  4788 
  4789 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4790 definitions, equations, inequations etc., 'concl' printing only the
  4791 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4792 to print the specified premise.  TermStyle.add_style provides an ML
  4793 interface for introducing further styles.  See also the "LaTeX Sugar"
  4794 document practical applications.  The ML antiquotation prints
  4795 type-checked ML expressions verbatim.
  4796 
  4797 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4798 and 'text' support optional locale specification '(in loc)', which
  4799 specifies the default context for interpreting antiquotations.  For
  4800 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4801 
  4802 * Option 'locale=NAME' of antiquotations specifies an alternative
  4803 context interpreting the subsequent argument.  For example: @{thm
  4804 [locale=lattice] inf_assoc}.
  4805 
  4806 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4807 a proof context.
  4808 
  4809 * Proper output of antiquotations for theory commands involving a
  4810 proof context (such as 'locale' or 'theorem (in loc) ...').
  4811 
  4812 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4813 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4814 
  4815 * isatool usedir: new option -C (default true) controls whether option
  4816 -D should include a copy of the original document directory; -C false
  4817 prevents unwanted effects such as copying of administrative CVS data.
  4818 
  4819 
  4820 *** Pure ***
  4821 
  4822 * Considerably improved version of 'constdefs' command.  Now performs
  4823 automatic type-inference of declared constants; additional support for
  4824 local structure declarations (cf. locales and HOL records), see also
  4825 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4826 sequential dependencies of definitions within a single 'constdefs'
  4827 section; moreover, the declared name needs to be an identifier.  If
  4828 all fails, consider to fall back on 'consts' and 'defs' separately.
  4829 
  4830 * Improved indexed syntax and implicit structures.  First of all,
  4831 indexed syntax provides a notational device for subscripted
  4832 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4833 expressions.  Secondly, in a local context with structure
  4834 declarations, number indexes \<^sub>n or the empty index (default
  4835 number 1) refer to a certain fixed variable implicitly; option
  4836 show_structs controls printing of implicit structures.  Typical
  4837 applications of these concepts involve record types and locales.
  4838 
  4839 * New command 'no_syntax' removes grammar declarations (and
  4840 translations) resulting from the given syntax specification, which is
  4841 interpreted in the same manner as for the 'syntax' command.
  4842 
  4843 * 'Advanced' translation functions (parse_translation etc.) may depend
  4844 on the signature of the theory context being presently used for
  4845 parsing/printing, see also isar-ref manual.
  4846 
  4847 * Improved 'oracle' command provides a type-safe interface to turn an
  4848 ML expression of type theory -> T -> term into a primitive rule of
  4849 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4850 is already included here); see also FOL/ex/IffExample.thy;
  4851 INCOMPATIBILITY.
  4852 
  4853 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4854 before); "cI" is no longer bound, use "c.intro" instead.
  4855 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4856 axclasses vs. locales.
  4857 
  4858 * Improved internal renaming of symbolic identifiers -- attach primes
  4859 instead of base 26 numbers.
  4860 
  4861 * New flag show_question_marks controls printing of leading question
  4862 marks in schematic variable names.
  4863 
  4864 * In schematic variable names, *any* symbol following \<^isub> or
  4865 \<^isup> is now treated as part of the base name.  For example, the
  4866 following works without printing of awkward ".0" indexes:
  4867 
  4868   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4869     by simp
  4870 
  4871 * Inner syntax includes (*(*nested*) comments*).
  4872 
  4873 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4874 annotations as "(00...)".
  4875 
  4876 * Clear separation of logical types and nonterminals, where the latter
  4877 may only occur in 'syntax' specifications or type abbreviations.
  4878 Before that distinction was only partially implemented via type class
  4879 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4880 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4881 exotic syntax specifications may require further adaption
  4882 (e.g. Cube/Cube.thy).
  4883 
  4884 * Removed obsolete type class "logic", use the top sort {} instead.
  4885 Note that non-logical types should be declared as 'nonterminals'
  4886 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4887 specifications.
  4888 
  4889 * Attributes 'induct' and 'cases': type or set names may now be
  4890 locally fixed variables as well.
  4891 
  4892 * Simplifier: can now control the depth to which conditional rewriting
  4893 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4894 Limit.
  4895 
  4896 * Simplifier: simplification procedures may now take the current
  4897 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4898 interface), which is very useful for calling the Simplifier
  4899 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4900 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4901 low-level mk_simproc no longer applies Logic.varify internally, to
  4902 allow for use in a context of fixed variables.
  4903 
  4904 * thin_tac now works even if the assumption being deleted contains !!
  4905 or ==>.  More generally, erule now works even if the major premise of
  4906 the elimination rule contains !! or ==>.
  4907 
  4908 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4909 
  4910 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4911 from Pure, which contains all common declarations already.  Both
  4912 theories are defined via plain Isabelle/Isar .thy files.
  4913 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4914 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4915 use isatool fixcpure to adapt your theory and ML sources.
  4916 
  4917 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4918 selections of theorems in named facts via index ranges.
  4919 
  4920 * 'print_theorems': in theory mode, really print the difference
  4921 wrt. the last state (works for interactive theory development only),
  4922 in proof mode print all local facts (cf. 'print_facts');
  4923 
  4924 * 'hide': option '(open)' hides only base names.
  4925 
  4926 * More efficient treatment of intermediate checkpoints in interactive
  4927 theory development.
  4928 
  4929 * Code generator is now invoked via code_module (incremental code
  4930 generation) and code_library (modular code generation, ML structures
  4931 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4932 must be quoted when used as identifiers.
  4933 
  4934 * New 'value' command for reading, evaluating and printing terms using
  4935 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4936 quoted when used as identifier.
  4937 
  4938 
  4939 *** Locales ***
  4940 
  4941 * New commands for the interpretation of locale expressions in
  4942 theories (1), locales (2) and proof contexts (3).  These generate
  4943 proof obligations from the expression specification.  After the
  4944 obligations have been discharged, theorems of the expression are added
  4945 to the theory, target locale or proof context.  The synopsis of the
  4946 commands is a follows:
  4947 
  4948   (1) interpretation expr inst
  4949   (2) interpretation target < expr
  4950   (3) interpret expr inst
  4951 
  4952 Interpretation in theories and proof contexts require a parameter
  4953 instantiation of terms from the current context.  This is applied to
  4954 specifications and theorems of the interpreted expression.
  4955 Interpretation in locales only permits parameter renaming through the
  4956 locale expression.  Interpretation is smart in that interpretations
  4957 that are active already do not occur in proof obligations, neither are
  4958 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4959 inspect active interpretations of a particular locale.  For details,
  4960 see the Isar Reference manual.  Examples can be found in
  4961 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4962 
  4963 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4964 'interpret' instead.
  4965 
  4966 * New context element 'constrains' for adding type constraints to
  4967 parameters.
  4968 
  4969 * Context expressions: renaming of parameters with syntax
  4970 redeclaration.
  4971 
  4972 * Locale declaration: 'includes' disallowed.
  4973 
  4974 * Proper static binding of attribute syntax -- i.e. types / terms /
  4975 facts mentioned as arguments are always those of the locale definition
  4976 context, independently of the context of later invocations.  Moreover,
  4977 locale operations (renaming and type / term instantiation) are applied
  4978 to attribute arguments as expected.
  4979 
  4980 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4981 actual attributes; rare situations may require Attrib.attribute to
  4982 embed those attributes into Attrib.src that lack concrete syntax.
  4983 Attribute implementations need to cooperate properly with the static
  4984 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4985 Attrib.XXX_thm etc. already do the right thing without further
  4986 intervention.  Only unusual applications -- such as "where" or "of"
  4987 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4988 on the context and the facts involved -- may have to assign parsed
  4989 values to argument tokens explicitly.
  4990 
  4991 * Changed parameter management in theorem generation for long goal
  4992 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4993 theorem statement in rare situations.
  4994 
  4995 * Locale inspection command 'print_locale' omits notes elements.  Use
  4996 'print_locale!' to have them included in the output.
  4997 
  4998 
  4999 *** Provers ***
  5000 
  5001 * Provers/hypsubst.ML: improved version of the subst method, for
  5002 single-step rewriting: it now works in bound variable contexts. New is
  5003 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  5004 rewrite a different subterm than the original subst method, which is
  5005 still available as 'simplesubst'.
  5006 
  5007 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  5008 and quasi orders.
  5009 
  5010 * Provers/trancl.ML: new transitivity reasoner for transitive and
  5011 reflexive-transitive closure of relations.
  5012 
  5013 * Provers/blast.ML: new reference depth_limit to make blast's depth
  5014 limit (previously hard-coded with a value of 20) user-definable.
  5015 
  5016 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  5017 is peformed already.  Object-logics merely need to finish their
  5018 initial simpset configuration as before.  INCOMPATIBILITY.
  5019 
  5020 
  5021 *** HOL ***
  5022 
  5023 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  5024 
  5025   syntax (epsilon)
  5026     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  5027 
  5028 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  5029 and x-symbol; use option '-m epsilon' to get it actually printed.
  5030 Moreover, the mathematically important symbolic identifier \<epsilon>
  5031 becomes available as variable, constant etc.  INCOMPATIBILITY,
  5032 
  5033 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  5034 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  5035 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  5036 support corresponding Isar calculations.
  5037 
  5038 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  5039 instead of ":".
  5040 
  5041 * theory SetInterval: changed the syntax for open intervals:
  5042 
  5043   Old       New
  5044   {..n(}    {..<n}
  5045   {)n..}    {n<..}
  5046   {m..n(}   {m..<n}
  5047   {)m..n}   {m<..n}
  5048   {)m..n(}  {m<..<n}
  5049 
  5050 The old syntax is still supported but will disappear in the next
  5051 release.  For conversion use the following Emacs search and replace
  5052 patterns (these are not perfect but work quite well):
  5053 
  5054   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  5055   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  5056 
  5057 * Theory Commutative_Ring (in Library): method comm_ring for proving
  5058 equalities in commutative rings; method 'algebra' provides a generic
  5059 interface.
  5060 
  5061 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  5062 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  5063 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  5064 be a tuple pattern.
  5065 
  5066 Some new syntax forms are available:
  5067 
  5068   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  5069   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  5070   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  5071   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  5072 
  5073 The latter form "\<Sum>x < k. e" used to be based on a separate
  5074 function "Summation", which has been discontinued.
  5075 
  5076 * theory Finite_Set: in structured induction proofs, the insert case
  5077 is now 'case (insert x F)' instead of the old counterintuitive 'case
  5078 (insert F x)'.
  5079 
  5080 * The 'refute' command has been extended to support a much larger
  5081 fragment of HOL, including axiomatic type classes, constdefs and
  5082 typedefs, inductive datatypes and recursion.
  5083 
  5084 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  5085 Requires zChaff with proof generation to be installed.  See
  5086 HOL/ex/SAT_Examples.thy for examples.
  5087 
  5088 * Datatype induction via method 'induct' now preserves the name of the
  5089 induction variable. For example, when proving P(xs::'a list) by
  5090 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  5091 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  5092 in unstructured proof scripts.
  5093 
  5094 * Reworked implementation of records.  Improved scalability for
  5095 records with many fields, avoiding performance problems for type
  5096 inference. Records are no longer composed of nested field types, but
  5097 of nested extension types. Therefore the record type only grows linear
  5098 in the number of extensions and not in the number of fields.  The
  5099 top-level (users) view on records is preserved.  Potential
  5100 INCOMPATIBILITY only in strange cases, where the theory depends on the
  5101 old record representation. The type generated for a record is called
  5102 <record_name>_ext_type.
  5103 
  5104 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  5105 proofs triggered by a record definition or a simproc (if
  5106 quick_and_dirty is enabled).  Definitions of large records can take
  5107 quite long.
  5108 
  5109 New simproc record_upd_simproc for simplification of multiple record
  5110 updates enabled by default.  Moreover, trivial updates are also
  5111 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  5112 occasionally, since simplification is more powerful by default.
  5113 
  5114 * typedef: proper support for polymorphic sets, which contain extra
  5115 type-variables in the term.
  5116 
  5117 * Simplifier: automatically reasons about transitivity chains
  5118 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  5119 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  5120 old proofs break occasionally as simplification may now solve more
  5121 goals than previously.
  5122 
  5123 * Simplifier: converts x <= y into x = y if assumption y <= x is
  5124 present.  Works for all partial orders (class "order"), in particular
  5125 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  5126 just like y <= x.
  5127 
  5128 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  5129 bound variable or a constant then the let is unfolded.  Otherwise
  5130 first a is simplified to b, and then f b is simplified to g. If
  5131 possible we abstract b from g arriving at "let x = b in h x",
  5132 otherwise we unfold the let and arrive at g.  The simproc can be
  5133 enabled/disabled by the reference use_let_simproc.  Potential
  5134 INCOMPATIBILITY since simplification is more powerful by default.
  5135 
  5136 * Classical reasoning: the meson method now accepts theorems as arguments.
  5137 
  5138 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  5139 jobs to provide advice on the provability of subgoals.
  5140 
  5141 * Theory OrderedGroup and Ring_and_Field: various additions and
  5142 improvements to faciliate calculations involving equalities and
  5143 inequalities.
  5144 
  5145 The following theorems have been eliminated or modified
  5146 (INCOMPATIBILITY):
  5147 
  5148   abs_eq             now named abs_of_nonneg
  5149   abs_of_ge_0        now named abs_of_nonneg
  5150   abs_minus_eq       now named abs_of_nonpos
  5151   imp_abs_id         now named abs_of_nonneg
  5152   imp_abs_neg_id     now named abs_of_nonpos
  5153   mult_pos           now named mult_pos_pos
  5154   mult_pos_le        now named mult_nonneg_nonneg
  5155   mult_pos_neg_le    now named mult_nonneg_nonpos
  5156   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  5157   mult_neg           now named mult_neg_neg
  5158   mult_neg_le        now named mult_nonpos_nonpos
  5159 
  5160 * The following lemmas in Ring_and_Field have been added to the simplifier:
  5161      
  5162      zero_le_square
  5163      not_square_less_zero 
  5164 
  5165   The following lemmas have been deleted from Real/RealPow:
  5166   
  5167      realpow_zero_zero
  5168      realpow_two
  5169      realpow_less
  5170      zero_le_power
  5171      realpow_two_le
  5172      abs_realpow_two
  5173      realpow_two_abs     
  5174 
  5175 * Theory Parity: added rules for simplifying exponents.
  5176 
  5177 * Theory List:
  5178 
  5179 The following theorems have been eliminated or modified
  5180 (INCOMPATIBILITY):
  5181 
  5182   list_all_Nil       now named list_all.simps(1)
  5183   list_all_Cons      now named list_all.simps(2)
  5184   list_all_conv      now named list_all_iff
  5185   set_mem_eq         now named mem_iff
  5186 
  5187 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  5188 asymptotic "big O" calculations.  See the notes in BigO.thy.
  5189 
  5190 
  5191 *** HOL-Complex ***
  5192 
  5193 * Theory RealDef: better support for embedding natural numbers and
  5194 integers in the reals.
  5195 
  5196 The following theorems have been eliminated or modified
  5197 (INCOMPATIBILITY):
  5198 
  5199   exp_ge_add_one_self  now requires no hypotheses
  5200   real_of_int_add      reversed direction of equality (use [symmetric])
  5201   real_of_int_minus    reversed direction of equality (use [symmetric])
  5202   real_of_int_diff     reversed direction of equality (use [symmetric])
  5203   real_of_int_mult     reversed direction of equality (use [symmetric])
  5204 
  5205 * Theory RComplete: expanded support for floor and ceiling functions.
  5206 
  5207 * Theory Ln is new, with properties of the natural logarithm
  5208 
  5209 * Hyperreal: There is a new type constructor "star" for making
  5210 nonstandard types.  The old type names are now type synonyms:
  5211 
  5212   hypreal = real star
  5213   hypnat = nat star
  5214   hcomplex = complex star
  5215 
  5216 * Hyperreal: Many groups of similarly-defined constants have been
  5217 replaced by polymorphic versions (INCOMPATIBILITY):
  5218 
  5219   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  5220 
  5221   starset      <-- starsetNat, starsetC
  5222   *s*          <-- *sNat*, *sc*
  5223   starset_n    <-- starsetNat_n, starsetC_n
  5224   *sn*         <-- *sNatn*, *scn*
  5225   InternalSets <-- InternalNatSets, InternalCSets
  5226 
  5227   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  5228   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  5229   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  5230   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  5231   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  5232 
  5233 * Hyperreal: Many type-specific theorems have been removed in favor of
  5234 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  5235 
  5236   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  5237   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  5238   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  5239   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  5240   right_minus <-- hypreal_add_minus
  5241   left_minus <-- {hypreal,hcomplex}_add_minus_left
  5242   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  5243   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  5244   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  5245   mult_1_right <-- hcomplex_mult_one_right
  5246   mult_zero_left <-- hcomplex_mult_zero_left
  5247   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  5248   right_distrib <-- hypnat_add_mult_distrib2
  5249   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  5250   right_inverse <-- hypreal_mult_inverse
  5251   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  5252   order_refl <-- {hypreal,hypnat}_le_refl
  5253   order_trans <-- {hypreal,hypnat}_le_trans
  5254   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  5255   order_less_le <-- {hypreal,hypnat}_less_le
  5256   linorder_linear <-- {hypreal,hypnat}_le_linear
  5257   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  5258   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  5259   add_nonneg_nonneg <-- hypreal_le_add_order
  5260 
  5261 * Hyperreal: Separate theorems having to do with type-specific
  5262 versions of constants have been merged into theorems that apply to the
  5263 new polymorphic constants (INCOMPATIBILITY):
  5264 
  5265   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  5266   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  5267   STAR_Un <-- {STAR,NatStar,STARC}_Un
  5268   STAR_Int <-- {STAR,NatStar,STARC}_Int
  5269   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  5270   STAR_subset <-- {STAR,NatStar,STARC}_subset
  5271   STAR_mem <-- {STAR,NatStar,STARC}_mem
  5272   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  5273   STAR_diff <-- {STAR,STARC}_diff
  5274   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  5275     STARC_hcomplex_of_complex}_image_subset
  5276   starset_n_Un <-- starset{Nat,C}_n_Un
  5277   starset_n_Int <-- starset{Nat,C}_n_Int
  5278   starset_n_Compl <-- starset{Nat,C}_n_Compl
  5279   starset_n_diff <-- starset{Nat,C}_n_diff
  5280   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  5281   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  5282   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  5283   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  5284   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  5285   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  5286   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  5287   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  5288   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  5289   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  5290   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  5291   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  5292   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  5293   starfun_diff <-- starfun{C,RC,CR}_diff
  5294   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  5295   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  5296   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  5297   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  5298   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  5299   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  5300   starfun_Id <-- starfunC_Id
  5301   starfun_approx <-- starfun{Nat,CR}_approx
  5302   starfun_capprox <-- starfun{C,RC}_capprox
  5303   starfun_abs <-- starfunNat_rabs
  5304   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  5305   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  5306   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  5307   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  5308   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  5309   starfun_add_approx <-- starfunCR_add_approx
  5310   starfun_inverse_inverse <-- starfunC_inverse_inverse
  5311   starfun_divide <-- starfun{C,CR,RC}_divide
  5312   starfun_n <-- starfun{Nat,C}_n
  5313   starfun_n_mult <-- starfun{Nat,C}_n_mult
  5314   starfun_n_add <-- starfun{Nat,C}_n_add
  5315   starfun_n_add_minus <-- starfunNat_n_add_minus
  5316   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  5317   starfun_n_minus <-- starfun{Nat,C}_n_minus
  5318   starfun_n_eq <-- starfun{Nat,C}_n_eq
  5319 
  5320   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  5321   star_n_minus <-- {hypreal,hcomplex}_minus
  5322   star_n_diff <-- {hypreal,hcomplex}_diff
  5323   star_n_mult <-- {hypreal,hcomplex}_mult
  5324   star_n_inverse <-- {hypreal,hcomplex}_inverse
  5325   star_n_le <-- {hypreal,hypnat}_le
  5326   star_n_less <-- {hypreal,hypnat}_less
  5327   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  5328   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  5329   star_n_abs <-- hypreal_hrabs
  5330   star_n_divide <-- hcomplex_divide
  5331 
  5332   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  5333   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  5334   star_of_diff <-- hypreal_of_real_diff
  5335   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  5336   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  5337   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  5338   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  5339   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  5340   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  5341   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  5342   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  5343   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  5344   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  5345   star_of_number_of <-- {hypreal,hcomplex}_number_of
  5346   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  5347   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  5348   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  5349   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  5350   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  5351   star_of_power <-- hypreal_of_real_power
  5352   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  5353 
  5354 * Hyperreal: new method "transfer" that implements the transfer
  5355 principle of nonstandard analysis. With a subgoal that mentions
  5356 nonstandard types like "'a star", the command "apply transfer"
  5357 replaces it with an equivalent one that mentions only standard types.
  5358 To be successful, all free variables must have standard types; non-
  5359 standard variables must have explicit universal quantifiers.
  5360 
  5361 * Hyperreal: A theory of Taylor series.
  5362 
  5363 
  5364 *** HOLCF ***
  5365 
  5366 * Discontinued special version of 'constdefs' (which used to support
  5367 continuous functions) in favor of the general Pure one with full
  5368 type-inference.
  5369 
  5370 * New simplification procedure for solving continuity conditions; it
  5371 is much faster on terms with many nested lambda abstractions (cubic
  5372 instead of exponential time).
  5373 
  5374 * New syntax for domain package: selector names are now optional.
  5375 Parentheses should be omitted unless argument is lazy, for example:
  5376 
  5377   domain 'a stream = cons "'a" (lazy "'a stream")
  5378 
  5379 * New command 'fixrec' for defining recursive functions with pattern
  5380 matching; defining multiple functions with mutual recursion is also
  5381 supported.  Patterns may include the constants cpair, spair, up, sinl,
  5382 sinr, or any data constructor defined by the domain package. The given
  5383 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  5384 syntax and examples.
  5385 
  5386 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  5387 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  5388 but the proof obligation additionally includes an admissibility
  5389 requirement. The packages generate instances of class cpo or pcpo,
  5390 with continuity and strictness theorems for Rep and Abs.
  5391 
  5392 * HOLCF: Many theorems have been renamed according to a more standard naming
  5393 scheme (INCOMPATIBILITY):
  5394 
  5395   foo_inject:  "foo$x = foo$y ==> x = y"
  5396   foo_eq:      "(foo$x = foo$y) = (x = y)"
  5397   foo_less:    "(foo$x << foo$y) = (x << y)"
  5398   foo_strict:  "foo$UU = UU"
  5399   foo_defined: "... ==> foo$x ~= UU"
  5400   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  5401 
  5402 
  5403 *** ZF ***
  5404 
  5405 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  5406 including the First Isomorphism Theorem (on quotienting by the kernel
  5407 of a homomorphism).
  5408 
  5409 * ZF/Simplifier: install second copy of type solver that actually
  5410 makes use of TC rules declared to Isar proof contexts (or locales);
  5411 the old version is still required for ML proof scripts.
  5412 
  5413 
  5414 *** Cube ***
  5415 
  5416 * Converted to Isar theory format; use locales instead of axiomatic
  5417 theories.
  5418 
  5419 
  5420 *** ML ***
  5421 
  5422 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  5423 for ||>, ||>>, |>>,
  5424 
  5425 * Pure/library.ML no longer defines its own option datatype, but uses
  5426 that of the SML basis, which has constructors NONE and SOME instead of
  5427 None and Some, as well as exception Option.Option instead of OPTION.
  5428 The functions the, if_none, is_some, is_none have been adapted
  5429 accordingly, while Option.map replaces apsome.
  5430 
  5431 * Pure/library.ML: the exception LIST has been given up in favour of
  5432 the standard exceptions Empty and Subscript, as well as
  5433 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  5434 superceded by the standard hd and tl functions etc.
  5435 
  5436 A number of basic list functions are no longer exported to the ML
  5437 toplevel, as they are variants of predefined functions.  The following
  5438 suggests how one can translate existing code:
  5439 
  5440     rev_append xs ys = List.revAppend (xs, ys)
  5441     nth_elem (i, xs) = List.nth (xs, i)
  5442     last_elem xs = List.last xs
  5443     flat xss = List.concat xss
  5444     seq fs = List.app fs
  5445     partition P xs = List.partition P xs
  5446     mapfilter f xs = List.mapPartial f xs
  5447 
  5448 * Pure/library.ML: several combinators for linear functional
  5449 transformations, notably reverse application and composition:
  5450 
  5451   x |> f                f #> g
  5452   (x, y) |-> f          f #-> g
  5453 
  5454 * Pure/library.ML: introduced/changed precedence of infix operators:
  5455 
  5456   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  5457   infix 2 ?;
  5458   infix 3 o oo ooo oooo;
  5459   infix 4 ~~ upto downto;
  5460 
  5461 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  5462 infix operators.
  5463 
  5464 * Pure/library.ML: natural list combinators fold, fold_rev, and
  5465 fold_map support linear functional transformations and nesting.  For
  5466 example:
  5467 
  5468   fold f [x1, ..., xN] y =
  5469     y |> f x1 |> ... |> f xN
  5470 
  5471   (fold o fold) f [xs1, ..., xsN] y =
  5472     y |> fold f xs1 |> ... |> fold f xsN
  5473 
  5474   fold f [x1, ..., xN] =
  5475     f x1 #> ... #> f xN
  5476 
  5477   (fold o fold) f [xs1, ..., xsN] =
  5478     fold f xs1 #> ... #> fold f xsN
  5479 
  5480 * Pure/library.ML: the following selectors on type 'a option are
  5481 available:
  5482 
  5483   the:               'a option -> 'a  (*partial*)
  5484   these:             'a option -> 'a  where 'a = 'b list
  5485   the_default: 'a -> 'a option -> 'a
  5486   the_list:          'a option -> 'a list
  5487 
  5488 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5489 basic operations for association lists, following natural argument
  5490 order; moreover the explicit equality predicate passed here avoids
  5491 potentially expensive polymorphic runtime equality checks.
  5492 The old functions may be expressed as follows:
  5493 
  5494   assoc = uncurry (AList.lookup (op =))
  5495   assocs = these oo AList.lookup (op =)
  5496   overwrite = uncurry (AList.update (op =)) o swap
  5497 
  5498 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5499 
  5500   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  5501   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  5502 
  5503 replacing make_keylist and keyfilter (occassionally used)
  5504 Naive rewrites:
  5505 
  5506   make_keylist = AList.make
  5507   keyfilter = AList.find (op =)
  5508 
  5509 * eq_fst and eq_snd now take explicit equality parameter, thus
  5510   avoiding eqtypes. Naive rewrites:
  5511 
  5512     eq_fst = eq_fst (op =)
  5513     eq_snd = eq_snd (op =)
  5514 
  5515 * Removed deprecated apl and apr (rarely used).
  5516   Naive rewrites:
  5517 
  5518     apl (n, op) =>>= curry op n
  5519     apr (op, m) =>>= fn n => op (n, m)
  5520 
  5521 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  5522 provides a reasonably efficient light-weight implementation of sets as
  5523 lists.
  5524 
  5525 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  5526 few new operations; existing lookup and update are now curried to
  5527 follow natural argument order (for use with fold etc.);
  5528 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  5529 
  5530 * Pure/General: output via the Isabelle channels of
  5531 writeln/warning/error etc. is now passed through Output.output, with a
  5532 hook for arbitrary transformations depending on the print_mode
  5533 (cf. Output.add_mode -- the first active mode that provides a output
  5534 function wins).  Already formatted output may be embedded into further
  5535 text via Output.raw; the result of Pretty.string_of/str_of and derived
  5536 functions (string_of_term/cterm/thm etc.) is already marked raw to
  5537 accommodate easy composition of diagnostic messages etc.  Programmers
  5538 rarely need to care about Output.output or Output.raw at all, with
  5539 some notable exceptions: Output.output is required when bypassing the
  5540 standard channels (writeln etc.), or in token translations to produce
  5541 properly formatted results; Output.raw is required when capturing
  5542 already output material that will eventually be presented to the user
  5543 a second time.  For the default print mode, both Output.output and
  5544 Output.raw have no effect.
  5545 
  5546 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  5547 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  5548 cumulative results are displayed at the end of a batch session.
  5549 
  5550 * Pure/General: File.sysify_path and File.quote_sysify path have been
  5551 replaced by File.platform_path and File.shell_path (with appropriate
  5552 hooks).  This provides a clean interface for unusual systems where the
  5553 internal and external process view of file names are different.
  5554 
  5555 * Pure: more efficient orders for basic syntactic entities: added
  5556 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  5557 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  5558 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  5559 orders now -- potential INCOMPATIBILITY for code that depends on a
  5560 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  5561 Library.sort_strings on result).
  5562 
  5563 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  5564 fold_types traverse types/terms from left to right, observing natural
  5565 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  5566 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  5567 
  5568 * Pure: name spaces have been refined, with significant changes of the
  5569 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  5570 to extern(_table).  The plain name entry path is superceded by a
  5571 general 'naming' context, which also includes the 'policy' to produce
  5572 a fully qualified name and external accesses of a fully qualified
  5573 name; NameSpace.extend is superceded by context dependent
  5574 Sign.declare_name.  Several theory and proof context operations modify
  5575 the naming context.  Especially note Theory.restore_naming and
  5576 ProofContext.restore_naming to get back to a sane state; note that
  5577 Theory.add_path is no longer sufficient to recover from
  5578 Theory.absolute_path in particular.
  5579 
  5580 * Pure: new flags short_names (default false) and unique_names
  5581 (default true) for controlling output of qualified names.  If
  5582 short_names is set, names are printed unqualified.  If unique_names is
  5583 reset, the name prefix is reduced to the minimum required to achieve
  5584 the original result when interning again, even if there is an overlap
  5585 with earlier declarations.
  5586 
  5587 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  5588 now 'extend', and 'merge' gets an additional Pretty.pp argument
  5589 (useful for printing error messages).  INCOMPATIBILITY.
  5590 
  5591 * Pure: major reorganization of the theory context.  Type Sign.sg and
  5592 Theory.theory are now identified, referring to the universal
  5593 Context.theory (see Pure/context.ML).  Actual signature and theory
  5594 content is managed as theory data.  The old code and interfaces were
  5595 spread over many files and structures; the new arrangement introduces
  5596 considerable INCOMPATIBILITY to gain more clarity:
  5597 
  5598   Context -- theory management operations (name, identity, inclusion,
  5599     parents, ancestors, merge, etc.), plus generic theory data;
  5600 
  5601   Sign -- logical signature and syntax operations (declaring consts,
  5602     types, etc.), plus certify/read for common entities;
  5603 
  5604   Theory -- logical theory operations (stating axioms, definitions,
  5605     oracles), plus a copy of logical signature operations (consts,
  5606     types, etc.); also a few basic management operations (Theory.copy,
  5607     Theory.merge, etc.)
  5608 
  5609 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  5610 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  5611 for convenience -- they merely return the theory.
  5612 
  5613 * Pure: type Type.tsig is superceded by theory in most interfaces.
  5614 
  5615 * Pure: the Isar proof context type is already defined early in Pure
  5616 as Context.proof (note that ProofContext.context and Proof.context are
  5617 aliases, where the latter is the preferred name).  This enables other
  5618 Isabelle components to refer to that type even before Isar is present.
  5619 
  5620 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  5621 typeK, constK, axiomK, oracleK), but provide explicit operations for
  5622 any of these kinds.  For example, Sign.intern typeK is now
  5623 Sign.intern_type, Theory.hide_space Sign.typeK is now
  5624 Theory.hide_types.  Also note that former
  5625 Theory.hide_classes/types/consts are now
  5626 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  5627 internalize their arguments!  INCOMPATIBILITY.
  5628 
  5629 * Pure: get_thm interface (of PureThy and ProofContext) expects
  5630 datatype thmref (with constructors Name and NameSelection) instead of
  5631 plain string -- INCOMPATIBILITY;
  5632 
  5633 * Pure: cases produced by proof methods specify options, where NONE
  5634 means to remove case bindings -- INCOMPATIBILITY in
  5635 (RAW_)METHOD_CASES.
  5636 
  5637 * Pure: the following operations retrieve axioms or theorems from a
  5638 theory node or theory hierarchy, respectively:
  5639 
  5640   Theory.axioms_of: theory -> (string * term) list
  5641   Theory.all_axioms_of: theory -> (string * term) list
  5642   PureThy.thms_of: theory -> (string * thm) list
  5643   PureThy.all_thms_of: theory -> (string * thm) list
  5644 
  5645 * Pure: print_tac now outputs the goal through the trace channel.
  5646 
  5647 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  5648 Reference Toplevel.debug (default false) controls detailed printing
  5649 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  5650 controls execution profiling -- set to 1 for time and 2 for space
  5651 (both increase the runtime).
  5652 
  5653 * Isar session: The initial use of ROOT.ML is now always timed,
  5654 i.e. the log will show the actual process times, in contrast to the
  5655 elapsed wall-clock time that the outer shell wrapper produces.
  5656 
  5657 * Simplifier: improved handling of bound variables (nameless
  5658 representation, avoid allocating new strings).  Simprocs that invoke
  5659 the Simplifier recursively should use Simplifier.inherit_bounds to
  5660 avoid local name clashes.  Failure to do so produces warnings
  5661 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  5662 for further details.
  5663 
  5664 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  5665 bindings for all theorems stored within a given theory; this may help
  5666 in porting non-Isar theories to Isar ones, while keeping ML proof
  5667 scripts for the time being.
  5668 
  5669 * ML operator HTML.with_charset specifies the charset begin used for
  5670 generated HTML files.  For example:
  5671 
  5672   HTML.with_charset "utf-8" use_thy "Hebrew";
  5673   HTML.with_charset "utf-8" use_thy "Chinese";
  5674 
  5675 
  5676 *** System ***
  5677 
  5678 * Allow symlinks to all proper Isabelle executables (Isabelle,
  5679 isabelle, isatool etc.).
  5680 
  5681 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  5682 isatool doc, isatool mkdir, display_drafts etc.).
  5683 
  5684 * isatool usedir: option -f allows specification of the ML file to be
  5685 used by Isabelle; default is ROOT.ML.
  5686 
  5687 * New isatool version outputs the version identifier of the Isabelle
  5688 distribution being used.
  5689 
  5690 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  5691 (containing Boolean satisfiability problems) into Isabelle/HOL
  5692 theories.
  5693 
  5694 
  5695 
  5696 New in Isabelle2004 (April 2004)
  5697 --------------------------------
  5698 
  5699 *** General ***
  5700 
  5701 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  5702   Replaces linorder.ML.
  5703 
  5704 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  5705   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  5706   (\<a>...\<z>), are now considered normal letters, and can therefore
  5707   be used anywhere where an ASCII letter (a...zA...Z) has until
  5708   now. COMPATIBILITY: This obviously changes the parsing of some
  5709   terms, especially where a symbol has been used as a binder, say
  5710   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  5711   as an identifier.  Fix it by inserting a space around former
  5712   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  5713   existing theory and ML files.
  5714 
  5715 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  5716 
  5717 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  5718   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  5719   a normal (but invisible) letter. For multiple letter subscripts repeat
  5720   \<^isub> like this: x\<^isub>1\<^isub>2.
  5721 
  5722 * Pure: There are now sub-/superscripts that can span more than one
  5723   character. Text between \<^bsub> and \<^esub> is set in subscript in
  5724   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  5725   superscript. The new control characters are not identifier parts.
  5726 
  5727 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5728   content of "..." to the latex file instead of \isacntrl... . The "..."
  5729   may consist of any printable characters excluding the end bracket >.
  5730 
  5731 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5732   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5733   declare constants "final", which prevents their being given a definition
  5734   later.  It is useful for constants whose behaviour is fixed axiomatically
  5735   rather than definitionally, such as the meta-logic connectives.
  5736 
  5737 * Pure: 'instance' now handles general arities with general sorts
  5738   (i.e. intersections of classes),
  5739 
  5740 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5741   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5742   It can be changed to alter the colors/layout of generated pages.
  5743 
  5744 
  5745 *** Isar ***
  5746 
  5747 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5748   cut_tac, subgoal_tac and thin_tac:
  5749   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5750     locales are no longer forced to write Isar proof scripts.
  5751     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5752     emulations.
  5753   - INCOMPATIBILITY: names of variables to be instantiated may no
  5754     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5755     This is consistent with the instantiation attribute "where".
  5756 
  5757 * Attributes "where" and "of":
  5758   - Now take type variables of instantiated theorem into account when reading
  5759     the instantiation string.  This fixes a bug that caused instantiated
  5760     theorems to have too special types in some circumstances.
  5761   - "where" permits explicit instantiations of type variables.
  5762 
  5763 * Calculation commands "moreover" and "also" no longer interfere with
  5764   current facts ("this"), admitting arbitrary combinations with "then"
  5765   and derived forms.
  5766 
  5767 * Locales:
  5768   - Goal statements involving the context element "includes" no longer
  5769     generate theorems with internal delta predicates (those ending on
  5770     "_axioms") in the premise.
  5771     Resolve particular premise with <locale>.intro to obtain old form.
  5772   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5773     specification and "includes" elements in goal statement.
  5774   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5775     [intro?] and [elim?] (respectively) by default.
  5776   - Experimental command for instantiation of locales in proof contexts:
  5777         instantiate <label>[<attrs>]: <loc>
  5778     Instantiates locale <loc> and adds all its theorems to the current context
  5779     taking into account their attributes.  Label and attrs are optional
  5780     modifiers, like in theorem declarations.  If present, names of
  5781     instantiated theorems are qualified with <label>, and the attributes
  5782     <attrs> are applied after any attributes these theorems might have already.
  5783       If the locale has assumptions, a chained fact of the form
  5784     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5785     are derived.  The command does not support old-style locales declared
  5786     with "locale (open)".
  5787       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5788 
  5789 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5790   (Isar) contexts.
  5791 
  5792 
  5793 *** HOL ***
  5794 
  5795 * Proof import: new image HOL4 contains the imported library from
  5796   the HOL4 system with about 2500 theorems. It is imported by
  5797   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5798   can be used like any other Isabelle image.  See
  5799   HOL/Import/HOL/README for more information.
  5800 
  5801 * Simplifier:
  5802   - Much improved handling of linear and partial orders.
  5803     Reasoners for linear and partial orders are set up for type classes
  5804     "linorder" and "order" respectively, and are added to the default simpset
  5805     as solvers.  This means that the simplifier can build transitivity chains
  5806     to solve goals from the assumptions.
  5807   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5808     of blast or auto after simplification become unnecessary because the goal
  5809     is solved by simplification already.
  5810 
  5811 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5812     all proved in axiomatic type classes for semirings, rings and fields.
  5813 
  5814 * Numerics:
  5815   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5816     now formalized using the Ring_and_Field theory mentioned above.
  5817   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5818     than before, because now they are set up once in a generic manner.
  5819   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5820     Look for the general versions in Ring_and_Field (and Power if they concern
  5821     exponentiation).
  5822 
  5823 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5824 
  5825 * Records:
  5826   - Record types are now by default printed with their type abbreviation
  5827     instead of the list of all field types. This can be configured via
  5828     the reference "print_record_type_abbr".
  5829   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5830     (not enabled by default).
  5831   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5832     EX x. x = sel r to True (not enabled by default).
  5833   - Tactic "record_split_simp_tac" to split and simplify records added.
  5834 
  5835 * 'specification' command added, allowing for definition by
  5836   specification.  There is also an 'ax_specification' command that
  5837   introduces the new constants axiomatically.
  5838 
  5839 * arith(_tac) is now able to generate counterexamples for reals as well.
  5840 
  5841 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5842 
  5843 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5844   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5845 
  5846 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5847   matrix theory to linear programming.
  5848 
  5849 * Unions and Intersections:
  5850   The latex output syntax of UN and INT has been changed
  5851   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5852   i.e. the index formulae has become a subscript.
  5853   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5854 
  5855 * Unions and Intersections over Intervals:
  5856   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5857   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5858   like in normal math, and corresponding versions for < and for intersection.
  5859 
  5860 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5861   lexicographic dictonary ordering has been added as "lexord".
  5862 
  5863 * ML: the legacy theory structures Int and List have been removed. They had
  5864   conflicted with ML Basis Library structures having the same names.
  5865 
  5866 * 'refute' command added to search for (finite) countermodels.  Only works
  5867   for a fragment of HOL.  The installation of an external SAT solver is
  5868   highly recommended.  See "HOL/Refute.thy" for details.
  5869 
  5870 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5871   formulae under an assignment of free variables to random values.
  5872   In contrast to 'refute', it can deal with inductive datatypes,
  5873   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5874   for examples.
  5875 
  5876 
  5877 *** HOLCF ***
  5878 
  5879 * Streams now come with concatenation and are part of the HOLCF image
  5880 
  5881 
  5882 
  5883 New in Isabelle2003 (May 2003)
  5884 ------------------------------
  5885 
  5886 *** General ***
  5887 
  5888 * Provers/simplifier:
  5889 
  5890   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5891     Assumptions are now subject to complete mutual simplification,
  5892     not just from left to right. The simplifier now preserves
  5893     the order of assumptions.
  5894 
  5895     Potential INCOMPATIBILITY:
  5896 
  5897     -- simp sometimes diverges where the old version did
  5898        not, e.g. invoking simp on the goal
  5899 
  5900         [| P (f x); y = x; f x = f y |] ==> Q
  5901 
  5902        now gives rise to the infinite reduction sequence
  5903 
  5904         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5905 
  5906        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5907        kind of problem.
  5908 
  5909     -- Tactics combining classical reasoner and simplification (such as auto)
  5910        are also affected by this change, because many of them rely on
  5911        simp. They may sometimes diverge as well or yield a different numbers
  5912        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5913        in case of problems. Sometimes subsequent calls to the classical
  5914        reasoner will fail because a preceeding call to the simplifier too
  5915        eagerly simplified the goal, e.g. deleted redundant premises.
  5916 
  5917   - The simplifier trace now shows the names of the applied rewrite rules
  5918 
  5919   - You can limit the number of recursive invocations of the simplifier
  5920     during conditional rewriting (where the simplifie tries to solve the
  5921     conditions before applying the rewrite rule):
  5922     ML "simp_depth_limit := n"
  5923     where n is an integer. Thus you can force termination where previously
  5924     the simplifier would diverge.
  5925 
  5926   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5927 
  5928   - No longer aborts on failed congruence proof.  Instead, the
  5929     congruence is ignored.
  5930 
  5931 * Pure: New generic framework for extracting programs from constructive
  5932   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5933   as HOL/Extraction for some case studies.
  5934 
  5935 * Pure: The main goal of the proof state is no longer shown by default, only
  5936 the subgoals. This behaviour is controlled by a new flag.
  5937    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5938 (ML: Proof.show_main_goal).
  5939 
  5940 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5941 rules whose conclusion matches subgoal 1:
  5942       PG menu: Isabelle/Isar -> Show me -> matching rules
  5943 The rules are ordered by how closely they match the subgoal.
  5944 In particular, rules that solve a subgoal outright are displayed first
  5945 (or rather last, the way they are printed).
  5946 (ML: ProofGeneral.print_intros())
  5947 
  5948 * Pure: New flag trace_unify_fail causes unification to print
  5949 diagnostic information (PG: in trace buffer) when it fails. This is
  5950 useful for figuring out why single step proofs like rule, erule or
  5951 assumption failed.
  5952 
  5953 * Pure: Locale specifications now produce predicate definitions
  5954 according to the body of text (covering assumptions modulo local
  5955 definitions); predicate "loc_axioms" covers newly introduced text,
  5956 while "loc" is cumulative wrt. all included locale expressions; the
  5957 latter view is presented only on export into the global theory
  5958 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5959 on the old view without predicates;
  5960 
  5961 * Pure: predefined locales "var" and "struct" are useful for sharing
  5962 parameters (as in CASL, for example); just specify something like
  5963 ``var x + var y + struct M'' as import;
  5964 
  5965 * Pure: improved thms_containing: proper indexing of facts instead of
  5966 raw theorems; check validity of results wrt. current name space;
  5967 include local facts of proof configuration (also covers active
  5968 locales), cover fixed variables in index; may use "_" in term
  5969 specification; an optional limit for the number of printed facts may
  5970 be given (the default is 40);
  5971 
  5972 * Pure: disallow duplicate fact bindings within new-style theory files
  5973 (batch-mode only);
  5974 
  5975 * Provers: improved induct method: assumptions introduced by case
  5976 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5977 the goal statement); "foo" still refers to all facts collectively;
  5978 
  5979 * Provers: the function blast.overloaded has been removed: all constants
  5980 are regarded as potentially overloaded, which improves robustness in exchange
  5981 for slight decrease in efficiency;
  5982 
  5983 * Provers/linorder: New generic prover for transitivity reasoning over
  5984 linear orders.  Note: this prover is not efficient!
  5985 
  5986 * Isar: preview of problems to finish 'show' now produce an error
  5987 rather than just a warning (in interactive mode);
  5988 
  5989 
  5990 *** HOL ***
  5991 
  5992 * arith(_tac)
  5993 
  5994  - Produces a counter example if it cannot prove a goal.
  5995    Note that the counter example may be spurious if the goal is not a formula
  5996    of quantifier-free linear arithmetic.
  5997    In ProofGeneral the counter example appears in the trace buffer.
  5998 
  5999  - Knows about div k and mod k where k is a numeral of type nat or int.
  6000 
  6001  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  6002    linear arithmetic fails. This takes account of quantifiers and divisibility.
  6003    Presburger arithmetic can also be called explicitly via presburger(_tac).
  6004 
  6005 * simp's arithmetic capabilities have been enhanced a bit: it now
  6006 takes ~= in premises into account (by performing a case split);
  6007 
  6008 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  6009 are distributed over a sum of terms;
  6010 
  6011 * New tactic "trans_tac" and method "trans" instantiate
  6012 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  6013 "<=", "<" and "=").
  6014 
  6015 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  6016 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  6017 
  6018 * 'typedef' command has new option "open" to suppress the set
  6019 definition;
  6020 
  6021 * functions Min and Max on finite sets have been introduced (theory
  6022 Finite_Set);
  6023 
  6024 * attribute [symmetric] now works for relations as well; it turns
  6025 (x,y) : R^-1 into (y,x) : R, and vice versa;
  6026 
  6027 * induct over a !!-quantified statement (say !!x1..xn):
  6028   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  6029 
  6030 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  6031 %x. None. Warning: empty_def now refers to the previously hidden definition
  6032 of the empty set.
  6033 
  6034 * Algebra: formalization of classical algebra.  Intended as base for
  6035 any algebraic development in Isabelle.  Currently covers group theory
  6036 (up to Sylow's theorem) and ring theory (Universal Property of
  6037 Univariate Polynomials).  Contributions welcome;
  6038 
  6039 * GroupTheory: deleted, since its material has been moved to Algebra;
  6040 
  6041 * Complex: new directory of the complex numbers with numeric constants,
  6042 nonstandard complex numbers, and some complex analysis, standard and
  6043 nonstandard (Jacques Fleuriot);
  6044 
  6045 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  6046 
  6047 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  6048 Fleuriot);
  6049 
  6050 * Real/HahnBanach: updated and adapted to locales;
  6051 
  6052 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  6053 Gray and Kramer);
  6054 
  6055 * UNITY: added the Meier-Sanders theory of progress sets;
  6056 
  6057 * MicroJava: bytecode verifier and lightweight bytecode verifier
  6058 as abstract algorithms, instantiated to the JVM;
  6059 
  6060 * Bali: Java source language formalization. Type system, operational
  6061 semantics, axiomatic semantics. Supported language features:
  6062 classes, interfaces, objects,virtual methods, static methods,
  6063 static/instance fields, arrays, access modifiers, definite
  6064 assignment, exceptions.
  6065 
  6066 
  6067 *** ZF ***
  6068 
  6069 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  6070 universe, etc.);
  6071 
  6072 * Main ZF: virtually all theories converted to new-style format;
  6073 
  6074 
  6075 *** ML ***
  6076 
  6077 * Pure: Tactic.prove provides sane interface for internal proofs;
  6078 omits the infamous "standard" operation, so this is more appropriate
  6079 than prove_goalw_cterm in many situations (e.g. in simprocs);
  6080 
  6081 * Pure: improved error reporting of simprocs;
  6082 
  6083 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  6084 up simprocs;
  6085 
  6086 
  6087 *** Document preparation ***
  6088 
  6089 * uses \par instead of \\ for line breaks in theory text. This may
  6090 shift some page breaks in large documents. To get the old behaviour
  6091 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  6092 
  6093 * minimized dependencies of isabelle.sty and isabellesym.sty on
  6094 other packages
  6095 
  6096 * \<euro> now needs package babel/greek instead of marvosym (which
  6097 broke \Rightarrow)
  6098 
  6099 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  6100 textcomp package)
  6101 
  6102 
  6103 
  6104 New in Isabelle2002 (March 2002)
  6105 --------------------------------
  6106 
  6107 *** Document preparation ***
  6108 
  6109 * greatly simplified document preparation setup, including more
  6110 graceful interpretation of isatool usedir -i/-d/-D options, and more
  6111 instructive isatool mkdir; users should basically be able to get
  6112 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  6113 users may run a separate document processing stage manually like this:
  6114 "isatool usedir -D output HOL Test && isatool document Test/output";
  6115 
  6116 * theory dependency graph may now be incorporated into documents;
  6117 isatool usedir -g true will produce session_graph.eps/.pdf for use
  6118 with \includegraphics of LaTeX;
  6119 
  6120 * proper spacing of consecutive markup elements, especially text
  6121 blocks after section headings;
  6122 
  6123 * support bold style (for single symbols only), input syntax is like
  6124 this: "\<^bold>\<alpha>" or "\<^bold>A";
  6125 
  6126 * \<bullet> is now output as bold \cdot by default, which looks much
  6127 better in printed text;
  6128 
  6129 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  6130 note that these symbols are currently unavailable in Proof General /
  6131 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  6132 
  6133 * isatool latex no longer depends on changed TEXINPUTS, instead
  6134 isatool document copies the Isabelle style files to the target
  6135 location;
  6136 
  6137 
  6138 *** Isar ***
  6139 
  6140 * Pure/Provers: improved proof by cases and induction;
  6141   - 'case' command admits impromptu naming of parameters (such as
  6142     "case (Suc n)");
  6143   - 'induct' method divinates rule instantiation from the inductive
  6144     claim; no longer requires excessive ?P bindings for proper
  6145     instantiation of cases;
  6146   - 'induct' method properly enumerates all possibilities of set/type
  6147     rules; as a consequence facts may be also passed through *type*
  6148     rules without further ado;
  6149   - 'induct' method now derives symbolic cases from the *rulified*
  6150     rule (before it used to rulify cases stemming from the internal
  6151     atomized version); this means that the context of a non-atomic
  6152     statement becomes is included in the hypothesis, avoiding the
  6153     slightly cumbersome show "PROP ?case" form;
  6154   - 'induct' may now use elim-style induction rules without chaining
  6155     facts, using ``missing'' premises from the goal state; this allows
  6156     rules stemming from inductive sets to be applied in unstructured
  6157     scripts, while still benefitting from proper handling of non-atomic
  6158     statements; NB: major inductive premises need to be put first, all
  6159     the rest of the goal is passed through the induction;
  6160   - 'induct' proper support for mutual induction involving non-atomic
  6161     rule statements (uses the new concept of simultaneous goals, see
  6162     below);
  6163   - append all possible rule selections, but only use the first
  6164     success (no backtracking);
  6165   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  6166   - undeclared rule case names default to numbers 1, 2, 3, ...;
  6167   - added 'print_induct_rules' (covered by help item in recent Proof
  6168     General versions);
  6169   - moved induct/cases attributes to Pure, methods to Provers;
  6170   - generic method setup instantiated for FOL and HOL;
  6171 
  6172 * Pure: support multiple simultaneous goal statements, for example
  6173 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  6174 meta-level mechanism, this acts as if several individual goals had
  6175 been stated separately; in particular common proof methods need to be
  6176 repeated in order to cover all claims; note that a single elimination
  6177 step is *not* sufficient to establish the two conjunctions, so this
  6178 fails:
  6179 
  6180   assume "A & B" then have A and B ..   (*".." fails*)
  6181 
  6182 better use "obtain" in situations as above; alternative refer to
  6183 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  6184 
  6185 * Pure: proper integration with ``locales''; unlike the original
  6186 version by Florian Kammller, Isar locales package high-level proof
  6187 contexts rather than raw logical ones (e.g. we admit to include
  6188 attributes everywhere); operations on locales include merge and
  6189 rename; support for implicit arguments (``structures''); simultaneous
  6190 type-inference over imports and text; see also HOL/ex/Locales.thy for
  6191 some examples;
  6192 
  6193 * Pure: the following commands have been ``localized'', supporting a
  6194 target locale specification "(in name)": 'lemma', 'theorem',
  6195 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  6196 stored both within the locale and at the theory level (exported and
  6197 qualified by the locale name);
  6198 
  6199 * Pure: theory goals may now be specified in ``long'' form, with
  6200 ad-hoc contexts consisting of arbitrary locale elements. for example
  6201 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  6202 definitions may be given, too); the result is a meta-level rule with
  6203 the context elements being discharged in the obvious way;
  6204 
  6205 * Pure: new proof command 'using' allows to augment currently used
  6206 facts after a goal statement ('using' is syntactically analogous to
  6207 'apply', but acts on the goal's facts only); this allows chained facts
  6208 to be separated into parts given before and after a claim, as in
  6209 ``from a and b have C using d and e <proof>'';
  6210 
  6211 * Pure: renamed "antecedent" case to "rule_context";
  6212 
  6213 * Pure: new 'judgment' command records explicit information about the
  6214 object-logic embedding (used by several tools internally); no longer
  6215 use hard-wired "Trueprop";
  6216 
  6217 * Pure: added 'corollary' command;
  6218 
  6219 * Pure: fixed 'token_translation' command;
  6220 
  6221 * Pure: removed obsolete 'exported' attribute;
  6222 
  6223 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  6224 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  6225 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  6226 
  6227 * Pure: method 'atomize' presents local goal premises as object-level
  6228 statements (atomic meta-level propositions); setup controlled via
  6229 rewrite rules declarations of 'atomize' attribute; example
  6230 application: 'induct' method with proper rule statements in improper