NEWS
author wenzelm
Mon Jun 27 22:44:44 2011 +0200 (2011-06-27)
changeset 43581 c3e4d280bdeb
parent 43573 81f7dca3e542
parent 43565 486b56f2139c
child 43613 7afbaf5a406b
permissions -rw-r--r--
merged
     1 Isabelle NEWS -- history user-relevant changes
     2 ==============================================
     3 
     4 New in this Isabelle version
     5 ----------------------------
     6 
     7 *** General ***
     8 
     9 * Theory loader: source files are identified by content via SHA1
    10 digests.  Discontinued former path/modtime identification and optional
    11 ISABELLE_FILE_IDENT plugin scripts.
    12 
    13 * Parallelization of nested Isar proofs is subject to
    14 Goal.parallel_proofs_threshold (default 100).  See also isabelle
    15 usedir option -Q.
    16 
    17 * Discontinued support for Poly/ML 5.2, which was the last version
    18 without proper multithreading and TimeLimit implementation.
    19 
    20 * Discontinued old lib/scripts/polyml-platform, which has been
    21 obsolete since Isabelle2009-2.
    22 
    23 * Theory loader: source files are exclusively located via the master
    24 directory of each theory node (where the .thy file itself resides).
    25 The global load path (such as src/HOL/Library) has been discontinued.
    26 Note that the path element ~~ may be used to reference theories in the
    27 Isabelle home folder -- for instance, "~~/src/HOL/Library/FuncSet".
    28 INCOMPATIBILITY.
    29 
    30 * Various optional external tools are referenced more robustly and
    31 uniformly by explicit Isabelle settings as follows:
    32 
    33   ISABELLE_CSDP   (formerly CSDP_EXE)
    34   ISABELLE_GHC    (formerly EXEC_GHC or GHC_PATH)
    35   ISABELLE_OCAML  (formerly EXEC_OCAML)
    36   ISABELLE_SWIPL  (formerly EXEC_SWIPL)
    37   ISABELLE_YAP    (formerly EXEC_YAP)
    38 
    39 Note that automated detection from the file-system or search path has
    40 been discontinued.  INCOMPATIBILITY.
    41 
    42 * Name space: former unsynchronized references are now proper
    43 configuration options, with more conventional names:
    44 
    45   long_names   ~> names_long
    46   short_names  ~> names_short
    47   unique_names ~> names_unique
    48 
    49 Minor INCOMPATIBILITY, need to declare options in context like this:
    50 
    51   declare [[names_unique = false]]
    52 
    53 * Literal facts `prop` may contain dummy patterns, e.g. `_ = _`.  Note
    54 that the result needs to be unique, which means fact specifications
    55 may have to be refined after enriching a proof context.
    56 
    57 * Isabelle/Isar reference manual provides more formal references in
    58 syntax diagrams.
    59 
    60 
    61 *** HOL ***
    62 
    63 * Finite_Set.thy: more coherent development of fold_set locales:
    64 
    65     locale fun_left_comm ~> locale comp_fun_commute
    66     locale fun_left_comm_idem ~> locale comp_fun_idem
    67     
    68 Both use point-free characterisation; interpretation proofs may need adjustment.
    69 INCOMPATIBILITY.
    70 
    71 * Code generation:
    72   - theory Library/Code_Char_ord provides native ordering of characters
    73     in the target language.
    74     
    75 * Declare ext [intro] by default.  Rare INCOMPATIBILITY.
    76 
    77 * Nitpick:
    78   - Added "need" and "total_consts" options.
    79   - Reintroduced "show_skolems" option by popular demand.
    80   - Renamed attribute: nitpick_def ~> nitpick_unfold.
    81     INCOMPATIBILITY.
    82 
    83 * Sledgehammer:
    84   - sledgehammer available_provers ~> sledgehammer supported_provers
    85     INCOMPATIBILITY.
    86   - Added support for SNARK and ToFoF-E on SystemOnTPTP and for simply typed
    87     TPTP problems (TFF).
    88   - Added "type_sys", "sound", "max_mono_iters", and "max_new_mono_instances"
    89     options.
    90   - Removed "full_types" option and corresponding Proof General menu item.
    91     INCOMPATIBILITY.
    92 
    93 * Metis:
    94   - Removed "metisF" -- use "metis" instead. INCOMPATIBILITY.
    95   - Obsoleted "metisFT" -- use "metis (full_types)" instead. INCOMPATIBILITY.
    96 
    97 * "try":
    98   - Renamed "try_methods" and added "simp:", "intro:", "dest:", and "elim:"
    99     options. INCOMPATIBILITY.
   100   - Introduced "try" that not only runs "try_methods" but also "solve_direct",
   101     "sledgehammer", "quickcheck", and "nitpick".
   102 
   103 * Quickcheck:
   104   - Added "eval" option to evaluate terms for the found counterexample
   105     (currently only supported by the default (exhaustive) tester)
   106   - Added post-processing of terms to obtain readable counterexamples
   107     (currently only supported by the default (exhaustive) tester)
   108   - New counterexample generator quickcheck[narrowing] enables
   109     narrowing-based testing.
   110     It requires that the Glasgow Haskell compiler is installed and
   111     its location is known to Isabelle with the environment variable
   112     ISABELLE_GHC.
   113 
   114 * Function package: discontinued option "tailrec".
   115 INCOMPATIBILITY. Use partial_function instead.
   116 
   117 * HOL-Probability:
   118   - Caratheodory's extension lemma is now proved for ring_of_sets.
   119   - Infinite products of probability measures are now available.
   120   - Use extended reals instead of positive extended reals.
   121     INCOMPATIBILITY.
   122 
   123 
   124 *** Document preparation ***
   125 
   126 * Antiquotation @{rail} layouts railroad syntax diagrams, see also
   127 isar-ref manual.
   128 
   129 * Localized \isabellestyle switch can be used within blocks or groups
   130 like this:
   131 
   132   \isabellestyle{it}  %preferred default
   133   {\isabellestylett @{text "typewriter stuff"}}
   134 
   135 * New term style "isub" as ad-hoc conversion of variables x1, y23 into
   136 subscripted form x\<^isub>1, y\<^isub>2\<^isub>3.
   137 
   138 * Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
   139 (e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).
   140 
   141 
   142 *** ML ***
   143 
   144 * Antiquotations for ML and document preparation are managed as theory
   145 data, which requires explicit setup.
   146 
   147 * Isabelle_Process.is_active allows tools to check if the official
   148 process wrapper is running (Isabelle/Scala/jEdit) or the old TTY loop
   149 (better known as Proof General).
   150 
   151 * Structure Proof_Context follows standard naming scheme.  Old
   152 ProofContext is still available for some time as legacy alias.
   153 
   154 * Structure Timing provides various operations for timing; supersedes
   155 former start_timing/end_timing etc.
   156 
   157 * Path.print is the official way to show file-system paths to users
   158 (including quotes etc.).
   159 
   160 * Inner syntax: identifiers in parse trees of generic categories
   161 "logic", "aprop", "idt" etc. carry position information (disguised as
   162 type constraints).  Occasional INCOMPATIBILITY with non-compliant
   163 translations that choke on unexpected type constraints.  Positions can
   164 be stripped in ML translations via Syntax.strip_positions /
   165 Syntax.strip_positions_ast, or via the syntax constant
   166 "_strip_positions" within parse trees.  As last resort, positions can
   167 be disabled via the configuration option Syntax.positions, which is
   168 called "syntax_positions" in Isar attribute syntax.
   169 
   170 * Discontinued special status of various ML structures that contribute
   171 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
   172 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
   173 refer directly to Ast.Constant, Lexicon.is_identifier,
   174 Syntax_Trans.mk_binder_tr etc.
   175 
   176 * Typed print translation: discontinued show_sorts argument, which is
   177 already available via context of "advanced" translation.
   178 
   179 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
   180 goal states; body tactic needs to address all subgoals uniformly.
   181 
   182 * Slightly more special eq_list/eq_set, with shortcut involving
   183 pointer equality (assumes that eq relation is reflexive).
   184 
   185 * Classical tactics use proper Proof.context instead of historic types
   186 claset/clasimpset.  Old-style declarations like addIs, addEs, addDs
   187 operate directly on Proof.context.  Raw type claset retains its use as
   188 snapshot of the classical context, which can be recovered via
   189 (put_claset HOL_cs) etc.  Type clasimpset has been discontinued.
   190 INCOMPATIBILITY, classical tactics and derived proof methods require
   191 proper Proof.context.
   192 
   193 
   194 
   195 New in Isabelle2011 (January 2011)
   196 ----------------------------------
   197 
   198 *** General ***
   199 
   200 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
   201 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
   202 useful tooltips and hyperlinks produced from its static analysis.  The
   203 bundled component provides an executable Isabelle tool that can be run
   204 like this:
   205 
   206   Isabelle2011/bin/isabelle jedit
   207 
   208 * Significantly improved Isabelle/Isar implementation manual.
   209 
   210 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
   211 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
   212 while the default heap location within that directory lacks that extra
   213 suffix.  This isolates multiple Isabelle installations from each
   214 other, avoiding problems with old settings in new versions.
   215 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
   216 
   217 * Source files are always encoded as UTF-8, instead of old-fashioned
   218 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
   219 the following package declarations:
   220 
   221   \usepackage[utf8]{inputenc}
   222   \usepackage{textcomp}
   223 
   224 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
   225 a Unicode character is treated as a single symbol, not a sequence of
   226 non-ASCII bytes as before.  Since Isabelle/ML string literals may
   227 contain symbols without further backslash escapes, Unicode can now be
   228 used here as well.  Recall that Symbol.explode in ML provides a
   229 consistent view on symbols, while raw explode (or String.explode)
   230 merely give a byte-oriented representation.
   231 
   232 * Theory loader: source files are primarily located via the master
   233 directory of each theory node (where the .thy file itself resides).
   234 The global load path is still partially available as legacy feature.
   235 Minor INCOMPATIBILITY due to subtle change in file lookup: use
   236 explicit paths, relatively to the theory.
   237 
   238 * Special treatment of ML file names has been discontinued.
   239 Historically, optional extensions .ML or .sml were added on demand --
   240 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
   241 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
   242 
   243 * Various options that affect pretty printing etc. are now properly
   244 handled within the context via configuration options, instead of
   245 unsynchronized references or print modes.  There are both ML Config.T
   246 entities and Isar declaration attributes to access these.
   247 
   248   ML (Config.T)                 Isar (attribute)
   249 
   250   eta_contract                  eta_contract
   251   show_brackets                 show_brackets
   252   show_sorts                    show_sorts
   253   show_types                    show_types
   254   show_question_marks           show_question_marks
   255   show_consts                   show_consts
   256   show_abbrevs                  show_abbrevs
   257 
   258   Syntax.ast_trace              syntax_ast_trace
   259   Syntax.ast_stat               syntax_ast_stat
   260   Syntax.ambiguity_level        syntax_ambiguity_level
   261 
   262   Goal_Display.goals_limit      goals_limit
   263   Goal_Display.show_main_goal   show_main_goal
   264 
   265   Method.rule_trace             rule_trace
   266 
   267   Thy_Output.display            thy_output_display
   268   Thy_Output.quotes             thy_output_quotes
   269   Thy_Output.indent             thy_output_indent
   270   Thy_Output.source             thy_output_source
   271   Thy_Output.break              thy_output_break
   272 
   273 Note that corresponding "..._default" references in ML may only be
   274 changed globally at the ROOT session setup, but *not* within a theory.
   275 The option "show_abbrevs" supersedes the former print mode
   276 "no_abbrevs" with inverted meaning.
   277 
   278 * More systematic naming of some configuration options.
   279 INCOMPATIBILITY.
   280 
   281   trace_simp  ~>  simp_trace
   282   debug_simp  ~>  simp_debug
   283 
   284 * Support for real valued configuration options, using simplistic
   285 floating-point notation that coincides with the inner syntax for
   286 float_token.
   287 
   288 * Support for real valued preferences (with approximative PGIP type):
   289 front-ends need to accept "pgint" values in float notation.
   290 INCOMPATIBILITY.
   291 
   292 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
   293 DejaVu Sans.
   294 
   295 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   296 
   297 
   298 *** Pure ***
   299 
   300 * Command 'type_synonym' (with single argument) replaces somewhat
   301 outdated 'types', which is still available as legacy feature for some
   302 time.
   303 
   304 * Command 'nonterminal' (with 'and' separated list of arguments)
   305 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
   306 
   307 * Command 'notepad' replaces former 'example_proof' for
   308 experimentation in Isar without any result.  INCOMPATIBILITY.
   309 
   310 * Locale interpretation commands 'interpret' and 'sublocale' accept
   311 lists of equations to map definitions in a locale to appropriate
   312 entities in the context of the interpretation.  The 'interpretation'
   313 command already provided this functionality.
   314 
   315 * Diagnostic command 'print_dependencies' prints the locale instances
   316 that would be activated if the specified expression was interpreted in
   317 the current context.  Variant "print_dependencies!" assumes a context
   318 without interpretations.
   319 
   320 * Diagnostic command 'print_interps' prints interpretations in proofs
   321 in addition to interpretations in theories.
   322 
   323 * Discontinued obsolete 'global' and 'local' commands to manipulate
   324 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
   325 Sign.root_path and Sign.local_path may be applied directly where this
   326 feature is still required for historical reasons.
   327 
   328 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
   329 'definition' instead.
   330 
   331 * The "prems" fact, which refers to the accidental collection of
   332 foundational premises in the context, is now explicitly marked as
   333 legacy feature and will be discontinued soon.  Consider using "assms"
   334 of the head statement or reference facts by explicit names.
   335 
   336 * Document antiquotations @{class} and @{type} print classes and type
   337 constructors.
   338 
   339 * Document antiquotation @{file} checks file/directory entries within
   340 the local file system.
   341 
   342 
   343 *** HOL ***
   344 
   345 * Coercive subtyping: functions can be declared as coercions and type
   346 inference will add them as necessary upon input of a term.  Theory
   347 Complex_Main declares real :: nat => real and real :: int => real as
   348 coercions. A coercion function f is declared like this:
   349 
   350   declare [[coercion f]]
   351 
   352 To lift coercions through type constructors (e.g. from nat => real to
   353 nat list => real list), map functions can be declared, e.g.
   354 
   355   declare [[coercion_map map]]
   356 
   357 Currently coercion inference is activated only in theories including
   358 real numbers, i.e. descendants of Complex_Main.  This is controlled by
   359 the configuration option "coercion_enabled", e.g. it can be enabled in
   360 other theories like this:
   361 
   362   declare [[coercion_enabled]]
   363 
   364 * Command 'partial_function' provides basic support for recursive
   365 function definitions over complete partial orders.  Concrete instances
   366 are provided for i) the option type, ii) tail recursion on arbitrary
   367 types, and iii) the heap monad of Imperative_HOL.  See
   368 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
   369 for examples.
   370 
   371 * Function package: f.psimps rules are no longer implicitly declared
   372 as [simp].  INCOMPATIBILITY.
   373 
   374 * Datatype package: theorems generated for executable equality (class
   375 "eq") carry proper names and are treated as default code equations.
   376 
   377 * Inductive package: now offers command 'inductive_simps' to
   378 automatically derive instantiated and simplified equations for
   379 inductive predicates, similar to 'inductive_cases'.
   380 
   381 * Command 'enriched_type' allows to register properties of the
   382 functorial structure of types.
   383 
   384 * Improved infrastructure for term evaluation using code generator
   385 techniques, in particular static evaluation conversions.
   386 
   387 * Code generator: Scala (2.8 or higher) has been added to the target
   388 languages.
   389 
   390 * Code generator: globbing constant expressions "*" and "Theory.*"
   391 have been replaced by the more idiomatic "_" and "Theory._".
   392 INCOMPATIBILITY.
   393 
   394 * Code generator: export_code without explicit file declaration prints
   395 to standard output.  INCOMPATIBILITY.
   396 
   397 * Code generator: do not print function definitions for case
   398 combinators any longer.
   399 
   400 * Code generator: simplification with rules determined with
   401 src/Tools/Code/code_simp.ML and method "code_simp".
   402 
   403 * Code generator for records: more idiomatic representation of record
   404 types.  Warning: records are not covered by ancient SML code
   405 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
   406 rep_datatype declaration helps to succeed then:
   407 
   408   record 'a foo = ...
   409   ...
   410   rep_datatype foo_ext ...
   411 
   412 * Records: logical foundation type for records does not carry a
   413 '_type' suffix any longer (obsolete due to authentic syntax).
   414 INCOMPATIBILITY.
   415 
   416 * Quickcheck now by default uses exhaustive testing instead of random
   417 testing.  Random testing can be invoked by "quickcheck [random]",
   418 exhaustive testing by "quickcheck [exhaustive]".
   419 
   420 * Quickcheck instantiates polymorphic types with small finite
   421 datatypes by default. This enables a simple execution mechanism to
   422 handle quantifiers and function equality over the finite datatypes.
   423 
   424 * Quickcheck random generator has been renamed from "code" to
   425 "random".  INCOMPATIBILITY.
   426 
   427 * Quickcheck now has a configurable time limit which is set to 30
   428 seconds by default. This can be changed by adding [timeout = n] to the
   429 quickcheck command. The time limit for Auto Quickcheck is still set
   430 independently.
   431 
   432 * Quickcheck in locales considers interpretations of that locale for
   433 counter example search.
   434 
   435 * Sledgehammer:
   436   - Added "smt" and "remote_smt" provers based on the "smt" proof
   437     method. See the Sledgehammer manual for details ("isabelle doc
   438     sledgehammer").
   439   - Renamed commands:
   440     sledgehammer atp_info ~> sledgehammer running_provers
   441     sledgehammer atp_kill ~> sledgehammer kill_provers
   442     sledgehammer available_atps ~> sledgehammer available_provers
   443     INCOMPATIBILITY.
   444   - Renamed options:
   445     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
   446     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
   447     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
   448     (and "ms" and "min" are no longer supported)
   449     INCOMPATIBILITY.
   450 
   451 * Nitpick:
   452   - Renamed options:
   453     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
   454     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
   455     INCOMPATIBILITY.
   456   - Added support for partial quotient types.
   457   - Added local versions of the "Nitpick.register_xxx" functions.
   458   - Added "whack" option.
   459   - Allow registration of quotient types as codatatypes.
   460   - Improved "merge_type_vars" option to merge more types.
   461   - Removed unsound "fast_descrs" option.
   462   - Added custom symmetry breaking for datatypes, making it possible to reach
   463     higher cardinalities.
   464   - Prevent the expansion of too large definitions.
   465 
   466 * Proof methods "metis" and "meson" now have configuration options
   467 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
   468 to diagnose these tools. E.g.
   469 
   470     using [[metis_trace = true]]
   471 
   472 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
   473 manually as command 'solve_direct'.
   474 
   475 * The default SMT solver Z3 must be enabled explicitly (due to
   476 licensing issues) by setting the environment variable
   477 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
   478 commercial applications, the SMT solver CVC3 is provided as fall-back;
   479 changing the SMT solver is done via the configuration option
   480 "smt_solver".
   481 
   482 * Remote SMT solvers need to be referred to by the "remote_" prefix,
   483 i.e. "remote_cvc3" and "remote_z3".
   484 
   485 * Added basic SMT support for datatypes, records, and typedefs using
   486 the oracle mode (no proofs).  Direct support of pairs has been dropped
   487 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
   488 support for a similar behavior).  Minor INCOMPATIBILITY.
   489 
   490 * Changed SMT configuration options:
   491   - Renamed:
   492     z3_proofs ~> smt_oracle (with inverted meaning)
   493     z3_trace_assms ~> smt_trace_used_facts
   494     INCOMPATIBILITY.
   495   - Added:
   496     smt_verbose
   497     smt_random_seed
   498     smt_datatypes
   499     smt_infer_triggers
   500     smt_monomorph_limit
   501     cvc3_options
   502     remote_cvc3_options
   503     remote_z3_options
   504     yices_options
   505 
   506 * Boogie output files (.b2i files) need to be declared in the theory
   507 header.
   508 
   509 * Simplification procedure "list_to_set_comprehension" rewrites list
   510 comprehensions applied to List.set to set comprehensions.  Occasional
   511 INCOMPATIBILITY, may be deactivated like this:
   512 
   513   declare [[simproc del: list_to_set_comprehension]]
   514 
   515 * Removed old version of primrec package.  INCOMPATIBILITY.
   516 
   517 * Removed simplifier congruence rule of "prod_case", as has for long
   518 been the case with "split".  INCOMPATIBILITY.
   519 
   520 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
   521 
   522 * Removed [split_format ... and ... and ...] version of
   523 [split_format].  Potential INCOMPATIBILITY.
   524 
   525 * Predicate "sorted" now defined inductively, with nice induction
   526 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
   527 
   528 * Constant "contents" renamed to "the_elem", to free the generic name
   529 contents for other uses.  INCOMPATIBILITY.
   530 
   531 * Renamed class eq and constant eq (for code generation) to class
   532 equal and constant equal, plus renaming of related facts and various
   533 tuning.  INCOMPATIBILITY.
   534 
   535 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
   536 
   537 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
   538 INCOMPATIBILITY.
   539 
   540 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
   541 avoid confusion with finite sets.  INCOMPATIBILITY.
   542 
   543 * Abandoned locales equiv, congruent and congruent2 for equivalence
   544 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
   545 for congruent(2)).
   546 
   547 * Some previously unqualified names have been qualified:
   548 
   549   types
   550     bool ~> HOL.bool
   551     nat ~> Nat.nat
   552 
   553   constants
   554     Trueprop ~> HOL.Trueprop
   555     True ~> HOL.True
   556     False ~> HOL.False
   557     op & ~> HOL.conj
   558     op | ~> HOL.disj
   559     op --> ~> HOL.implies
   560     op = ~> HOL.eq
   561     Not ~> HOL.Not
   562     The ~> HOL.The
   563     All ~> HOL.All
   564     Ex ~> HOL.Ex
   565     Ex1 ~> HOL.Ex1
   566     Let ~> HOL.Let
   567     If ~> HOL.If
   568     Ball ~> Set.Ball
   569     Bex ~> Set.Bex
   570     Suc ~> Nat.Suc
   571     Pair ~> Product_Type.Pair
   572     fst ~> Product_Type.fst
   573     snd ~> Product_Type.snd
   574     curry ~> Product_Type.curry
   575     op : ~> Set.member
   576     Collect ~> Set.Collect
   577 
   578 INCOMPATIBILITY.
   579 
   580 * More canonical naming convention for some fundamental definitions:
   581 
   582     bot_bool_eq ~> bot_bool_def
   583     top_bool_eq ~> top_bool_def
   584     inf_bool_eq ~> inf_bool_def
   585     sup_bool_eq ~> sup_bool_def
   586     bot_fun_eq  ~> bot_fun_def
   587     top_fun_eq  ~> top_fun_def
   588     inf_fun_eq  ~> inf_fun_def
   589     sup_fun_eq  ~> sup_fun_def
   590 
   591 INCOMPATIBILITY.
   592 
   593 * More stylized fact names:
   594 
   595   expand_fun_eq ~> fun_eq_iff
   596   expand_set_eq ~> set_eq_iff
   597   set_ext       ~> set_eqI
   598   nat_number    ~> eval_nat_numeral
   599 
   600 INCOMPATIBILITY.
   601 
   602 * Refactoring of code-generation specific operations in theory List:
   603 
   604   constants
   605     null ~> List.null
   606 
   607   facts
   608     mem_iff ~> member_def
   609     null_empty ~> null_def
   610 
   611 INCOMPATIBILITY.  Note that these were not supposed to be used
   612 regularly unless for striking reasons; their main purpose was code
   613 generation.
   614 
   615 Various operations from the Haskell prelude are used for generating
   616 Haskell code.
   617 
   618 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
   619 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
   620 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
   621 
   622 * Abolished some non-alphabetic type names: "prod" and "sum" replace
   623 "*" and "+" respectively.  INCOMPATIBILITY.
   624 
   625 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
   626 "Sum_Type.Plus" instead.
   627 
   628 * Constant "split" has been merged with constant "prod_case"; names of
   629 ML functions, facts etc. involving split have been retained so far,
   630 though.  INCOMPATIBILITY.
   631 
   632 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
   633 instead.  INCOMPATIBILITY.
   634 
   635 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
   636 INCOMPATIBILITY.
   637 
   638 * Former theory Library/Enum is now part of the HOL-Main image.
   639 INCOMPATIBILITY: all constants of the Enum theory now have to be
   640 referred to by its qualified name.
   641 
   642   enum    ~>  Enum.enum
   643   nlists  ~>  Enum.nlists
   644   product ~>  Enum.product
   645 
   646 * Theory Library/Monad_Syntax provides do-syntax for monad types.
   647 Syntax in Library/State_Monad has been changed to avoid ambiguities.
   648 INCOMPATIBILITY.
   649 
   650 * Theory Library/SetsAndFunctions has been split into
   651 Library/Function_Algebras and Library/Set_Algebras; canonical names
   652 for instance definitions for functions; various improvements.
   653 INCOMPATIBILITY.
   654 
   655 * Theory Library/Multiset provides stable quicksort implementation of
   656 sort_key.
   657 
   658 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
   659 INCOMPATIBILITY.
   660 
   661 * Session Multivariate_Analysis: introduced a type class for euclidean
   662 space.  Most theorems are now stated in terms of euclidean spaces
   663 instead of finite cartesian products.
   664 
   665   types
   666     real ^ 'n ~>  'a::real_vector
   667               ~>  'a::euclidean_space
   668               ~>  'a::ordered_euclidean_space
   669         (depends on your needs)
   670 
   671   constants
   672      _ $ _        ~> _ $$ _
   673      \<chi> x. _  ~> \<chi>\<chi> x. _
   674      CARD('n)     ~> DIM('a)
   675 
   676 Also note that the indices are now natural numbers and not from some
   677 finite type. Finite cartesian products of euclidean spaces, products
   678 of euclidean spaces the real and complex numbers are instantiated to
   679 be euclidean_spaces.  INCOMPATIBILITY.
   680 
   681 * Session Probability: introduced pextreal as positive extended real
   682 numbers.  Use pextreal as value for measures.  Introduce the
   683 Radon-Nikodym derivative, product spaces and Fubini's theorem for
   684 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
   685 the integral in Multivariate Analysis.  INCOMPATIBILITY.
   686 
   687 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   688 INCOMPATIBILITY.
   689 
   690 * Session SPARK (with image HOL-SPARK) provides commands to load and
   691 prove verification conditions generated by the SPARK Ada program
   692 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
   693 
   694 
   695 *** HOL-Algebra ***
   696 
   697 * Theorems for additive ring operations (locale abelian_monoid and
   698 descendants) are generated by interpretation from their multiplicative
   699 counterparts.  Names (in particular theorem names) have the mandatory
   700 qualifier 'add'.  Previous theorem names are redeclared for
   701 compatibility.
   702 
   703 * Structure "int_ring" is now an abbreviation (previously a
   704 definition).  This fits more natural with advanced interpretations.
   705 
   706 
   707 *** HOLCF ***
   708 
   709 * The domain package now runs in definitional mode by default: The
   710 former command 'new_domain' is now called 'domain'.  To use the domain
   711 package in its original axiomatic mode, use 'domain (unsafe)'.
   712 INCOMPATIBILITY.
   713 
   714 * The new class "domain" is now the default sort.  Class "predomain"
   715 is an unpointed version of "domain". Theories can be updated by
   716 replacing sort annotations as shown below.  INCOMPATIBILITY.
   717 
   718   'a::type ~> 'a::countable
   719   'a::cpo  ~> 'a::predomain
   720   'a::pcpo ~> 'a::domain
   721 
   722 * The old type class "rep" has been superseded by class "domain".
   723 Accordingly, users of the definitional package must remove any
   724 "default_sort rep" declarations.  INCOMPATIBILITY.
   725 
   726 * The domain package (definitional mode) now supports unpointed
   727 predomain argument types, as long as they are marked 'lazy'. (Strict
   728 arguments must be in class "domain".) For example, the following
   729 domain definition now works:
   730 
   731   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
   732 
   733 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
   734 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
   735 'a option, and 'a list.  Additionally, it configures fixrec and the
   736 domain package to work with these types.  For example:
   737 
   738   fixrec isInl :: "('a + 'b) u -> tr"
   739     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
   740 
   741   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
   742 
   743 * The "(permissive)" option of fixrec has been replaced with a
   744 per-equation "(unchecked)" option. See
   745 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
   746 
   747 * The "bifinite" class no longer fixes a constant "approx"; the class
   748 now just asserts that such a function exists.  INCOMPATIBILITY.
   749 
   750 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
   751 defines an embedding of type 'a defl into udom by default; instances
   752 of "bifinite" and "domain" classes are available in
   753 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
   754 
   755 * The syntax "REP('a)" has been replaced with "DEFL('a)".
   756 
   757 * The predicate "directed" has been removed.  INCOMPATIBILITY.
   758 
   759 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
   760 
   761 * The function "cprod_map" has been renamed to "prod_map".
   762 INCOMPATIBILITY.
   763 
   764 * The monadic bind operator on each powerdomain has new binder syntax
   765 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
   766 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
   767 
   768 * The infix syntax for binary union on each powerdomain has changed
   769 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
   770 syntax.  INCOMPATIBILITY.
   771 
   772 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
   773 still supported as an input translation.
   774 
   775 * Renamed some theorems (the original names are also still available).
   776 
   777   expand_fun_below   ~> fun_below_iff
   778   below_fun_ext      ~> fun_belowI
   779   expand_cfun_eq     ~> cfun_eq_iff
   780   ext_cfun           ~> cfun_eqI
   781   expand_cfun_below  ~> cfun_below_iff
   782   below_cfun_ext     ~> cfun_belowI
   783   cont2cont_Rep_CFun ~> cont2cont_APP
   784 
   785 * The Abs and Rep functions for various types have changed names.
   786 Related theorem names have also changed to match. INCOMPATIBILITY.
   787 
   788   Rep_CFun  ~> Rep_cfun
   789   Abs_CFun  ~> Abs_cfun
   790   Rep_Sprod ~> Rep_sprod
   791   Abs_Sprod ~> Abs_sprod
   792   Rep_Ssum  ~> Rep_ssum
   793   Abs_Ssum  ~> Abs_ssum
   794 
   795 * Lemmas with names of the form *_defined_iff or *_strict_iff have
   796 been renamed to *_bottom_iff.  INCOMPATIBILITY.
   797 
   798 * Various changes to bisimulation/coinduction with domain package:
   799 
   800   - Definitions of "bisim" constants no longer mention definedness.
   801   - With mutual recursion, "bisim" predicate is now curried.
   802   - With mutual recursion, each type gets a separate coind theorem.
   803   - Variable names in bisim_def and coinduct rules have changed.
   804 
   805 INCOMPATIBILITY.
   806 
   807 * Case combinators generated by the domain package for type "foo" are
   808 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
   809 
   810 * Several theorems have been renamed to more accurately reflect the
   811 names of constants and types involved.  INCOMPATIBILITY.
   812 
   813   thelub_const    ~> lub_const
   814   lub_const       ~> is_lub_const
   815   thelubI         ~> lub_eqI
   816   is_lub_lub      ~> is_lubD2
   817   lubI            ~> is_lub_lub
   818   unique_lub      ~> is_lub_unique
   819   is_ub_lub       ~> is_lub_rangeD1
   820   lub_bin_chain   ~> is_lub_bin_chain
   821   lub_fun         ~> is_lub_fun
   822   thelub_fun      ~> lub_fun
   823   thelub_cfun     ~> lub_cfun
   824   thelub_Pair     ~> lub_Pair
   825   lub_cprod       ~> is_lub_prod
   826   thelub_cprod    ~> lub_prod
   827   minimal_cprod   ~> minimal_prod
   828   inst_cprod_pcpo ~> inst_prod_pcpo
   829   UU_I            ~> bottomI
   830   compact_UU      ~> compact_bottom
   831   deflation_UU    ~> deflation_bottom
   832   finite_deflation_UU ~> finite_deflation_bottom
   833 
   834 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
   835 
   836   sq_ord_less_eq_trans ~> below_eq_trans
   837   sq_ord_eq_less_trans ~> eq_below_trans
   838   refl_less            ~> below_refl
   839   trans_less           ~> below_trans
   840   antisym_less         ~> below_antisym
   841   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
   842   box_less             ~> box_below
   843   rev_trans_less       ~> rev_below_trans
   844   not_less2not_eq      ~> not_below2not_eq
   845   less_UU_iff          ~> below_UU_iff
   846   flat_less_iff        ~> flat_below_iff
   847   adm_less             ~> adm_below
   848   adm_not_less         ~> adm_not_below
   849   adm_compact_not_less ~> adm_compact_not_below
   850   less_fun_def         ~> below_fun_def
   851   expand_fun_less      ~> fun_below_iff
   852   less_fun_ext         ~> fun_belowI
   853   less_discr_def       ~> below_discr_def
   854   discr_less_eq        ~> discr_below_eq
   855   less_unit_def        ~> below_unit_def
   856   less_cprod_def       ~> below_prod_def
   857   prod_lessI           ~> prod_belowI
   858   Pair_less_iff        ~> Pair_below_iff
   859   fst_less_iff         ~> fst_below_iff
   860   snd_less_iff         ~> snd_below_iff
   861   expand_cfun_less     ~> cfun_below_iff
   862   less_cfun_ext        ~> cfun_belowI
   863   injection_less       ~> injection_below
   864   less_up_def          ~> below_up_def
   865   not_Iup_less         ~> not_Iup_below
   866   Iup_less             ~> Iup_below
   867   up_less              ~> up_below
   868   Def_inject_less_eq   ~> Def_below_Def
   869   Def_less_is_eq       ~> Def_below_iff
   870   spair_less_iff       ~> spair_below_iff
   871   less_sprod           ~> below_sprod
   872   spair_less           ~> spair_below
   873   sfst_less_iff        ~> sfst_below_iff
   874   ssnd_less_iff        ~> ssnd_below_iff
   875   fix_least_less       ~> fix_least_below
   876   dist_less_one        ~> dist_below_one
   877   less_ONE             ~> below_ONE
   878   ONE_less_iff         ~> ONE_below_iff
   879   less_sinlD           ~> below_sinlD
   880   less_sinrD           ~> below_sinrD
   881 
   882 
   883 *** FOL and ZF ***
   884 
   885 * All constant names are now qualified internally and use proper
   886 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
   887 
   888 
   889 *** ML ***
   890 
   891 * Antiquotation @{assert} inlines a function bool -> unit that raises
   892 Fail if the argument is false.  Due to inlining the source position of
   893 failed assertions is included in the error output.
   894 
   895 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
   896 text is in practice always evaluated with a stable theory checkpoint.
   897 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
   898 
   899 * Antiquotation @{theory A} refers to theory A from the ancestry of
   900 the current context, not any accidental theory loader state as before.
   901 Potential INCOMPATIBILITY, subtle change in semantics.
   902 
   903 * Syntax.pretty_priority (default 0) configures the required priority
   904 of pretty-printed output and thus affects insertion of parentheses.
   905 
   906 * Syntax.default_root (default "any") configures the inner syntax
   907 category (nonterminal symbol) for parsing of terms.
   908 
   909 * Former exception Library.UnequalLengths now coincides with
   910 ListPair.UnequalLengths.
   911 
   912 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
   913 main functionality is provided by structure Simplifier.
   914 
   915 * Renamed raw "explode" function to "raw_explode" to emphasize its
   916 meaning.  Note that internally to Isabelle, Symbol.explode is used in
   917 almost all situations.
   918 
   919 * Discontinued obsolete function sys_error and exception SYS_ERROR.
   920 See implementation manual for further details on exceptions in
   921 Isabelle/ML.
   922 
   923 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
   924 meaning.
   925 
   926 * Renamed structure PureThy to Pure_Thy and moved most of its
   927 operations to structure Global_Theory, to emphasize that this is
   928 rarely-used global-only stuff.
   929 
   930 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
   931 instead (or tracing for high-volume output).
   932 
   933 * Configuration option show_question_marks only affects regular pretty
   934 printing of types and terms, not raw Term.string_of_vname.
   935 
   936 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
   937 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
   938 @{thms} for most purposes.
   939 
   940 * ML structure Unsynchronized is never opened, not even in Isar
   941 interaction mode as before.  Old Unsynchronized.set etc. have been
   942 discontinued -- use plain := instead.  This should be *rare* anyway,
   943 since modern tools always work via official context data, notably
   944 configuration options.
   945 
   946 * Parallel and asynchronous execution requires special care concerning
   947 interrupts.  Structure Exn provides some convenience functions that
   948 avoid working directly with raw Interrupt.  User code must not absorb
   949 interrupts -- intermediate handling (for cleanup etc.) needs to be
   950 followed by re-raising of the original exception.  Another common
   951 source of mistakes are "handle _" patterns, which make the meaning of
   952 the program subject to physical effects of the environment.
   953 
   954 
   955 
   956 New in Isabelle2009-2 (June 2010)
   957 ---------------------------------
   958 
   959 *** General ***
   960 
   961 * Authentic syntax for *all* logical entities (type classes, type
   962 constructors, term constants): provides simple and robust
   963 correspondence between formal entities and concrete syntax.  Within
   964 the parse tree / AST representations, "constants" are decorated by
   965 their category (class, type, const) and spelled out explicitly with
   966 their full internal name.
   967 
   968 Substantial INCOMPATIBILITY concerning low-level syntax declarations
   969 and translations (translation rules and translation functions in ML).
   970 Some hints on upgrading:
   971 
   972   - Many existing uses of 'syntax' and 'translations' can be replaced
   973     by more modern 'type_notation', 'notation' and 'abbreviation',
   974     which are independent of this issue.
   975 
   976   - 'translations' require markup within the AST; the term syntax
   977     provides the following special forms:
   978 
   979       CONST c   -- produces syntax version of constant c from context
   980       XCONST c  -- literally c, checked as constant from context
   981       c         -- literally c, if declared by 'syntax'
   982 
   983     Plain identifiers are treated as AST variables -- occasionally the
   984     system indicates accidental variables via the error "rhs contains
   985     extra variables".
   986 
   987     Type classes and type constructors are marked according to their
   988     concrete syntax.  Some old translations rules need to be written
   989     for the "type" category, using type constructor application
   990     instead of pseudo-term application of the default category
   991     "logic".
   992 
   993   - 'parse_translation' etc. in ML may use the following
   994     antiquotations:
   995 
   996       @{class_syntax c}   -- type class c within parse tree / AST
   997       @{term_syntax c}    -- type constructor c within parse tree / AST
   998       @{const_syntax c}   -- ML version of "CONST c" above
   999       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
  1000 
  1001   - Literal types within 'typed_print_translations', i.e. those *not*
  1002     represented as pseudo-terms are represented verbatim.  Use @{class
  1003     c} or @{type_name c} here instead of the above syntax
  1004     antiquotations.
  1005 
  1006 Note that old non-authentic syntax was based on unqualified base
  1007 names, so all of the above "constant" names would coincide.  Recall
  1008 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
  1009 diagnose syntax problems.
  1010 
  1011 * Type constructors admit general mixfix syntax, not just infix.
  1012 
  1013 * Concrete syntax may be attached to local entities without a proof
  1014 body, too.  This works via regular mixfix annotations for 'fix',
  1015 'def', 'obtain' etc. or via the explicit 'write' command, which is
  1016 similar to the 'notation' command in theory specifications.
  1017 
  1018 * Discontinued unnamed infix syntax (legacy feature for many years) --
  1019 need to specify constant name and syntax separately.  Internal ML
  1020 datatype constructors have been renamed from InfixName to Infix etc.
  1021 Minor INCOMPATIBILITY.
  1022 
  1023 * Schematic theorem statements need to be explicitly markup as such,
  1024 via commands 'schematic_lemma', 'schematic_theorem',
  1025 'schematic_corollary'.  Thus the relevance of the proof is made
  1026 syntactically clear, which impacts performance in a parallel or
  1027 asynchronous interactive environment.  Minor INCOMPATIBILITY.
  1028 
  1029 * Use of cumulative prems via "!" in some proof methods has been
  1030 discontinued (old legacy feature).
  1031 
  1032 * References 'trace_simp' and 'debug_simp' have been replaced by
  1033 configuration options stored in the context. Enabling tracing (the
  1034 case of debugging is similar) in proofs works via
  1035 
  1036   using [[trace_simp = true]]
  1037 
  1038 Tracing is then active for all invocations of the simplifier in
  1039 subsequent goal refinement steps. Tracing may also still be enabled or
  1040 disabled via the ProofGeneral settings menu.
  1041 
  1042 * Separate commands 'hide_class', 'hide_type', 'hide_const',
  1043 'hide_fact' replace the former 'hide' KIND command.  Minor
  1044 INCOMPATIBILITY.
  1045 
  1046 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
  1047 more efficient than combinations with -q1 or -q2.
  1048 
  1049 
  1050 *** Pure ***
  1051 
  1052 * Proofterms record type-class reasoning explicitly, using the
  1053 "unconstrain" operation internally.  This eliminates all sort
  1054 constraints from a theorem and proof, introducing explicit
  1055 OFCLASS-premises.  On the proof term level, this operation is
  1056 automatically applied at theorem boundaries, such that closed proofs
  1057 are always free of sort constraints.  INCOMPATIBILITY for tools that
  1058 inspect proof terms.
  1059 
  1060 * Local theory specifications may depend on extra type variables that
  1061 are not present in the result type -- arguments TYPE('a) :: 'a itself
  1062 are added internally.  For example:
  1063 
  1064   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
  1065 
  1066 * Predicates of locales introduced by classes carry a mandatory
  1067 "class" prefix.  INCOMPATIBILITY.
  1068 
  1069 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
  1070 
  1071 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
  1072 'class' instead.
  1073 
  1074 * Command 'code_reflect' allows to incorporate generated ML code into
  1075 runtime environment; replaces immature code_datatype antiquotation.
  1076 INCOMPATIBILITY.
  1077 
  1078 * Code generator: simple concept for abstract datatypes obeying
  1079 invariants.
  1080 
  1081 * Code generator: details of internal data cache have no impact on the
  1082 user space functionality any longer.
  1083 
  1084 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  1085 subgoals.  This is more appropriate for interpretations with 'where'.
  1086 INCOMPATIBILITY.
  1087 
  1088 * Command 'example_proof' opens an empty proof body.  This allows to
  1089 experiment with Isar, without producing any persistent result.
  1090 
  1091 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  1092 within a local theory context, with explicit checking of the
  1093 constructors involved (in contrast to the raw 'syntax' versions).
  1094 
  1095 * Commands 'types' and 'typedecl' now work within a local theory
  1096 context -- without introducing dependencies on parameters or
  1097 assumptions, which is not possible in Isabelle/Pure.
  1098 
  1099 * Command 'defaultsort' has been renamed to 'default_sort', it works
  1100 within a local theory context.  Minor INCOMPATIBILITY.
  1101 
  1102 
  1103 *** HOL ***
  1104 
  1105 * Command 'typedef' now works within a local theory context -- without
  1106 introducing dependencies on parameters or assumptions, which is not
  1107 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  1108 contain multiple interpretations of local typedefs (with different
  1109 non-emptiness proofs), even in a global theory context.
  1110 
  1111 * New package for quotient types.  Commands 'quotient_type' and
  1112 'quotient_definition' may be used for defining types and constants by
  1113 quotient constructions.  An example is the type of integers created by
  1114 quotienting pairs of natural numbers:
  1115 
  1116   fun
  1117     intrel :: "(nat * nat) => (nat * nat) => bool"
  1118   where
  1119     "intrel (x, y) (u, v) = (x + v = u + y)"
  1120 
  1121   quotient_type int = "nat * nat" / intrel
  1122     by (auto simp add: equivp_def expand_fun_eq)
  1123 
  1124   quotient_definition
  1125     "0::int" is "(0::nat, 0::nat)"
  1126 
  1127 The method "lifting" can be used to lift of theorems from the
  1128 underlying "raw" type to the quotient type.  The example
  1129 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  1130 construction and provides a reasoning infrastructure for finite sets.
  1131 
  1132 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  1133 clash with new theory Quotient in Main HOL.
  1134 
  1135 * Moved the SMT binding into the main HOL session, eliminating
  1136 separate HOL-SMT session.
  1137 
  1138 * List membership infix mem operation is only an input abbreviation.
  1139 INCOMPATIBILITY.
  1140 
  1141 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  1142 for future developements; former Library/Word.thy is still present in
  1143 the AFP entry RSAPPS.
  1144 
  1145 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  1146 longer shadowed.  INCOMPATIBILITY.
  1147 
  1148 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  1149 INCOMPATIBILITY.
  1150 
  1151 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  1152 INCOMPATIBILITY.
  1153 
  1154 * Dropped normalizing_semiring etc; use the facts in semiring classes
  1155 instead.  INCOMPATIBILITY.
  1156 
  1157 * Dropped several real-specific versions of lemmas about floor and
  1158 ceiling; use the generic lemmas from theory "Archimedean_Field"
  1159 instead.  INCOMPATIBILITY.
  1160 
  1161   floor_number_of_eq         ~> floor_number_of
  1162   le_floor_eq_number_of      ~> number_of_le_floor
  1163   le_floor_eq_zero           ~> zero_le_floor
  1164   le_floor_eq_one            ~> one_le_floor
  1165   floor_less_eq_number_of    ~> floor_less_number_of
  1166   floor_less_eq_zero         ~> floor_less_zero
  1167   floor_less_eq_one          ~> floor_less_one
  1168   less_floor_eq_number_of    ~> number_of_less_floor
  1169   less_floor_eq_zero         ~> zero_less_floor
  1170   less_floor_eq_one          ~> one_less_floor
  1171   floor_le_eq_number_of      ~> floor_le_number_of
  1172   floor_le_eq_zero           ~> floor_le_zero
  1173   floor_le_eq_one            ~> floor_le_one
  1174   floor_subtract_number_of   ~> floor_diff_number_of
  1175   floor_subtract_one         ~> floor_diff_one
  1176   ceiling_number_of_eq       ~> ceiling_number_of
  1177   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  1178   ceiling_le_zero_eq         ~> ceiling_le_zero
  1179   ceiling_le_eq_one          ~> ceiling_le_one
  1180   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  1181   less_ceiling_eq_zero       ~> zero_less_ceiling
  1182   less_ceiling_eq_one        ~> one_less_ceiling
  1183   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  1184   ceiling_less_eq_zero       ~> ceiling_less_zero
  1185   ceiling_less_eq_one        ~> ceiling_less_one
  1186   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  1187   le_ceiling_eq_zero         ~> zero_le_ceiling
  1188   le_ceiling_eq_one          ~> one_le_ceiling
  1189   ceiling_subtract_number_of ~> ceiling_diff_number_of
  1190   ceiling_subtract_one       ~> ceiling_diff_one
  1191 
  1192 * Theory "Finite_Set": various folding_XXX locales facilitate the
  1193 application of the various fold combinators on finite sets.
  1194 
  1195 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  1196 provides abstract red-black tree type which is backed by "RBT_Impl" as
  1197 implementation.  INCOMPATIBILTY.
  1198 
  1199 * Theory Library/Coinductive_List has been removed -- superseded by
  1200 AFP/thys/Coinductive.
  1201 
  1202 * Theory PReal, including the type "preal" and related operations, has
  1203 been removed.  INCOMPATIBILITY.
  1204 
  1205 * Real: new development using Cauchy Sequences.
  1206 
  1207 * Split off theory "Big_Operators" containing setsum, setprod,
  1208 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  1209 
  1210 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  1211 "Int" etc.  INCOMPATIBILITY.
  1212 
  1213 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  1214 
  1215 * New set of rules "ac_simps" provides combined assoc / commute
  1216 rewrites for all interpretations of the appropriate generic locales.
  1217 
  1218 * Renamed theory "OrderedGroup" to "Groups" and split theory
  1219 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  1220 appropriate and more consistent names suitable for name prefixes
  1221 within the HOL theories.  INCOMPATIBILITY.
  1222 
  1223 * Some generic constants have been put to appropriate theories:
  1224   - less_eq, less: Orderings
  1225   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  1226   - inverse, divide: Rings
  1227 INCOMPATIBILITY.
  1228 
  1229 * More consistent naming of type classes involving orderings (and
  1230 lattices):
  1231 
  1232     lower_semilattice                   ~> semilattice_inf
  1233     upper_semilattice                   ~> semilattice_sup
  1234 
  1235     dense_linear_order                  ~> dense_linorder
  1236 
  1237     pordered_ab_group_add               ~> ordered_ab_group_add
  1238     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  1239     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  1240     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  1241     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  1242     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  1243     pordered_cancel_semiring            ~> ordered_cancel_semiring
  1244     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  1245     pordered_comm_ring                  ~> ordered_comm_ring
  1246     pordered_comm_semiring              ~> ordered_comm_semiring
  1247     pordered_ring                       ~> ordered_ring
  1248     pordered_ring_abs                   ~> ordered_ring_abs
  1249     pordered_semiring                   ~> ordered_semiring
  1250 
  1251     ordered_ab_group_add                ~> linordered_ab_group_add
  1252     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  1253     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  1254     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  1255     ordered_field                       ~> linordered_field
  1256     ordered_field_no_lb                 ~> linordered_field_no_lb
  1257     ordered_field_no_ub                 ~> linordered_field_no_ub
  1258     ordered_field_dense_linear_order    ~> dense_linordered_field
  1259     ordered_idom                        ~> linordered_idom
  1260     ordered_ring                        ~> linordered_ring
  1261     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  1262     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  1263     ordered_ring_strict                 ~> linordered_ring_strict
  1264     ordered_semidom                     ~> linordered_semidom
  1265     ordered_semiring                    ~> linordered_semiring
  1266     ordered_semiring_1                  ~> linordered_semiring_1
  1267     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  1268     ordered_semiring_strict             ~> linordered_semiring_strict
  1269 
  1270   The following slightly odd type classes have been moved to a
  1271   separate theory Library/Lattice_Algebras:
  1272 
  1273     lordered_ab_group_add               ~> lattice_ab_group_add
  1274     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  1275     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  1276     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  1277     lordered_ring                       ~> lattice_ring
  1278 
  1279 INCOMPATIBILITY.
  1280 
  1281 * Refined field classes:
  1282   - classes division_ring_inverse_zero, field_inverse_zero,
  1283     linordered_field_inverse_zero include rule inverse 0 = 0 --
  1284     subsumes former division_by_zero class;
  1285   - numerous lemmas have been ported from field to division_ring.
  1286 INCOMPATIBILITY.
  1287 
  1288 * Refined algebra theorem collections:
  1289   - dropped theorem group group_simps, use algebra_simps instead;
  1290   - dropped theorem group ring_simps, use field_simps instead;
  1291   - proper theorem collection field_simps subsumes former theorem
  1292     groups field_eq_simps and field_simps;
  1293   - dropped lemma eq_minus_self_iff which is a duplicate for
  1294     equal_neg_zero.
  1295 INCOMPATIBILITY.
  1296 
  1297 * Theory Finite_Set and List: some lemmas have been generalized from
  1298 sets to lattices:
  1299 
  1300   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  1301   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  1302   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  1303   union_Union_fold_union        ~> sup_Sup_fold_sup
  1304   Inter_fold_inter              ~> Inf_fold_inf
  1305   Union_fold_union              ~> Sup_fold_sup
  1306   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  1307   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  1308   INTER_fold_inter              ~> INFI_fold_inf
  1309   UNION_fold_union              ~> SUPR_fold_sup
  1310 
  1311 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  1312 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  1313 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  1314 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  1315 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  1316 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  1317 
  1318 * Reorganized theory Multiset: swapped notation of pointwise and
  1319 multiset order:
  1320 
  1321   - pointwise ordering is instance of class order with standard syntax
  1322     <= and <;
  1323   - multiset ordering has syntax <=# and <#; partial order properties
  1324     are provided by means of interpretation with prefix
  1325     multiset_order;
  1326   - less duplication, less historical organization of sections,
  1327     conversion from associations lists to multisets, rudimentary code
  1328     generation;
  1329   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  1330     if needed.
  1331 
  1332 Renamed:
  1333 
  1334   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  1335   multi_count_ext  ~>  multiset_ext
  1336   diff_union_inverse2  ~>  diff_union_cancelR
  1337 
  1338 INCOMPATIBILITY.
  1339 
  1340 * Theory Permutation: replaced local "remove" by List.remove1.
  1341 
  1342 * Code generation: ML and OCaml code is decorated with signatures.
  1343 
  1344 * Theory List: added transpose.
  1345 
  1346 * Library/Nat_Bijection.thy is a collection of bijective functions
  1347 between nat and other types, which supersedes the older libraries
  1348 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  1349 
  1350   Constants:
  1351   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  1352   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  1353   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  1354   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  1355   Countable.pair_encode           ~> prod_encode
  1356   NatIso.prod2nat                 ~> prod_encode
  1357   NatIso.nat2prod                 ~> prod_decode
  1358   NatIso.sum2nat                  ~> sum_encode
  1359   NatIso.nat2sum                  ~> sum_decode
  1360   NatIso.list2nat                 ~> list_encode
  1361   NatIso.nat2list                 ~> list_decode
  1362   NatIso.set2nat                  ~> set_encode
  1363   NatIso.nat2set                  ~> set_decode
  1364 
  1365   Lemmas:
  1366   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  1367   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  1368   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  1369   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  1370   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  1371   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  1372   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  1373   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  1374   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  1375   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  1376   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  1377   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  1378   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  1379 
  1380 * Sledgehammer:
  1381   - Renamed ATP commands:
  1382     atp_info     ~> sledgehammer running_atps
  1383     atp_kill     ~> sledgehammer kill_atps
  1384     atp_messages ~> sledgehammer messages
  1385     atp_minimize ~> sledgehammer minimize
  1386     print_atps   ~> sledgehammer available_atps
  1387     INCOMPATIBILITY.
  1388   - Added user's manual ("isabelle doc sledgehammer").
  1389   - Added option syntax and "sledgehammer_params" to customize
  1390     Sledgehammer's behavior.  See the manual for details.
  1391   - Modified the Isar proof reconstruction code so that it produces
  1392     direct proofs rather than proofs by contradiction.  (This feature
  1393     is still experimental.)
  1394   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  1395     full-typed mode.
  1396   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  1397 
  1398 * Nitpick:
  1399   - Added and implemented "binary_ints" and "bits" options.
  1400   - Added "std" option and implemented support for nonstandard models.
  1401   - Added and implemented "finitize" option to improve the precision
  1402     of infinite datatypes based on a monotonicity analysis.
  1403   - Added support for quotient types.
  1404   - Added support for "specification" and "ax_specification"
  1405     constructs.
  1406   - Added support for local definitions (for "function" and
  1407     "termination" proofs).
  1408   - Added support for term postprocessors.
  1409   - Optimized "Multiset.multiset" and "FinFun.finfun".
  1410   - Improved efficiency of "destroy_constrs" optimization.
  1411   - Fixed soundness bugs related to "destroy_constrs" optimization and
  1412     record getters.
  1413   - Fixed soundness bug related to higher-order constructors.
  1414   - Fixed soundness bug when "full_descrs" is enabled.
  1415   - Improved precision of set constructs.
  1416   - Added "atoms" option.
  1417   - Added cache to speed up repeated Kodkod invocations on the same
  1418     problems.
  1419   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  1420     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  1421     "SAT4J_Light".  INCOMPATIBILITY.
  1422   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  1423     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  1424   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  1425 
  1426 * Method "induct" now takes instantiations of the form t, where t is not
  1427   a variable, as a shorthand for "x == t", where x is a fresh variable.
  1428   If this is not intended, t has to be enclosed in parentheses.
  1429   By default, the equalities generated by definitional instantiations
  1430   are pre-simplified, which may cause parameters of inductive cases
  1431   to disappear, or may even delete some of the inductive cases.
  1432   Use "induct (no_simp)" instead of "induct" to restore the old
  1433   behaviour. The (no_simp) option is also understood by the "cases"
  1434   and "nominal_induct" methods, which now perform pre-simplification, too.
  1435   INCOMPATIBILITY.
  1436 
  1437 
  1438 *** HOLCF ***
  1439 
  1440 * Variable names in lemmas generated by the domain package have
  1441 changed; the naming scheme is now consistent with the HOL datatype
  1442 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  1443 
  1444 * The domain package no longer defines the function "foo_copy" for
  1445 recursive domain "foo".  The reach lemma is now stated directly in
  1446 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  1447 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  1448 
  1449 * Most definedness lemmas generated by the domain package (previously
  1450 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  1451 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  1452 Proofs that used definedness lemmas as intro rules may break,
  1453 potential INCOMPATIBILITY.
  1454 
  1455 * Induction and casedist rules generated by the domain package now
  1456 declare proper case_names (one called "bottom", and one named for each
  1457 constructor).  INCOMPATIBILITY.
  1458 
  1459 * For mutually-recursive domains, separate "reach" and "take_lemma"
  1460 rules are generated for each domain, INCOMPATIBILITY.
  1461 
  1462   foo_bar.reach       ~> foo.reach  bar.reach
  1463   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  1464 
  1465 * Some lemmas generated by the domain package have been renamed for
  1466 consistency with the datatype package, INCOMPATIBILITY.
  1467 
  1468   foo.ind        ~> foo.induct
  1469   foo.finite_ind ~> foo.finite_induct
  1470   foo.coind      ~> foo.coinduct
  1471   foo.casedist   ~> foo.exhaust
  1472   foo.exhaust    ~> foo.nchotomy
  1473 
  1474 * For consistency with other definition packages, the fixrec package
  1475 now generates qualified theorem names, INCOMPATIBILITY.
  1476 
  1477   foo_simps  ~> foo.simps
  1478   foo_unfold ~> foo.unfold
  1479   foo_induct ~> foo.induct
  1480 
  1481 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  1482 method and internal fixrec proofs now use the default simpset instead.
  1483 INCOMPATIBILITY.
  1484 
  1485 * The "contlub" predicate has been removed.  Proof scripts should use
  1486 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  1487 
  1488 * The "admw" predicate has been removed, INCOMPATIBILITY.
  1489 
  1490 * The constants cpair, cfst, and csnd have been removed in favor of
  1491 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  1492 
  1493 
  1494 *** ML ***
  1495 
  1496 * Antiquotations for basic formal entities:
  1497 
  1498     @{class NAME}         -- type class
  1499     @{class_syntax NAME}  -- syntax representation of the above
  1500 
  1501     @{type_name NAME}     -- logical type
  1502     @{type_abbrev NAME}   -- type abbreviation
  1503     @{nonterminal NAME}   -- type of concrete syntactic category
  1504     @{type_syntax NAME}   -- syntax representation of any of the above
  1505 
  1506     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  1507     @{const_abbrev NAME}  -- abbreviated constant
  1508     @{const_syntax NAME}  -- syntax representation of any of the above
  1509 
  1510 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  1511 syntax constant (cf. 'syntax' command).
  1512 
  1513 * Antiquotation @{make_string} inlines a function to print arbitrary
  1514 values similar to the ML toplevel.  The result is compiler dependent
  1515 and may fall back on "?" in certain situations.
  1516 
  1517 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  1518 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  1519 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  1520 not work with the asynchronous Isar document model.
  1521 
  1522 * Configuration options now admit dynamic default values, depending on
  1523 the context or even global references.
  1524 
  1525 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  1526 uses an efficient external library if available (for Poly/ML).
  1527 
  1528 * Renamed some important ML structures, while keeping the old names
  1529 for some time as aliases within the structure Legacy:
  1530 
  1531   OuterKeyword  ~>  Keyword
  1532   OuterLex      ~>  Token
  1533   OuterParse    ~>  Parse
  1534   OuterSyntax   ~>  Outer_Syntax
  1535   PrintMode     ~>  Print_Mode
  1536   SpecParse     ~>  Parse_Spec
  1537   ThyInfo       ~>  Thy_Info
  1538   ThyLoad       ~>  Thy_Load
  1539   ThyOutput     ~>  Thy_Output
  1540   TypeInfer     ~>  Type_Infer
  1541 
  1542 Note that "open Legacy" simplifies porting of sources, but forgetting
  1543 to remove it again will complicate porting again in the future.
  1544 
  1545 * Most operations that refer to a global context are named
  1546 accordingly, e.g. Simplifier.global_context or
  1547 ProofContext.init_global.  There are some situations where a global
  1548 context actually works, but under normal circumstances one needs to
  1549 pass the proper local context through the code!
  1550 
  1551 * Discontinued old TheoryDataFun with its copy/init operation -- data
  1552 needs to be pure.  Functor Theory_Data_PP retains the traditional
  1553 Pretty.pp argument to merge, which is absent in the standard
  1554 Theory_Data version.
  1555 
  1556 * Sorts.certify_sort and derived "cert" operations for types and terms
  1557 no longer minimize sorts.  Thus certification at the boundary of the
  1558 inference kernel becomes invariant under addition of class relations,
  1559 which is an important monotonicity principle.  Sorts are now minimized
  1560 in the syntax layer only, at the boundary between the end-user and the
  1561 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  1562 explicitly in rare situations.
  1563 
  1564 * Renamed old-style Drule.standard to Drule.export_without_context, to
  1565 emphasize that this is in no way a standard operation.
  1566 INCOMPATIBILITY.
  1567 
  1568 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  1569 usual for resolution.  Rare INCOMPATIBILITY.
  1570 
  1571 * Renamed varify/unvarify operations to varify_global/unvarify_global
  1572 to emphasize that these only work in a global situation (which is
  1573 quite rare).
  1574 
  1575 * Curried take and drop in library.ML; negative length is interpreted
  1576 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  1577 
  1578 * Proof terms: type substitutions on proof constants now use canonical
  1579 order of type variables.  INCOMPATIBILITY for tools working with proof
  1580 terms.
  1581 
  1582 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  1583 may no longer carry premises.  User-level specifications are
  1584 transformed accordingly by Thm.add_axiom/add_def.
  1585 
  1586 
  1587 *** System ***
  1588 
  1589 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  1590 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  1591 proof terms are enabled unconditionally in the new HOL-Proofs image.
  1592 
  1593 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  1594 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  1595 respectively.
  1596 
  1597 * Old lib/scripts/polyml-platform is superseded by the
  1598 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  1599 variant, even on a 64 bit machine.  The following example setting
  1600 prefers 64 bit if available:
  1601 
  1602   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  1603 
  1604 * The preliminary Isabelle/jEdit application demonstrates the emerging
  1605 Isabelle/Scala layer for advanced prover interaction and integration.
  1606 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  1607 component.
  1608 
  1609 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  1610 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  1611 similar to the default assignment of the document preparation system
  1612 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  1613 provides some operations for direct access to the font without asking
  1614 the user for manual installation.
  1615 
  1616 
  1617 
  1618 New in Isabelle2009-1 (December 2009)
  1619 -------------------------------------
  1620 
  1621 *** General ***
  1622 
  1623 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  1624 one backslash should be used, even in ML sources.
  1625 
  1626 
  1627 *** Pure ***
  1628 
  1629 * Locale interpretation propagates mixins along the locale hierarchy.
  1630 The currently only available mixins are the equations used to map
  1631 local definitions to terms of the target domain of an interpretation.
  1632 
  1633 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  1634 loc" to print all interpretations of locale "loc" in the theory.
  1635 Interpretations in proofs are not shown.
  1636 
  1637 * Thoroughly revised locales tutorial.  New section on conditional
  1638 interpretation.
  1639 
  1640 * On instantiation of classes, remaining undefined class parameters
  1641 are formally declared.  INCOMPATIBILITY.
  1642 
  1643 
  1644 *** Document preparation ***
  1645 
  1646 * New generalized style concept for printing terms: @{foo (style) ...}
  1647 instead of @{foo_style style ...}  (old form is still retained for
  1648 backward compatibility).  Styles can be also applied for
  1649 antiquotations prop, term_type and typeof.
  1650 
  1651 
  1652 *** HOL ***
  1653 
  1654 * New proof method "smt" for a combination of first-order logic with
  1655 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  1656 fixed-size bitvectors; there is also basic support for higher-order
  1657 features (esp. lambda abstractions).  It is an incomplete decision
  1658 procedure based on external SMT solvers using the oracle mechanism;
  1659 for the SMT solver Z3, this method is proof-producing.  Certificates
  1660 are provided to avoid calling the external solvers solely for
  1661 re-checking proofs.  Due to a remote SMT service there is no need for
  1662 installing SMT solvers locally.  See src/HOL/SMT.
  1663 
  1664 * New commands to load and prove verification conditions generated by
  1665 the Boogie program verifier or derived systems (e.g. the Verifying C
  1666 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1667 
  1668 * New counterexample generator tool 'nitpick' based on the Kodkod
  1669 relational model finder.  See src/HOL/Tools/Nitpick and
  1670 src/HOL/Nitpick_Examples.
  1671 
  1672 * New commands 'code_pred' and 'values' to invoke the predicate
  1673 compiler and to enumerate values of inductive predicates.
  1674 
  1675 * A tabled implementation of the reflexive transitive closure.
  1676 
  1677 * New implementation of quickcheck uses generic code generator;
  1678 default generators are provided for all suitable HOL types, records
  1679 and datatypes.  Old quickcheck can be re-activated importing theory
  1680 Library/SML_Quickcheck.
  1681 
  1682 * New testing tool Mirabelle for automated proof tools.  Applies
  1683 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1684 every proof step in a theory.  To be used in batch mode via the
  1685 "mirabelle" utility.
  1686 
  1687 * New proof method "sos" (sum of squares) for nonlinear real
  1688 arithmetic (originally due to John Harison). It requires theory
  1689 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1690 works well in practice on quantifier-free real arithmetic with +, -,
  1691 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1692 inequalities between polynomials.  It makes use of external
  1693 semidefinite programming solvers.  Method "sos" generates a
  1694 certificate that can be pasted into the proof thus avoiding the need
  1695 to call an external tool every time the proof is checked.  See
  1696 src/HOL/Library/Sum_Of_Squares.
  1697 
  1698 * New method "linarith" invokes existing linear arithmetic decision
  1699 procedure only.
  1700 
  1701 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1702 
  1703 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1704 Causes full type information to be output to the ATPs.  This slows
  1705 ATPs down considerably but eliminates a source of unsound "proofs"
  1706 that fail later.
  1707 
  1708 * New method "metisFT": A version of metis that uses full type
  1709 information in order to avoid failures of proof reconstruction.
  1710 
  1711 * New evaluator "approximate" approximates an real valued term using
  1712 the same method as the approximation method.
  1713 
  1714 * Method "approximate" now supports arithmetic expressions as
  1715 boundaries of intervals and implements interval splitting and Taylor
  1716 series expansion.
  1717 
  1718 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1719 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1720 
  1721 * New theory SupInf of the supremum and infimum operators for sets of
  1722 reals.
  1723 
  1724 * New theory Probability, which contains a development of measure
  1725 theory, eventually leading to Lebesgue integration and probability.
  1726 
  1727 * Extended Multivariate Analysis to include derivation and Brouwer's
  1728 fixpoint theorem.
  1729 
  1730 * Reorganization of number theory, INCOMPATIBILITY:
  1731   - new number theory development for nat and int, in theories Divides
  1732     and GCD as well as in new session Number_Theory
  1733   - some constants and facts now suffixed with _nat and _int
  1734     accordingly
  1735   - former session NumberTheory now named Old_Number_Theory, including
  1736     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1737   - moved theory Pocklington from src/HOL/Library to
  1738     src/HOL/Old_Number_Theory
  1739 
  1740 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1741 lcm of finite and infinite sets. It is shown that they form a complete
  1742 lattice.
  1743 
  1744 * Class semiring_div requires superclass no_zero_divisors and proof of
  1745 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1746 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1747 generalized to class semiring_div, subsuming former theorems
  1748 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1749 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1750 INCOMPATIBILITY.
  1751 
  1752 * Refinements to lattice classes and sets:
  1753   - less default intro/elim rules in locale variant, more default
  1754     intro/elim rules in class variant: more uniformity
  1755   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1756     le_inf_iff
  1757   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1758     sup_aci)
  1759   - renamed ACI to inf_sup_aci
  1760   - new class "boolean_algebra"
  1761   - class "complete_lattice" moved to separate theory
  1762     "Complete_Lattice"; corresponding constants (and abbreviations)
  1763     renamed and with authentic syntax:
  1764     Set.Inf ~>    Complete_Lattice.Inf
  1765     Set.Sup ~>    Complete_Lattice.Sup
  1766     Set.INFI ~>   Complete_Lattice.INFI
  1767     Set.SUPR ~>   Complete_Lattice.SUPR
  1768     Set.Inter ~>  Complete_Lattice.Inter
  1769     Set.Union ~>  Complete_Lattice.Union
  1770     Set.INTER ~>  Complete_Lattice.INTER
  1771     Set.UNION ~>  Complete_Lattice.UNION
  1772   - authentic syntax for
  1773     Set.Pow
  1774     Set.image
  1775   - mere abbreviations:
  1776     Set.empty               (for bot)
  1777     Set.UNIV                (for top)
  1778     Set.inter               (for inf, formerly Set.Int)
  1779     Set.union               (for sup, formerly Set.Un)
  1780     Complete_Lattice.Inter  (for Inf)
  1781     Complete_Lattice.Union  (for Sup)
  1782     Complete_Lattice.INTER  (for INFI)
  1783     Complete_Lattice.UNION  (for SUPR)
  1784   - object-logic definitions as far as appropriate
  1785 
  1786 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1787 Un_subset_iff are explicitly deleted as default simp rules; then also
  1788 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1789 deleted to achieve the desired effect.
  1790 
  1791 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1792 rules by default any longer; the same applies to min_max.inf_absorb1
  1793 etc.  INCOMPATIBILITY.
  1794 
  1795 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1796 pred_set_conv by default.  INCOMPATIBILITY.
  1797 
  1798 * Power operations on relations and functions are now one dedicated
  1799 constant "compow" with infix syntax "^^".  Power operation on
  1800 multiplicative monoids retains syntax "^" and is now defined generic
  1801 in class power.  INCOMPATIBILITY.
  1802 
  1803 * Relation composition "R O S" now has a more standard argument order:
  1804 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1805 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1806 break, since the O_assoc rule was not rewritten like this.  Fix using
  1807 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1808 
  1809 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1810 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1811 INCOMPATIBILITY.
  1812 
  1813 * Most rules produced by inductive and datatype package have mandatory
  1814 prefixes.  INCOMPATIBILITY.
  1815 
  1816 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1817 the attribute of the same name.  Each of the theorems in the list
  1818 DERIV_intros assumes composition with an additional function and
  1819 matches a variable to the derivative, which has to be solved by the
  1820 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1821 of most elementary terms.  Former Maclauren.DERIV_tac and
  1822 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1823 INCOMPATIBILITY.
  1824 
  1825 * Code generator attributes follow the usual underscore convention:
  1826     code_unfold     replaces    code unfold
  1827     code_post       replaces    code post
  1828     etc.
  1829   INCOMPATIBILITY.
  1830 
  1831 * Renamed methods:
  1832     sizechange -> size_change
  1833     induct_scheme -> induction_schema
  1834   INCOMPATIBILITY.
  1835 
  1836 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1837 INCOMPATIBILITY, use "undefined" directly.
  1838 
  1839 * Renamed theorems:
  1840     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1841     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1842     Suc_plus1 -> Suc_eq_plus1
  1843     *anti_sym -> *antisym*
  1844     vector_less_eq_def -> vector_le_def
  1845   INCOMPATIBILITY.
  1846 
  1847 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1848 INCOMPATIBILITY.
  1849 
  1850 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1851 INCOMPATIBILITY.
  1852 
  1853 
  1854 *** HOLCF ***
  1855 
  1856 * Theory Representable defines a class "rep" of domains that are
  1857 representable (via an ep-pair) in the universal domain type "udom".
  1858 Instances are provided for all type constructors defined in HOLCF.
  1859 
  1860 * The 'new_domain' command is a purely definitional version of the
  1861 domain package, for representable domains.  Syntax is identical to the
  1862 old domain package.  The 'new_domain' package also supports indirect
  1863 recursion using previously-defined type constructors.  See
  1864 src/HOLCF/ex/New_Domain.thy for examples.
  1865 
  1866 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1867 on the left-hand side of an equation, and then performs
  1868 simplification.  Rewriting is done using rules declared with the
  1869 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1870 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1871 
  1872 * The pattern-match compiler in 'fixrec' can now handle constructors
  1873 with HOL function types.  Pattern-match combinators for the Pair
  1874 constructor are pre-configured.
  1875 
  1876 * The 'fixrec' package now produces better fixed-point induction rules
  1877 for mutually-recursive definitions:  Induction rules have conclusions
  1878 of the form "P foo bar" instead of "P <foo, bar>".
  1879 
  1880 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1881 been renamed to "below".  The name "below" now replaces "less" in many
  1882 theorem names.  (Legacy theorem names using "less" are still supported
  1883 as well.)
  1884 
  1885 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1886 patterns can be used to generate strictness rules, or to make
  1887 functions more strict (much like the bang-patterns supported by the
  1888 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1889 examples.
  1890 
  1891 
  1892 *** ML ***
  1893 
  1894 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1895 errors and run-time exceptions, including detailed source positions.
  1896 
  1897 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1898 identified entries, with some additional information such as source
  1899 position, logical grouping etc.
  1900 
  1901 * Theory and context data is now introduced by the simplified and
  1902 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1903 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1904 copy operation) is still available for some time.
  1905 
  1906 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1907 provides a high-level programming interface to synchronized state
  1908 variables with atomic update.  This works via pure function
  1909 application within a critical section -- its runtime should be as
  1910 short as possible; beware of deadlocks if critical code is nested,
  1911 either directly or indirectly via other synchronized variables!
  1912 
  1913 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1914 wraps raw ML references, explicitly indicating their non-thread-safe
  1915 behaviour.  The Isar toplevel keeps this structure open, to
  1916 accommodate Proof General as well as quick and dirty interactive
  1917 experiments with references.
  1918 
  1919 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1920 parallel tactical reasoning.
  1921 
  1922 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1923 are similar to SUBPROOF, but are slightly more flexible: only the
  1924 specified parts of the subgoal are imported into the context, and the
  1925 body tactic may introduce new subgoals and schematic variables.
  1926 
  1927 * Old tactical METAHYPS, which does not observe the proof context, has
  1928 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1929 or Subgoal.FOCUS etc.
  1930 
  1931 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  1932 functors have their own ML name space there is no point to mark them
  1933 separately.)  Minor INCOMPATIBILITY.
  1934 
  1935 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  1936 
  1937 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  1938 INCOMPATIBILITY.
  1939 
  1940 * Operations of structure Skip_Proof no longer require quick_and_dirty
  1941 mode, which avoids critical setmp.
  1942 
  1943 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  1944 combinators for "args".  INCOMPATIBILITY, need to use simplified
  1945 Attrib/Method.setup introduced in Isabelle2009.
  1946 
  1947 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  1948 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  1949 last resort.  INCOMPATIBILITY.
  1950 
  1951 * Display.pretty_thm now requires a proper context (cf. former
  1952 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  1953 or even Display.pretty_thm_without_context as last resort.
  1954 INCOMPATIBILITY.
  1955 
  1956 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  1957 Syntax.pretty_typ/term directly, preferably with proper context
  1958 instead of global theory.
  1959 
  1960 
  1961 *** System ***
  1962 
  1963 * Further fine tuning of parallel proof checking, scales up to 8 cores
  1964 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  1965 usedir option -q.
  1966 
  1967 * Support for additional "Isabelle components" via etc/components, see
  1968 also the system manual.
  1969 
  1970 * The isabelle makeall tool now operates on all components with
  1971 IsaMakefile, not just hardwired "logics".
  1972 
  1973 * Removed "compress" option from isabelle-process and isabelle usedir;
  1974 this is always enabled.
  1975 
  1976 * Discontinued support for Poly/ML 4.x versions.
  1977 
  1978 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  1979 on a given logic image.  This requires the lighttpd webserver and is
  1980 currently supported on Linux only.
  1981 
  1982 
  1983 
  1984 New in Isabelle2009 (April 2009)
  1985 --------------------------------
  1986 
  1987 *** General ***
  1988 
  1989 * Simplified main Isabelle executables, with less surprises on
  1990 case-insensitive file-systems (such as Mac OS).
  1991 
  1992   - The main Isabelle tool wrapper is now called "isabelle" instead of
  1993     "isatool."
  1994 
  1995   - The former "isabelle" alias for "isabelle-process" has been
  1996     removed (should rarely occur to regular users).
  1997 
  1998   - The former "isabelle-interface" and its alias "Isabelle" have been
  1999     removed (interfaces are now regular Isabelle tools).
  2000 
  2001 Within scripts and make files, the Isabelle environment variables
  2002 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  2003 respectively.  (The latter are still available as legacy feature.)
  2004 
  2005 The old isabelle-interface wrapper could react in confusing ways if
  2006 the interface was uninstalled or changed otherwise.  Individual
  2007 interface tool configuration is now more explicit, see also the
  2008 Isabelle system manual.  In particular, Proof General is now available
  2009 via "isabelle emacs".
  2010 
  2011 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  2012 purge installed copies of Isabelle executables and re-run "isabelle
  2013 install -p ...", or use symlinks.
  2014 
  2015 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  2016 old ~/isabelle, which was slightly non-standard and apt to cause
  2017 surprises on case-insensitive file-systems (such as Mac OS).
  2018 
  2019 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  2020 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  2021 care is required when using older releases of Isabelle.  Note that
  2022 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  2023 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  2024 
  2025 * Proofs of fully specified statements are run in parallel on
  2026 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  2027 a regular 4-core machine, if the initial heap space is made reasonably
  2028 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  2029 
  2030 * The main reference manuals ("isar-ref", "implementation", and
  2031 "system") have been updated and extended.  Formally checked references
  2032 as hyperlinks are now available uniformly.
  2033 
  2034 
  2035 *** Pure ***
  2036 
  2037 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  2038 respects.  The most important changes are listed below.  See the
  2039 Tutorial on Locales ("locales" manual) for details.
  2040 
  2041 - In locale expressions, instantiation replaces renaming.  Parameters
  2042 must be declared in a for clause.  To aid compatibility with previous
  2043 parameter inheritance, in locale declarations, parameters that are not
  2044 'touched' (instantiation position "_" or omitted) are implicitly added
  2045 with their syntax at the beginning of the for clause.
  2046 
  2047 - Syntax from abbreviations and definitions in locales is available in
  2048 locale expressions and context elements.  The latter is particularly
  2049 useful in locale declarations.
  2050 
  2051 - More flexible mechanisms to qualify names generated by locale
  2052 expressions.  Qualifiers (prefixes) may be specified in locale
  2053 expressions, and can be marked as mandatory (syntax: "name!:") or
  2054 optional (syntax "name?:").  The default depends for plain "name:"
  2055 depends on the situation where a locale expression is used: in
  2056 commands 'locale' and 'sublocale' prefixes are optional, in
  2057 'interpretation' and 'interpret' prefixes are mandatory.  The old
  2058 implicit qualifiers derived from the parameter names of a locale are
  2059 no longer generated.
  2060 
  2061 - Command "sublocale l < e" replaces "interpretation l < e".  The
  2062 instantiation clause in "interpretation" and "interpret" (square
  2063 brackets) is no longer available.  Use locale expressions.
  2064 
  2065 - When converting proof scripts, mandatory qualifiers in
  2066 'interpretation' and 'interpret' should be retained by default, even
  2067 if this is an INCOMPATIBILITY compared to former behavior.  In the
  2068 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  2069 in locale expressions range over a single locale instance only.
  2070 
  2071 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  2072 In existing theorem specifications replace the includes element by the
  2073 respective context elements of the included locale, omitting those
  2074 that are already present in the theorem specification.  Multiple
  2075 assume elements of a locale should be replaced by a single one
  2076 involving the locale predicate.  In the proof body, declarations (most
  2077 notably theorems) may be regained by interpreting the respective
  2078 locales in the proof context as required (command "interpret").
  2079 
  2080 If using "includes" in replacement of a target solely because the
  2081 parameter types in the theorem are not as general as in the target,
  2082 consider declaring a new locale with additional type constraints on
  2083 the parameters (context element "constrains").
  2084 
  2085 - Discontinued "locale (open)".  INCOMPATIBILITY.
  2086 
  2087 - Locale interpretation commands no longer attempt to simplify goal.
  2088 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  2089 methods intro_locales and unfold_locales to clarify.
  2090 
  2091 - Locale interpretation commands no longer accept interpretation
  2092 attributes.  INCOMPATIBILITY.
  2093 
  2094 * Class declaration: so-called "base sort" must not be given in import
  2095 list any longer, but is inferred from the specification.  Particularly
  2096 in HOL, write
  2097 
  2098     class foo = ...
  2099 
  2100 instead of
  2101 
  2102     class foo = type + ...
  2103 
  2104 * Class target: global versions of theorems stemming do not carry a
  2105 parameter prefix any longer.  INCOMPATIBILITY.
  2106 
  2107 * Class 'instance' command no longer accepts attached definitions.
  2108 INCOMPATIBILITY, use proper 'instantiation' target instead.
  2109 
  2110 * Recovered hiding of consts, which was accidentally broken in
  2111 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  2112 makes c inaccessible; consider using ``hide (open) const c'' instead.
  2113 
  2114 * Slightly more coherent Pure syntax, with updated documentation in
  2115 isar-ref manual.  Removed locales meta_term_syntax and
  2116 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  2117 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  2118 directly in regular applications.
  2119 
  2120 * There is a new syntactic category "float_const" for signed decimal
  2121 fractions (e.g. 123.45 or -123.45).
  2122 
  2123 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  2124 interface with 'setup' command instead.
  2125 
  2126 * Command 'local_setup' is similar to 'setup', but operates on a local
  2127 theory context.
  2128 
  2129 * The 'axiomatization' command now only works within a global theory
  2130 context.  INCOMPATIBILITY.
  2131 
  2132 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  2133 hypotheses.  Sorts required in the course of reasoning need to be
  2134 covered by the constraints in the initial statement, completed by the
  2135 type instance information of the background theory.  Non-trivial sort
  2136 hypotheses, which rarely occur in practice, may be specified via
  2137 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  2138 
  2139   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  2140 
  2141 The result contains an implicit sort hypotheses as before --
  2142 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  2143 normalization.
  2144 
  2145 * Generalized Isar history, with support for linear undo, direct state
  2146 addressing etc.
  2147 
  2148 * Changed defaults for unify configuration options:
  2149 
  2150   unify_trace_bound = 50 (formerly 25)
  2151   unify_search_bound = 60 (formerly 30)
  2152 
  2153 * Different bookkeeping for code equations (INCOMPATIBILITY):
  2154 
  2155   a) On theory merge, the last set of code equations for a particular
  2156      constant is taken (in accordance with the policy applied by other
  2157      parts of the code generator framework).
  2158 
  2159   b) Code equations stemming from explicit declarations (e.g. code
  2160      attribute) gain priority over default code equations stemming
  2161      from definition, primrec, fun etc.
  2162 
  2163 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  2164 
  2165 * Unified theorem tables for both code generators.  Thus [code
  2166 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  2167 
  2168 * Command 'find_consts' searches for constants based on type and name
  2169 patterns, e.g.
  2170 
  2171     find_consts "_ => bool"
  2172 
  2173 By default, matching is against subtypes, but it may be restricted to
  2174 the whole type.  Searching by name is possible.  Multiple queries are
  2175 conjunctive and queries may be negated by prefixing them with a
  2176 hyphen:
  2177 
  2178     find_consts strict: "_ => bool" name: "Int" -"int => int"
  2179 
  2180 * New 'find_theorems' criterion "solves" matches theorems that
  2181 directly solve the current goal (modulo higher-order unification).
  2182 
  2183 * Auto solve feature for main theorem statements: whenever a new goal
  2184 is stated, "find_theorems solves" is called; any theorems that could
  2185 solve the lemma directly are listed as part of the goal state.
  2186 Cf. associated options in Proof General Isabelle settings menu,
  2187 enabled by default, with reasonable timeout for pathological cases of
  2188 higher-order unification.
  2189 
  2190 
  2191 *** Document preparation ***
  2192 
  2193 * Antiquotation @{lemma} now imitates a regular terminal proof,
  2194 demanding keyword 'by' and supporting the full method expression
  2195 syntax just like the Isar command 'by'.
  2196 
  2197 
  2198 *** HOL ***
  2199 
  2200 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  2201 points Main and Complex_Main remain as before.
  2202 
  2203 * Logic image HOL-Plain provides a minimal HOL with the most important
  2204 tools available (inductive, datatype, primrec, ...).  This facilitates
  2205 experimentation and tool development.  Note that user applications
  2206 (and library theories) should never refer to anything below theory
  2207 Main, as before.
  2208 
  2209 * Logic image HOL-Main stops at theory Main, and thus facilitates
  2210 experimentation due to shorter build times.
  2211 
  2212 * Logic image HOL-NSA contains theories of nonstandard analysis which
  2213 were previously part of former HOL-Complex.  Entry point Hyperreal
  2214 remains valid, but theories formerly using Complex_Main should now use
  2215 new entry point Hypercomplex.
  2216 
  2217 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  2218 Posix processes.  Avoids potentially expensive forking of the ML
  2219 process.  New thread-based implementation also works on non-Unix
  2220 platforms (Cygwin).  Provers are no longer hardwired, but defined
  2221 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  2222 commands are covered in the isar-ref manual.
  2223 
  2224 * Wrapper scripts for remote SystemOnTPTP service allows to use
  2225 sledgehammer without local ATP installation (Vampire etc.). Other
  2226 provers may be included via suitable ML wrappers, see also
  2227 src/HOL/ATP_Linkup.thy.
  2228 
  2229 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  2230 menu.
  2231 
  2232 * The metis method no longer fails because the theorem is too trivial
  2233 (contains the empty clause).
  2234 
  2235 * The metis method now fails in the usual manner, rather than raising
  2236 an exception, if it determines that it cannot prove the theorem.
  2237 
  2238 * Method "coherent" implements a prover for coherent logic (see also
  2239 src/Tools/coherent.ML).
  2240 
  2241 * Constants "undefined" and "default" replace "arbitrary".  Usually
  2242 "undefined" is the right choice to replace "arbitrary", though
  2243 logically there is no difference.  INCOMPATIBILITY.
  2244 
  2245 * Command "value" now integrates different evaluation mechanisms.  The
  2246 result of the first successful evaluation mechanism is printed.  In
  2247 square brackets a particular named evaluation mechanisms may be
  2248 specified (currently, [SML], [code] or [nbe]).  See further
  2249 src/HOL/ex/Eval_Examples.thy.
  2250 
  2251 * Normalization by evaluation now allows non-leftlinear equations.
  2252 Declare with attribute [code nbe].
  2253 
  2254 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  2255 as the structured Isar versions "cases" and "induct", cf. the
  2256 corresponding "cases" and "induct" attributes.  Mutual induction rules
  2257 are now presented as a list of individual projections
  2258 (e.g. foo_bar.inducts for types foo and bar); the old format with
  2259 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  2260 rare situations a different rule is selected --- notably nested tuple
  2261 elimination instead of former prod.exhaust: use explicit (case_tac t
  2262 rule: prod.exhaust) here.
  2263 
  2264 * Attributes "cases", "induct", "coinduct" support "del" option.
  2265 
  2266 * Removed fact "case_split_thm", which duplicates "case_split".
  2267 
  2268 * The option datatype has been moved to a new theory Option.  Renamed
  2269 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  2270 
  2271 * New predicate "strict_mono" classifies strict functions on partial
  2272 orders.  With strict functions on linear orders, reasoning about
  2273 (in)equalities is facilitated by theorems "strict_mono_eq",
  2274 "strict_mono_less_eq" and "strict_mono_less".
  2275 
  2276 * Some set operations are now proper qualified constants with
  2277 authentic syntax.  INCOMPATIBILITY:
  2278 
  2279     op Int ~>   Set.Int
  2280     op Un ~>    Set.Un
  2281     INTER ~>    Set.INTER
  2282     UNION ~>    Set.UNION
  2283     Inter ~>    Set.Inter
  2284     Union ~>    Set.Union
  2285     {} ~>       Set.empty
  2286     UNIV ~>     Set.UNIV
  2287 
  2288 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  2289 theory Set.
  2290 
  2291 * Auxiliary class "itself" has disappeared -- classes without any
  2292 parameter are treated as expected by the 'class' command.
  2293 
  2294 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  2295 
  2296 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  2297 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  2298 
  2299 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  2300 method "approximation".  It proves formulas on real values by using
  2301 interval arithmetic.  In the formulas are also the transcendental
  2302 functions sin, cos, tan, atan, ln, exp and the constant pi are
  2303 allowed. For examples see
  2304 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  2305 
  2306 * Theory "Reflection" now resides in HOL/Library.
  2307 
  2308 * Entry point to Word library now simply named "Word".
  2309 INCOMPATIBILITY.
  2310 
  2311 * Made source layout more coherent with logical distribution
  2312 structure:
  2313 
  2314     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  2315     src/HOL/Library/Code_Message.thy ~> src/HOL/
  2316     src/HOL/Library/GCD.thy ~> src/HOL/
  2317     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  2318     src/HOL/Library/Parity.thy ~> src/HOL/
  2319     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  2320     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  2321     src/HOL/Real/Lubs.thy ~> src/HOL/
  2322     src/HOL/Real/PReal.thy ~> src/HOL/
  2323     src/HOL/Real/Rational.thy ~> src/HOL/
  2324     src/HOL/Real/RComplete.thy ~> src/HOL/
  2325     src/HOL/Real/RealDef.thy ~> src/HOL/
  2326     src/HOL/Real/RealPow.thy ~> src/HOL/
  2327     src/HOL/Real/Real.thy ~> src/HOL/
  2328     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  2329     src/HOL/Complex/Complex.thy ~> src/HOL/
  2330     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  2331     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  2332     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  2333     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  2334     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  2335     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  2336     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  2337     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  2338     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  2339     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  2340     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  2341     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  2342     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  2343     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  2344     src/HOL/Real/Float ~> src/HOL/Library/
  2345     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  2346     src/HOL/Real/RealVector.thy ~> src/HOL/
  2347 
  2348     src/HOL/arith_data.ML ~> src/HOL/Tools
  2349     src/HOL/hologic.ML ~> src/HOL/Tools
  2350     src/HOL/simpdata.ML ~> src/HOL/Tools
  2351     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  2352     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  2353     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  2354     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  2355     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  2356     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  2357     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  2358 
  2359     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  2360     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  2361     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  2362     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  2363     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  2364     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  2365 
  2366 * If methods "eval" and "evaluation" encounter a structured proof
  2367 state with !!/==>, only the conclusion is evaluated to True (if
  2368 possible), avoiding strange error messages.
  2369 
  2370 * Method "sizechange" automates termination proofs using (a
  2371 modification of) the size-change principle.  Requires SAT solver.  See
  2372 src/HOL/ex/Termination.thy for examples.
  2373 
  2374 * Simplifier: simproc for let expressions now unfolds if bound
  2375 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  2376 
  2377 * Method "arith": Linear arithmetic now ignores all inequalities when
  2378 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  2379 
  2380 * New attribute "arith" for facts that should always be used
  2381 automatically by arithmetic. It is intended to be used locally in
  2382 proofs, e.g.
  2383 
  2384   assumes [arith]: "x > 0"
  2385 
  2386 Global usage is discouraged because of possible performance impact.
  2387 
  2388 * New classes "top" and "bot" with corresponding operations "top" and
  2389 "bot" in theory Orderings; instantiation of class "complete_lattice"
  2390 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  2391 
  2392 * Changed definition lemma "less_fun_def" in order to provide an
  2393 instance for preorders on functions; use lemma "less_le" instead.
  2394 INCOMPATIBILITY.
  2395 
  2396 * Theory Orderings: class "wellorder" moved here, with explicit
  2397 induction rule "less_induct" as assumption.  For instantiation of
  2398 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  2399 INCOMPATIBILITY.
  2400 
  2401 * Theory Orderings: added class "preorder" as superclass of "order".
  2402 INCOMPATIBILITY: Instantiation proofs for order, linorder
  2403 etc. slightly changed.  Some theorems named order_class.* now named
  2404 preorder_class.*.
  2405 
  2406 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  2407 "diag" to "Id_on".
  2408 
  2409 * Theory Finite_Set: added a new fold combinator of type
  2410 
  2411   ('a => 'b => 'b) => 'b => 'a set => 'b
  2412 
  2413 Occasionally this is more convenient than the old fold combinator
  2414 which is now defined in terms of the new one and renamed to
  2415 fold_image.
  2416 
  2417 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  2418 and "ring_simps" have been replaced by "algebra_simps" (which can be
  2419 extended with further lemmas!).  At the moment both still exist but
  2420 the former will disappear at some point.
  2421 
  2422 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  2423 class recpower.  Type-specific simp rules for various recpower types
  2424 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  2425 
  2426 rat_power_0    -> power_0
  2427 rat_power_Suc  -> power_Suc
  2428 realpow_0      -> power_0
  2429 realpow_Suc    -> power_Suc
  2430 complexpow_0   -> power_0
  2431 complexpow_Suc -> power_Suc
  2432 power_poly_0   -> power_0
  2433 power_poly_Suc -> power_Suc
  2434 
  2435 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  2436 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  2437 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  2438 of lemmas from Divides has been generalized from nat to class
  2439 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  2440 renames resulting from duplicate elimination:
  2441 
  2442     dvd_def_mod ~>          dvd_eq_mod_eq_0
  2443     zero_dvd_iff ~>         dvd_0_left_iff
  2444     dvd_0 ~>                dvd_0_right
  2445     DIVISION_BY_ZERO_DIV ~> div_by_0
  2446     DIVISION_BY_ZERO_MOD ~> mod_by_0
  2447     mult_div ~>             div_mult_self2_is_id
  2448     mult_mod ~>             mod_mult_self2_is_0
  2449 
  2450 * Theory IntDiv: removed many lemmas that are instances of class-based
  2451 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  2452 rename old lemmas as follows:
  2453 
  2454 dvd_diff               -> nat_dvd_diff
  2455 dvd_zminus_iff         -> dvd_minus_iff
  2456 mod_add1_eq            -> mod_add_eq
  2457 mod_mult1_eq           -> mod_mult_right_eq
  2458 mod_mult1_eq'          -> mod_mult_left_eq
  2459 mod_mult_distrib_mod   -> mod_mult_eq
  2460 nat_mod_add_left_eq    -> mod_add_left_eq
  2461 nat_mod_add_right_eq   -> mod_add_right_eq
  2462 nat_mod_div_trivial    -> mod_div_trivial
  2463 nat_mod_mod_trivial    -> mod_mod_trivial
  2464 zdiv_zadd_self1        -> div_add_self1
  2465 zdiv_zadd_self2        -> div_add_self2
  2466 zdiv_zmult_self1       -> div_mult_self2_is_id
  2467 zdiv_zmult_self2       -> div_mult_self1_is_id
  2468 zdvd_triv_left         -> dvd_triv_left
  2469 zdvd_triv_right        -> dvd_triv_right
  2470 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  2471 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  2472 zmod_zadd_left_eq      -> mod_add_left_eq
  2473 zmod_zadd_right_eq     -> mod_add_right_eq
  2474 zmod_zadd_self1        -> mod_add_self1
  2475 zmod_zadd_self2        -> mod_add_self2
  2476 zmod_zadd1_eq          -> mod_add_eq
  2477 zmod_zdiff1_eq         -> mod_diff_eq
  2478 zmod_zdvd_zmod         -> mod_mod_cancel
  2479 zmod_zmod_cancel       -> mod_mod_cancel
  2480 zmod_zmult_self1       -> mod_mult_self2_is_0
  2481 zmod_zmult_self2       -> mod_mult_self1_is_0
  2482 zmod_1                 -> mod_by_1
  2483 zdiv_1                 -> div_by_1
  2484 zdvd_abs1              -> abs_dvd_iff
  2485 zdvd_abs2              -> dvd_abs_iff
  2486 zdvd_refl              -> dvd_refl
  2487 zdvd_trans             -> dvd_trans
  2488 zdvd_zadd              -> dvd_add
  2489 zdvd_zdiff             -> dvd_diff
  2490 zdvd_zminus_iff        -> dvd_minus_iff
  2491 zdvd_zminus2_iff       -> minus_dvd_iff
  2492 zdvd_zmultD            -> dvd_mult_right
  2493 zdvd_zmultD2           -> dvd_mult_left
  2494 zdvd_zmult_mono        -> mult_dvd_mono
  2495 zdvd_0_right           -> dvd_0_right
  2496 zdvd_0_left            -> dvd_0_left_iff
  2497 zdvd_1_left            -> one_dvd
  2498 zminus_dvd_iff         -> minus_dvd_iff
  2499 
  2500 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  2501 
  2502 * The real numbers offer decimal input syntax: 12.34 is translated
  2503 into 1234/10^2. This translation is not reversed upon output.
  2504 
  2505 * Theory Library/Polynomial defines an abstract type 'a poly of
  2506 univariate polynomials with coefficients of type 'a.  In addition to
  2507 the standard ring operations, it also supports div and mod.  Code
  2508 generation is also supported, using list-style constructors.
  2509 
  2510 * Theory Library/Inner_Product defines a class of real_inner for real
  2511 inner product spaces, with an overloaded operation inner :: 'a => 'a
  2512 => real.  Class real_inner is a subclass of real_normed_vector from
  2513 theory RealVector.
  2514 
  2515 * Theory Library/Product_Vector provides instances for the product
  2516 type 'a * 'b of several classes from RealVector and Inner_Product.
  2517 Definitions of addition, subtraction, scalar multiplication, norms,
  2518 and inner products are included.
  2519 
  2520 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  2521 addition to the field operations, numerals and case syntax are also
  2522 supported.
  2523 
  2524 * Theory Library/Diagonalize provides constructive version of Cantor's
  2525 first diagonalization argument.
  2526 
  2527 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  2528 zlcm (for int); carried together from various gcd/lcm developements in
  2529 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  2530 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  2531 may recover tupled syntax as follows:
  2532 
  2533     hide (open) const gcd
  2534     abbreviation gcd where
  2535       "gcd == (%(a, b). GCD.gcd a b)"
  2536     notation (output)
  2537       GCD.gcd ("gcd '(_, _')")
  2538 
  2539 The same works for lcm, zgcd, zlcm.
  2540 
  2541 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  2542 instantiations for algebraic structures.  Removed some duplicate
  2543 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  2544 
  2545 * ML antiquotation @{code} takes a constant as argument and generates
  2546 corresponding code in background and inserts name of the corresponding
  2547 resulting ML value/function/datatype constructor binding in place.
  2548 All occurrences of @{code} with a single ML block are generated
  2549 simultaneously.  Provides a generic and safe interface for
  2550 instrumentalizing code generation.  See
  2551 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  2552 In future you ought to refrain from ad-hoc compiling generated SML
  2553 code on the ML toplevel.  Note that (for technical reasons) @{code}
  2554 cannot refer to constants for which user-defined serializations are
  2555 set.  Refer to the corresponding ML counterpart directly in that
  2556 cases.
  2557 
  2558 * Command 'rep_datatype': instead of theorem names the command now
  2559 takes a list of terms denoting the constructors of the type to be
  2560 represented as datatype.  The characteristic theorems have to be
  2561 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  2562 have disappeared in favour of existing ones:
  2563 
  2564     unit_induct                 ~> unit.induct
  2565     prod_induct                 ~> prod.induct
  2566     sum_induct                  ~> sum.induct
  2567     Suc_Suc_eq                  ~> nat.inject
  2568     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  2569 
  2570 
  2571 *** HOL-Algebra ***
  2572 
  2573 * New locales for orders and lattices where the equivalence relation
  2574 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  2575 locales use a record structure with field eq for the equivalence.
  2576 
  2577 * New theory of factorial domains.
  2578 
  2579 * Units_l_inv and Units_r_inv are now simp rules by default.
  2580 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  2581 and/or r_inv will now also require deletion of these lemmas.
  2582 
  2583 * Renamed the following theorems, INCOMPATIBILITY:
  2584 
  2585 UpperD ~> Upper_memD
  2586 LowerD ~> Lower_memD
  2587 least_carrier ~> least_closed
  2588 greatest_carrier ~> greatest_closed
  2589 greatest_Lower_above ~> greatest_Lower_below
  2590 one_zero ~> carrier_one_zero
  2591 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  2592 
  2593 
  2594 *** HOL-Nominal ***
  2595 
  2596 * Nominal datatypes can now contain type-variables.
  2597 
  2598 * Commands 'nominal_inductive' and 'equivariance' work with local
  2599 theory targets.
  2600 
  2601 * Nominal primrec can now works with local theory targets and its
  2602 specification syntax now conforms to the general format as seen in
  2603 'inductive' etc.
  2604 
  2605 * Method "perm_simp" honours the standard simplifier attributes
  2606 (no_asm), (no_asm_use) etc.
  2607 
  2608 * The new predicate #* is defined like freshness, except that on the
  2609 left hand side can be a set or list of atoms.
  2610 
  2611 * Experimental command 'nominal_inductive2' derives strong induction
  2612 principles for inductive definitions.  In contrast to
  2613 'nominal_inductive', which can only deal with a fixed number of
  2614 binders, it can deal with arbitrary expressions standing for sets of
  2615 atoms to be avoided.  The only inductive definition we have at the
  2616 moment that needs this generalisation is the typing rule for Lets in
  2617 the algorithm W:
  2618 
  2619  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  2620  -----------------------------------------------------------------
  2621          Gamma |- Let x be t1 in t2 : T2
  2622 
  2623 In this rule one wants to avoid all the binders that are introduced by
  2624 "close Gamma T1".  We are looking for other examples where this
  2625 feature might be useful.  Please let us know.
  2626 
  2627 
  2628 *** HOLCF ***
  2629 
  2630 * Reimplemented the simplification procedure for proving continuity
  2631 subgoals.  The new simproc is extensible; users can declare additional
  2632 continuity introduction rules with the attribute [cont2cont].
  2633 
  2634 * The continuity simproc now uses a different introduction rule for
  2635 solving continuity subgoals on terms with lambda abstractions.  In
  2636 some rare cases the new simproc may fail to solve subgoals that the
  2637 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  2638 Potential INCOMPATIBILITY.
  2639 
  2640 * Command 'fixrec': specification syntax now conforms to the general
  2641 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  2642 examples.  INCOMPATIBILITY.
  2643 
  2644 
  2645 *** ZF ***
  2646 
  2647 * Proof of Zorn's Lemma for partial orders.
  2648 
  2649 
  2650 *** ML ***
  2651 
  2652 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  2653 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  2654 depends on multithreading, so timouts will not work before Poly/ML
  2655 5.2.1!
  2656 
  2657 * High-level support for concurrent ML programming, see
  2658 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  2659 particularly convenient to organize independent functional
  2660 computations.  The concept of "synchronized variables" provides a
  2661 higher-order interface for components with shared state, avoiding the
  2662 delicate details of mutexes and condition variables.  (Requires
  2663 Poly/ML 5.2.1 or later.)
  2664 
  2665 * ML bindings produced via Isar commands are stored within the Isar
  2666 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2667 become thread-safe and work with undo as expected (concerning
  2668 top-level bindings, not side-effects on global references).
  2669 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2670 compiler at runtime; really global bindings need to be given outside a
  2671 theory.  (Requires Poly/ML 5.2 or later.)
  2672 
  2673 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2674 context.  Top-level ML bindings are stored within the proof context in
  2675 a purely sequential fashion, disregarding the nested proof structure.
  2676 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2677 proof.  (Requires Poly/ML 5.2 or later.)
  2678 
  2679 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2680 and Method.setup, as well as Isar commands 'attribute_setup' and
  2681 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2682 existing code accordingly, or use plain 'setup' together with old
  2683 Method.add_method.
  2684 
  2685 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2686 to 'a -> thm, while results are always tagged with an authentic oracle
  2687 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2688 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2689 accordingly.  Note that extra performance may be gained by producing
  2690 the cterm carefully, avoiding slow Thm.cterm_of.
  2691 
  2692 * Simplified interface for defining document antiquotations via
  2693 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2694 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2695 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2696 examples.
  2697 
  2698 * More systematic treatment of long names, abstract name bindings, and
  2699 name space operations.  Basic operations on qualified names have been
  2700 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2701 Long_Name.append.  Old type bstring has been mostly replaced by
  2702 abstract type binding (see structure Binding), which supports precise
  2703 qualification by packages and local theory targets, as well as proper
  2704 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2705 bstring values into Binding.name, or better pass through abstract
  2706 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2707 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2708 
  2709 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2710 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2711 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2712 
  2713 * Disposed old type and term read functions (Sign.read_def_typ,
  2714 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2715 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2716 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2717 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2718 resort for legacy applications.
  2719 
  2720 * Disposed old declarations, tactics, tactic combinators that refer to
  2721 the simpset or claset of an implicit theory (such as Addsimps,
  2722 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2723 embedded ML text, or local_simpset_of with a proper context passed as
  2724 explicit runtime argument.
  2725 
  2726 * Rules and tactics that read instantiations (read_instantiate,
  2727 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2728 context, which is required for parsing and type-checking.  Moreover,
  2729 the variables are specified as plain indexnames, not string encodings
  2730 thereof.  INCOMPATIBILITY.
  2731 
  2732 * Generic Toplevel.add_hook interface allows to analyze the result of
  2733 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2734 for theorem dependency output of transactions resulting in a new
  2735 theory state.
  2736 
  2737 * ML antiquotations: block-structured compilation context indicated by
  2738 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2739 
  2740   @{binding name}                         - basic name binding
  2741   @{let ?pat = term}                      - term abbreviation (HO matching)
  2742   @{note name = fact}                     - fact abbreviation
  2743   @{thm fact}                             - singleton fact (with attributes)
  2744   @{thms fact}                            - general fact (with attributes)
  2745   @{lemma prop by method}                 - singleton goal
  2746   @{lemma prop by meth1 meth2}            - singleton goal
  2747   @{lemma prop1 ... propN by method}      - general goal
  2748   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2749   @{lemma (open) ...}                     - open derivation
  2750 
  2751 
  2752 *** System ***
  2753 
  2754 * The Isabelle "emacs" tool provides a specific interface to invoke
  2755 Proof General / Emacs, with more explicit failure if that is not
  2756 installed (the old isabelle-interface script silently falls back on
  2757 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2758 installation location of the Proof General distribution.
  2759 
  2760 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2761 the Isabelle process into a JVM/Scala application.  See
  2762 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2763 process wrapper has been discontinued.)
  2764 
  2765 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2766 
  2767 * Various status messages (with exact source position information) are
  2768 emitted, if proper markup print mode is enabled.  This allows
  2769 user-interface components to provide detailed feedback on internal
  2770 prover operations.
  2771 
  2772 
  2773 
  2774 New in Isabelle2008 (June 2008)
  2775 -------------------------------
  2776 
  2777 *** General ***
  2778 
  2779 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2780 and updated, with formally checked references as hyperlinks.
  2781 
  2782 * Theory loader: use_thy (and similar operations) no longer set the
  2783 implicit ML context, which was occasionally hard to predict and in
  2784 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2785 provides a proper context already.
  2786 
  2787 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2788 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2789 'use' within a theory file will do the job.
  2790 
  2791 * Name space merge now observes canonical order, i.e. the second space
  2792 is inserted into the first one, while existing entries in the first
  2793 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2794 swap theory imports.
  2795 
  2796 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2797 INCOMPATIBILITY in identifier syntax etc.
  2798 
  2799 * Outer syntax: string tokens no longer admit escaped white space,
  2800 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2801 white space without escapes.
  2802 
  2803 * Outer syntax: string tokens may contain arbitrary character codes
  2804 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2805 "foo_bar".
  2806 
  2807 
  2808 *** Pure ***
  2809 
  2810 * Context-dependent token translations.  Default setup reverts locally
  2811 fixed variables, and adds hilite markup for undeclared frees.
  2812 
  2813 * Unused theorems can be found using the new command 'unused_thms'.
  2814 There are three ways of invoking it:
  2815 
  2816 (1) unused_thms
  2817      Only finds unused theorems in the current theory.
  2818 
  2819 (2) unused_thms thy_1 ... thy_n -
  2820      Finds unused theorems in the current theory and all of its ancestors,
  2821      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2822 
  2823 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2824      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2825      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2826      their ancestors.
  2827 
  2828 In order to increase the readability of the list produced by
  2829 unused_thms, theorems that have been created by a particular instance
  2830 of a theory command such as 'inductive' or 'function' are considered
  2831 to belong to the same "group", meaning that if at least one theorem in
  2832 this group is used, the other theorems in the same group are no longer
  2833 reported as unused.  Moreover, if all theorems in the group are
  2834 unused, only one theorem in the group is displayed.
  2835 
  2836 Note that proof objects have to be switched on in order for
  2837 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2838 usually the case when using Proof General with the default settings).
  2839 
  2840 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2841 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2842 duplicate fact bindings, or even accidental fact duplications.  Note
  2843 that tools may maintain dynamically scoped facts systematically, using
  2844 PureThy.add_thms_dynamic.
  2845 
  2846 * Command 'hide' now allows to hide from "fact" name space as well.
  2847 
  2848 * Eliminated destructive theorem database, simpset, claset, and
  2849 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2850 update of theories within ML code.
  2851 
  2852 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2853 INCOMPATIBILITY, object-logics depending on former Pure require
  2854 additional setup PureThy.old_appl_syntax_setup; object-logics
  2855 depending on former CPure need to refer to Pure.
  2856 
  2857 * Commands 'use' and 'ML' are now purely functional, operating on
  2858 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2859 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2860 INCOMPATIBILITY.
  2861 
  2862 * Command 'setup': discontinued implicit version with ML reference.
  2863 
  2864 * Instantiation target allows for simultaneous specification of class
  2865 instance operations together with an instantiation proof.
  2866 Type-checking phase allows to refer to class operations uniformly.
  2867 See src/HOL/Complex/Complex.thy for an Isar example and
  2868 src/HOL/Library/Eval.thy for an ML example.
  2869 
  2870 * Indexing of literal facts: be more serious about including only
  2871 facts from the visible specification/proof context, but not the
  2872 background context (locale etc.).  Affects `prop` notation and method
  2873 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2874 situations.
  2875 
  2876 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2877 "(open)" option, which used to expose internal bound variables to the
  2878 proof text.
  2879 
  2880 * Isar statements: removed obsolete case "rule_context".
  2881 INCOMPATIBILITY, better use explicit fixes/assumes.
  2882 
  2883 * Locale proofs: default proof step now includes 'unfold_locales';
  2884 hence 'proof' without argument may be used to unfold locale
  2885 predicates.
  2886 
  2887 
  2888 *** Document preparation ***
  2889 
  2890 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2891 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2892 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2893 spot); renamed link color from "darkblue" to "linkcolor" (default
  2894 value unchanged, can be redefined via \definecolor); no longer sets
  2895 "a4paper" option (unnecessary or even intrusive).
  2896 
  2897 * Antiquotation @{lemma A method} proves proposition A by the given
  2898 method (either a method name or a method name plus (optional) method
  2899 arguments in parentheses) and prints A just like @{prop A}.
  2900 
  2901 
  2902 *** HOL ***
  2903 
  2904 * New primrec package.  Specification syntax conforms in style to
  2905 definition/function/....  No separate induction rule is provided.  The
  2906 "primrec" command distinguishes old-style and new-style specifications
  2907 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2908 When adjusting theories, beware: constants stemming from new-style
  2909 primrec specifications have authentic syntax.
  2910 
  2911 * Metis prover is now an order of magnitude faster, and also works
  2912 with multithreading.
  2913 
  2914 * Metis: the maximum number of clauses that can be produced from a
  2915 theorem is now given by the attribute max_clauses.  Theorems that
  2916 exceed this number are ignored, with a warning printed.
  2917 
  2918 * Sledgehammer no longer produces structured proofs by default. To
  2919 enable, declare [[sledgehammer_full = true]].  Attributes
  2920 reconstruction_modulus, reconstruction_sorts renamed
  2921 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2922 
  2923 * Method "induct_scheme" derives user-specified induction rules
  2924 from well-founded induction and completeness of patterns. This factors
  2925 out some operations that are done internally by the function package
  2926 and makes them available separately.  See
  2927 src/HOL/ex/Induction_Scheme.thy for examples.
  2928 
  2929 * More flexible generation of measure functions for termination
  2930 proofs: Measure functions can be declared by proving a rule of the
  2931 form "is_measure f" and giving it the [measure_function] attribute.
  2932 The "is_measure" predicate is logically meaningless (always true), and
  2933 just guides the heuristic.  To find suitable measure functions, the
  2934 termination prover sets up the goal "is_measure ?f" of the appropriate
  2935 type and generates all solutions by prolog-style backwards proof using
  2936 the declared rules.
  2937 
  2938 This setup also deals with rules like 
  2939 
  2940   "is_measure f ==> is_measure (list_size f)"
  2941 
  2942 which accommodates nested datatypes that recurse through lists.
  2943 Similar rules are predeclared for products and option types.
  2944 
  2945 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  2946 
  2947   INCOMPATIBILITIES:
  2948 
  2949   - Definitions of overloaded constants on sets have to be replaced by
  2950     definitions on => and bool.
  2951 
  2952   - Some definitions of overloaded operators on sets can now be proved
  2953     using the definitions of the operators on => and bool.  Therefore,
  2954     the following theorems have been renamed:
  2955 
  2956       subset_def   -> subset_eq
  2957       psubset_def  -> psubset_eq
  2958       set_diff_def -> set_diff_eq
  2959       Compl_def    -> Compl_eq
  2960       Sup_set_def  -> Sup_set_eq
  2961       Inf_set_def  -> Inf_set_eq
  2962       sup_set_def  -> sup_set_eq
  2963       inf_set_def  -> inf_set_eq
  2964 
  2965   - Due to the incompleteness of the HO unification algorithm, some
  2966     rules such as subst may require manual instantiation, if some of
  2967     the unknowns in the rule is a set.
  2968 
  2969   - Higher order unification and forward proofs:
  2970     The proof pattern
  2971 
  2972       have "P (S::'a set)" <...>
  2973       then have "EX S. P S" ..
  2974 
  2975     no longer works (due to the incompleteness of the HO unification
  2976     algorithm) and must be replaced by the pattern
  2977 
  2978       have "EX S. P S"
  2979       proof
  2980         show "P S" <...>
  2981       qed
  2982 
  2983   - Calculational reasoning with subst (or similar rules):
  2984     The proof pattern
  2985 
  2986       have "P (S::'a set)" <...>
  2987       also have "S = T" <...>
  2988       finally have "P T" .
  2989 
  2990     no longer works (for similar reasons as the previous example) and
  2991     must be replaced by something like
  2992 
  2993       have "P (S::'a set)" <...>
  2994       moreover have "S = T" <...>
  2995       ultimately have "P T" by simp
  2996 
  2997   - Tactics or packages written in ML code:
  2998     Code performing pattern matching on types via
  2999 
  3000       Type ("set", [T]) => ...
  3001 
  3002     must be rewritten. Moreover, functions like strip_type or
  3003     binder_types no longer return the right value when applied to a
  3004     type of the form
  3005 
  3006       T1 => ... => Tn => U => bool
  3007 
  3008     rather than
  3009 
  3010       T1 => ... => Tn => U set
  3011 
  3012 * Merged theories Wellfounded_Recursion, Accessible_Part and
  3013 Wellfounded_Relations to theory Wellfounded.
  3014 
  3015 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  3016 
  3017 * Class finite no longer treats UNIV as class parameter.  Use class
  3018 enum from theory Library/Enum instead to achieve a similar effect.
  3019 INCOMPATIBILITY.
  3020 
  3021 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  3022 and "Cons".  INCOMPATIBILITY.
  3023 
  3024 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  3025 Potential INCOMPATIBILITY.
  3026 
  3027 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  3028 injective_fst_snd removed, use split_eta and prod_eqI instead.
  3029 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  3030 
  3031 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  3032 the same name in theory Orderings:
  3033 
  3034   less_trans
  3035   less_linear
  3036   le_imp_less_or_eq
  3037   le_less_trans
  3038   less_le_trans
  3039   less_not_sym
  3040   less_asym
  3041 
  3042 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  3043 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  3044 and different variable names.
  3045 
  3046 * Library/Option_ord.thy: Canonical order on option type.
  3047 
  3048 * Library/RBT.thy: Red-black trees, an efficient implementation of
  3049 finite maps.
  3050 
  3051 * Library/Countable.thy: Type class for countable types.
  3052 
  3053 * Theory Int: The representation of numerals has changed.  The infix
  3054 operator BIT and the bit datatype with constructors B0 and B1 have
  3055 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  3056 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  3057 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  3058 accordingly.
  3059 
  3060 * Theory Nat: definition of <= and < on natural numbers no longer
  3061 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  3062 le_def and less_def have disappeared.  Consider lemmas not_less
  3063 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  3064 
  3065 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  3066 (whose purpose mainly is for various fold_set functionals) have been
  3067 abandoned in favor of the existing algebraic classes
  3068 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  3069 lower_semilattice (resp. upper_semilattice) and linorder.
  3070 INCOMPATIBILITY.
  3071 
  3072 * Theory Transitive_Closure: induct and cases rules now declare proper
  3073 case_names ("base" and "step").  INCOMPATIBILITY.
  3074 
  3075 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  3076 lattices.  The form set-specific version is available as
  3077 Inductive.lfp_ordinal_induct_set.
  3078 
  3079 * Renamed theorems "power.simps" to "power_int.simps".
  3080 INCOMPATIBILITY.
  3081 
  3082 * Class semiring_div provides basic abstract properties of semirings
  3083 with division and modulo operations.  Subsumes former class dvd_mod.
  3084 
  3085 * Merged theories IntDef, Numeral and IntArith into unified theory
  3086 Int.  INCOMPATIBILITY.
  3087 
  3088 * Theory Library/Code_Index: type "index" now represents natural
  3089 numbers rather than integers.  INCOMPATIBILITY.
  3090 
  3091 * New class "uminus" with operation "uminus" (split of from class
  3092 "minus" which now only has operation "minus", binary).
  3093 INCOMPATIBILITY.
  3094 
  3095 * Constants "card", "internal_split", "option_map" now with authentic
  3096 syntax.  INCOMPATIBILITY.
  3097 
  3098 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  3099 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  3100 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  3101 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  3102 Sup_set_def, le_def, less_def, option_map_def now with object
  3103 equality.  INCOMPATIBILITY.
  3104 
  3105 * Records. Removed K_record, and replaced it by pure lambda term
  3106 %x. c. The simplifier setup is now more robust against eta expansion.
  3107 INCOMPATIBILITY: in cases explicitly referring to K_record.
  3108 
  3109 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  3110 
  3111 * Library/ListVector: new theory of arithmetic vector operations.
  3112 
  3113 * Library/Order_Relation: new theory of various orderings as sets of
  3114 pairs.  Defines preorders, partial orders, linear orders and
  3115 well-orders on sets and on types.
  3116 
  3117 
  3118 *** ZF ***
  3119 
  3120 * Renamed some theories to allow to loading both ZF and HOL in the
  3121 same session:
  3122 
  3123   Datatype  -> Datatype_ZF
  3124   Inductive -> Inductive_ZF
  3125   Int       -> Int_ZF
  3126   IntDiv    -> IntDiv_ZF
  3127   Nat       -> Nat_ZF
  3128   List      -> List_ZF
  3129   Main      -> Main_ZF
  3130 
  3131 INCOMPATIBILITY: ZF theories that import individual theories below
  3132 Main might need to be adapted.  Regular theory Main is still
  3133 available, as trivial extension of Main_ZF.
  3134 
  3135 
  3136 *** ML ***
  3137 
  3138 * ML within Isar: antiquotation @{const name} or @{const
  3139 name(typargs)} produces statically-checked Const term.
  3140 
  3141 * Functor NamedThmsFun: data is available to the user as dynamic fact
  3142 (of the same name).  Removed obsolete print command.
  3143 
  3144 * Removed obsolete "use_legacy_bindings" function.
  3145 
  3146 * The ``print mode'' is now a thread-local value derived from a global
  3147 template (the former print_mode reference), thus access becomes
  3148 non-critical.  The global print_mode reference is for session
  3149 management only; user-code should use print_mode_value,
  3150 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  3151 
  3152 * Functions system/system_out provide a robust way to invoke external
  3153 shell commands, with propagation of interrupts (requires Poly/ML
  3154 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  3155 
  3156 
  3157 *** System ***
  3158 
  3159 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  3160 in accordance with Proof General 3.7, which prefers GNU emacs.
  3161 
  3162 * isatool tty runs Isabelle process with plain tty interaction;
  3163 optional line editor may be specified via ISABELLE_LINE_EDITOR
  3164 setting, the default settings attempt to locate "ledit" and "rlwrap".
  3165 
  3166 * isatool browser now works with Cygwin as well, using general
  3167 "javapath" function defined in Isabelle process environment.
  3168 
  3169 * YXML notation provides a simple and efficient alternative to
  3170 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  3171 isatool yxml as described in the Isabelle system manual.
  3172 
  3173 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  3174 provides general wrapper for managing an Isabelle process in a robust
  3175 fashion, with ``cooked'' output from stdin/stderr.
  3176 
  3177 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  3178 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  3179 
  3180 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  3181 way of changing the user's settings is via
  3182 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  3183 script.
  3184 
  3185 * Multithreading.max_threads := 0 refers to the number of actual CPU
  3186 cores of the underlying machine, which is a good starting point for
  3187 optimal performance tuning.  The corresponding usedir option -M allows
  3188 "max" as an alias for "0".  WARNING: does not work on certain versions
  3189 of Mac OS (with Poly/ML 5.1).
  3190 
  3191 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  3192 adverse effect of Isabelle flooding interactive front-ends (notably
  3193 ProofGeneral / XEmacs).
  3194 
  3195 
  3196 
  3197 New in Isabelle2007 (November 2007)
  3198 -----------------------------------
  3199 
  3200 *** General ***
  3201 
  3202 * More uniform information about legacy features, notably a
  3203 warning/error of "Legacy feature: ...", depending on the state of the
  3204 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  3205 legacy features will disappear eventually.
  3206 
  3207 * Theory syntax: the header format ``theory A = B + C:'' has been
  3208 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  3209 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  3210 
  3211 * Theory syntax: the old non-Isar theory file format has been
  3212 discontinued altogether.  Note that ML proof scripts may still be used
  3213 with Isar theories; migration is usually quite simple with the ML
  3214 function use_legacy_bindings.  INCOMPATIBILITY.
  3215 
  3216 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  3217 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  3218 quotes.
  3219 
  3220 * Theory loader: be more serious about observing the static theory
  3221 header specifications (including optional directories), but not the
  3222 accidental file locations of previously successful loads.  The strict
  3223 update policy of former update_thy is now already performed by
  3224 use_thy, so the former has been removed; use_thys updates several
  3225 theories simultaneously, just as 'imports' within a theory header
  3226 specification, but without merging the results.  Potential
  3227 INCOMPATIBILITY: may need to refine theory headers and commands
  3228 ROOT.ML which depend on load order.
  3229 
  3230 * Theory loader: optional support for content-based file
  3231 identification, instead of the traditional scheme of full physical
  3232 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  3233 (cf. the system manual).  The new scheme allows to work with
  3234 non-finished theories in persistent session images, such that source
  3235 files may be moved later on without requiring reloads.
  3236 
  3237 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3238 file (with the same base name as the theory) are considered a legacy
  3239 feature, which will disappear eventually. Even now, the theory loader
  3240 no longer maintains dependencies on such files.
  3241 
  3242 * Syntax: the scope for resolving ambiguities via type-inference is
  3243 now limited to individual terms, instead of whole simultaneous
  3244 specifications as before. This greatly reduces the complexity of the
  3245 syntax module and improves flexibility by separating parsing and
  3246 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  3247 'fixes' etc.) are required in rare situations.
  3248 
  3249 * Syntax: constants introduced by new-style packages ('definition',
  3250 'abbreviation' etc.) are passed through the syntax module in
  3251 ``authentic mode''. This means that associated mixfix annotations
  3252 really stick to such constants, independently of potential name space
  3253 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  3254 trees are represented slightly differently, may need to adapt syntax
  3255 translations accordingly. Use CONST marker in 'translations' and
  3256 @{const_syntax} antiquotation in 'parse_translation' etc.
  3257 
  3258 * Legacy goal package: reduced interface to the bare minimum required
  3259 to keep existing proof scripts running.  Most other user-level
  3260 functions are now part of the OldGoals structure, which is *not* open
  3261 by default (consider isatool expandshort before open OldGoals).
  3262 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  3263 these tend to cause confusion about the actual goal (!) context being
  3264 used here, which is not necessarily the same as the_context().
  3265 
  3266 * Command 'find_theorems': supports "*" wild-card in "name:"
  3267 criterion; "with_dups" option.  Certain ProofGeneral versions might
  3268 support a specific search form (see ProofGeneral/CHANGES).
  3269 
  3270 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  3271 by default, which means that "prems" (and also "fixed variables") are
  3272 suppressed from proof state output.  Note that the ProofGeneral
  3273 settings mechanism allows to change and save options persistently, but
  3274 older versions of Isabelle will fail to start up if a negative prems
  3275 limit is imposed.
  3276 
  3277 * Local theory targets may be specified by non-nested blocks of
  3278 ``context/locale/class ... begin'' followed by ``end''.  The body may
  3279 contain definitions, theorems etc., including any derived mechanism
  3280 that has been implemented on top of these primitives.  This concept
  3281 generalizes the existing ``theorem (in ...)'' towards more versatility
  3282 and scalability.
  3283 
  3284 * Proof General interface: proper undo of final 'end' command;
  3285 discontinued Isabelle/classic mode (ML proof scripts).
  3286 
  3287 
  3288 *** Document preparation ***
  3289 
  3290 * Added antiquotation @{theory name} which prints the given name,
  3291 after checking that it refers to a valid ancestor theory in the
  3292 current context.
  3293 
  3294 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  3295 check the given source text as ML type/structure, printing verbatim.
  3296 
  3297 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  3298 "c args == rhs" given in the current context.  (Any number of
  3299 arguments may be given on the LHS.)
  3300 
  3301 
  3302 *** Pure ***
  3303 
  3304 * The 'class' package offers a combination of axclass and locale to
  3305 achieve Haskell-like type classes in Isabelle.  Definitions and
  3306 theorems within a class context produce both relative results (with
  3307 implicit parameters according to the locale context), and polymorphic
  3308 constants with qualified polymorphism (according to the class
  3309 context).  Within the body context of a 'class' target, a separate
  3310 syntax layer ("user space type system") takes care of converting
  3311 between global polymorphic consts and internal locale representation.
  3312 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  3313 "isatool doc classes" provides a tutorial.
  3314 
  3315 * Generic code generator framework allows to generate executable
  3316 code for ML and Haskell (including Isabelle classes).  A short usage
  3317 sketch:
  3318 
  3319     internal compilation:
  3320         export_code <list of constants (term syntax)> in SML
  3321     writing SML code to a file:
  3322         export_code <list of constants (term syntax)> in SML <filename>
  3323     writing OCaml code to a file:
  3324         export_code <list of constants (term syntax)> in OCaml <filename>
  3325     writing Haskell code to a bunch of files:
  3326         export_code <list of constants (term syntax)> in Haskell <filename>
  3327 
  3328     evaluating closed propositions to True/False using code generation:
  3329         method ``eval''
  3330 
  3331 Reasonable default setup of framework in HOL.
  3332 
  3333 Theorem attributs for selecting and transforming function equations theorems:
  3334 
  3335     [code fun]:        select a theorem as function equation for a specific constant
  3336     [code fun del]:    deselect a theorem as function equation for a specific constant
  3337     [code inline]:     select an equation theorem for unfolding (inlining) in place
  3338     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  3339 
  3340 User-defined serializations (target in {SML, OCaml, Haskell}):
  3341 
  3342     code_const <and-list of constants (term syntax)>
  3343       {(target) <and-list of const target syntax>}+
  3344 
  3345     code_type <and-list of type constructors>
  3346       {(target) <and-list of type target syntax>}+
  3347 
  3348     code_instance <and-list of instances>
  3349       {(target)}+
  3350         where instance ::= <type constructor> :: <class>
  3351 
  3352     code_class <and_list of classes>
  3353       {(target) <and-list of class target syntax>}+
  3354         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  3355 
  3356 code_instance and code_class only are effective to target Haskell.
  3357 
  3358 For example usage see src/HOL/ex/Codegenerator.thy and
  3359 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  3360 generation from Isabelle/HOL theories is available via "isatool doc
  3361 codegen".
  3362 
  3363 * Code generator: consts in 'consts_code' Isar commands are now
  3364 referred to by usual term syntax (including optional type
  3365 annotations).
  3366 
  3367 * Command 'no_translations' removes translation rules from theory
  3368 syntax.
  3369 
  3370 * Overloaded definitions are now actually checked for acyclic
  3371 dependencies.  The overloading scheme is slightly more general than
  3372 that of Haskell98, although Isabelle does not demand an exact
  3373 correspondence to type class and instance declarations.
  3374 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  3375 exotic versions of overloading -- at the discretion of the user!
  3376 
  3377 Polymorphic constants are represented via type arguments, i.e. the
  3378 instantiation that matches an instance against the most general
  3379 declaration given in the signature.  For example, with the declaration
  3380 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  3381 as c(nat).  Overloading is essentially simultaneous structural
  3382 recursion over such type arguments.  Incomplete specification patterns
  3383 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  3384 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  3385 Command 'print_theory' outputs the normalized system of recursive
  3386 equations, see section "definitions".
  3387 
  3388 * Configuration options are maintained within the theory or proof
  3389 context (with name and type bool/int/string), providing a very simple
  3390 interface to a poor-man's version of general context data.  Tools may
  3391 declare options in ML (e.g. using Attrib.config_int) and then refer to
  3392 these values using Config.get etc.  Users may change options via an
  3393 associated attribute of the same name.  This form of context
  3394 declaration works particularly well with commands 'declare' or
  3395 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  3396 very easy to avoid global references, which would not observe Isar
  3397 toplevel undo/redo and fail to work with multithreading.
  3398 
  3399 Various global ML references of Pure and HOL have been turned into
  3400 configuration options:
  3401 
  3402   Unify.search_bound		unify_search_bound
  3403   Unify.trace_bound		unify_trace_bound
  3404   Unify.trace_simp		unify_trace_simp
  3405   Unify.trace_types		unify_trace_types
  3406   Simplifier.simp_depth_limit	simp_depth_limit
  3407   Blast.depth_limit		blast_depth_limit
  3408   DatatypeProp.dtK		datatype_distinctness_limit
  3409   fast_arith_neq_limit  	fast_arith_neq_limit
  3410   fast_arith_split_limit	fast_arith_split_limit
  3411 
  3412 * Named collections of theorems may be easily installed as context
  3413 data using the functor NamedThmsFun (see also
  3414 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  3415 attributes; there is also a toplevel print command.  This facility is
  3416 just a common case of general context data, which is the preferred way
  3417 for anything more complex than just a list of facts in canonical
  3418 order.
  3419 
  3420 * Isar: command 'declaration' augments a local theory by generic
  3421 declaration functions written in ML.  This enables arbitrary content
  3422 being added to the context, depending on a morphism that tells the
  3423 difference of the original declaration context wrt. the application
  3424 context encountered later on.
  3425 
  3426 * Isar: proper interfaces for simplification procedures.  Command
  3427 'simproc_setup' declares named simprocs (with match patterns, and body
  3428 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  3429 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  3430 
  3431 * Isar: an extra pair of brackets around attribute declarations
  3432 abbreviates a theorem reference involving an internal dummy fact,
  3433 which will be ignored later --- only the effect of the attribute on
  3434 the background context will persist.  This form of in-place
  3435 declarations is particularly useful with commands like 'declare' and
  3436 'using', for example ``have A using [[simproc a]] by simp''.
  3437 
  3438 * Isar: method "assumption" (and implicit closing of subproofs) now
  3439 takes simple non-atomic goal assumptions into account: after applying
  3440 an assumption as a rule the resulting subgoals are solved by atomic
  3441 assumption steps.  This is particularly useful to finish 'obtain'
  3442 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  3443 without referring to the original premise "!!x. P x ==> thesis" in the
  3444 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  3445 more permissive.
  3446 
  3447 * Isar: implicit use of prems from the Isar proof context is
  3448 considered a legacy feature.  Common applications like ``have A .''
  3449 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  3450 referencing facts explicitly here improves readability and
  3451 maintainability of proof texts.
  3452 
  3453 * Isar: improper proof element 'guess' is like 'obtain', but derives
  3454 the obtained context from the course of reasoning!  For example:
  3455 
  3456   assume "EX x y. A x & B y"   -- "any previous fact"
  3457   then guess x and y by clarify
  3458 
  3459 This technique is potentially adventurous, depending on the facts and
  3460 proof tools being involved here.
  3461 
  3462 * Isar: known facts from the proof context may be specified as literal
  3463 propositions, using ASCII back-quote syntax.  This works wherever
  3464 named facts used to be allowed so far, in proof commands, proof
  3465 methods, attributes etc.  Literal facts are retrieved from the context
  3466 according to unification of type and term parameters.  For example,
  3467 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  3468 theorems in the current context, then these are valid literal facts:
  3469 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  3470 
  3471 There is also a proof method "fact" which does the same composition
  3472 for explicit goal states, e.g. the following proof texts coincide with
  3473 certain special cases of literal facts:
  3474 
  3475   have "A" by fact                 ==  note `A`
  3476   have "A ==> B" by fact           ==  note `A ==> B`
  3477   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  3478   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  3479 
  3480 * Isar: ":" (colon) is no longer a symbolic identifier character in
  3481 outer syntax.  Thus symbolic identifiers may be used without
  3482 additional white space in declarations like this: ``assume *: A''.
  3483 
  3484 * Isar: 'print_facts' prints all local facts of the current context,
  3485 both named and unnamed ones.
  3486 
  3487 * Isar: 'def' now admits simultaneous definitions, e.g.:
  3488 
  3489   def x == "t" and y == "u"
  3490 
  3491 * Isar: added command 'unfolding', which is structurally similar to
  3492 'using', but affects both the goal state and facts by unfolding given
  3493 rewrite rules.  Thus many occurrences of the 'unfold' method or
  3494 'unfolded' attribute may be replaced by first-class proof text.
  3495 
  3496 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  3497 and command 'unfolding' now all support object-level equalities
  3498 (potentially conditional).  The underlying notion of rewrite rule is
  3499 analogous to the 'rule_format' attribute, but *not* that of the
  3500 Simplifier (which is usually more generous).
  3501 
  3502 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  3503 premises of a theorem by n. Useful in conjunction with drule.
  3504 
  3505 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  3506 method expression within a sandbox consisting of the first N
  3507 sub-goals, which need to exist.  For example, ``simp_all [3]''
  3508 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  3509 simplifies all new goals that emerge from applying rule foo to the
  3510 originally first one.
  3511 
  3512 * Isar: schematic goals are no longer restricted to higher-order
  3513 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  3514 expected.
  3515 
  3516 * Isar: the conclusion of a long theorem statement is now either
  3517 'shows' (a simultaneous conjunction, as before), or 'obtains'
  3518 (essentially a disjunction of cases with local parameters and
  3519 assumptions).  The latter allows to express general elimination rules
  3520 adequately; in this notation common elimination rules look like this:
  3521 
  3522   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  3523     assumes "EX x. P x"
  3524     obtains x where "P x"
  3525 
  3526   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  3527     assumes "A & B"
  3528     obtains A and B
  3529 
  3530   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  3531     assumes "A | B"
  3532     obtains
  3533       A
  3534     | B
  3535 
  3536 The subsequent classical rules even refer to the formal "thesis"
  3537 explicitly:
  3538 
  3539   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  3540     obtains "~ thesis"
  3541 
  3542   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  3543     obtains "thesis ==> something"
  3544 
  3545 The actual proof of an 'obtains' statement is analogous to that of the
  3546 Isar proof element 'obtain', only that there may be several cases.
  3547 Optional case names may be specified in parentheses; these will be
  3548 available both in the present proof and as annotations in the
  3549 resulting rule, for later use with the 'cases' method (cf. attribute
  3550 case_names).
  3551 
  3552 * Isar: the assumptions of a long theorem statement are available as
  3553 "assms" fact in the proof context.  This is more appropriate than the
  3554 (historical) "prems", which refers to all assumptions of the current
  3555 context, including those from the target locale, proof body etc.
  3556 
  3557 * Isar: 'print_statement' prints theorems from the current theory or
  3558 proof context in long statement form, according to the syntax of a
  3559 top-level lemma.
  3560 
  3561 * Isar: 'obtain' takes an optional case name for the local context
  3562 introduction rule (default "that").
  3563 
  3564 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  3565 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  3566 to occur.
  3567 
  3568 * Pure: syntax "CONST name" produces a fully internalized constant
  3569 according to the current context.  This is particularly useful for
  3570 syntax translations that should refer to internal constant
  3571 representations independently of name spaces.
  3572 
  3573 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  3574 instead of "FOO ". This allows multiple binder declarations to coexist
  3575 in the same context.  INCOMPATIBILITY.
  3576 
  3577 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  3578 primitive that also works in a locale context (both for constants and
  3579 fixed variables). Type declaration and internal syntactic representation
  3580 of given constants retrieved from the context. Likewise, the
  3581 'no_notation' command allows to remove given syntax annotations from the
  3582 current context.
  3583 
  3584 * Isar/locales: new derived specification elements 'axiomatization',
  3585 'definition', 'abbreviation', which support type-inference, admit
  3586 object-level specifications (equality, equivalence).  See also the
  3587 isar-ref manual.  Examples:
  3588 
  3589   axiomatization
  3590     eq  (infix "===" 50) where
  3591     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  3592 
  3593   definition "f x y = x + y + 1"
  3594   definition g where "g x = f x x"
  3595 
  3596   abbreviation
  3597     neq  (infix "=!=" 50) where
  3598     "x =!= y == ~ (x === y)"
  3599 
  3600 These specifications may be also used in a locale context.  Then the
  3601 constants being introduced depend on certain fixed parameters, and the
  3602 constant name is qualified by the locale base name.  An internal
  3603 abbreviation takes care for convenient input and output, making the
  3604 parameters implicit and using the original short name.  See also
  3605 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  3606 entities from a monomorphic theory.
  3607 
  3608 Presently, abbreviations are only available 'in' a target locale, but
  3609 not inherited by general import expressions.  Also note that
  3610 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  3611 'translations' in common applications.  The "no_abbrevs" print mode
  3612 prevents folding of abbreviations in term output.
  3613 
  3614 Concrete syntax is attached to specified constants in internal form,
  3615 independently of name spaces.  The parse tree representation is
  3616 slightly different -- use 'notation' instead of raw 'syntax', and
  3617 'translations' with explicit "CONST" markup to accommodate this.
  3618 
  3619 * Pure/Isar: unified syntax for new-style specification mechanisms
  3620 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  3621 full type inference and dummy patterns ("_").  For example:
  3622 
  3623   definition "K x _ = x"
  3624 
  3625   inductive conj for A B
  3626   where "A ==> B ==> conj A B"
  3627 
  3628 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  3629 the current context.  Print mode "no_abbrevs" prevents inversion of
  3630 abbreviations on output.
  3631 
  3632 * Isar/locales: improved parameter handling: use of locales "var" and
  3633 "struct" no longer necessary; - parameter renamings are no longer
  3634 required to be injective.  For example, this allows to define
  3635 endomorphisms as locale endom = homom mult mult h.
  3636 
  3637 * Isar/locales: changed the way locales with predicates are defined.
  3638 Instead of accumulating the specification, the imported expression is
  3639 now an interpretation.  INCOMPATIBILITY: different normal form of
  3640 locale expressions.  In particular, in interpretations of locales with
  3641 predicates, goals repesenting already interpreted fragments are not
  3642 removed automatically.  Use methods `intro_locales' and
  3643 `unfold_locales'; see below.
  3644 
  3645 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  3646 provide backward reasoning on locales predicates.  The methods are
  3647 aware of interpretations and discharge corresponding goals.
  3648 `intro_locales' is less aggressive then `unfold_locales' and does not
  3649 unfold predicates to assumptions.
  3650 
  3651 * Isar/locales: the order in which locale fragments are accumulated
  3652 has changed.  This enables to override declarations from fragments due
  3653 to interpretations -- for example, unwanted simp rules.
  3654 
  3655 * Isar/locales: interpretation in theories and proof contexts has been
  3656 extended.  One may now specify (and prove) equations, which are
  3657 unfolded in interpreted theorems.  This is useful for replacing
  3658 defined concepts (constants depending on locale parameters) by
  3659 concepts already existing in the target context.  Example:
  3660 
  3661   interpretation partial_order ["op <= :: [int, int] => bool"]
  3662     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3663 
  3664 Typically, the constant `partial_order.less' is created by a
  3665 definition specification element in the context of locale
  3666 partial_order.
  3667 
  3668 * Method "induct": improved internal context management to support
  3669 local fixes and defines on-the-fly. Thus explicit meta-level
  3670 connectives !!  and ==> are rarely required anymore in inductive goals
  3671 (using object-logic connectives for this purpose has been long
  3672 obsolete anyway). Common proof patterns are explained in
  3673 src/HOL/Induct/Common_Patterns.thy, see also
  3674 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3675 examples.
  3676 
  3677 * Method "induct": improved handling of simultaneous goals. Instead of
  3678 introducing object-level conjunction, the statement is now split into
  3679 several conclusions, while the corresponding symbolic cases are nested
  3680 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3681 see src/HOL/Induct/Common_Patterns.thy, for example.
  3682 
  3683 * Method "induct": mutual induction rules are now specified as a list
  3684 of rule sharing the same induction cases. HOL packages usually provide
  3685 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3686 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3687 mutual induction rules differently, i.e. like this:
  3688 
  3689   (induct rule: foo_bar.inducts)
  3690   (induct set: foo bar)
  3691   (induct pred: foo bar)
  3692   (induct type: foo bar)
  3693 
  3694 The ML function ProjectRule.projections turns old-style rules into the
  3695 new format.
  3696 
  3697 * Method "coinduct": dual of induction, see
  3698 src/HOL/Library/Coinductive_List.thy for various examples.
  3699 
  3700 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3701 considered a legacy feature.
  3702 
  3703 * Attribute "symmetric" produces result with standardized schematic
  3704 variables (index 0).  Potential INCOMPATIBILITY.
  3705 
  3706 * Simplifier: by default the simplifier trace only shows top level
  3707 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3708 default. Thus there is less danger of being flooded by the trace. The
  3709 trace indicates where parts have been suppressed.
  3710   
  3711 * Provers/classical: removed obsolete classical version of elim_format
  3712 attribute; classical elim/dest rules are now treated uniformly when
  3713 manipulating the claset.
  3714 
  3715 * Provers/classical: stricter checks to ensure that supplied intro,
  3716 dest and elim rules are well-formed; dest and elim rules must have at
  3717 least one premise.
  3718 
  3719 * Provers/classical: attributes dest/elim/intro take an optional
  3720 weight argument for the rule (just as the Pure versions).  Weights are
  3721 ignored by automated tools, but determine the search order of single
  3722 rule steps.
  3723 
  3724 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3725 where the body does not mention the bound variable.  Note that dummy
  3726 patterns implicitly depend on their context of bounds, which makes
  3727 "{_. _}" match any set comprehension as expected.  Potential
  3728 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3729 constant "_idtdummy" in the binding position.
  3730 
  3731 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3732 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3733 for example "A -> B" => "Pi A (%_. B)".
  3734 
  3735 * Pure: 'class_deps' command visualizes the subclass relation, using
  3736 the graph browser tool.
  3737 
  3738 * Pure: 'print_theory' now suppresses certain internal declarations by
  3739 default; use '!' option for full details.
  3740 
  3741 
  3742 *** HOL ***
  3743 
  3744 * Method "metis" proves goals by applying the Metis general-purpose
  3745 resolution prover (see also http://gilith.com/software/metis/).
  3746 Examples are in the directory MetisExamples.  WARNING: the
  3747 Isabelle/HOL-Metis integration does not yet work properly with
  3748 multi-threading.
  3749   
  3750 * Command 'sledgehammer' invokes external automatic theorem provers as
  3751 background processes.  It generates calls to the "metis" method if
  3752 successful. These can be pasted into the proof.  Users do not have to
  3753 wait for the automatic provers to return.  WARNING: does not really
  3754 work with multi-threading.
  3755 
  3756 * New "auto_quickcheck" feature tests outermost goal statements for
  3757 potential counter-examples.  Controlled by ML references
  3758 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3759 5000 milliseconds).  Fails silently if statements is outside of
  3760 executable fragment, or any other codgenerator problem occurs.
  3761 
  3762 * New constant "undefined" with axiom "undefined x = undefined".
  3763 
  3764 * Added class "HOL.eq", allowing for code generation with polymorphic
  3765 equality.
  3766 
  3767 * Some renaming of class constants due to canonical name prefixing in
  3768 the new 'class' package:
  3769 
  3770     HOL.abs ~> HOL.abs_class.abs
  3771     HOL.divide ~> HOL.divide_class.divide
  3772     0 ~> HOL.zero_class.zero
  3773     1 ~> HOL.one_class.one
  3774     op + ~> HOL.plus_class.plus
  3775     op - ~> HOL.minus_class.minus
  3776     uminus ~> HOL.minus_class.uminus
  3777     op * ~> HOL.times_class.times
  3778     op < ~> HOL.ord_class.less
  3779     op <= > HOL.ord_class.less_eq
  3780     Nat.power ~> Power.power_class.power
  3781     Nat.size ~> Nat.size_class.size
  3782     Numeral.number_of ~> Numeral.number_class.number_of
  3783     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3784     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3785     Orderings.min ~> Orderings.ord_class.min
  3786     Orderings.max ~> Orderings.ord_class.max
  3787     Divides.op div ~> Divides.div_class.div
  3788     Divides.op mod ~> Divides.div_class.mod
  3789     Divides.op dvd ~> Divides.div_class.dvd
  3790 
  3791 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3792 
  3793 a) User-defined constants using any of the names "plus", "minus",
  3794 "times", "less" or "less_eq". The standard syntax translations for
  3795 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3796 names.
  3797 
  3798 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3799 INCOMPATIBILITY: use more specific names.
  3800 
  3801 c) Permutative equations (e.g. "a + b = b + a")
  3802 Since the change of names also changes the order of terms, permutative
  3803 rewrite rules may get applied in a different order. Experience shows
  3804 that this is rarely the case (only two adaptions in the whole Isabelle
  3805 distribution).  INCOMPATIBILITY: rewrite proofs
  3806 
  3807 d) ML code directly refering to constant names
  3808 This in general only affects hand-written proof tactics, simprocs and
  3809 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3810 Consider using @{const_name} antiquotation.
  3811 
  3812 * New class "default" with associated constant "default".
  3813 
  3814 * Function "sgn" is now overloaded and available on int, real, complex
  3815 (and other numeric types), using class "sgn".  Two possible defs of
  3816 sgn are given as equational assumptions in the classes sgn_if and
  3817 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3818 INCOMPATIBILITY.
  3819 
  3820 * Locale "partial_order" now unified with class "order" (cf. theory
  3821 Orderings), added parameter "less".  INCOMPATIBILITY.
  3822 
  3823 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3824 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3825 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3826 
  3827 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3828 changed order of proof goals in instance proofs.
  3829 
  3830 * The transitivity reasoner for partial and linear orders is set up
  3831 for classes "order" and "linorder".  Instances of the reasoner are available
  3832 in all contexts importing or interpreting the corresponding locales.
  3833 Method "order" invokes the reasoner separately; the reasoner
  3834 is also integrated with the Simplifier as a solver.  Diagnostic
  3835 command 'print_orders' shows the available instances of the reasoner
  3836 in the current context.
  3837 
  3838 * Localized monotonicity predicate in theory "Orderings"; integrated
  3839 lemmas max_of_mono and min_of_mono with this predicate.
  3840 INCOMPATIBILITY.
  3841 
  3842 * Formulation of theorem "dense" changed slightly due to integration
  3843 with new class dense_linear_order.
  3844 
  3845 * Uniform lattice theory development in HOL.
  3846 
  3847     constants "meet" and "join" now named "inf" and "sup"
  3848     constant "Meet" now named "Inf"
  3849 
  3850     classes "meet_semilorder" and "join_semilorder" now named
  3851       "lower_semilattice" and "upper_semilattice"
  3852     class "lorder" now named "lattice"
  3853     class "comp_lat" now named "complete_lattice"
  3854 
  3855     Instantiation of lattice classes allows explicit definitions
  3856     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3857 
  3858   INCOMPATIBILITY.  Theorem renames:
  3859 
  3860     meet_left_le            ~> inf_le1
  3861     meet_right_le           ~> inf_le2
  3862     join_left_le            ~> sup_ge1
  3863     join_right_le           ~> sup_ge2
  3864     meet_join_le            ~> inf_sup_ord
  3865     le_meetI                ~> le_infI
  3866     join_leI                ~> le_supI
  3867     le_meet                 ~> le_inf_iff
  3868     le_join                 ~> ge_sup_conv
  3869     meet_idempotent         ~> inf_idem
  3870     join_idempotent         ~> sup_idem
  3871     meet_comm               ~> inf_commute
  3872     join_comm               ~> sup_commute
  3873     meet_leI1               ~> le_infI1
  3874     meet_leI2               ~> le_infI2
  3875     le_joinI1               ~> le_supI1
  3876     le_joinI2               ~> le_supI2
  3877     meet_assoc              ~> inf_assoc
  3878     join_assoc              ~> sup_assoc
  3879     meet_left_comm          ~> inf_left_commute
  3880     meet_left_idempotent    ~> inf_left_idem
  3881     join_left_comm          ~> sup_left_commute
  3882     join_left_idempotent    ~> sup_left_idem
  3883     meet_aci                ~> inf_aci
  3884     join_aci                ~> sup_aci
  3885     le_def_meet             ~> le_iff_inf
  3886     le_def_join             ~> le_iff_sup
  3887     join_absorp2            ~> sup_absorb2
  3888     join_absorp1            ~> sup_absorb1
  3889     meet_absorp1            ~> inf_absorb1
  3890     meet_absorp2            ~> inf_absorb2
  3891     meet_join_absorp        ~> inf_sup_absorb
  3892     join_meet_absorp        ~> sup_inf_absorb
  3893     distrib_join_le         ~> distrib_sup_le
  3894     distrib_meet_le         ~> distrib_inf_le
  3895 
  3896     add_meet_distrib_left   ~> add_inf_distrib_left
  3897     add_join_distrib_left   ~> add_sup_distrib_left
  3898     is_join_neg_meet        ~> is_join_neg_inf
  3899     is_meet_neg_join        ~> is_meet_neg_sup
  3900     add_meet_distrib_right  ~> add_inf_distrib_right
  3901     add_join_distrib_right  ~> add_sup_distrib_right
  3902     add_meet_join_distribs  ~> add_sup_inf_distribs
  3903     join_eq_neg_meet        ~> sup_eq_neg_inf
  3904     meet_eq_neg_join        ~> inf_eq_neg_sup
  3905     add_eq_meet_join        ~> add_eq_inf_sup
  3906     meet_0_imp_0            ~> inf_0_imp_0
  3907     join_0_imp_0            ~> sup_0_imp_0
  3908     meet_0_eq_0             ~> inf_0_eq_0
  3909     join_0_eq_0             ~> sup_0_eq_0
  3910     neg_meet_eq_join        ~> neg_inf_eq_sup
  3911     neg_join_eq_meet        ~> neg_sup_eq_inf
  3912     join_eq_if              ~> sup_eq_if
  3913 
  3914     mono_meet               ~> mono_inf
  3915     mono_join               ~> mono_sup
  3916     meet_bool_eq            ~> inf_bool_eq
  3917     join_bool_eq            ~> sup_bool_eq
  3918     meet_fun_eq             ~> inf_fun_eq
  3919     join_fun_eq             ~> sup_fun_eq
  3920     meet_set_eq             ~> inf_set_eq
  3921     join_set_eq             ~> sup_set_eq
  3922     meet1_iff               ~> inf1_iff
  3923     meet2_iff               ~> inf2_iff
  3924     meet1I                  ~> inf1I
  3925     meet2I                  ~> inf2I
  3926     meet1D1                 ~> inf1D1
  3927     meet2D1                 ~> inf2D1
  3928     meet1D2                 ~> inf1D2
  3929     meet2D2                 ~> inf2D2
  3930     meet1E                  ~> inf1E
  3931     meet2E                  ~> inf2E
  3932     join1_iff               ~> sup1_iff
  3933     join2_iff               ~> sup2_iff
  3934     join1I1                 ~> sup1I1
  3935     join2I1                 ~> sup2I1
  3936     join1I1                 ~> sup1I1
  3937     join2I2                 ~> sup1I2
  3938     join1CI                 ~> sup1CI
  3939     join2CI                 ~> sup2CI
  3940     join1E                  ~> sup1E
  3941     join2E                  ~> sup2E
  3942 
  3943     is_meet_Meet            ~> is_meet_Inf
  3944     Meet_bool_def           ~> Inf_bool_def
  3945     Meet_fun_def            ~> Inf_fun_def
  3946     Meet_greatest           ~> Inf_greatest
  3947     Meet_lower              ~> Inf_lower
  3948     Meet_set_def            ~> Inf_set_def
  3949 
  3950     Sup_def                 ~> Sup_Inf
  3951     Sup_bool_eq             ~> Sup_bool_def
  3952     Sup_fun_eq              ~> Sup_fun_def
  3953     Sup_set_eq              ~> Sup_set_def
  3954 
  3955     listsp_meetI            ~> listsp_infI
  3956     listsp_meet_eq          ~> listsp_inf_eq
  3957 
  3958     meet_min                ~> inf_min
  3959     join_max                ~> sup_max
  3960 
  3961 * Added syntactic class "size"; overloaded constant "size" now has
  3962 type "'a::size ==> bool"
  3963 
  3964 * Internal reorganisation of `size' of datatypes: size theorems
  3965 "foo.size" are no longer subsumed by "foo.simps" (but are still
  3966 simplification rules by default!); theorems "prod.size" now named
  3967 "*.size".
  3968 
  3969 * Class "div" now inherits from class "times" rather than "type".
  3970 INCOMPATIBILITY.
  3971 
  3972 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  3973 Linorder etc.  have disappeared; operations defined in terms of
  3974 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  3975 
  3976 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  3977 
  3978 * HOL-Word: New extensive library and type for generic, fixed size
  3979 machine words, with arithemtic, bit-wise, shifting and rotating
  3980 operations, reflection into int, nat, and bool lists, automation for
  3981 linear arithmetic (by automatic reflection into nat or int), including
  3982 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  3983 arithmetic type classes, supporting automatic simplification of
  3984 numerals on all operations.
  3985 
  3986 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  3987 
  3988 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  3989 
  3990 * Code generator library theories:
  3991   - Code_Integer represents HOL integers by big integer literals in target
  3992     languages.
  3993   - Code_Char represents HOL characters by character literals in target
  3994     languages.
  3995   - Code_Char_chr like Code_Char, but also offers treatment of character
  3996     codes; includes Code_Integer.
  3997   - Executable_Set allows to generate code for finite sets using lists.
  3998   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  3999     denominator).
  4000   - Executable_Real implements a subset of real numbers, namly those
  4001     representable by rational numbers.
  4002   - Efficient_Nat implements natural numbers by integers, which in general will
  4003     result in higher efficency; pattern matching with 0/Suc is eliminated;
  4004     includes Code_Integer.
  4005   - Code_Index provides an additional datatype index which is mapped to
  4006     target-language built-in integers.
  4007   - Code_Message provides an additional datatype message_string which is isomorphic to
  4008     strings; messages are mapped to target-language strings.
  4009 
  4010 * New package for inductive predicates
  4011 
  4012   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  4013 
  4014     inductive
  4015       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4016       for z_1 :: U_1 and ... and z_n :: U_m
  4017     where
  4018       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4019     | ...
  4020 
  4021   with full support for type-inference, rather than
  4022 
  4023     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4024 
  4025     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4026     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4027 
  4028     inductive "s z_1 ... z_m"
  4029     intros
  4030       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4031       ...
  4032 
  4033   For backward compatibility, there is a wrapper allowing inductive
  4034   sets to be defined with the new package via
  4035 
  4036     inductive_set
  4037       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4038       for z_1 :: U_1 and ... and z_n :: U_m
  4039     where
  4040       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4041     | ...
  4042 
  4043   or
  4044 
  4045     inductive_set
  4046       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4047       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4048       for z_1 :: U_1 and ... and z_n :: U_m
  4049     where
  4050       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4051     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4052     | ...
  4053 
  4054   if the additional syntax "p ..." is required.
  4055 
  4056   Numerous examples can be found in the subdirectories src/HOL/Auth,
  4057   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  4058 
  4059   INCOMPATIBILITIES:
  4060 
  4061   - Since declaration and definition of inductive sets or predicates
  4062     is no longer separated, abbreviations involving the newly
  4063     introduced sets or predicates must be specified together with the
  4064     introduction rules after the 'where' keyword (see above), rather
  4065     than before the actual inductive definition.
  4066 
  4067   - The variables in induction and elimination rules are now
  4068     quantified in the order of their occurrence in the introduction
  4069     rules, rather than in alphabetical order. Since this may break
  4070     some proofs, these proofs either have to be repaired, e.g. by
  4071     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  4072     statements of the form
  4073 
  4074       case (rule_i a_i_1 ... a_i_{k_i})
  4075 
  4076     or the old order of quantification has to be restored by explicitly adding
  4077     meta-level quantifiers in the introduction rules, i.e.
  4078 
  4079       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  4080 
  4081   - The format of the elimination rules is now
  4082 
  4083       p z_1 ... z_m x_1 ... x_n ==>
  4084         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4085         ==> ... ==> P
  4086 
  4087     for predicates and
  4088 
  4089       (x_1, ..., x_n) : s z_1 ... z_m ==>
  4090         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4091         ==> ... ==> P
  4092 
  4093     for sets rather than
  4094 
  4095       x : s z_1 ... z_m ==>
  4096         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  4097         ==> ... ==> P
  4098 
  4099     This may require terms in goals to be expanded to n-tuples
  4100     (e.g. using case_tac or simplification with the split_paired_all
  4101     rule) before the above elimination rule is applicable.
  4102 
  4103   - The elimination or case analysis rules for (mutually) inductive
  4104     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  4105     list of rules "p_1_..._p_k.elims" is no longer available.
  4106 
  4107 * New package "function"/"fun" for general recursive functions,
  4108 supporting mutual and nested recursion, definitions in local contexts,
  4109 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  4110 for small examples, and the separate tutorial on the function
  4111 package. The old recdef "package" is still available as before, but
  4112 users are encouraged to use the new package.
  4113 
  4114 * Method "lexicographic_order" automatically synthesizes termination
  4115 relations as lexicographic combinations of size measures. 
  4116 
  4117 * Case-expressions allow arbitrary constructor-patterns (including
  4118 "_") and take their order into account, like in functional
  4119 programming.  Internally, this is translated into nested
  4120 case-expressions; missing cases are added and mapped to the predefined
  4121 constant "undefined". In complicated cases printing may no longer show
  4122 the original input but the internal form. Lambda-abstractions allow
  4123 the same form of pattern matching: "% pat1 => e1 | ..." is an
  4124 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  4125 variable.
  4126 
  4127 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  4128 is an abbreviation for "of_nat :: nat => int". The simplification
  4129 rules for "of_nat" have been changed to work like "int" did
  4130 previously.  Potential INCOMPATIBILITY:
  4131   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  4132   - of_nat_diff and of_nat_mult are no longer default simp rules
  4133 
  4134 * Method "algebra" solves polynomial equations over (semi)rings using
  4135 Groebner bases. The (semi)ring structure is defined by locales and the
  4136 tool setup depends on that generic context. Installing the method for
  4137 a specific type involves instantiating the locale and possibly adding
  4138 declarations for computation on the coefficients.  The method is
  4139 already instantiated for natural numbers and for the axiomatic class
  4140 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  4141 CALCULEMUS 2007 for the general principles underlying this
  4142 architecture of context-aware proof-tools.
  4143 
  4144 * Method "ferrack" implements quantifier elimination over
  4145 special-purpose dense linear orders using locales (analogous to
  4146 "algebra"). The method is already installed for class
  4147 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  4148 rat, etc.
  4149 
  4150 * Former constant "List.op @" now named "List.append".  Use ML
  4151 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  4152 circumvent possible incompatibilities when working on ML level.
  4153 
  4154 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  4155 
  4156 * New function listsum :: 'a list => 'a for arbitrary monoids.
  4157 Special syntax: "SUM x <- xs. f x" (and latex variants)
  4158 
  4159 * New syntax for Haskell-like list comprehension (input only), eg.
  4160 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  4161 
  4162 * The special syntax for function "filter" has changed from [x :
  4163 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  4164 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  4165 
  4166 * [a..b] is now defined for arbitrary linear orders.  It used to be
  4167 defined on nat only, as an abbreviation for [a..<Suc b]
  4168 INCOMPATIBILITY.
  4169 
  4170 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  4171 
  4172 * New functions "sorted" and "sort" in src/HOL/List.thy.
  4173 
  4174 * New lemma collection field_simps (an extension of ring_simps) for
  4175 manipulating (in)equations involving division. Multiplies with all
  4176 denominators that can be proved to be non-zero (in equations) or
  4177 positive/negative (in inequations).
  4178 
  4179 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  4180 have been improved and renamed to ring_simps, group_simps and
  4181 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  4182 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  4183 
  4184 * Theory Library/Commutative_Ring: switched from recdef to function
  4185 package; constants add, mul, pow now curried.  Infix syntax for
  4186 algebraic operations.
  4187 
  4188 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  4189 INCOMPATIBILITY.
  4190 
  4191 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  4192 INCOMPATIBILITY.
  4193 
  4194 * HOL/records: generalised field-update to take a function on the
  4195 field rather than the new value: r(|A := x|) is translated to A_update
  4196 (K x) r The K-combinator that is internally used is called K_record.
  4197 INCOMPATIBILITY: Usage of the plain update functions has to be
  4198 adapted.
  4199  
  4200 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  4201 * x = 0, which are required for a semiring.  Richer structures do not
  4202 inherit from semiring_0 anymore, because this property is a theorem
  4203 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  4204 there is more to prove, but this is mostly trivial.
  4205 
  4206 * Class "recpower" is generalized to arbitrary monoids, not just
  4207 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  4208 commutativity or semiring properties additionally.
  4209 
  4210 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  4211 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  4212 better use 'abbreviation'.
  4213 
  4214 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  4215 
  4216 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  4217 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  4218 significant changes for setting up numeral syntax for types:
  4219   - New constants Numeral.pred and Numeral.succ instead
  4220       of former Numeral.bin_pred and Numeral.bin_succ.
  4221   - Use integer operations instead of bin_add, bin_mult and so on.
  4222   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  4223   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  4224 
  4225 See src/HOL/Integ/IntArith.thy for an example setup.
  4226 
  4227 * Command 'normal_form' computes the normal form of a term that may
  4228 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  4229 produces ``[b, c, a]'' (without proof).  This command is suitable for
  4230 heavy-duty computations because the functions are compiled to ML
  4231 first.  Correspondingly, a method "normalization" is provided.  See
  4232 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  4233 
  4234 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  4235 25 like -->); output depends on the "iff" print_mode, the default is
  4236 "A = B" (with priority 50).
  4237 
  4238 * Relations less (<) and less_eq (<=) are also available on type bool.
  4239 Modified syntax to disallow nesting without explicit parentheses,
  4240 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  4241 INCOMPATIBILITY.
  4242 
  4243 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  4244 
  4245 * Relation composition operator "op O" now has precedence 75 and binds
  4246 stronger than union and intersection. INCOMPATIBILITY.
  4247 
  4248 * The old set interval syntax "{m..n(}" (and relatives) has been
  4249 removed.  Use "{m..<n}" (and relatives) instead.
  4250 
  4251 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  4252 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  4253 ``declare [[simproc del: neq]]''.
  4254 
  4255 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  4256 True/False.
  4257 
  4258 * Theorem Cons_eq_map_conv no longer declared as "simp".
  4259 
  4260 * Theorem setsum_mult renamed to setsum_right_distrib.
  4261 
  4262 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  4263 ``rule'' method.
  4264 
  4265 * Reimplemented methods "sat" and "satx", with several improvements:
  4266 goals no longer need to be stated as "<prems> ==> False", equivalences
  4267 (i.e. "=" on type bool) are handled, variable names of the form
  4268 "lit_<n>" are no longer reserved, significant speedup.
  4269 
  4270 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  4271 zChaff is still supported as well.
  4272 
  4273 * 'inductive' and 'datatype': provide projections of mutual rules,
  4274 bundled as foo_bar.inducts;
  4275 
  4276 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  4277 Library.
  4278 
  4279 * Library: moved theory Accessible_Part to main HOL.
  4280 
  4281 * Library: added theory Coinductive_List of potentially infinite lists
  4282 as greatest fixed-point.
  4283 
  4284 * Library: added theory AssocList which implements (finite) maps as
  4285 association lists.
  4286 
  4287 * Method "evaluation" solves goals (i.e. a boolean expression)
  4288 efficiently by compiling it to ML.  The goal is "proved" (via an
  4289 oracle) if it evaluates to True.
  4290 
  4291 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  4292 also when invoked by the simplifier.  This results in the Simplifier
  4293 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  4294 Configuration option fast_arith_split_limit=0 recovers the old
  4295 behavior.
  4296 
  4297 * Support for hex (0x20) and binary (0b1001) numerals.
  4298 
  4299 * New method: reify eqs (t), where eqs are equations for an
  4300 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  4301 parameter, computes a term s::'b and a list xs::'a list and proves the
  4302 theorem I xs s = t. This is also known as reification or quoting. The
  4303 resulting theorem is applied to the subgoal to substitute t with I xs
  4304 s.  If t is omitted, the subgoal itself is reified.
  4305 
  4306 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  4307 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  4308 where f is supposed to be a computable function (in the sense of code
  4309 generattion). The method uses reify to compute s and xs as above then
  4310 applies corr_thm and uses normalization by evaluation to "prove" f s =
  4311 r and finally gets the theorem t = r, which is again applied to the
  4312 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  4313 
  4314 * Reflection: Automatic reification now handels binding, an example is
  4315 available in src/HOL/ex/ReflectionEx.thy
  4316 
  4317 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  4318 command 'statespace' that is similar to 'record', but introduces an
  4319 abstract specification based on the locale infrastructure instead of
  4320 HOL types.  This leads to extra flexibility in composing state spaces,
  4321 in particular multiple inheritance and renaming of components.
  4322 
  4323 
  4324 *** HOL-Complex ***
  4325 
  4326 * Hyperreal: Functions root and sqrt are now defined on negative real
  4327 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  4328 Nonnegativity side conditions have been removed from many lemmas, so
  4329 that more subgoals may now be solved by simplification; potential
  4330 INCOMPATIBILITY.
  4331 
  4332 * Real: new type classes formalize real normed vector spaces and
  4333 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  4334 and norm :: 'a => real.
  4335 
  4336 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  4337 reals into other types. The overloaded constant Reals :: 'a set is now
  4338 defined as range of_real; potential INCOMPATIBILITY.
  4339 
  4340 * Real: proper support for ML code generation, including 'quickcheck'.
  4341 Reals are implemented as arbitrary precision rationals.
  4342 
  4343 * Hyperreal: Several constants that previously worked only for the
  4344 reals have been generalized, so they now work over arbitrary vector
  4345 spaces. Type annotations may need to be added in some cases; potential
  4346 INCOMPATIBILITY.
  4347 
  4348   Infinitesimal  :: ('a::real_normed_vector) star set
  4349   HFinite        :: ('a::real_normed_vector) star set
  4350   HInfinite      :: ('a::real_normed_vector) star set
  4351   approx         :: ('a::real_normed_vector) star => 'a star => bool
  4352   monad          :: ('a::real_normed_vector) star => 'a star set
  4353   galaxy         :: ('a::real_normed_vector) star => 'a star set
  4354   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  4355   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  4356   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  4357   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  4358   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  4359   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  4360   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  4361   sgn            :: 'a::real_normed_vector => 'a
  4362   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  4363 
  4364 * Complex: Some complex-specific constants are now abbreviations for
  4365 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  4366 hnorm.  Other constants have been entirely removed in favor of the
  4367 polymorphic versions (INCOMPATIBILITY):
  4368 
  4369   approx        <-- capprox
  4370   HFinite       <-- CFinite
  4371   HInfinite     <-- CInfinite
  4372   Infinitesimal <-- CInfinitesimal
  4373   monad         <-- cmonad
  4374   galaxy        <-- cgalaxy
  4375   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  4376   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  4377   (ns)deriv     <-- (ns)cderiv
  4378 
  4379 
  4380 *** HOL-Algebra ***
  4381 
  4382 * Formalisation of ideals and the quotient construction over rings.
  4383 
  4384 * Order and lattice theory no longer based on records.
  4385 INCOMPATIBILITY.
  4386 
  4387 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  4388 greatest_closed.  INCOMPATIBILITY.
  4389 
  4390 * Method algebra is now set up via an attribute.  For examples see
  4391 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  4392 of algebraic structures.
  4393 
  4394 * Renamed theory CRing to Ring.
  4395 
  4396 
  4397 *** HOL-Nominal ***
  4398 
  4399 * Substantial, yet incomplete support for nominal datatypes (binding
  4400 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  4401 src/HOL/Nominal/Examples.  Prospective users should consult
  4402 http://isabelle.in.tum.de/nominal/
  4403 
  4404 
  4405 *** ML ***
  4406 
  4407 * ML basics: just one true type int, which coincides with IntInf.int
  4408 (even on SML/NJ).
  4409 
  4410 * ML within Isar: antiquotations allow to embed statically-checked
  4411 formal entities in the source, referring to the context available at
  4412 compile-time.  For example:
  4413 
  4414 ML {* @{sort "{zero,one}"} *}
  4415 ML {* @{typ "'a => 'b"} *}
  4416 ML {* @{term "%x. x"} *}
  4417 ML {* @{prop "x == y"} *}
  4418 ML {* @{ctyp "'a => 'b"} *}
  4419 ML {* @{cterm "%x. x"} *}
  4420 ML {* @{cprop "x == y"} *}
  4421 ML {* @{thm asm_rl} *}
  4422 ML {* @{thms asm_rl} *}
  4423 ML {* @{type_name c} *}
  4424 ML {* @{type_syntax c} *}
  4425 ML {* @{const_name c} *}
  4426 ML {* @{const_syntax c} *}
  4427 ML {* @{context} *}
  4428 ML {* @{theory} *}
  4429 ML {* @{theory Pure} *}
  4430 ML {* @{theory_ref} *}
  4431 ML {* @{theory_ref Pure} *}
  4432 ML {* @{simpset} *}
  4433 ML {* @{claset} *}
  4434 ML {* @{clasimpset} *}
  4435 
  4436 The same works for sources being ``used'' within an Isar context.
  4437 
  4438 * ML in Isar: improved error reporting; extra verbosity with
  4439 ML_Context.trace enabled.
  4440 
  4441 * Pure/General/table.ML: the join operations now works via exceptions
  4442 DUP/SAME instead of type option. This is simpler in simple cases, and
  4443 admits slightly more efficient complex applications.
  4444 
  4445 * Pure: 'advanced' translation functions (parse_translation etc.) now
  4446 use Context.generic instead of just theory.
  4447 
  4448 * Pure: datatype Context.generic joins theory/Proof.context and
  4449 provides some facilities for code that works in either kind of
  4450 context, notably GenericDataFun for uniform theory and proof data.
  4451 
  4452 * Pure: simplified internal attribute type, which is now always
  4453 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  4454 local (Proof.context) attributes have been discontinued, while
  4455 minimizing code duplication. Thm.rule_attribute and
  4456 Thm.declaration_attribute build canonical attributes; see also structure
  4457 Context for further operations on Context.generic, notably
  4458 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  4459 declarations and definitions.
  4460 
  4461 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  4462 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  4463 init only required for impure data. INCOMPATIBILITY: empty really need
  4464 to be empty (no dependencies on theory content!)
  4465 
  4466 * Pure/kernel: consts certification ignores sort constraints given in
  4467 signature declarations. (This information is not relevant to the
  4468 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  4469 potential INCOMPATIBILITY.
  4470 
  4471 * Pure: axiomatic type classes are now purely definitional, with
  4472 explicit proofs of class axioms and super class relations performed
  4473 internally. See Pure/axclass.ML for the main internal interfaces --
  4474 notably AxClass.define_class supercedes AxClass.add_axclass, and
  4475 AxClass.axiomatize_class/classrel/arity supersede
  4476 Sign.add_classes/classrel/arities.
  4477 
  4478 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  4479 global/local versions on theory vs. Proof.context have been
  4480 discontinued; Attrib.syntax and Method.syntax have been adapted
  4481 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  4482 attributes, methods, etc.
  4483 
  4484 * Pure: several functions of signature "... -> theory -> theory * ..."
  4485 have been reoriented to "... -> theory -> ... * theory" in order to
  4486 allow natural usage in combination with the ||>, ||>>, |-> and
  4487 fold_map combinators.
  4488 
  4489 * Pure: official theorem names (closed derivations) and additional
  4490 comments (tags) are now strictly separate.  Name hints -- which are
  4491 maintained as tags -- may be attached any time without affecting the
  4492 derivation.
  4493 
  4494 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  4495 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  4496 achieve the old behaviour.
  4497 
  4498 * Pure: the "Goal" constant is now called "prop", supporting a
  4499 slightly more general idea of ``protecting'' meta-level rule
  4500 statements.
  4501 
  4502 * Pure: Logic.(un)varify only works in a global context, which is now
  4503 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  4504 Logic.legacy_(un)varify as temporary workaround.
  4505 
  4506 * Pure: structure Name provides scalable operations for generating
  4507 internal variable names, notably Name.variants etc.  This replaces
  4508 some popular functions from term.ML:
  4509 
  4510   Term.variant		->  Name.variant
  4511   Term.variantlist	->  Name.variant_list
  4512   Term.invent_names	->  Name.invent_list
  4513 
  4514 Note that low-level renaming rarely occurs in new code -- operations
  4515 from structure Variable are used instead (see below).
  4516 
  4517 * Pure: structure Variable provides fundamental operations for proper
  4518 treatment of fixed/schematic variables in a context.  For example,
  4519 Variable.import introduces fixes for schematics of given facts and
  4520 Variable.export reverses the effect (up to renaming) -- this replaces
  4521 various freeze_thaw operations.
  4522 
  4523 * Pure: structure Goal provides simple interfaces for
  4524 init/conclude/finish and tactical prove operations (replacing former
  4525 Tactic.prove).  Goal.prove is the canonical way to prove results
  4526 within a given context; Goal.prove_global is a degraded version for
  4527 theory level goals, including a global Drule.standard.  Note that
  4528 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  4529 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  4530 in a locale context).
  4531 
  4532 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  4533 and type checking (Syntax.check_term etc.), with common combinations
  4534 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  4535 which are considered legacy and await removal.
  4536 
  4537 * Pure/Syntax: generic interfaces for type unchecking
  4538 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  4539 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  4540 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  4541 available for convenience, but refer to the very same operations using
  4542 a mere theory instead of a full context.
  4543 
  4544 * Isar: simplified treatment of user-level errors, using exception
  4545 ERROR of string uniformly.  Function error now merely raises ERROR,
  4546 without any side effect on output channels.  The Isar toplevel takes
  4547 care of proper display of ERROR exceptions.  ML code may use plain
  4548 handle/can/try; cat_error may be used to concatenate errors like this:
  4549 
  4550   ... handle ERROR msg => cat_error msg "..."
  4551 
  4552 Toplevel ML code (run directly or through the Isar toplevel) may be
  4553 embedded into the Isar toplevel with exception display/debug like
  4554 this:
  4555 
  4556   Isar.toplevel (fn () => ...)
  4557 
  4558 INCOMPATIBILITY, removed special transform_error facilities, removed
  4559 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  4560 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  4561 -- use plain ERROR instead.
  4562 
  4563 * Isar: theory setup now has type (theory -> theory), instead of a
  4564 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  4565 
  4566 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  4567 ProofContext.debug/verbose flags.
  4568 
  4569 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  4570 theory before entering a proof state.  Transactions now always see a
  4571 quasi-functional intermediate checkpoint, both in interactive and
  4572 batch mode.
  4573 
  4574 * Isar: simplified interfaces for outer syntax.  Renamed
  4575 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  4576 OuterSyntax.add_parsers -- this functionality is now included in
  4577 OuterSyntax.command etc.  INCOMPATIBILITY.
  4578 
  4579 * Simplifier: the simpset of a running simplification process now
  4580 contains a proof context (cf. Simplifier.the_context), which is the
  4581 very context that the initial simpset has been retrieved from (by
  4582 simpset_of/local_simpset_of).  Consequently, all plug-in components
  4583 (solver, looper etc.) may depend on arbitrary proof data.
  4584 
  4585 * Simplifier.inherit_context inherits the proof context (plus the
  4586 local bounds) of the current simplification process; any simproc
  4587 etc. that calls the Simplifier recursively should do this!  Removed
  4588 former Simplifier.inherit_bounds, which is already included here --
  4589 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  4590 specify an explicit context using Simplifier.context/theory_context.
  4591 
  4592 * Simplifier/Classical Reasoner: more abstract interfaces
  4593 change_simpset/claset for modifying the simpset/claset reference of a
  4594 theory; raw versions simpset/claset_ref etc. have been discontinued --
  4595 INCOMPATIBILITY.
  4596 
  4597 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  4598 "Trueprop" etc.
  4599 
  4600 
  4601 *** System ***
  4602 
  4603 * settings: the default heap location within ISABELLE_HOME_USER now
  4604 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  4605 Isabelle installations.
  4606 
  4607 * isabelle-process: option -S (secure mode) disables some critical
  4608 operations, notably runtime compilation and evaluation of ML source
  4609 code.
  4610 
  4611 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  4612 
  4613 * Support for parallel execution, using native multicore support of
  4614 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  4615 independent theories, according to the given theory header
  4616 specifications. The maximum number of worker threads is specified via
  4617 usedir option -M or the "max-threads" setting in Proof General. A
  4618 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  4619 to 6 on a 8-core machine.  User-code needs to observe certain
  4620 guidelines for thread-safe programming, see appendix A in the Isar
  4621 Implementation manual.
  4622 
  4623 
  4624 
  4625 New in Isabelle2005 (October 2005)
  4626 ----------------------------------
  4627 
  4628 *** General ***
  4629 
  4630 * Theory headers: the new header syntax for Isar theories is
  4631 
  4632   theory <name>
  4633   imports <theory1> ... <theoryN>
  4634   uses <file1> ... <fileM>
  4635   begin
  4636 
  4637 where the 'uses' part is optional.  The previous syntax
  4638 
  4639   theory <name> = <theory1> + ... + <theoryN>:
  4640 
  4641 will disappear in the next release.  Use isatool fixheaders to convert
  4642 existing theory files.  Note that there is no change in ancient
  4643 non-Isar theories now, but these will disappear soon.
  4644 
  4645 * Theory loader: parent theories can now also be referred to via
  4646 relative and absolute paths.
  4647 
  4648 * Command 'find_theorems' searches for a list of criteria instead of a
  4649 list of constants. Known criteria are: intro, elim, dest, name:string,
  4650 simp:term, and any term. Criteria can be preceded by '-' to select
  4651 theorems that do not match. Intro, elim, dest select theorems that
  4652 match the current goal, name:s selects theorems whose fully qualified
  4653 name contain s, and simp:term selects all simplification rules whose
  4654 lhs match term.  Any other term is interpreted as pattern and selects
  4655 all theorems matching the pattern. Available in ProofGeneral under
  4656 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  4657 
  4658   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  4659 
  4660 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  4661 matching the current goal as introduction rule and not having "HOL."
  4662 in their name (i.e. not being defined in theory HOL).
  4663 
  4664 * Command 'thms_containing' has been discontinued in favour of
  4665 'find_theorems'; INCOMPATIBILITY.
  4666 
  4667 * Communication with Proof General is now 8bit clean, which means that
  4668 Unicode text in UTF-8 encoding may be used within theory texts (both
  4669 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4670 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4671 
  4672   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4673   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4674 
  4675 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4676 Classical Reasoner.  Typical big applications run around 2 times
  4677 faster.
  4678 
  4679 
  4680 *** Document preparation ***
  4681 
  4682 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4683 of raw sources.  Only those symbols that do not require additional
  4684 LaTeX packages (depending on comments in isabellesym.sty) are
  4685 displayed properly, everything else is left verbatim.  isatool display
  4686 and isatool print are used as front ends (these are subject to the
  4687 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4688 
  4689 * Command tags control specific markup of certain regions of text,
  4690 notably folding and hiding.  Predefined tags include "theory" (for
  4691 theory begin and end), "proof" for proof commands, and "ML" for
  4692 commands involving ML code; the additional tags "visible" and
  4693 "invisible" are unused by default.  Users may give explicit tag
  4694 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4695 interpretation of tags is determined by the LaTeX job during document
  4696 preparation: see option -V of isatool usedir, or options -n and -t of
  4697 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4698 \isadroptag.
  4699 
  4700 Several document versions may be produced at the same time via isatool
  4701 usedir (the generated index.html will link all of them).  Typical
  4702 specifications include ''-V document=theory,proof,ML'' to present
  4703 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4704 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4705 these parts without any formal replacement text.  The Isabelle site
  4706 default settings produce ''document'' and ''outline'' versions as
  4707 specified above.
  4708 
  4709 * Several new antiquotations:
  4710 
  4711   @{term_type term} prints a term with its type annotated;
  4712 
  4713   @{typeof term} prints the type of a term;
  4714 
  4715   @{const const} is the same as @{term const}, but checks that the
  4716   argument is a known logical constant;
  4717 
  4718   @{term_style style term} and @{thm_style style thm} print a term or
  4719   theorem applying a "style" to it
  4720 
  4721   @{ML text}
  4722 
  4723 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4724 definitions, equations, inequations etc., 'concl' printing only the
  4725 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4726 to print the specified premise.  TermStyle.add_style provides an ML
  4727 interface for introducing further styles.  See also the "LaTeX Sugar"
  4728 document practical applications.  The ML antiquotation prints
  4729 type-checked ML expressions verbatim.
  4730 
  4731 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4732 and 'text' support optional locale specification '(in loc)', which
  4733 specifies the default context for interpreting antiquotations.  For
  4734 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4735 
  4736 * Option 'locale=NAME' of antiquotations specifies an alternative
  4737 context interpreting the subsequent argument.  For example: @{thm
  4738 [locale=lattice] inf_assoc}.
  4739 
  4740 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4741 a proof context.
  4742 
  4743 * Proper output of antiquotations for theory commands involving a
  4744 proof context (such as 'locale' or 'theorem (in loc) ...').
  4745 
  4746 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4747 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4748 
  4749 * isatool usedir: new option -C (default true) controls whether option
  4750 -D should include a copy of the original document directory; -C false
  4751 prevents unwanted effects such as copying of administrative CVS data.
  4752 
  4753 
  4754 *** Pure ***
  4755 
  4756 * Considerably improved version of 'constdefs' command.  Now performs
  4757 automatic type-inference of declared constants; additional support for
  4758 local structure declarations (cf. locales and HOL records), see also
  4759 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4760 sequential dependencies of definitions within a single 'constdefs'
  4761 section; moreover, the declared name needs to be an identifier.  If
  4762 all fails, consider to fall back on 'consts' and 'defs' separately.
  4763 
  4764 * Improved indexed syntax and implicit structures.  First of all,
  4765 indexed syntax provides a notational device for subscripted
  4766 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4767 expressions.  Secondly, in a local context with structure
  4768 declarations, number indexes \<^sub>n or the empty index (default
  4769 number 1) refer to a certain fixed variable implicitly; option
  4770 show_structs controls printing of implicit structures.  Typical
  4771 applications of these concepts involve record types and locales.
  4772 
  4773 * New command 'no_syntax' removes grammar declarations (and
  4774 translations) resulting from the given syntax specification, which is
  4775 interpreted in the same manner as for the 'syntax' command.
  4776 
  4777 * 'Advanced' translation functions (parse_translation etc.) may depend
  4778 on the signature of the theory context being presently used for
  4779 parsing/printing, see also isar-ref manual.
  4780 
  4781 * Improved 'oracle' command provides a type-safe interface to turn an
  4782 ML expression of type theory -> T -> term into a primitive rule of
  4783 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4784 is already included here); see also FOL/ex/IffExample.thy;
  4785 INCOMPATIBILITY.
  4786 
  4787 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4788 before); "cI" is no longer bound, use "c.intro" instead.
  4789 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4790 axclasses vs. locales.
  4791 
  4792 * Improved internal renaming of symbolic identifiers -- attach primes
  4793 instead of base 26 numbers.
  4794 
  4795 * New flag show_question_marks controls printing of leading question
  4796 marks in schematic variable names.
  4797 
  4798 * In schematic variable names, *any* symbol following \<^isub> or
  4799 \<^isup> is now treated as part of the base name.  For example, the
  4800 following works without printing of awkward ".0" indexes:
  4801 
  4802   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4803     by simp
  4804 
  4805 * Inner syntax includes (*(*nested*) comments*).
  4806 
  4807 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4808 annotations as "(00...)".
  4809 
  4810 * Clear separation of logical types and nonterminals, where the latter
  4811 may only occur in 'syntax' specifications or type abbreviations.
  4812 Before that distinction was only partially implemented via type class
  4813 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4814 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4815 exotic syntax specifications may require further adaption
  4816 (e.g. Cube/Cube.thy).
  4817 
  4818 * Removed obsolete type class "logic", use the top sort {} instead.
  4819 Note that non-logical types should be declared as 'nonterminals'
  4820 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4821 specifications.
  4822 
  4823 * Attributes 'induct' and 'cases': type or set names may now be
  4824 locally fixed variables as well.
  4825 
  4826 * Simplifier: can now control the depth to which conditional rewriting
  4827 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4828 Limit.
  4829 
  4830 * Simplifier: simplification procedures may now take the current
  4831 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4832 interface), which is very useful for calling the Simplifier
  4833 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4834 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4835 low-level mk_simproc no longer applies Logic.varify internally, to
  4836 allow for use in a context of fixed variables.
  4837 
  4838 * thin_tac now works even if the assumption being deleted contains !!
  4839 or ==>.  More generally, erule now works even if the major premise of
  4840 the elimination rule contains !! or ==>.
  4841 
  4842 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4843 
  4844 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4845 from Pure, which contains all common declarations already.  Both
  4846 theories are defined via plain Isabelle/Isar .thy files.
  4847 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4848 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4849 use isatool fixcpure to adapt your theory and ML sources.
  4850 
  4851 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4852 selections of theorems in named facts via index ranges.
  4853 
  4854 * 'print_theorems': in theory mode, really print the difference
  4855 wrt. the last state (works for interactive theory development only),
  4856 in proof mode print all local facts (cf. 'print_facts');
  4857 
  4858 * 'hide': option '(open)' hides only base names.
  4859 
  4860 * More efficient treatment of intermediate checkpoints in interactive
  4861 theory development.
  4862 
  4863 * Code generator is now invoked via code_module (incremental code
  4864 generation) and code_library (modular code generation, ML structures
  4865 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4866 must be quoted when used as identifiers.
  4867 
  4868 * New 'value' command for reading, evaluating and printing terms using
  4869 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4870 quoted when used as identifier.
  4871 
  4872 
  4873 *** Locales ***
  4874 
  4875 * New commands for the interpretation of locale expressions in
  4876 theories (1), locales (2) and proof contexts (3).  These generate
  4877 proof obligations from the expression specification.  After the
  4878 obligations have been discharged, theorems of the expression are added
  4879 to the theory, target locale or proof context.  The synopsis of the
  4880 commands is a follows:
  4881 
  4882   (1) interpretation expr inst
  4883   (2) interpretation target < expr
  4884   (3) interpret expr inst
  4885 
  4886 Interpretation in theories and proof contexts require a parameter
  4887 instantiation of terms from the current context.  This is applied to
  4888 specifications and theorems of the interpreted expression.
  4889 Interpretation in locales only permits parameter renaming through the
  4890 locale expression.  Interpretation is smart in that interpretations
  4891 that are active already do not occur in proof obligations, neither are
  4892 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4893 inspect active interpretations of a particular locale.  For details,
  4894 see the Isar Reference manual.  Examples can be found in
  4895 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4896 
  4897 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4898 'interpret' instead.
  4899 
  4900 * New context element 'constrains' for adding type constraints to
  4901 parameters.
  4902 
  4903 * Context expressions: renaming of parameters with syntax
  4904 redeclaration.
  4905 
  4906 * Locale declaration: 'includes' disallowed.
  4907 
  4908 * Proper static binding of attribute syntax -- i.e. types / terms /
  4909 facts mentioned as arguments are always those of the locale definition
  4910 context, independently of the context of later invocations.  Moreover,
  4911 locale operations (renaming and type / term instantiation) are applied
  4912 to attribute arguments as expected.
  4913 
  4914 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4915 actual attributes; rare situations may require Attrib.attribute to
  4916 embed those attributes into Attrib.src that lack concrete syntax.
  4917 Attribute implementations need to cooperate properly with the static
  4918 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4919 Attrib.XXX_thm etc. already do the right thing without further
  4920 intervention.  Only unusual applications -- such as "where" or "of"
  4921 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4922 on the context and the facts involved -- may have to assign parsed
  4923 values to argument tokens explicitly.
  4924 
  4925 * Changed parameter management in theorem generation for long goal
  4926 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4927 theorem statement in rare situations.
  4928 
  4929 * Locale inspection command 'print_locale' omits notes elements.  Use
  4930 'print_locale!' to have them included in the output.
  4931 
  4932 
  4933 *** Provers ***
  4934 
  4935 * Provers/hypsubst.ML: improved version of the subst method, for
  4936 single-step rewriting: it now works in bound variable contexts. New is
  4937 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  4938 rewrite a different subterm than the original subst method, which is
  4939 still available as 'simplesubst'.
  4940 
  4941 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  4942 and quasi orders.
  4943 
  4944 * Provers/trancl.ML: new transitivity reasoner for transitive and
  4945 reflexive-transitive closure of relations.
  4946 
  4947 * Provers/blast.ML: new reference depth_limit to make blast's depth
  4948 limit (previously hard-coded with a value of 20) user-definable.
  4949 
  4950 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  4951 is peformed already.  Object-logics merely need to finish their
  4952 initial simpset configuration as before.  INCOMPATIBILITY.
  4953 
  4954 
  4955 *** HOL ***
  4956 
  4957 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  4958 
  4959   syntax (epsilon)
  4960     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  4961 
  4962 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  4963 and x-symbol; use option '-m epsilon' to get it actually printed.
  4964 Moreover, the mathematically important symbolic identifier \<epsilon>
  4965 becomes available as variable, constant etc.  INCOMPATIBILITY,
  4966 
  4967 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  4968 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  4969 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  4970 support corresponding Isar calculations.
  4971 
  4972 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  4973 instead of ":".
  4974 
  4975 * theory SetInterval: changed the syntax for open intervals:
  4976 
  4977   Old       New
  4978   {..n(}    {..<n}
  4979   {)n..}    {n<..}
  4980   {m..n(}   {m..<n}
  4981   {)m..n}   {m<..n}
  4982   {)m..n(}  {m<..<n}
  4983 
  4984 The old syntax is still supported but will disappear in the next
  4985 release.  For conversion use the following Emacs search and replace
  4986 patterns (these are not perfect but work quite well):
  4987 
  4988   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  4989   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  4990 
  4991 * Theory Commutative_Ring (in Library): method comm_ring for proving
  4992 equalities in commutative rings; method 'algebra' provides a generic
  4993 interface.
  4994 
  4995 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  4996 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  4997 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  4998 be a tuple pattern.
  4999 
  5000 Some new syntax forms are available:
  5001 
  5002   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  5003   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  5004   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  5005   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  5006 
  5007 The latter form "\<Sum>x < k. e" used to be based on a separate
  5008 function "Summation", which has been discontinued.
  5009 
  5010 * theory Finite_Set: in structured induction proofs, the insert case
  5011 is now 'case (insert x F)' instead of the old counterintuitive 'case
  5012 (insert F x)'.
  5013 
  5014 * The 'refute' command has been extended to support a much larger
  5015 fragment of HOL, including axiomatic type classes, constdefs and
  5016 typedefs, inductive datatypes and recursion.
  5017 
  5018 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  5019 Requires zChaff with proof generation to be installed.  See
  5020 HOL/ex/SAT_Examples.thy for examples.
  5021 
  5022 * Datatype induction via method 'induct' now preserves the name of the
  5023 induction variable. For example, when proving P(xs::'a list) by
  5024 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  5025 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  5026 in unstructured proof scripts.
  5027 
  5028 * Reworked implementation of records.  Improved scalability for
  5029 records with many fields, avoiding performance problems for type
  5030 inference. Records are no longer composed of nested field types, but
  5031 of nested extension types. Therefore the record type only grows linear
  5032 in the number of extensions and not in the number of fields.  The
  5033 top-level (users) view on records is preserved.  Potential
  5034 INCOMPATIBILITY only in strange cases, where the theory depends on the
  5035 old record representation. The type generated for a record is called
  5036 <record_name>_ext_type.
  5037 
  5038 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  5039 proofs triggered by a record definition or a simproc (if
  5040 quick_and_dirty is enabled).  Definitions of large records can take
  5041 quite long.
  5042 
  5043 New simproc record_upd_simproc for simplification of multiple record
  5044 updates enabled by default.  Moreover, trivial updates are also
  5045 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  5046 occasionally, since simplification is more powerful by default.
  5047 
  5048 * typedef: proper support for polymorphic sets, which contain extra
  5049 type-variables in the term.
  5050 
  5051 * Simplifier: automatically reasons about transitivity chains
  5052 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  5053 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  5054 old proofs break occasionally as simplification may now solve more
  5055 goals than previously.
  5056 
  5057 * Simplifier: converts x <= y into x = y if assumption y <= x is
  5058 present.  Works for all partial orders (class "order"), in particular
  5059 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  5060 just like y <= x.
  5061 
  5062 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  5063 bound variable or a constant then the let is unfolded.  Otherwise
  5064 first a is simplified to b, and then f b is simplified to g. If
  5065 possible we abstract b from g arriving at "let x = b in h x",
  5066 otherwise we unfold the let and arrive at g.  The simproc can be
  5067 enabled/disabled by the reference use_let_simproc.  Potential
  5068 INCOMPATIBILITY since simplification is more powerful by default.
  5069 
  5070 * Classical reasoning: the meson method now accepts theorems as arguments.
  5071 
  5072 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  5073 jobs to provide advice on the provability of subgoals.
  5074 
  5075 * Theory OrderedGroup and Ring_and_Field: various additions and
  5076 improvements to faciliate calculations involving equalities and
  5077 inequalities.
  5078 
  5079 The following theorems have been eliminated or modified
  5080 (INCOMPATIBILITY):
  5081 
  5082   abs_eq             now named abs_of_nonneg
  5083   abs_of_ge_0        now named abs_of_nonneg
  5084   abs_minus_eq       now named abs_of_nonpos
  5085   imp_abs_id         now named abs_of_nonneg
  5086   imp_abs_neg_id     now named abs_of_nonpos
  5087   mult_pos           now named mult_pos_pos
  5088   mult_pos_le        now named mult_nonneg_nonneg
  5089   mult_pos_neg_le    now named mult_nonneg_nonpos
  5090   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  5091   mult_neg           now named mult_neg_neg
  5092   mult_neg_le        now named mult_nonpos_nonpos
  5093 
  5094 * The following lemmas in Ring_and_Field have been added to the simplifier:
  5095      
  5096      zero_le_square
  5097      not_square_less_zero 
  5098 
  5099   The following lemmas have been deleted from Real/RealPow:
  5100   
  5101      realpow_zero_zero
  5102      realpow_two
  5103      realpow_less
  5104      zero_le_power
  5105      realpow_two_le
  5106      abs_realpow_two
  5107      realpow_two_abs     
  5108 
  5109 * Theory Parity: added rules for simplifying exponents.
  5110 
  5111 * Theory List:
  5112 
  5113 The following theorems have been eliminated or modified
  5114 (INCOMPATIBILITY):
  5115 
  5116   list_all_Nil       now named list_all.simps(1)
  5117   list_all_Cons      now named list_all.simps(2)
  5118   list_all_conv      now named list_all_iff
  5119   set_mem_eq         now named mem_iff
  5120 
  5121 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  5122 asymptotic "big O" calculations.  See the notes in BigO.thy.
  5123 
  5124 
  5125 *** HOL-Complex ***
  5126 
  5127 * Theory RealDef: better support for embedding natural numbers and
  5128 integers in the reals.
  5129 
  5130 The following theorems have been eliminated or modified
  5131 (INCOMPATIBILITY):
  5132 
  5133   exp_ge_add_one_self  now requires no hypotheses
  5134   real_of_int_add      reversed direction of equality (use [symmetric])
  5135   real_of_int_minus    reversed direction of equality (use [symmetric])
  5136   real_of_int_diff     reversed direction of equality (use [symmetric])
  5137   real_of_int_mult     reversed direction of equality (use [symmetric])
  5138 
  5139 * Theory RComplete: expanded support for floor and ceiling functions.
  5140 
  5141 * Theory Ln is new, with properties of the natural logarithm
  5142 
  5143 * Hyperreal: There is a new type constructor "star" for making
  5144 nonstandard types.  The old type names are now type synonyms:
  5145 
  5146   hypreal = real star
  5147   hypnat = nat star
  5148   hcomplex = complex star
  5149 
  5150 * Hyperreal: Many groups of similarly-defined constants have been
  5151 replaced by polymorphic versions (INCOMPATIBILITY):
  5152 
  5153   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  5154 
  5155   starset      <-- starsetNat, starsetC
  5156   *s*          <-- *sNat*, *sc*
  5157   starset_n    <-- starsetNat_n, starsetC_n
  5158   *sn*         <-- *sNatn*, *scn*
  5159   InternalSets <-- InternalNatSets, InternalCSets
  5160 
  5161   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  5162   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  5163   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  5164   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  5165   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  5166 
  5167 * Hyperreal: Many type-specific theorems have been removed in favor of
  5168 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  5169 
  5170   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  5171   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  5172   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  5173   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  5174   right_minus <-- hypreal_add_minus
  5175   left_minus <-- {hypreal,hcomplex}_add_minus_left
  5176   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  5177   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  5178   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  5179   mult_1_right <-- hcomplex_mult_one_right
  5180   mult_zero_left <-- hcomplex_mult_zero_left
  5181   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  5182   right_distrib <-- hypnat_add_mult_distrib2
  5183   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  5184   right_inverse <-- hypreal_mult_inverse
  5185   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  5186   order_refl <-- {hypreal,hypnat}_le_refl
  5187   order_trans <-- {hypreal,hypnat}_le_trans
  5188   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  5189   order_less_le <-- {hypreal,hypnat}_less_le
  5190   linorder_linear <-- {hypreal,hypnat}_le_linear
  5191   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  5192   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  5193   add_nonneg_nonneg <-- hypreal_le_add_order
  5194 
  5195 * Hyperreal: Separate theorems having to do with type-specific
  5196 versions of constants have been merged into theorems that apply to the
  5197 new polymorphic constants (INCOMPATIBILITY):
  5198 
  5199   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  5200   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  5201   STAR_Un <-- {STAR,NatStar,STARC}_Un
  5202   STAR_Int <-- {STAR,NatStar,STARC}_Int
  5203   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  5204   STAR_subset <-- {STAR,NatStar,STARC}_subset
  5205   STAR_mem <-- {STAR,NatStar,STARC}_mem
  5206   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  5207   STAR_diff <-- {STAR,STARC}_diff
  5208   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  5209     STARC_hcomplex_of_complex}_image_subset
  5210   starset_n_Un <-- starset{Nat,C}_n_Un
  5211   starset_n_Int <-- starset{Nat,C}_n_Int
  5212   starset_n_Compl <-- starset{Nat,C}_n_Compl
  5213   starset_n_diff <-- starset{Nat,C}_n_diff
  5214   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  5215   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  5216   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  5217   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  5218   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  5219   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  5220   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  5221   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  5222   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  5223   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  5224   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  5225   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  5226   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  5227   starfun_diff <-- starfun{C,RC,CR}_diff
  5228   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  5229   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  5230   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  5231   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  5232   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  5233   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  5234   starfun_Id <-- starfunC_Id
  5235   starfun_approx <-- starfun{Nat,CR}_approx
  5236   starfun_capprox <-- starfun{C,RC}_capprox
  5237   starfun_abs <-- starfunNat_rabs
  5238   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  5239   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  5240   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  5241   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  5242   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  5243   starfun_add_approx <-- starfunCR_add_approx
  5244   starfun_inverse_inverse <-- starfunC_inverse_inverse
  5245   starfun_divide <-- starfun{C,CR,RC}_divide
  5246   starfun_n <-- starfun{Nat,C}_n
  5247   starfun_n_mult <-- starfun{Nat,C}_n_mult
  5248   starfun_n_add <-- starfun{Nat,C}_n_add
  5249   starfun_n_add_minus <-- starfunNat_n_add_minus
  5250   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  5251   starfun_n_minus <-- starfun{Nat,C}_n_minus
  5252   starfun_n_eq <-- starfun{Nat,C}_n_eq
  5253 
  5254   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  5255   star_n_minus <-- {hypreal,hcomplex}_minus
  5256   star_n_diff <-- {hypreal,hcomplex}_diff
  5257   star_n_mult <-- {hypreal,hcomplex}_mult
  5258   star_n_inverse <-- {hypreal,hcomplex}_inverse
  5259   star_n_le <-- {hypreal,hypnat}_le
  5260   star_n_less <-- {hypreal,hypnat}_less
  5261   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  5262   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  5263   star_n_abs <-- hypreal_hrabs
  5264   star_n_divide <-- hcomplex_divide
  5265 
  5266   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  5267   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  5268   star_of_diff <-- hypreal_of_real_diff
  5269   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  5270   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  5271   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  5272   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  5273   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  5274   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  5275   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  5276   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  5277   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  5278   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  5279   star_of_number_of <-- {hypreal,hcomplex}_number_of
  5280   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  5281   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  5282   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  5283   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  5284   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  5285   star_of_power <-- hypreal_of_real_power
  5286   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  5287 
  5288 * Hyperreal: new method "transfer" that implements the transfer
  5289 principle of nonstandard analysis. With a subgoal that mentions
  5290 nonstandard types like "'a star", the command "apply transfer"
  5291 replaces it with an equivalent one that mentions only standard types.
  5292 To be successful, all free variables must have standard types; non-
  5293 standard variables must have explicit universal quantifiers.
  5294 
  5295 * Hyperreal: A theory of Taylor series.
  5296 
  5297 
  5298 *** HOLCF ***
  5299 
  5300 * Discontinued special version of 'constdefs' (which used to support
  5301 continuous functions) in favor of the general Pure one with full
  5302 type-inference.
  5303 
  5304 * New simplification procedure for solving continuity conditions; it
  5305 is much faster on terms with many nested lambda abstractions (cubic
  5306 instead of exponential time).
  5307 
  5308 * New syntax for domain package: selector names are now optional.
  5309 Parentheses should be omitted unless argument is lazy, for example:
  5310 
  5311   domain 'a stream = cons "'a" (lazy "'a stream")
  5312 
  5313 * New command 'fixrec' for defining recursive functions with pattern
  5314 matching; defining multiple functions with mutual recursion is also
  5315 supported.  Patterns may include the constants cpair, spair, up, sinl,
  5316 sinr, or any data constructor defined by the domain package. The given
  5317 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  5318 syntax and examples.
  5319 
  5320 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  5321 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  5322 but the proof obligation additionally includes an admissibility
  5323 requirement. The packages generate instances of class cpo or pcpo,
  5324 with continuity and strictness theorems for Rep and Abs.
  5325 
  5326 * HOLCF: Many theorems have been renamed according to a more standard naming
  5327 scheme (INCOMPATIBILITY):
  5328 
  5329   foo_inject:  "foo$x = foo$y ==> x = y"
  5330   foo_eq:      "(foo$x = foo$y) = (x = y)"
  5331   foo_less:    "(foo$x << foo$y) = (x << y)"
  5332   foo_strict:  "foo$UU = UU"
  5333   foo_defined: "... ==> foo$x ~= UU"
  5334   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  5335 
  5336 
  5337 *** ZF ***
  5338 
  5339 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  5340 including the First Isomorphism Theorem (on quotienting by the kernel
  5341 of a homomorphism).
  5342 
  5343 * ZF/Simplifier: install second copy of type solver that actually
  5344 makes use of TC rules declared to Isar proof contexts (or locales);
  5345 the old version is still required for ML proof scripts.
  5346 
  5347 
  5348 *** Cube ***
  5349 
  5350 * Converted to Isar theory format; use locales instead of axiomatic
  5351 theories.
  5352 
  5353 
  5354 *** ML ***
  5355 
  5356 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  5357 for ||>, ||>>, |>>,
  5358 
  5359 * Pure/library.ML no longer defines its own option datatype, but uses
  5360 that of the SML basis, which has constructors NONE and SOME instead of
  5361 None and Some, as well as exception Option.Option instead of OPTION.
  5362 The functions the, if_none, is_some, is_none have been adapted
  5363 accordingly, while Option.map replaces apsome.
  5364 
  5365 * Pure/library.ML: the exception LIST has been given up in favour of
  5366 the standard exceptions Empty and Subscript, as well as
  5367 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  5368 superceded by the standard hd and tl functions etc.
  5369 
  5370 A number of basic list functions are no longer exported to the ML
  5371 toplevel, as they are variants of predefined functions.  The following
  5372 suggests how one can translate existing code:
  5373 
  5374     rev_append xs ys = List.revAppend (xs, ys)
  5375     nth_elem (i, xs) = List.nth (xs, i)
  5376     last_elem xs = List.last xs
  5377     flat xss = List.concat xss
  5378     seq fs = List.app fs
  5379     partition P xs = List.partition P xs
  5380     mapfilter f xs = List.mapPartial f xs
  5381 
  5382 * Pure/library.ML: several combinators for linear functional
  5383 transformations, notably reverse application and composition:
  5384 
  5385   x |> f                f #> g
  5386   (x, y) |-> f          f #-> g
  5387 
  5388 * Pure/library.ML: introduced/changed precedence of infix operators:
  5389 
  5390   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  5391   infix 2 ?;
  5392   infix 3 o oo ooo oooo;
  5393   infix 4 ~~ upto downto;
  5394 
  5395 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  5396 infix operators.
  5397 
  5398 * Pure/library.ML: natural list combinators fold, fold_rev, and
  5399 fold_map support linear functional transformations and nesting.  For
  5400 example:
  5401 
  5402   fold f [x1, ..., xN] y =
  5403     y |> f x1 |> ... |> f xN
  5404 
  5405   (fold o fold) f [xs1, ..., xsN] y =
  5406     y |> fold f xs1 |> ... |> fold f xsN
  5407 
  5408   fold f [x1, ..., xN] =
  5409     f x1 #> ... #> f xN
  5410 
  5411   (fold o fold) f [xs1, ..., xsN] =
  5412     fold f xs1 #> ... #> fold f xsN
  5413 
  5414 * Pure/library.ML: the following selectors on type 'a option are
  5415 available:
  5416 
  5417   the:               'a option -> 'a  (*partial*)
  5418   these:             'a option -> 'a  where 'a = 'b list
  5419   the_default: 'a -> 'a option -> 'a
  5420   the_list:          'a option -> 'a list
  5421 
  5422 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5423 basic operations for association lists, following natural argument
  5424 order; moreover the explicit equality predicate passed here avoids
  5425 potentially expensive polymorphic runtime equality checks.
  5426 The old functions may be expressed as follows:
  5427 
  5428   assoc = uncurry (AList.lookup (op =))
  5429   assocs = these oo AList.lookup (op =)
  5430   overwrite = uncurry (AList.update (op =)) o swap
  5431 
  5432 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5433 
  5434   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  5435   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  5436 
  5437 replacing make_keylist and keyfilter (occassionally used)
  5438 Naive rewrites:
  5439 
  5440   make_keylist = AList.make
  5441   keyfilter = AList.find (op =)
  5442 
  5443 * eq_fst and eq_snd now take explicit equality parameter, thus
  5444   avoiding eqtypes. Naive rewrites:
  5445 
  5446     eq_fst = eq_fst (op =)
  5447     eq_snd = eq_snd (op =)
  5448 
  5449 * Removed deprecated apl and apr (rarely used).
  5450   Naive rewrites:
  5451 
  5452     apl (n, op) =>>= curry op n
  5453     apr (op, m) =>>= fn n => op (n, m)
  5454 
  5455 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  5456 provides a reasonably efficient light-weight implementation of sets as
  5457 lists.
  5458 
  5459 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  5460 few new operations; existing lookup and update are now curried to
  5461 follow natural argument order (for use with fold etc.);
  5462 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  5463 
  5464 * Pure/General: output via the Isabelle channels of
  5465 writeln/warning/error etc. is now passed through Output.output, with a
  5466 hook for arbitrary transformations depending on the print_mode
  5467 (cf. Output.add_mode -- the first active mode that provides a output
  5468 function wins).  Already formatted output may be embedded into further
  5469 text via Output.raw; the result of Pretty.string_of/str_of and derived
  5470 functions (string_of_term/cterm/thm etc.) is already marked raw to
  5471 accommodate easy composition of diagnostic messages etc.  Programmers
  5472 rarely need to care about Output.output or Output.raw at all, with
  5473 some notable exceptions: Output.output is required when bypassing the
  5474 standard channels (writeln etc.), or in token translations to produce
  5475 properly formatted results; Output.raw is required when capturing
  5476 already output material that will eventually be presented to the user
  5477 a second time.  For the default print mode, both Output.output and
  5478 Output.raw have no effect.
  5479 
  5480 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  5481 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  5482 cumulative results are displayed at the end of a batch session.
  5483 
  5484 * Pure/General: File.sysify_path and File.quote_sysify path have been
  5485 replaced by File.platform_path and File.shell_path (with appropriate
  5486 hooks).  This provides a clean interface for unusual systems where the
  5487 internal and external process view of file names are different.
  5488 
  5489 * Pure: more efficient orders for basic syntactic entities: added
  5490 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  5491 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  5492 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  5493 orders now -- potential INCOMPATIBILITY for code that depends on a
  5494 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  5495 Library.sort_strings on result).
  5496 
  5497 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  5498 fold_types traverse types/terms from left to right, observing natural
  5499 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  5500 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  5501 
  5502 * Pure: name spaces have been refined, with significant changes of the
  5503 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  5504 to extern(_table).  The plain name entry path is superceded by a
  5505 general 'naming' context, which also includes the 'policy' to produce
  5506 a fully qualified name and external accesses of a fully qualified
  5507 name; NameSpace.extend is superceded by context dependent
  5508 Sign.declare_name.  Several theory and proof context operations modify
  5509 the naming context.  Especially note Theory.restore_naming and
  5510 ProofContext.restore_naming to get back to a sane state; note that
  5511 Theory.add_path is no longer sufficient to recover from
  5512 Theory.absolute_path in particular.
  5513 
  5514 * Pure: new flags short_names (default false) and unique_names
  5515 (default true) for controlling output of qualified names.  If
  5516 short_names is set, names are printed unqualified.  If unique_names is
  5517 reset, the name prefix is reduced to the minimum required to achieve
  5518 the original result when interning again, even if there is an overlap
  5519 with earlier declarations.
  5520 
  5521 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  5522 now 'extend', and 'merge' gets an additional Pretty.pp argument
  5523 (useful for printing error messages).  INCOMPATIBILITY.
  5524 
  5525 * Pure: major reorganization of the theory context.  Type Sign.sg and
  5526 Theory.theory are now identified, referring to the universal
  5527 Context.theory (see Pure/context.ML).  Actual signature and theory
  5528 content is managed as theory data.  The old code and interfaces were
  5529 spread over many files and structures; the new arrangement introduces
  5530 considerable INCOMPATIBILITY to gain more clarity:
  5531 
  5532   Context -- theory management operations (name, identity, inclusion,
  5533     parents, ancestors, merge, etc.), plus generic theory data;
  5534 
  5535   Sign -- logical signature and syntax operations (declaring consts,
  5536     types, etc.), plus certify/read for common entities;
  5537 
  5538   Theory -- logical theory operations (stating axioms, definitions,
  5539     oracles), plus a copy of logical signature operations (consts,
  5540     types, etc.); also a few basic management operations (Theory.copy,
  5541     Theory.merge, etc.)
  5542 
  5543 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  5544 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  5545 for convenience -- they merely return the theory.
  5546 
  5547 * Pure: type Type.tsig is superceded by theory in most interfaces.
  5548 
  5549 * Pure: the Isar proof context type is already defined early in Pure
  5550 as Context.proof (note that ProofContext.context and Proof.context are
  5551 aliases, where the latter is the preferred name).  This enables other
  5552 Isabelle components to refer to that type even before Isar is present.
  5553 
  5554 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  5555 typeK, constK, axiomK, oracleK), but provide explicit operations for
  5556 any of these kinds.  For example, Sign.intern typeK is now
  5557 Sign.intern_type, Theory.hide_space Sign.typeK is now
  5558 Theory.hide_types.  Also note that former
  5559 Theory.hide_classes/types/consts are now
  5560 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  5561 internalize their arguments!  INCOMPATIBILITY.
  5562 
  5563 * Pure: get_thm interface (of PureThy and ProofContext) expects
  5564 datatype thmref (with constructors Name and NameSelection) instead of
  5565 plain string -- INCOMPATIBILITY;
  5566 
  5567 * Pure: cases produced by proof methods specify options, where NONE
  5568 means to remove case bindings -- INCOMPATIBILITY in
  5569 (RAW_)METHOD_CASES.
  5570 
  5571 * Pure: the following operations retrieve axioms or theorems from a
  5572 theory node or theory hierarchy, respectively:
  5573 
  5574   Theory.axioms_of: theory -> (string * term) list
  5575   Theory.all_axioms_of: theory -> (string * term) list
  5576   PureThy.thms_of: theory -> (string * thm) list
  5577   PureThy.all_thms_of: theory -> (string * thm) list
  5578 
  5579 * Pure: print_tac now outputs the goal through the trace channel.
  5580 
  5581 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  5582 Reference Toplevel.debug (default false) controls detailed printing
  5583 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  5584 controls execution profiling -- set to 1 for time and 2 for space
  5585 (both increase the runtime).
  5586 
  5587 * Isar session: The initial use of ROOT.ML is now always timed,
  5588 i.e. the log will show the actual process times, in contrast to the
  5589 elapsed wall-clock time that the outer shell wrapper produces.
  5590 
  5591 * Simplifier: improved handling of bound variables (nameless
  5592 representation, avoid allocating new strings).  Simprocs that invoke
  5593 the Simplifier recursively should use Simplifier.inherit_bounds to
  5594 avoid local name clashes.  Failure to do so produces warnings
  5595 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  5596 for further details.
  5597 
  5598 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  5599 bindings for all theorems stored within a given theory; this may help
  5600 in porting non-Isar theories to Isar ones, while keeping ML proof
  5601 scripts for the time being.
  5602 
  5603 * ML operator HTML.with_charset specifies the charset begin used for
  5604 generated HTML files.  For example:
  5605 
  5606   HTML.with_charset "utf-8" use_thy "Hebrew";
  5607   HTML.with_charset "utf-8" use_thy "Chinese";
  5608 
  5609 
  5610 *** System ***
  5611 
  5612 * Allow symlinks to all proper Isabelle executables (Isabelle,
  5613 isabelle, isatool etc.).
  5614 
  5615 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  5616 isatool doc, isatool mkdir, display_drafts etc.).
  5617 
  5618 * isatool usedir: option -f allows specification of the ML file to be
  5619 used by Isabelle; default is ROOT.ML.
  5620 
  5621 * New isatool version outputs the version identifier of the Isabelle
  5622 distribution being used.
  5623 
  5624 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  5625 (containing Boolean satisfiability problems) into Isabelle/HOL
  5626 theories.
  5627 
  5628 
  5629 
  5630 New in Isabelle2004 (April 2004)
  5631 --------------------------------
  5632 
  5633 *** General ***
  5634 
  5635 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  5636   Replaces linorder.ML.
  5637 
  5638 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  5639   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  5640   (\<a>...\<z>), are now considered normal letters, and can therefore
  5641   be used anywhere where an ASCII letter (a...zA...Z) has until
  5642   now. COMPATIBILITY: This obviously changes the parsing of some
  5643   terms, especially where a symbol has been used as a binder, say
  5644   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  5645   as an identifier.  Fix it by inserting a space around former
  5646   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  5647   existing theory and ML files.
  5648 
  5649 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  5650 
  5651 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  5652   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  5653   a normal (but invisible) letter. For multiple letter subscripts repeat
  5654   \<^isub> like this: x\<^isub>1\<^isub>2.
  5655 
  5656 * Pure: There are now sub-/superscripts that can span more than one
  5657   character. Text between \<^bsub> and \<^esub> is set in subscript in
  5658   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  5659   superscript. The new control characters are not identifier parts.
  5660 
  5661 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5662   content of "..." to the latex file instead of \isacntrl... . The "..."
  5663   may consist of any printable characters excluding the end bracket >.
  5664 
  5665 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5666   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5667   declare constants "final", which prevents their being given a definition
  5668   later.  It is useful for constants whose behaviour is fixed axiomatically
  5669   rather than definitionally, such as the meta-logic connectives.
  5670 
  5671 * Pure: 'instance' now handles general arities with general sorts
  5672   (i.e. intersections of classes),
  5673 
  5674 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5675   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5676   It can be changed to alter the colors/layout of generated pages.
  5677 
  5678 
  5679 *** Isar ***
  5680 
  5681 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5682   cut_tac, subgoal_tac and thin_tac:
  5683   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5684     locales are no longer forced to write Isar proof scripts.
  5685     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5686     emulations.
  5687   - INCOMPATIBILITY: names of variables to be instantiated may no
  5688     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5689     This is consistent with the instantiation attribute "where".
  5690 
  5691 * Attributes "where" and "of":
  5692   - Now take type variables of instantiated theorem into account when reading
  5693     the instantiation string.  This fixes a bug that caused instantiated
  5694     theorems to have too special types in some circumstances.
  5695   - "where" permits explicit instantiations of type variables.
  5696 
  5697 * Calculation commands "moreover" and "also" no longer interfere with
  5698   current facts ("this"), admitting arbitrary combinations with "then"
  5699   and derived forms.
  5700 
  5701 * Locales:
  5702   - Goal statements involving the context element "includes" no longer
  5703     generate theorems with internal delta predicates (those ending on
  5704     "_axioms") in the premise.
  5705     Resolve particular premise with <locale>.intro to obtain old form.
  5706   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5707     specification and "includes" elements in goal statement.
  5708   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5709     [intro?] and [elim?] (respectively) by default.
  5710   - Experimental command for instantiation of locales in proof contexts:
  5711         instantiate <label>[<attrs>]: <loc>
  5712     Instantiates locale <loc> and adds all its theorems to the current context
  5713     taking into account their attributes.  Label and attrs are optional
  5714     modifiers, like in theorem declarations.  If present, names of
  5715     instantiated theorems are qualified with <label>, and the attributes
  5716     <attrs> are applied after any attributes these theorems might have already.
  5717       If the locale has assumptions, a chained fact of the form
  5718     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5719     are derived.  The command does not support old-style locales declared
  5720     with "locale (open)".
  5721       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5722 
  5723 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5724   (Isar) contexts.
  5725 
  5726 
  5727 *** HOL ***
  5728 
  5729 * Proof import: new image HOL4 contains the imported library from
  5730   the HOL4 system with about 2500 theorems. It is imported by
  5731   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5732   can be used like any other Isabelle image.  See
  5733   HOL/Import/HOL/README for more information.
  5734 
  5735 * Simplifier:
  5736   - Much improved handling of linear and partial orders.
  5737     Reasoners for linear and partial orders are set up for type classes
  5738     "linorder" and "order" respectively, and are added to the default simpset
  5739     as solvers.  This means that the simplifier can build transitivity chains
  5740     to solve goals from the assumptions.
  5741   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5742     of blast or auto after simplification become unnecessary because the goal
  5743     is solved by simplification already.
  5744 
  5745 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5746     all proved in axiomatic type classes for semirings, rings and fields.
  5747 
  5748 * Numerics:
  5749   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5750     now formalized using the Ring_and_Field theory mentioned above.
  5751   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5752     than before, because now they are set up once in a generic manner.
  5753   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5754     Look for the general versions in Ring_and_Field (and Power if they concern
  5755     exponentiation).
  5756 
  5757 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5758 
  5759 * Records:
  5760   - Record types are now by default printed with their type abbreviation
  5761     instead of the list of all field types. This can be configured via
  5762     the reference "print_record_type_abbr".
  5763   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5764     (not enabled by default).
  5765   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5766     EX x. x = sel r to True (not enabled by default).
  5767   - Tactic "record_split_simp_tac" to split and simplify records added.
  5768 
  5769 * 'specification' command added, allowing for definition by
  5770   specification.  There is also an 'ax_specification' command that
  5771   introduces the new constants axiomatically.
  5772 
  5773 * arith(_tac) is now able to generate counterexamples for reals as well.
  5774 
  5775 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5776 
  5777 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5778   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5779 
  5780 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5781   matrix theory to linear programming.
  5782 
  5783 * Unions and Intersections:
  5784   The latex output syntax of UN and INT has been changed
  5785   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5786   i.e. the index formulae has become a subscript.
  5787   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5788 
  5789 * Unions and Intersections over Intervals:
  5790   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5791   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5792   like in normal math, and corresponding versions for < and for intersection.
  5793 
  5794 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5795   lexicographic dictonary ordering has been added as "lexord".
  5796 
  5797 * ML: the legacy theory structures Int and List have been removed. They had
  5798   conflicted with ML Basis Library structures having the same names.
  5799 
  5800 * 'refute' command added to search for (finite) countermodels.  Only works
  5801   for a fragment of HOL.  The installation of an external SAT solver is
  5802   highly recommended.  See "HOL/Refute.thy" for details.
  5803 
  5804 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5805   formulae under an assignment of free variables to random values.
  5806   In contrast to 'refute', it can deal with inductive datatypes,
  5807   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5808   for examples.
  5809 
  5810 
  5811 *** HOLCF ***
  5812 
  5813 * Streams now come with concatenation and are part of the HOLCF image
  5814 
  5815 
  5816 
  5817 New in Isabelle2003 (May 2003)
  5818 ------------------------------
  5819 
  5820 *** General ***
  5821 
  5822 * Provers/simplifier:
  5823 
  5824   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5825     Assumptions are now subject to complete mutual simplification,
  5826     not just from left to right. The simplifier now preserves
  5827     the order of assumptions.
  5828 
  5829     Potential INCOMPATIBILITY:
  5830 
  5831     -- simp sometimes diverges where the old version did
  5832        not, e.g. invoking simp on the goal
  5833 
  5834         [| P (f x); y = x; f x = f y |] ==> Q
  5835 
  5836        now gives rise to the infinite reduction sequence
  5837 
  5838         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5839 
  5840        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5841        kind of problem.
  5842 
  5843     -- Tactics combining classical reasoner and simplification (such as auto)
  5844        are also affected by this change, because many of them rely on
  5845        simp. They may sometimes diverge as well or yield a different numbers
  5846        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5847        in case of problems. Sometimes subsequent calls to the classical
  5848        reasoner will fail because a preceeding call to the simplifier too
  5849        eagerly simplified the goal, e.g. deleted redundant premises.
  5850 
  5851   - The simplifier trace now shows the names of the applied rewrite rules
  5852 
  5853   - You can limit the number of recursive invocations of the simplifier
  5854     during conditional rewriting (where the simplifie tries to solve the
  5855     conditions before applying the rewrite rule):
  5856     ML "simp_depth_limit := n"
  5857     where n is an integer. Thus you can force termination where previously
  5858     the simplifier would diverge.
  5859 
  5860   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5861 
  5862   - No longer aborts on failed congruence proof.  Instead, the
  5863     congruence is ignored.
  5864 
  5865 * Pure: New generic framework for extracting programs from constructive
  5866   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5867   as HOL/Extraction for some case studies.
  5868 
  5869 * Pure: The main goal of the proof state is no longer shown by default, only
  5870 the subgoals. This behaviour is controlled by a new flag.
  5871    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5872 (ML: Proof.show_main_goal).
  5873 
  5874 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5875 rules whose conclusion matches subgoal 1:
  5876       PG menu: Isabelle/Isar -> Show me -> matching rules
  5877 The rules are ordered by how closely they match the subgoal.
  5878 In particular, rules that solve a subgoal outright are displayed first
  5879 (or rather last, the way they are printed).
  5880 (ML: ProofGeneral.print_intros())
  5881 
  5882 * Pure: New flag trace_unify_fail causes unification to print
  5883 diagnostic information (PG: in trace buffer) when it fails. This is
  5884 useful for figuring out why single step proofs like rule, erule or
  5885 assumption failed.
  5886 
  5887 * Pure: Locale specifications now produce predicate definitions
  5888 according to the body of text (covering assumptions modulo local
  5889 definitions); predicate "loc_axioms" covers newly introduced text,
  5890 while "loc" is cumulative wrt. all included locale expressions; the
  5891 latter view is presented only on export into the global theory
  5892 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5893 on the old view without predicates;
  5894 
  5895 * Pure: predefined locales "var" and "struct" are useful for sharing
  5896 parameters (as in CASL, for example); just specify something like
  5897 ``var x + var y + struct M'' as import;
  5898 
  5899 * Pure: improved thms_containing: proper indexing of facts instead of
  5900 raw theorems; check validity of results wrt. current name space;
  5901 include local facts of proof configuration (also covers active
  5902 locales), cover fixed variables in index; may use "_" in term
  5903 specification; an optional limit for the number of printed facts may
  5904 be given (the default is 40);
  5905 
  5906 * Pure: disallow duplicate fact bindings within new-style theory files
  5907 (batch-mode only);
  5908 
  5909 * Provers: improved induct method: assumptions introduced by case
  5910 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5911 the goal statement); "foo" still refers to all facts collectively;
  5912 
  5913 * Provers: the function blast.overloaded has been removed: all constants
  5914 are regarded as potentially overloaded, which improves robustness in exchange
  5915 for slight decrease in efficiency;
  5916 
  5917 * Provers/linorder: New generic prover for transitivity reasoning over
  5918 linear orders.  Note: this prover is not efficient!
  5919 
  5920 * Isar: preview of problems to finish 'show' now produce an error
  5921 rather than just a warning (in interactive mode);
  5922 
  5923 
  5924 *** HOL ***
  5925 
  5926 * arith(_tac)
  5927 
  5928  - Produces a counter example if it cannot prove a goal.
  5929    Note that the counter example may be spurious if the goal is not a formula
  5930    of quantifier-free linear arithmetic.
  5931    In ProofGeneral the counter example appears in the trace buffer.
  5932 
  5933  - Knows about div k and mod k where k is a numeral of type nat or int.
  5934 
  5935  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  5936    linear arithmetic fails. This takes account of quantifiers and divisibility.
  5937    Presburger arithmetic can also be called explicitly via presburger(_tac).
  5938 
  5939 * simp's arithmetic capabilities have been enhanced a bit: it now
  5940 takes ~= in premises into account (by performing a case split);
  5941 
  5942 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  5943 are distributed over a sum of terms;
  5944 
  5945 * New tactic "trans_tac" and method "trans" instantiate
  5946 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  5947 "<=", "<" and "=").
  5948 
  5949 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  5950 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  5951 
  5952 * 'typedef' command has new option "open" to suppress the set
  5953 definition;
  5954 
  5955 * functions Min and Max on finite sets have been introduced (theory
  5956 Finite_Set);
  5957 
  5958 * attribute [symmetric] now works for relations as well; it turns
  5959 (x,y) : R^-1 into (y,x) : R, and vice versa;
  5960 
  5961 * induct over a !!-quantified statement (say !!x1..xn):
  5962   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  5963 
  5964 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  5965 %x. None. Warning: empty_def now refers to the previously hidden definition
  5966 of the empty set.
  5967 
  5968 * Algebra: formalization of classical algebra.  Intended as base for
  5969 any algebraic development in Isabelle.  Currently covers group theory
  5970 (up to Sylow's theorem) and ring theory (Universal Property of
  5971 Univariate Polynomials).  Contributions welcome;
  5972 
  5973 * GroupTheory: deleted, since its material has been moved to Algebra;
  5974 
  5975 * Complex: new directory of the complex numbers with numeric constants,
  5976 nonstandard complex numbers, and some complex analysis, standard and
  5977 nonstandard (Jacques Fleuriot);
  5978 
  5979 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  5980 
  5981 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  5982 Fleuriot);
  5983 
  5984 * Real/HahnBanach: updated and adapted to locales;
  5985 
  5986 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  5987 Gray and Kramer);
  5988 
  5989 * UNITY: added the Meier-Sanders theory of progress sets;
  5990 
  5991 * MicroJava: bytecode verifier and lightweight bytecode verifier
  5992 as abstract algorithms, instantiated to the JVM;
  5993 
  5994 * Bali: Java source language formalization. Type system, operational
  5995 semantics, axiomatic semantics. Supported language features:
  5996 classes, interfaces, objects,virtual methods, static methods,
  5997 static/instance fields, arrays, access modifiers, definite
  5998 assignment, exceptions.
  5999 
  6000 
  6001 *** ZF ***
  6002 
  6003 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  6004 universe, etc.);
  6005 
  6006 * Main ZF: virtually all theories converted to new-style format;
  6007 
  6008 
  6009 *** ML ***
  6010 
  6011 * Pure: Tactic.prove provides sane interface for internal proofs;
  6012 omits the infamous "standard" operation, so this is more appropriate
  6013 than prove_goalw_cterm in many situations (e.g. in simprocs);
  6014 
  6015 * Pure: improved error reporting of simprocs;
  6016 
  6017 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  6018 up simprocs;
  6019 
  6020 
  6021 *** Document preparation ***
  6022 
  6023 * uses \par instead of \\ for line breaks in theory text. This may
  6024 shift some page breaks in large documents. To get the old behaviour
  6025 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  6026 
  6027 * minimized dependencies of isabelle.sty and isabellesym.sty on
  6028 other packages
  6029 
  6030 * \<euro> now needs package babel/greek instead of marvosym (which
  6031 broke \Rightarrow)
  6032 
  6033 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  6034 textcomp package)
  6035 
  6036 
  6037 
  6038 New in Isabelle2002 (March 2002)
  6039 --------------------------------
  6040 
  6041 *** Document preparation ***
  6042 
  6043 * greatly simplified document preparation setup, including more
  6044 graceful interpretation of isatool usedir -i/-d/-D options, and more
  6045 instructive isatool mkdir; users should basically be able to get
  6046 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  6047 users may run a separate document processing stage manually like this:
  6048 "isatool usedir -D output HOL Test && isatool document Test/output";
  6049 
  6050 * theory dependency graph may now be incorporated into documents;
  6051 isatool usedir -g true will produce session_graph.eps/.pdf for use
  6052 with \includegraphics of LaTeX;
  6053 
  6054 * proper spacing of consecutive markup elements, especially text
  6055 blocks after section headings;
  6056 
  6057 * support bold style (for single symbols only), input syntax is like
  6058 this: "\<^bold>\<alpha>" or "\<^bold>A";
  6059 
  6060 * \<bullet> is now output as bold \cdot by default, which looks much
  6061 better in printed text;
  6062 
  6063 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  6064 note that these symbols are currently unavailable in Proof General /
  6065 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  6066 
  6067 * isatool latex no longer depends on changed TEXINPUTS, instead
  6068 isatool document copies the Isabelle style files to the target
  6069 location;
  6070 
  6071 
  6072 *** Isar ***
  6073 
  6074 * Pure/Provers: improved proof by cases and induction;
  6075   - 'case' command admits impromptu naming of parameters (such as
  6076     "case (Suc n)");
  6077   - 'induct' method divinates rule instantiation from the inductive
  6078     claim; no longer requires excessive ?P bindings for proper
  6079     instantiation of cases;
  6080   - 'induct' method properly enumerates all possibilities of set/type
  6081     rules; as a consequence facts may be also passed through *type*
  6082     rules without further ado;
  6083   - 'induct' method now derives symbolic cases from the *rulified*
  6084     rule (before it used to rulify cases stemming from the internal
  6085     atomized version); this means that the context of a non-atomic
  6086     statement becomes is included in the hypothesis, avoiding the
  6087     slightly cumbersome show "PROP ?case" form;
  6088   - 'induct' may now use elim-style induction rules without chaining
  6089     facts, using ``missing'' premises from the goal state; this allows
  6090     rules stemming from inductive sets to be applied in unstructured
  6091     scripts, while still benefitting from proper handling of non-atomic
  6092     statements; NB: major inductive premises need to be put first, all
  6093     the rest of the goal is passed through the induction;
  6094   - 'induct' proper support for mutual induction involving non-atomic
  6095     rule statements (uses the new concept of simultaneous goals, see
  6096     below);
  6097   - append all possible rule selections, but only use the first
  6098     success (no backtracking);
  6099   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  6100   - undeclared rule case names default to numbers 1, 2, 3, ...;
  6101   - added 'print_induct_rules' (covered by help item in recent Proof
  6102     General versions);
  6103   - moved induct/cases attributes to Pure, methods to Provers;
  6104   - generic method setup instantiated for FOL and HOL;
  6105 
  6106 * Pure: support multiple simultaneous goal statements, for example
  6107 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  6108 meta-level mechanism, this acts as if several individual goals had
  6109 been stated separately; in particular common proof methods need to be
  6110 repeated in order to cover all claims; note that a single elimination
  6111 step is *not* sufficient to establish the two conjunctions, so this
  6112 fails:
  6113 
  6114   assume "A & B" then have A and B ..   (*".." fails*)
  6115 
  6116 better use "obtain" in situations as above; alternative refer to
  6117 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  6118 
  6119 * Pure: proper integration with ``locales''; unlike the original
  6120 version by Florian Kammller, Isar locales package high-level proof
  6121 contexts rather than raw logical ones (e.g. we admit to include
  6122 attributes everywhere); operations on locales include merge and
  6123 rename; support for implicit arguments (``structures''); simultaneous
  6124 type-inference over imports and text; see also HOL/ex/Locales.thy for
  6125 some examples;
  6126 
  6127 * Pure: the following commands have been ``localized'', supporting a
  6128 target locale specification "(in name)": 'lemma', 'theorem',
  6129 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  6130 stored both within the locale and at the theory level (exported and
  6131 qualified by the locale name);
  6132 
  6133 * Pure: theory goals may now be specified in ``long'' form, with
  6134 ad-hoc contexts consisting of arbitrary locale elements. for example
  6135 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  6136 definitions may be given, too); the result is a meta-level rule with
  6137 the context elements being discharged in the obvious way;
  6138 
  6139 * Pure: new proof command 'using' allows to augment currently used
  6140 facts after a goal statement ('using' is syntactically analogous to
  6141 'apply', but acts on the goal's facts only); this allows chained facts
  6142 to be separated into parts given before and after a claim, as in
  6143 ``from a and b have C using d and e <proof>'';
  6144 
  6145 * Pure: renamed "antecedent" case to "rule_context";
  6146 
  6147 * Pure: new 'judgment' command records explicit information about the
  6148 object-logic embedding (used by several tools internally); no longer
  6149 use hard-wired "Trueprop";
  6150 
  6151 * Pure: added 'corollary' command;
  6152 
  6153 * Pure: fixed 'token_translation' command;
  6154 
  6155 * Pure: removed obsolete 'exported' attribute;
  6156 
  6157 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  6158 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  6159 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  6160 
  6161 * Pure: method 'atomize' presents local goal premises as object-level
  6162 statements (atomic meta-level propositions); setup controlled via
  6163 rewrite rules declarations of 'atomize' attribute; example
  6164 application: 'induct' method with proper rule statements in improper
  6165 proof *scripts*;
  6166 
  6167 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  6168 now consider the syntactic context of assumptions, giving a better
  6169 chance to get type-inference of the arguments right (this is
  6170 especially important for locales);
  6171 
  6172 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  6173 mode;
  6174 
  6175 * Pure/obtain: the formal conclusion "thesis", being marked as
  6176 ``internal'', may no longer be reference directly in the text;
  6177 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  6178 situations;
  6179 
  6180 * Pure: generic 'sym' attribute which declares a rule both as pure
  6181 'elim?' and for the 'symmetric' operation;
  6182 
  6183 * Pure: marginal comments ``--'' may now occur just anywhere in the
  6184 text; the fixed correlation with particular command syntax has been
  6185 discontinued;
  6186 
  6187 * Pure: new method 'rules' is particularly well-suited for proof
  6188 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  6189 but often produces more compact proof terms with less detours;
  6190 
  6191 * Pure/Provers/classical: simplified integration with pure rule
  6192 attributes and methods; the classical "intro?/elim?/dest?"
  6193 declarations coincide with the pure ones; the "rule" method no longer
  6194 includes classically swapped intros; "intro" and "elim" methods no
  6195 longer pick rules from the context; also got rid of ML declarations
  6196 AddXIs/AddXEs/AddXDs; all of this has some potential for
  6197 INCOMPATIBILITY;
  6198 
  6199 * Provers/classical: attribute 'swapped' produces classical inversions
  6200 of introduction rules;
  6201 
  6202 * Provers/simplifier: 'simplified' attribute may refer to explicit
  6203 rules instead of full simplifier context; 'iff' attribute handles
  6204 conditional rules;
  6205 
  6206 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  6207 
  6208 * HOL: 'recdef' now fails on unfinished automated proofs, use
  6209 "(permissive)" option to recover old behavior;
  6210 
  6211 * HOL: 'inductive' no longer features separate (collective) attributes
  6212 for 'intros' (was found too confusing);
  6213 
  6214 * HOL: properly declared induction rules less_induct and
  6215 wf_induct_rule;
  6216 
  6217 
  6218 *** HOL ***
  6219 
  6220 * HOL: moved over to sane numeral syntax; the new policy is as
  6221 follows:
  6222 
  6223   - 0 and 1 are polymorphic constants, which are defined on any
  6224   numeric type (nat, int, real etc.);
  6225 
  6226   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  6227   binary representation internally;
  6228 
  6229   - type nat has special constructor Suc, and generally prefers Suc 0
  6230   over 1::nat and Suc (Suc 0) over 2::nat;
  6231 
  6232 This change may cause significant problems of INCOMPATIBILITY; her