NEWS
author haftmann
Sun Jul 24 21:27:25 2011 +0200 (2011-07-24)
changeset 43967 610efb6bda1f
parent 43940 26ca0bad226a
child 43970 3d204d261903
permissions -rw-r--r--
more coherent structure in and across theories
     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 orderes.  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 * Archimedian_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     
   101 * Declare ext [intro] by default.  Rare INCOMPATIBILITY.
   102 
   103 * Nitpick:
   104   - Added "need" and "total_consts" options.
   105   - Reintroduced "show_skolems" option by popular demand.
   106   - Renamed attribute: nitpick_def ~> nitpick_unfold.
   107     INCOMPATIBILITY.
   108 
   109 * Sledgehammer:
   110   - sledgehammer available_provers ~> sledgehammer supported_provers.
   111     INCOMPATIBILITY.
   112   - Added support for SNARK and ToFoF-E on SystemOnTPTP and for simply typed
   113     TPTP problems (TFF).
   114   - Added "preplay_timeout", "slicing", "type_enc", "sound", "max_mono_iters",
   115     and "max_new_mono_instances" options.
   116   - Removed "explicit_apply" and "full_types" options as well as "Full Types"
   117     Proof General menu item. INCOMPATIBILITY.
   118 
   119 * Metis:
   120   - Removed "metisF" -- use "metis" instead. INCOMPATIBILITY.
   121   - Obsoleted "metisFT" -- use "metis (full_types)" instead. INCOMPATIBILITY.
   122 
   123 * "try":
   124   - Renamed "try_methods" and added "simp:", "intro:", "dest:", and "elim:"
   125     options. INCOMPATIBILITY.
   126   - Introduced "try" that not only runs "try_methods" but also "solve_direct",
   127     "sledgehammer", "quickcheck", and "nitpick".
   128 
   129 * Quickcheck:
   130   - Added "eval" option to evaluate terms for the found counterexample
   131     (currently only supported by the default (exhaustive) tester)
   132   - Added post-processing of terms to obtain readable counterexamples
   133     (currently only supported by the default (exhaustive) tester)
   134   - New counterexample generator quickcheck[narrowing] enables
   135     narrowing-based testing.
   136     It requires that the Glasgow Haskell compiler is installed and
   137     its location is known to Isabelle with the environment variable
   138     ISABELLE_GHC.
   139 
   140 * Function package: discontinued option "tailrec".
   141 INCOMPATIBILITY. Use partial_function instead.
   142 
   143 * HOL-Probability:
   144   - Caratheodory's extension lemma is now proved for ring_of_sets.
   145   - Infinite products of probability measures are now available.
   146   - Use extended reals instead of positive extended reals.
   147     INCOMPATIBILITY.
   148 
   149 
   150 *** Document preparation ***
   151 
   152 * Discontinued special treatment of hard tabulators, which are better
   153 avoided in the first place.  Implicit tab-width is 1.
   154 
   155 * Antiquotation @{rail} layouts railroad syntax diagrams, see also
   156 isar-ref manual.
   157 
   158 * Antiquotation @{value} evaluates the given term and presents its result.
   159 
   160 * Localized \isabellestyle switch can be used within blocks or groups
   161 like this:
   162 
   163   \isabellestyle{it}  %preferred default
   164   {\isabellestylett @{text "typewriter stuff"}}
   165 
   166 * New term style "isub" as ad-hoc conversion of variables x1, y23 into
   167 subscripted form x\<^isub>1, y\<^isub>2\<^isub>3.
   168 
   169 * Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
   170 (e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).
   171 
   172 
   173 *** ML ***
   174 
   175 * The inner syntax of sort/type/term/prop supports inlined YXML
   176 representations within quoted string tokens.  By encoding logical
   177 entities via Term_XML (in ML or Scala) concrete syntax can be
   178 bypassed, which is particularly useful for producing bits of text
   179 under external program control.
   180 
   181 * Antiquotations for ML and document preparation are managed as theory
   182 data, which requires explicit setup.
   183 
   184 * Isabelle_Process.is_active allows tools to check if the official
   185 process wrapper is running (Isabelle/Scala/jEdit) or the old TTY loop
   186 (better known as Proof General).
   187 
   188 * Structure Proof_Context follows standard naming scheme.  Old
   189 ProofContext is still available for some time as legacy alias.
   190 
   191 * Structure Timing provides various operations for timing; supersedes
   192 former start_timing/end_timing etc.
   193 
   194 * Path.print is the official way to show file-system paths to users
   195 (including quotes etc.).
   196 
   197 * Inner syntax: identifiers in parse trees of generic categories
   198 "logic", "aprop", "idt" etc. carry position information (disguised as
   199 type constraints).  Occasional INCOMPATIBILITY with non-compliant
   200 translations that choke on unexpected type constraints.  Positions can
   201 be stripped in ML translations via Syntax.strip_positions /
   202 Syntax.strip_positions_ast, or via the syntax constant
   203 "_strip_positions" within parse trees.  As last resort, positions can
   204 be disabled via the configuration option Syntax.positions, which is
   205 called "syntax_positions" in Isar attribute syntax.
   206 
   207 * Discontinued special status of various ML structures that contribute
   208 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
   209 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
   210 refer directly to Ast.Constant, Lexicon.is_identifier,
   211 Syntax_Trans.mk_binder_tr etc.
   212 
   213 * Typed print translation: discontinued show_sorts argument, which is
   214 already available via context of "advanced" translation.
   215 
   216 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
   217 goal states; body tactic needs to address all subgoals uniformly.
   218 
   219 * Slightly more special eq_list/eq_set, with shortcut involving
   220 pointer equality (assumes that eq relation is reflexive).
   221 
   222 * Classical tactics use proper Proof.context instead of historic types
   223 claset/clasimpset.  Old-style declarations like addIs, addEs, addDs
   224 operate directly on Proof.context.  Raw type claset retains its use as
   225 snapshot of the classical context, which can be recovered via
   226 (put_claset HOL_cs) etc.  Type clasimpset has been discontinued.
   227 INCOMPATIBILITY, classical tactics and derived proof methods require
   228 proper Proof.context.
   229 
   230 * Scala layer provides JVM method invocation service for static
   231 methods of type (String)String, see Invoke_Scala.method in ML.
   232 For example:
   233 
   234   Invoke_Scala.method "java.lang.System.getProperty" "java.home"
   235 
   236 
   237 
   238 New in Isabelle2011 (January 2011)
   239 ----------------------------------
   240 
   241 *** General ***
   242 
   243 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
   244 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
   245 useful tooltips and hyperlinks produced from its static analysis.  The
   246 bundled component provides an executable Isabelle tool that can be run
   247 like this:
   248 
   249   Isabelle2011/bin/isabelle jedit
   250 
   251 * Significantly improved Isabelle/Isar implementation manual.
   252 
   253 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
   254 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
   255 while the default heap location within that directory lacks that extra
   256 suffix.  This isolates multiple Isabelle installations from each
   257 other, avoiding problems with old settings in new versions.
   258 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
   259 
   260 * Source files are always encoded as UTF-8, instead of old-fashioned
   261 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
   262 the following package declarations:
   263 
   264   \usepackage[utf8]{inputenc}
   265   \usepackage{textcomp}
   266 
   267 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
   268 a Unicode character is treated as a single symbol, not a sequence of
   269 non-ASCII bytes as before.  Since Isabelle/ML string literals may
   270 contain symbols without further backslash escapes, Unicode can now be
   271 used here as well.  Recall that Symbol.explode in ML provides a
   272 consistent view on symbols, while raw explode (or String.explode)
   273 merely give a byte-oriented representation.
   274 
   275 * Theory loader: source files are primarily located via the master
   276 directory of each theory node (where the .thy file itself resides).
   277 The global load path is still partially available as legacy feature.
   278 Minor INCOMPATIBILITY due to subtle change in file lookup: use
   279 explicit paths, relatively to the theory.
   280 
   281 * Special treatment of ML file names has been discontinued.
   282 Historically, optional extensions .ML or .sml were added on demand --
   283 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
   284 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
   285 
   286 * Various options that affect pretty printing etc. are now properly
   287 handled within the context via configuration options, instead of
   288 unsynchronized references or print modes.  There are both ML Config.T
   289 entities and Isar declaration attributes to access these.
   290 
   291   ML (Config.T)                 Isar (attribute)
   292 
   293   eta_contract                  eta_contract
   294   show_brackets                 show_brackets
   295   show_sorts                    show_sorts
   296   show_types                    show_types
   297   show_question_marks           show_question_marks
   298   show_consts                   show_consts
   299   show_abbrevs                  show_abbrevs
   300 
   301   Syntax.ast_trace              syntax_ast_trace
   302   Syntax.ast_stat               syntax_ast_stat
   303   Syntax.ambiguity_level        syntax_ambiguity_level
   304 
   305   Goal_Display.goals_limit      goals_limit
   306   Goal_Display.show_main_goal   show_main_goal
   307 
   308   Method.rule_trace             rule_trace
   309 
   310   Thy_Output.display            thy_output_display
   311   Thy_Output.quotes             thy_output_quotes
   312   Thy_Output.indent             thy_output_indent
   313   Thy_Output.source             thy_output_source
   314   Thy_Output.break              thy_output_break
   315 
   316 Note that corresponding "..._default" references in ML may only be
   317 changed globally at the ROOT session setup, but *not* within a theory.
   318 The option "show_abbrevs" supersedes the former print mode
   319 "no_abbrevs" with inverted meaning.
   320 
   321 * More systematic naming of some configuration options.
   322 INCOMPATIBILITY.
   323 
   324   trace_simp  ~>  simp_trace
   325   debug_simp  ~>  simp_debug
   326 
   327 * Support for real valued configuration options, using simplistic
   328 floating-point notation that coincides with the inner syntax for
   329 float_token.
   330 
   331 * Support for real valued preferences (with approximative PGIP type):
   332 front-ends need to accept "pgint" values in float notation.
   333 INCOMPATIBILITY.
   334 
   335 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
   336 DejaVu Sans.
   337 
   338 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   339 
   340 
   341 *** Pure ***
   342 
   343 * Command 'type_synonym' (with single argument) replaces somewhat
   344 outdated 'types', which is still available as legacy feature for some
   345 time.
   346 
   347 * Command 'nonterminal' (with 'and' separated list of arguments)
   348 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
   349 
   350 * Command 'notepad' replaces former 'example_proof' for
   351 experimentation in Isar without any result.  INCOMPATIBILITY.
   352 
   353 * Locale interpretation commands 'interpret' and 'sublocale' accept
   354 lists of equations to map definitions in a locale to appropriate
   355 entities in the context of the interpretation.  The 'interpretation'
   356 command already provided this functionality.
   357 
   358 * Diagnostic command 'print_dependencies' prints the locale instances
   359 that would be activated if the specified expression was interpreted in
   360 the current context.  Variant "print_dependencies!" assumes a context
   361 without interpretations.
   362 
   363 * Diagnostic command 'print_interps' prints interpretations in proofs
   364 in addition to interpretations in theories.
   365 
   366 * Discontinued obsolete 'global' and 'local' commands to manipulate
   367 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
   368 Sign.root_path and Sign.local_path may be applied directly where this
   369 feature is still required for historical reasons.
   370 
   371 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
   372 'definition' instead.
   373 
   374 * The "prems" fact, which refers to the accidental collection of
   375 foundational premises in the context, is now explicitly marked as
   376 legacy feature and will be discontinued soon.  Consider using "assms"
   377 of the head statement or reference facts by explicit names.
   378 
   379 * Document antiquotations @{class} and @{type} print classes and type
   380 constructors.
   381 
   382 * Document antiquotation @{file} checks file/directory entries within
   383 the local file system.
   384 
   385 
   386 *** HOL ***
   387 
   388 * Coercive subtyping: functions can be declared as coercions and type
   389 inference will add them as necessary upon input of a term.  Theory
   390 Complex_Main declares real :: nat => real and real :: int => real as
   391 coercions. A coercion function f is declared like this:
   392 
   393   declare [[coercion f]]
   394 
   395 To lift coercions through type constructors (e.g. from nat => real to
   396 nat list => real list), map functions can be declared, e.g.
   397 
   398   declare [[coercion_map map]]
   399 
   400 Currently coercion inference is activated only in theories including
   401 real numbers, i.e. descendants of Complex_Main.  This is controlled by
   402 the configuration option "coercion_enabled", e.g. it can be enabled in
   403 other theories like this:
   404 
   405   declare [[coercion_enabled]]
   406 
   407 * Command 'partial_function' provides basic support for recursive
   408 function definitions over complete partial orders.  Concrete instances
   409 are provided for i) the option type, ii) tail recursion on arbitrary
   410 types, and iii) the heap monad of Imperative_HOL.  See
   411 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
   412 for examples.
   413 
   414 * Function package: f.psimps rules are no longer implicitly declared
   415 as [simp].  INCOMPATIBILITY.
   416 
   417 * Datatype package: theorems generated for executable equality (class
   418 "eq") carry proper names and are treated as default code equations.
   419 
   420 * Inductive package: now offers command 'inductive_simps' to
   421 automatically derive instantiated and simplified equations for
   422 inductive predicates, similar to 'inductive_cases'.
   423 
   424 * Command 'enriched_type' allows to register properties of the
   425 functorial structure of types.
   426 
   427 * Improved infrastructure for term evaluation using code generator
   428 techniques, in particular static evaluation conversions.
   429 
   430 * Code generator: Scala (2.8 or higher) has been added to the target
   431 languages.
   432 
   433 * Code generator: globbing constant expressions "*" and "Theory.*"
   434 have been replaced by the more idiomatic "_" and "Theory._".
   435 INCOMPATIBILITY.
   436 
   437 * Code generator: export_code without explicit file declaration prints
   438 to standard output.  INCOMPATIBILITY.
   439 
   440 * Code generator: do not print function definitions for case
   441 combinators any longer.
   442 
   443 * Code generator: simplification with rules determined with
   444 src/Tools/Code/code_simp.ML and method "code_simp".
   445 
   446 * Code generator for records: more idiomatic representation of record
   447 types.  Warning: records are not covered by ancient SML code
   448 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
   449 rep_datatype declaration helps to succeed then:
   450 
   451   record 'a foo = ...
   452   ...
   453   rep_datatype foo_ext ...
   454 
   455 * Records: logical foundation type for records does not carry a
   456 '_type' suffix any longer (obsolete due to authentic syntax).
   457 INCOMPATIBILITY.
   458 
   459 * Quickcheck now by default uses exhaustive testing instead of random
   460 testing.  Random testing can be invoked by "quickcheck [random]",
   461 exhaustive testing by "quickcheck [exhaustive]".
   462 
   463 * Quickcheck instantiates polymorphic types with small finite
   464 datatypes by default. This enables a simple execution mechanism to
   465 handle quantifiers and function equality over the finite datatypes.
   466 
   467 * Quickcheck random generator has been renamed from "code" to
   468 "random".  INCOMPATIBILITY.
   469 
   470 * Quickcheck now has a configurable time limit which is set to 30
   471 seconds by default. This can be changed by adding [timeout = n] to the
   472 quickcheck command. The time limit for Auto Quickcheck is still set
   473 independently.
   474 
   475 * Quickcheck in locales considers interpretations of that locale for
   476 counter example search.
   477 
   478 * Sledgehammer:
   479   - Added "smt" and "remote_smt" provers based on the "smt" proof
   480     method. See the Sledgehammer manual for details ("isabelle doc
   481     sledgehammer").
   482   - Renamed commands:
   483     sledgehammer atp_info ~> sledgehammer running_provers
   484     sledgehammer atp_kill ~> sledgehammer kill_provers
   485     sledgehammer available_atps ~> sledgehammer available_provers
   486     INCOMPATIBILITY.
   487   - Renamed options:
   488     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
   489     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
   490     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
   491     (and "ms" and "min" are no longer supported)
   492     INCOMPATIBILITY.
   493 
   494 * Nitpick:
   495   - Renamed options:
   496     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
   497     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
   498     INCOMPATIBILITY.
   499   - Added support for partial quotient types.
   500   - Added local versions of the "Nitpick.register_xxx" functions.
   501   - Added "whack" option.
   502   - Allow registration of quotient types as codatatypes.
   503   - Improved "merge_type_vars" option to merge more types.
   504   - Removed unsound "fast_descrs" option.
   505   - Added custom symmetry breaking for datatypes, making it possible to reach
   506     higher cardinalities.
   507   - Prevent the expansion of too large definitions.
   508 
   509 * Proof methods "metis" and "meson" now have configuration options
   510 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
   511 to diagnose these tools. E.g.
   512 
   513     using [[metis_trace = true]]
   514 
   515 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
   516 manually as command 'solve_direct'.
   517 
   518 * The default SMT solver Z3 must be enabled explicitly (due to
   519 licensing issues) by setting the environment variable
   520 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
   521 commercial applications, the SMT solver CVC3 is provided as fall-back;
   522 changing the SMT solver is done via the configuration option
   523 "smt_solver".
   524 
   525 * Remote SMT solvers need to be referred to by the "remote_" prefix,
   526 i.e. "remote_cvc3" and "remote_z3".
   527 
   528 * Added basic SMT support for datatypes, records, and typedefs using
   529 the oracle mode (no proofs).  Direct support of pairs has been dropped
   530 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
   531 support for a similar behavior).  Minor INCOMPATIBILITY.
   532 
   533 * Changed SMT configuration options:
   534   - Renamed:
   535     z3_proofs ~> smt_oracle (with inverted meaning)
   536     z3_trace_assms ~> smt_trace_used_facts
   537     INCOMPATIBILITY.
   538   - Added:
   539     smt_verbose
   540     smt_random_seed
   541     smt_datatypes
   542     smt_infer_triggers
   543     smt_monomorph_limit
   544     cvc3_options
   545     remote_cvc3_options
   546     remote_z3_options
   547     yices_options
   548 
   549 * Boogie output files (.b2i files) need to be declared in the theory
   550 header.
   551 
   552 * Simplification procedure "list_to_set_comprehension" rewrites list
   553 comprehensions applied to List.set to set comprehensions.  Occasional
   554 INCOMPATIBILITY, may be deactivated like this:
   555 
   556   declare [[simproc del: list_to_set_comprehension]]
   557 
   558 * Removed old version of primrec package.  INCOMPATIBILITY.
   559 
   560 * Removed simplifier congruence rule of "prod_case", as has for long
   561 been the case with "split".  INCOMPATIBILITY.
   562 
   563 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
   564 
   565 * Removed [split_format ... and ... and ...] version of
   566 [split_format].  Potential INCOMPATIBILITY.
   567 
   568 * Predicate "sorted" now defined inductively, with nice induction
   569 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
   570 
   571 * Constant "contents" renamed to "the_elem", to free the generic name
   572 contents for other uses.  INCOMPATIBILITY.
   573 
   574 * Renamed class eq and constant eq (for code generation) to class
   575 equal and constant equal, plus renaming of related facts and various
   576 tuning.  INCOMPATIBILITY.
   577 
   578 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
   579 
   580 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
   581 INCOMPATIBILITY.
   582 
   583 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
   584 avoid confusion with finite sets.  INCOMPATIBILITY.
   585 
   586 * Abandoned locales equiv, congruent and congruent2 for equivalence
   587 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
   588 for congruent(2)).
   589 
   590 * Some previously unqualified names have been qualified:
   591 
   592   types
   593     bool ~> HOL.bool
   594     nat ~> Nat.nat
   595 
   596   constants
   597     Trueprop ~> HOL.Trueprop
   598     True ~> HOL.True
   599     False ~> HOL.False
   600     op & ~> HOL.conj
   601     op | ~> HOL.disj
   602     op --> ~> HOL.implies
   603     op = ~> HOL.eq
   604     Not ~> HOL.Not
   605     The ~> HOL.The
   606     All ~> HOL.All
   607     Ex ~> HOL.Ex
   608     Ex1 ~> HOL.Ex1
   609     Let ~> HOL.Let
   610     If ~> HOL.If
   611     Ball ~> Set.Ball
   612     Bex ~> Set.Bex
   613     Suc ~> Nat.Suc
   614     Pair ~> Product_Type.Pair
   615     fst ~> Product_Type.fst
   616     snd ~> Product_Type.snd
   617     curry ~> Product_Type.curry
   618     op : ~> Set.member
   619     Collect ~> Set.Collect
   620 
   621 INCOMPATIBILITY.
   622 
   623 * More canonical naming convention for some fundamental definitions:
   624 
   625     bot_bool_eq ~> bot_bool_def
   626     top_bool_eq ~> top_bool_def
   627     inf_bool_eq ~> inf_bool_def
   628     sup_bool_eq ~> sup_bool_def
   629     bot_fun_eq  ~> bot_fun_def
   630     top_fun_eq  ~> top_fun_def
   631     inf_fun_eq  ~> inf_fun_def
   632     sup_fun_eq  ~> sup_fun_def
   633 
   634 INCOMPATIBILITY.
   635 
   636 * More stylized fact names:
   637 
   638   expand_fun_eq ~> fun_eq_iff
   639   expand_set_eq ~> set_eq_iff
   640   set_ext       ~> set_eqI
   641   nat_number    ~> eval_nat_numeral
   642 
   643 INCOMPATIBILITY.
   644 
   645 * Refactoring of code-generation specific operations in theory List:
   646 
   647   constants
   648     null ~> List.null
   649 
   650   facts
   651     mem_iff ~> member_def
   652     null_empty ~> null_def
   653 
   654 INCOMPATIBILITY.  Note that these were not supposed to be used
   655 regularly unless for striking reasons; their main purpose was code
   656 generation.
   657 
   658 Various operations from the Haskell prelude are used for generating
   659 Haskell code.
   660 
   661 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
   662 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
   663 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
   664 
   665 * Abolished some non-alphabetic type names: "prod" and "sum" replace
   666 "*" and "+" respectively.  INCOMPATIBILITY.
   667 
   668 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
   669 "Sum_Type.Plus" instead.
   670 
   671 * Constant "split" has been merged with constant "prod_case"; names of
   672 ML functions, facts etc. involving split have been retained so far,
   673 though.  INCOMPATIBILITY.
   674 
   675 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
   676 instead.  INCOMPATIBILITY.
   677 
   678 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
   679 INCOMPATIBILITY.
   680 
   681 * Former theory Library/Enum is now part of the HOL-Main image.
   682 INCOMPATIBILITY: all constants of the Enum theory now have to be
   683 referred to by its qualified name.
   684 
   685   enum    ~>  Enum.enum
   686   nlists  ~>  Enum.nlists
   687   product ~>  Enum.product
   688 
   689 * Theory Library/Monad_Syntax provides do-syntax for monad types.
   690 Syntax in Library/State_Monad has been changed to avoid ambiguities.
   691 INCOMPATIBILITY.
   692 
   693 * Theory Library/SetsAndFunctions has been split into
   694 Library/Function_Algebras and Library/Set_Algebras; canonical names
   695 for instance definitions for functions; various improvements.
   696 INCOMPATIBILITY.
   697 
   698 * Theory Library/Multiset provides stable quicksort implementation of
   699 sort_key.
   700 
   701 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
   702 INCOMPATIBILITY.
   703 
   704 * Session Multivariate_Analysis: introduced a type class for euclidean
   705 space.  Most theorems are now stated in terms of euclidean spaces
   706 instead of finite cartesian products.
   707 
   708   types
   709     real ^ 'n ~>  'a::real_vector
   710               ~>  'a::euclidean_space
   711               ~>  'a::ordered_euclidean_space
   712         (depends on your needs)
   713 
   714   constants
   715      _ $ _        ~> _ $$ _
   716      \<chi> x. _  ~> \<chi>\<chi> x. _
   717      CARD('n)     ~> DIM('a)
   718 
   719 Also note that the indices are now natural numbers and not from some
   720 finite type. Finite cartesian products of euclidean spaces, products
   721 of euclidean spaces the real and complex numbers are instantiated to
   722 be euclidean_spaces.  INCOMPATIBILITY.
   723 
   724 * Session Probability: introduced pextreal as positive extended real
   725 numbers.  Use pextreal as value for measures.  Introduce the
   726 Radon-Nikodym derivative, product spaces and Fubini's theorem for
   727 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
   728 the integral in Multivariate Analysis.  INCOMPATIBILITY.
   729 
   730 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   731 INCOMPATIBILITY.
   732 
   733 * Session SPARK (with image HOL-SPARK) provides commands to load and
   734 prove verification conditions generated by the SPARK Ada program
   735 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
   736 
   737 
   738 *** HOL-Algebra ***
   739 
   740 * Theorems for additive ring operations (locale abelian_monoid and
   741 descendants) are generated by interpretation from their multiplicative
   742 counterparts.  Names (in particular theorem names) have the mandatory
   743 qualifier 'add'.  Previous theorem names are redeclared for
   744 compatibility.
   745 
   746 * Structure "int_ring" is now an abbreviation (previously a
   747 definition).  This fits more natural with advanced interpretations.
   748 
   749 
   750 *** HOLCF ***
   751 
   752 * The domain package now runs in definitional mode by default: The
   753 former command 'new_domain' is now called 'domain'.  To use the domain
   754 package in its original axiomatic mode, use 'domain (unsafe)'.
   755 INCOMPATIBILITY.
   756 
   757 * The new class "domain" is now the default sort.  Class "predomain"
   758 is an unpointed version of "domain". Theories can be updated by
   759 replacing sort annotations as shown below.  INCOMPATIBILITY.
   760 
   761   'a::type ~> 'a::countable
   762   'a::cpo  ~> 'a::predomain
   763   'a::pcpo ~> 'a::domain
   764 
   765 * The old type class "rep" has been superseded by class "domain".
   766 Accordingly, users of the definitional package must remove any
   767 "default_sort rep" declarations.  INCOMPATIBILITY.
   768 
   769 * The domain package (definitional mode) now supports unpointed
   770 predomain argument types, as long as they are marked 'lazy'. (Strict
   771 arguments must be in class "domain".) For example, the following
   772 domain definition now works:
   773 
   774   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
   775 
   776 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
   777 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
   778 'a option, and 'a list.  Additionally, it configures fixrec and the
   779 domain package to work with these types.  For example:
   780 
   781   fixrec isInl :: "('a + 'b) u -> tr"
   782     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
   783 
   784   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
   785 
   786 * The "(permissive)" option of fixrec has been replaced with a
   787 per-equation "(unchecked)" option. See
   788 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
   789 
   790 * The "bifinite" class no longer fixes a constant "approx"; the class
   791 now just asserts that such a function exists.  INCOMPATIBILITY.
   792 
   793 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
   794 defines an embedding of type 'a defl into udom by default; instances
   795 of "bifinite" and "domain" classes are available in
   796 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
   797 
   798 * The syntax "REP('a)" has been replaced with "DEFL('a)".
   799 
   800 * The predicate "directed" has been removed.  INCOMPATIBILITY.
   801 
   802 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
   803 
   804 * The function "cprod_map" has been renamed to "prod_map".
   805 INCOMPATIBILITY.
   806 
   807 * The monadic bind operator on each powerdomain has new binder syntax
   808 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
   809 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
   810 
   811 * The infix syntax for binary union on each powerdomain has changed
   812 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
   813 syntax.  INCOMPATIBILITY.
   814 
   815 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
   816 still supported as an input translation.
   817 
   818 * Renamed some theorems (the original names are also still available).
   819 
   820   expand_fun_below   ~> fun_below_iff
   821   below_fun_ext      ~> fun_belowI
   822   expand_cfun_eq     ~> cfun_eq_iff
   823   ext_cfun           ~> cfun_eqI
   824   expand_cfun_below  ~> cfun_below_iff
   825   below_cfun_ext     ~> cfun_belowI
   826   cont2cont_Rep_CFun ~> cont2cont_APP
   827 
   828 * The Abs and Rep functions for various types have changed names.
   829 Related theorem names have also changed to match. INCOMPATIBILITY.
   830 
   831   Rep_CFun  ~> Rep_cfun
   832   Abs_CFun  ~> Abs_cfun
   833   Rep_Sprod ~> Rep_sprod
   834   Abs_Sprod ~> Abs_sprod
   835   Rep_Ssum  ~> Rep_ssum
   836   Abs_Ssum  ~> Abs_ssum
   837 
   838 * Lemmas with names of the form *_defined_iff or *_strict_iff have
   839 been renamed to *_bottom_iff.  INCOMPATIBILITY.
   840 
   841 * Various changes to bisimulation/coinduction with domain package:
   842 
   843   - Definitions of "bisim" constants no longer mention definedness.
   844   - With mutual recursion, "bisim" predicate is now curried.
   845   - With mutual recursion, each type gets a separate coind theorem.
   846   - Variable names in bisim_def and coinduct rules have changed.
   847 
   848 INCOMPATIBILITY.
   849 
   850 * Case combinators generated by the domain package for type "foo" are
   851 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
   852 
   853 * Several theorems have been renamed to more accurately reflect the
   854 names of constants and types involved.  INCOMPATIBILITY.
   855 
   856   thelub_const    ~> lub_const
   857   lub_const       ~> is_lub_const
   858   thelubI         ~> lub_eqI
   859   is_lub_lub      ~> is_lubD2
   860   lubI            ~> is_lub_lub
   861   unique_lub      ~> is_lub_unique
   862   is_ub_lub       ~> is_lub_rangeD1
   863   lub_bin_chain   ~> is_lub_bin_chain
   864   lub_fun         ~> is_lub_fun
   865   thelub_fun      ~> lub_fun
   866   thelub_cfun     ~> lub_cfun
   867   thelub_Pair     ~> lub_Pair
   868   lub_cprod       ~> is_lub_prod
   869   thelub_cprod    ~> lub_prod
   870   minimal_cprod   ~> minimal_prod
   871   inst_cprod_pcpo ~> inst_prod_pcpo
   872   UU_I            ~> bottomI
   873   compact_UU      ~> compact_bottom
   874   deflation_UU    ~> deflation_bottom
   875   finite_deflation_UU ~> finite_deflation_bottom
   876 
   877 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
   878 
   879   sq_ord_less_eq_trans ~> below_eq_trans
   880   sq_ord_eq_less_trans ~> eq_below_trans
   881   refl_less            ~> below_refl
   882   trans_less           ~> below_trans
   883   antisym_less         ~> below_antisym
   884   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
   885   box_less             ~> box_below
   886   rev_trans_less       ~> rev_below_trans
   887   not_less2not_eq      ~> not_below2not_eq
   888   less_UU_iff          ~> below_UU_iff
   889   flat_less_iff        ~> flat_below_iff
   890   adm_less             ~> adm_below
   891   adm_not_less         ~> adm_not_below
   892   adm_compact_not_less ~> adm_compact_not_below
   893   less_fun_def         ~> below_fun_def
   894   expand_fun_less      ~> fun_below_iff
   895   less_fun_ext         ~> fun_belowI
   896   less_discr_def       ~> below_discr_def
   897   discr_less_eq        ~> discr_below_eq
   898   less_unit_def        ~> below_unit_def
   899   less_cprod_def       ~> below_prod_def
   900   prod_lessI           ~> prod_belowI
   901   Pair_less_iff        ~> Pair_below_iff
   902   fst_less_iff         ~> fst_below_iff
   903   snd_less_iff         ~> snd_below_iff
   904   expand_cfun_less     ~> cfun_below_iff
   905   less_cfun_ext        ~> cfun_belowI
   906   injection_less       ~> injection_below
   907   less_up_def          ~> below_up_def
   908   not_Iup_less         ~> not_Iup_below
   909   Iup_less             ~> Iup_below
   910   up_less              ~> up_below
   911   Def_inject_less_eq   ~> Def_below_Def
   912   Def_less_is_eq       ~> Def_below_iff
   913   spair_less_iff       ~> spair_below_iff
   914   less_sprod           ~> below_sprod
   915   spair_less           ~> spair_below
   916   sfst_less_iff        ~> sfst_below_iff
   917   ssnd_less_iff        ~> ssnd_below_iff
   918   fix_least_less       ~> fix_least_below
   919   dist_less_one        ~> dist_below_one
   920   less_ONE             ~> below_ONE
   921   ONE_less_iff         ~> ONE_below_iff
   922   less_sinlD           ~> below_sinlD
   923   less_sinrD           ~> below_sinrD
   924 
   925 
   926 *** FOL and ZF ***
   927 
   928 * All constant names are now qualified internally and use proper
   929 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
   930 
   931 
   932 *** ML ***
   933 
   934 * Antiquotation @{assert} inlines a function bool -> unit that raises
   935 Fail if the argument is false.  Due to inlining the source position of
   936 failed assertions is included in the error output.
   937 
   938 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
   939 text is in practice always evaluated with a stable theory checkpoint.
   940 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
   941 
   942 * Antiquotation @{theory A} refers to theory A from the ancestry of
   943 the current context, not any accidental theory loader state as before.
   944 Potential INCOMPATIBILITY, subtle change in semantics.
   945 
   946 * Syntax.pretty_priority (default 0) configures the required priority
   947 of pretty-printed output and thus affects insertion of parentheses.
   948 
   949 * Syntax.default_root (default "any") configures the inner syntax
   950 category (nonterminal symbol) for parsing of terms.
   951 
   952 * Former exception Library.UnequalLengths now coincides with
   953 ListPair.UnequalLengths.
   954 
   955 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
   956 main functionality is provided by structure Simplifier.
   957 
   958 * Renamed raw "explode" function to "raw_explode" to emphasize its
   959 meaning.  Note that internally to Isabelle, Symbol.explode is used in
   960 almost all situations.
   961 
   962 * Discontinued obsolete function sys_error and exception SYS_ERROR.
   963 See implementation manual for further details on exceptions in
   964 Isabelle/ML.
   965 
   966 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
   967 meaning.
   968 
   969 * Renamed structure PureThy to Pure_Thy and moved most of its
   970 operations to structure Global_Theory, to emphasize that this is
   971 rarely-used global-only stuff.
   972 
   973 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
   974 instead (or tracing for high-volume output).
   975 
   976 * Configuration option show_question_marks only affects regular pretty
   977 printing of types and terms, not raw Term.string_of_vname.
   978 
   979 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
   980 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
   981 @{thms} for most purposes.
   982 
   983 * ML structure Unsynchronized is never opened, not even in Isar
   984 interaction mode as before.  Old Unsynchronized.set etc. have been
   985 discontinued -- use plain := instead.  This should be *rare* anyway,
   986 since modern tools always work via official context data, notably
   987 configuration options.
   988 
   989 * Parallel and asynchronous execution requires special care concerning
   990 interrupts.  Structure Exn provides some convenience functions that
   991 avoid working directly with raw Interrupt.  User code must not absorb
   992 interrupts -- intermediate handling (for cleanup etc.) needs to be
   993 followed by re-raising of the original exception.  Another common
   994 source of mistakes are "handle _" patterns, which make the meaning of
   995 the program subject to physical effects of the environment.
   996 
   997 
   998 
   999 New in Isabelle2009-2 (June 2010)
  1000 ---------------------------------
  1001 
  1002 *** General ***
  1003 
  1004 * Authentic syntax for *all* logical entities (type classes, type
  1005 constructors, term constants): provides simple and robust
  1006 correspondence between formal entities and concrete syntax.  Within
  1007 the parse tree / AST representations, "constants" are decorated by
  1008 their category (class, type, const) and spelled out explicitly with
  1009 their full internal name.
  1010 
  1011 Substantial INCOMPATIBILITY concerning low-level syntax declarations
  1012 and translations (translation rules and translation functions in ML).
  1013 Some hints on upgrading:
  1014 
  1015   - Many existing uses of 'syntax' and 'translations' can be replaced
  1016     by more modern 'type_notation', 'notation' and 'abbreviation',
  1017     which are independent of this issue.
  1018 
  1019   - 'translations' require markup within the AST; the term syntax
  1020     provides the following special forms:
  1021 
  1022       CONST c   -- produces syntax version of constant c from context
  1023       XCONST c  -- literally c, checked as constant from context
  1024       c         -- literally c, if declared by 'syntax'
  1025 
  1026     Plain identifiers are treated as AST variables -- occasionally the
  1027     system indicates accidental variables via the error "rhs contains
  1028     extra variables".
  1029 
  1030     Type classes and type constructors are marked according to their
  1031     concrete syntax.  Some old translations rules need to be written
  1032     for the "type" category, using type constructor application
  1033     instead of pseudo-term application of the default category
  1034     "logic".
  1035 
  1036   - 'parse_translation' etc. in ML may use the following
  1037     antiquotations:
  1038 
  1039       @{class_syntax c}   -- type class c within parse tree / AST
  1040       @{term_syntax c}    -- type constructor c within parse tree / AST
  1041       @{const_syntax c}   -- ML version of "CONST c" above
  1042       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
  1043 
  1044   - Literal types within 'typed_print_translations', i.e. those *not*
  1045     represented as pseudo-terms are represented verbatim.  Use @{class
  1046     c} or @{type_name c} here instead of the above syntax
  1047     antiquotations.
  1048 
  1049 Note that old non-authentic syntax was based on unqualified base
  1050 names, so all of the above "constant" names would coincide.  Recall
  1051 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
  1052 diagnose syntax problems.
  1053 
  1054 * Type constructors admit general mixfix syntax, not just infix.
  1055 
  1056 * Concrete syntax may be attached to local entities without a proof
  1057 body, too.  This works via regular mixfix annotations for 'fix',
  1058 'def', 'obtain' etc. or via the explicit 'write' command, which is
  1059 similar to the 'notation' command in theory specifications.
  1060 
  1061 * Discontinued unnamed infix syntax (legacy feature for many years) --
  1062 need to specify constant name and syntax separately.  Internal ML
  1063 datatype constructors have been renamed from InfixName to Infix etc.
  1064 Minor INCOMPATIBILITY.
  1065 
  1066 * Schematic theorem statements need to be explicitly markup as such,
  1067 via commands 'schematic_lemma', 'schematic_theorem',
  1068 'schematic_corollary'.  Thus the relevance of the proof is made
  1069 syntactically clear, which impacts performance in a parallel or
  1070 asynchronous interactive environment.  Minor INCOMPATIBILITY.
  1071 
  1072 * Use of cumulative prems via "!" in some proof methods has been
  1073 discontinued (old legacy feature).
  1074 
  1075 * References 'trace_simp' and 'debug_simp' have been replaced by
  1076 configuration options stored in the context. Enabling tracing (the
  1077 case of debugging is similar) in proofs works via
  1078 
  1079   using [[trace_simp = true]]
  1080 
  1081 Tracing is then active for all invocations of the simplifier in
  1082 subsequent goal refinement steps. Tracing may also still be enabled or
  1083 disabled via the ProofGeneral settings menu.
  1084 
  1085 * Separate commands 'hide_class', 'hide_type', 'hide_const',
  1086 'hide_fact' replace the former 'hide' KIND command.  Minor
  1087 INCOMPATIBILITY.
  1088 
  1089 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
  1090 more efficient than combinations with -q1 or -q2.
  1091 
  1092 
  1093 *** Pure ***
  1094 
  1095 * Proofterms record type-class reasoning explicitly, using the
  1096 "unconstrain" operation internally.  This eliminates all sort
  1097 constraints from a theorem and proof, introducing explicit
  1098 OFCLASS-premises.  On the proof term level, this operation is
  1099 automatically applied at theorem boundaries, such that closed proofs
  1100 are always free of sort constraints.  INCOMPATIBILITY for tools that
  1101 inspect proof terms.
  1102 
  1103 * Local theory specifications may depend on extra type variables that
  1104 are not present in the result type -- arguments TYPE('a) :: 'a itself
  1105 are added internally.  For example:
  1106 
  1107   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
  1108 
  1109 * Predicates of locales introduced by classes carry a mandatory
  1110 "class" prefix.  INCOMPATIBILITY.
  1111 
  1112 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
  1113 
  1114 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
  1115 'class' instead.
  1116 
  1117 * Command 'code_reflect' allows to incorporate generated ML code into
  1118 runtime environment; replaces immature code_datatype antiquotation.
  1119 INCOMPATIBILITY.
  1120 
  1121 * Code generator: simple concept for abstract datatypes obeying
  1122 invariants.
  1123 
  1124 * Code generator: details of internal data cache have no impact on the
  1125 user space functionality any longer.
  1126 
  1127 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  1128 subgoals.  This is more appropriate for interpretations with 'where'.
  1129 INCOMPATIBILITY.
  1130 
  1131 * Command 'example_proof' opens an empty proof body.  This allows to
  1132 experiment with Isar, without producing any persistent result.
  1133 
  1134 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  1135 within a local theory context, with explicit checking of the
  1136 constructors involved (in contrast to the raw 'syntax' versions).
  1137 
  1138 * Commands 'types' and 'typedecl' now work within a local theory
  1139 context -- without introducing dependencies on parameters or
  1140 assumptions, which is not possible in Isabelle/Pure.
  1141 
  1142 * Command 'defaultsort' has been renamed to 'default_sort', it works
  1143 within a local theory context.  Minor INCOMPATIBILITY.
  1144 
  1145 
  1146 *** HOL ***
  1147 
  1148 * Command 'typedef' now works within a local theory context -- without
  1149 introducing dependencies on parameters or assumptions, which is not
  1150 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  1151 contain multiple interpretations of local typedefs (with different
  1152 non-emptiness proofs), even in a global theory context.
  1153 
  1154 * New package for quotient types.  Commands 'quotient_type' and
  1155 'quotient_definition' may be used for defining types and constants by
  1156 quotient constructions.  An example is the type of integers created by
  1157 quotienting pairs of natural numbers:
  1158 
  1159   fun
  1160     intrel :: "(nat * nat) => (nat * nat) => bool"
  1161   where
  1162     "intrel (x, y) (u, v) = (x + v = u + y)"
  1163 
  1164   quotient_type int = "nat * nat" / intrel
  1165     by (auto simp add: equivp_def expand_fun_eq)
  1166 
  1167   quotient_definition
  1168     "0::int" is "(0::nat, 0::nat)"
  1169 
  1170 The method "lifting" can be used to lift of theorems from the
  1171 underlying "raw" type to the quotient type.  The example
  1172 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  1173 construction and provides a reasoning infrastructure for finite sets.
  1174 
  1175 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  1176 clash with new theory Quotient in Main HOL.
  1177 
  1178 * Moved the SMT binding into the main HOL session, eliminating
  1179 separate HOL-SMT session.
  1180 
  1181 * List membership infix mem operation is only an input abbreviation.
  1182 INCOMPATIBILITY.
  1183 
  1184 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  1185 for future developements; former Library/Word.thy is still present in
  1186 the AFP entry RSAPPS.
  1187 
  1188 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  1189 longer shadowed.  INCOMPATIBILITY.
  1190 
  1191 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  1192 INCOMPATIBILITY.
  1193 
  1194 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  1195 INCOMPATIBILITY.
  1196 
  1197 * Dropped normalizing_semiring etc; use the facts in semiring classes
  1198 instead.  INCOMPATIBILITY.
  1199 
  1200 * Dropped several real-specific versions of lemmas about floor and
  1201 ceiling; use the generic lemmas from theory "Archimedean_Field"
  1202 instead.  INCOMPATIBILITY.
  1203 
  1204   floor_number_of_eq         ~> floor_number_of
  1205   le_floor_eq_number_of      ~> number_of_le_floor
  1206   le_floor_eq_zero           ~> zero_le_floor
  1207   le_floor_eq_one            ~> one_le_floor
  1208   floor_less_eq_number_of    ~> floor_less_number_of
  1209   floor_less_eq_zero         ~> floor_less_zero
  1210   floor_less_eq_one          ~> floor_less_one
  1211   less_floor_eq_number_of    ~> number_of_less_floor
  1212   less_floor_eq_zero         ~> zero_less_floor
  1213   less_floor_eq_one          ~> one_less_floor
  1214   floor_le_eq_number_of      ~> floor_le_number_of
  1215   floor_le_eq_zero           ~> floor_le_zero
  1216   floor_le_eq_one            ~> floor_le_one
  1217   floor_subtract_number_of   ~> floor_diff_number_of
  1218   floor_subtract_one         ~> floor_diff_one
  1219   ceiling_number_of_eq       ~> ceiling_number_of
  1220   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  1221   ceiling_le_zero_eq         ~> ceiling_le_zero
  1222   ceiling_le_eq_one          ~> ceiling_le_one
  1223   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  1224   less_ceiling_eq_zero       ~> zero_less_ceiling
  1225   less_ceiling_eq_one        ~> one_less_ceiling
  1226   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  1227   ceiling_less_eq_zero       ~> ceiling_less_zero
  1228   ceiling_less_eq_one        ~> ceiling_less_one
  1229   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  1230   le_ceiling_eq_zero         ~> zero_le_ceiling
  1231   le_ceiling_eq_one          ~> one_le_ceiling
  1232   ceiling_subtract_number_of ~> ceiling_diff_number_of
  1233   ceiling_subtract_one       ~> ceiling_diff_one
  1234 
  1235 * Theory "Finite_Set": various folding_XXX locales facilitate the
  1236 application of the various fold combinators on finite sets.
  1237 
  1238 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  1239 provides abstract red-black tree type which is backed by "RBT_Impl" as
  1240 implementation.  INCOMPATIBILTY.
  1241 
  1242 * Theory Library/Coinductive_List has been removed -- superseded by
  1243 AFP/thys/Coinductive.
  1244 
  1245 * Theory PReal, including the type "preal" and related operations, has
  1246 been removed.  INCOMPATIBILITY.
  1247 
  1248 * Real: new development using Cauchy Sequences.
  1249 
  1250 * Split off theory "Big_Operators" containing setsum, setprod,
  1251 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  1252 
  1253 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  1254 "Int" etc.  INCOMPATIBILITY.
  1255 
  1256 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  1257 
  1258 * New set of rules "ac_simps" provides combined assoc / commute
  1259 rewrites for all interpretations of the appropriate generic locales.
  1260 
  1261 * Renamed theory "OrderedGroup" to "Groups" and split theory
  1262 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  1263 appropriate and more consistent names suitable for name prefixes
  1264 within the HOL theories.  INCOMPATIBILITY.
  1265 
  1266 * Some generic constants have been put to appropriate theories:
  1267   - less_eq, less: Orderings
  1268   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  1269   - inverse, divide: Rings
  1270 INCOMPATIBILITY.
  1271 
  1272 * More consistent naming of type classes involving orderings (and
  1273 lattices):
  1274 
  1275     lower_semilattice                   ~> semilattice_inf
  1276     upper_semilattice                   ~> semilattice_sup
  1277 
  1278     dense_linear_order                  ~> dense_linorder
  1279 
  1280     pordered_ab_group_add               ~> ordered_ab_group_add
  1281     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  1282     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  1283     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  1284     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  1285     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  1286     pordered_cancel_semiring            ~> ordered_cancel_semiring
  1287     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  1288     pordered_comm_ring                  ~> ordered_comm_ring
  1289     pordered_comm_semiring              ~> ordered_comm_semiring
  1290     pordered_ring                       ~> ordered_ring
  1291     pordered_ring_abs                   ~> ordered_ring_abs
  1292     pordered_semiring                   ~> ordered_semiring
  1293 
  1294     ordered_ab_group_add                ~> linordered_ab_group_add
  1295     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  1296     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  1297     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  1298     ordered_field                       ~> linordered_field
  1299     ordered_field_no_lb                 ~> linordered_field_no_lb
  1300     ordered_field_no_ub                 ~> linordered_field_no_ub
  1301     ordered_field_dense_linear_order    ~> dense_linordered_field
  1302     ordered_idom                        ~> linordered_idom
  1303     ordered_ring                        ~> linordered_ring
  1304     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  1305     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  1306     ordered_ring_strict                 ~> linordered_ring_strict
  1307     ordered_semidom                     ~> linordered_semidom
  1308     ordered_semiring                    ~> linordered_semiring
  1309     ordered_semiring_1                  ~> linordered_semiring_1
  1310     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  1311     ordered_semiring_strict             ~> linordered_semiring_strict
  1312 
  1313   The following slightly odd type classes have been moved to a
  1314   separate theory Library/Lattice_Algebras:
  1315 
  1316     lordered_ab_group_add               ~> lattice_ab_group_add
  1317     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  1318     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  1319     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  1320     lordered_ring                       ~> lattice_ring
  1321 
  1322 INCOMPATIBILITY.
  1323 
  1324 * Refined field classes:
  1325   - classes division_ring_inverse_zero, field_inverse_zero,
  1326     linordered_field_inverse_zero include rule inverse 0 = 0 --
  1327     subsumes former division_by_zero class;
  1328   - numerous lemmas have been ported from field to division_ring.
  1329 INCOMPATIBILITY.
  1330 
  1331 * Refined algebra theorem collections:
  1332   - dropped theorem group group_simps, use algebra_simps instead;
  1333   - dropped theorem group ring_simps, use field_simps instead;
  1334   - proper theorem collection field_simps subsumes former theorem
  1335     groups field_eq_simps and field_simps;
  1336   - dropped lemma eq_minus_self_iff which is a duplicate for
  1337     equal_neg_zero.
  1338 INCOMPATIBILITY.
  1339 
  1340 * Theory Finite_Set and List: some lemmas have been generalized from
  1341 sets to lattices:
  1342 
  1343   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  1344   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  1345   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  1346   union_Union_fold_union        ~> sup_Sup_fold_sup
  1347   Inter_fold_inter              ~> Inf_fold_inf
  1348   Union_fold_union              ~> Sup_fold_sup
  1349   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  1350   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  1351   INTER_fold_inter              ~> INFI_fold_inf
  1352   UNION_fold_union              ~> SUPR_fold_sup
  1353 
  1354 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  1355 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  1356 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  1357 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  1358 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  1359 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  1360 
  1361 * Reorganized theory Multiset: swapped notation of pointwise and
  1362 multiset order:
  1363 
  1364   - pointwise ordering is instance of class order with standard syntax
  1365     <= and <;
  1366   - multiset ordering has syntax <=# and <#; partial order properties
  1367     are provided by means of interpretation with prefix
  1368     multiset_order;
  1369   - less duplication, less historical organization of sections,
  1370     conversion from associations lists to multisets, rudimentary code
  1371     generation;
  1372   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  1373     if needed.
  1374 
  1375 Renamed:
  1376 
  1377   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  1378   multi_count_ext  ~>  multiset_ext
  1379   diff_union_inverse2  ~>  diff_union_cancelR
  1380 
  1381 INCOMPATIBILITY.
  1382 
  1383 * Theory Permutation: replaced local "remove" by List.remove1.
  1384 
  1385 * Code generation: ML and OCaml code is decorated with signatures.
  1386 
  1387 * Theory List: added transpose.
  1388 
  1389 * Library/Nat_Bijection.thy is a collection of bijective functions
  1390 between nat and other types, which supersedes the older libraries
  1391 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  1392 
  1393   Constants:
  1394   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  1395   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  1396   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  1397   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  1398   Countable.pair_encode           ~> prod_encode
  1399   NatIso.prod2nat                 ~> prod_encode
  1400   NatIso.nat2prod                 ~> prod_decode
  1401   NatIso.sum2nat                  ~> sum_encode
  1402   NatIso.nat2sum                  ~> sum_decode
  1403   NatIso.list2nat                 ~> list_encode
  1404   NatIso.nat2list                 ~> list_decode
  1405   NatIso.set2nat                  ~> set_encode
  1406   NatIso.nat2set                  ~> set_decode
  1407 
  1408   Lemmas:
  1409   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  1410   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  1411   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  1412   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  1413   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  1414   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  1415   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  1416   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  1417   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  1418   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  1419   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  1420   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  1421   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  1422 
  1423 * Sledgehammer:
  1424   - Renamed ATP commands:
  1425     atp_info     ~> sledgehammer running_atps
  1426     atp_kill     ~> sledgehammer kill_atps
  1427     atp_messages ~> sledgehammer messages
  1428     atp_minimize ~> sledgehammer minimize
  1429     print_atps   ~> sledgehammer available_atps
  1430     INCOMPATIBILITY.
  1431   - Added user's manual ("isabelle doc sledgehammer").
  1432   - Added option syntax and "sledgehammer_params" to customize
  1433     Sledgehammer's behavior.  See the manual for details.
  1434   - Modified the Isar proof reconstruction code so that it produces
  1435     direct proofs rather than proofs by contradiction.  (This feature
  1436     is still experimental.)
  1437   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  1438     full-typed mode.
  1439   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  1440 
  1441 * Nitpick:
  1442   - Added and implemented "binary_ints" and "bits" options.
  1443   - Added "std" option and implemented support for nonstandard models.
  1444   - Added and implemented "finitize" option to improve the precision
  1445     of infinite datatypes based on a monotonicity analysis.
  1446   - Added support for quotient types.
  1447   - Added support for "specification" and "ax_specification"
  1448     constructs.
  1449   - Added support for local definitions (for "function" and
  1450     "termination" proofs).
  1451   - Added support for term postprocessors.
  1452   - Optimized "Multiset.multiset" and "FinFun.finfun".
  1453   - Improved efficiency of "destroy_constrs" optimization.
  1454   - Fixed soundness bugs related to "destroy_constrs" optimization and
  1455     record getters.
  1456   - Fixed soundness bug related to higher-order constructors.
  1457   - Fixed soundness bug when "full_descrs" is enabled.
  1458   - Improved precision of set constructs.
  1459   - Added "atoms" option.
  1460   - Added cache to speed up repeated Kodkod invocations on the same
  1461     problems.
  1462   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  1463     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  1464     "SAT4J_Light".  INCOMPATIBILITY.
  1465   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  1466     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  1467   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  1468 
  1469 * Method "induct" now takes instantiations of the form t, where t is not
  1470   a variable, as a shorthand for "x == t", where x is a fresh variable.
  1471   If this is not intended, t has to be enclosed in parentheses.
  1472   By default, the equalities generated by definitional instantiations
  1473   are pre-simplified, which may cause parameters of inductive cases
  1474   to disappear, or may even delete some of the inductive cases.
  1475   Use "induct (no_simp)" instead of "induct" to restore the old
  1476   behaviour. The (no_simp) option is also understood by the "cases"
  1477   and "nominal_induct" methods, which now perform pre-simplification, too.
  1478   INCOMPATIBILITY.
  1479 
  1480 
  1481 *** HOLCF ***
  1482 
  1483 * Variable names in lemmas generated by the domain package have
  1484 changed; the naming scheme is now consistent with the HOL datatype
  1485 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  1486 
  1487 * The domain package no longer defines the function "foo_copy" for
  1488 recursive domain "foo".  The reach lemma is now stated directly in
  1489 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  1490 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  1491 
  1492 * Most definedness lemmas generated by the domain package (previously
  1493 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  1494 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  1495 Proofs that used definedness lemmas as intro rules may break,
  1496 potential INCOMPATIBILITY.
  1497 
  1498 * Induction and casedist rules generated by the domain package now
  1499 declare proper case_names (one called "bottom", and one named for each
  1500 constructor).  INCOMPATIBILITY.
  1501 
  1502 * For mutually-recursive domains, separate "reach" and "take_lemma"
  1503 rules are generated for each domain, INCOMPATIBILITY.
  1504 
  1505   foo_bar.reach       ~> foo.reach  bar.reach
  1506   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  1507 
  1508 * Some lemmas generated by the domain package have been renamed for
  1509 consistency with the datatype package, INCOMPATIBILITY.
  1510 
  1511   foo.ind        ~> foo.induct
  1512   foo.finite_ind ~> foo.finite_induct
  1513   foo.coind      ~> foo.coinduct
  1514   foo.casedist   ~> foo.exhaust
  1515   foo.exhaust    ~> foo.nchotomy
  1516 
  1517 * For consistency with other definition packages, the fixrec package
  1518 now generates qualified theorem names, INCOMPATIBILITY.
  1519 
  1520   foo_simps  ~> foo.simps
  1521   foo_unfold ~> foo.unfold
  1522   foo_induct ~> foo.induct
  1523 
  1524 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  1525 method and internal fixrec proofs now use the default simpset instead.
  1526 INCOMPATIBILITY.
  1527 
  1528 * The "contlub" predicate has been removed.  Proof scripts should use
  1529 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  1530 
  1531 * The "admw" predicate has been removed, INCOMPATIBILITY.
  1532 
  1533 * The constants cpair, cfst, and csnd have been removed in favor of
  1534 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  1535 
  1536 
  1537 *** ML ***
  1538 
  1539 * Antiquotations for basic formal entities:
  1540 
  1541     @{class NAME}         -- type class
  1542     @{class_syntax NAME}  -- syntax representation of the above
  1543 
  1544     @{type_name NAME}     -- logical type
  1545     @{type_abbrev NAME}   -- type abbreviation
  1546     @{nonterminal NAME}   -- type of concrete syntactic category
  1547     @{type_syntax NAME}   -- syntax representation of any of the above
  1548 
  1549     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  1550     @{const_abbrev NAME}  -- abbreviated constant
  1551     @{const_syntax NAME}  -- syntax representation of any of the above
  1552 
  1553 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  1554 syntax constant (cf. 'syntax' command).
  1555 
  1556 * Antiquotation @{make_string} inlines a function to print arbitrary
  1557 values similar to the ML toplevel.  The result is compiler dependent
  1558 and may fall back on "?" in certain situations.
  1559 
  1560 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  1561 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  1562 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  1563 not work with the asynchronous Isar document model.
  1564 
  1565 * Configuration options now admit dynamic default values, depending on
  1566 the context or even global references.
  1567 
  1568 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  1569 uses an efficient external library if available (for Poly/ML).
  1570 
  1571 * Renamed some important ML structures, while keeping the old names
  1572 for some time as aliases within the structure Legacy:
  1573 
  1574   OuterKeyword  ~>  Keyword
  1575   OuterLex      ~>  Token
  1576   OuterParse    ~>  Parse
  1577   OuterSyntax   ~>  Outer_Syntax
  1578   PrintMode     ~>  Print_Mode
  1579   SpecParse     ~>  Parse_Spec
  1580   ThyInfo       ~>  Thy_Info
  1581   ThyLoad       ~>  Thy_Load
  1582   ThyOutput     ~>  Thy_Output
  1583   TypeInfer     ~>  Type_Infer
  1584 
  1585 Note that "open Legacy" simplifies porting of sources, but forgetting
  1586 to remove it again will complicate porting again in the future.
  1587 
  1588 * Most operations that refer to a global context are named
  1589 accordingly, e.g. Simplifier.global_context or
  1590 ProofContext.init_global.  There are some situations where a global
  1591 context actually works, but under normal circumstances one needs to
  1592 pass the proper local context through the code!
  1593 
  1594 * Discontinued old TheoryDataFun with its copy/init operation -- data
  1595 needs to be pure.  Functor Theory_Data_PP retains the traditional
  1596 Pretty.pp argument to merge, which is absent in the standard
  1597 Theory_Data version.
  1598 
  1599 * Sorts.certify_sort and derived "cert" operations for types and terms
  1600 no longer minimize sorts.  Thus certification at the boundary of the
  1601 inference kernel becomes invariant under addition of class relations,
  1602 which is an important monotonicity principle.  Sorts are now minimized
  1603 in the syntax layer only, at the boundary between the end-user and the
  1604 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  1605 explicitly in rare situations.
  1606 
  1607 * Renamed old-style Drule.standard to Drule.export_without_context, to
  1608 emphasize that this is in no way a standard operation.
  1609 INCOMPATIBILITY.
  1610 
  1611 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  1612 usual for resolution.  Rare INCOMPATIBILITY.
  1613 
  1614 * Renamed varify/unvarify operations to varify_global/unvarify_global
  1615 to emphasize that these only work in a global situation (which is
  1616 quite rare).
  1617 
  1618 * Curried take and drop in library.ML; negative length is interpreted
  1619 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  1620 
  1621 * Proof terms: type substitutions on proof constants now use canonical
  1622 order of type variables.  INCOMPATIBILITY for tools working with proof
  1623 terms.
  1624 
  1625 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  1626 may no longer carry premises.  User-level specifications are
  1627 transformed accordingly by Thm.add_axiom/add_def.
  1628 
  1629 
  1630 *** System ***
  1631 
  1632 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  1633 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  1634 proof terms are enabled unconditionally in the new HOL-Proofs image.
  1635 
  1636 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  1637 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  1638 respectively.
  1639 
  1640 * Old lib/scripts/polyml-platform is superseded by the
  1641 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  1642 variant, even on a 64 bit machine.  The following example setting
  1643 prefers 64 bit if available:
  1644 
  1645   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  1646 
  1647 * The preliminary Isabelle/jEdit application demonstrates the emerging
  1648 Isabelle/Scala layer for advanced prover interaction and integration.
  1649 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  1650 component.
  1651 
  1652 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  1653 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  1654 similar to the default assignment of the document preparation system
  1655 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  1656 provides some operations for direct access to the font without asking
  1657 the user for manual installation.
  1658 
  1659 
  1660 
  1661 New in Isabelle2009-1 (December 2009)
  1662 -------------------------------------
  1663 
  1664 *** General ***
  1665 
  1666 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  1667 one backslash should be used, even in ML sources.
  1668 
  1669 
  1670 *** Pure ***
  1671 
  1672 * Locale interpretation propagates mixins along the locale hierarchy.
  1673 The currently only available mixins are the equations used to map
  1674 local definitions to terms of the target domain of an interpretation.
  1675 
  1676 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  1677 loc" to print all interpretations of locale "loc" in the theory.
  1678 Interpretations in proofs are not shown.
  1679 
  1680 * Thoroughly revised locales tutorial.  New section on conditional
  1681 interpretation.
  1682 
  1683 * On instantiation of classes, remaining undefined class parameters
  1684 are formally declared.  INCOMPATIBILITY.
  1685 
  1686 
  1687 *** Document preparation ***
  1688 
  1689 * New generalized style concept for printing terms: @{foo (style) ...}
  1690 instead of @{foo_style style ...}  (old form is still retained for
  1691 backward compatibility).  Styles can be also applied for
  1692 antiquotations prop, term_type and typeof.
  1693 
  1694 
  1695 *** HOL ***
  1696 
  1697 * New proof method "smt" for a combination of first-order logic with
  1698 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  1699 fixed-size bitvectors; there is also basic support for higher-order
  1700 features (esp. lambda abstractions).  It is an incomplete decision
  1701 procedure based on external SMT solvers using the oracle mechanism;
  1702 for the SMT solver Z3, this method is proof-producing.  Certificates
  1703 are provided to avoid calling the external solvers solely for
  1704 re-checking proofs.  Due to a remote SMT service there is no need for
  1705 installing SMT solvers locally.  See src/HOL/SMT.
  1706 
  1707 * New commands to load and prove verification conditions generated by
  1708 the Boogie program verifier or derived systems (e.g. the Verifying C
  1709 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1710 
  1711 * New counterexample generator tool 'nitpick' based on the Kodkod
  1712 relational model finder.  See src/HOL/Tools/Nitpick and
  1713 src/HOL/Nitpick_Examples.
  1714 
  1715 * New commands 'code_pred' and 'values' to invoke the predicate
  1716 compiler and to enumerate values of inductive predicates.
  1717 
  1718 * A tabled implementation of the reflexive transitive closure.
  1719 
  1720 * New implementation of quickcheck uses generic code generator;
  1721 default generators are provided for all suitable HOL types, records
  1722 and datatypes.  Old quickcheck can be re-activated importing theory
  1723 Library/SML_Quickcheck.
  1724 
  1725 * New testing tool Mirabelle for automated proof tools.  Applies
  1726 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1727 every proof step in a theory.  To be used in batch mode via the
  1728 "mirabelle" utility.
  1729 
  1730 * New proof method "sos" (sum of squares) for nonlinear real
  1731 arithmetic (originally due to John Harison). It requires theory
  1732 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1733 works well in practice on quantifier-free real arithmetic with +, -,
  1734 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1735 inequalities between polynomials.  It makes use of external
  1736 semidefinite programming solvers.  Method "sos" generates a
  1737 certificate that can be pasted into the proof thus avoiding the need
  1738 to call an external tool every time the proof is checked.  See
  1739 src/HOL/Library/Sum_Of_Squares.
  1740 
  1741 * New method "linarith" invokes existing linear arithmetic decision
  1742 procedure only.
  1743 
  1744 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1745 
  1746 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1747 Causes full type information to be output to the ATPs.  This slows
  1748 ATPs down considerably but eliminates a source of unsound "proofs"
  1749 that fail later.
  1750 
  1751 * New method "metisFT": A version of metis that uses full type
  1752 information in order to avoid failures of proof reconstruction.
  1753 
  1754 * New evaluator "approximate" approximates an real valued term using
  1755 the same method as the approximation method.
  1756 
  1757 * Method "approximate" now supports arithmetic expressions as
  1758 boundaries of intervals and implements interval splitting and Taylor
  1759 series expansion.
  1760 
  1761 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1762 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1763 
  1764 * New theory SupInf of the supremum and infimum operators for sets of
  1765 reals.
  1766 
  1767 * New theory Probability, which contains a development of measure
  1768 theory, eventually leading to Lebesgue integration and probability.
  1769 
  1770 * Extended Multivariate Analysis to include derivation and Brouwer's
  1771 fixpoint theorem.
  1772 
  1773 * Reorganization of number theory, INCOMPATIBILITY:
  1774   - new number theory development for nat and int, in theories Divides
  1775     and GCD as well as in new session Number_Theory
  1776   - some constants and facts now suffixed with _nat and _int
  1777     accordingly
  1778   - former session NumberTheory now named Old_Number_Theory, including
  1779     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1780   - moved theory Pocklington from src/HOL/Library to
  1781     src/HOL/Old_Number_Theory
  1782 
  1783 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1784 lcm of finite and infinite sets. It is shown that they form a complete
  1785 lattice.
  1786 
  1787 * Class semiring_div requires superclass no_zero_divisors and proof of
  1788 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1789 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1790 generalized to class semiring_div, subsuming former theorems
  1791 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1792 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1793 INCOMPATIBILITY.
  1794 
  1795 * Refinements to lattice classes and sets:
  1796   - less default intro/elim rules in locale variant, more default
  1797     intro/elim rules in class variant: more uniformity
  1798   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1799     le_inf_iff
  1800   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1801     sup_aci)
  1802   - renamed ACI to inf_sup_aci
  1803   - new class "boolean_algebra"
  1804   - class "complete_lattice" moved to separate theory
  1805     "Complete_Lattice"; corresponding constants (and abbreviations)
  1806     renamed and with authentic syntax:
  1807     Set.Inf ~>    Complete_Lattice.Inf
  1808     Set.Sup ~>    Complete_Lattice.Sup
  1809     Set.INFI ~>   Complete_Lattice.INFI
  1810     Set.SUPR ~>   Complete_Lattice.SUPR
  1811     Set.Inter ~>  Complete_Lattice.Inter
  1812     Set.Union ~>  Complete_Lattice.Union
  1813     Set.INTER ~>  Complete_Lattice.INTER
  1814     Set.UNION ~>  Complete_Lattice.UNION
  1815   - authentic syntax for
  1816     Set.Pow
  1817     Set.image
  1818   - mere abbreviations:
  1819     Set.empty               (for bot)
  1820     Set.UNIV                (for top)
  1821     Set.inter               (for inf, formerly Set.Int)
  1822     Set.union               (for sup, formerly Set.Un)
  1823     Complete_Lattice.Inter  (for Inf)
  1824     Complete_Lattice.Union  (for Sup)
  1825     Complete_Lattice.INTER  (for INFI)
  1826     Complete_Lattice.UNION  (for SUPR)
  1827   - object-logic definitions as far as appropriate
  1828 
  1829 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1830 Un_subset_iff are explicitly deleted as default simp rules; then also
  1831 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1832 deleted to achieve the desired effect.
  1833 
  1834 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1835 rules by default any longer; the same applies to min_max.inf_absorb1
  1836 etc.  INCOMPATIBILITY.
  1837 
  1838 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1839 pred_set_conv by default.  INCOMPATIBILITY.
  1840 
  1841 * Power operations on relations and functions are now one dedicated
  1842 constant "compow" with infix syntax "^^".  Power operation on
  1843 multiplicative monoids retains syntax "^" and is now defined generic
  1844 in class power.  INCOMPATIBILITY.
  1845 
  1846 * Relation composition "R O S" now has a more standard argument order:
  1847 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1848 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1849 break, since the O_assoc rule was not rewritten like this.  Fix using
  1850 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1851 
  1852 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1853 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1854 INCOMPATIBILITY.
  1855 
  1856 * Most rules produced by inductive and datatype package have mandatory
  1857 prefixes.  INCOMPATIBILITY.
  1858 
  1859 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1860 the attribute of the same name.  Each of the theorems in the list
  1861 DERIV_intros assumes composition with an additional function and
  1862 matches a variable to the derivative, which has to be solved by the
  1863 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1864 of most elementary terms.  Former Maclauren.DERIV_tac and
  1865 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1866 INCOMPATIBILITY.
  1867 
  1868 * Code generator attributes follow the usual underscore convention:
  1869     code_unfold     replaces    code unfold
  1870     code_post       replaces    code post
  1871     etc.
  1872   INCOMPATIBILITY.
  1873 
  1874 * Renamed methods:
  1875     sizechange -> size_change
  1876     induct_scheme -> induction_schema
  1877   INCOMPATIBILITY.
  1878 
  1879 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1880 INCOMPATIBILITY, use "undefined" directly.
  1881 
  1882 * Renamed theorems:
  1883     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1884     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1885     Suc_plus1 -> Suc_eq_plus1
  1886     *anti_sym -> *antisym*
  1887     vector_less_eq_def -> vector_le_def
  1888   INCOMPATIBILITY.
  1889 
  1890 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1891 INCOMPATIBILITY.
  1892 
  1893 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1894 INCOMPATIBILITY.
  1895 
  1896 
  1897 *** HOLCF ***
  1898 
  1899 * Theory Representable defines a class "rep" of domains that are
  1900 representable (via an ep-pair) in the universal domain type "udom".
  1901 Instances are provided for all type constructors defined in HOLCF.
  1902 
  1903 * The 'new_domain' command is a purely definitional version of the
  1904 domain package, for representable domains.  Syntax is identical to the
  1905 old domain package.  The 'new_domain' package also supports indirect
  1906 recursion using previously-defined type constructors.  See
  1907 src/HOLCF/ex/New_Domain.thy for examples.
  1908 
  1909 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1910 on the left-hand side of an equation, and then performs
  1911 simplification.  Rewriting is done using rules declared with the
  1912 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1913 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1914 
  1915 * The pattern-match compiler in 'fixrec' can now handle constructors
  1916 with HOL function types.  Pattern-match combinators for the Pair
  1917 constructor are pre-configured.
  1918 
  1919 * The 'fixrec' package now produces better fixed-point induction rules
  1920 for mutually-recursive definitions:  Induction rules have conclusions
  1921 of the form "P foo bar" instead of "P <foo, bar>".
  1922 
  1923 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1924 been renamed to "below".  The name "below" now replaces "less" in many
  1925 theorem names.  (Legacy theorem names using "less" are still supported
  1926 as well.)
  1927 
  1928 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1929 patterns can be used to generate strictness rules, or to make
  1930 functions more strict (much like the bang-patterns supported by the
  1931 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1932 examples.
  1933 
  1934 
  1935 *** ML ***
  1936 
  1937 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1938 errors and run-time exceptions, including detailed source positions.
  1939 
  1940 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1941 identified entries, with some additional information such as source
  1942 position, logical grouping etc.
  1943 
  1944 * Theory and context data is now introduced by the simplified and
  1945 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1946 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1947 copy operation) is still available for some time.
  1948 
  1949 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1950 provides a high-level programming interface to synchronized state
  1951 variables with atomic update.  This works via pure function
  1952 application within a critical section -- its runtime should be as
  1953 short as possible; beware of deadlocks if critical code is nested,
  1954 either directly or indirectly via other synchronized variables!
  1955 
  1956 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1957 wraps raw ML references, explicitly indicating their non-thread-safe
  1958 behaviour.  The Isar toplevel keeps this structure open, to
  1959 accommodate Proof General as well as quick and dirty interactive
  1960 experiments with references.
  1961 
  1962 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1963 parallel tactical reasoning.
  1964 
  1965 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1966 are similar to SUBPROOF, but are slightly more flexible: only the
  1967 specified parts of the subgoal are imported into the context, and the
  1968 body tactic may introduce new subgoals and schematic variables.
  1969 
  1970 * Old tactical METAHYPS, which does not observe the proof context, has
  1971 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1972 or Subgoal.FOCUS etc.
  1973 
  1974 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  1975 functors have their own ML name space there is no point to mark them
  1976 separately.)  Minor INCOMPATIBILITY.
  1977 
  1978 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  1979 
  1980 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  1981 INCOMPATIBILITY.
  1982 
  1983 * Operations of structure Skip_Proof no longer require quick_and_dirty
  1984 mode, which avoids critical setmp.
  1985 
  1986 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  1987 combinators for "args".  INCOMPATIBILITY, need to use simplified
  1988 Attrib/Method.setup introduced in Isabelle2009.
  1989 
  1990 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  1991 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  1992 last resort.  INCOMPATIBILITY.
  1993 
  1994 * Display.pretty_thm now requires a proper context (cf. former
  1995 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  1996 or even Display.pretty_thm_without_context as last resort.
  1997 INCOMPATIBILITY.
  1998 
  1999 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  2000 Syntax.pretty_typ/term directly, preferably with proper context
  2001 instead of global theory.
  2002 
  2003 
  2004 *** System ***
  2005 
  2006 * Further fine tuning of parallel proof checking, scales up to 8 cores
  2007 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  2008 usedir option -q.
  2009 
  2010 * Support for additional "Isabelle components" via etc/components, see
  2011 also the system manual.
  2012 
  2013 * The isabelle makeall tool now operates on all components with
  2014 IsaMakefile, not just hardwired "logics".
  2015 
  2016 * Removed "compress" option from isabelle-process and isabelle usedir;
  2017 this is always enabled.
  2018 
  2019 * Discontinued support for Poly/ML 4.x versions.
  2020 
  2021 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  2022 on a given logic image.  This requires the lighttpd webserver and is
  2023 currently supported on Linux only.
  2024 
  2025 
  2026 
  2027 New in Isabelle2009 (April 2009)
  2028 --------------------------------
  2029 
  2030 *** General ***
  2031 
  2032 * Simplified main Isabelle executables, with less surprises on
  2033 case-insensitive file-systems (such as Mac OS).
  2034 
  2035   - The main Isabelle tool wrapper is now called "isabelle" instead of
  2036     "isatool."
  2037 
  2038   - The former "isabelle" alias for "isabelle-process" has been
  2039     removed (should rarely occur to regular users).
  2040 
  2041   - The former "isabelle-interface" and its alias "Isabelle" have been
  2042     removed (interfaces are now regular Isabelle tools).
  2043 
  2044 Within scripts and make files, the Isabelle environment variables
  2045 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  2046 respectively.  (The latter are still available as legacy feature.)
  2047 
  2048 The old isabelle-interface wrapper could react in confusing ways if
  2049 the interface was uninstalled or changed otherwise.  Individual
  2050 interface tool configuration is now more explicit, see also the
  2051 Isabelle system manual.  In particular, Proof General is now available
  2052 via "isabelle emacs".
  2053 
  2054 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  2055 purge installed copies of Isabelle executables and re-run "isabelle
  2056 install -p ...", or use symlinks.
  2057 
  2058 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  2059 old ~/isabelle, which was slightly non-standard and apt to cause
  2060 surprises on case-insensitive file-systems (such as Mac OS).
  2061 
  2062 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  2063 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  2064 care is required when using older releases of Isabelle.  Note that
  2065 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  2066 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  2067 
  2068 * Proofs of fully specified statements are run in parallel on
  2069 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  2070 a regular 4-core machine, if the initial heap space is made reasonably
  2071 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  2072 
  2073 * The main reference manuals ("isar-ref", "implementation", and
  2074 "system") have been updated and extended.  Formally checked references
  2075 as hyperlinks are now available uniformly.
  2076 
  2077 
  2078 *** Pure ***
  2079 
  2080 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  2081 respects.  The most important changes are listed below.  See the
  2082 Tutorial on Locales ("locales" manual) for details.
  2083 
  2084 - In locale expressions, instantiation replaces renaming.  Parameters
  2085 must be declared in a for clause.  To aid compatibility with previous
  2086 parameter inheritance, in locale declarations, parameters that are not
  2087 'touched' (instantiation position "_" or omitted) are implicitly added
  2088 with their syntax at the beginning of the for clause.
  2089 
  2090 - Syntax from abbreviations and definitions in locales is available in
  2091 locale expressions and context elements.  The latter is particularly
  2092 useful in locale declarations.
  2093 
  2094 - More flexible mechanisms to qualify names generated by locale
  2095 expressions.  Qualifiers (prefixes) may be specified in locale
  2096 expressions, and can be marked as mandatory (syntax: "name!:") or
  2097 optional (syntax "name?:").  The default depends for plain "name:"
  2098 depends on the situation where a locale expression is used: in
  2099 commands 'locale' and 'sublocale' prefixes are optional, in
  2100 'interpretation' and 'interpret' prefixes are mandatory.  The old
  2101 implicit qualifiers derived from the parameter names of a locale are
  2102 no longer generated.
  2103 
  2104 - Command "sublocale l < e" replaces "interpretation l < e".  The
  2105 instantiation clause in "interpretation" and "interpret" (square
  2106 brackets) is no longer available.  Use locale expressions.
  2107 
  2108 - When converting proof scripts, mandatory qualifiers in
  2109 'interpretation' and 'interpret' should be retained by default, even
  2110 if this is an INCOMPATIBILITY compared to former behavior.  In the
  2111 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  2112 in locale expressions range over a single locale instance only.
  2113 
  2114 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  2115 In existing theorem specifications replace the includes element by the
  2116 respective context elements of the included locale, omitting those
  2117 that are already present in the theorem specification.  Multiple
  2118 assume elements of a locale should be replaced by a single one
  2119 involving the locale predicate.  In the proof body, declarations (most
  2120 notably theorems) may be regained by interpreting the respective
  2121 locales in the proof context as required (command "interpret").
  2122 
  2123 If using "includes" in replacement of a target solely because the
  2124 parameter types in the theorem are not as general as in the target,
  2125 consider declaring a new locale with additional type constraints on
  2126 the parameters (context element "constrains").
  2127 
  2128 - Discontinued "locale (open)".  INCOMPATIBILITY.
  2129 
  2130 - Locale interpretation commands no longer attempt to simplify goal.
  2131 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  2132 methods intro_locales and unfold_locales to clarify.
  2133 
  2134 - Locale interpretation commands no longer accept interpretation
  2135 attributes.  INCOMPATIBILITY.
  2136 
  2137 * Class declaration: so-called "base sort" must not be given in import
  2138 list any longer, but is inferred from the specification.  Particularly
  2139 in HOL, write
  2140 
  2141     class foo = ...
  2142 
  2143 instead of
  2144 
  2145     class foo = type + ...
  2146 
  2147 * Class target: global versions of theorems stemming do not carry a
  2148 parameter prefix any longer.  INCOMPATIBILITY.
  2149 
  2150 * Class 'instance' command no longer accepts attached definitions.
  2151 INCOMPATIBILITY, use proper 'instantiation' target instead.
  2152 
  2153 * Recovered hiding of consts, which was accidentally broken in
  2154 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  2155 makes c inaccessible; consider using ``hide (open) const c'' instead.
  2156 
  2157 * Slightly more coherent Pure syntax, with updated documentation in
  2158 isar-ref manual.  Removed locales meta_term_syntax and
  2159 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  2160 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  2161 directly in regular applications.
  2162 
  2163 * There is a new syntactic category "float_const" for signed decimal
  2164 fractions (e.g. 123.45 or -123.45).
  2165 
  2166 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  2167 interface with 'setup' command instead.
  2168 
  2169 * Command 'local_setup' is similar to 'setup', but operates on a local
  2170 theory context.
  2171 
  2172 * The 'axiomatization' command now only works within a global theory
  2173 context.  INCOMPATIBILITY.
  2174 
  2175 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  2176 hypotheses.  Sorts required in the course of reasoning need to be
  2177 covered by the constraints in the initial statement, completed by the
  2178 type instance information of the background theory.  Non-trivial sort
  2179 hypotheses, which rarely occur in practice, may be specified via
  2180 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  2181 
  2182   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  2183 
  2184 The result contains an implicit sort hypotheses as before --
  2185 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  2186 normalization.
  2187 
  2188 * Generalized Isar history, with support for linear undo, direct state
  2189 addressing etc.
  2190 
  2191 * Changed defaults for unify configuration options:
  2192 
  2193   unify_trace_bound = 50 (formerly 25)
  2194   unify_search_bound = 60 (formerly 30)
  2195 
  2196 * Different bookkeeping for code equations (INCOMPATIBILITY):
  2197 
  2198   a) On theory merge, the last set of code equations for a particular
  2199      constant is taken (in accordance with the policy applied by other
  2200      parts of the code generator framework).
  2201 
  2202   b) Code equations stemming from explicit declarations (e.g. code
  2203      attribute) gain priority over default code equations stemming
  2204      from definition, primrec, fun etc.
  2205 
  2206 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  2207 
  2208 * Unified theorem tables for both code generators.  Thus [code
  2209 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  2210 
  2211 * Command 'find_consts' searches for constants based on type and name
  2212 patterns, e.g.
  2213 
  2214     find_consts "_ => bool"
  2215 
  2216 By default, matching is against subtypes, but it may be restricted to
  2217 the whole type.  Searching by name is possible.  Multiple queries are
  2218 conjunctive and queries may be negated by prefixing them with a
  2219 hyphen:
  2220 
  2221     find_consts strict: "_ => bool" name: "Int" -"int => int"
  2222 
  2223 * New 'find_theorems' criterion "solves" matches theorems that
  2224 directly solve the current goal (modulo higher-order unification).
  2225 
  2226 * Auto solve feature for main theorem statements: whenever a new goal
  2227 is stated, "find_theorems solves" is called; any theorems that could
  2228 solve the lemma directly are listed as part of the goal state.
  2229 Cf. associated options in Proof General Isabelle settings menu,
  2230 enabled by default, with reasonable timeout for pathological cases of
  2231 higher-order unification.
  2232 
  2233 
  2234 *** Document preparation ***
  2235 
  2236 * Antiquotation @{lemma} now imitates a regular terminal proof,
  2237 demanding keyword 'by' and supporting the full method expression
  2238 syntax just like the Isar command 'by'.
  2239 
  2240 
  2241 *** HOL ***
  2242 
  2243 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  2244 points Main and Complex_Main remain as before.
  2245 
  2246 * Logic image HOL-Plain provides a minimal HOL with the most important
  2247 tools available (inductive, datatype, primrec, ...).  This facilitates
  2248 experimentation and tool development.  Note that user applications
  2249 (and library theories) should never refer to anything below theory
  2250 Main, as before.
  2251 
  2252 * Logic image HOL-Main stops at theory Main, and thus facilitates
  2253 experimentation due to shorter build times.
  2254 
  2255 * Logic image HOL-NSA contains theories of nonstandard analysis which
  2256 were previously part of former HOL-Complex.  Entry point Hyperreal
  2257 remains valid, but theories formerly using Complex_Main should now use
  2258 new entry point Hypercomplex.
  2259 
  2260 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  2261 Posix processes.  Avoids potentially expensive forking of the ML
  2262 process.  New thread-based implementation also works on non-Unix
  2263 platforms (Cygwin).  Provers are no longer hardwired, but defined
  2264 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  2265 commands are covered in the isar-ref manual.
  2266 
  2267 * Wrapper scripts for remote SystemOnTPTP service allows to use
  2268 sledgehammer without local ATP installation (Vampire etc.). Other
  2269 provers may be included via suitable ML wrappers, see also
  2270 src/HOL/ATP_Linkup.thy.
  2271 
  2272 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  2273 menu.
  2274 
  2275 * The metis method no longer fails because the theorem is too trivial
  2276 (contains the empty clause).
  2277 
  2278 * The metis method now fails in the usual manner, rather than raising
  2279 an exception, if it determines that it cannot prove the theorem.
  2280 
  2281 * Method "coherent" implements a prover for coherent logic (see also
  2282 src/Tools/coherent.ML).
  2283 
  2284 * Constants "undefined" and "default" replace "arbitrary".  Usually
  2285 "undefined" is the right choice to replace "arbitrary", though
  2286 logically there is no difference.  INCOMPATIBILITY.
  2287 
  2288 * Command "value" now integrates different evaluation mechanisms.  The
  2289 result of the first successful evaluation mechanism is printed.  In
  2290 square brackets a particular named evaluation mechanisms may be
  2291 specified (currently, [SML], [code] or [nbe]).  See further
  2292 src/HOL/ex/Eval_Examples.thy.
  2293 
  2294 * Normalization by evaluation now allows non-leftlinear equations.
  2295 Declare with attribute [code nbe].
  2296 
  2297 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  2298 as the structured Isar versions "cases" and "induct", cf. the
  2299 corresponding "cases" and "induct" attributes.  Mutual induction rules
  2300 are now presented as a list of individual projections
  2301 (e.g. foo_bar.inducts for types foo and bar); the old format with
  2302 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  2303 rare situations a different rule is selected --- notably nested tuple
  2304 elimination instead of former prod.exhaust: use explicit (case_tac t
  2305 rule: prod.exhaust) here.
  2306 
  2307 * Attributes "cases", "induct", "coinduct" support "del" option.
  2308 
  2309 * Removed fact "case_split_thm", which duplicates "case_split".
  2310 
  2311 * The option datatype has been moved to a new theory Option.  Renamed
  2312 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  2313 
  2314 * New predicate "strict_mono" classifies strict functions on partial
  2315 orders.  With strict functions on linear orders, reasoning about
  2316 (in)equalities is facilitated by theorems "strict_mono_eq",
  2317 "strict_mono_less_eq" and "strict_mono_less".
  2318 
  2319 * Some set operations are now proper qualified constants with
  2320 authentic syntax.  INCOMPATIBILITY:
  2321 
  2322     op Int ~>   Set.Int
  2323     op Un ~>    Set.Un
  2324     INTER ~>    Set.INTER
  2325     UNION ~>    Set.UNION
  2326     Inter ~>    Set.Inter
  2327     Union ~>    Set.Union
  2328     {} ~>       Set.empty
  2329     UNIV ~>     Set.UNIV
  2330 
  2331 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  2332 theory Set.
  2333 
  2334 * Auxiliary class "itself" has disappeared -- classes without any
  2335 parameter are treated as expected by the 'class' command.
  2336 
  2337 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  2338 
  2339 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  2340 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  2341 
  2342 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  2343 method "approximation".  It proves formulas on real values by using
  2344 interval arithmetic.  In the formulas are also the transcendental
  2345 functions sin, cos, tan, atan, ln, exp and the constant pi are
  2346 allowed. For examples see
  2347 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  2348 
  2349 * Theory "Reflection" now resides in HOL/Library.
  2350 
  2351 * Entry point to Word library now simply named "Word".
  2352 INCOMPATIBILITY.
  2353 
  2354 * Made source layout more coherent with logical distribution
  2355 structure:
  2356 
  2357     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  2358     src/HOL/Library/Code_Message.thy ~> src/HOL/
  2359     src/HOL/Library/GCD.thy ~> src/HOL/
  2360     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  2361     src/HOL/Library/Parity.thy ~> src/HOL/
  2362     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  2363     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  2364     src/HOL/Real/Lubs.thy ~> src/HOL/
  2365     src/HOL/Real/PReal.thy ~> src/HOL/
  2366     src/HOL/Real/Rational.thy ~> src/HOL/
  2367     src/HOL/Real/RComplete.thy ~> src/HOL/
  2368     src/HOL/Real/RealDef.thy ~> src/HOL/
  2369     src/HOL/Real/RealPow.thy ~> src/HOL/
  2370     src/HOL/Real/Real.thy ~> src/HOL/
  2371     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  2372     src/HOL/Complex/Complex.thy ~> src/HOL/
  2373     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  2374     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  2375     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  2376     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  2377     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  2378     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  2379     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  2380     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  2381     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  2382     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  2383     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  2384     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  2385     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  2386     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  2387     src/HOL/Real/Float ~> src/HOL/Library/
  2388     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  2389     src/HOL/Real/RealVector.thy ~> src/HOL/
  2390 
  2391     src/HOL/arith_data.ML ~> src/HOL/Tools
  2392     src/HOL/hologic.ML ~> src/HOL/Tools
  2393     src/HOL/simpdata.ML ~> src/HOL/Tools
  2394     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  2395     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  2396     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  2397     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  2398     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  2399     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  2400     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  2401 
  2402     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  2403     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  2404     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  2405     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  2406     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  2407     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  2408 
  2409 * If methods "eval" and "evaluation" encounter a structured proof
  2410 state with !!/==>, only the conclusion is evaluated to True (if
  2411 possible), avoiding strange error messages.
  2412 
  2413 * Method "sizechange" automates termination proofs using (a
  2414 modification of) the size-change principle.  Requires SAT solver.  See
  2415 src/HOL/ex/Termination.thy for examples.
  2416 
  2417 * Simplifier: simproc for let expressions now unfolds if bound
  2418 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  2419 
  2420 * Method "arith": Linear arithmetic now ignores all inequalities when
  2421 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  2422 
  2423 * New attribute "arith" for facts that should always be used
  2424 automatically by arithmetic. It is intended to be used locally in
  2425 proofs, e.g.
  2426 
  2427   assumes [arith]: "x > 0"
  2428 
  2429 Global usage is discouraged because of possible performance impact.
  2430 
  2431 * New classes "top" and "bot" with corresponding operations "top" and
  2432 "bot" in theory Orderings; instantiation of class "complete_lattice"
  2433 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  2434 
  2435 * Changed definition lemma "less_fun_def" in order to provide an
  2436 instance for preorders on functions; use lemma "less_le" instead.
  2437 INCOMPATIBILITY.
  2438 
  2439 * Theory Orderings: class "wellorder" moved here, with explicit
  2440 induction rule "less_induct" as assumption.  For instantiation of
  2441 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  2442 INCOMPATIBILITY.
  2443 
  2444 * Theory Orderings: added class "preorder" as superclass of "order".
  2445 INCOMPATIBILITY: Instantiation proofs for order, linorder
  2446 etc. slightly changed.  Some theorems named order_class.* now named
  2447 preorder_class.*.
  2448 
  2449 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  2450 "diag" to "Id_on".
  2451 
  2452 * Theory Finite_Set: added a new fold combinator of type
  2453 
  2454   ('a => 'b => 'b) => 'b => 'a set => 'b
  2455 
  2456 Occasionally this is more convenient than the old fold combinator
  2457 which is now defined in terms of the new one and renamed to
  2458 fold_image.
  2459 
  2460 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  2461 and "ring_simps" have been replaced by "algebra_simps" (which can be
  2462 extended with further lemmas!).  At the moment both still exist but
  2463 the former will disappear at some point.
  2464 
  2465 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  2466 class recpower.  Type-specific simp rules for various recpower types
  2467 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  2468 
  2469 rat_power_0    -> power_0
  2470 rat_power_Suc  -> power_Suc
  2471 realpow_0      -> power_0
  2472 realpow_Suc    -> power_Suc
  2473 complexpow_0   -> power_0
  2474 complexpow_Suc -> power_Suc
  2475 power_poly_0   -> power_0
  2476 power_poly_Suc -> power_Suc
  2477 
  2478 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  2479 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  2480 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  2481 of lemmas from Divides has been generalized from nat to class
  2482 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  2483 renames resulting from duplicate elimination:
  2484 
  2485     dvd_def_mod ~>          dvd_eq_mod_eq_0
  2486     zero_dvd_iff ~>         dvd_0_left_iff
  2487     dvd_0 ~>                dvd_0_right
  2488     DIVISION_BY_ZERO_DIV ~> div_by_0
  2489     DIVISION_BY_ZERO_MOD ~> mod_by_0
  2490     mult_div ~>             div_mult_self2_is_id
  2491     mult_mod ~>             mod_mult_self2_is_0
  2492 
  2493 * Theory IntDiv: removed many lemmas that are instances of class-based
  2494 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  2495 rename old lemmas as follows:
  2496 
  2497 dvd_diff               -> nat_dvd_diff
  2498 dvd_zminus_iff         -> dvd_minus_iff
  2499 mod_add1_eq            -> mod_add_eq
  2500 mod_mult1_eq           -> mod_mult_right_eq
  2501 mod_mult1_eq'          -> mod_mult_left_eq
  2502 mod_mult_distrib_mod   -> mod_mult_eq
  2503 nat_mod_add_left_eq    -> mod_add_left_eq
  2504 nat_mod_add_right_eq   -> mod_add_right_eq
  2505 nat_mod_div_trivial    -> mod_div_trivial
  2506 nat_mod_mod_trivial    -> mod_mod_trivial
  2507 zdiv_zadd_self1        -> div_add_self1
  2508 zdiv_zadd_self2        -> div_add_self2
  2509 zdiv_zmult_self1       -> div_mult_self2_is_id
  2510 zdiv_zmult_self2       -> div_mult_self1_is_id
  2511 zdvd_triv_left         -> dvd_triv_left
  2512 zdvd_triv_right        -> dvd_triv_right
  2513 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  2514 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  2515 zmod_zadd_left_eq      -> mod_add_left_eq
  2516 zmod_zadd_right_eq     -> mod_add_right_eq
  2517 zmod_zadd_self1        -> mod_add_self1
  2518 zmod_zadd_self2        -> mod_add_self2
  2519 zmod_zadd1_eq          -> mod_add_eq
  2520 zmod_zdiff1_eq         -> mod_diff_eq
  2521 zmod_zdvd_zmod         -> mod_mod_cancel
  2522 zmod_zmod_cancel       -> mod_mod_cancel
  2523 zmod_zmult_self1       -> mod_mult_self2_is_0
  2524 zmod_zmult_self2       -> mod_mult_self1_is_0
  2525 zmod_1                 -> mod_by_1
  2526 zdiv_1                 -> div_by_1
  2527 zdvd_abs1              -> abs_dvd_iff
  2528 zdvd_abs2              -> dvd_abs_iff
  2529 zdvd_refl              -> dvd_refl
  2530 zdvd_trans             -> dvd_trans
  2531 zdvd_zadd              -> dvd_add
  2532 zdvd_zdiff             -> dvd_diff
  2533 zdvd_zminus_iff        -> dvd_minus_iff
  2534 zdvd_zminus2_iff       -> minus_dvd_iff
  2535 zdvd_zmultD            -> dvd_mult_right
  2536 zdvd_zmultD2           -> dvd_mult_left
  2537 zdvd_zmult_mono        -> mult_dvd_mono
  2538 zdvd_0_right           -> dvd_0_right
  2539 zdvd_0_left            -> dvd_0_left_iff
  2540 zdvd_1_left            -> one_dvd
  2541 zminus_dvd_iff         -> minus_dvd_iff
  2542 
  2543 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  2544 
  2545 * The real numbers offer decimal input syntax: 12.34 is translated
  2546 into 1234/10^2. This translation is not reversed upon output.
  2547 
  2548 * Theory Library/Polynomial defines an abstract type 'a poly of
  2549 univariate polynomials with coefficients of type 'a.  In addition to
  2550 the standard ring operations, it also supports div and mod.  Code
  2551 generation is also supported, using list-style constructors.
  2552 
  2553 * Theory Library/Inner_Product defines a class of real_inner for real
  2554 inner product spaces, with an overloaded operation inner :: 'a => 'a
  2555 => real.  Class real_inner is a subclass of real_normed_vector from
  2556 theory RealVector.
  2557 
  2558 * Theory Library/Product_Vector provides instances for the product
  2559 type 'a * 'b of several classes from RealVector and Inner_Product.
  2560 Definitions of addition, subtraction, scalar multiplication, norms,
  2561 and inner products are included.
  2562 
  2563 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  2564 addition to the field operations, numerals and case syntax are also
  2565 supported.
  2566 
  2567 * Theory Library/Diagonalize provides constructive version of Cantor's
  2568 first diagonalization argument.
  2569 
  2570 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  2571 zlcm (for int); carried together from various gcd/lcm developements in
  2572 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  2573 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  2574 may recover tupled syntax as follows:
  2575 
  2576     hide (open) const gcd
  2577     abbreviation gcd where
  2578       "gcd == (%(a, b). GCD.gcd a b)"
  2579     notation (output)
  2580       GCD.gcd ("gcd '(_, _')")
  2581 
  2582 The same works for lcm, zgcd, zlcm.
  2583 
  2584 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  2585 instantiations for algebraic structures.  Removed some duplicate
  2586 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  2587 
  2588 * ML antiquotation @{code} takes a constant as argument and generates
  2589 corresponding code in background and inserts name of the corresponding
  2590 resulting ML value/function/datatype constructor binding in place.
  2591 All occurrences of @{code} with a single ML block are generated
  2592 simultaneously.  Provides a generic and safe interface for
  2593 instrumentalizing code generation.  See
  2594 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  2595 In future you ought to refrain from ad-hoc compiling generated SML
  2596 code on the ML toplevel.  Note that (for technical reasons) @{code}
  2597 cannot refer to constants for which user-defined serializations are
  2598 set.  Refer to the corresponding ML counterpart directly in that
  2599 cases.
  2600 
  2601 * Command 'rep_datatype': instead of theorem names the command now
  2602 takes a list of terms denoting the constructors of the type to be
  2603 represented as datatype.  The characteristic theorems have to be
  2604 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  2605 have disappeared in favour of existing ones:
  2606 
  2607     unit_induct                 ~> unit.induct
  2608     prod_induct                 ~> prod.induct
  2609     sum_induct                  ~> sum.induct
  2610     Suc_Suc_eq                  ~> nat.inject
  2611     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  2612 
  2613 
  2614 *** HOL-Algebra ***
  2615 
  2616 * New locales for orders and lattices where the equivalence relation
  2617 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  2618 locales use a record structure with field eq for the equivalence.
  2619 
  2620 * New theory of factorial domains.
  2621 
  2622 * Units_l_inv and Units_r_inv are now simp rules by default.
  2623 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  2624 and/or r_inv will now also require deletion of these lemmas.
  2625 
  2626 * Renamed the following theorems, INCOMPATIBILITY:
  2627 
  2628 UpperD ~> Upper_memD
  2629 LowerD ~> Lower_memD
  2630 least_carrier ~> least_closed
  2631 greatest_carrier ~> greatest_closed
  2632 greatest_Lower_above ~> greatest_Lower_below
  2633 one_zero ~> carrier_one_zero
  2634 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  2635 
  2636 
  2637 *** HOL-Nominal ***
  2638 
  2639 * Nominal datatypes can now contain type-variables.
  2640 
  2641 * Commands 'nominal_inductive' and 'equivariance' work with local
  2642 theory targets.
  2643 
  2644 * Nominal primrec can now works with local theory targets and its
  2645 specification syntax now conforms to the general format as seen in
  2646 'inductive' etc.
  2647 
  2648 * Method "perm_simp" honours the standard simplifier attributes
  2649 (no_asm), (no_asm_use) etc.
  2650 
  2651 * The new predicate #* is defined like freshness, except that on the
  2652 left hand side can be a set or list of atoms.
  2653 
  2654 * Experimental command 'nominal_inductive2' derives strong induction
  2655 principles for inductive definitions.  In contrast to
  2656 'nominal_inductive', which can only deal with a fixed number of
  2657 binders, it can deal with arbitrary expressions standing for sets of
  2658 atoms to be avoided.  The only inductive definition we have at the
  2659 moment that needs this generalisation is the typing rule for Lets in
  2660 the algorithm W:
  2661 
  2662  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  2663  -----------------------------------------------------------------
  2664          Gamma |- Let x be t1 in t2 : T2
  2665 
  2666 In this rule one wants to avoid all the binders that are introduced by
  2667 "close Gamma T1".  We are looking for other examples where this
  2668 feature might be useful.  Please let us know.
  2669 
  2670 
  2671 *** HOLCF ***
  2672 
  2673 * Reimplemented the simplification procedure for proving continuity
  2674 subgoals.  The new simproc is extensible; users can declare additional
  2675 continuity introduction rules with the attribute [cont2cont].
  2676 
  2677 * The continuity simproc now uses a different introduction rule for
  2678 solving continuity subgoals on terms with lambda abstractions.  In
  2679 some rare cases the new simproc may fail to solve subgoals that the
  2680 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  2681 Potential INCOMPATIBILITY.
  2682 
  2683 * Command 'fixrec': specification syntax now conforms to the general
  2684 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  2685 examples.  INCOMPATIBILITY.
  2686 
  2687 
  2688 *** ZF ***
  2689 
  2690 * Proof of Zorn's Lemma for partial orders.
  2691 
  2692 
  2693 *** ML ***
  2694 
  2695 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  2696 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  2697 depends on multithreading, so timouts will not work before Poly/ML
  2698 5.2.1!
  2699 
  2700 * High-level support for concurrent ML programming, see
  2701 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  2702 particularly convenient to organize independent functional
  2703 computations.  The concept of "synchronized variables" provides a
  2704 higher-order interface for components with shared state, avoiding the
  2705 delicate details of mutexes and condition variables.  (Requires
  2706 Poly/ML 5.2.1 or later.)
  2707 
  2708 * ML bindings produced via Isar commands are stored within the Isar
  2709 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2710 become thread-safe and work with undo as expected (concerning
  2711 top-level bindings, not side-effects on global references).
  2712 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2713 compiler at runtime; really global bindings need to be given outside a
  2714 theory.  (Requires Poly/ML 5.2 or later.)
  2715 
  2716 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2717 context.  Top-level ML bindings are stored within the proof context in
  2718 a purely sequential fashion, disregarding the nested proof structure.
  2719 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2720 proof.  (Requires Poly/ML 5.2 or later.)
  2721 
  2722 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2723 and Method.setup, as well as Isar commands 'attribute_setup' and
  2724 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2725 existing code accordingly, or use plain 'setup' together with old
  2726 Method.add_method.
  2727 
  2728 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2729 to 'a -> thm, while results are always tagged with an authentic oracle
  2730 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2731 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2732 accordingly.  Note that extra performance may be gained by producing
  2733 the cterm carefully, avoiding slow Thm.cterm_of.
  2734 
  2735 * Simplified interface for defining document antiquotations via
  2736 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2737 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2738 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2739 examples.
  2740 
  2741 * More systematic treatment of long names, abstract name bindings, and
  2742 name space operations.  Basic operations on qualified names have been
  2743 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2744 Long_Name.append.  Old type bstring has been mostly replaced by
  2745 abstract type binding (see structure Binding), which supports precise
  2746 qualification by packages and local theory targets, as well as proper
  2747 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2748 bstring values into Binding.name, or better pass through abstract
  2749 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2750 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2751 
  2752 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2753 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2754 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2755 
  2756 * Disposed old type and term read functions (Sign.read_def_typ,
  2757 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2758 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2759 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2760 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2761 resort for legacy applications.
  2762 
  2763 * Disposed old declarations, tactics, tactic combinators that refer to
  2764 the simpset or claset of an implicit theory (such as Addsimps,
  2765 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2766 embedded ML text, or local_simpset_of with a proper context passed as
  2767 explicit runtime argument.
  2768 
  2769 * Rules and tactics that read instantiations (read_instantiate,
  2770 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2771 context, which is required for parsing and type-checking.  Moreover,
  2772 the variables are specified as plain indexnames, not string encodings
  2773 thereof.  INCOMPATIBILITY.
  2774 
  2775 * Generic Toplevel.add_hook interface allows to analyze the result of
  2776 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2777 for theorem dependency output of transactions resulting in a new
  2778 theory state.
  2779 
  2780 * ML antiquotations: block-structured compilation context indicated by
  2781 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2782 
  2783   @{binding name}                         - basic name binding
  2784   @{let ?pat = term}                      - term abbreviation (HO matching)
  2785   @{note name = fact}                     - fact abbreviation
  2786   @{thm fact}                             - singleton fact (with attributes)
  2787   @{thms fact}                            - general fact (with attributes)
  2788   @{lemma prop by method}                 - singleton goal
  2789   @{lemma prop by meth1 meth2}            - singleton goal
  2790   @{lemma prop1 ... propN by method}      - general goal
  2791   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2792   @{lemma (open) ...}                     - open derivation
  2793 
  2794 
  2795 *** System ***
  2796 
  2797 * The Isabelle "emacs" tool provides a specific interface to invoke
  2798 Proof General / Emacs, with more explicit failure if that is not
  2799 installed (the old isabelle-interface script silently falls back on
  2800 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2801 installation location of the Proof General distribution.
  2802 
  2803 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2804 the Isabelle process into a JVM/Scala application.  See
  2805 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2806 process wrapper has been discontinued.)
  2807 
  2808 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2809 
  2810 * Various status messages (with exact source position information) are
  2811 emitted, if proper markup print mode is enabled.  This allows
  2812 user-interface components to provide detailed feedback on internal
  2813 prover operations.
  2814 
  2815 
  2816 
  2817 New in Isabelle2008 (June 2008)
  2818 -------------------------------
  2819 
  2820 *** General ***
  2821 
  2822 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2823 and updated, with formally checked references as hyperlinks.
  2824 
  2825 * Theory loader: use_thy (and similar operations) no longer set the
  2826 implicit ML context, which was occasionally hard to predict and in
  2827 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2828 provides a proper context already.
  2829 
  2830 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2831 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2832 'use' within a theory file will do the job.
  2833 
  2834 * Name space merge now observes canonical order, i.e. the second space
  2835 is inserted into the first one, while existing entries in the first
  2836 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2837 swap theory imports.
  2838 
  2839 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2840 INCOMPATIBILITY in identifier syntax etc.
  2841 
  2842 * Outer syntax: string tokens no longer admit escaped white space,
  2843 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2844 white space without escapes.
  2845 
  2846 * Outer syntax: string tokens may contain arbitrary character codes
  2847 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2848 "foo_bar".
  2849 
  2850 
  2851 *** Pure ***
  2852 
  2853 * Context-dependent token translations.  Default setup reverts locally
  2854 fixed variables, and adds hilite markup for undeclared frees.
  2855 
  2856 * Unused theorems can be found using the new command 'unused_thms'.
  2857 There are three ways of invoking it:
  2858 
  2859 (1) unused_thms
  2860      Only finds unused theorems in the current theory.
  2861 
  2862 (2) unused_thms thy_1 ... thy_n -
  2863      Finds unused theorems in the current theory and all of its ancestors,
  2864      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2865 
  2866 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2867      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2868      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2869      their ancestors.
  2870 
  2871 In order to increase the readability of the list produced by
  2872 unused_thms, theorems that have been created by a particular instance
  2873 of a theory command such as 'inductive' or 'function' are considered
  2874 to belong to the same "group", meaning that if at least one theorem in
  2875 this group is used, the other theorems in the same group are no longer
  2876 reported as unused.  Moreover, if all theorems in the group are
  2877 unused, only one theorem in the group is displayed.
  2878 
  2879 Note that proof objects have to be switched on in order for
  2880 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2881 usually the case when using Proof General with the default settings).
  2882 
  2883 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2884 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2885 duplicate fact bindings, or even accidental fact duplications.  Note
  2886 that tools may maintain dynamically scoped facts systematically, using
  2887 PureThy.add_thms_dynamic.
  2888 
  2889 * Command 'hide' now allows to hide from "fact" name space as well.
  2890 
  2891 * Eliminated destructive theorem database, simpset, claset, and
  2892 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2893 update of theories within ML code.
  2894 
  2895 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2896 INCOMPATIBILITY, object-logics depending on former Pure require
  2897 additional setup PureThy.old_appl_syntax_setup; object-logics
  2898 depending on former CPure need to refer to Pure.
  2899 
  2900 * Commands 'use' and 'ML' are now purely functional, operating on
  2901 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2902 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2903 INCOMPATIBILITY.
  2904 
  2905 * Command 'setup': discontinued implicit version with ML reference.
  2906 
  2907 * Instantiation target allows for simultaneous specification of class
  2908 instance operations together with an instantiation proof.
  2909 Type-checking phase allows to refer to class operations uniformly.
  2910 See src/HOL/Complex/Complex.thy for an Isar example and
  2911 src/HOL/Library/Eval.thy for an ML example.
  2912 
  2913 * Indexing of literal facts: be more serious about including only
  2914 facts from the visible specification/proof context, but not the
  2915 background context (locale etc.).  Affects `prop` notation and method
  2916 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2917 situations.
  2918 
  2919 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2920 "(open)" option, which used to expose internal bound variables to the
  2921 proof text.
  2922 
  2923 * Isar statements: removed obsolete case "rule_context".
  2924 INCOMPATIBILITY, better use explicit fixes/assumes.
  2925 
  2926 * Locale proofs: default proof step now includes 'unfold_locales';
  2927 hence 'proof' without argument may be used to unfold locale
  2928 predicates.
  2929 
  2930 
  2931 *** Document preparation ***
  2932 
  2933 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2934 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2935 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2936 spot); renamed link color from "darkblue" to "linkcolor" (default
  2937 value unchanged, can be redefined via \definecolor); no longer sets
  2938 "a4paper" option (unnecessary or even intrusive).
  2939 
  2940 * Antiquotation @{lemma A method} proves proposition A by the given
  2941 method (either a method name or a method name plus (optional) method
  2942 arguments in parentheses) and prints A just like @{prop A}.
  2943 
  2944 
  2945 *** HOL ***
  2946 
  2947 * New primrec package.  Specification syntax conforms in style to
  2948 definition/function/....  No separate induction rule is provided.  The
  2949 "primrec" command distinguishes old-style and new-style specifications
  2950 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2951 When adjusting theories, beware: constants stemming from new-style
  2952 primrec specifications have authentic syntax.
  2953 
  2954 * Metis prover is now an order of magnitude faster, and also works
  2955 with multithreading.
  2956 
  2957 * Metis: the maximum number of clauses that can be produced from a
  2958 theorem is now given by the attribute max_clauses.  Theorems that
  2959 exceed this number are ignored, with a warning printed.
  2960 
  2961 * Sledgehammer no longer produces structured proofs by default. To
  2962 enable, declare [[sledgehammer_full = true]].  Attributes
  2963 reconstruction_modulus, reconstruction_sorts renamed
  2964 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2965 
  2966 * Method "induct_scheme" derives user-specified induction rules
  2967 from well-founded induction and completeness of patterns. This factors
  2968 out some operations that are done internally by the function package
  2969 and makes them available separately.  See
  2970 src/HOL/ex/Induction_Scheme.thy for examples.
  2971 
  2972 * More flexible generation of measure functions for termination
  2973 proofs: Measure functions can be declared by proving a rule of the
  2974 form "is_measure f" and giving it the [measure_function] attribute.
  2975 The "is_measure" predicate is logically meaningless (always true), and
  2976 just guides the heuristic.  To find suitable measure functions, the
  2977 termination prover sets up the goal "is_measure ?f" of the appropriate
  2978 type and generates all solutions by prolog-style backwards proof using
  2979 the declared rules.
  2980 
  2981 This setup also deals with rules like 
  2982 
  2983   "is_measure f ==> is_measure (list_size f)"
  2984 
  2985 which accommodates nested datatypes that recurse through lists.
  2986 Similar rules are predeclared for products and option types.
  2987 
  2988 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  2989 
  2990   INCOMPATIBILITIES:
  2991 
  2992   - Definitions of overloaded constants on sets have to be replaced by
  2993     definitions on => and bool.
  2994 
  2995   - Some definitions of overloaded operators on sets can now be proved
  2996     using the definitions of the operators on => and bool.  Therefore,
  2997     the following theorems have been renamed:
  2998 
  2999       subset_def   -> subset_eq
  3000       psubset_def  -> psubset_eq
  3001       set_diff_def -> set_diff_eq
  3002       Compl_def    -> Compl_eq
  3003       Sup_set_def  -> Sup_set_eq
  3004       Inf_set_def  -> Inf_set_eq
  3005       sup_set_def  -> sup_set_eq
  3006       inf_set_def  -> inf_set_eq
  3007 
  3008   - Due to the incompleteness of the HO unification algorithm, some
  3009     rules such as subst may require manual instantiation, if some of
  3010     the unknowns in the rule is a set.
  3011 
  3012   - Higher order unification and forward proofs:
  3013     The proof pattern
  3014 
  3015       have "P (S::'a set)" <...>
  3016       then have "EX S. P S" ..
  3017 
  3018     no longer works (due to the incompleteness of the HO unification
  3019     algorithm) and must be replaced by the pattern
  3020 
  3021       have "EX S. P S"
  3022       proof
  3023         show "P S" <...>
  3024       qed
  3025 
  3026   - Calculational reasoning with subst (or similar rules):
  3027     The proof pattern
  3028 
  3029       have "P (S::'a set)" <...>
  3030       also have "S = T" <...>
  3031       finally have "P T" .
  3032 
  3033     no longer works (for similar reasons as the previous example) and
  3034     must be replaced by something like
  3035 
  3036       have "P (S::'a set)" <...>
  3037       moreover have "S = T" <...>
  3038       ultimately have "P T" by simp
  3039 
  3040   - Tactics or packages written in ML code:
  3041     Code performing pattern matching on types via
  3042 
  3043       Type ("set", [T]) => ...
  3044 
  3045     must be rewritten. Moreover, functions like strip_type or
  3046     binder_types no longer return the right value when applied to a
  3047     type of the form
  3048 
  3049       T1 => ... => Tn => U => bool
  3050 
  3051     rather than
  3052 
  3053       T1 => ... => Tn => U set
  3054 
  3055 * Merged theories Wellfounded_Recursion, Accessible_Part and
  3056 Wellfounded_Relations to theory Wellfounded.
  3057 
  3058 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  3059 
  3060 * Class finite no longer treats UNIV as class parameter.  Use class
  3061 enum from theory Library/Enum instead to achieve a similar effect.
  3062 INCOMPATIBILITY.
  3063 
  3064 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  3065 and "Cons".  INCOMPATIBILITY.
  3066 
  3067 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  3068 Potential INCOMPATIBILITY.
  3069 
  3070 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  3071 injective_fst_snd removed, use split_eta and prod_eqI instead.
  3072 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  3073 
  3074 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  3075 the same name in theory Orderings:
  3076 
  3077   less_trans
  3078   less_linear
  3079   le_imp_less_or_eq
  3080   le_less_trans
  3081   less_le_trans
  3082   less_not_sym
  3083   less_asym
  3084 
  3085 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  3086 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  3087 and different variable names.
  3088 
  3089 * Library/Option_ord.thy: Canonical order on option type.
  3090 
  3091 * Library/RBT.thy: Red-black trees, an efficient implementation of
  3092 finite maps.
  3093 
  3094 * Library/Countable.thy: Type class for countable types.
  3095 
  3096 * Theory Int: The representation of numerals has changed.  The infix
  3097 operator BIT and the bit datatype with constructors B0 and B1 have
  3098 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  3099 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  3100 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  3101 accordingly.
  3102 
  3103 * Theory Nat: definition of <= and < on natural numbers no longer
  3104 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  3105 le_def and less_def have disappeared.  Consider lemmas not_less
  3106 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  3107 
  3108 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  3109 (whose purpose mainly is for various fold_set functionals) have been
  3110 abandoned in favor of the existing algebraic classes
  3111 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  3112 lower_semilattice (resp. upper_semilattice) and linorder.
  3113 INCOMPATIBILITY.
  3114 
  3115 * Theory Transitive_Closure: induct and cases rules now declare proper
  3116 case_names ("base" and "step").  INCOMPATIBILITY.
  3117 
  3118 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  3119 lattices.  The form set-specific version is available as
  3120 Inductive.lfp_ordinal_induct_set.
  3121 
  3122 * Renamed theorems "power.simps" to "power_int.simps".
  3123 INCOMPATIBILITY.
  3124 
  3125 * Class semiring_div provides basic abstract properties of semirings
  3126 with division and modulo operations.  Subsumes former class dvd_mod.
  3127 
  3128 * Merged theories IntDef, Numeral and IntArith into unified theory
  3129 Int.  INCOMPATIBILITY.
  3130 
  3131 * Theory Library/Code_Index: type "index" now represents natural
  3132 numbers rather than integers.  INCOMPATIBILITY.
  3133 
  3134 * New class "uminus" with operation "uminus" (split of from class
  3135 "minus" which now only has operation "minus", binary).
  3136 INCOMPATIBILITY.
  3137 
  3138 * Constants "card", "internal_split", "option_map" now with authentic
  3139 syntax.  INCOMPATIBILITY.
  3140 
  3141 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  3142 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  3143 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  3144 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  3145 Sup_set_def, le_def, less_def, option_map_def now with object
  3146 equality.  INCOMPATIBILITY.
  3147 
  3148 * Records. Removed K_record, and replaced it by pure lambda term
  3149 %x. c. The simplifier setup is now more robust against eta expansion.
  3150 INCOMPATIBILITY: in cases explicitly referring to K_record.
  3151 
  3152 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  3153 
  3154 * Library/ListVector: new theory of arithmetic vector operations.
  3155 
  3156 * Library/Order_Relation: new theory of various orderings as sets of
  3157 pairs.  Defines preorders, partial orders, linear orders and
  3158 well-orders on sets and on types.
  3159 
  3160 
  3161 *** ZF ***
  3162 
  3163 * Renamed some theories to allow to loading both ZF and HOL in the
  3164 same session:
  3165 
  3166   Datatype  -> Datatype_ZF
  3167   Inductive -> Inductive_ZF
  3168   Int       -> Int_ZF
  3169   IntDiv    -> IntDiv_ZF
  3170   Nat       -> Nat_ZF
  3171   List      -> List_ZF
  3172   Main      -> Main_ZF
  3173 
  3174 INCOMPATIBILITY: ZF theories that import individual theories below
  3175 Main might need to be adapted.  Regular theory Main is still
  3176 available, as trivial extension of Main_ZF.
  3177 
  3178 
  3179 *** ML ***
  3180 
  3181 * ML within Isar: antiquotation @{const name} or @{const
  3182 name(typargs)} produces statically-checked Const term.
  3183 
  3184 * Functor NamedThmsFun: data is available to the user as dynamic fact
  3185 (of the same name).  Removed obsolete print command.
  3186 
  3187 * Removed obsolete "use_legacy_bindings" function.
  3188 
  3189 * The ``print mode'' is now a thread-local value derived from a global
  3190 template (the former print_mode reference), thus access becomes
  3191 non-critical.  The global print_mode reference is for session
  3192 management only; user-code should use print_mode_value,
  3193 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  3194 
  3195 * Functions system/system_out provide a robust way to invoke external
  3196 shell commands, with propagation of interrupts (requires Poly/ML
  3197 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  3198 
  3199 
  3200 *** System ***
  3201 
  3202 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  3203 in accordance with Proof General 3.7, which prefers GNU emacs.
  3204 
  3205 * isatool tty runs Isabelle process with plain tty interaction;
  3206 optional line editor may be specified via ISABELLE_LINE_EDITOR
  3207 setting, the default settings attempt to locate "ledit" and "rlwrap".
  3208 
  3209 * isatool browser now works with Cygwin as well, using general
  3210 "javapath" function defined in Isabelle process environment.
  3211 
  3212 * YXML notation provides a simple and efficient alternative to
  3213 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  3214 isatool yxml as described in the Isabelle system manual.
  3215 
  3216 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  3217 provides general wrapper for managing an Isabelle process in a robust
  3218 fashion, with ``cooked'' output from stdin/stderr.
  3219 
  3220 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  3221 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  3222 
  3223 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  3224 way of changing the user's settings is via
  3225 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  3226 script.
  3227 
  3228 * Multithreading.max_threads := 0 refers to the number of actual CPU
  3229 cores of the underlying machine, which is a good starting point for
  3230 optimal performance tuning.  The corresponding usedir option -M allows
  3231 "max" as an alias for "0".  WARNING: does not work on certain versions
  3232 of Mac OS (with Poly/ML 5.1).
  3233 
  3234 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  3235 adverse effect of Isabelle flooding interactive front-ends (notably
  3236 ProofGeneral / XEmacs).
  3237 
  3238 
  3239 
  3240 New in Isabelle2007 (November 2007)
  3241 -----------------------------------
  3242 
  3243 *** General ***
  3244 
  3245 * More uniform information about legacy features, notably a
  3246 warning/error of "Legacy feature: ...", depending on the state of the
  3247 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  3248 legacy features will disappear eventually.
  3249 
  3250 * Theory syntax: the header format ``theory A = B + C:'' has been
  3251 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  3252 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  3253 
  3254 * Theory syntax: the old non-Isar theory file format has been
  3255 discontinued altogether.  Note that ML proof scripts may still be used
  3256 with Isar theories; migration is usually quite simple with the ML
  3257 function use_legacy_bindings.  INCOMPATIBILITY.
  3258 
  3259 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  3260 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  3261 quotes.
  3262 
  3263 * Theory loader: be more serious about observing the static theory
  3264 header specifications (including optional directories), but not the
  3265 accidental file locations of previously successful loads.  The strict
  3266 update policy of former update_thy is now already performed by
  3267 use_thy, so the former has been removed; use_thys updates several
  3268 theories simultaneously, just as 'imports' within a theory header
  3269 specification, but without merging the results.  Potential
  3270 INCOMPATIBILITY: may need to refine theory headers and commands
  3271 ROOT.ML which depend on load order.
  3272 
  3273 * Theory loader: optional support for content-based file
  3274 identification, instead of the traditional scheme of full physical
  3275 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  3276 (cf. the system manual).  The new scheme allows to work with
  3277 non-finished theories in persistent session images, such that source
  3278 files may be moved later on without requiring reloads.
  3279 
  3280 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3281 file (with the same base name as the theory) are considered a legacy
  3282 feature, which will disappear eventually. Even now, the theory loader
  3283 no longer maintains dependencies on such files.
  3284 
  3285 * Syntax: the scope for resolving ambiguities via type-inference is
  3286 now limited to individual terms, instead of whole simultaneous
  3287 specifications as before. This greatly reduces the complexity of the
  3288 syntax module and improves flexibility by separating parsing and
  3289 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  3290 'fixes' etc.) are required in rare situations.
  3291 
  3292 * Syntax: constants introduced by new-style packages ('definition',
  3293 'abbreviation' etc.) are passed through the syntax module in
  3294 ``authentic mode''. This means that associated mixfix annotations
  3295 really stick to such constants, independently of potential name space
  3296 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  3297 trees are represented slightly differently, may need to adapt syntax
  3298 translations accordingly. Use CONST marker in 'translations' and
  3299 @{const_syntax} antiquotation in 'parse_translation' etc.
  3300 
  3301 * Legacy goal package: reduced interface to the bare minimum required
  3302 to keep existing proof scripts running.  Most other user-level
  3303 functions are now part of the OldGoals structure, which is *not* open
  3304 by default (consider isatool expandshort before open OldGoals).
  3305 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  3306 these tend to cause confusion about the actual goal (!) context being
  3307 used here, which is not necessarily the same as the_context().
  3308 
  3309 * Command 'find_theorems': supports "*" wild-card in "name:"
  3310 criterion; "with_dups" option.  Certain ProofGeneral versions might
  3311 support a specific search form (see ProofGeneral/CHANGES).
  3312 
  3313 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  3314 by default, which means that "prems" (and also "fixed variables") are
  3315 suppressed from proof state output.  Note that the ProofGeneral
  3316 settings mechanism allows to change and save options persistently, but
  3317 older versions of Isabelle will fail to start up if a negative prems
  3318 limit is imposed.
  3319 
  3320 * Local theory targets may be specified by non-nested blocks of
  3321 ``context/locale/class ... begin'' followed by ``end''.  The body may
  3322 contain definitions, theorems etc., including any derived mechanism
  3323 that has been implemented on top of these primitives.  This concept
  3324 generalizes the existing ``theorem (in ...)'' towards more versatility
  3325 and scalability.
  3326 
  3327 * Proof General interface: proper undo of final 'end' command;
  3328 discontinued Isabelle/classic mode (ML proof scripts).
  3329 
  3330 
  3331 *** Document preparation ***
  3332 
  3333 * Added antiquotation @{theory name} which prints the given name,
  3334 after checking that it refers to a valid ancestor theory in the
  3335 current context.
  3336 
  3337 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  3338 check the given source text as ML type/structure, printing verbatim.
  3339 
  3340 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  3341 "c args == rhs" given in the current context.  (Any number of
  3342 arguments may be given on the LHS.)
  3343 
  3344 
  3345 *** Pure ***
  3346 
  3347 * The 'class' package offers a combination of axclass and locale to
  3348 achieve Haskell-like type classes in Isabelle.  Definitions and
  3349 theorems within a class context produce both relative results (with
  3350 implicit parameters according to the locale context), and polymorphic
  3351 constants with qualified polymorphism (according to the class
  3352 context).  Within the body context of a 'class' target, a separate
  3353 syntax layer ("user space type system") takes care of converting
  3354 between global polymorphic consts and internal locale representation.
  3355 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  3356 "isatool doc classes" provides a tutorial.
  3357 
  3358 * Generic code generator framework allows to generate executable
  3359 code for ML and Haskell (including Isabelle classes).  A short usage
  3360 sketch:
  3361 
  3362     internal compilation:
  3363         export_code <list of constants (term syntax)> in SML
  3364     writing SML code to a file:
  3365         export_code <list of constants (term syntax)> in SML <filename>
  3366     writing OCaml code to a file:
  3367         export_code <list of constants (term syntax)> in OCaml <filename>
  3368     writing Haskell code to a bunch of files:
  3369         export_code <list of constants (term syntax)> in Haskell <filename>
  3370 
  3371     evaluating closed propositions to True/False using code generation:
  3372         method ``eval''
  3373 
  3374 Reasonable default setup of framework in HOL.
  3375 
  3376 Theorem attributs for selecting and transforming function equations theorems:
  3377 
  3378     [code fun]:        select a theorem as function equation for a specific constant
  3379     [code fun del]:    deselect a theorem as function equation for a specific constant
  3380     [code inline]:     select an equation theorem for unfolding (inlining) in place
  3381     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  3382 
  3383 User-defined serializations (target in {SML, OCaml, Haskell}):
  3384 
  3385     code_const <and-list of constants (term syntax)>
  3386       {(target) <and-list of const target syntax>}+
  3387 
  3388     code_type <and-list of type constructors>
  3389       {(target) <and-list of type target syntax>}+
  3390 
  3391     code_instance <and-list of instances>
  3392       {(target)}+
  3393         where instance ::= <type constructor> :: <class>
  3394 
  3395     code_class <and_list of classes>
  3396       {(target) <and-list of class target syntax>}+
  3397         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  3398 
  3399 code_instance and code_class only are effective to target Haskell.
  3400 
  3401 For example usage see src/HOL/ex/Codegenerator.thy and
  3402 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  3403 generation from Isabelle/HOL theories is available via "isatool doc
  3404 codegen".
  3405 
  3406 * Code generator: consts in 'consts_code' Isar commands are now
  3407 referred to by usual term syntax (including optional type
  3408 annotations).
  3409 
  3410 * Command 'no_translations' removes translation rules from theory
  3411 syntax.
  3412 
  3413 * Overloaded definitions are now actually checked for acyclic
  3414 dependencies.  The overloading scheme is slightly more general than
  3415 that of Haskell98, although Isabelle does not demand an exact
  3416 correspondence to type class and instance declarations.
  3417 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  3418 exotic versions of overloading -- at the discretion of the user!
  3419 
  3420 Polymorphic constants are represented via type arguments, i.e. the
  3421 instantiation that matches an instance against the most general
  3422 declaration given in the signature.  For example, with the declaration
  3423 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  3424 as c(nat).  Overloading is essentially simultaneous structural
  3425 recursion over such type arguments.  Incomplete specification patterns
  3426 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  3427 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  3428 Command 'print_theory' outputs the normalized system of recursive
  3429 equations, see section "definitions".
  3430 
  3431 * Configuration options are maintained within the theory or proof
  3432 context (with name and type bool/int/string), providing a very simple
  3433 interface to a poor-man's version of general context data.  Tools may
  3434 declare options in ML (e.g. using Attrib.config_int) and then refer to
  3435 these values using Config.get etc.  Users may change options via an
  3436 associated attribute of the same name.  This form of context
  3437 declaration works particularly well with commands 'declare' or
  3438 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  3439 very easy to avoid global references, which would not observe Isar
  3440 toplevel undo/redo and fail to work with multithreading.
  3441 
  3442 Various global ML references of Pure and HOL have been turned into
  3443 configuration options:
  3444 
  3445   Unify.search_bound		unify_search_bound
  3446   Unify.trace_bound		unify_trace_bound
  3447   Unify.trace_simp		unify_trace_simp
  3448   Unify.trace_types		unify_trace_types
  3449   Simplifier.simp_depth_limit	simp_depth_limit
  3450   Blast.depth_limit		blast_depth_limit
  3451   DatatypeProp.dtK		datatype_distinctness_limit
  3452   fast_arith_neq_limit  	fast_arith_neq_limit
  3453   fast_arith_split_limit	fast_arith_split_limit
  3454 
  3455 * Named collections of theorems may be easily installed as context
  3456 data using the functor NamedThmsFun (see also
  3457 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  3458 attributes; there is also a toplevel print command.  This facility is
  3459 just a common case of general context data, which is the preferred way
  3460 for anything more complex than just a list of facts in canonical
  3461 order.
  3462 
  3463 * Isar: command 'declaration' augments a local theory by generic
  3464 declaration functions written in ML.  This enables arbitrary content
  3465 being added to the context, depending on a morphism that tells the
  3466 difference of the original declaration context wrt. the application
  3467 context encountered later on.
  3468 
  3469 * Isar: proper interfaces for simplification procedures.  Command
  3470 'simproc_setup' declares named simprocs (with match patterns, and body
  3471 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  3472 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  3473 
  3474 * Isar: an extra pair of brackets around attribute declarations
  3475 abbreviates a theorem reference involving an internal dummy fact,
  3476 which will be ignored later --- only the effect of the attribute on
  3477 the background context will persist.  This form of in-place
  3478 declarations is particularly useful with commands like 'declare' and
  3479 'using', for example ``have A using [[simproc a]] by simp''.
  3480 
  3481 * Isar: method "assumption" (and implicit closing of subproofs) now
  3482 takes simple non-atomic goal assumptions into account: after applying
  3483 an assumption as a rule the resulting subgoals are solved by atomic
  3484 assumption steps.  This is particularly useful to finish 'obtain'
  3485 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  3486 without referring to the original premise "!!x. P x ==> thesis" in the
  3487 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  3488 more permissive.
  3489 
  3490 * Isar: implicit use of prems from the Isar proof context is
  3491 considered a legacy feature.  Common applications like ``have A .''
  3492 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  3493 referencing facts explicitly here improves readability and
  3494 maintainability of proof texts.
  3495 
  3496 * Isar: improper proof element 'guess' is like 'obtain', but derives
  3497 the obtained context from the course of reasoning!  For example:
  3498 
  3499   assume "EX x y. A x & B y"   -- "any previous fact"
  3500   then guess x and y by clarify
  3501 
  3502 This technique is potentially adventurous, depending on the facts and
  3503 proof tools being involved here.
  3504 
  3505 * Isar: known facts from the proof context may be specified as literal
  3506 propositions, using ASCII back-quote syntax.  This works wherever
  3507 named facts used to be allowed so far, in proof commands, proof
  3508 methods, attributes etc.  Literal facts are retrieved from the context
  3509 according to unification of type and term parameters.  For example,
  3510 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  3511 theorems in the current context, then these are valid literal facts:
  3512 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  3513 
  3514 There is also a proof method "fact" which does the same composition
  3515 for explicit goal states, e.g. the following proof texts coincide with
  3516 certain special cases of literal facts:
  3517 
  3518   have "A" by fact                 ==  note `A`
  3519   have "A ==> B" by fact           ==  note `A ==> B`
  3520   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  3521   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  3522 
  3523 * Isar: ":" (colon) is no longer a symbolic identifier character in
  3524 outer syntax.  Thus symbolic identifiers may be used without
  3525 additional white space in declarations like this: ``assume *: A''.
  3526 
  3527 * Isar: 'print_facts' prints all local facts of the current context,
  3528 both named and unnamed ones.
  3529 
  3530 * Isar: 'def' now admits simultaneous definitions, e.g.:
  3531 
  3532   def x == "t" and y == "u"
  3533 
  3534 * Isar: added command 'unfolding', which is structurally similar to
  3535 'using', but affects both the goal state and facts by unfolding given
  3536 rewrite rules.  Thus many occurrences of the 'unfold' method or
  3537 'unfolded' attribute may be replaced by first-class proof text.
  3538 
  3539 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  3540 and command 'unfolding' now all support object-level equalities
  3541 (potentially conditional).  The underlying notion of rewrite rule is
  3542 analogous to the 'rule_format' attribute, but *not* that of the
  3543 Simplifier (which is usually more generous).
  3544 
  3545 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  3546 premises of a theorem by n. Useful in conjunction with drule.
  3547 
  3548 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  3549 method expression within a sandbox consisting of the first N
  3550 sub-goals, which need to exist.  For example, ``simp_all [3]''
  3551 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  3552 simplifies all new goals that emerge from applying rule foo to the
  3553 originally first one.
  3554 
  3555 * Isar: schematic goals are no longer restricted to higher-order
  3556 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  3557 expected.
  3558 
  3559 * Isar: the conclusion of a long theorem statement is now either
  3560 'shows' (a simultaneous conjunction, as before), or 'obtains'
  3561 (essentially a disjunction of cases with local parameters and
  3562 assumptions).  The latter allows to express general elimination rules
  3563 adequately; in this notation common elimination rules look like this:
  3564 
  3565   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  3566     assumes "EX x. P x"
  3567     obtains x where "P x"
  3568 
  3569   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  3570     assumes "A & B"
  3571     obtains A and B
  3572 
  3573   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  3574     assumes "A | B"
  3575     obtains
  3576       A
  3577     | B
  3578 
  3579 The subsequent classical rules even refer to the formal "thesis"
  3580 explicitly:
  3581 
  3582   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  3583     obtains "~ thesis"
  3584 
  3585   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  3586     obtains "thesis ==> something"
  3587 
  3588 The actual proof of an 'obtains' statement is analogous to that of the
  3589 Isar proof element 'obtain', only that there may be several cases.
  3590 Optional case names may be specified in parentheses; these will be
  3591 available both in the present proof and as annotations in the
  3592 resulting rule, for later use with the 'cases' method (cf. attribute
  3593 case_names).
  3594 
  3595 * Isar: the assumptions of a long theorem statement are available as
  3596 "assms" fact in the proof context.  This is more appropriate than the
  3597 (historical) "prems", which refers to all assumptions of the current
  3598 context, including those from the target locale, proof body etc.
  3599 
  3600 * Isar: 'print_statement' prints theorems from the current theory or
  3601 proof context in long statement form, according to the syntax of a
  3602 top-level lemma.
  3603 
  3604 * Isar: 'obtain' takes an optional case name for the local context
  3605 introduction rule (default "that").
  3606 
  3607 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  3608 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  3609 to occur.
  3610 
  3611 * Pure: syntax "CONST name" produces a fully internalized constant
  3612 according to the current context.  This is particularly useful for
  3613 syntax translations that should refer to internal constant
  3614 representations independently of name spaces.
  3615 
  3616 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  3617 instead of "FOO ". This allows multiple binder declarations to coexist
  3618 in the same context.  INCOMPATIBILITY.
  3619 
  3620 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  3621 primitive that also works in a locale context (both for constants and
  3622 fixed variables). Type declaration and internal syntactic representation
  3623 of given constants retrieved from the context. Likewise, the
  3624 'no_notation' command allows to remove given syntax annotations from the
  3625 current context.
  3626 
  3627 * Isar/locales: new derived specification elements 'axiomatization',
  3628 'definition', 'abbreviation', which support type-inference, admit
  3629 object-level specifications (equality, equivalence).  See also the
  3630 isar-ref manual.  Examples:
  3631 
  3632   axiomatization
  3633     eq  (infix "===" 50) where
  3634     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  3635 
  3636   definition "f x y = x + y + 1"
  3637   definition g where "g x = f x x"
  3638 
  3639   abbreviation
  3640     neq  (infix "=!=" 50) where
  3641     "x =!= y == ~ (x === y)"
  3642 
  3643 These specifications may be also used in a locale context.  Then the
  3644 constants being introduced depend on certain fixed parameters, and the
  3645 constant name is qualified by the locale base name.  An internal
  3646 abbreviation takes care for convenient input and output, making the
  3647 parameters implicit and using the original short name.  See also
  3648 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  3649 entities from a monomorphic theory.
  3650 
  3651 Presently, abbreviations are only available 'in' a target locale, but
  3652 not inherited by general import expressions.  Also note that
  3653 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  3654 'translations' in common applications.  The "no_abbrevs" print mode
  3655 prevents folding of abbreviations in term output.
  3656 
  3657 Concrete syntax is attached to specified constants in internal form,
  3658 independently of name spaces.  The parse tree representation is
  3659 slightly different -- use 'notation' instead of raw 'syntax', and
  3660 'translations' with explicit "CONST" markup to accommodate this.
  3661 
  3662 * Pure/Isar: unified syntax for new-style specification mechanisms
  3663 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  3664 full type inference and dummy patterns ("_").  For example:
  3665 
  3666   definition "K x _ = x"
  3667 
  3668   inductive conj for A B
  3669   where "A ==> B ==> conj A B"
  3670 
  3671 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  3672 the current context.  Print mode "no_abbrevs" prevents inversion of
  3673 abbreviations on output.
  3674 
  3675 * Isar/locales: improved parameter handling: use of locales "var" and
  3676 "struct" no longer necessary; - parameter renamings are no longer
  3677 required to be injective.  For example, this allows to define
  3678 endomorphisms as locale endom = homom mult mult h.
  3679 
  3680 * Isar/locales: changed the way locales with predicates are defined.
  3681 Instead of accumulating the specification, the imported expression is
  3682 now an interpretation.  INCOMPATIBILITY: different normal form of
  3683 locale expressions.  In particular, in interpretations of locales with
  3684 predicates, goals repesenting already interpreted fragments are not
  3685 removed automatically.  Use methods `intro_locales' and
  3686 `unfold_locales'; see below.
  3687 
  3688 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  3689 provide backward reasoning on locales predicates.  The methods are
  3690 aware of interpretations and discharge corresponding goals.
  3691 `intro_locales' is less aggressive then `unfold_locales' and does not
  3692 unfold predicates to assumptions.
  3693 
  3694 * Isar/locales: the order in which locale fragments are accumulated
  3695 has changed.  This enables to override declarations from fragments due
  3696 to interpretations -- for example, unwanted simp rules.
  3697 
  3698 * Isar/locales: interpretation in theories and proof contexts has been
  3699 extended.  One may now specify (and prove) equations, which are
  3700 unfolded in interpreted theorems.  This is useful for replacing
  3701 defined concepts (constants depending on locale parameters) by
  3702 concepts already existing in the target context.  Example:
  3703 
  3704   interpretation partial_order ["op <= :: [int, int] => bool"]
  3705     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3706 
  3707 Typically, the constant `partial_order.less' is created by a
  3708 definition specification element in the context of locale
  3709 partial_order.
  3710 
  3711 * Method "induct": improved internal context management to support
  3712 local fixes and defines on-the-fly. Thus explicit meta-level
  3713 connectives !!  and ==> are rarely required anymore in inductive goals
  3714 (using object-logic connectives for this purpose has been long
  3715 obsolete anyway). Common proof patterns are explained in
  3716 src/HOL/Induct/Common_Patterns.thy, see also
  3717 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3718 examples.
  3719 
  3720 * Method "induct": improved handling of simultaneous goals. Instead of
  3721 introducing object-level conjunction, the statement is now split into
  3722 several conclusions, while the corresponding symbolic cases are nested
  3723 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3724 see src/HOL/Induct/Common_Patterns.thy, for example.
  3725 
  3726 * Method "induct": mutual induction rules are now specified as a list
  3727 of rule sharing the same induction cases. HOL packages usually provide
  3728 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3729 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3730 mutual induction rules differently, i.e. like this:
  3731 
  3732   (induct rule: foo_bar.inducts)
  3733   (induct set: foo bar)
  3734   (induct pred: foo bar)
  3735   (induct type: foo bar)
  3736 
  3737 The ML function ProjectRule.projections turns old-style rules into the
  3738 new format.
  3739 
  3740 * Method "coinduct": dual of induction, see
  3741 src/HOL/Library/Coinductive_List.thy for various examples.
  3742 
  3743 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3744 considered a legacy feature.
  3745 
  3746 * Attribute "symmetric" produces result with standardized schematic
  3747 variables (index 0).  Potential INCOMPATIBILITY.
  3748 
  3749 * Simplifier: by default the simplifier trace only shows top level
  3750 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3751 default. Thus there is less danger of being flooded by the trace. The
  3752 trace indicates where parts have been suppressed.
  3753   
  3754 * Provers/classical: removed obsolete classical version of elim_format
  3755 attribute; classical elim/dest rules are now treated uniformly when
  3756 manipulating the claset.
  3757 
  3758 * Provers/classical: stricter checks to ensure that supplied intro,
  3759 dest and elim rules are well-formed; dest and elim rules must have at
  3760 least one premise.
  3761 
  3762 * Provers/classical: attributes dest/elim/intro take an optional
  3763 weight argument for the rule (just as the Pure versions).  Weights are
  3764 ignored by automated tools, but determine the search order of single
  3765 rule steps.
  3766 
  3767 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3768 where the body does not mention the bound variable.  Note that dummy
  3769 patterns implicitly depend on their context of bounds, which makes
  3770 "{_. _}" match any set comprehension as expected.  Potential
  3771 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3772 constant "_idtdummy" in the binding position.
  3773 
  3774 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3775 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3776 for example "A -> B" => "Pi A (%_. B)".
  3777 
  3778 * Pure: 'class_deps' command visualizes the subclass relation, using
  3779 the graph browser tool.
  3780 
  3781 * Pure: 'print_theory' now suppresses certain internal declarations by
  3782 default; use '!' option for full details.
  3783 
  3784 
  3785 *** HOL ***
  3786 
  3787 * Method "metis" proves goals by applying the Metis general-purpose
  3788 resolution prover (see also http://gilith.com/software/metis/).
  3789 Examples are in the directory MetisExamples.  WARNING: the
  3790 Isabelle/HOL-Metis integration does not yet work properly with
  3791 multi-threading.
  3792   
  3793 * Command 'sledgehammer' invokes external automatic theorem provers as
  3794 background processes.  It generates calls to the "metis" method if
  3795 successful. These can be pasted into the proof.  Users do not have to
  3796 wait for the automatic provers to return.  WARNING: does not really
  3797 work with multi-threading.
  3798 
  3799 * New "auto_quickcheck" feature tests outermost goal statements for
  3800 potential counter-examples.  Controlled by ML references
  3801 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3802 5000 milliseconds).  Fails silently if statements is outside of
  3803 executable fragment, or any other codgenerator problem occurs.
  3804 
  3805 * New constant "undefined" with axiom "undefined x = undefined".
  3806 
  3807 * Added class "HOL.eq", allowing for code generation with polymorphic
  3808 equality.
  3809 
  3810 * Some renaming of class constants due to canonical name prefixing in
  3811 the new 'class' package:
  3812 
  3813     HOL.abs ~> HOL.abs_class.abs
  3814     HOL.divide ~> HOL.divide_class.divide
  3815     0 ~> HOL.zero_class.zero
  3816     1 ~> HOL.one_class.one
  3817     op + ~> HOL.plus_class.plus
  3818     op - ~> HOL.minus_class.minus
  3819     uminus ~> HOL.minus_class.uminus
  3820     op * ~> HOL.times_class.times
  3821     op < ~> HOL.ord_class.less
  3822     op <= > HOL.ord_class.less_eq
  3823     Nat.power ~> Power.power_class.power
  3824     Nat.size ~> Nat.size_class.size
  3825     Numeral.number_of ~> Numeral.number_class.number_of
  3826     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3827     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3828     Orderings.min ~> Orderings.ord_class.min
  3829     Orderings.max ~> Orderings.ord_class.max
  3830     Divides.op div ~> Divides.div_class.div
  3831     Divides.op mod ~> Divides.div_class.mod
  3832     Divides.op dvd ~> Divides.div_class.dvd
  3833 
  3834 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3835 
  3836 a) User-defined constants using any of the names "plus", "minus",
  3837 "times", "less" or "less_eq". The standard syntax translations for
  3838 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3839 names.
  3840 
  3841 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3842 INCOMPATIBILITY: use more specific names.
  3843 
  3844 c) Permutative equations (e.g. "a + b = b + a")
  3845 Since the change of names also changes the order of terms, permutative
  3846 rewrite rules may get applied in a different order. Experience shows
  3847 that this is rarely the case (only two adaptions in the whole Isabelle
  3848 distribution).  INCOMPATIBILITY: rewrite proofs
  3849 
  3850 d) ML code directly refering to constant names
  3851 This in general only affects hand-written proof tactics, simprocs and
  3852 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3853 Consider using @{const_name} antiquotation.
  3854 
  3855 * New class "default" with associated constant "default".
  3856 
  3857 * Function "sgn" is now overloaded and available on int, real, complex
  3858 (and other numeric types), using class "sgn".  Two possible defs of
  3859 sgn are given as equational assumptions in the classes sgn_if and
  3860 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3861 INCOMPATIBILITY.
  3862 
  3863 * Locale "partial_order" now unified with class "order" (cf. theory
  3864 Orderings), added parameter "less".  INCOMPATIBILITY.
  3865 
  3866 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3867 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3868 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3869 
  3870 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3871 changed order of proof goals in instance proofs.
  3872 
  3873 * The transitivity reasoner for partial and linear orders is set up
  3874 for classes "order" and "linorder".  Instances of the reasoner are available
  3875 in all contexts importing or interpreting the corresponding locales.
  3876 Method "order" invokes the reasoner separately; the reasoner
  3877 is also integrated with the Simplifier as a solver.  Diagnostic
  3878 command 'print_orders' shows the available instances of the reasoner
  3879 in the current context.
  3880 
  3881 * Localized monotonicity predicate in theory "Orderings"; integrated
  3882 lemmas max_of_mono and min_of_mono with this predicate.
  3883 INCOMPATIBILITY.
  3884 
  3885 * Formulation of theorem "dense" changed slightly due to integration
  3886 with new class dense_linear_order.
  3887 
  3888 * Uniform lattice theory development in HOL.
  3889 
  3890     constants "meet" and "join" now named "inf" and "sup"
  3891     constant "Meet" now named "Inf"
  3892 
  3893     classes "meet_semilorder" and "join_semilorder" now named
  3894       "lower_semilattice" and "upper_semilattice"
  3895     class "lorder" now named "lattice"
  3896     class "comp_lat" now named "complete_lattice"
  3897 
  3898     Instantiation of lattice classes allows explicit definitions
  3899     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3900 
  3901   INCOMPATIBILITY.  Theorem renames:
  3902 
  3903     meet_left_le            ~> inf_le1
  3904     meet_right_le           ~> inf_le2
  3905     join_left_le            ~> sup_ge1
  3906     join_right_le           ~> sup_ge2
  3907     meet_join_le            ~> inf_sup_ord
  3908     le_meetI                ~> le_infI
  3909     join_leI                ~> le_supI
  3910     le_meet                 ~> le_inf_iff
  3911     le_join                 ~> ge_sup_conv
  3912     meet_idempotent         ~> inf_idem
  3913     join_idempotent         ~> sup_idem
  3914     meet_comm               ~> inf_commute
  3915     join_comm               ~> sup_commute
  3916     meet_leI1               ~> le_infI1
  3917     meet_leI2               ~> le_infI2
  3918     le_joinI1               ~> le_supI1
  3919     le_joinI2               ~> le_supI2
  3920     meet_assoc              ~> inf_assoc
  3921     join_assoc              ~> sup_assoc
  3922     meet_left_comm          ~> inf_left_commute
  3923     meet_left_idempotent    ~> inf_left_idem
  3924     join_left_comm          ~> sup_left_commute
  3925     join_left_idempotent    ~> sup_left_idem
  3926     meet_aci                ~> inf_aci
  3927     join_aci                ~> sup_aci
  3928     le_def_meet             ~> le_iff_inf
  3929     le_def_join             ~> le_iff_sup
  3930     join_absorp2            ~> sup_absorb2
  3931     join_absorp1            ~> sup_absorb1
  3932     meet_absorp1            ~> inf_absorb1
  3933     meet_absorp2            ~> inf_absorb2
  3934     meet_join_absorp        ~> inf_sup_absorb
  3935     join_meet_absorp        ~> sup_inf_absorb
  3936     distrib_join_le         ~> distrib_sup_le
  3937     distrib_meet_le         ~> distrib_inf_le
  3938 
  3939     add_meet_distrib_left   ~> add_inf_distrib_left
  3940     add_join_distrib_left   ~> add_sup_distrib_left
  3941     is_join_neg_meet        ~> is_join_neg_inf
  3942     is_meet_neg_join        ~> is_meet_neg_sup
  3943     add_meet_distrib_right  ~> add_inf_distrib_right
  3944     add_join_distrib_right  ~> add_sup_distrib_right
  3945     add_meet_join_distribs  ~> add_sup_inf_distribs
  3946     join_eq_neg_meet        ~> sup_eq_neg_inf
  3947     meet_eq_neg_join        ~> inf_eq_neg_sup
  3948     add_eq_meet_join        ~> add_eq_inf_sup
  3949     meet_0_imp_0            ~> inf_0_imp_0
  3950     join_0_imp_0            ~> sup_0_imp_0
  3951     meet_0_eq_0             ~> inf_0_eq_0
  3952     join_0_eq_0             ~> sup_0_eq_0
  3953     neg_meet_eq_join        ~> neg_inf_eq_sup
  3954     neg_join_eq_meet        ~> neg_sup_eq_inf
  3955     join_eq_if              ~> sup_eq_if
  3956 
  3957     mono_meet               ~> mono_inf
  3958     mono_join               ~> mono_sup
  3959     meet_bool_eq            ~> inf_bool_eq
  3960     join_bool_eq            ~> sup_bool_eq
  3961     meet_fun_eq             ~> inf_fun_eq
  3962     join_fun_eq             ~> sup_fun_eq
  3963     meet_set_eq             ~> inf_set_eq
  3964     join_set_eq             ~> sup_set_eq
  3965     meet1_iff               ~> inf1_iff
  3966     meet2_iff               ~> inf2_iff
  3967     meet1I                  ~> inf1I
  3968     meet2I                  ~> inf2I
  3969     meet1D1                 ~> inf1D1
  3970     meet2D1                 ~> inf2D1
  3971     meet1D2                 ~> inf1D2
  3972     meet2D2                 ~> inf2D2
  3973     meet1E                  ~> inf1E
  3974     meet2E                  ~> inf2E
  3975     join1_iff               ~> sup1_iff
  3976     join2_iff               ~> sup2_iff
  3977     join1I1                 ~> sup1I1
  3978     join2I1                 ~> sup2I1
  3979     join1I1                 ~> sup1I1
  3980     join2I2                 ~> sup1I2
  3981     join1CI                 ~> sup1CI
  3982     join2CI                 ~> sup2CI
  3983     join1E                  ~> sup1E
  3984     join2E                  ~> sup2E
  3985 
  3986     is_meet_Meet            ~> is_meet_Inf
  3987     Meet_bool_def           ~> Inf_bool_def
  3988     Meet_fun_def            ~> Inf_fun_def
  3989     Meet_greatest           ~> Inf_greatest
  3990     Meet_lower              ~> Inf_lower
  3991     Meet_set_def            ~> Inf_set_def
  3992 
  3993     Sup_def                 ~> Sup_Inf
  3994     Sup_bool_eq             ~> Sup_bool_def
  3995     Sup_fun_eq              ~> Sup_fun_def
  3996     Sup_set_eq              ~> Sup_set_def
  3997 
  3998     listsp_meetI            ~> listsp_infI
  3999     listsp_meet_eq          ~> listsp_inf_eq
  4000 
  4001     meet_min                ~> inf_min
  4002     join_max                ~> sup_max
  4003 
  4004 * Added syntactic class "size"; overloaded constant "size" now has
  4005 type "'a::size ==> bool"
  4006 
  4007 * Internal reorganisation of `size' of datatypes: size theorems
  4008 "foo.size" are no longer subsumed by "foo.simps" (but are still
  4009 simplification rules by default!); theorems "prod.size" now named
  4010 "*.size".
  4011 
  4012 * Class "div" now inherits from class "times" rather than "type".
  4013 INCOMPATIBILITY.
  4014 
  4015 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  4016 Linorder etc.  have disappeared; operations defined in terms of
  4017 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  4018 
  4019 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  4020 
  4021 * HOL-Word: New extensive library and type for generic, fixed size
  4022 machine words, with arithemtic, bit-wise, shifting and rotating
  4023 operations, reflection into int, nat, and bool lists, automation for
  4024 linear arithmetic (by automatic reflection into nat or int), including
  4025 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  4026 arithmetic type classes, supporting automatic simplification of
  4027 numerals on all operations.
  4028 
  4029 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  4030 
  4031 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  4032 
  4033 * Code generator library theories:
  4034   - Code_Integer represents HOL integers by big integer literals in target
  4035     languages.
  4036   - Code_Char represents HOL characters by character literals in target
  4037     languages.
  4038   - Code_Char_chr like Code_Char, but also offers treatment of character
  4039     codes; includes Code_Integer.
  4040   - Executable_Set allows to generate code for finite sets using lists.
  4041   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  4042     denominator).
  4043   - Executable_Real implements a subset of real numbers, namly those
  4044     representable by rational numbers.
  4045   - Efficient_Nat implements natural numbers by integers, which in general will
  4046     result in higher efficency; pattern matching with 0/Suc is eliminated;
  4047     includes Code_Integer.
  4048   - Code_Index provides an additional datatype index which is mapped to
  4049     target-language built-in integers.
  4050   - Code_Message provides an additional datatype message_string which is isomorphic to
  4051     strings; messages are mapped to target-language strings.
  4052 
  4053 * New package for inductive predicates
  4054 
  4055   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  4056 
  4057     inductive
  4058       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4059       for z_1 :: U_1 and ... and z_n :: U_m
  4060     where
  4061       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4062     | ...
  4063 
  4064   with full support for type-inference, rather than
  4065 
  4066     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4067 
  4068     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4069     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4070 
  4071     inductive "s z_1 ... z_m"
  4072     intros
  4073       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4074       ...
  4075 
  4076   For backward compatibility, there is a wrapper allowing inductive
  4077   sets to be defined with the new package via
  4078 
  4079     inductive_set
  4080       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4081       for z_1 :: U_1 and ... and z_n :: U_m
  4082     where
  4083       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4084     | ...
  4085 
  4086   or
  4087 
  4088     inductive_set
  4089       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4090       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4091       for z_1 :: U_1 and ... and z_n :: U_m
  4092     where
  4093       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4094     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4095     | ...
  4096 
  4097   if the additional syntax "p ..." is required.
  4098 
  4099   Numerous examples can be found in the subdirectories src/HOL/Auth,
  4100   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  4101 
  4102   INCOMPATIBILITIES:
  4103 
  4104   - Since declaration and definition of inductive sets or predicates
  4105     is no longer separated, abbreviations involving the newly
  4106     introduced sets or predicates must be specified together with the
  4107     introduction rules after the 'where' keyword (see above), rather
  4108     than before the actual inductive definition.
  4109 
  4110   - The variables in induction and elimination rules are now
  4111     quantified in the order of their occurrence in the introduction
  4112     rules, rather than in alphabetical order. Since this may break
  4113     some proofs, these proofs either have to be repaired, e.g. by
  4114     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  4115     statements of the form
  4116 
  4117       case (rule_i a_i_1 ... a_i_{k_i})
  4118 
  4119     or the old order of quantification has to be restored by explicitly adding
  4120     meta-level quantifiers in the introduction rules, i.e.
  4121 
  4122       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  4123 
  4124   - The format of the elimination rules is now
  4125 
  4126       p z_1 ... z_m x_1 ... x_n ==>
  4127         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4128         ==> ... ==> P
  4129 
  4130     for predicates and
  4131 
  4132       (x_1, ..., x_n) : s z_1 ... z_m ==>
  4133         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4134         ==> ... ==> P
  4135 
  4136     for sets rather than
  4137 
  4138       x : s z_1 ... z_m ==>
  4139         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  4140         ==> ... ==> P
  4141 
  4142     This may require terms in goals to be expanded to n-tuples
  4143     (e.g. using case_tac or simplification with the split_paired_all
  4144     rule) before the above elimination rule is applicable.
  4145 
  4146   - The elimination or case analysis rules for (mutually) inductive
  4147     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  4148     list of rules "p_1_..._p_k.elims" is no longer available.
  4149 
  4150 * New package "function"/"fun" for general recursive functions,
  4151 supporting mutual and nested recursion, definitions in local contexts,
  4152 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  4153 for small examples, and the separate tutorial on the function
  4154 package. The old recdef "package" is still available as before, but
  4155 users are encouraged to use the new package.
  4156 
  4157 * Method "lexicographic_order" automatically synthesizes termination
  4158 relations as lexicographic combinations of size measures. 
  4159 
  4160 * Case-expressions allow arbitrary constructor-patterns (including
  4161 "_") and take their order into account, like in functional
  4162 programming.  Internally, this is translated into nested
  4163 case-expressions; missing cases are added and mapped to the predefined
  4164 constant "undefined". In complicated cases printing may no longer show
  4165 the original input but the internal form. Lambda-abstractions allow
  4166 the same form of pattern matching: "% pat1 => e1 | ..." is an
  4167 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  4168 variable.
  4169 
  4170 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  4171 is an abbreviation for "of_nat :: nat => int". The simplification
  4172 rules for "of_nat" have been changed to work like "int" did
  4173 previously.  Potential INCOMPATIBILITY:
  4174   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  4175   - of_nat_diff and of_nat_mult are no longer default simp rules
  4176 
  4177 * Method "algebra" solves polynomial equations over (semi)rings using
  4178 Groebner bases. The (semi)ring structure is defined by locales and the
  4179 tool setup depends on that generic context. Installing the method for
  4180 a specific type involves instantiating the locale and possibly adding
  4181 declarations for computation on the coefficients.  The method is
  4182 already instantiated for natural numbers and for the axiomatic class
  4183 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  4184 CALCULEMUS 2007 for the general principles underlying this
  4185 architecture of context-aware proof-tools.
  4186 
  4187 * Method "ferrack" implements quantifier elimination over
  4188 special-purpose dense linear orders using locales (analogous to
  4189 "algebra"). The method is already installed for class
  4190 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  4191 rat, etc.
  4192 
  4193 * Former constant "List.op @" now named "List.append".  Use ML
  4194 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  4195 circumvent possible incompatibilities when working on ML level.
  4196 
  4197 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  4198 
  4199 * New function listsum :: 'a list => 'a for arbitrary monoids.
  4200 Special syntax: "SUM x <- xs. f x" (and latex variants)
  4201 
  4202 * New syntax for Haskell-like list comprehension (input only), eg.
  4203 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  4204 
  4205 * The special syntax for function "filter" has changed from [x :
  4206 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  4207 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  4208 
  4209 * [a..b] is now defined for arbitrary linear orders.  It used to be
  4210 defined on nat only, as an abbreviation for [a..<Suc b]
  4211 INCOMPATIBILITY.
  4212 
  4213 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  4214 
  4215 * New functions "sorted" and "sort" in src/HOL/List.thy.
  4216 
  4217 * New lemma collection field_simps (an extension of ring_simps) for
  4218 manipulating (in)equations involving division. Multiplies with all
  4219 denominators that can be proved to be non-zero (in equations) or
  4220 positive/negative (in inequations).
  4221 
  4222 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  4223 have been improved and renamed to ring_simps, group_simps and
  4224 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  4225 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  4226 
  4227 * Theory Library/Commutative_Ring: switched from recdef to function
  4228 package; constants add, mul, pow now curried.  Infix syntax for
  4229 algebraic operations.
  4230 
  4231 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  4232 INCOMPATIBILITY.
  4233 
  4234 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  4235 INCOMPATIBILITY.
  4236 
  4237 * HOL/records: generalised field-update to take a function on the
  4238 field rather than the new value: r(|A := x|) is translated to A_update
  4239 (K x) r The K-combinator that is internally used is called K_record.
  4240 INCOMPATIBILITY: Usage of the plain update functions has to be
  4241 adapted.
  4242  
  4243 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  4244 * x = 0, which are required for a semiring.  Richer structures do not
  4245 inherit from semiring_0 anymore, because this property is a theorem
  4246 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  4247 there is more to prove, but this is mostly trivial.
  4248 
  4249 * Class "recpower" is generalized to arbitrary monoids, not just
  4250 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  4251 commutativity or semiring properties additionally.
  4252 
  4253 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  4254 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  4255 better use 'abbreviation'.
  4256 
  4257 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  4258 
  4259 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  4260 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  4261 significant changes for setting up numeral syntax for types:
  4262   - New constants Numeral.pred and Numeral.succ instead
  4263       of former Numeral.bin_pred and Numeral.bin_succ.
  4264   - Use integer operations instead of bin_add, bin_mult and so on.
  4265   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  4266   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  4267 
  4268 See src/HOL/Integ/IntArith.thy for an example setup.
  4269 
  4270 * Command 'normal_form' computes the normal form of a term that may
  4271 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  4272 produces ``[b, c, a]'' (without proof).  This command is suitable for
  4273 heavy-duty computations because the functions are compiled to ML
  4274 first.  Correspondingly, a method "normalization" is provided.  See
  4275 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  4276 
  4277 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  4278 25 like -->); output depends on the "iff" print_mode, the default is
  4279 "A = B" (with priority 50).
  4280 
  4281 * Relations less (<) and less_eq (<=) are also available on type bool.
  4282 Modified syntax to disallow nesting without explicit parentheses,
  4283 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  4284 INCOMPATIBILITY.
  4285 
  4286 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  4287 
  4288 * Relation composition operator "op O" now has precedence 75 and binds
  4289 stronger than union and intersection. INCOMPATIBILITY.
  4290 
  4291 * The old set interval syntax "{m..n(}" (and relatives) has been
  4292 removed.  Use "{m..<n}" (and relatives) instead.
  4293 
  4294 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  4295 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  4296 ``declare [[simproc del: neq]]''.
  4297 
  4298 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  4299 True/False.
  4300 
  4301 * Theorem Cons_eq_map_conv no longer declared as "simp".
  4302 
  4303 * Theorem setsum_mult renamed to setsum_right_distrib.
  4304 
  4305 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  4306 ``rule'' method.
  4307 
  4308 * Reimplemented methods "sat" and "satx", with several improvements:
  4309 goals no longer need to be stated as "<prems> ==> False", equivalences
  4310 (i.e. "=" on type bool) are handled, variable names of the form
  4311 "lit_<n>" are no longer reserved, significant speedup.
  4312 
  4313 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  4314 zChaff is still supported as well.
  4315 
  4316 * 'inductive' and 'datatype': provide projections of mutual rules,
  4317 bundled as foo_bar.inducts;
  4318 
  4319 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  4320 Library.
  4321 
  4322 * Library: moved theory Accessible_Part to main HOL.
  4323 
  4324 * Library: added theory Coinductive_List of potentially infinite lists
  4325 as greatest fixed-point.
  4326 
  4327 * Library: added theory AssocList which implements (finite) maps as
  4328 association lists.
  4329 
  4330 * Method "evaluation" solves goals (i.e. a boolean expression)
  4331 efficiently by compiling it to ML.  The goal is "proved" (via an
  4332 oracle) if it evaluates to True.
  4333 
  4334 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  4335 also when invoked by the simplifier.  This results in the Simplifier
  4336 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  4337 Configuration option fast_arith_split_limit=0 recovers the old
  4338 behavior.
  4339 
  4340 * Support for hex (0x20) and binary (0b1001) numerals.
  4341 
  4342 * New method: reify eqs (t), where eqs are equations for an
  4343 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  4344 parameter, computes a term s::'b and a list xs::'a list and proves the
  4345 theorem I xs s = t. This is also known as reification or quoting. The
  4346 resulting theorem is applied to the subgoal to substitute t with I xs
  4347 s.  If t is omitted, the subgoal itself is reified.
  4348 
  4349 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  4350 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  4351 where f is supposed to be a computable function (in the sense of code
  4352 generattion). The method uses reify to compute s and xs as above then
  4353 applies corr_thm and uses normalization by evaluation to "prove" f s =
  4354 r and finally gets the theorem t = r, which is again applied to the
  4355 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  4356 
  4357 * Reflection: Automatic reification now handels binding, an example is
  4358 available in src/HOL/ex/ReflectionEx.thy
  4359 
  4360 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  4361 command 'statespace' that is similar to 'record', but introduces an
  4362 abstract specification based on the locale infrastructure instead of
  4363 HOL types.  This leads to extra flexibility in composing state spaces,
  4364 in particular multiple inheritance and renaming of components.
  4365 
  4366 
  4367 *** HOL-Complex ***
  4368 
  4369 * Hyperreal: Functions root and sqrt are now defined on negative real
  4370 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  4371 Nonnegativity side conditions have been removed from many lemmas, so
  4372 that more subgoals may now be solved by simplification; potential
  4373 INCOMPATIBILITY.
  4374 
  4375 * Real: new type classes formalize real normed vector spaces and
  4376 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  4377 and norm :: 'a => real.
  4378 
  4379 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  4380 reals into other types. The overloaded constant Reals :: 'a set is now
  4381 defined as range of_real; potential INCOMPATIBILITY.
  4382 
  4383 * Real: proper support for ML code generation, including 'quickcheck'.
  4384 Reals are implemented as arbitrary precision rationals.
  4385 
  4386 * Hyperreal: Several constants that previously worked only for the
  4387 reals have been generalized, so they now work over arbitrary vector
  4388 spaces. Type annotations may need to be added in some cases; potential
  4389 INCOMPATIBILITY.
  4390 
  4391   Infinitesimal  :: ('a::real_normed_vector) star set
  4392   HFinite        :: ('a::real_normed_vector) star set
  4393   HInfinite      :: ('a::real_normed_vector) star set
  4394   approx         :: ('a::real_normed_vector) star => 'a star => bool
  4395   monad          :: ('a::real_normed_vector) star => 'a star set
  4396   galaxy         :: ('a::real_normed_vector) star => 'a star set
  4397   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  4398   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  4399   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  4400   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  4401   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  4402   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  4403   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  4404   sgn            :: 'a::real_normed_vector => 'a
  4405   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  4406 
  4407 * Complex: Some complex-specific constants are now abbreviations for
  4408 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  4409 hnorm.  Other constants have been entirely removed in favor of the
  4410 polymorphic versions (INCOMPATIBILITY):
  4411 
  4412   approx        <-- capprox
  4413   HFinite       <-- CFinite
  4414   HInfinite     <-- CInfinite
  4415   Infinitesimal <-- CInfinitesimal
  4416   monad         <-- cmonad
  4417   galaxy        <-- cgalaxy
  4418   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  4419   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  4420   (ns)deriv     <-- (ns)cderiv
  4421 
  4422 
  4423 *** HOL-Algebra ***
  4424 
  4425 * Formalisation of ideals and the quotient construction over rings.
  4426 
  4427 * Order and lattice theory no longer based on records.
  4428 INCOMPATIBILITY.
  4429 
  4430 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  4431 greatest_closed.  INCOMPATIBILITY.
  4432 
  4433 * Method algebra is now set up via an attribute.  For examples see
  4434 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  4435 of algebraic structures.
  4436 
  4437 * Renamed theory CRing to Ring.
  4438 
  4439 
  4440 *** HOL-Nominal ***
  4441 
  4442 * Substantial, yet incomplete support for nominal datatypes (binding
  4443 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  4444 src/HOL/Nominal/Examples.  Prospective users should consult
  4445 http://isabelle.in.tum.de/nominal/
  4446 
  4447 
  4448 *** ML ***
  4449 
  4450 * ML basics: just one true type int, which coincides with IntInf.int
  4451 (even on SML/NJ).
  4452 
  4453 * ML within Isar: antiquotations allow to embed statically-checked
  4454 formal entities in the source, referring to the context available at
  4455 compile-time.  For example:
  4456 
  4457 ML {* @{sort "{zero,one}"} *}
  4458 ML {* @{typ "'a => 'b"} *}
  4459 ML {* @{term "%x. x"} *}
  4460 ML {* @{prop "x == y"} *}
  4461 ML {* @{ctyp "'a => 'b"} *}
  4462 ML {* @{cterm "%x. x"} *}
  4463 ML {* @{cprop "x == y"} *}
  4464 ML {* @{thm asm_rl} *}
  4465 ML {* @{thms asm_rl} *}
  4466 ML {* @{type_name c} *}
  4467 ML {* @{type_syntax c} *}
  4468 ML {* @{const_name c} *}
  4469 ML {* @{const_syntax c} *}
  4470 ML {* @{context} *}
  4471 ML {* @{theory} *}
  4472 ML {* @{theory Pure} *}
  4473 ML {* @{theory_ref} *}
  4474 ML {* @{theory_ref Pure} *}
  4475 ML {* @{simpset} *}
  4476 ML {* @{claset} *}
  4477 ML {* @{clasimpset} *}
  4478 
  4479 The same works for sources being ``used'' within an Isar context.
  4480 
  4481 * ML in Isar: improved error reporting; extra verbosity with
  4482 ML_Context.trace enabled.
  4483 
  4484 * Pure/General/table.ML: the join operations now works via exceptions
  4485 DUP/SAME instead of type option. This is simpler in simple cases, and
  4486 admits slightly more efficient complex applications.
  4487 
  4488 * Pure: 'advanced' translation functions (parse_translation etc.) now
  4489 use Context.generic instead of just theory.
  4490 
  4491 * Pure: datatype Context.generic joins theory/Proof.context and
  4492 provides some facilities for code that works in either kind of
  4493 context, notably GenericDataFun for uniform theory and proof data.
  4494 
  4495 * Pure: simplified internal attribute type, which is now always
  4496 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  4497 local (Proof.context) attributes have been discontinued, while
  4498 minimizing code duplication. Thm.rule_attribute and
  4499 Thm.declaration_attribute build canonical attributes; see also structure
  4500 Context for further operations on Context.generic, notably
  4501 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  4502 declarations and definitions.
  4503 
  4504 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  4505 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  4506 init only required for impure data. INCOMPATIBILITY: empty really need
  4507 to be empty (no dependencies on theory content!)
  4508 
  4509 * Pure/kernel: consts certification ignores sort constraints given in
  4510 signature declarations. (This information is not relevant to the
  4511 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  4512 potential INCOMPATIBILITY.
  4513 
  4514 * Pure: axiomatic type classes are now purely definitional, with
  4515 explicit proofs of class axioms and super class relations performed
  4516 internally. See Pure/axclass.ML for the main internal interfaces --
  4517 notably AxClass.define_class supercedes AxClass.add_axclass, and
  4518 AxClass.axiomatize_class/classrel/arity supersede
  4519 Sign.add_classes/classrel/arities.
  4520 
  4521 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  4522 global/local versions on theory vs. Proof.context have been
  4523 discontinued; Attrib.syntax and Method.syntax have been adapted
  4524 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  4525 attributes, methods, etc.
  4526 
  4527 * Pure: several functions of signature "... -> theory -> theory * ..."
  4528 have been reoriented to "... -> theory -> ... * theory" in order to
  4529 allow natural usage in combination with the ||>, ||>>, |-> and
  4530 fold_map combinators.
  4531 
  4532 * Pure: official theorem names (closed derivations) and additional
  4533 comments (tags) are now strictly separate.  Name hints -- which are
  4534 maintained as tags -- may be attached any time without affecting the
  4535 derivation.
  4536 
  4537 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  4538 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  4539 achieve the old behaviour.
  4540 
  4541 * Pure: the "Goal" constant is now called "prop", supporting a
  4542 slightly more general idea of ``protecting'' meta-level rule
  4543 statements.
  4544 
  4545 * Pure: Logic.(un)varify only works in a global context, which is now
  4546 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  4547 Logic.legacy_(un)varify as temporary workaround.
  4548 
  4549 * Pure: structure Name provides scalable operations for generating
  4550 internal variable names, notably Name.variants etc.  This replaces
  4551 some popular functions from term.ML:
  4552 
  4553   Term.variant		->  Name.variant
  4554   Term.variantlist	->  Name.variant_list
  4555   Term.invent_names	->  Name.invent_list
  4556 
  4557 Note that low-level renaming rarely occurs in new code -- operations
  4558 from structure Variable are used instead (see below).
  4559 
  4560 * Pure: structure Variable provides fundamental operations for proper
  4561 treatment of fixed/schematic variables in a context.  For example,
  4562 Variable.import introduces fixes for schematics of given facts and
  4563 Variable.export reverses the effect (up to renaming) -- this replaces
  4564 various freeze_thaw operations.
  4565 
  4566 * Pure: structure Goal provides simple interfaces for
  4567 init/conclude/finish and tactical prove operations (replacing former
  4568 Tactic.prove).  Goal.prove is the canonical way to prove results
  4569 within a given context; Goal.prove_global is a degraded version for
  4570 theory level goals, including a global Drule.standard.  Note that
  4571 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  4572 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  4573 in a locale context).
  4574 
  4575 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  4576 and type checking (Syntax.check_term etc.), with common combinations
  4577 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  4578 which are considered legacy and await removal.
  4579 
  4580 * Pure/Syntax: generic interfaces for type unchecking
  4581 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  4582 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  4583 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  4584 available for convenience, but refer to the very same operations using
  4585 a mere theory instead of a full context.
  4586 
  4587 * Isar: simplified treatment of user-level errors, using exception
  4588 ERROR of string uniformly.  Function error now merely raises ERROR,
  4589 without any side effect on output channels.  The Isar toplevel takes
  4590 care of proper display of ERROR exceptions.  ML code may use plain
  4591 handle/can/try; cat_error may be used to concatenate errors like this:
  4592 
  4593   ... handle ERROR msg => cat_error msg "..."
  4594 
  4595 Toplevel ML code (run directly or through the Isar toplevel) may be
  4596 embedded into the Isar toplevel with exception display/debug like
  4597 this:
  4598 
  4599   Isar.toplevel (fn () => ...)
  4600 
  4601 INCOMPATIBILITY, removed special transform_error facilities, removed
  4602 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  4603 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  4604 -- use plain ERROR instead.
  4605 
  4606 * Isar: theory setup now has type (theory -> theory), instead of a
  4607 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  4608 
  4609 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  4610 ProofContext.debug/verbose flags.
  4611 
  4612 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  4613 theory before entering a proof state.  Transactions now always see a
  4614 quasi-functional intermediate checkpoint, both in interactive and
  4615 batch mode.
  4616 
  4617 * Isar: simplified interfaces for outer syntax.  Renamed
  4618 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  4619 OuterSyntax.add_parsers -- this functionality is now included in
  4620 OuterSyntax.command etc.  INCOMPATIBILITY.
  4621 
  4622 * Simplifier: the simpset of a running simplification process now
  4623 contains a proof context (cf. Simplifier.the_context), which is the
  4624 very context that the initial simpset has been retrieved from (by
  4625 simpset_of/local_simpset_of).  Consequently, all plug-in components
  4626 (solver, looper etc.) may depend on arbitrary proof data.
  4627 
  4628 * Simplifier.inherit_context inherits the proof context (plus the
  4629 local bounds) of the current simplification process; any simproc
  4630 etc. that calls the Simplifier recursively should do this!  Removed
  4631 former Simplifier.inherit_bounds, which is already included here --
  4632 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  4633 specify an explicit context using Simplifier.context/theory_context.
  4634 
  4635 * Simplifier/Classical Reasoner: more abstract interfaces
  4636 change_simpset/claset for modifying the simpset/claset reference of a
  4637 theory; raw versions simpset/claset_ref etc. have been discontinued --
  4638 INCOMPATIBILITY.
  4639 
  4640 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  4641 "Trueprop" etc.
  4642 
  4643 
  4644 *** System ***
  4645 
  4646 * settings: the default heap location within ISABELLE_HOME_USER now
  4647 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  4648 Isabelle installations.
  4649 
  4650 * isabelle-process: option -S (secure mode) disables some critical
  4651 operations, notably runtime compilation and evaluation of ML source
  4652 code.
  4653 
  4654 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  4655 
  4656 * Support for parallel execution, using native multicore support of
  4657 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  4658 independent theories, according to the given theory header
  4659 specifications. The maximum number of worker threads is specified via
  4660 usedir option -M or the "max-threads" setting in Proof General. A
  4661 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  4662 to 6 on a 8-core machine.  User-code needs to observe certain
  4663 guidelines for thread-safe programming, see appendix A in the Isar
  4664 Implementation manual.
  4665 
  4666 
  4667 
  4668 New in Isabelle2005 (October 2005)
  4669 ----------------------------------
  4670 
  4671 *** General ***
  4672 
  4673 * Theory headers: the new header syntax for Isar theories is
  4674 
  4675   theory <name>
  4676   imports <theory1> ... <theoryN>
  4677   uses <file1> ... <fileM>
  4678   begin
  4679 
  4680 where the 'uses' part is optional.  The previous syntax
  4681 
  4682   theory <name> = <theory1> + ... + <theoryN>:
  4683 
  4684 will disappear in the next release.  Use isatool fixheaders to convert
  4685 existing theory files.  Note that there is no change in ancient
  4686 non-Isar theories now, but these will disappear soon.
  4687 
  4688 * Theory loader: parent theories can now also be referred to via
  4689 relative and absolute paths.
  4690 
  4691 * Command 'find_theorems' searches for a list of criteria instead of a
  4692 list of constants. Known criteria are: intro, elim, dest, name:string,
  4693 simp:term, and any term. Criteria can be preceded by '-' to select
  4694 theorems that do not match. Intro, elim, dest select theorems that
  4695 match the current goal, name:s selects theorems whose fully qualified
  4696 name contain s, and simp:term selects all simplification rules whose
  4697 lhs match term.  Any other term is interpreted as pattern and selects
  4698 all theorems matching the pattern. Available in ProofGeneral under
  4699 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  4700 
  4701   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  4702 
  4703 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  4704 matching the current goal as introduction rule and not having "HOL."
  4705 in their name (i.e. not being defined in theory HOL).
  4706 
  4707 * Command 'thms_containing' has been discontinued in favour of
  4708 'find_theorems'; INCOMPATIBILITY.
  4709 
  4710 * Communication with Proof General is now 8bit clean, which means that
  4711 Unicode text in UTF-8 encoding may be used within theory texts (both
  4712 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4713 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4714 
  4715   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4716   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4717 
  4718 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4719 Classical Reasoner.  Typical big applications run around 2 times
  4720 faster.
  4721 
  4722 
  4723 *** Document preparation ***
  4724 
  4725 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4726 of raw sources.  Only those symbols that do not require additional
  4727 LaTeX packages (depending on comments in isabellesym.sty) are
  4728 displayed properly, everything else is left verbatim.  isatool display
  4729 and isatool print are used as front ends (these are subject to the
  4730 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4731 
  4732 * Command tags control specific markup of certain regions of text,
  4733 notably folding and hiding.  Predefined tags include "theory" (for
  4734 theory begin and end), "proof" for proof commands, and "ML" for
  4735 commands involving ML code; the additional tags "visible" and
  4736 "invisible" are unused by default.  Users may give explicit tag
  4737 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4738 interpretation of tags is determined by the LaTeX job during document
  4739 preparation: see option -V of isatool usedir, or options -n and -t of
  4740 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4741 \isadroptag.
  4742 
  4743 Several document versions may be produced at the same time via isatool
  4744 usedir (the generated index.html will link all of them).  Typical
  4745 specifications include ''-V document=theory,proof,ML'' to present
  4746 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4747 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4748 these parts without any formal replacement text.  The Isabelle site
  4749 default settings produce ''document'' and ''outline'' versions as
  4750 specified above.
  4751 
  4752 * Several new antiquotations:
  4753 
  4754   @{term_type term} prints a term with its type annotated;
  4755 
  4756   @{typeof term} prints the type of a term;
  4757 
  4758   @{const const} is the same as @{term const}, but checks that the
  4759   argument is a known logical constant;
  4760 
  4761   @{term_style style term} and @{thm_style style thm} print a term or
  4762   theorem applying a "style" to it
  4763 
  4764   @{ML text}
  4765 
  4766 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4767 definitions, equations, inequations etc., 'concl' printing only the
  4768 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4769 to print the specified premise.  TermStyle.add_style provides an ML
  4770 interface for introducing further styles.  See also the "LaTeX Sugar"
  4771 document practical applications.  The ML antiquotation prints
  4772 type-checked ML expressions verbatim.
  4773 
  4774 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4775 and 'text' support optional locale specification '(in loc)', which
  4776 specifies the default context for interpreting antiquotations.  For
  4777 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4778 
  4779 * Option 'locale=NAME' of antiquotations specifies an alternative
  4780 context interpreting the subsequent argument.  For example: @{thm
  4781 [locale=lattice] inf_assoc}.
  4782 
  4783 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4784 a proof context.
  4785 
  4786 * Proper output of antiquotations for theory commands involving a
  4787 proof context (such as 'locale' or 'theorem (in loc) ...').
  4788 
  4789 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4790 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4791 
  4792 * isatool usedir: new option -C (default true) controls whether option
  4793 -D should include a copy of the original document directory; -C false
  4794 prevents unwanted effects such as copying of administrative CVS data.
  4795 
  4796 
  4797 *** Pure ***
  4798 
  4799 * Considerably improved version of 'constdefs' command.  Now performs
  4800 automatic type-inference of declared constants; additional support for
  4801 local structure declarations (cf. locales and HOL records), see also
  4802 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4803 sequential dependencies of definitions within a single 'constdefs'
  4804 section; moreover, the declared name needs to be an identifier.  If
  4805 all fails, consider to fall back on 'consts' and 'defs' separately.
  4806 
  4807 * Improved indexed syntax and implicit structures.  First of all,
  4808 indexed syntax provides a notational device for subscripted
  4809 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4810 expressions.  Secondly, in a local context with structure
  4811 declarations, number indexes \<^sub>n or the empty index (default
  4812 number 1) refer to a certain fixed variable implicitly; option
  4813 show_structs controls printing of implicit structures.  Typical
  4814 applications of these concepts involve record types and locales.
  4815 
  4816 * New command 'no_syntax' removes grammar declarations (and
  4817 translations) resulting from the given syntax specification, which is
  4818 interpreted in the same manner as for the 'syntax' command.
  4819 
  4820 * 'Advanced' translation functions (parse_translation etc.) may depend
  4821 on the signature of the theory context being presently used for
  4822 parsing/printing, see also isar-ref manual.
  4823 
  4824 * Improved 'oracle' command provides a type-safe interface to turn an
  4825 ML expression of type theory -> T -> term into a primitive rule of
  4826 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4827 is already included here); see also FOL/ex/IffExample.thy;
  4828 INCOMPATIBILITY.
  4829 
  4830 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4831 before); "cI" is no longer bound, use "c.intro" instead.
  4832 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4833 axclasses vs. locales.
  4834 
  4835 * Improved internal renaming of symbolic identifiers -- attach primes
  4836 instead of base 26 numbers.
  4837 
  4838 * New flag show_question_marks controls printing of leading question
  4839 marks in schematic variable names.
  4840 
  4841 * In schematic variable names, *any* symbol following \<^isub> or
  4842 \<^isup> is now treated as part of the base name.  For example, the
  4843 following works without printing of awkward ".0" indexes:
  4844 
  4845   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4846     by simp
  4847 
  4848 * Inner syntax includes (*(*nested*) comments*).
  4849 
  4850 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4851 annotations as "(00...)".
  4852 
  4853 * Clear separation of logical types and nonterminals, where the latter
  4854 may only occur in 'syntax' specifications or type abbreviations.
  4855 Before that distinction was only partially implemented via type class
  4856 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4857 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4858 exotic syntax specifications may require further adaption
  4859 (e.g. Cube/Cube.thy).
  4860 
  4861 * Removed obsolete type class "logic", use the top sort {} instead.
  4862 Note that non-logical types should be declared as 'nonterminals'
  4863 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4864 specifications.
  4865 
  4866 * Attributes 'induct' and 'cases': type or set names may now be
  4867 locally fixed variables as well.
  4868 
  4869 * Simplifier: can now control the depth to which conditional rewriting
  4870 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4871 Limit.
  4872 
  4873 * Simplifier: simplification procedures may now take the current
  4874 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4875 interface), which is very useful for calling the Simplifier
  4876 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4877 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4878 low-level mk_simproc no longer applies Logic.varify internally, to
  4879 allow for use in a context of fixed variables.
  4880 
  4881 * thin_tac now works even if the assumption being deleted contains !!
  4882 or ==>.  More generally, erule now works even if the major premise of
  4883 the elimination rule contains !! or ==>.
  4884 
  4885 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4886 
  4887 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4888 from Pure, which contains all common declarations already.  Both
  4889 theories are defined via plain Isabelle/Isar .thy files.
  4890 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4891 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4892 use isatool fixcpure to adapt your theory and ML sources.
  4893 
  4894 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4895 selections of theorems in named facts via index ranges.
  4896 
  4897 * 'print_theorems': in theory mode, really print the difference
  4898 wrt. the last state (works for interactive theory development only),
  4899 in proof mode print all local facts (cf. 'print_facts');
  4900 
  4901 * 'hide': option '(open)' hides only base names.
  4902 
  4903 * More efficient treatment of intermediate checkpoints in interactive
  4904 theory development.
  4905 
  4906 * Code generator is now invoked via code_module (incremental code
  4907 generation) and code_library (modular code generation, ML structures
  4908 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4909 must be quoted when used as identifiers.
  4910 
  4911 * New 'value' command for reading, evaluating and printing terms using
  4912 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4913 quoted when used as identifier.
  4914 
  4915 
  4916 *** Locales ***
  4917 
  4918 * New commands for the interpretation of locale expressions in
  4919 theories (1), locales (2) and proof contexts (3).  These generate
  4920 proof obligations from the expression specification.  After the
  4921 obligations have been discharged, theorems of the expression are added
  4922 to the theory, target locale or proof context.  The synopsis of the
  4923 commands is a follows:
  4924 
  4925   (1) interpretation expr inst
  4926   (2) interpretation target < expr
  4927   (3) interpret expr inst
  4928 
  4929 Interpretation in theories and proof contexts require a parameter
  4930 instantiation of terms from the current context.  This is applied to
  4931 specifications and theorems of the interpreted expression.
  4932 Interpretation in locales only permits parameter renaming through the
  4933 locale expression.  Interpretation is smart in that interpretations
  4934 that are active already do not occur in proof obligations, neither are
  4935 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4936 inspect active interpretations of a particular locale.  For details,
  4937 see the Isar Reference manual.  Examples can be found in
  4938 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4939 
  4940 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4941 'interpret' instead.
  4942 
  4943 * New context element 'constrains' for adding type constraints to
  4944 parameters.
  4945 
  4946 * Context expressions: renaming of parameters with syntax
  4947 redeclaration.
  4948 
  4949 * Locale declaration: 'includes' disallowed.
  4950 
  4951 * Proper static binding of attribute syntax -- i.e. types / terms /
  4952 facts mentioned as arguments are always those of the locale definition
  4953 context, independently of the context of later invocations.  Moreover,
  4954 locale operations (renaming and type / term instantiation) are applied
  4955 to attribute arguments as expected.
  4956 
  4957 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4958 actual attributes; rare situations may require Attrib.attribute to
  4959 embed those attributes into Attrib.src that lack concrete syntax.
  4960 Attribute implementations need to cooperate properly with the static
  4961 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4962 Attrib.XXX_thm etc. already do the right thing without further
  4963 intervention.  Only unusual applications -- such as "where" or "of"
  4964 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4965 on the context and the facts involved -- may have to assign parsed
  4966 values to argument tokens explicitly.
  4967 
  4968 * Changed parameter management in theorem generation for long goal
  4969 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4970 theorem statement in rare situations.
  4971 
  4972 * Locale inspection command 'print_locale' omits notes elements.  Use
  4973 'print_locale!' to have them included in the output.
  4974 
  4975 
  4976 *** Provers ***
  4977 
  4978 * Provers/hypsubst.ML: improved version of the subst method, for
  4979 single-step rewriting: it now works in bound variable contexts. New is
  4980 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  4981 rewrite a different subterm than the original subst method, which is
  4982 still available as 'simplesubst'.
  4983 
  4984 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  4985 and quasi orders.
  4986 
  4987 * Provers/trancl.ML: new transitivity reasoner for transitive and
  4988 reflexive-transitive closure of relations.
  4989 
  4990 * Provers/blast.ML: new reference depth_limit to make blast's depth
  4991 limit (previously hard-coded with a value of 20) user-definable.
  4992 
  4993 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  4994 is peformed already.  Object-logics merely need to finish their
  4995 initial simpset configuration as before.  INCOMPATIBILITY.
  4996 
  4997 
  4998 *** HOL ***
  4999 
  5000 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  5001 
  5002   syntax (epsilon)
  5003     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  5004 
  5005 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  5006 and x-symbol; use option '-m epsilon' to get it actually printed.
  5007 Moreover, the mathematically important symbolic identifier \<epsilon>
  5008 becomes available as variable, constant etc.  INCOMPATIBILITY,
  5009 
  5010 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  5011 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  5012 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  5013 support corresponding Isar calculations.
  5014 
  5015 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  5016 instead of ":".
  5017 
  5018 * theory SetInterval: changed the syntax for open intervals:
  5019 
  5020   Old       New
  5021   {..n(}    {..<n}
  5022   {)n..}    {n<..}
  5023   {m..n(}   {m..<n}
  5024   {)m..n}   {m<..n}
  5025   {)m..n(}  {m<..<n}
  5026 
  5027 The old syntax is still supported but will disappear in the next
  5028 release.  For conversion use the following Emacs search and replace
  5029 patterns (these are not perfect but work quite well):
  5030 
  5031   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  5032   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  5033 
  5034 * Theory Commutative_Ring (in Library): method comm_ring for proving
  5035 equalities in commutative rings; method 'algebra' provides a generic
  5036 interface.
  5037 
  5038 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  5039 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  5040 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  5041 be a tuple pattern.
  5042 
  5043 Some new syntax forms are available:
  5044 
  5045   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  5046   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  5047   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  5048   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  5049 
  5050 The latter form "\<Sum>x < k. e" used to be based on a separate
  5051 function "Summation", which has been discontinued.
  5052 
  5053 * theory Finite_Set: in structured induction proofs, the insert case
  5054 is now 'case (insert x F)' instead of the old counterintuitive 'case
  5055 (insert F x)'.
  5056 
  5057 * The 'refute' command has been extended to support a much larger
  5058 fragment of HOL, including axiomatic type classes, constdefs and
  5059 typedefs, inductive datatypes and recursion.
  5060 
  5061 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  5062 Requires zChaff with proof generation to be installed.  See
  5063 HOL/ex/SAT_Examples.thy for examples.
  5064 
  5065 * Datatype induction via method 'induct' now preserves the name of the
  5066 induction variable. For example, when proving P(xs::'a list) by
  5067 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  5068 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  5069 in unstructured proof scripts.
  5070 
  5071 * Reworked implementation of records.  Improved scalability for
  5072 records with many fields, avoiding performance problems for type
  5073 inference. Records are no longer composed of nested field types, but
  5074 of nested extension types. Therefore the record type only grows linear
  5075 in the number of extensions and not in the number of fields.  The
  5076 top-level (users) view on records is preserved.  Potential
  5077 INCOMPATIBILITY only in strange cases, where the theory depends on the
  5078 old record representation. The type generated for a record is called
  5079 <record_name>_ext_type.
  5080 
  5081 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  5082 proofs triggered by a record definition or a simproc (if
  5083 quick_and_dirty is enabled).  Definitions of large records can take
  5084 quite long.
  5085 
  5086 New simproc record_upd_simproc for simplification of multiple record
  5087 updates enabled by default.  Moreover, trivial updates are also
  5088 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  5089 occasionally, since simplification is more powerful by default.
  5090 
  5091 * typedef: proper support for polymorphic sets, which contain extra
  5092 type-variables in the term.
  5093 
  5094 * Simplifier: automatically reasons about transitivity chains
  5095 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  5096 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  5097 old proofs break occasionally as simplification may now solve more
  5098 goals than previously.
  5099 
  5100 * Simplifier: converts x <= y into x = y if assumption y <= x is
  5101 present.  Works for all partial orders (class "order"), in particular
  5102 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  5103 just like y <= x.
  5104 
  5105 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  5106 bound variable or a constant then the let is unfolded.  Otherwise
  5107 first a is simplified to b, and then f b is simplified to g. If
  5108 possible we abstract b from g arriving at "let x = b in h x",
  5109 otherwise we unfold the let and arrive at g.  The simproc can be
  5110 enabled/disabled by the reference use_let_simproc.  Potential
  5111 INCOMPATIBILITY since simplification is more powerful by default.
  5112 
  5113 * Classical reasoning: the meson method now accepts theorems as arguments.
  5114 
  5115 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  5116 jobs to provide advice on the provability of subgoals.
  5117 
  5118 * Theory OrderedGroup and Ring_and_Field: various additions and
  5119 improvements to faciliate calculations involving equalities and
  5120 inequalities.
  5121 
  5122 The following theorems have been eliminated or modified
  5123 (INCOMPATIBILITY):
  5124 
  5125   abs_eq             now named abs_of_nonneg
  5126   abs_of_ge_0        now named abs_of_nonneg
  5127   abs_minus_eq       now named abs_of_nonpos
  5128   imp_abs_id         now named abs_of_nonneg
  5129   imp_abs_neg_id     now named abs_of_nonpos
  5130   mult_pos           now named mult_pos_pos
  5131   mult_pos_le        now named mult_nonneg_nonneg
  5132   mult_pos_neg_le    now named mult_nonneg_nonpos
  5133   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  5134   mult_neg           now named mult_neg_neg
  5135   mult_neg_le        now named mult_nonpos_nonpos
  5136 
  5137 * The following lemmas in Ring_and_Field have been added to the simplifier:
  5138      
  5139      zero_le_square
  5140      not_square_less_zero 
  5141 
  5142   The following lemmas have been deleted from Real/RealPow:
  5143   
  5144      realpow_zero_zero
  5145      realpow_two
  5146      realpow_less
  5147      zero_le_power
  5148      realpow_two_le
  5149      abs_realpow_two
  5150      realpow_two_abs     
  5151 
  5152 * Theory Parity: added rules for simplifying exponents.
  5153 
  5154 * Theory List:
  5155 
  5156 The following theorems have been eliminated or modified
  5157 (INCOMPATIBILITY):
  5158 
  5159   list_all_Nil       now named list_all.simps(1)
  5160   list_all_Cons      now named list_all.simps(2)
  5161   list_all_conv      now named list_all_iff
  5162   set_mem_eq         now named mem_iff
  5163 
  5164 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  5165 asymptotic "big O" calculations.  See the notes in BigO.thy.
  5166 
  5167 
  5168 *** HOL-Complex ***
  5169 
  5170 * Theory RealDef: better support for embedding natural numbers and
  5171 integers in the reals.
  5172 
  5173 The following theorems have been eliminated or modified
  5174 (INCOMPATIBILITY):
  5175 
  5176   exp_ge_add_one_self  now requires no hypotheses
  5177   real_of_int_add      reversed direction of equality (use [symmetric])
  5178   real_of_int_minus    reversed direction of equality (use [symmetric])
  5179   real_of_int_diff     reversed direction of equality (use [symmetric])
  5180   real_of_int_mult     reversed direction of equality (use [symmetric])
  5181 
  5182 * Theory RComplete: expanded support for floor and ceiling functions.
  5183 
  5184 * Theory Ln is new, with properties of the natural logarithm
  5185 
  5186 * Hyperreal: There is a new type constructor "star" for making
  5187 nonstandard types.  The old type names are now type synonyms:
  5188 
  5189   hypreal = real star
  5190   hypnat = nat star
  5191   hcomplex = complex star
  5192 
  5193 * Hyperreal: Many groups of similarly-defined constants have been
  5194 replaced by polymorphic versions (INCOMPATIBILITY):
  5195 
  5196   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  5197 
  5198   starset      <-- starsetNat, starsetC
  5199   *s*          <-- *sNat*, *sc*
  5200   starset_n    <-- starsetNat_n, starsetC_n
  5201   *sn*         <-- *sNatn*, *scn*
  5202   InternalSets <-- InternalNatSets, InternalCSets
  5203 
  5204   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  5205   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  5206   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  5207   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  5208   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  5209 
  5210 * Hyperreal: Many type-specific theorems have been removed in favor of
  5211 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  5212 
  5213   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  5214   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  5215   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  5216   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  5217   right_minus <-- hypreal_add_minus
  5218   left_minus <-- {hypreal,hcomplex}_add_minus_left
  5219   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  5220   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  5221   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  5222   mult_1_right <-- hcomplex_mult_one_right
  5223   mult_zero_left <-- hcomplex_mult_zero_left
  5224   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  5225   right_distrib <-- hypnat_add_mult_distrib2
  5226   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  5227   right_inverse <-- hypreal_mult_inverse
  5228   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  5229   order_refl <-- {hypreal,hypnat}_le_refl
  5230   order_trans <-- {hypreal,hypnat}_le_trans
  5231   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  5232   order_less_le <-- {hypreal,hypnat}_less_le
  5233   linorder_linear <-- {hypreal,hypnat}_le_linear
  5234   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  5235   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  5236   add_nonneg_nonneg <-- hypreal_le_add_order
  5237 
  5238 * Hyperreal: Separate theorems having to do with type-specific
  5239 versions of constants have been merged into theorems that apply to the
  5240 new polymorphic constants (INCOMPATIBILITY):
  5241 
  5242   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  5243   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  5244   STAR_Un <-- {STAR,NatStar,STARC}_Un
  5245   STAR_Int <-- {STAR,NatStar,STARC}_Int
  5246   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  5247   STAR_subset <-- {STAR,NatStar,STARC}_subset
  5248   STAR_mem <-- {STAR,NatStar,STARC}_mem
  5249   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  5250   STAR_diff <-- {STAR,STARC}_diff
  5251   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  5252     STARC_hcomplex_of_complex}_image_subset
  5253   starset_n_Un <-- starset{Nat,C}_n_Un
  5254   starset_n_Int <-- starset{Nat,C}_n_Int
  5255   starset_n_Compl <-- starset{Nat,C}_n_Compl
  5256   starset_n_diff <-- starset{Nat,C}_n_diff
  5257   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  5258   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  5259   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  5260   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  5261   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  5262   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  5263   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  5264   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  5265   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  5266   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  5267   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  5268   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  5269   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  5270   starfun_diff <-- starfun{C,RC,CR}_diff
  5271   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  5272   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  5273   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  5274   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  5275   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  5276   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  5277   starfun_Id <-- starfunC_Id
  5278   starfun_approx <-- starfun{Nat,CR}_approx
  5279   starfun_capprox <-- starfun{C,RC}_capprox
  5280   starfun_abs <-- starfunNat_rabs
  5281   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  5282   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  5283   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  5284   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  5285   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  5286   starfun_add_approx <-- starfunCR_add_approx
  5287   starfun_inverse_inverse <-- starfunC_inverse_inverse
  5288   starfun_divide <-- starfun{C,CR,RC}_divide
  5289   starfun_n <-- starfun{Nat,C}_n
  5290   starfun_n_mult <-- starfun{Nat,C}_n_mult
  5291   starfun_n_add <-- starfun{Nat,C}_n_add
  5292   starfun_n_add_minus <-- starfunNat_n_add_minus
  5293   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  5294   starfun_n_minus <-- starfun{Nat,C}_n_minus
  5295   starfun_n_eq <-- starfun{Nat,C}_n_eq
  5296 
  5297   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  5298   star_n_minus <-- {hypreal,hcomplex}_minus
  5299   star_n_diff <-- {hypreal,hcomplex}_diff
  5300   star_n_mult <-- {hypreal,hcomplex}_mult
  5301   star_n_inverse <-- {hypreal,hcomplex}_inverse
  5302   star_n_le <-- {hypreal,hypnat}_le
  5303   star_n_less <-- {hypreal,hypnat}_less
  5304   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  5305   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  5306   star_n_abs <-- hypreal_hrabs
  5307   star_n_divide <-- hcomplex_divide
  5308 
  5309   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  5310   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  5311   star_of_diff <-- hypreal_of_real_diff
  5312   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  5313   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  5314   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  5315   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  5316   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  5317   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  5318   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  5319   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  5320   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  5321   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  5322   star_of_number_of <-- {hypreal,hcomplex}_number_of
  5323   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  5324   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  5325   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  5326   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  5327   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  5328   star_of_power <-- hypreal_of_real_power
  5329   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  5330 
  5331 * Hyperreal: new method "transfer" that implements the transfer
  5332 principle of nonstandard analysis. With a subgoal that mentions
  5333 nonstandard types like "'a star", the command "apply transfer"
  5334 replaces it with an equivalent one that mentions only standard types.
  5335 To be successful, all free variables must have standard types; non-
  5336 standard variables must have explicit universal quantifiers.
  5337 
  5338 * Hyperreal: A theory of Taylor series.
  5339 
  5340 
  5341 *** HOLCF ***
  5342 
  5343 * Discontinued special version of 'constdefs' (which used to support
  5344 continuous functions) in favor of the general Pure one with full
  5345 type-inference.
  5346 
  5347 * New simplification procedure for solving continuity conditions; it
  5348 is much faster on terms with many nested lambda abstractions (cubic
  5349 instead of exponential time).
  5350 
  5351 * New syntax for domain package: selector names are now optional.
  5352 Parentheses should be omitted unless argument is lazy, for example:
  5353 
  5354   domain 'a stream = cons "'a" (lazy "'a stream")
  5355 
  5356 * New command 'fixrec' for defining recursive functions with pattern
  5357 matching; defining multiple functions with mutual recursion is also
  5358 supported.  Patterns may include the constants cpair, spair, up, sinl,
  5359 sinr, or any data constructor defined by the domain package. The given
  5360 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  5361 syntax and examples.
  5362 
  5363 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  5364 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  5365 but the proof obligation additionally includes an admissibility
  5366 requirement. The packages generate instances of class cpo or pcpo,
  5367 with continuity and strictness theorems for Rep and Abs.
  5368 
  5369 * HOLCF: Many theorems have been renamed according to a more standard naming
  5370 scheme (INCOMPATIBILITY):
  5371 
  5372   foo_inject:  "foo$x = foo$y ==> x = y"
  5373   foo_eq:      "(foo$x = foo$y) = (x = y)"
  5374   foo_less:    "(foo$x << foo$y) = (x << y)"
  5375   foo_strict:  "foo$UU = UU"
  5376   foo_defined: "... ==> foo$x ~= UU"
  5377   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  5378 
  5379 
  5380 *** ZF ***
  5381 
  5382 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  5383 including the First Isomorphism Theorem (on quotienting by the kernel
  5384 of a homomorphism).
  5385 
  5386 * ZF/Simplifier: install second copy of type solver that actually
  5387 makes use of TC rules declared to Isar proof contexts (or locales);
  5388 the old version is still required for ML proof scripts.
  5389 
  5390 
  5391 *** Cube ***
  5392 
  5393 * Converted to Isar theory format; use locales instead of axiomatic
  5394 theories.
  5395 
  5396 
  5397 *** ML ***
  5398 
  5399 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  5400 for ||>, ||>>, |>>,
  5401 
  5402 * Pure/library.ML no longer defines its own option datatype, but uses
  5403 that of the SML basis, which has constructors NONE and SOME instead of
  5404 None and Some, as well as exception Option.Option instead of OPTION.
  5405 The functions the, if_none, is_some, is_none have been adapted
  5406 accordingly, while Option.map replaces apsome.
  5407 
  5408 * Pure/library.ML: the exception LIST has been given up in favour of
  5409 the standard exceptions Empty and Subscript, as well as
  5410 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  5411 superceded by the standard hd and tl functions etc.
  5412 
  5413 A number of basic list functions are no longer exported to the ML
  5414 toplevel, as they are variants of predefined functions.  The following
  5415 suggests how one can translate existing code:
  5416 
  5417     rev_append xs ys = List.revAppend (xs, ys)
  5418     nth_elem (i, xs) = List.nth (xs, i)
  5419     last_elem xs = List.last xs
  5420     flat xss = List.concat xss
  5421     seq fs = List.app fs
  5422     partition P xs = List.partition P xs
  5423     mapfilter f xs = List.mapPartial f xs
  5424 
  5425 * Pure/library.ML: several combinators for linear functional
  5426 transformations, notably reverse application and composition:
  5427 
  5428   x |> f                f #> g
  5429   (x, y) |-> f          f #-> g
  5430 
  5431 * Pure/library.ML: introduced/changed precedence of infix operators:
  5432 
  5433   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  5434   infix 2 ?;
  5435   infix 3 o oo ooo oooo;
  5436   infix 4 ~~ upto downto;
  5437 
  5438 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  5439 infix operators.
  5440 
  5441 * Pure/library.ML: natural list combinators fold, fold_rev, and
  5442 fold_map support linear functional transformations and nesting.  For
  5443 example:
  5444 
  5445   fold f [x1, ..., xN] y =
  5446     y |> f x1 |> ... |> f xN
  5447 
  5448   (fold o fold) f [xs1, ..., xsN] y =
  5449     y |> fold f xs1 |> ... |> fold f xsN
  5450 
  5451   fold f [x1, ..., xN] =
  5452     f x1 #> ... #> f xN
  5453 
  5454   (fold o fold) f [xs1, ..., xsN] =
  5455     fold f xs1 #> ... #> fold f xsN
  5456 
  5457 * Pure/library.ML: the following selectors on type 'a option are
  5458 available:
  5459 
  5460   the:               'a option -> 'a  (*partial*)
  5461   these:             'a option -> 'a  where 'a = 'b list
  5462   the_default: 'a -> 'a option -> 'a
  5463   the_list:          'a option -> 'a list
  5464 
  5465 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5466 basic operations for association lists, following natural argument
  5467 order; moreover the explicit equality predicate passed here avoids
  5468 potentially expensive polymorphic runtime equality checks.
  5469 The old functions may be expressed as follows:
  5470 
  5471   assoc = uncurry (AList.lookup (op =))
  5472   assocs = these oo AList.lookup (op =)
  5473   overwrite = uncurry (AList.update (op =)) o swap
  5474 
  5475 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5476 
  5477   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  5478   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  5479 
  5480 replacing make_keylist and keyfilter (occassionally used)
  5481 Naive rewrites:
  5482 
  5483   make_keylist = AList.make
  5484   keyfilter = AList.find (op =)
  5485 
  5486 * eq_fst and eq_snd now take explicit equality parameter, thus
  5487   avoiding eqtypes. Naive rewrites:
  5488 
  5489     eq_fst = eq_fst (op =)
  5490     eq_snd = eq_snd (op =)
  5491 
  5492 * Removed deprecated apl and apr (rarely used).
  5493   Naive rewrites:
  5494 
  5495     apl (n, op) =>>= curry op n
  5496     apr (op, m) =>>= fn n => op (n, m)
  5497 
  5498 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  5499 provides a reasonably efficient light-weight implementation of sets as
  5500 lists.
  5501 
  5502 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  5503 few new operations; existing lookup and update are now curried to
  5504 follow natural argument order (for use with fold etc.);
  5505 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  5506 
  5507 * Pure/General: output via the Isabelle channels of
  5508 writeln/warning/error etc. is now passed through Output.output, with a
  5509 hook for arbitrary transformations depending on the print_mode
  5510 (cf. Output.add_mode -- the first active mode that provides a output
  5511 function wins).  Already formatted output may be embedded into further
  5512 text via Output.raw; the result of Pretty.string_of/str_of and derived
  5513 functions (string_of_term/cterm/thm etc.) is already marked raw to
  5514 accommodate easy composition of diagnostic messages etc.  Programmers
  5515 rarely need to care about Output.output or Output.raw at all, with
  5516 some notable exceptions: Output.output is required when bypassing the
  5517 standard channels (writeln etc.), or in token translations to produce
  5518 properly formatted results; Output.raw is required when capturing
  5519 already output material that will eventually be presented to the user
  5520 a second time.  For the default print mode, both Output.output and
  5521 Output.raw have no effect.
  5522 
  5523 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  5524 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  5525 cumulative results are displayed at the end of a batch session.
  5526 
  5527 * Pure/General: File.sysify_path and File.quote_sysify path have been
  5528 replaced by File.platform_path and File.shell_path (with appropriate
  5529 hooks).  This provides a clean interface for unusual systems where the
  5530 internal and external process view of file names are different.
  5531 
  5532 * Pure: more efficient orders for basic syntactic entities: added
  5533 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  5534 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  5535 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  5536 orders now -- potential INCOMPATIBILITY for code that depends on a
  5537 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  5538 Library.sort_strings on result).
  5539 
  5540 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  5541 fold_types traverse types/terms from left to right, observing natural
  5542 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  5543 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  5544 
  5545 * Pure: name spaces have been refined, with significant changes of the
  5546 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  5547 to extern(_table).  The plain name entry path is superceded by a
  5548 general 'naming' context, which also includes the 'policy' to produce
  5549 a fully qualified name and external accesses of a fully qualified
  5550 name; NameSpace.extend is superceded by context dependent
  5551 Sign.declare_name.  Several theory and proof context operations modify
  5552 the naming context.  Especially note Theory.restore_naming and
  5553 ProofContext.restore_naming to get back to a sane state; note that
  5554 Theory.add_path is no longer sufficient to recover from
  5555 Theory.absolute_path in particular.
  5556 
  5557 * Pure: new flags short_names (default false) and unique_names
  5558 (default true) for controlling output of qualified names.  If
  5559 short_names is set, names are printed unqualified.  If unique_names is
  5560 reset, the name prefix is reduced to the minimum required to achieve
  5561 the original result when interning again, even if there is an overlap
  5562 with earlier declarations.
  5563 
  5564 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  5565 now 'extend', and 'merge' gets an additional Pretty.pp argument
  5566 (useful for printing error messages).  INCOMPATIBILITY.
  5567 
  5568 * Pure: major reorganization of the theory context.  Type Sign.sg and
  5569 Theory.theory are now identified, referring to the universal
  5570 Context.theory (see Pure/context.ML).  Actual signature and theory
  5571 content is managed as theory data.  The old code and interfaces were
  5572 spread over many files and structures; the new arrangement introduces
  5573 considerable INCOMPATIBILITY to gain more clarity:
  5574 
  5575   Context -- theory management operations (name, identity, inclusion,
  5576     parents, ancestors, merge, etc.), plus generic theory data;
  5577 
  5578   Sign -- logical signature and syntax operations (declaring consts,
  5579     types, etc.), plus certify/read for common entities;
  5580 
  5581   Theory -- logical theory operations (stating axioms, definitions,
  5582     oracles), plus a copy of logical signature operations (consts,
  5583     types, etc.); also a few basic management operations (Theory.copy,
  5584     Theory.merge, etc.)
  5585 
  5586 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  5587 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  5588 for convenience -- they merely return the theory.
  5589 
  5590 * Pure: type Type.tsig is superceded by theory in most interfaces.
  5591 
  5592 * Pure: the Isar proof context type is already defined early in Pure
  5593 as Context.proof (note that ProofContext.context and Proof.context are
  5594 aliases, where the latter is the preferred name).  This enables other
  5595 Isabelle components to refer to that type even before Isar is present.
  5596 
  5597 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  5598 typeK, constK, axiomK, oracleK), but provide explicit operations for
  5599 any of these kinds.  For example, Sign.intern typeK is now
  5600 Sign.intern_type, Theory.hide_space Sign.typeK is now
  5601 Theory.hide_types.  Also note that former
  5602 Theory.hide_classes/types/consts are now
  5603 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  5604 internalize their arguments!  INCOMPATIBILITY.
  5605 
  5606 * Pure: get_thm interface (of PureThy and ProofContext) expects
  5607 datatype thmref (with constructors Name and NameSelection) instead of
  5608 plain string -- INCOMPATIBILITY;
  5609 
  5610 * Pure: cases produced by proof methods specify options, where NONE
  5611 means to remove case bindings -- INCOMPATIBILITY in
  5612 (RAW_)METHOD_CASES.
  5613 
  5614 * Pure: the following operations retrieve axioms or theorems from a
  5615 theory node or theory hierarchy, respectively:
  5616 
  5617   Theory.axioms_of: theory -> (string * term) list
  5618   Theory.all_axioms_of: theory -> (string * term) list
  5619   PureThy.thms_of: theory -> (string * thm) list
  5620   PureThy.all_thms_of: theory -> (string * thm) list
  5621 
  5622 * Pure: print_tac now outputs the goal through the trace channel.
  5623 
  5624 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  5625 Reference Toplevel.debug (default false) controls detailed printing
  5626 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  5627 controls execution profiling -- set to 1 for time and 2 for space
  5628 (both increase the runtime).
  5629 
  5630 * Isar session: The initial use of ROOT.ML is now always timed,
  5631 i.e. the log will show the actual process times, in contrast to the
  5632 elapsed wall-clock time that the outer shell wrapper produces.
  5633 
  5634 * Simplifier: improved handling of bound variables (nameless
  5635 representation, avoid allocating new strings).  Simprocs that invoke
  5636 the Simplifier recursively should use Simplifier.inherit_bounds to
  5637 avoid local name clashes.  Failure to do so produces warnings
  5638 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  5639 for further details.
  5640 
  5641 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  5642 bindings for all theorems stored within a given theory; this may help
  5643 in porting non-Isar theories to Isar ones, while keeping ML proof
  5644 scripts for the time being.
  5645 
  5646 * ML operator HTML.with_charset specifies the charset begin used for
  5647 generated HTML files.  For example:
  5648 
  5649   HTML.with_charset "utf-8" use_thy "Hebrew";
  5650   HTML.with_charset "utf-8" use_thy "Chinese";
  5651 
  5652 
  5653 *** System ***
  5654 
  5655 * Allow symlinks to all proper Isabelle executables (Isabelle,
  5656 isabelle, isatool etc.).
  5657 
  5658 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  5659 isatool doc, isatool mkdir, display_drafts etc.).
  5660 
  5661 * isatool usedir: option -f allows specification of the ML file to be
  5662 used by Isabelle; default is ROOT.ML.
  5663 
  5664 * New isatool version outputs the version identifier of the Isabelle
  5665 distribution being used.
  5666 
  5667 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  5668 (containing Boolean satisfiability problems) into Isabelle/HOL
  5669 theories.
  5670 
  5671 
  5672 
  5673 New in Isabelle2004 (April 2004)
  5674 --------------------------------
  5675 
  5676 *** General ***
  5677 
  5678 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  5679   Replaces linorder.ML.
  5680 
  5681 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  5682   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  5683   (\<a>...\<z>), are now considered normal letters, and can therefore
  5684   be used anywhere where an ASCII letter (a...zA...Z) has until
  5685   now. COMPATIBILITY: This obviously changes the parsing of some
  5686   terms, especially where a symbol has been used as a binder, say
  5687   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  5688   as an identifier.  Fix it by inserting a space around former
  5689   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  5690   existing theory and ML files.
  5691 
  5692 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  5693 
  5694 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  5695   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  5696   a normal (but invisible) letter. For multiple letter subscripts repeat
  5697   \<^isub> like this: x\<^isub>1\<^isub>2.
  5698 
  5699 * Pure: There are now sub-/superscripts that can span more than one
  5700   character. Text between \<^bsub> and \<^esub> is set in subscript in
  5701   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  5702   superscript. The new control characters are not identifier parts.
  5703 
  5704 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5705   content of "..." to the latex file instead of \isacntrl... . The "..."
  5706   may consist of any printable characters excluding the end bracket >.
  5707 
  5708 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5709   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5710   declare constants "final", which prevents their being given a definition
  5711   later.  It is useful for constants whose behaviour is fixed axiomatically
  5712   rather than definitionally, such as the meta-logic connectives.
  5713 
  5714 * Pure: 'instance' now handles general arities with general sorts
  5715   (i.e. intersections of classes),
  5716 
  5717 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5718   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5719   It can be changed to alter the colors/layout of generated pages.
  5720 
  5721 
  5722 *** Isar ***
  5723 
  5724 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5725   cut_tac, subgoal_tac and thin_tac:
  5726   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5727     locales are no longer forced to write Isar proof scripts.
  5728     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5729     emulations.
  5730   - INCOMPATIBILITY: names of variables to be instantiated may no
  5731     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5732     This is consistent with the instantiation attribute "where".
  5733 
  5734 * Attributes "where" and "of":
  5735   - Now take type variables of instantiated theorem into account when reading
  5736     the instantiation string.  This fixes a bug that caused instantiated
  5737     theorems to have too special types in some circumstances.
  5738   - "where" permits explicit instantiations of type variables.
  5739 
  5740 * Calculation commands "moreover" and "also" no longer interfere with
  5741   current facts ("this"), admitting arbitrary combinations with "then"
  5742   and derived forms.
  5743 
  5744 * Locales:
  5745   - Goal statements involving the context element "includes" no longer
  5746     generate theorems with internal delta predicates (those ending on
  5747     "_axioms") in the premise.
  5748     Resolve particular premise with <locale>.intro to obtain old form.
  5749   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5750     specification and "includes" elements in goal statement.
  5751   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5752     [intro?] and [elim?] (respectively) by default.
  5753   - Experimental command for instantiation of locales in proof contexts:
  5754         instantiate <label>[<attrs>]: <loc>
  5755     Instantiates locale <loc> and adds all its theorems to the current context
  5756     taking into account their attributes.  Label and attrs are optional
  5757     modifiers, like in theorem declarations.  If present, names of
  5758     instantiated theorems are qualified with <label>, and the attributes
  5759     <attrs> are applied after any attributes these theorems might have already.
  5760       If the locale has assumptions, a chained fact of the form
  5761     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5762     are derived.  The command does not support old-style locales declared
  5763     with "locale (open)".
  5764       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5765 
  5766 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5767   (Isar) contexts.
  5768 
  5769 
  5770 *** HOL ***
  5771 
  5772 * Proof import: new image HOL4 contains the imported library from
  5773   the HOL4 system with about 2500 theorems. It is imported by
  5774   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5775   can be used like any other Isabelle image.  See
  5776   HOL/Import/HOL/README for more information.
  5777 
  5778 * Simplifier:
  5779   - Much improved handling of linear and partial orders.
  5780     Reasoners for linear and partial orders are set up for type classes
  5781     "linorder" and "order" respectively, and are added to the default simpset
  5782     as solvers.  This means that the simplifier can build transitivity chains
  5783     to solve goals from the assumptions.
  5784   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5785     of blast or auto after simplification become unnecessary because the goal
  5786     is solved by simplification already.
  5787 
  5788 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5789     all proved in axiomatic type classes for semirings, rings and fields.
  5790 
  5791 * Numerics:
  5792   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5793     now formalized using the Ring_and_Field theory mentioned above.
  5794   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5795     than before, because now they are set up once in a generic manner.
  5796   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5797     Look for the general versions in Ring_and_Field (and Power if they concern
  5798     exponentiation).
  5799 
  5800 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5801 
  5802 * Records:
  5803   - Record types are now by default printed with their type abbreviation
  5804     instead of the list of all field types. This can be configured via
  5805     the reference "print_record_type_abbr".
  5806   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5807     (not enabled by default).
  5808   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5809     EX x. x = sel r to True (not enabled by default).
  5810   - Tactic "record_split_simp_tac" to split and simplify records added.
  5811 
  5812 * 'specification' command added, allowing for definition by
  5813   specification.  There is also an 'ax_specification' command that
  5814   introduces the new constants axiomatically.
  5815 
  5816 * arith(_tac) is now able to generate counterexamples for reals as well.
  5817 
  5818 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5819 
  5820 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5821   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5822 
  5823 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5824   matrix theory to linear programming.
  5825 
  5826 * Unions and Intersections:
  5827   The latex output syntax of UN and INT has been changed
  5828   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5829   i.e. the index formulae has become a subscript.
  5830   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5831 
  5832 * Unions and Intersections over Intervals:
  5833   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5834   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5835   like in normal math, and corresponding versions for < and for intersection.
  5836 
  5837 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5838   lexicographic dictonary ordering has been added as "lexord".
  5839 
  5840 * ML: the legacy theory structures Int and List have been removed. They had
  5841   conflicted with ML Basis Library structures having the same names.
  5842 
  5843 * 'refute' command added to search for (finite) countermodels.  Only works
  5844   for a fragment of HOL.  The installation of an external SAT solver is
  5845   highly recommended.  See "HOL/Refute.thy" for details.
  5846 
  5847 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5848   formulae under an assignment of free variables to random values.
  5849   In contrast to 'refute', it can deal with inductive datatypes,
  5850   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5851   for examples.
  5852 
  5853 
  5854 *** HOLCF ***
  5855 
  5856 * Streams now come with concatenation and are part of the HOLCF image
  5857 
  5858 
  5859 
  5860 New in Isabelle2003 (May 2003)
  5861 ------------------------------
  5862 
  5863 *** General ***
  5864 
  5865 * Provers/simplifier:
  5866 
  5867   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5868     Assumptions are now subject to complete mutual simplification,
  5869     not just from left to right. The simplifier now preserves
  5870     the order of assumptions.
  5871 
  5872     Potential INCOMPATIBILITY:
  5873 
  5874     -- simp sometimes diverges where the old version did
  5875        not, e.g. invoking simp on the goal
  5876 
  5877         [| P (f x); y = x; f x = f y |] ==> Q
  5878 
  5879        now gives rise to the infinite reduction sequence
  5880 
  5881         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5882 
  5883        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5884        kind of problem.
  5885 
  5886     -- Tactics combining classical reasoner and simplification (such as auto)
  5887        are also affected by this change, because many of them rely on
  5888        simp. They may sometimes diverge as well or yield a different numbers
  5889        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5890        in case of problems. Sometimes subsequent calls to the classical
  5891        reasoner will fail because a preceeding call to the simplifier too
  5892        eagerly simplified the goal, e.g. deleted redundant premises.
  5893 
  5894   - The simplifier trace now shows the names of the applied rewrite rules
  5895 
  5896   - You can limit the number of recursive invocations of the simplifier
  5897     during conditional rewriting (where the simplifie tries to solve the
  5898     conditions before applying the rewrite rule):
  5899     ML "simp_depth_limit := n"
  5900     where n is an integer. Thus you can force termination where previously
  5901     the simplifier would diverge.
  5902 
  5903   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5904 
  5905   - No longer aborts on failed congruence proof.  Instead, the
  5906     congruence is ignored.
  5907 
  5908 * Pure: New generic framework for extracting programs from constructive
  5909   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5910   as HOL/Extraction for some case studies.
  5911 
  5912 * Pure: The main goal of the proof state is no longer shown by default, only
  5913 the subgoals. This behaviour is controlled by a new flag.
  5914    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5915 (ML: Proof.show_main_goal).
  5916 
  5917 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5918 rules whose conclusion matches subgoal 1:
  5919       PG menu: Isabelle/Isar -> Show me -> matching rules
  5920 The rules are ordered by how closely they match the subgoal.
  5921 In particular, rules that solve a subgoal outright are displayed first
  5922 (or rather last, the way they are printed).
  5923 (ML: ProofGeneral.print_intros())
  5924 
  5925 * Pure: New flag trace_unify_fail causes unification to print
  5926 diagnostic information (PG: in trace buffer) when it fails. This is
  5927 useful for figuring out why single step proofs like rule, erule or
  5928 assumption failed.
  5929 
  5930 * Pure: Locale specifications now produce predicate definitions
  5931 according to the body of text (covering assumptions modulo local
  5932 definitions); predicate "loc_axioms" covers newly introduced text,
  5933 while "loc" is cumulative wrt. all included locale expressions; the
  5934 latter view is presented only on export into the global theory
  5935 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5936 on the old view without predicates;
  5937 
  5938 * Pure: predefined locales "var" and "struct" are useful for sharing
  5939 parameters (as in CASL, for example); just specify something like
  5940 ``var x + var y + struct M'' as import;
  5941 
  5942 * Pure: improved thms_containing: proper indexing of facts instead of
  5943 raw theorems; check validity of results wrt. current name space;
  5944 include local facts of proof configuration (also covers active
  5945 locales), cover fixed variables in index; may use "_" in term
  5946 specification; an optional limit for the number of printed facts may
  5947 be given (the default is 40);
  5948 
  5949 * Pure: disallow duplicate fact bindings within new-style theory files
  5950 (batch-mode only);
  5951 
  5952 * Provers: improved induct method: assumptions introduced by case
  5953 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5954 the goal statement); "foo" still refers to all facts collectively;
  5955 
  5956 * Provers: the function blast.overloaded has been removed: all constants
  5957 are regarded as potentially overloaded, which improves robustness in exchange
  5958 for slight decrease in efficiency;
  5959 
  5960 * Provers/linorder: New generic prover for transitivity reasoning over
  5961 linear orders.  Note: this prover is not efficient!
  5962 
  5963 * Isar: preview of problems to finish 'show' now produce an error
  5964 rather than just a warning (in interactive mode);
  5965 
  5966 
  5967 *** HOL ***
  5968 
  5969 * arith(_tac)
  5970 
  5971  - Produces a counter example if it cannot prove a goal.
  5972    Note that the counter example may be spurious if the goal is not a formula
  5973    of quantifier-free linear arithmetic.
  5974    In ProofGeneral the counter example appears in the trace buffer.
  5975 
  5976  - Knows about div k and mod k where k is a numeral of type nat or int.
  5977 
  5978  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  5979    linear arithmetic fails. This takes account of quantifiers and divisibility.
  5980    Presburger arithmetic can also be called explicitly via presburger(_tac).
  5981 
  5982 * simp's arithmetic capabilities have been enhanced a bit: it now
  5983 takes ~= in premises into account (by performing a case split);
  5984 
  5985 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  5986 are distributed over a sum of terms;
  5987 
  5988 * New tactic "trans_tac" and method "trans" instantiate
  5989 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  5990 "<=", "<" and "=").
  5991 
  5992 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  5993 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  5994 
  5995 * 'typedef' command has new option "open" to suppress the set
  5996 definition;
  5997 
  5998 * functions Min and Max on finite sets have been introduced (theory
  5999 Finite_Set);
  6000 
  6001 * attribute [symmetric] now works for relations as well; it turns
  6002 (x,y) : R^-1 into (y,x) : R, and vice versa;
  6003 
  6004 * induct over a !!-quantified statement (say !!x1..xn):
  6005   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  6006 
  6007 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  6008 %x. None. Warning: empty_def now refers to the previously hidden definition
  6009 of the empty set.
  6010 
  6011 * Algebra: formalization of classical algebra.  Intended as base for
  6012 any algebraic development in Isabelle.  Currently covers group theory
  6013 (up to Sylow's theorem) and ring theory (Universal Property of
  6014 Univariate Polynomials).  Contributions welcome;
  6015 
  6016 * GroupTheory: deleted, since its material has been moved to Algebra;
  6017 
  6018 * Complex: new directory of the complex numbers with numeric constants,
  6019 nonstandard complex numbers, and some complex analysis, standard and
  6020 nonstandard (Jacques Fleuriot);
  6021 
  6022 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  6023 
  6024 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  6025 Fleuriot);
  6026 
  6027 * Real/HahnBanach: updated and adapted to locales;
  6028 
  6029 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  6030 Gray and Kramer);
  6031 
  6032 * UNITY: added the Meier-Sanders theory of progress sets;
  6033 
  6034 * MicroJava: bytecode verifier and lightweight bytecode verifier
  6035 as abstract algorithms, instantiated to the JVM;
  6036 
  6037 * Bali: Java source language formalization. Type system, operational
  6038 semantics, axiomatic semantics. Supported language features:
  6039 classes, interfaces, objects,virtual methods, static methods,
  6040 static/instance fields, arrays, access modifiers, definite
  6041 assignment, exceptions.
  6042 
  6043 
  6044 *** ZF ***
  6045 
  6046 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  6047 universe, etc.);
  6048 
  6049 * Main ZF: virtually all theories converted to new-style format;
  6050 
  6051 
  6052 *** ML ***
  6053 
  6054 * Pure: Tactic.prove provides sane interface for internal proofs;
  6055 omits the infamous "standard" operation, so this is more appropriate
  6056 than prove_goalw_cterm in many situations (e.g. in simprocs);
  6057 
  6058 * Pure: improved error reporting of simprocs;
  6059 
  6060 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  6061 up simprocs;
  6062 
  6063 
  6064 *** Document preparation ***
  6065 
  6066 * uses \par instead of \\ for line breaks in theory text. This may
  6067 shift some page breaks in large documents. To get the old behaviour
  6068 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  6069 
  6070 * minimized dependencies of isabelle.sty and isabellesym.sty on
  6071 other packages
  6072 
  6073 * \<euro> now needs package babel/greek instead of marvosym (which
  6074 broke \Rightarrow)
  6075 
  6076 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  6077 textcomp package)
  6078 
  6079 
  6080 
  6081 New in Isabelle2002 (March 2002)
  6082 --------------------------------
  6083 
  6084 *** Document preparation ***
  6085 
  6086 * greatly simplified document preparation setup, including more
  6087 graceful interpretation of isatool usedir -i/-d/-D options, and more
  6088 instructive isatool mkdir; users should basically be able to get
  6089 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  6090 users may run a separate document processing stage manually like this:
  6091 "isatool usedir -D output HOL Test && isatool document Test/output";
  6092 
  6093 * theory dependency graph may now be incorporated into documents;
  6094 isatool usedir -g true will produce session_graph.eps/.pdf for use
  6095 with \includegraphics of LaTeX;
  6096 
  6097 * proper spacing of consecutive markup elements, especially text
  6098 blocks after section headings;
  6099 
  6100 * support bold style (for single symbols only), input syntax is like
  6101 this: "\<^bold>\<alpha>" or "\<^bold>A";
  6102 
  6103 * \<bullet> is now output as bold \cdot by default, which looks much
  6104 better in printed text;
  6105 
  6106 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  6107 note that these symbols are currently unavailable in Proof General /
  6108 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  6109 
  6110 * isatool latex no longer depends on changed TEXINPUTS, instead
  6111 isatool document copies the Isabelle style files to the target
  6112 location;
  6113 
  6114 
  6115 *** Isar ***
  6116 
  6117 * Pure/Provers: improved proof by cases and induction;
  6118   - 'case' command admits impromptu naming of parameters (such as
  6119     "case (Suc n)");
  6120   - 'induct' method divinates rule instantiation from the inductive
  6121     claim; no longer requires excessive ?P bindings for proper
  6122     instantiation of cases;
  6123   - 'induct' method properly enumerates all possibilities of set/type
  6124     rules; as a consequence facts may be also passed through *type*
  6125     rules without further ado;
  6126   - 'induct' method now derives symbolic cases from the *rulified*
  6127     rule (before it used to rulify cases stemming from the internal
  6128     atomized version); this means that the context of a non-atomic
  6129     statement becomes is included in the hypothesis, avoiding the
  6130     slightly cumbersome show "PROP ?case" form;
  6131   - 'induct' may now use elim-style induction rules without chaining
  6132     facts, using ``missing'' premises from the goal state; this allows
  6133     rules stemming from inductive sets to be applied in unstructured
  6134     scripts, while still benefitting from proper handling of non-atomic
  6135     statements; NB: major inductive premises need to be put first, all
  6136     the rest of the goal is passed through the induction;
  6137   - 'induct' proper support for mutual induction involving non-atomic
  6138     rule statements (uses the new concept of simultaneous goals, see
  6139     below);
  6140   - append all possible rule selections, but only use the first
  6141     success (no backtracking);
  6142   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  6143   - undeclared rule case names default to numbers 1, 2, 3, ...;
  6144   - added 'print_induct_rules' (covered by help item in recent Proof
  6145     General versions);
  6146   - moved induct/cases attributes to Pure, methods to Provers;
  6147   - generic method setup instantiated for FOL and HOL;
  6148 
  6149 * Pure: support multiple simultaneous goal statements, for example
  6150 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  6151 meta-level mechanism, this acts as if several individual goals had
  6152 been stated separately; in particular common proof methods need to be
  6153 repeated in order to cover all claims; note that a single elimination
  6154 step is *not* sufficient to establish the two conjunctions, so this
  6155 fails:
  6156 
  6157   assume "A & B" then have A and B ..   (*".." fails*)
  6158 
  6159 better use "obtain" in situations as above; alternative refer to
  6160 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  6161 
  6162 * Pure: proper integration with ``locales''; unlike the original
  6163 version by Florian Kammller, Isar locales package high-level proof
  6164 contexts rather than raw logical ones (e.g. we admit to include
  6165 attributes everywhere); operations on locales include merge and
  6166 rename; support for implicit arguments (``structures''); simultaneous
  6167 type-inference over imports and text; see also HOL/ex/Locales.thy for
  6168 some examples;
  6169 
  6170 * Pure: the following commands have been ``localized'', supporting a
  6171 target locale specification "(in name)": 'lemma', 'theorem',
  6172 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  6173 stored both within the locale and at the theory level (exported and
  6174 qualified by the locale name);
  6175 
  6176 * Pure: theory goals may now be specified in ``long'' form, with
  6177 ad-hoc contexts consisting of arbitrary locale elements. for example
  6178 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  6179 definitions may be given, too); the result is a meta-level rule with
  6180 the context elements being discharged in the obvious way;
  6181 
  6182 * Pure: new proof command 'using' allows to augment currently used
  6183 facts after a goal statement ('using' is syntactically analogous to
  6184 'apply', but acts on the goal's facts only); this allows chained facts
  6185 to be separated into parts given before and after a claim, as in
  6186 ``from a and b have C using d and e <proof>'';
  6187 
  6188 * Pure: renamed "antecedent" case to "rule_context";
  6189 
  6190 * Pure: new 'judgment' command records explicit information about the
  6191 object-logic embedding (used by several tools internally); no longer
  6192 use hard-wired "Trueprop";
  6193 
  6194 * Pure: added 'corollary' command;
  6195 
  6196 * Pure: fixed 'token_translation' command;
  6197 
  6198 * Pure: removed obsolete 'exported' attribute;
  6199 
  6200 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  6201 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  6202 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  6203 
  6204 * Pure: method 'atomize' presents local goal premises as object-level
  6205 statements (atomic meta-level propositions); setup controlled via
  6206 rewrite rules declarations of 'atomize' attribute; example
  6207 application: 'induct' method with proper rule statements in improper
  6208 proof *scripts*;
  6209 
  6210 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  6211 now consider the syntactic context of assumptions, giving a better
  6212 chance to get type-inference of the arguments right (this is
  6213 especially important for locales);
  6214 
  6215 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  6216 mode;
  6217 
  6218 * Pure/obtain: the formal conclusion "thesis", being marked as
  6219 ``internal'', may no longer be reference directly in the text;
  6220 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  6221 situations;
  6222 
  6223 * Pure: generic 'sym' attribute which declares a rule both as pure
  6224 'elim?' and for the 'symmetric' operation;
  6225 
  6226 * Pure: marginal comments ``--'' may now occur just anywhere in the
  6227 text; the fixed correlation with particular command syntax has been
  6228 discontinued;
  6229 
  6230 * Pure: new method 'rules' is particularly well-suited for proof
  6231 search in intuitionistic logic; a bit slower than 'blast' or 'fast