NEWS
author haftmann
Sun Jul 17 20:57:56 2011 +0200 (2011-07-17)
changeset 43872 6b917e5877d2
parent 43865 db18f4d0cc7d
child 43873 8a2f339641c1
permissions -rw-r--r--
more consistent theorem names
     1 Isabelle NEWS -- history user-relevant changes
     2 ==============================================
     3 
     4 New in this Isabelle version
     5 ----------------------------
     6 
     7 *** General ***
     8 
     9 * Theory loader: source files are identified by content via SHA1
    10 digests.  Discontinued former path/modtime identification and optional
    11 ISABELLE_FILE_IDENT plugin scripts.
    12 
    13 * Parallelization of nested Isar proofs is subject to
    14 Goal.parallel_proofs_threshold (default 100).  See also isabelle
    15 usedir option -Q.
    16 
    17 * Discontinued support for Poly/ML 5.2, which was the last version
    18 without proper multithreading and TimeLimit implementation.
    19 
    20 * Discontinued old lib/scripts/polyml-platform, which has been
    21 obsolete since Isabelle2009-2.
    22 
    23 * Theory loader: source files are exclusively located via the master
    24 directory of each theory node (where the .thy file itself resides).
    25 The global load path (such as src/HOL/Library) has been discontinued.
    26 Note that the path element ~~ may be used to reference theories in the
    27 Isabelle home folder -- for instance, "~~/src/HOL/Library/FuncSet".
    28 INCOMPATIBILITY.
    29 
    30 * Various optional external tools are referenced more robustly and
    31 uniformly by explicit Isabelle settings as follows:
    32 
    33   ISABELLE_CSDP   (formerly CSDP_EXE)
    34   ISABELLE_GHC    (formerly EXEC_GHC or GHC_PATH)
    35   ISABELLE_OCAML  (formerly EXEC_OCAML)
    36   ISABELLE_SWIPL  (formerly EXEC_SWIPL)
    37   ISABELLE_YAP    (formerly EXEC_YAP)
    38 
    39 Note that automated detection from the file-system or search path has
    40 been discontinued.  INCOMPATIBILITY.
    41 
    42 * Name space: former unsynchronized references are now proper
    43 configuration options, with more conventional names:
    44 
    45   long_names   ~> names_long
    46   short_names  ~> names_short
    47   unique_names ~> names_unique
    48 
    49 Minor INCOMPATIBILITY, need to declare options in context like this:
    50 
    51   declare [[names_unique = false]]
    52 
    53 * Literal facts `prop` may contain dummy patterns, e.g. `_ = _`.  Note
    54 that the result needs to be unique, which means fact specifications
    55 may have to be refined after enriching a proof context.
    56 
    57 * Isabelle/Isar reference manual provides more formal references in
    58 syntax diagrams.
    59 
    60 
    61 *** HOL ***
    62 
    63 * Classes bot and top require underlying partial order rather than preorder:
    64 uniqueness of bot and top is guaranteed.  INCOMPATIBILITY.
    65 
    66 * Class 'complete_lattice': generalized a couple of lemmas from sets;
    67 generalized theorems INF_cong and SUP_cong.  More consistent and less
    68 misunderstandable names:
    69   INFI_def ~> INF_def
    70   SUPR_def ~> SUP_def
    71   le_SUPI ~> le_SUP_I
    72   le_SUPI2 ~> le_SUP_I2
    73   le_INFI ~> le_INF_I
    74 INCOMPATIBILITY.
    75 
    76 * Archimedian_Field.thy:
    77     floor now is defined as parameter of a separate type class floor_ceiling.
    78  
    79 * Finite_Set.thy: more coherent development of fold_set locales:
    80 
    81     locale fun_left_comm ~> locale comp_fun_commute
    82     locale fun_left_comm_idem ~> locale comp_fun_idem
    83     
    84 Both use point-free characterisation; interpretation proofs may need adjustment.
    85 INCOMPATIBILITY.
    86 
    87 * Code generation:
    88   - theory Library/Code_Char_ord provides native ordering of characters
    89     in the target language.
    90     
    91 * Declare ext [intro] by default.  Rare INCOMPATIBILITY.
    92 
    93 * Nitpick:
    94   - Added "need" and "total_consts" options.
    95   - Reintroduced "show_skolems" option by popular demand.
    96   - Renamed attribute: nitpick_def ~> nitpick_unfold.
    97     INCOMPATIBILITY.
    98 
    99 * Sledgehammer:
   100   - sledgehammer available_provers ~> sledgehammer supported_provers.
   101     INCOMPATIBILITY.
   102   - Added support for SNARK and ToFoF-E on SystemOnTPTP and for simply typed
   103     TPTP problems (TFF).
   104   - Added "preplay_timeout", "slicing", "type_enc", "sound", "max_mono_iters",
   105     and "max_new_mono_instances" options.
   106   - Removed "explicit_apply" and "full_types" options as well as "Full Types"
   107     Proof General menu item. INCOMPATIBILITY.
   108 
   109 * Metis:
   110   - Removed "metisF" -- use "metis" instead. INCOMPATIBILITY.
   111   - Obsoleted "metisFT" -- use "metis (full_types)" instead. INCOMPATIBILITY.
   112 
   113 * "try":
   114   - Renamed "try_methods" and added "simp:", "intro:", "dest:", and "elim:"
   115     options. INCOMPATIBILITY.
   116   - Introduced "try" that not only runs "try_methods" but also "solve_direct",
   117     "sledgehammer", "quickcheck", and "nitpick".
   118 
   119 * Quickcheck:
   120   - Added "eval" option to evaluate terms for the found counterexample
   121     (currently only supported by the default (exhaustive) tester)
   122   - Added post-processing of terms to obtain readable counterexamples
   123     (currently only supported by the default (exhaustive) tester)
   124   - New counterexample generator quickcheck[narrowing] enables
   125     narrowing-based testing.
   126     It requires that the Glasgow Haskell compiler is installed and
   127     its location is known to Isabelle with the environment variable
   128     ISABELLE_GHC.
   129 
   130 * Function package: discontinued option "tailrec".
   131 INCOMPATIBILITY. Use partial_function instead.
   132 
   133 * HOL-Probability:
   134   - Caratheodory's extension lemma is now proved for ring_of_sets.
   135   - Infinite products of probability measures are now available.
   136   - Use extended reals instead of positive extended reals.
   137     INCOMPATIBILITY.
   138 
   139 
   140 *** Document preparation ***
   141 
   142 * Discontinued special treatment of hard tabulators, which are better
   143 avoided in the first place.  Implicit tab-width is 1.
   144 
   145 * Antiquotation @{rail} layouts railroad syntax diagrams, see also
   146 isar-ref manual.
   147 
   148 * Antiquotation @{value} evaluates the given term and presents its result.
   149 
   150 * Localized \isabellestyle switch can be used within blocks or groups
   151 like this:
   152 
   153   \isabellestyle{it}  %preferred default
   154   {\isabellestylett @{text "typewriter stuff"}}
   155 
   156 * New term style "isub" as ad-hoc conversion of variables x1, y23 into
   157 subscripted form x\<^isub>1, y\<^isub>2\<^isub>3.
   158 
   159 * Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
   160 (e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).
   161 
   162 
   163 *** ML ***
   164 
   165 * The inner syntax of sort/type/term/prop supports inlined YXML
   166 representations within quoted string tokens.  By encoding logical
   167 entities via Term_XML (in ML or Scala) concrete syntax can be
   168 bypassed, which is particularly useful for producing bits of text
   169 under external program control.
   170 
   171 * Antiquotations for ML and document preparation are managed as theory
   172 data, which requires explicit setup.
   173 
   174 * Isabelle_Process.is_active allows tools to check if the official
   175 process wrapper is running (Isabelle/Scala/jEdit) or the old TTY loop
   176 (better known as Proof General).
   177 
   178 * Structure Proof_Context follows standard naming scheme.  Old
   179 ProofContext is still available for some time as legacy alias.
   180 
   181 * Structure Timing provides various operations for timing; supersedes
   182 former start_timing/end_timing etc.
   183 
   184 * Path.print is the official way to show file-system paths to users
   185 (including quotes etc.).
   186 
   187 * Inner syntax: identifiers in parse trees of generic categories
   188 "logic", "aprop", "idt" etc. carry position information (disguised as
   189 type constraints).  Occasional INCOMPATIBILITY with non-compliant
   190 translations that choke on unexpected type constraints.  Positions can
   191 be stripped in ML translations via Syntax.strip_positions /
   192 Syntax.strip_positions_ast, or via the syntax constant
   193 "_strip_positions" within parse trees.  As last resort, positions can
   194 be disabled via the configuration option Syntax.positions, which is
   195 called "syntax_positions" in Isar attribute syntax.
   196 
   197 * Discontinued special status of various ML structures that contribute
   198 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
   199 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
   200 refer directly to Ast.Constant, Lexicon.is_identifier,
   201 Syntax_Trans.mk_binder_tr etc.
   202 
   203 * Typed print translation: discontinued show_sorts argument, which is
   204 already available via context of "advanced" translation.
   205 
   206 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
   207 goal states; body tactic needs to address all subgoals uniformly.
   208 
   209 * Slightly more special eq_list/eq_set, with shortcut involving
   210 pointer equality (assumes that eq relation is reflexive).
   211 
   212 * Classical tactics use proper Proof.context instead of historic types
   213 claset/clasimpset.  Old-style declarations like addIs, addEs, addDs
   214 operate directly on Proof.context.  Raw type claset retains its use as
   215 snapshot of the classical context, which can be recovered via
   216 (put_claset HOL_cs) etc.  Type clasimpset has been discontinued.
   217 INCOMPATIBILITY, classical tactics and derived proof methods require
   218 proper Proof.context.
   219 
   220 * Scala layer provides JVM method invocation service for static
   221 methods of type (String)String, see Invoke_Scala.method in ML.
   222 For example:
   223 
   224   Invoke_Scala.method "java.lang.System.getProperty" "java.home"
   225 
   226 
   227 
   228 New in Isabelle2011 (January 2011)
   229 ----------------------------------
   230 
   231 *** General ***
   232 
   233 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
   234 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
   235 useful tooltips and hyperlinks produced from its static analysis.  The
   236 bundled component provides an executable Isabelle tool that can be run
   237 like this:
   238 
   239   Isabelle2011/bin/isabelle jedit
   240 
   241 * Significantly improved Isabelle/Isar implementation manual.
   242 
   243 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
   244 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
   245 while the default heap location within that directory lacks that extra
   246 suffix.  This isolates multiple Isabelle installations from each
   247 other, avoiding problems with old settings in new versions.
   248 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
   249 
   250 * Source files are always encoded as UTF-8, instead of old-fashioned
   251 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
   252 the following package declarations:
   253 
   254   \usepackage[utf8]{inputenc}
   255   \usepackage{textcomp}
   256 
   257 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
   258 a Unicode character is treated as a single symbol, not a sequence of
   259 non-ASCII bytes as before.  Since Isabelle/ML string literals may
   260 contain symbols without further backslash escapes, Unicode can now be
   261 used here as well.  Recall that Symbol.explode in ML provides a
   262 consistent view on symbols, while raw explode (or String.explode)
   263 merely give a byte-oriented representation.
   264 
   265 * Theory loader: source files are primarily located via the master
   266 directory of each theory node (where the .thy file itself resides).
   267 The global load path is still partially available as legacy feature.
   268 Minor INCOMPATIBILITY due to subtle change in file lookup: use
   269 explicit paths, relatively to the theory.
   270 
   271 * Special treatment of ML file names has been discontinued.
   272 Historically, optional extensions .ML or .sml were added on demand --
   273 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
   274 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
   275 
   276 * Various options that affect pretty printing etc. are now properly
   277 handled within the context via configuration options, instead of
   278 unsynchronized references or print modes.  There are both ML Config.T
   279 entities and Isar declaration attributes to access these.
   280 
   281   ML (Config.T)                 Isar (attribute)
   282 
   283   eta_contract                  eta_contract
   284   show_brackets                 show_brackets
   285   show_sorts                    show_sorts
   286   show_types                    show_types
   287   show_question_marks           show_question_marks
   288   show_consts                   show_consts
   289   show_abbrevs                  show_abbrevs
   290 
   291   Syntax.ast_trace              syntax_ast_trace
   292   Syntax.ast_stat               syntax_ast_stat
   293   Syntax.ambiguity_level        syntax_ambiguity_level
   294 
   295   Goal_Display.goals_limit      goals_limit
   296   Goal_Display.show_main_goal   show_main_goal
   297 
   298   Method.rule_trace             rule_trace
   299 
   300   Thy_Output.display            thy_output_display
   301   Thy_Output.quotes             thy_output_quotes
   302   Thy_Output.indent             thy_output_indent
   303   Thy_Output.source             thy_output_source
   304   Thy_Output.break              thy_output_break
   305 
   306 Note that corresponding "..._default" references in ML may only be
   307 changed globally at the ROOT session setup, but *not* within a theory.
   308 The option "show_abbrevs" supersedes the former print mode
   309 "no_abbrevs" with inverted meaning.
   310 
   311 * More systematic naming of some configuration options.
   312 INCOMPATIBILITY.
   313 
   314   trace_simp  ~>  simp_trace
   315   debug_simp  ~>  simp_debug
   316 
   317 * Support for real valued configuration options, using simplistic
   318 floating-point notation that coincides with the inner syntax for
   319 float_token.
   320 
   321 * Support for real valued preferences (with approximative PGIP type):
   322 front-ends need to accept "pgint" values in float notation.
   323 INCOMPATIBILITY.
   324 
   325 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
   326 DejaVu Sans.
   327 
   328 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   329 
   330 
   331 *** Pure ***
   332 
   333 * Command 'type_synonym' (with single argument) replaces somewhat
   334 outdated 'types', which is still available as legacy feature for some
   335 time.
   336 
   337 * Command 'nonterminal' (with 'and' separated list of arguments)
   338 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
   339 
   340 * Command 'notepad' replaces former 'example_proof' for
   341 experimentation in Isar without any result.  INCOMPATIBILITY.
   342 
   343 * Locale interpretation commands 'interpret' and 'sublocale' accept
   344 lists of equations to map definitions in a locale to appropriate
   345 entities in the context of the interpretation.  The 'interpretation'
   346 command already provided this functionality.
   347 
   348 * Diagnostic command 'print_dependencies' prints the locale instances
   349 that would be activated if the specified expression was interpreted in
   350 the current context.  Variant "print_dependencies!" assumes a context
   351 without interpretations.
   352 
   353 * Diagnostic command 'print_interps' prints interpretations in proofs
   354 in addition to interpretations in theories.
   355 
   356 * Discontinued obsolete 'global' and 'local' commands to manipulate
   357 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
   358 Sign.root_path and Sign.local_path may be applied directly where this
   359 feature is still required for historical reasons.
   360 
   361 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
   362 'definition' instead.
   363 
   364 * The "prems" fact, which refers to the accidental collection of
   365 foundational premises in the context, is now explicitly marked as
   366 legacy feature and will be discontinued soon.  Consider using "assms"
   367 of the head statement or reference facts by explicit names.
   368 
   369 * Document antiquotations @{class} and @{type} print classes and type
   370 constructors.
   371 
   372 * Document antiquotation @{file} checks file/directory entries within
   373 the local file system.
   374 
   375 
   376 *** HOL ***
   377 
   378 * Coercive subtyping: functions can be declared as coercions and type
   379 inference will add them as necessary upon input of a term.  Theory
   380 Complex_Main declares real :: nat => real and real :: int => real as
   381 coercions. A coercion function f is declared like this:
   382 
   383   declare [[coercion f]]
   384 
   385 To lift coercions through type constructors (e.g. from nat => real to
   386 nat list => real list), map functions can be declared, e.g.
   387 
   388   declare [[coercion_map map]]
   389 
   390 Currently coercion inference is activated only in theories including
   391 real numbers, i.e. descendants of Complex_Main.  This is controlled by
   392 the configuration option "coercion_enabled", e.g. it can be enabled in
   393 other theories like this:
   394 
   395   declare [[coercion_enabled]]
   396 
   397 * Command 'partial_function' provides basic support for recursive
   398 function definitions over complete partial orders.  Concrete instances
   399 are provided for i) the option type, ii) tail recursion on arbitrary
   400 types, and iii) the heap monad of Imperative_HOL.  See
   401 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
   402 for examples.
   403 
   404 * Function package: f.psimps rules are no longer implicitly declared
   405 as [simp].  INCOMPATIBILITY.
   406 
   407 * Datatype package: theorems generated for executable equality (class
   408 "eq") carry proper names and are treated as default code equations.
   409 
   410 * Inductive package: now offers command 'inductive_simps' to
   411 automatically derive instantiated and simplified equations for
   412 inductive predicates, similar to 'inductive_cases'.
   413 
   414 * Command 'enriched_type' allows to register properties of the
   415 functorial structure of types.
   416 
   417 * Improved infrastructure for term evaluation using code generator
   418 techniques, in particular static evaluation conversions.
   419 
   420 * Code generator: Scala (2.8 or higher) has been added to the target
   421 languages.
   422 
   423 * Code generator: globbing constant expressions "*" and "Theory.*"
   424 have been replaced by the more idiomatic "_" and "Theory._".
   425 INCOMPATIBILITY.
   426 
   427 * Code generator: export_code without explicit file declaration prints
   428 to standard output.  INCOMPATIBILITY.
   429 
   430 * Code generator: do not print function definitions for case
   431 combinators any longer.
   432 
   433 * Code generator: simplification with rules determined with
   434 src/Tools/Code/code_simp.ML and method "code_simp".
   435 
   436 * Code generator for records: more idiomatic representation of record
   437 types.  Warning: records are not covered by ancient SML code
   438 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
   439 rep_datatype declaration helps to succeed then:
   440 
   441   record 'a foo = ...
   442   ...
   443   rep_datatype foo_ext ...
   444 
   445 * Records: logical foundation type for records does not carry a
   446 '_type' suffix any longer (obsolete due to authentic syntax).
   447 INCOMPATIBILITY.
   448 
   449 * Quickcheck now by default uses exhaustive testing instead of random
   450 testing.  Random testing can be invoked by "quickcheck [random]",
   451 exhaustive testing by "quickcheck [exhaustive]".
   452 
   453 * Quickcheck instantiates polymorphic types with small finite
   454 datatypes by default. This enables a simple execution mechanism to
   455 handle quantifiers and function equality over the finite datatypes.
   456 
   457 * Quickcheck random generator has been renamed from "code" to
   458 "random".  INCOMPATIBILITY.
   459 
   460 * Quickcheck now has a configurable time limit which is set to 30
   461 seconds by default. This can be changed by adding [timeout = n] to the
   462 quickcheck command. The time limit for Auto Quickcheck is still set
   463 independently.
   464 
   465 * Quickcheck in locales considers interpretations of that locale for
   466 counter example search.
   467 
   468 * Sledgehammer:
   469   - Added "smt" and "remote_smt" provers based on the "smt" proof
   470     method. See the Sledgehammer manual for details ("isabelle doc
   471     sledgehammer").
   472   - Renamed commands:
   473     sledgehammer atp_info ~> sledgehammer running_provers
   474     sledgehammer atp_kill ~> sledgehammer kill_provers
   475     sledgehammer available_atps ~> sledgehammer available_provers
   476     INCOMPATIBILITY.
   477   - Renamed options:
   478     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
   479     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
   480     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
   481     (and "ms" and "min" are no longer supported)
   482     INCOMPATIBILITY.
   483 
   484 * Nitpick:
   485   - Renamed options:
   486     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
   487     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
   488     INCOMPATIBILITY.
   489   - Added support for partial quotient types.
   490   - Added local versions of the "Nitpick.register_xxx" functions.
   491   - Added "whack" option.
   492   - Allow registration of quotient types as codatatypes.
   493   - Improved "merge_type_vars" option to merge more types.
   494   - Removed unsound "fast_descrs" option.
   495   - Added custom symmetry breaking for datatypes, making it possible to reach
   496     higher cardinalities.
   497   - Prevent the expansion of too large definitions.
   498 
   499 * Proof methods "metis" and "meson" now have configuration options
   500 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
   501 to diagnose these tools. E.g.
   502 
   503     using [[metis_trace = true]]
   504 
   505 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
   506 manually as command 'solve_direct'.
   507 
   508 * The default SMT solver Z3 must be enabled explicitly (due to
   509 licensing issues) by setting the environment variable
   510 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
   511 commercial applications, the SMT solver CVC3 is provided as fall-back;
   512 changing the SMT solver is done via the configuration option
   513 "smt_solver".
   514 
   515 * Remote SMT solvers need to be referred to by the "remote_" prefix,
   516 i.e. "remote_cvc3" and "remote_z3".
   517 
   518 * Added basic SMT support for datatypes, records, and typedefs using
   519 the oracle mode (no proofs).  Direct support of pairs has been dropped
   520 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
   521 support for a similar behavior).  Minor INCOMPATIBILITY.
   522 
   523 * Changed SMT configuration options:
   524   - Renamed:
   525     z3_proofs ~> smt_oracle (with inverted meaning)
   526     z3_trace_assms ~> smt_trace_used_facts
   527     INCOMPATIBILITY.
   528   - Added:
   529     smt_verbose
   530     smt_random_seed
   531     smt_datatypes
   532     smt_infer_triggers
   533     smt_monomorph_limit
   534     cvc3_options
   535     remote_cvc3_options
   536     remote_z3_options
   537     yices_options
   538 
   539 * Boogie output files (.b2i files) need to be declared in the theory
   540 header.
   541 
   542 * Simplification procedure "list_to_set_comprehension" rewrites list
   543 comprehensions applied to List.set to set comprehensions.  Occasional
   544 INCOMPATIBILITY, may be deactivated like this:
   545 
   546   declare [[simproc del: list_to_set_comprehension]]
   547 
   548 * Removed old version of primrec package.  INCOMPATIBILITY.
   549 
   550 * Removed simplifier congruence rule of "prod_case", as has for long
   551 been the case with "split".  INCOMPATIBILITY.
   552 
   553 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
   554 
   555 * Removed [split_format ... and ... and ...] version of
   556 [split_format].  Potential INCOMPATIBILITY.
   557 
   558 * Predicate "sorted" now defined inductively, with nice induction
   559 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
   560 
   561 * Constant "contents" renamed to "the_elem", to free the generic name
   562 contents for other uses.  INCOMPATIBILITY.
   563 
   564 * Renamed class eq and constant eq (for code generation) to class
   565 equal and constant equal, plus renaming of related facts and various
   566 tuning.  INCOMPATIBILITY.
   567 
   568 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
   569 
   570 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
   571 INCOMPATIBILITY.
   572 
   573 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
   574 avoid confusion with finite sets.  INCOMPATIBILITY.
   575 
   576 * Abandoned locales equiv, congruent and congruent2 for equivalence
   577 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
   578 for congruent(2)).
   579 
   580 * Some previously unqualified names have been qualified:
   581 
   582   types
   583     bool ~> HOL.bool
   584     nat ~> Nat.nat
   585 
   586   constants
   587     Trueprop ~> HOL.Trueprop
   588     True ~> HOL.True
   589     False ~> HOL.False
   590     op & ~> HOL.conj
   591     op | ~> HOL.disj
   592     op --> ~> HOL.implies
   593     op = ~> HOL.eq
   594     Not ~> HOL.Not
   595     The ~> HOL.The
   596     All ~> HOL.All
   597     Ex ~> HOL.Ex
   598     Ex1 ~> HOL.Ex1
   599     Let ~> HOL.Let
   600     If ~> HOL.If
   601     Ball ~> Set.Ball
   602     Bex ~> Set.Bex
   603     Suc ~> Nat.Suc
   604     Pair ~> Product_Type.Pair
   605     fst ~> Product_Type.fst
   606     snd ~> Product_Type.snd
   607     curry ~> Product_Type.curry
   608     op : ~> Set.member
   609     Collect ~> Set.Collect
   610 
   611 INCOMPATIBILITY.
   612 
   613 * More canonical naming convention for some fundamental definitions:
   614 
   615     bot_bool_eq ~> bot_bool_def
   616     top_bool_eq ~> top_bool_def
   617     inf_bool_eq ~> inf_bool_def
   618     sup_bool_eq ~> sup_bool_def
   619     bot_fun_eq  ~> bot_fun_def
   620     top_fun_eq  ~> top_fun_def
   621     inf_fun_eq  ~> inf_fun_def
   622     sup_fun_eq  ~> sup_fun_def
   623 
   624 INCOMPATIBILITY.
   625 
   626 * More stylized fact names:
   627 
   628   expand_fun_eq ~> fun_eq_iff
   629   expand_set_eq ~> set_eq_iff
   630   set_ext       ~> set_eqI
   631   nat_number    ~> eval_nat_numeral
   632 
   633 INCOMPATIBILITY.
   634 
   635 * Refactoring of code-generation specific operations in theory List:
   636 
   637   constants
   638     null ~> List.null
   639 
   640   facts
   641     mem_iff ~> member_def
   642     null_empty ~> null_def
   643 
   644 INCOMPATIBILITY.  Note that these were not supposed to be used
   645 regularly unless for striking reasons; their main purpose was code
   646 generation.
   647 
   648 Various operations from the Haskell prelude are used for generating
   649 Haskell code.
   650 
   651 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
   652 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
   653 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
   654 
   655 * Abolished some non-alphabetic type names: "prod" and "sum" replace
   656 "*" and "+" respectively.  INCOMPATIBILITY.
   657 
   658 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
   659 "Sum_Type.Plus" instead.
   660 
   661 * Constant "split" has been merged with constant "prod_case"; names of
   662 ML functions, facts etc. involving split have been retained so far,
   663 though.  INCOMPATIBILITY.
   664 
   665 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
   666 instead.  INCOMPATIBILITY.
   667 
   668 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
   669 INCOMPATIBILITY.
   670 
   671 * Former theory Library/Enum is now part of the HOL-Main image.
   672 INCOMPATIBILITY: all constants of the Enum theory now have to be
   673 referred to by its qualified name.
   674 
   675   enum    ~>  Enum.enum
   676   nlists  ~>  Enum.nlists
   677   product ~>  Enum.product
   678 
   679 * Theory Library/Monad_Syntax provides do-syntax for monad types.
   680 Syntax in Library/State_Monad has been changed to avoid ambiguities.
   681 INCOMPATIBILITY.
   682 
   683 * Theory Library/SetsAndFunctions has been split into
   684 Library/Function_Algebras and Library/Set_Algebras; canonical names
   685 for instance definitions for functions; various improvements.
   686 INCOMPATIBILITY.
   687 
   688 * Theory Library/Multiset provides stable quicksort implementation of
   689 sort_key.
   690 
   691 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
   692 INCOMPATIBILITY.
   693 
   694 * Session Multivariate_Analysis: introduced a type class for euclidean
   695 space.  Most theorems are now stated in terms of euclidean spaces
   696 instead of finite cartesian products.
   697 
   698   types
   699     real ^ 'n ~>  'a::real_vector
   700               ~>  'a::euclidean_space
   701               ~>  'a::ordered_euclidean_space
   702         (depends on your needs)
   703 
   704   constants
   705      _ $ _        ~> _ $$ _
   706      \<chi> x. _  ~> \<chi>\<chi> x. _
   707      CARD('n)     ~> DIM('a)
   708 
   709 Also note that the indices are now natural numbers and not from some
   710 finite type. Finite cartesian products of euclidean spaces, products
   711 of euclidean spaces the real and complex numbers are instantiated to
   712 be euclidean_spaces.  INCOMPATIBILITY.
   713 
   714 * Session Probability: introduced pextreal as positive extended real
   715 numbers.  Use pextreal as value for measures.  Introduce the
   716 Radon-Nikodym derivative, product spaces and Fubini's theorem for
   717 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
   718 the integral in Multivariate Analysis.  INCOMPATIBILITY.
   719 
   720 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   721 INCOMPATIBILITY.
   722 
   723 * Session SPARK (with image HOL-SPARK) provides commands to load and
   724 prove verification conditions generated by the SPARK Ada program
   725 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
   726 
   727 
   728 *** HOL-Algebra ***
   729 
   730 * Theorems for additive ring operations (locale abelian_monoid and
   731 descendants) are generated by interpretation from their multiplicative
   732 counterparts.  Names (in particular theorem names) have the mandatory
   733 qualifier 'add'.  Previous theorem names are redeclared for
   734 compatibility.
   735 
   736 * Structure "int_ring" is now an abbreviation (previously a
   737 definition).  This fits more natural with advanced interpretations.
   738 
   739 
   740 *** HOLCF ***
   741 
   742 * The domain package now runs in definitional mode by default: The
   743 former command 'new_domain' is now called 'domain'.  To use the domain
   744 package in its original axiomatic mode, use 'domain (unsafe)'.
   745 INCOMPATIBILITY.
   746 
   747 * The new class "domain" is now the default sort.  Class "predomain"
   748 is an unpointed version of "domain". Theories can be updated by
   749 replacing sort annotations as shown below.  INCOMPATIBILITY.
   750 
   751   'a::type ~> 'a::countable
   752   'a::cpo  ~> 'a::predomain
   753   'a::pcpo ~> 'a::domain
   754 
   755 * The old type class "rep" has been superseded by class "domain".
   756 Accordingly, users of the definitional package must remove any
   757 "default_sort rep" declarations.  INCOMPATIBILITY.
   758 
   759 * The domain package (definitional mode) now supports unpointed
   760 predomain argument types, as long as they are marked 'lazy'. (Strict
   761 arguments must be in class "domain".) For example, the following
   762 domain definition now works:
   763 
   764   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
   765 
   766 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
   767 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
   768 'a option, and 'a list.  Additionally, it configures fixrec and the
   769 domain package to work with these types.  For example:
   770 
   771   fixrec isInl :: "('a + 'b) u -> tr"
   772     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
   773 
   774   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
   775 
   776 * The "(permissive)" option of fixrec has been replaced with a
   777 per-equation "(unchecked)" option. See
   778 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
   779 
   780 * The "bifinite" class no longer fixes a constant "approx"; the class
   781 now just asserts that such a function exists.  INCOMPATIBILITY.
   782 
   783 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
   784 defines an embedding of type 'a defl into udom by default; instances
   785 of "bifinite" and "domain" classes are available in
   786 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
   787 
   788 * The syntax "REP('a)" has been replaced with "DEFL('a)".
   789 
   790 * The predicate "directed" has been removed.  INCOMPATIBILITY.
   791 
   792 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
   793 
   794 * The function "cprod_map" has been renamed to "prod_map".
   795 INCOMPATIBILITY.
   796 
   797 * The monadic bind operator on each powerdomain has new binder syntax
   798 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
   799 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
   800 
   801 * The infix syntax for binary union on each powerdomain has changed
   802 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
   803 syntax.  INCOMPATIBILITY.
   804 
   805 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
   806 still supported as an input translation.
   807 
   808 * Renamed some theorems (the original names are also still available).
   809 
   810   expand_fun_below   ~> fun_below_iff
   811   below_fun_ext      ~> fun_belowI
   812   expand_cfun_eq     ~> cfun_eq_iff
   813   ext_cfun           ~> cfun_eqI
   814   expand_cfun_below  ~> cfun_below_iff
   815   below_cfun_ext     ~> cfun_belowI
   816   cont2cont_Rep_CFun ~> cont2cont_APP
   817 
   818 * The Abs and Rep functions for various types have changed names.
   819 Related theorem names have also changed to match. INCOMPATIBILITY.
   820 
   821   Rep_CFun  ~> Rep_cfun
   822   Abs_CFun  ~> Abs_cfun
   823   Rep_Sprod ~> Rep_sprod
   824   Abs_Sprod ~> Abs_sprod
   825   Rep_Ssum  ~> Rep_ssum
   826   Abs_Ssum  ~> Abs_ssum
   827 
   828 * Lemmas with names of the form *_defined_iff or *_strict_iff have
   829 been renamed to *_bottom_iff.  INCOMPATIBILITY.
   830 
   831 * Various changes to bisimulation/coinduction with domain package:
   832 
   833   - Definitions of "bisim" constants no longer mention definedness.
   834   - With mutual recursion, "bisim" predicate is now curried.
   835   - With mutual recursion, each type gets a separate coind theorem.
   836   - Variable names in bisim_def and coinduct rules have changed.
   837 
   838 INCOMPATIBILITY.
   839 
   840 * Case combinators generated by the domain package for type "foo" are
   841 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
   842 
   843 * Several theorems have been renamed to more accurately reflect the
   844 names of constants and types involved.  INCOMPATIBILITY.
   845 
   846   thelub_const    ~> lub_const
   847   lub_const       ~> is_lub_const
   848   thelubI         ~> lub_eqI
   849   is_lub_lub      ~> is_lubD2
   850   lubI            ~> is_lub_lub
   851   unique_lub      ~> is_lub_unique
   852   is_ub_lub       ~> is_lub_rangeD1
   853   lub_bin_chain   ~> is_lub_bin_chain
   854   lub_fun         ~> is_lub_fun
   855   thelub_fun      ~> lub_fun
   856   thelub_cfun     ~> lub_cfun
   857   thelub_Pair     ~> lub_Pair
   858   lub_cprod       ~> is_lub_prod
   859   thelub_cprod    ~> lub_prod
   860   minimal_cprod   ~> minimal_prod
   861   inst_cprod_pcpo ~> inst_prod_pcpo
   862   UU_I            ~> bottomI
   863   compact_UU      ~> compact_bottom
   864   deflation_UU    ~> deflation_bottom
   865   finite_deflation_UU ~> finite_deflation_bottom
   866 
   867 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
   868 
   869   sq_ord_less_eq_trans ~> below_eq_trans
   870   sq_ord_eq_less_trans ~> eq_below_trans
   871   refl_less            ~> below_refl
   872   trans_less           ~> below_trans
   873   antisym_less         ~> below_antisym
   874   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
   875   box_less             ~> box_below
   876   rev_trans_less       ~> rev_below_trans
   877   not_less2not_eq      ~> not_below2not_eq
   878   less_UU_iff          ~> below_UU_iff
   879   flat_less_iff        ~> flat_below_iff
   880   adm_less             ~> adm_below
   881   adm_not_less         ~> adm_not_below
   882   adm_compact_not_less ~> adm_compact_not_below
   883   less_fun_def         ~> below_fun_def
   884   expand_fun_less      ~> fun_below_iff
   885   less_fun_ext         ~> fun_belowI
   886   less_discr_def       ~> below_discr_def
   887   discr_less_eq        ~> discr_below_eq
   888   less_unit_def        ~> below_unit_def
   889   less_cprod_def       ~> below_prod_def
   890   prod_lessI           ~> prod_belowI
   891   Pair_less_iff        ~> Pair_below_iff
   892   fst_less_iff         ~> fst_below_iff
   893   snd_less_iff         ~> snd_below_iff
   894   expand_cfun_less     ~> cfun_below_iff
   895   less_cfun_ext        ~> cfun_belowI
   896   injection_less       ~> injection_below
   897   less_up_def          ~> below_up_def
   898   not_Iup_less         ~> not_Iup_below
   899   Iup_less             ~> Iup_below
   900   up_less              ~> up_below
   901   Def_inject_less_eq   ~> Def_below_Def
   902   Def_less_is_eq       ~> Def_below_iff
   903   spair_less_iff       ~> spair_below_iff
   904   less_sprod           ~> below_sprod
   905   spair_less           ~> spair_below
   906   sfst_less_iff        ~> sfst_below_iff
   907   ssnd_less_iff        ~> ssnd_below_iff
   908   fix_least_less       ~> fix_least_below
   909   dist_less_one        ~> dist_below_one
   910   less_ONE             ~> below_ONE
   911   ONE_less_iff         ~> ONE_below_iff
   912   less_sinlD           ~> below_sinlD
   913   less_sinrD           ~> below_sinrD
   914 
   915 
   916 *** FOL and ZF ***
   917 
   918 * All constant names are now qualified internally and use proper
   919 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
   920 
   921 
   922 *** ML ***
   923 
   924 * Antiquotation @{assert} inlines a function bool -> unit that raises
   925 Fail if the argument is false.  Due to inlining the source position of
   926 failed assertions is included in the error output.
   927 
   928 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
   929 text is in practice always evaluated with a stable theory checkpoint.
   930 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
   931 
   932 * Antiquotation @{theory A} refers to theory A from the ancestry of
   933 the current context, not any accidental theory loader state as before.
   934 Potential INCOMPATIBILITY, subtle change in semantics.
   935 
   936 * Syntax.pretty_priority (default 0) configures the required priority
   937 of pretty-printed output and thus affects insertion of parentheses.
   938 
   939 * Syntax.default_root (default "any") configures the inner syntax
   940 category (nonterminal symbol) for parsing of terms.
   941 
   942 * Former exception Library.UnequalLengths now coincides with
   943 ListPair.UnequalLengths.
   944 
   945 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
   946 main functionality is provided by structure Simplifier.
   947 
   948 * Renamed raw "explode" function to "raw_explode" to emphasize its
   949 meaning.  Note that internally to Isabelle, Symbol.explode is used in
   950 almost all situations.
   951 
   952 * Discontinued obsolete function sys_error and exception SYS_ERROR.
   953 See implementation manual for further details on exceptions in
   954 Isabelle/ML.
   955 
   956 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
   957 meaning.
   958 
   959 * Renamed structure PureThy to Pure_Thy and moved most of its
   960 operations to structure Global_Theory, to emphasize that this is
   961 rarely-used global-only stuff.
   962 
   963 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
   964 instead (or tracing for high-volume output).
   965 
   966 * Configuration option show_question_marks only affects regular pretty
   967 printing of types and terms, not raw Term.string_of_vname.
   968 
   969 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
   970 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
   971 @{thms} for most purposes.
   972 
   973 * ML structure Unsynchronized is never opened, not even in Isar
   974 interaction mode as before.  Old Unsynchronized.set etc. have been
   975 discontinued -- use plain := instead.  This should be *rare* anyway,
   976 since modern tools always work via official context data, notably
   977 configuration options.
   978 
   979 * Parallel and asynchronous execution requires special care concerning
   980 interrupts.  Structure Exn provides some convenience functions that
   981 avoid working directly with raw Interrupt.  User code must not absorb
   982 interrupts -- intermediate handling (for cleanup etc.) needs to be
   983 followed by re-raising of the original exception.  Another common
   984 source of mistakes are "handle _" patterns, which make the meaning of
   985 the program subject to physical effects of the environment.
   986 
   987 
   988 
   989 New in Isabelle2009-2 (June 2010)
   990 ---------------------------------
   991 
   992 *** General ***
   993 
   994 * Authentic syntax for *all* logical entities (type classes, type
   995 constructors, term constants): provides simple and robust
   996 correspondence between formal entities and concrete syntax.  Within
   997 the parse tree / AST representations, "constants" are decorated by
   998 their category (class, type, const) and spelled out explicitly with
   999 their full internal name.
  1000 
  1001 Substantial INCOMPATIBILITY concerning low-level syntax declarations
  1002 and translations (translation rules and translation functions in ML).
  1003 Some hints on upgrading:
  1004 
  1005   - Many existing uses of 'syntax' and 'translations' can be replaced
  1006     by more modern 'type_notation', 'notation' and 'abbreviation',
  1007     which are independent of this issue.
  1008 
  1009   - 'translations' require markup within the AST; the term syntax
  1010     provides the following special forms:
  1011 
  1012       CONST c   -- produces syntax version of constant c from context
  1013       XCONST c  -- literally c, checked as constant from context
  1014       c         -- literally c, if declared by 'syntax'
  1015 
  1016     Plain identifiers are treated as AST variables -- occasionally the
  1017     system indicates accidental variables via the error "rhs contains
  1018     extra variables".
  1019 
  1020     Type classes and type constructors are marked according to their
  1021     concrete syntax.  Some old translations rules need to be written
  1022     for the "type" category, using type constructor application
  1023     instead of pseudo-term application of the default category
  1024     "logic".
  1025 
  1026   - 'parse_translation' etc. in ML may use the following
  1027     antiquotations:
  1028 
  1029       @{class_syntax c}   -- type class c within parse tree / AST
  1030       @{term_syntax c}    -- type constructor c within parse tree / AST
  1031       @{const_syntax c}   -- ML version of "CONST c" above
  1032       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
  1033 
  1034   - Literal types within 'typed_print_translations', i.e. those *not*
  1035     represented as pseudo-terms are represented verbatim.  Use @{class
  1036     c} or @{type_name c} here instead of the above syntax
  1037     antiquotations.
  1038 
  1039 Note that old non-authentic syntax was based on unqualified base
  1040 names, so all of the above "constant" names would coincide.  Recall
  1041 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
  1042 diagnose syntax problems.
  1043 
  1044 * Type constructors admit general mixfix syntax, not just infix.
  1045 
  1046 * Concrete syntax may be attached to local entities without a proof
  1047 body, too.  This works via regular mixfix annotations for 'fix',
  1048 'def', 'obtain' etc. or via the explicit 'write' command, which is
  1049 similar to the 'notation' command in theory specifications.
  1050 
  1051 * Discontinued unnamed infix syntax (legacy feature for many years) --
  1052 need to specify constant name and syntax separately.  Internal ML
  1053 datatype constructors have been renamed from InfixName to Infix etc.
  1054 Minor INCOMPATIBILITY.
  1055 
  1056 * Schematic theorem statements need to be explicitly markup as such,
  1057 via commands 'schematic_lemma', 'schematic_theorem',
  1058 'schematic_corollary'.  Thus the relevance of the proof is made
  1059 syntactically clear, which impacts performance in a parallel or
  1060 asynchronous interactive environment.  Minor INCOMPATIBILITY.
  1061 
  1062 * Use of cumulative prems via "!" in some proof methods has been
  1063 discontinued (old legacy feature).
  1064 
  1065 * References 'trace_simp' and 'debug_simp' have been replaced by
  1066 configuration options stored in the context. Enabling tracing (the
  1067 case of debugging is similar) in proofs works via
  1068 
  1069   using [[trace_simp = true]]
  1070 
  1071 Tracing is then active for all invocations of the simplifier in
  1072 subsequent goal refinement steps. Tracing may also still be enabled or
  1073 disabled via the ProofGeneral settings menu.
  1074 
  1075 * Separate commands 'hide_class', 'hide_type', 'hide_const',
  1076 'hide_fact' replace the former 'hide' KIND command.  Minor
  1077 INCOMPATIBILITY.
  1078 
  1079 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
  1080 more efficient than combinations with -q1 or -q2.
  1081 
  1082 
  1083 *** Pure ***
  1084 
  1085 * Proofterms record type-class reasoning explicitly, using the
  1086 "unconstrain" operation internally.  This eliminates all sort
  1087 constraints from a theorem and proof, introducing explicit
  1088 OFCLASS-premises.  On the proof term level, this operation is
  1089 automatically applied at theorem boundaries, such that closed proofs
  1090 are always free of sort constraints.  INCOMPATIBILITY for tools that
  1091 inspect proof terms.
  1092 
  1093 * Local theory specifications may depend on extra type variables that
  1094 are not present in the result type -- arguments TYPE('a) :: 'a itself
  1095 are added internally.  For example:
  1096 
  1097   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
  1098 
  1099 * Predicates of locales introduced by classes carry a mandatory
  1100 "class" prefix.  INCOMPATIBILITY.
  1101 
  1102 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
  1103 
  1104 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
  1105 'class' instead.
  1106 
  1107 * Command 'code_reflect' allows to incorporate generated ML code into
  1108 runtime environment; replaces immature code_datatype antiquotation.
  1109 INCOMPATIBILITY.
  1110 
  1111 * Code generator: simple concept for abstract datatypes obeying
  1112 invariants.
  1113 
  1114 * Code generator: details of internal data cache have no impact on the
  1115 user space functionality any longer.
  1116 
  1117 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  1118 subgoals.  This is more appropriate for interpretations with 'where'.
  1119 INCOMPATIBILITY.
  1120 
  1121 * Command 'example_proof' opens an empty proof body.  This allows to
  1122 experiment with Isar, without producing any persistent result.
  1123 
  1124 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  1125 within a local theory context, with explicit checking of the
  1126 constructors involved (in contrast to the raw 'syntax' versions).
  1127 
  1128 * Commands 'types' and 'typedecl' now work within a local theory
  1129 context -- without introducing dependencies on parameters or
  1130 assumptions, which is not possible in Isabelle/Pure.
  1131 
  1132 * Command 'defaultsort' has been renamed to 'default_sort', it works
  1133 within a local theory context.  Minor INCOMPATIBILITY.
  1134 
  1135 
  1136 *** HOL ***
  1137 
  1138 * Command 'typedef' now works within a local theory context -- without
  1139 introducing dependencies on parameters or assumptions, which is not
  1140 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  1141 contain multiple interpretations of local typedefs (with different
  1142 non-emptiness proofs), even in a global theory context.
  1143 
  1144 * New package for quotient types.  Commands 'quotient_type' and
  1145 'quotient_definition' may be used for defining types and constants by
  1146 quotient constructions.  An example is the type of integers created by
  1147 quotienting pairs of natural numbers:
  1148 
  1149   fun
  1150     intrel :: "(nat * nat) => (nat * nat) => bool"
  1151   where
  1152     "intrel (x, y) (u, v) = (x + v = u + y)"
  1153 
  1154   quotient_type int = "nat * nat" / intrel
  1155     by (auto simp add: equivp_def expand_fun_eq)
  1156 
  1157   quotient_definition
  1158     "0::int" is "(0::nat, 0::nat)"
  1159 
  1160 The method "lifting" can be used to lift of theorems from the
  1161 underlying "raw" type to the quotient type.  The example
  1162 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  1163 construction and provides a reasoning infrastructure for finite sets.
  1164 
  1165 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  1166 clash with new theory Quotient in Main HOL.
  1167 
  1168 * Moved the SMT binding into the main HOL session, eliminating
  1169 separate HOL-SMT session.
  1170 
  1171 * List membership infix mem operation is only an input abbreviation.
  1172 INCOMPATIBILITY.
  1173 
  1174 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  1175 for future developements; former Library/Word.thy is still present in
  1176 the AFP entry RSAPPS.
  1177 
  1178 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  1179 longer shadowed.  INCOMPATIBILITY.
  1180 
  1181 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  1182 INCOMPATIBILITY.
  1183 
  1184 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  1185 INCOMPATIBILITY.
  1186 
  1187 * Dropped normalizing_semiring etc; use the facts in semiring classes
  1188 instead.  INCOMPATIBILITY.
  1189 
  1190 * Dropped several real-specific versions of lemmas about floor and
  1191 ceiling; use the generic lemmas from theory "Archimedean_Field"
  1192 instead.  INCOMPATIBILITY.
  1193 
  1194   floor_number_of_eq         ~> floor_number_of
  1195   le_floor_eq_number_of      ~> number_of_le_floor
  1196   le_floor_eq_zero           ~> zero_le_floor
  1197   le_floor_eq_one            ~> one_le_floor
  1198   floor_less_eq_number_of    ~> floor_less_number_of
  1199   floor_less_eq_zero         ~> floor_less_zero
  1200   floor_less_eq_one          ~> floor_less_one
  1201   less_floor_eq_number_of    ~> number_of_less_floor
  1202   less_floor_eq_zero         ~> zero_less_floor
  1203   less_floor_eq_one          ~> one_less_floor
  1204   floor_le_eq_number_of      ~> floor_le_number_of
  1205   floor_le_eq_zero           ~> floor_le_zero
  1206   floor_le_eq_one            ~> floor_le_one
  1207   floor_subtract_number_of   ~> floor_diff_number_of
  1208   floor_subtract_one         ~> floor_diff_one
  1209   ceiling_number_of_eq       ~> ceiling_number_of
  1210   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  1211   ceiling_le_zero_eq         ~> ceiling_le_zero
  1212   ceiling_le_eq_one          ~> ceiling_le_one
  1213   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  1214   less_ceiling_eq_zero       ~> zero_less_ceiling
  1215   less_ceiling_eq_one        ~> one_less_ceiling
  1216   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  1217   ceiling_less_eq_zero       ~> ceiling_less_zero
  1218   ceiling_less_eq_one        ~> ceiling_less_one
  1219   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  1220   le_ceiling_eq_zero         ~> zero_le_ceiling
  1221   le_ceiling_eq_one          ~> one_le_ceiling
  1222   ceiling_subtract_number_of ~> ceiling_diff_number_of
  1223   ceiling_subtract_one       ~> ceiling_diff_one
  1224 
  1225 * Theory "Finite_Set": various folding_XXX locales facilitate the
  1226 application of the various fold combinators on finite sets.
  1227 
  1228 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  1229 provides abstract red-black tree type which is backed by "RBT_Impl" as
  1230 implementation.  INCOMPATIBILTY.
  1231 
  1232 * Theory Library/Coinductive_List has been removed -- superseded by
  1233 AFP/thys/Coinductive.
  1234 
  1235 * Theory PReal, including the type "preal" and related operations, has
  1236 been removed.  INCOMPATIBILITY.
  1237 
  1238 * Real: new development using Cauchy Sequences.
  1239 
  1240 * Split off theory "Big_Operators" containing setsum, setprod,
  1241 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  1242 
  1243 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  1244 "Int" etc.  INCOMPATIBILITY.
  1245 
  1246 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  1247 
  1248 * New set of rules "ac_simps" provides combined assoc / commute
  1249 rewrites for all interpretations of the appropriate generic locales.
  1250 
  1251 * Renamed theory "OrderedGroup" to "Groups" and split theory
  1252 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  1253 appropriate and more consistent names suitable for name prefixes
  1254 within the HOL theories.  INCOMPATIBILITY.
  1255 
  1256 * Some generic constants have been put to appropriate theories:
  1257   - less_eq, less: Orderings
  1258   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  1259   - inverse, divide: Rings
  1260 INCOMPATIBILITY.
  1261 
  1262 * More consistent naming of type classes involving orderings (and
  1263 lattices):
  1264 
  1265     lower_semilattice                   ~> semilattice_inf
  1266     upper_semilattice                   ~> semilattice_sup
  1267 
  1268     dense_linear_order                  ~> dense_linorder
  1269 
  1270     pordered_ab_group_add               ~> ordered_ab_group_add
  1271     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  1272     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  1273     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  1274     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  1275     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  1276     pordered_cancel_semiring            ~> ordered_cancel_semiring
  1277     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  1278     pordered_comm_ring                  ~> ordered_comm_ring
  1279     pordered_comm_semiring              ~> ordered_comm_semiring
  1280     pordered_ring                       ~> ordered_ring
  1281     pordered_ring_abs                   ~> ordered_ring_abs
  1282     pordered_semiring                   ~> ordered_semiring
  1283 
  1284     ordered_ab_group_add                ~> linordered_ab_group_add
  1285     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  1286     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  1287     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  1288     ordered_field                       ~> linordered_field
  1289     ordered_field_no_lb                 ~> linordered_field_no_lb
  1290     ordered_field_no_ub                 ~> linordered_field_no_ub
  1291     ordered_field_dense_linear_order    ~> dense_linordered_field
  1292     ordered_idom                        ~> linordered_idom
  1293     ordered_ring                        ~> linordered_ring
  1294     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  1295     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  1296     ordered_ring_strict                 ~> linordered_ring_strict
  1297     ordered_semidom                     ~> linordered_semidom
  1298     ordered_semiring                    ~> linordered_semiring
  1299     ordered_semiring_1                  ~> linordered_semiring_1
  1300     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  1301     ordered_semiring_strict             ~> linordered_semiring_strict
  1302 
  1303   The following slightly odd type classes have been moved to a
  1304   separate theory Library/Lattice_Algebras:
  1305 
  1306     lordered_ab_group_add               ~> lattice_ab_group_add
  1307     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  1308     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  1309     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  1310     lordered_ring                       ~> lattice_ring
  1311 
  1312 INCOMPATIBILITY.
  1313 
  1314 * Refined field classes:
  1315   - classes division_ring_inverse_zero, field_inverse_zero,
  1316     linordered_field_inverse_zero include rule inverse 0 = 0 --
  1317     subsumes former division_by_zero class;
  1318   - numerous lemmas have been ported from field to division_ring.
  1319 INCOMPATIBILITY.
  1320 
  1321 * Refined algebra theorem collections:
  1322   - dropped theorem group group_simps, use algebra_simps instead;
  1323   - dropped theorem group ring_simps, use field_simps instead;
  1324   - proper theorem collection field_simps subsumes former theorem
  1325     groups field_eq_simps and field_simps;
  1326   - dropped lemma eq_minus_self_iff which is a duplicate for
  1327     equal_neg_zero.
  1328 INCOMPATIBILITY.
  1329 
  1330 * Theory Finite_Set and List: some lemmas have been generalized from
  1331 sets to lattices:
  1332 
  1333   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  1334   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  1335   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  1336   union_Union_fold_union        ~> sup_Sup_fold_sup
  1337   Inter_fold_inter              ~> Inf_fold_inf
  1338   Union_fold_union              ~> Sup_fold_sup
  1339   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  1340   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  1341   INTER_fold_inter              ~> INFI_fold_inf
  1342   UNION_fold_union              ~> SUPR_fold_sup
  1343 
  1344 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  1345 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  1346 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  1347 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  1348 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  1349 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  1350 
  1351 * Reorganized theory Multiset: swapped notation of pointwise and
  1352 multiset order:
  1353 
  1354   - pointwise ordering is instance of class order with standard syntax
  1355     <= and <;
  1356   - multiset ordering has syntax <=# and <#; partial order properties
  1357     are provided by means of interpretation with prefix
  1358     multiset_order;
  1359   - less duplication, less historical organization of sections,
  1360     conversion from associations lists to multisets, rudimentary code
  1361     generation;
  1362   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  1363     if needed.
  1364 
  1365 Renamed:
  1366 
  1367   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  1368   multi_count_ext  ~>  multiset_ext
  1369   diff_union_inverse2  ~>  diff_union_cancelR
  1370 
  1371 INCOMPATIBILITY.
  1372 
  1373 * Theory Permutation: replaced local "remove" by List.remove1.
  1374 
  1375 * Code generation: ML and OCaml code is decorated with signatures.
  1376 
  1377 * Theory List: added transpose.
  1378 
  1379 * Library/Nat_Bijection.thy is a collection of bijective functions
  1380 between nat and other types, which supersedes the older libraries
  1381 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  1382 
  1383   Constants:
  1384   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  1385   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  1386   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  1387   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  1388   Countable.pair_encode           ~> prod_encode
  1389   NatIso.prod2nat                 ~> prod_encode
  1390   NatIso.nat2prod                 ~> prod_decode
  1391   NatIso.sum2nat                  ~> sum_encode
  1392   NatIso.nat2sum                  ~> sum_decode
  1393   NatIso.list2nat                 ~> list_encode
  1394   NatIso.nat2list                 ~> list_decode
  1395   NatIso.set2nat                  ~> set_encode
  1396   NatIso.nat2set                  ~> set_decode
  1397 
  1398   Lemmas:
  1399   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  1400   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  1401   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  1402   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  1403   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  1404   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  1405   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  1406   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  1407   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  1408   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  1409   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  1410   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  1411   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  1412 
  1413 * Sledgehammer:
  1414   - Renamed ATP commands:
  1415     atp_info     ~> sledgehammer running_atps
  1416     atp_kill     ~> sledgehammer kill_atps
  1417     atp_messages ~> sledgehammer messages
  1418     atp_minimize ~> sledgehammer minimize
  1419     print_atps   ~> sledgehammer available_atps
  1420     INCOMPATIBILITY.
  1421   - Added user's manual ("isabelle doc sledgehammer").
  1422   - Added option syntax and "sledgehammer_params" to customize
  1423     Sledgehammer's behavior.  See the manual for details.
  1424   - Modified the Isar proof reconstruction code so that it produces
  1425     direct proofs rather than proofs by contradiction.  (This feature
  1426     is still experimental.)
  1427   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  1428     full-typed mode.
  1429   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  1430 
  1431 * Nitpick:
  1432   - Added and implemented "binary_ints" and "bits" options.
  1433   - Added "std" option and implemented support for nonstandard models.
  1434   - Added and implemented "finitize" option to improve the precision
  1435     of infinite datatypes based on a monotonicity analysis.
  1436   - Added support for quotient types.
  1437   - Added support for "specification" and "ax_specification"
  1438     constructs.
  1439   - Added support for local definitions (for "function" and
  1440     "termination" proofs).
  1441   - Added support for term postprocessors.
  1442   - Optimized "Multiset.multiset" and "FinFun.finfun".
  1443   - Improved efficiency of "destroy_constrs" optimization.
  1444   - Fixed soundness bugs related to "destroy_constrs" optimization and
  1445     record getters.
  1446   - Fixed soundness bug related to higher-order constructors.
  1447   - Fixed soundness bug when "full_descrs" is enabled.
  1448   - Improved precision of set constructs.
  1449   - Added "atoms" option.
  1450   - Added cache to speed up repeated Kodkod invocations on the same
  1451     problems.
  1452   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  1453     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  1454     "SAT4J_Light".  INCOMPATIBILITY.
  1455   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  1456     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  1457   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  1458 
  1459 * Method "induct" now takes instantiations of the form t, where t is not
  1460   a variable, as a shorthand for "x == t", where x is a fresh variable.
  1461   If this is not intended, t has to be enclosed in parentheses.
  1462   By default, the equalities generated by definitional instantiations
  1463   are pre-simplified, which may cause parameters of inductive cases
  1464   to disappear, or may even delete some of the inductive cases.
  1465   Use "induct (no_simp)" instead of "induct" to restore the old
  1466   behaviour. The (no_simp) option is also understood by the "cases"
  1467   and "nominal_induct" methods, which now perform pre-simplification, too.
  1468   INCOMPATIBILITY.
  1469 
  1470 
  1471 *** HOLCF ***
  1472 
  1473 * Variable names in lemmas generated by the domain package have
  1474 changed; the naming scheme is now consistent with the HOL datatype
  1475 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  1476 
  1477 * The domain package no longer defines the function "foo_copy" for
  1478 recursive domain "foo".  The reach lemma is now stated directly in
  1479 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  1480 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  1481 
  1482 * Most definedness lemmas generated by the domain package (previously
  1483 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  1484 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  1485 Proofs that used definedness lemmas as intro rules may break,
  1486 potential INCOMPATIBILITY.
  1487 
  1488 * Induction and casedist rules generated by the domain package now
  1489 declare proper case_names (one called "bottom", and one named for each
  1490 constructor).  INCOMPATIBILITY.
  1491 
  1492 * For mutually-recursive domains, separate "reach" and "take_lemma"
  1493 rules are generated for each domain, INCOMPATIBILITY.
  1494 
  1495   foo_bar.reach       ~> foo.reach  bar.reach
  1496   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  1497 
  1498 * Some lemmas generated by the domain package have been renamed for
  1499 consistency with the datatype package, INCOMPATIBILITY.
  1500 
  1501   foo.ind        ~> foo.induct
  1502   foo.finite_ind ~> foo.finite_induct
  1503   foo.coind      ~> foo.coinduct
  1504   foo.casedist   ~> foo.exhaust
  1505   foo.exhaust    ~> foo.nchotomy
  1506 
  1507 * For consistency with other definition packages, the fixrec package
  1508 now generates qualified theorem names, INCOMPATIBILITY.
  1509 
  1510   foo_simps  ~> foo.simps
  1511   foo_unfold ~> foo.unfold
  1512   foo_induct ~> foo.induct
  1513 
  1514 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  1515 method and internal fixrec proofs now use the default simpset instead.
  1516 INCOMPATIBILITY.
  1517 
  1518 * The "contlub" predicate has been removed.  Proof scripts should use
  1519 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  1520 
  1521 * The "admw" predicate has been removed, INCOMPATIBILITY.
  1522 
  1523 * The constants cpair, cfst, and csnd have been removed in favor of
  1524 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  1525 
  1526 
  1527 *** ML ***
  1528 
  1529 * Antiquotations for basic formal entities:
  1530 
  1531     @{class NAME}         -- type class
  1532     @{class_syntax NAME}  -- syntax representation of the above
  1533 
  1534     @{type_name NAME}     -- logical type
  1535     @{type_abbrev NAME}   -- type abbreviation
  1536     @{nonterminal NAME}   -- type of concrete syntactic category
  1537     @{type_syntax NAME}   -- syntax representation of any of the above
  1538 
  1539     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  1540     @{const_abbrev NAME}  -- abbreviated constant
  1541     @{const_syntax NAME}  -- syntax representation of any of the above
  1542 
  1543 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  1544 syntax constant (cf. 'syntax' command).
  1545 
  1546 * Antiquotation @{make_string} inlines a function to print arbitrary
  1547 values similar to the ML toplevel.  The result is compiler dependent
  1548 and may fall back on "?" in certain situations.
  1549 
  1550 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  1551 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  1552 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  1553 not work with the asynchronous Isar document model.
  1554 
  1555 * Configuration options now admit dynamic default values, depending on
  1556 the context or even global references.
  1557 
  1558 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  1559 uses an efficient external library if available (for Poly/ML).
  1560 
  1561 * Renamed some important ML structures, while keeping the old names
  1562 for some time as aliases within the structure Legacy:
  1563 
  1564   OuterKeyword  ~>  Keyword
  1565   OuterLex      ~>  Token
  1566   OuterParse    ~>  Parse
  1567   OuterSyntax   ~>  Outer_Syntax
  1568   PrintMode     ~>  Print_Mode
  1569   SpecParse     ~>  Parse_Spec
  1570   ThyInfo       ~>  Thy_Info
  1571   ThyLoad       ~>  Thy_Load
  1572   ThyOutput     ~>  Thy_Output
  1573   TypeInfer     ~>  Type_Infer
  1574 
  1575 Note that "open Legacy" simplifies porting of sources, but forgetting
  1576 to remove it again will complicate porting again in the future.
  1577 
  1578 * Most operations that refer to a global context are named
  1579 accordingly, e.g. Simplifier.global_context or
  1580 ProofContext.init_global.  There are some situations where a global
  1581 context actually works, but under normal circumstances one needs to
  1582 pass the proper local context through the code!
  1583 
  1584 * Discontinued old TheoryDataFun with its copy/init operation -- data
  1585 needs to be pure.  Functor Theory_Data_PP retains the traditional
  1586 Pretty.pp argument to merge, which is absent in the standard
  1587 Theory_Data version.
  1588 
  1589 * Sorts.certify_sort and derived "cert" operations for types and terms
  1590 no longer minimize sorts.  Thus certification at the boundary of the
  1591 inference kernel becomes invariant under addition of class relations,
  1592 which is an important monotonicity principle.  Sorts are now minimized
  1593 in the syntax layer only, at the boundary between the end-user and the
  1594 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  1595 explicitly in rare situations.
  1596 
  1597 * Renamed old-style Drule.standard to Drule.export_without_context, to
  1598 emphasize that this is in no way a standard operation.
  1599 INCOMPATIBILITY.
  1600 
  1601 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  1602 usual for resolution.  Rare INCOMPATIBILITY.
  1603 
  1604 * Renamed varify/unvarify operations to varify_global/unvarify_global
  1605 to emphasize that these only work in a global situation (which is
  1606 quite rare).
  1607 
  1608 * Curried take and drop in library.ML; negative length is interpreted
  1609 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  1610 
  1611 * Proof terms: type substitutions on proof constants now use canonical
  1612 order of type variables.  INCOMPATIBILITY for tools working with proof
  1613 terms.
  1614 
  1615 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  1616 may no longer carry premises.  User-level specifications are
  1617 transformed accordingly by Thm.add_axiom/add_def.
  1618 
  1619 
  1620 *** System ***
  1621 
  1622 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  1623 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  1624 proof terms are enabled unconditionally in the new HOL-Proofs image.
  1625 
  1626 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  1627 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  1628 respectively.
  1629 
  1630 * Old lib/scripts/polyml-platform is superseded by the
  1631 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  1632 variant, even on a 64 bit machine.  The following example setting
  1633 prefers 64 bit if available:
  1634 
  1635   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  1636 
  1637 * The preliminary Isabelle/jEdit application demonstrates the emerging
  1638 Isabelle/Scala layer for advanced prover interaction and integration.
  1639 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  1640 component.
  1641 
  1642 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  1643 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  1644 similar to the default assignment of the document preparation system
  1645 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  1646 provides some operations for direct access to the font without asking
  1647 the user for manual installation.
  1648 
  1649 
  1650 
  1651 New in Isabelle2009-1 (December 2009)
  1652 -------------------------------------
  1653 
  1654 *** General ***
  1655 
  1656 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  1657 one backslash should be used, even in ML sources.
  1658 
  1659 
  1660 *** Pure ***
  1661 
  1662 * Locale interpretation propagates mixins along the locale hierarchy.
  1663 The currently only available mixins are the equations used to map
  1664 local definitions to terms of the target domain of an interpretation.
  1665 
  1666 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  1667 loc" to print all interpretations of locale "loc" in the theory.
  1668 Interpretations in proofs are not shown.
  1669 
  1670 * Thoroughly revised locales tutorial.  New section on conditional
  1671 interpretation.
  1672 
  1673 * On instantiation of classes, remaining undefined class parameters
  1674 are formally declared.  INCOMPATIBILITY.
  1675 
  1676 
  1677 *** Document preparation ***
  1678 
  1679 * New generalized style concept for printing terms: @{foo (style) ...}
  1680 instead of @{foo_style style ...}  (old form is still retained for
  1681 backward compatibility).  Styles can be also applied for
  1682 antiquotations prop, term_type and typeof.
  1683 
  1684 
  1685 *** HOL ***
  1686 
  1687 * New proof method "smt" for a combination of first-order logic with
  1688 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  1689 fixed-size bitvectors; there is also basic support for higher-order
  1690 features (esp. lambda abstractions).  It is an incomplete decision
  1691 procedure based on external SMT solvers using the oracle mechanism;
  1692 for the SMT solver Z3, this method is proof-producing.  Certificates
  1693 are provided to avoid calling the external solvers solely for
  1694 re-checking proofs.  Due to a remote SMT service there is no need for
  1695 installing SMT solvers locally.  See src/HOL/SMT.
  1696 
  1697 * New commands to load and prove verification conditions generated by
  1698 the Boogie program verifier or derived systems (e.g. the Verifying C
  1699 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1700 
  1701 * New counterexample generator tool 'nitpick' based on the Kodkod
  1702 relational model finder.  See src/HOL/Tools/Nitpick and
  1703 src/HOL/Nitpick_Examples.
  1704 
  1705 * New commands 'code_pred' and 'values' to invoke the predicate
  1706 compiler and to enumerate values of inductive predicates.
  1707 
  1708 * A tabled implementation of the reflexive transitive closure.
  1709 
  1710 * New implementation of quickcheck uses generic code generator;
  1711 default generators are provided for all suitable HOL types, records
  1712 and datatypes.  Old quickcheck can be re-activated importing theory
  1713 Library/SML_Quickcheck.
  1714 
  1715 * New testing tool Mirabelle for automated proof tools.  Applies
  1716 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1717 every proof step in a theory.  To be used in batch mode via the
  1718 "mirabelle" utility.
  1719 
  1720 * New proof method "sos" (sum of squares) for nonlinear real
  1721 arithmetic (originally due to John Harison). It requires theory
  1722 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1723 works well in practice on quantifier-free real arithmetic with +, -,
  1724 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1725 inequalities between polynomials.  It makes use of external
  1726 semidefinite programming solvers.  Method "sos" generates a
  1727 certificate that can be pasted into the proof thus avoiding the need
  1728 to call an external tool every time the proof is checked.  See
  1729 src/HOL/Library/Sum_Of_Squares.
  1730 
  1731 * New method "linarith" invokes existing linear arithmetic decision
  1732 procedure only.
  1733 
  1734 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1735 
  1736 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1737 Causes full type information to be output to the ATPs.  This slows
  1738 ATPs down considerably but eliminates a source of unsound "proofs"
  1739 that fail later.
  1740 
  1741 * New method "metisFT": A version of metis that uses full type
  1742 information in order to avoid failures of proof reconstruction.
  1743 
  1744 * New evaluator "approximate" approximates an real valued term using
  1745 the same method as the approximation method.
  1746 
  1747 * Method "approximate" now supports arithmetic expressions as
  1748 boundaries of intervals and implements interval splitting and Taylor
  1749 series expansion.
  1750 
  1751 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1752 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1753 
  1754 * New theory SupInf of the supremum and infimum operators for sets of
  1755 reals.
  1756 
  1757 * New theory Probability, which contains a development of measure
  1758 theory, eventually leading to Lebesgue integration and probability.
  1759 
  1760 * Extended Multivariate Analysis to include derivation and Brouwer's
  1761 fixpoint theorem.
  1762 
  1763 * Reorganization of number theory, INCOMPATIBILITY:
  1764   - new number theory development for nat and int, in theories Divides
  1765     and GCD as well as in new session Number_Theory
  1766   - some constants and facts now suffixed with _nat and _int
  1767     accordingly
  1768   - former session NumberTheory now named Old_Number_Theory, including
  1769     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1770   - moved theory Pocklington from src/HOL/Library to
  1771     src/HOL/Old_Number_Theory
  1772 
  1773 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1774 lcm of finite and infinite sets. It is shown that they form a complete
  1775 lattice.
  1776 
  1777 * Class semiring_div requires superclass no_zero_divisors and proof of
  1778 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1779 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1780 generalized to class semiring_div, subsuming former theorems
  1781 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1782 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1783 INCOMPATIBILITY.
  1784 
  1785 * Refinements to lattice classes and sets:
  1786   - less default intro/elim rules in locale variant, more default
  1787     intro/elim rules in class variant: more uniformity
  1788   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1789     le_inf_iff
  1790   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1791     sup_aci)
  1792   - renamed ACI to inf_sup_aci
  1793   - new class "boolean_algebra"
  1794   - class "complete_lattice" moved to separate theory
  1795     "Complete_Lattice"; corresponding constants (and abbreviations)
  1796     renamed and with authentic syntax:
  1797     Set.Inf ~>    Complete_Lattice.Inf
  1798     Set.Sup ~>    Complete_Lattice.Sup
  1799     Set.INFI ~>   Complete_Lattice.INFI
  1800     Set.SUPR ~>   Complete_Lattice.SUPR
  1801     Set.Inter ~>  Complete_Lattice.Inter
  1802     Set.Union ~>  Complete_Lattice.Union
  1803     Set.INTER ~>  Complete_Lattice.INTER
  1804     Set.UNION ~>  Complete_Lattice.UNION
  1805   - authentic syntax for
  1806     Set.Pow
  1807     Set.image
  1808   - mere abbreviations:
  1809     Set.empty               (for bot)
  1810     Set.UNIV                (for top)
  1811     Set.inter               (for inf, formerly Set.Int)
  1812     Set.union               (for sup, formerly Set.Un)
  1813     Complete_Lattice.Inter  (for Inf)
  1814     Complete_Lattice.Union  (for Sup)
  1815     Complete_Lattice.INTER  (for INFI)
  1816     Complete_Lattice.UNION  (for SUPR)
  1817   - object-logic definitions as far as appropriate
  1818 
  1819 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1820 Un_subset_iff are explicitly deleted as default simp rules; then also
  1821 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1822 deleted to achieve the desired effect.
  1823 
  1824 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1825 rules by default any longer; the same applies to min_max.inf_absorb1
  1826 etc.  INCOMPATIBILITY.
  1827 
  1828 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1829 pred_set_conv by default.  INCOMPATIBILITY.
  1830 
  1831 * Power operations on relations and functions are now one dedicated
  1832 constant "compow" with infix syntax "^^".  Power operation on
  1833 multiplicative monoids retains syntax "^" and is now defined generic
  1834 in class power.  INCOMPATIBILITY.
  1835 
  1836 * Relation composition "R O S" now has a more standard argument order:
  1837 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1838 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1839 break, since the O_assoc rule was not rewritten like this.  Fix using
  1840 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1841 
  1842 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1843 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1844 INCOMPATIBILITY.
  1845 
  1846 * Most rules produced by inductive and datatype package have mandatory
  1847 prefixes.  INCOMPATIBILITY.
  1848 
  1849 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1850 the attribute of the same name.  Each of the theorems in the list
  1851 DERIV_intros assumes composition with an additional function and
  1852 matches a variable to the derivative, which has to be solved by the
  1853 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1854 of most elementary terms.  Former Maclauren.DERIV_tac and
  1855 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1856 INCOMPATIBILITY.
  1857 
  1858 * Code generator attributes follow the usual underscore convention:
  1859     code_unfold     replaces    code unfold
  1860     code_post       replaces    code post
  1861     etc.
  1862   INCOMPATIBILITY.
  1863 
  1864 * Renamed methods:
  1865     sizechange -> size_change
  1866     induct_scheme -> induction_schema
  1867   INCOMPATIBILITY.
  1868 
  1869 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1870 INCOMPATIBILITY, use "undefined" directly.
  1871 
  1872 * Renamed theorems:
  1873     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1874     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1875     Suc_plus1 -> Suc_eq_plus1
  1876     *anti_sym -> *antisym*
  1877     vector_less_eq_def -> vector_le_def
  1878   INCOMPATIBILITY.
  1879 
  1880 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1881 INCOMPATIBILITY.
  1882 
  1883 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1884 INCOMPATIBILITY.
  1885 
  1886 
  1887 *** HOLCF ***
  1888 
  1889 * Theory Representable defines a class "rep" of domains that are
  1890 representable (via an ep-pair) in the universal domain type "udom".
  1891 Instances are provided for all type constructors defined in HOLCF.
  1892 
  1893 * The 'new_domain' command is a purely definitional version of the
  1894 domain package, for representable domains.  Syntax is identical to the
  1895 old domain package.  The 'new_domain' package also supports indirect
  1896 recursion using previously-defined type constructors.  See
  1897 src/HOLCF/ex/New_Domain.thy for examples.
  1898 
  1899 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1900 on the left-hand side of an equation, and then performs
  1901 simplification.  Rewriting is done using rules declared with the
  1902 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1903 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1904 
  1905 * The pattern-match compiler in 'fixrec' can now handle constructors
  1906 with HOL function types.  Pattern-match combinators for the Pair
  1907 constructor are pre-configured.
  1908 
  1909 * The 'fixrec' package now produces better fixed-point induction rules
  1910 for mutually-recursive definitions:  Induction rules have conclusions
  1911 of the form "P foo bar" instead of "P <foo, bar>".
  1912 
  1913 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1914 been renamed to "below".  The name "below" now replaces "less" in many
  1915 theorem names.  (Legacy theorem names using "less" are still supported
  1916 as well.)
  1917 
  1918 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1919 patterns can be used to generate strictness rules, or to make
  1920 functions more strict (much like the bang-patterns supported by the
  1921 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1922 examples.
  1923 
  1924 
  1925 *** ML ***
  1926 
  1927 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1928 errors and run-time exceptions, including detailed source positions.
  1929 
  1930 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1931 identified entries, with some additional information such as source
  1932 position, logical grouping etc.
  1933 
  1934 * Theory and context data is now introduced by the simplified and
  1935 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1936 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1937 copy operation) is still available for some time.
  1938 
  1939 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1940 provides a high-level programming interface to synchronized state
  1941 variables with atomic update.  This works via pure function
  1942 application within a critical section -- its runtime should be as
  1943 short as possible; beware of deadlocks if critical code is nested,
  1944 either directly or indirectly via other synchronized variables!
  1945 
  1946 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1947 wraps raw ML references, explicitly indicating their non-thread-safe
  1948 behaviour.  The Isar toplevel keeps this structure open, to
  1949 accommodate Proof General as well as quick and dirty interactive
  1950 experiments with references.
  1951 
  1952 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1953 parallel tactical reasoning.
  1954 
  1955 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1956 are similar to SUBPROOF, but are slightly more flexible: only the
  1957 specified parts of the subgoal are imported into the context, and the
  1958 body tactic may introduce new subgoals and schematic variables.
  1959 
  1960 * Old tactical METAHYPS, which does not observe the proof context, has
  1961 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1962 or Subgoal.FOCUS etc.
  1963 
  1964 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  1965 functors have their own ML name space there is no point to mark them
  1966 separately.)  Minor INCOMPATIBILITY.
  1967 
  1968 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  1969 
  1970 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  1971 INCOMPATIBILITY.
  1972 
  1973 * Operations of structure Skip_Proof no longer require quick_and_dirty
  1974 mode, which avoids critical setmp.
  1975 
  1976 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  1977 combinators for "args".  INCOMPATIBILITY, need to use simplified
  1978 Attrib/Method.setup introduced in Isabelle2009.
  1979 
  1980 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  1981 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  1982 last resort.  INCOMPATIBILITY.
  1983 
  1984 * Display.pretty_thm now requires a proper context (cf. former
  1985 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  1986 or even Display.pretty_thm_without_context as last resort.
  1987 INCOMPATIBILITY.
  1988 
  1989 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  1990 Syntax.pretty_typ/term directly, preferably with proper context
  1991 instead of global theory.
  1992 
  1993 
  1994 *** System ***
  1995 
  1996 * Further fine tuning of parallel proof checking, scales up to 8 cores
  1997 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  1998 usedir option -q.
  1999 
  2000 * Support for additional "Isabelle components" via etc/components, see
  2001 also the system manual.
  2002 
  2003 * The isabelle makeall tool now operates on all components with
  2004 IsaMakefile, not just hardwired "logics".
  2005 
  2006 * Removed "compress" option from isabelle-process and isabelle usedir;
  2007 this is always enabled.
  2008 
  2009 * Discontinued support for Poly/ML 4.x versions.
  2010 
  2011 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  2012 on a given logic image.  This requires the lighttpd webserver and is
  2013 currently supported on Linux only.
  2014 
  2015 
  2016 
  2017 New in Isabelle2009 (April 2009)
  2018 --------------------------------
  2019 
  2020 *** General ***
  2021 
  2022 * Simplified main Isabelle executables, with less surprises on
  2023 case-insensitive file-systems (such as Mac OS).
  2024 
  2025   - The main Isabelle tool wrapper is now called "isabelle" instead of
  2026     "isatool."
  2027 
  2028   - The former "isabelle" alias for "isabelle-process" has been
  2029     removed (should rarely occur to regular users).
  2030 
  2031   - The former "isabelle-interface" and its alias "Isabelle" have been
  2032     removed (interfaces are now regular Isabelle tools).
  2033 
  2034 Within scripts and make files, the Isabelle environment variables
  2035 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  2036 respectively.  (The latter are still available as legacy feature.)
  2037 
  2038 The old isabelle-interface wrapper could react in confusing ways if
  2039 the interface was uninstalled or changed otherwise.  Individual
  2040 interface tool configuration is now more explicit, see also the
  2041 Isabelle system manual.  In particular, Proof General is now available
  2042 via "isabelle emacs".
  2043 
  2044 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  2045 purge installed copies of Isabelle executables and re-run "isabelle
  2046 install -p ...", or use symlinks.
  2047 
  2048 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  2049 old ~/isabelle, which was slightly non-standard and apt to cause
  2050 surprises on case-insensitive file-systems (such as Mac OS).
  2051 
  2052 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  2053 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  2054 care is required when using older releases of Isabelle.  Note that
  2055 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  2056 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  2057 
  2058 * Proofs of fully specified statements are run in parallel on
  2059 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  2060 a regular 4-core machine, if the initial heap space is made reasonably
  2061 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  2062 
  2063 * The main reference manuals ("isar-ref", "implementation", and
  2064 "system") have been updated and extended.  Formally checked references
  2065 as hyperlinks are now available uniformly.
  2066 
  2067 
  2068 *** Pure ***
  2069 
  2070 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  2071 respects.  The most important changes are listed below.  See the
  2072 Tutorial on Locales ("locales" manual) for details.
  2073 
  2074 - In locale expressions, instantiation replaces renaming.  Parameters
  2075 must be declared in a for clause.  To aid compatibility with previous
  2076 parameter inheritance, in locale declarations, parameters that are not
  2077 'touched' (instantiation position "_" or omitted) are implicitly added
  2078 with their syntax at the beginning of the for clause.
  2079 
  2080 - Syntax from abbreviations and definitions in locales is available in
  2081 locale expressions and context elements.  The latter is particularly
  2082 useful in locale declarations.
  2083 
  2084 - More flexible mechanisms to qualify names generated by locale
  2085 expressions.  Qualifiers (prefixes) may be specified in locale
  2086 expressions, and can be marked as mandatory (syntax: "name!:") or
  2087 optional (syntax "name?:").  The default depends for plain "name:"
  2088 depends on the situation where a locale expression is used: in
  2089 commands 'locale' and 'sublocale' prefixes are optional, in
  2090 'interpretation' and 'interpret' prefixes are mandatory.  The old
  2091 implicit qualifiers derived from the parameter names of a locale are
  2092 no longer generated.
  2093 
  2094 - Command "sublocale l < e" replaces "interpretation l < e".  The
  2095 instantiation clause in "interpretation" and "interpret" (square
  2096 brackets) is no longer available.  Use locale expressions.
  2097 
  2098 - When converting proof scripts, mandatory qualifiers in
  2099 'interpretation' and 'interpret' should be retained by default, even
  2100 if this is an INCOMPATIBILITY compared to former behavior.  In the
  2101 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  2102 in locale expressions range over a single locale instance only.
  2103 
  2104 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  2105 In existing theorem specifications replace the includes element by the
  2106 respective context elements of the included locale, omitting those
  2107 that are already present in the theorem specification.  Multiple
  2108 assume elements of a locale should be replaced by a single one
  2109 involving the locale predicate.  In the proof body, declarations (most
  2110 notably theorems) may be regained by interpreting the respective
  2111 locales in the proof context as required (command "interpret").
  2112 
  2113 If using "includes" in replacement of a target solely because the
  2114 parameter types in the theorem are not as general as in the target,
  2115 consider declaring a new locale with additional type constraints on
  2116 the parameters (context element "constrains").
  2117 
  2118 - Discontinued "locale (open)".  INCOMPATIBILITY.
  2119 
  2120 - Locale interpretation commands no longer attempt to simplify goal.
  2121 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  2122 methods intro_locales and unfold_locales to clarify.
  2123 
  2124 - Locale interpretation commands no longer accept interpretation
  2125 attributes.  INCOMPATIBILITY.
  2126 
  2127 * Class declaration: so-called "base sort" must not be given in import
  2128 list any longer, but is inferred from the specification.  Particularly
  2129 in HOL, write
  2130 
  2131     class foo = ...
  2132 
  2133 instead of
  2134 
  2135     class foo = type + ...
  2136 
  2137 * Class target: global versions of theorems stemming do not carry a
  2138 parameter prefix any longer.  INCOMPATIBILITY.
  2139 
  2140 * Class 'instance' command no longer accepts attached definitions.
  2141 INCOMPATIBILITY, use proper 'instantiation' target instead.
  2142 
  2143 * Recovered hiding of consts, which was accidentally broken in
  2144 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  2145 makes c inaccessible; consider using ``hide (open) const c'' instead.
  2146 
  2147 * Slightly more coherent Pure syntax, with updated documentation in
  2148 isar-ref manual.  Removed locales meta_term_syntax and
  2149 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  2150 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  2151 directly in regular applications.
  2152 
  2153 * There is a new syntactic category "float_const" for signed decimal
  2154 fractions (e.g. 123.45 or -123.45).
  2155 
  2156 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  2157 interface with 'setup' command instead.
  2158 
  2159 * Command 'local_setup' is similar to 'setup', but operates on a local
  2160 theory context.
  2161 
  2162 * The 'axiomatization' command now only works within a global theory
  2163 context.  INCOMPATIBILITY.
  2164 
  2165 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  2166 hypotheses.  Sorts required in the course of reasoning need to be
  2167 covered by the constraints in the initial statement, completed by the
  2168 type instance information of the background theory.  Non-trivial sort
  2169 hypotheses, which rarely occur in practice, may be specified via
  2170 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  2171 
  2172   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  2173 
  2174 The result contains an implicit sort hypotheses as before --
  2175 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  2176 normalization.
  2177 
  2178 * Generalized Isar history, with support for linear undo, direct state
  2179 addressing etc.
  2180 
  2181 * Changed defaults for unify configuration options:
  2182 
  2183   unify_trace_bound = 50 (formerly 25)
  2184   unify_search_bound = 60 (formerly 30)
  2185 
  2186 * Different bookkeeping for code equations (INCOMPATIBILITY):
  2187 
  2188   a) On theory merge, the last set of code equations for a particular
  2189      constant is taken (in accordance with the policy applied by other
  2190      parts of the code generator framework).
  2191 
  2192   b) Code equations stemming from explicit declarations (e.g. code
  2193      attribute) gain priority over default code equations stemming
  2194      from definition, primrec, fun etc.
  2195 
  2196 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  2197 
  2198 * Unified theorem tables for both code generators.  Thus [code
  2199 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  2200 
  2201 * Command 'find_consts' searches for constants based on type and name
  2202 patterns, e.g.
  2203 
  2204     find_consts "_ => bool"
  2205 
  2206 By default, matching is against subtypes, but it may be restricted to
  2207 the whole type.  Searching by name is possible.  Multiple queries are
  2208 conjunctive and queries may be negated by prefixing them with a
  2209 hyphen:
  2210 
  2211     find_consts strict: "_ => bool" name: "Int" -"int => int"
  2212 
  2213 * New 'find_theorems' criterion "solves" matches theorems that
  2214 directly solve the current goal (modulo higher-order unification).
  2215 
  2216 * Auto solve feature for main theorem statements: whenever a new goal
  2217 is stated, "find_theorems solves" is called; any theorems that could
  2218 solve the lemma directly are listed as part of the goal state.
  2219 Cf. associated options in Proof General Isabelle settings menu,
  2220 enabled by default, with reasonable timeout for pathological cases of
  2221 higher-order unification.
  2222 
  2223 
  2224 *** Document preparation ***
  2225 
  2226 * Antiquotation @{lemma} now imitates a regular terminal proof,
  2227 demanding keyword 'by' and supporting the full method expression
  2228 syntax just like the Isar command 'by'.
  2229 
  2230 
  2231 *** HOL ***
  2232 
  2233 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  2234 points Main and Complex_Main remain as before.
  2235 
  2236 * Logic image HOL-Plain provides a minimal HOL with the most important
  2237 tools available (inductive, datatype, primrec, ...).  This facilitates
  2238 experimentation and tool development.  Note that user applications
  2239 (and library theories) should never refer to anything below theory
  2240 Main, as before.
  2241 
  2242 * Logic image HOL-Main stops at theory Main, and thus facilitates
  2243 experimentation due to shorter build times.
  2244 
  2245 * Logic image HOL-NSA contains theories of nonstandard analysis which
  2246 were previously part of former HOL-Complex.  Entry point Hyperreal
  2247 remains valid, but theories formerly using Complex_Main should now use
  2248 new entry point Hypercomplex.
  2249 
  2250 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  2251 Posix processes.  Avoids potentially expensive forking of the ML
  2252 process.  New thread-based implementation also works on non-Unix
  2253 platforms (Cygwin).  Provers are no longer hardwired, but defined
  2254 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  2255 commands are covered in the isar-ref manual.
  2256 
  2257 * Wrapper scripts for remote SystemOnTPTP service allows to use
  2258 sledgehammer without local ATP installation (Vampire etc.). Other
  2259 provers may be included via suitable ML wrappers, see also
  2260 src/HOL/ATP_Linkup.thy.
  2261 
  2262 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  2263 menu.
  2264 
  2265 * The metis method no longer fails because the theorem is too trivial
  2266 (contains the empty clause).
  2267 
  2268 * The metis method now fails in the usual manner, rather than raising
  2269 an exception, if it determines that it cannot prove the theorem.
  2270 
  2271 * Method "coherent" implements a prover for coherent logic (see also
  2272 src/Tools/coherent.ML).
  2273 
  2274 * Constants "undefined" and "default" replace "arbitrary".  Usually
  2275 "undefined" is the right choice to replace "arbitrary", though
  2276 logically there is no difference.  INCOMPATIBILITY.
  2277 
  2278 * Command "value" now integrates different evaluation mechanisms.  The
  2279 result of the first successful evaluation mechanism is printed.  In
  2280 square brackets a particular named evaluation mechanisms may be
  2281 specified (currently, [SML], [code] or [nbe]).  See further
  2282 src/HOL/ex/Eval_Examples.thy.
  2283 
  2284 * Normalization by evaluation now allows non-leftlinear equations.
  2285 Declare with attribute [code nbe].
  2286 
  2287 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  2288 as the structured Isar versions "cases" and "induct", cf. the
  2289 corresponding "cases" and "induct" attributes.  Mutual induction rules
  2290 are now presented as a list of individual projections
  2291 (e.g. foo_bar.inducts for types foo and bar); the old format with
  2292 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  2293 rare situations a different rule is selected --- notably nested tuple
  2294 elimination instead of former prod.exhaust: use explicit (case_tac t
  2295 rule: prod.exhaust) here.
  2296 
  2297 * Attributes "cases", "induct", "coinduct" support "del" option.
  2298 
  2299 * Removed fact "case_split_thm", which duplicates "case_split".
  2300 
  2301 * The option datatype has been moved to a new theory Option.  Renamed
  2302 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  2303 
  2304 * New predicate "strict_mono" classifies strict functions on partial
  2305 orders.  With strict functions on linear orders, reasoning about
  2306 (in)equalities is facilitated by theorems "strict_mono_eq",
  2307 "strict_mono_less_eq" and "strict_mono_less".
  2308 
  2309 * Some set operations are now proper qualified constants with
  2310 authentic syntax.  INCOMPATIBILITY:
  2311 
  2312     op Int ~>   Set.Int
  2313     op Un ~>    Set.Un
  2314     INTER ~>    Set.INTER
  2315     UNION ~>    Set.UNION
  2316     Inter ~>    Set.Inter
  2317     Union ~>    Set.Union
  2318     {} ~>       Set.empty
  2319     UNIV ~>     Set.UNIV
  2320 
  2321 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  2322 theory Set.
  2323 
  2324 * Auxiliary class "itself" has disappeared -- classes without any
  2325 parameter are treated as expected by the 'class' command.
  2326 
  2327 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  2328 
  2329 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  2330 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  2331 
  2332 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  2333 method "approximation".  It proves formulas on real values by using
  2334 interval arithmetic.  In the formulas are also the transcendental
  2335 functions sin, cos, tan, atan, ln, exp and the constant pi are
  2336 allowed. For examples see
  2337 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  2338 
  2339 * Theory "Reflection" now resides in HOL/Library.
  2340 
  2341 * Entry point to Word library now simply named "Word".
  2342 INCOMPATIBILITY.
  2343 
  2344 * Made source layout more coherent with logical distribution
  2345 structure:
  2346 
  2347     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  2348     src/HOL/Library/Code_Message.thy ~> src/HOL/
  2349     src/HOL/Library/GCD.thy ~> src/HOL/
  2350     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  2351     src/HOL/Library/Parity.thy ~> src/HOL/
  2352     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  2353     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  2354     src/HOL/Real/Lubs.thy ~> src/HOL/
  2355     src/HOL/Real/PReal.thy ~> src/HOL/
  2356     src/HOL/Real/Rational.thy ~> src/HOL/
  2357     src/HOL/Real/RComplete.thy ~> src/HOL/
  2358     src/HOL/Real/RealDef.thy ~> src/HOL/
  2359     src/HOL/Real/RealPow.thy ~> src/HOL/
  2360     src/HOL/Real/Real.thy ~> src/HOL/
  2361     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  2362     src/HOL/Complex/Complex.thy ~> src/HOL/
  2363     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  2364     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  2365     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  2366     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  2367     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  2368     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  2369     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  2370     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  2371     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  2372     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  2373     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  2374     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  2375     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  2376     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  2377     src/HOL/Real/Float ~> src/HOL/Library/
  2378     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  2379     src/HOL/Real/RealVector.thy ~> src/HOL/
  2380 
  2381     src/HOL/arith_data.ML ~> src/HOL/Tools
  2382     src/HOL/hologic.ML ~> src/HOL/Tools
  2383     src/HOL/simpdata.ML ~> src/HOL/Tools
  2384     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  2385     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  2386     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  2387     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  2388     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  2389     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  2390     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  2391 
  2392     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  2393     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  2394     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  2395     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  2396     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  2397     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  2398 
  2399 * If methods "eval" and "evaluation" encounter a structured proof
  2400 state with !!/==>, only the conclusion is evaluated to True (if
  2401 possible), avoiding strange error messages.
  2402 
  2403 * Method "sizechange" automates termination proofs using (a
  2404 modification of) the size-change principle.  Requires SAT solver.  See
  2405 src/HOL/ex/Termination.thy for examples.
  2406 
  2407 * Simplifier: simproc for let expressions now unfolds if bound
  2408 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  2409 
  2410 * Method "arith": Linear arithmetic now ignores all inequalities when
  2411 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  2412 
  2413 * New attribute "arith" for facts that should always be used
  2414 automatically by arithmetic. It is intended to be used locally in
  2415 proofs, e.g.
  2416 
  2417   assumes [arith]: "x > 0"
  2418 
  2419 Global usage is discouraged because of possible performance impact.
  2420 
  2421 * New classes "top" and "bot" with corresponding operations "top" and
  2422 "bot" in theory Orderings; instantiation of class "complete_lattice"
  2423 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  2424 
  2425 * Changed definition lemma "less_fun_def" in order to provide an
  2426 instance for preorders on functions; use lemma "less_le" instead.
  2427 INCOMPATIBILITY.
  2428 
  2429 * Theory Orderings: class "wellorder" moved here, with explicit
  2430 induction rule "less_induct" as assumption.  For instantiation of
  2431 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  2432 INCOMPATIBILITY.
  2433 
  2434 * Theory Orderings: added class "preorder" as superclass of "order".
  2435 INCOMPATIBILITY: Instantiation proofs for order, linorder
  2436 etc. slightly changed.  Some theorems named order_class.* now named
  2437 preorder_class.*.
  2438 
  2439 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  2440 "diag" to "Id_on".
  2441 
  2442 * Theory Finite_Set: added a new fold combinator of type
  2443 
  2444   ('a => 'b => 'b) => 'b => 'a set => 'b
  2445 
  2446 Occasionally this is more convenient than the old fold combinator
  2447 which is now defined in terms of the new one and renamed to
  2448 fold_image.
  2449 
  2450 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  2451 and "ring_simps" have been replaced by "algebra_simps" (which can be
  2452 extended with further lemmas!).  At the moment both still exist but
  2453 the former will disappear at some point.
  2454 
  2455 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  2456 class recpower.  Type-specific simp rules for various recpower types
  2457 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  2458 
  2459 rat_power_0    -> power_0
  2460 rat_power_Suc  -> power_Suc
  2461 realpow_0      -> power_0
  2462 realpow_Suc    -> power_Suc
  2463 complexpow_0   -> power_0
  2464 complexpow_Suc -> power_Suc
  2465 power_poly_0   -> power_0
  2466 power_poly_Suc -> power_Suc
  2467 
  2468 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  2469 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  2470 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  2471 of lemmas from Divides has been generalized from nat to class
  2472 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  2473 renames resulting from duplicate elimination:
  2474 
  2475     dvd_def_mod ~>          dvd_eq_mod_eq_0
  2476     zero_dvd_iff ~>         dvd_0_left_iff
  2477     dvd_0 ~>                dvd_0_right
  2478     DIVISION_BY_ZERO_DIV ~> div_by_0
  2479     DIVISION_BY_ZERO_MOD ~> mod_by_0
  2480     mult_div ~>             div_mult_self2_is_id
  2481     mult_mod ~>             mod_mult_self2_is_0
  2482 
  2483 * Theory IntDiv: removed many lemmas that are instances of class-based
  2484 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  2485 rename old lemmas as follows:
  2486 
  2487 dvd_diff               -> nat_dvd_diff
  2488 dvd_zminus_iff         -> dvd_minus_iff
  2489 mod_add1_eq            -> mod_add_eq
  2490 mod_mult1_eq           -> mod_mult_right_eq
  2491 mod_mult1_eq'          -> mod_mult_left_eq
  2492 mod_mult_distrib_mod   -> mod_mult_eq
  2493 nat_mod_add_left_eq    -> mod_add_left_eq
  2494 nat_mod_add_right_eq   -> mod_add_right_eq
  2495 nat_mod_div_trivial    -> mod_div_trivial
  2496 nat_mod_mod_trivial    -> mod_mod_trivial
  2497 zdiv_zadd_self1        -> div_add_self1
  2498 zdiv_zadd_self2        -> div_add_self2
  2499 zdiv_zmult_self1       -> div_mult_self2_is_id
  2500 zdiv_zmult_self2       -> div_mult_self1_is_id
  2501 zdvd_triv_left         -> dvd_triv_left
  2502 zdvd_triv_right        -> dvd_triv_right
  2503 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  2504 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  2505 zmod_zadd_left_eq      -> mod_add_left_eq
  2506 zmod_zadd_right_eq     -> mod_add_right_eq
  2507 zmod_zadd_self1        -> mod_add_self1
  2508 zmod_zadd_self2        -> mod_add_self2
  2509 zmod_zadd1_eq          -> mod_add_eq
  2510 zmod_zdiff1_eq         -> mod_diff_eq
  2511 zmod_zdvd_zmod         -> mod_mod_cancel
  2512 zmod_zmod_cancel       -> mod_mod_cancel
  2513 zmod_zmult_self1       -> mod_mult_self2_is_0
  2514 zmod_zmult_self2       -> mod_mult_self1_is_0
  2515 zmod_1                 -> mod_by_1
  2516 zdiv_1                 -> div_by_1
  2517 zdvd_abs1              -> abs_dvd_iff
  2518 zdvd_abs2              -> dvd_abs_iff
  2519 zdvd_refl              -> dvd_refl
  2520 zdvd_trans             -> dvd_trans
  2521 zdvd_zadd              -> dvd_add
  2522 zdvd_zdiff             -> dvd_diff
  2523 zdvd_zminus_iff        -> dvd_minus_iff
  2524 zdvd_zminus2_iff       -> minus_dvd_iff
  2525 zdvd_zmultD            -> dvd_mult_right
  2526 zdvd_zmultD2           -> dvd_mult_left
  2527 zdvd_zmult_mono        -> mult_dvd_mono
  2528 zdvd_0_right           -> dvd_0_right
  2529 zdvd_0_left            -> dvd_0_left_iff
  2530 zdvd_1_left            -> one_dvd
  2531 zminus_dvd_iff         -> minus_dvd_iff
  2532 
  2533 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  2534 
  2535 * The real numbers offer decimal input syntax: 12.34 is translated
  2536 into 1234/10^2. This translation is not reversed upon output.
  2537 
  2538 * Theory Library/Polynomial defines an abstract type 'a poly of
  2539 univariate polynomials with coefficients of type 'a.  In addition to
  2540 the standard ring operations, it also supports div and mod.  Code
  2541 generation is also supported, using list-style constructors.
  2542 
  2543 * Theory Library/Inner_Product defines a class of real_inner for real
  2544 inner product spaces, with an overloaded operation inner :: 'a => 'a
  2545 => real.  Class real_inner is a subclass of real_normed_vector from
  2546 theory RealVector.
  2547 
  2548 * Theory Library/Product_Vector provides instances for the product
  2549 type 'a * 'b of several classes from RealVector and Inner_Product.
  2550 Definitions of addition, subtraction, scalar multiplication, norms,
  2551 and inner products are included.
  2552 
  2553 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  2554 addition to the field operations, numerals and case syntax are also
  2555 supported.
  2556 
  2557 * Theory Library/Diagonalize provides constructive version of Cantor's
  2558 first diagonalization argument.
  2559 
  2560 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  2561 zlcm (for int); carried together from various gcd/lcm developements in
  2562 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  2563 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  2564 may recover tupled syntax as follows:
  2565 
  2566     hide (open) const gcd
  2567     abbreviation gcd where
  2568       "gcd == (%(a, b). GCD.gcd a b)"
  2569     notation (output)
  2570       GCD.gcd ("gcd '(_, _')")
  2571 
  2572 The same works for lcm, zgcd, zlcm.
  2573 
  2574 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  2575 instantiations for algebraic structures.  Removed some duplicate
  2576 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  2577 
  2578 * ML antiquotation @{code} takes a constant as argument and generates
  2579 corresponding code in background and inserts name of the corresponding
  2580 resulting ML value/function/datatype constructor binding in place.
  2581 All occurrences of @{code} with a single ML block are generated
  2582 simultaneously.  Provides a generic and safe interface for
  2583 instrumentalizing code generation.  See
  2584 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  2585 In future you ought to refrain from ad-hoc compiling generated SML
  2586 code on the ML toplevel.  Note that (for technical reasons) @{code}
  2587 cannot refer to constants for which user-defined serializations are
  2588 set.  Refer to the corresponding ML counterpart directly in that
  2589 cases.
  2590 
  2591 * Command 'rep_datatype': instead of theorem names the command now
  2592 takes a list of terms denoting the constructors of the type to be
  2593 represented as datatype.  The characteristic theorems have to be
  2594 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  2595 have disappeared in favour of existing ones:
  2596 
  2597     unit_induct                 ~> unit.induct
  2598     prod_induct                 ~> prod.induct
  2599     sum_induct                  ~> sum.induct
  2600     Suc_Suc_eq                  ~> nat.inject
  2601     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  2602 
  2603 
  2604 *** HOL-Algebra ***
  2605 
  2606 * New locales for orders and lattices where the equivalence relation
  2607 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  2608 locales use a record structure with field eq for the equivalence.
  2609 
  2610 * New theory of factorial domains.
  2611 
  2612 * Units_l_inv and Units_r_inv are now simp rules by default.
  2613 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  2614 and/or r_inv will now also require deletion of these lemmas.
  2615 
  2616 * Renamed the following theorems, INCOMPATIBILITY:
  2617 
  2618 UpperD ~> Upper_memD
  2619 LowerD ~> Lower_memD
  2620 least_carrier ~> least_closed
  2621 greatest_carrier ~> greatest_closed
  2622 greatest_Lower_above ~> greatest_Lower_below
  2623 one_zero ~> carrier_one_zero
  2624 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  2625 
  2626 
  2627 *** HOL-Nominal ***
  2628 
  2629 * Nominal datatypes can now contain type-variables.
  2630 
  2631 * Commands 'nominal_inductive' and 'equivariance' work with local
  2632 theory targets.
  2633 
  2634 * Nominal primrec can now works with local theory targets and its
  2635 specification syntax now conforms to the general format as seen in
  2636 'inductive' etc.
  2637 
  2638 * Method "perm_simp" honours the standard simplifier attributes
  2639 (no_asm), (no_asm_use) etc.
  2640 
  2641 * The new predicate #* is defined like freshness, except that on the
  2642 left hand side can be a set or list of atoms.
  2643 
  2644 * Experimental command 'nominal_inductive2' derives strong induction
  2645 principles for inductive definitions.  In contrast to
  2646 'nominal_inductive', which can only deal with a fixed number of
  2647 binders, it can deal with arbitrary expressions standing for sets of
  2648 atoms to be avoided.  The only inductive definition we have at the
  2649 moment that needs this generalisation is the typing rule for Lets in
  2650 the algorithm W:
  2651 
  2652  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  2653  -----------------------------------------------------------------
  2654          Gamma |- Let x be t1 in t2 : T2
  2655 
  2656 In this rule one wants to avoid all the binders that are introduced by
  2657 "close Gamma T1".  We are looking for other examples where this
  2658 feature might be useful.  Please let us know.
  2659 
  2660 
  2661 *** HOLCF ***
  2662 
  2663 * Reimplemented the simplification procedure for proving continuity
  2664 subgoals.  The new simproc is extensible; users can declare additional
  2665 continuity introduction rules with the attribute [cont2cont].
  2666 
  2667 * The continuity simproc now uses a different introduction rule for
  2668 solving continuity subgoals on terms with lambda abstractions.  In
  2669 some rare cases the new simproc may fail to solve subgoals that the
  2670 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  2671 Potential INCOMPATIBILITY.
  2672 
  2673 * Command 'fixrec': specification syntax now conforms to the general
  2674 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  2675 examples.  INCOMPATIBILITY.
  2676 
  2677 
  2678 *** ZF ***
  2679 
  2680 * Proof of Zorn's Lemma for partial orders.
  2681 
  2682 
  2683 *** ML ***
  2684 
  2685 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  2686 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  2687 depends on multithreading, so timouts will not work before Poly/ML
  2688 5.2.1!
  2689 
  2690 * High-level support for concurrent ML programming, see
  2691 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  2692 particularly convenient to organize independent functional
  2693 computations.  The concept of "synchronized variables" provides a
  2694 higher-order interface for components with shared state, avoiding the
  2695 delicate details of mutexes and condition variables.  (Requires
  2696 Poly/ML 5.2.1 or later.)
  2697 
  2698 * ML bindings produced via Isar commands are stored within the Isar
  2699 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2700 become thread-safe and work with undo as expected (concerning
  2701 top-level bindings, not side-effects on global references).
  2702 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2703 compiler at runtime; really global bindings need to be given outside a
  2704 theory.  (Requires Poly/ML 5.2 or later.)
  2705 
  2706 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2707 context.  Top-level ML bindings are stored within the proof context in
  2708 a purely sequential fashion, disregarding the nested proof structure.
  2709 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2710 proof.  (Requires Poly/ML 5.2 or later.)
  2711 
  2712 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2713 and Method.setup, as well as Isar commands 'attribute_setup' and
  2714 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2715 existing code accordingly, or use plain 'setup' together with old
  2716 Method.add_method.
  2717 
  2718 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2719 to 'a -> thm, while results are always tagged with an authentic oracle
  2720 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2721 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2722 accordingly.  Note that extra performance may be gained by producing
  2723 the cterm carefully, avoiding slow Thm.cterm_of.
  2724 
  2725 * Simplified interface for defining document antiquotations via
  2726 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2727 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2728 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2729 examples.
  2730 
  2731 * More systematic treatment of long names, abstract name bindings, and
  2732 name space operations.  Basic operations on qualified names have been
  2733 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2734 Long_Name.append.  Old type bstring has been mostly replaced by
  2735 abstract type binding (see structure Binding), which supports precise
  2736 qualification by packages and local theory targets, as well as proper
  2737 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2738 bstring values into Binding.name, or better pass through abstract
  2739 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2740 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2741 
  2742 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2743 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2744 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2745 
  2746 * Disposed old type and term read functions (Sign.read_def_typ,
  2747 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2748 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2749 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2750 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2751 resort for legacy applications.
  2752 
  2753 * Disposed old declarations, tactics, tactic combinators that refer to
  2754 the simpset or claset of an implicit theory (such as Addsimps,
  2755 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2756 embedded ML text, or local_simpset_of with a proper context passed as
  2757 explicit runtime argument.
  2758 
  2759 * Rules and tactics that read instantiations (read_instantiate,
  2760 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2761 context, which is required for parsing and type-checking.  Moreover,
  2762 the variables are specified as plain indexnames, not string encodings
  2763 thereof.  INCOMPATIBILITY.
  2764 
  2765 * Generic Toplevel.add_hook interface allows to analyze the result of
  2766 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2767 for theorem dependency output of transactions resulting in a new
  2768 theory state.
  2769 
  2770 * ML antiquotations: block-structured compilation context indicated by
  2771 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2772 
  2773   @{binding name}                         - basic name binding
  2774   @{let ?pat = term}                      - term abbreviation (HO matching)
  2775   @{note name = fact}                     - fact abbreviation
  2776   @{thm fact}                             - singleton fact (with attributes)
  2777   @{thms fact}                            - general fact (with attributes)
  2778   @{lemma prop by method}                 - singleton goal
  2779   @{lemma prop by meth1 meth2}            - singleton goal
  2780   @{lemma prop1 ... propN by method}      - general goal
  2781   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2782   @{lemma (open) ...}                     - open derivation
  2783 
  2784 
  2785 *** System ***
  2786 
  2787 * The Isabelle "emacs" tool provides a specific interface to invoke
  2788 Proof General / Emacs, with more explicit failure if that is not
  2789 installed (the old isabelle-interface script silently falls back on
  2790 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2791 installation location of the Proof General distribution.
  2792 
  2793 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2794 the Isabelle process into a JVM/Scala application.  See
  2795 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2796 process wrapper has been discontinued.)
  2797 
  2798 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2799 
  2800 * Various status messages (with exact source position information) are
  2801 emitted, if proper markup print mode is enabled.  This allows
  2802 user-interface components to provide detailed feedback on internal
  2803 prover operations.
  2804 
  2805 
  2806 
  2807 New in Isabelle2008 (June 2008)
  2808 -------------------------------
  2809 
  2810 *** General ***
  2811 
  2812 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2813 and updated, with formally checked references as hyperlinks.
  2814 
  2815 * Theory loader: use_thy (and similar operations) no longer set the
  2816 implicit ML context, which was occasionally hard to predict and in
  2817 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2818 provides a proper context already.
  2819 
  2820 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2821 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2822 'use' within a theory file will do the job.
  2823 
  2824 * Name space merge now observes canonical order, i.e. the second space
  2825 is inserted into the first one, while existing entries in the first
  2826 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2827 swap theory imports.
  2828 
  2829 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2830 INCOMPATIBILITY in identifier syntax etc.
  2831 
  2832 * Outer syntax: string tokens no longer admit escaped white space,
  2833 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2834 white space without escapes.
  2835 
  2836 * Outer syntax: string tokens may contain arbitrary character codes
  2837 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2838 "foo_bar".
  2839 
  2840 
  2841 *** Pure ***
  2842 
  2843 * Context-dependent token translations.  Default setup reverts locally
  2844 fixed variables, and adds hilite markup for undeclared frees.
  2845 
  2846 * Unused theorems can be found using the new command 'unused_thms'.
  2847 There are three ways of invoking it:
  2848 
  2849 (1) unused_thms
  2850      Only finds unused theorems in the current theory.
  2851 
  2852 (2) unused_thms thy_1 ... thy_n -
  2853      Finds unused theorems in the current theory and all of its ancestors,
  2854      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2855 
  2856 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2857      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2858      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2859      their ancestors.
  2860 
  2861 In order to increase the readability of the list produced by
  2862 unused_thms, theorems that have been created by a particular instance
  2863 of a theory command such as 'inductive' or 'function' are considered
  2864 to belong to the same "group", meaning that if at least one theorem in
  2865 this group is used, the other theorems in the same group are no longer
  2866 reported as unused.  Moreover, if all theorems in the group are
  2867 unused, only one theorem in the group is displayed.
  2868 
  2869 Note that proof objects have to be switched on in order for
  2870 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2871 usually the case when using Proof General with the default settings).
  2872 
  2873 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2874 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2875 duplicate fact bindings, or even accidental fact duplications.  Note
  2876 that tools may maintain dynamically scoped facts systematically, using
  2877 PureThy.add_thms_dynamic.
  2878 
  2879 * Command 'hide' now allows to hide from "fact" name space as well.
  2880 
  2881 * Eliminated destructive theorem database, simpset, claset, and
  2882 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2883 update of theories within ML code.
  2884 
  2885 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2886 INCOMPATIBILITY, object-logics depending on former Pure require
  2887 additional setup PureThy.old_appl_syntax_setup; object-logics
  2888 depending on former CPure need to refer to Pure.
  2889 
  2890 * Commands 'use' and 'ML' are now purely functional, operating on
  2891 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2892 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2893 INCOMPATIBILITY.
  2894 
  2895 * Command 'setup': discontinued implicit version with ML reference.
  2896 
  2897 * Instantiation target allows for simultaneous specification of class
  2898 instance operations together with an instantiation proof.
  2899 Type-checking phase allows to refer to class operations uniformly.
  2900 See src/HOL/Complex/Complex.thy for an Isar example and
  2901 src/HOL/Library/Eval.thy for an ML example.
  2902 
  2903 * Indexing of literal facts: be more serious about including only
  2904 facts from the visible specification/proof context, but not the
  2905 background context (locale etc.).  Affects `prop` notation and method
  2906 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2907 situations.
  2908 
  2909 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2910 "(open)" option, which used to expose internal bound variables to the
  2911 proof text.
  2912 
  2913 * Isar statements: removed obsolete case "rule_context".
  2914 INCOMPATIBILITY, better use explicit fixes/assumes.
  2915 
  2916 * Locale proofs: default proof step now includes 'unfold_locales';
  2917 hence 'proof' without argument may be used to unfold locale
  2918 predicates.
  2919 
  2920 
  2921 *** Document preparation ***
  2922 
  2923 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2924 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2925 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2926 spot); renamed link color from "darkblue" to "linkcolor" (default
  2927 value unchanged, can be redefined via \definecolor); no longer sets
  2928 "a4paper" option (unnecessary or even intrusive).
  2929 
  2930 * Antiquotation @{lemma A method} proves proposition A by the given
  2931 method (either a method name or a method name plus (optional) method
  2932 arguments in parentheses) and prints A just like @{prop A}.
  2933 
  2934 
  2935 *** HOL ***
  2936 
  2937 * New primrec package.  Specification syntax conforms in style to
  2938 definition/function/....  No separate induction rule is provided.  The
  2939 "primrec" command distinguishes old-style and new-style specifications
  2940 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2941 When adjusting theories, beware: constants stemming from new-style
  2942 primrec specifications have authentic syntax.
  2943 
  2944 * Metis prover is now an order of magnitude faster, and also works
  2945 with multithreading.
  2946 
  2947 * Metis: the maximum number of clauses that can be produced from a
  2948 theorem is now given by the attribute max_clauses.  Theorems that
  2949 exceed this number are ignored, with a warning printed.
  2950 
  2951 * Sledgehammer no longer produces structured proofs by default. To
  2952 enable, declare [[sledgehammer_full = true]].  Attributes
  2953 reconstruction_modulus, reconstruction_sorts renamed
  2954 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2955 
  2956 * Method "induct_scheme" derives user-specified induction rules
  2957 from well-founded induction and completeness of patterns. This factors
  2958 out some operations that are done internally by the function package
  2959 and makes them available separately.  See
  2960 src/HOL/ex/Induction_Scheme.thy for examples.
  2961 
  2962 * More flexible generation of measure functions for termination
  2963 proofs: Measure functions can be declared by proving a rule of the
  2964 form "is_measure f" and giving it the [measure_function] attribute.
  2965 The "is_measure" predicate is logically meaningless (always true), and
  2966 just guides the heuristic.  To find suitable measure functions, the
  2967 termination prover sets up the goal "is_measure ?f" of the appropriate
  2968 type and generates all solutions by prolog-style backwards proof using
  2969 the declared rules.
  2970 
  2971 This setup also deals with rules like 
  2972 
  2973   "is_measure f ==> is_measure (list_size f)"
  2974 
  2975 which accommodates nested datatypes that recurse through lists.
  2976 Similar rules are predeclared for products and option types.
  2977 
  2978 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  2979 
  2980   INCOMPATIBILITIES:
  2981 
  2982   - Definitions of overloaded constants on sets have to be replaced by
  2983     definitions on => and bool.
  2984 
  2985   - Some definitions of overloaded operators on sets can now be proved
  2986     using the definitions of the operators on => and bool.  Therefore,
  2987     the following theorems have been renamed:
  2988 
  2989       subset_def   -> subset_eq
  2990       psubset_def  -> psubset_eq
  2991       set_diff_def -> set_diff_eq
  2992       Compl_def    -> Compl_eq
  2993       Sup_set_def  -> Sup_set_eq
  2994       Inf_set_def  -> Inf_set_eq
  2995       sup_set_def  -> sup_set_eq
  2996       inf_set_def  -> inf_set_eq
  2997 
  2998   - Due to the incompleteness of the HO unification algorithm, some
  2999     rules such as subst may require manual instantiation, if some of
  3000     the unknowns in the rule is a set.
  3001 
  3002   - Higher order unification and forward proofs:
  3003     The proof pattern
  3004 
  3005       have "P (S::'a set)" <...>
  3006       then have "EX S. P S" ..
  3007 
  3008     no longer works (due to the incompleteness of the HO unification
  3009     algorithm) and must be replaced by the pattern
  3010 
  3011       have "EX S. P S"
  3012       proof
  3013         show "P S" <...>
  3014       qed
  3015 
  3016   - Calculational reasoning with subst (or similar rules):
  3017     The proof pattern
  3018 
  3019       have "P (S::'a set)" <...>
  3020       also have "S = T" <...>
  3021       finally have "P T" .
  3022 
  3023     no longer works (for similar reasons as the previous example) and
  3024     must be replaced by something like
  3025 
  3026       have "P (S::'a set)" <...>
  3027       moreover have "S = T" <...>
  3028       ultimately have "P T" by simp
  3029 
  3030   - Tactics or packages written in ML code:
  3031     Code performing pattern matching on types via
  3032 
  3033       Type ("set", [T]) => ...
  3034 
  3035     must be rewritten. Moreover, functions like strip_type or
  3036     binder_types no longer return the right value when applied to a
  3037     type of the form
  3038 
  3039       T1 => ... => Tn => U => bool
  3040 
  3041     rather than
  3042 
  3043       T1 => ... => Tn => U set
  3044 
  3045 * Merged theories Wellfounded_Recursion, Accessible_Part and
  3046 Wellfounded_Relations to theory Wellfounded.
  3047 
  3048 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  3049 
  3050 * Class finite no longer treats UNIV as class parameter.  Use class
  3051 enum from theory Library/Enum instead to achieve a similar effect.
  3052 INCOMPATIBILITY.
  3053 
  3054 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  3055 and "Cons".  INCOMPATIBILITY.
  3056 
  3057 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  3058 Potential INCOMPATIBILITY.
  3059 
  3060 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  3061 injective_fst_snd removed, use split_eta and prod_eqI instead.
  3062 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  3063 
  3064 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  3065 the same name in theory Orderings:
  3066 
  3067   less_trans
  3068   less_linear
  3069   le_imp_less_or_eq
  3070   le_less_trans
  3071   less_le_trans
  3072   less_not_sym
  3073   less_asym
  3074 
  3075 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  3076 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  3077 and different variable names.
  3078 
  3079 * Library/Option_ord.thy: Canonical order on option type.
  3080 
  3081 * Library/RBT.thy: Red-black trees, an efficient implementation of
  3082 finite maps.
  3083 
  3084 * Library/Countable.thy: Type class for countable types.
  3085 
  3086 * Theory Int: The representation of numerals has changed.  The infix
  3087 operator BIT and the bit datatype with constructors B0 and B1 have
  3088 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  3089 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  3090 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  3091 accordingly.
  3092 
  3093 * Theory Nat: definition of <= and < on natural numbers no longer
  3094 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  3095 le_def and less_def have disappeared.  Consider lemmas not_less
  3096 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  3097 
  3098 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  3099 (whose purpose mainly is for various fold_set functionals) have been
  3100 abandoned in favor of the existing algebraic classes
  3101 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  3102 lower_semilattice (resp. upper_semilattice) and linorder.
  3103 INCOMPATIBILITY.
  3104 
  3105 * Theory Transitive_Closure: induct and cases rules now declare proper
  3106 case_names ("base" and "step").  INCOMPATIBILITY.
  3107 
  3108 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  3109 lattices.  The form set-specific version is available as
  3110 Inductive.lfp_ordinal_induct_set.
  3111 
  3112 * Renamed theorems "power.simps" to "power_int.simps".
  3113 INCOMPATIBILITY.
  3114 
  3115 * Class semiring_div provides basic abstract properties of semirings
  3116 with division and modulo operations.  Subsumes former class dvd_mod.
  3117 
  3118 * Merged theories IntDef, Numeral and IntArith into unified theory
  3119 Int.  INCOMPATIBILITY.
  3120 
  3121 * Theory Library/Code_Index: type "index" now represents natural
  3122 numbers rather than integers.  INCOMPATIBILITY.
  3123 
  3124 * New class "uminus" with operation "uminus" (split of from class
  3125 "minus" which now only has operation "minus", binary).
  3126 INCOMPATIBILITY.
  3127 
  3128 * Constants "card", "internal_split", "option_map" now with authentic
  3129 syntax.  INCOMPATIBILITY.
  3130 
  3131 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  3132 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  3133 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  3134 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  3135 Sup_set_def, le_def, less_def, option_map_def now with object
  3136 equality.  INCOMPATIBILITY.
  3137 
  3138 * Records. Removed K_record, and replaced it by pure lambda term
  3139 %x. c. The simplifier setup is now more robust against eta expansion.
  3140 INCOMPATIBILITY: in cases explicitly referring to K_record.
  3141 
  3142 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  3143 
  3144 * Library/ListVector: new theory of arithmetic vector operations.
  3145 
  3146 * Library/Order_Relation: new theory of various orderings as sets of
  3147 pairs.  Defines preorders, partial orders, linear orders and
  3148 well-orders on sets and on types.
  3149 
  3150 
  3151 *** ZF ***
  3152 
  3153 * Renamed some theories to allow to loading both ZF and HOL in the
  3154 same session:
  3155 
  3156   Datatype  -> Datatype_ZF
  3157   Inductive -> Inductive_ZF
  3158   Int       -> Int_ZF
  3159   IntDiv    -> IntDiv_ZF
  3160   Nat       -> Nat_ZF
  3161   List      -> List_ZF
  3162   Main      -> Main_ZF
  3163 
  3164 INCOMPATIBILITY: ZF theories that import individual theories below
  3165 Main might need to be adapted.  Regular theory Main is still
  3166 available, as trivial extension of Main_ZF.
  3167 
  3168 
  3169 *** ML ***
  3170 
  3171 * ML within Isar: antiquotation @{const name} or @{const
  3172 name(typargs)} produces statically-checked Const term.
  3173 
  3174 * Functor NamedThmsFun: data is available to the user as dynamic fact
  3175 (of the same name).  Removed obsolete print command.
  3176 
  3177 * Removed obsolete "use_legacy_bindings" function.
  3178 
  3179 * The ``print mode'' is now a thread-local value derived from a global
  3180 template (the former print_mode reference), thus access becomes
  3181 non-critical.  The global print_mode reference is for session
  3182 management only; user-code should use print_mode_value,
  3183 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  3184 
  3185 * Functions system/system_out provide a robust way to invoke external
  3186 shell commands, with propagation of interrupts (requires Poly/ML
  3187 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  3188 
  3189 
  3190 *** System ***
  3191 
  3192 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  3193 in accordance with Proof General 3.7, which prefers GNU emacs.
  3194 
  3195 * isatool tty runs Isabelle process with plain tty interaction;
  3196 optional line editor may be specified via ISABELLE_LINE_EDITOR
  3197 setting, the default settings attempt to locate "ledit" and "rlwrap".
  3198 
  3199 * isatool browser now works with Cygwin as well, using general
  3200 "javapath" function defined in Isabelle process environment.
  3201 
  3202 * YXML notation provides a simple and efficient alternative to
  3203 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  3204 isatool yxml as described in the Isabelle system manual.
  3205 
  3206 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  3207 provides general wrapper for managing an Isabelle process in a robust
  3208 fashion, with ``cooked'' output from stdin/stderr.
  3209 
  3210 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  3211 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  3212 
  3213 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  3214 way of changing the user's settings is via
  3215 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  3216 script.
  3217 
  3218 * Multithreading.max_threads := 0 refers to the number of actual CPU
  3219 cores of the underlying machine, which is a good starting point for
  3220 optimal performance tuning.  The corresponding usedir option -M allows
  3221 "max" as an alias for "0".  WARNING: does not work on certain versions
  3222 of Mac OS (with Poly/ML 5.1).
  3223 
  3224 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  3225 adverse effect of Isabelle flooding interactive front-ends (notably
  3226 ProofGeneral / XEmacs).
  3227 
  3228 
  3229 
  3230 New in Isabelle2007 (November 2007)
  3231 -----------------------------------
  3232 
  3233 *** General ***
  3234 
  3235 * More uniform information about legacy features, notably a
  3236 warning/error of "Legacy feature: ...", depending on the state of the
  3237 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  3238 legacy features will disappear eventually.
  3239 
  3240 * Theory syntax: the header format ``theory A = B + C:'' has been
  3241 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  3242 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  3243 
  3244 * Theory syntax: the old non-Isar theory file format has been
  3245 discontinued altogether.  Note that ML proof scripts may still be used
  3246 with Isar theories; migration is usually quite simple with the ML
  3247 function use_legacy_bindings.  INCOMPATIBILITY.
  3248 
  3249 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  3250 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  3251 quotes.
  3252 
  3253 * Theory loader: be more serious about observing the static theory
  3254 header specifications (including optional directories), but not the
  3255 accidental file locations of previously successful loads.  The strict
  3256 update policy of former update_thy is now already performed by
  3257 use_thy, so the former has been removed; use_thys updates several
  3258 theories simultaneously, just as 'imports' within a theory header
  3259 specification, but without merging the results.  Potential
  3260 INCOMPATIBILITY: may need to refine theory headers and commands
  3261 ROOT.ML which depend on load order.
  3262 
  3263 * Theory loader: optional support for content-based file
  3264 identification, instead of the traditional scheme of full physical
  3265 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  3266 (cf. the system manual).  The new scheme allows to work with
  3267 non-finished theories in persistent session images, such that source
  3268 files may be moved later on without requiring reloads.
  3269 
  3270 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3271 file (with the same base name as the theory) are considered a legacy
  3272 feature, which will disappear eventually. Even now, the theory loader
  3273 no longer maintains dependencies on such files.
  3274 
  3275 * Syntax: the scope for resolving ambiguities via type-inference is
  3276 now limited to individual terms, instead of whole simultaneous
  3277 specifications as before. This greatly reduces the complexity of the
  3278 syntax module and improves flexibility by separating parsing and
  3279 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  3280 'fixes' etc.) are required in rare situations.
  3281 
  3282 * Syntax: constants introduced by new-style packages ('definition',
  3283 'abbreviation' etc.) are passed through the syntax module in
  3284 ``authentic mode''. This means that associated mixfix annotations
  3285 really stick to such constants, independently of potential name space
  3286 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  3287 trees are represented slightly differently, may need to adapt syntax
  3288 translations accordingly. Use CONST marker in 'translations' and
  3289 @{const_syntax} antiquotation in 'parse_translation' etc.
  3290 
  3291 * Legacy goal package: reduced interface to the bare minimum required
  3292 to keep existing proof scripts running.  Most other user-level
  3293 functions are now part of the OldGoals structure, which is *not* open
  3294 by default (consider isatool expandshort before open OldGoals).
  3295 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  3296 these tend to cause confusion about the actual goal (!) context being
  3297 used here, which is not necessarily the same as the_context().
  3298 
  3299 * Command 'find_theorems': supports "*" wild-card in "name:"
  3300 criterion; "with_dups" option.  Certain ProofGeneral versions might
  3301 support a specific search form (see ProofGeneral/CHANGES).
  3302 
  3303 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  3304 by default, which means that "prems" (and also "fixed variables") are
  3305 suppressed from proof state output.  Note that the ProofGeneral
  3306 settings mechanism allows to change and save options persistently, but
  3307 older versions of Isabelle will fail to start up if a negative prems
  3308 limit is imposed.
  3309 
  3310 * Local theory targets may be specified by non-nested blocks of
  3311 ``context/locale/class ... begin'' followed by ``end''.  The body may
  3312 contain definitions, theorems etc., including any derived mechanism
  3313 that has been implemented on top of these primitives.  This concept
  3314 generalizes the existing ``theorem (in ...)'' towards more versatility
  3315 and scalability.
  3316 
  3317 * Proof General interface: proper undo of final 'end' command;
  3318 discontinued Isabelle/classic mode (ML proof scripts).
  3319 
  3320 
  3321 *** Document preparation ***
  3322 
  3323 * Added antiquotation @{theory name} which prints the given name,
  3324 after checking that it refers to a valid ancestor theory in the
  3325 current context.
  3326 
  3327 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  3328 check the given source text as ML type/structure, printing verbatim.
  3329 
  3330 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  3331 "c args == rhs" given in the current context.  (Any number of
  3332 arguments may be given on the LHS.)
  3333 
  3334 
  3335 *** Pure ***
  3336 
  3337 * The 'class' package offers a combination of axclass and locale to
  3338 achieve Haskell-like type classes in Isabelle.  Definitions and
  3339 theorems within a class context produce both relative results (with
  3340 implicit parameters according to the locale context), and polymorphic
  3341 constants with qualified polymorphism (according to the class
  3342 context).  Within the body context of a 'class' target, a separate
  3343 syntax layer ("user space type system") takes care of converting
  3344 between global polymorphic consts and internal locale representation.
  3345 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  3346 "isatool doc classes" provides a tutorial.
  3347 
  3348 * Generic code generator framework allows to generate executable
  3349 code for ML and Haskell (including Isabelle classes).  A short usage
  3350 sketch:
  3351 
  3352     internal compilation:
  3353         export_code <list of constants (term syntax)> in SML
  3354     writing SML code to a file:
  3355         export_code <list of constants (term syntax)> in SML <filename>
  3356     writing OCaml code to a file:
  3357         export_code <list of constants (term syntax)> in OCaml <filename>
  3358     writing Haskell code to a bunch of files:
  3359         export_code <list of constants (term syntax)> in Haskell <filename>
  3360 
  3361     evaluating closed propositions to True/False using code generation:
  3362         method ``eval''
  3363 
  3364 Reasonable default setup of framework in HOL.
  3365 
  3366 Theorem attributs for selecting and transforming function equations theorems:
  3367 
  3368     [code fun]:        select a theorem as function equation for a specific constant
  3369     [code fun del]:    deselect a theorem as function equation for a specific constant
  3370     [code inline]:     select an equation theorem for unfolding (inlining) in place
  3371     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  3372 
  3373 User-defined serializations (target in {SML, OCaml, Haskell}):
  3374 
  3375     code_const <and-list of constants (term syntax)>
  3376       {(target) <and-list of const target syntax>}+
  3377 
  3378     code_type <and-list of type constructors>
  3379       {(target) <and-list of type target syntax>}+
  3380 
  3381     code_instance <and-list of instances>
  3382       {(target)}+
  3383         where instance ::= <type constructor> :: <class>
  3384 
  3385     code_class <and_list of classes>
  3386       {(target) <and-list of class target syntax>}+
  3387         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  3388 
  3389 code_instance and code_class only are effective to target Haskell.
  3390 
  3391 For example usage see src/HOL/ex/Codegenerator.thy and
  3392 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  3393 generation from Isabelle/HOL theories is available via "isatool doc
  3394 codegen".
  3395 
  3396 * Code generator: consts in 'consts_code' Isar commands are now
  3397 referred to by usual term syntax (including optional type
  3398 annotations).
  3399 
  3400 * Command 'no_translations' removes translation rules from theory
  3401 syntax.
  3402 
  3403 * Overloaded definitions are now actually checked for acyclic
  3404 dependencies.  The overloading scheme is slightly more general than
  3405 that of Haskell98, although Isabelle does not demand an exact
  3406 correspondence to type class and instance declarations.
  3407 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  3408 exotic versions of overloading -- at the discretion of the user!
  3409 
  3410 Polymorphic constants are represented via type arguments, i.e. the
  3411 instantiation that matches an instance against the most general
  3412 declaration given in the signature.  For example, with the declaration
  3413 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  3414 as c(nat).  Overloading is essentially simultaneous structural
  3415 recursion over such type arguments.  Incomplete specification patterns
  3416 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  3417 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  3418 Command 'print_theory' outputs the normalized system of recursive
  3419 equations, see section "definitions".
  3420 
  3421 * Configuration options are maintained within the theory or proof
  3422 context (with name and type bool/int/string), providing a very simple
  3423 interface to a poor-man's version of general context data.  Tools may
  3424 declare options in ML (e.g. using Attrib.config_int) and then refer to
  3425 these values using Config.get etc.  Users may change options via an
  3426 associated attribute of the same name.  This form of context
  3427 declaration works particularly well with commands 'declare' or
  3428 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  3429 very easy to avoid global references, which would not observe Isar
  3430 toplevel undo/redo and fail to work with multithreading.
  3431 
  3432 Various global ML references of Pure and HOL have been turned into
  3433 configuration options:
  3434 
  3435   Unify.search_bound		unify_search_bound
  3436   Unify.trace_bound		unify_trace_bound
  3437   Unify.trace_simp		unify_trace_simp
  3438   Unify.trace_types		unify_trace_types
  3439   Simplifier.simp_depth_limit	simp_depth_limit
  3440   Blast.depth_limit		blast_depth_limit
  3441   DatatypeProp.dtK		datatype_distinctness_limit
  3442   fast_arith_neq_limit  	fast_arith_neq_limit
  3443   fast_arith_split_limit	fast_arith_split_limit
  3444 
  3445 * Named collections of theorems may be easily installed as context
  3446 data using the functor NamedThmsFun (see also
  3447 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  3448 attributes; there is also a toplevel print command.  This facility is
  3449 just a common case of general context data, which is the preferred way
  3450 for anything more complex than just a list of facts in canonical
  3451 order.
  3452 
  3453 * Isar: command 'declaration' augments a local theory by generic
  3454 declaration functions written in ML.  This enables arbitrary content
  3455 being added to the context, depending on a morphism that tells the
  3456 difference of the original declaration context wrt. the application
  3457 context encountered later on.
  3458 
  3459 * Isar: proper interfaces for simplification procedures.  Command
  3460 'simproc_setup' declares named simprocs (with match patterns, and body
  3461 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  3462 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  3463 
  3464 * Isar: an extra pair of brackets around attribute declarations
  3465 abbreviates a theorem reference involving an internal dummy fact,
  3466 which will be ignored later --- only the effect of the attribute on
  3467 the background context will persist.  This form of in-place
  3468 declarations is particularly useful with commands like 'declare' and
  3469 'using', for example ``have A using [[simproc a]] by simp''.
  3470 
  3471 * Isar: method "assumption" (and implicit closing of subproofs) now
  3472 takes simple non-atomic goal assumptions into account: after applying
  3473 an assumption as a rule the resulting subgoals are solved by atomic
  3474 assumption steps.  This is particularly useful to finish 'obtain'
  3475 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  3476 without referring to the original premise "!!x. P x ==> thesis" in the
  3477 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  3478 more permissive.
  3479 
  3480 * Isar: implicit use of prems from the Isar proof context is
  3481 considered a legacy feature.  Common applications like ``have A .''
  3482 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  3483 referencing facts explicitly here improves readability and
  3484 maintainability of proof texts.
  3485 
  3486 * Isar: improper proof element 'guess' is like 'obtain', but derives
  3487 the obtained context from the course of reasoning!  For example:
  3488 
  3489   assume "EX x y. A x & B y"   -- "any previous fact"
  3490   then guess x and y by clarify
  3491 
  3492 This technique is potentially adventurous, depending on the facts and
  3493 proof tools being involved here.
  3494 
  3495 * Isar: known facts from the proof context may be specified as literal
  3496 propositions, using ASCII back-quote syntax.  This works wherever
  3497 named facts used to be allowed so far, in proof commands, proof
  3498 methods, attributes etc.  Literal facts are retrieved from the context
  3499 according to unification of type and term parameters.  For example,
  3500 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  3501 theorems in the current context, then these are valid literal facts:
  3502 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  3503 
  3504 There is also a proof method "fact" which does the same composition
  3505 for explicit goal states, e.g. the following proof texts coincide with
  3506 certain special cases of literal facts:
  3507 
  3508   have "A" by fact                 ==  note `A`
  3509   have "A ==> B" by fact           ==  note `A ==> B`
  3510   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  3511   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  3512 
  3513 * Isar: ":" (colon) is no longer a symbolic identifier character in
  3514 outer syntax.  Thus symbolic identifiers may be used without
  3515 additional white space in declarations like this: ``assume *: A''.
  3516 
  3517 * Isar: 'print_facts' prints all local facts of the current context,
  3518 both named and unnamed ones.
  3519 
  3520 * Isar: 'def' now admits simultaneous definitions, e.g.:
  3521 
  3522   def x == "t" and y == "u"
  3523 
  3524 * Isar: added command 'unfolding', which is structurally similar to
  3525 'using', but affects both the goal state and facts by unfolding given
  3526 rewrite rules.  Thus many occurrences of the 'unfold' method or
  3527 'unfolded' attribute may be replaced by first-class proof text.
  3528 
  3529 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  3530 and command 'unfolding' now all support object-level equalities
  3531 (potentially conditional).  The underlying notion of rewrite rule is
  3532 analogous to the 'rule_format' attribute, but *not* that of the
  3533 Simplifier (which is usually more generous).
  3534 
  3535 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  3536 premises of a theorem by n. Useful in conjunction with drule.
  3537 
  3538 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  3539 method expression within a sandbox consisting of the first N
  3540 sub-goals, which need to exist.  For example, ``simp_all [3]''
  3541 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  3542 simplifies all new goals that emerge from applying rule foo to the
  3543 originally first one.
  3544 
  3545 * Isar: schematic goals are no longer restricted to higher-order
  3546 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  3547 expected.
  3548 
  3549 * Isar: the conclusion of a long theorem statement is now either
  3550 'shows' (a simultaneous conjunction, as before), or 'obtains'
  3551 (essentially a disjunction of cases with local parameters and
  3552 assumptions).  The latter allows to express general elimination rules
  3553 adequately; in this notation common elimination rules look like this:
  3554 
  3555   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  3556     assumes "EX x. P x"
  3557     obtains x where "P x"
  3558 
  3559   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  3560     assumes "A & B"
  3561     obtains A and B
  3562 
  3563   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  3564     assumes "A | B"
  3565     obtains
  3566       A
  3567     | B
  3568 
  3569 The subsequent classical rules even refer to the formal "thesis"
  3570 explicitly:
  3571 
  3572   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  3573     obtains "~ thesis"
  3574 
  3575   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  3576     obtains "thesis ==> something"
  3577 
  3578 The actual proof of an 'obtains' statement is analogous to that of the
  3579 Isar proof element 'obtain', only that there may be several cases.
  3580 Optional case names may be specified in parentheses; these will be
  3581 available both in the present proof and as annotations in the
  3582 resulting rule, for later use with the 'cases' method (cf. attribute
  3583 case_names).
  3584 
  3585 * Isar: the assumptions of a long theorem statement are available as
  3586 "assms" fact in the proof context.  This is more appropriate than the
  3587 (historical) "prems", which refers to all assumptions of the current
  3588 context, including those from the target locale, proof body etc.
  3589 
  3590 * Isar: 'print_statement' prints theorems from the current theory or
  3591 proof context in long statement form, according to the syntax of a
  3592 top-level lemma.
  3593 
  3594 * Isar: 'obtain' takes an optional case name for the local context
  3595 introduction rule (default "that").
  3596 
  3597 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  3598 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  3599 to occur.
  3600 
  3601 * Pure: syntax "CONST name" produces a fully internalized constant
  3602 according to the current context.  This is particularly useful for
  3603 syntax translations that should refer to internal constant
  3604 representations independently of name spaces.
  3605 
  3606 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  3607 instead of "FOO ". This allows multiple binder declarations to coexist
  3608 in the same context.  INCOMPATIBILITY.
  3609 
  3610 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  3611 primitive that also works in a locale context (both for constants and
  3612 fixed variables). Type declaration and internal syntactic representation
  3613 of given constants retrieved from the context. Likewise, the
  3614 'no_notation' command allows to remove given syntax annotations from the
  3615 current context.
  3616 
  3617 * Isar/locales: new derived specification elements 'axiomatization',
  3618 'definition', 'abbreviation', which support type-inference, admit
  3619 object-level specifications (equality, equivalence).  See also the
  3620 isar-ref manual.  Examples:
  3621 
  3622   axiomatization
  3623     eq  (infix "===" 50) where
  3624     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  3625 
  3626   definition "f x y = x + y + 1"
  3627   definition g where "g x = f x x"
  3628 
  3629   abbreviation
  3630     neq  (infix "=!=" 50) where
  3631     "x =!= y == ~ (x === y)"
  3632 
  3633 These specifications may be also used in a locale context.  Then the
  3634 constants being introduced depend on certain fixed parameters, and the
  3635 constant name is qualified by the locale base name.  An internal
  3636 abbreviation takes care for convenient input and output, making the
  3637 parameters implicit and using the original short name.  See also
  3638 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  3639 entities from a monomorphic theory.
  3640 
  3641 Presently, abbreviations are only available 'in' a target locale, but
  3642 not inherited by general import expressions.  Also note that
  3643 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  3644 'translations' in common applications.  The "no_abbrevs" print mode
  3645 prevents folding of abbreviations in term output.
  3646 
  3647 Concrete syntax is attached to specified constants in internal form,
  3648 independently of name spaces.  The parse tree representation is
  3649 slightly different -- use 'notation' instead of raw 'syntax', and
  3650 'translations' with explicit "CONST" markup to accommodate this.
  3651 
  3652 * Pure/Isar: unified syntax for new-style specification mechanisms
  3653 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  3654 full type inference and dummy patterns ("_").  For example:
  3655 
  3656   definition "K x _ = x"
  3657 
  3658   inductive conj for A B
  3659   where "A ==> B ==> conj A B"
  3660 
  3661 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  3662 the current context.  Print mode "no_abbrevs" prevents inversion of
  3663 abbreviations on output.
  3664 
  3665 * Isar/locales: improved parameter handling: use of locales "var" and
  3666 "struct" no longer necessary; - parameter renamings are no longer
  3667 required to be injective.  For example, this allows to define
  3668 endomorphisms as locale endom = homom mult mult h.
  3669 
  3670 * Isar/locales: changed the way locales with predicates are defined.
  3671 Instead of accumulating the specification, the imported expression is
  3672 now an interpretation.  INCOMPATIBILITY: different normal form of
  3673 locale expressions.  In particular, in interpretations of locales with
  3674 predicates, goals repesenting already interpreted fragments are not
  3675 removed automatically.  Use methods `intro_locales' and
  3676 `unfold_locales'; see below.
  3677 
  3678 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  3679 provide backward reasoning on locales predicates.  The methods are
  3680 aware of interpretations and discharge corresponding goals.
  3681 `intro_locales' is less aggressive then `unfold_locales' and does not
  3682 unfold predicates to assumptions.
  3683 
  3684 * Isar/locales: the order in which locale fragments are accumulated
  3685 has changed.  This enables to override declarations from fragments due
  3686 to interpretations -- for example, unwanted simp rules.
  3687 
  3688 * Isar/locales: interpretation in theories and proof contexts has been
  3689 extended.  One may now specify (and prove) equations, which are
  3690 unfolded in interpreted theorems.  This is useful for replacing
  3691 defined concepts (constants depending on locale parameters) by
  3692 concepts already existing in the target context.  Example:
  3693 
  3694   interpretation partial_order ["op <= :: [int, int] => bool"]
  3695     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3696 
  3697 Typically, the constant `partial_order.less' is created by a
  3698 definition specification element in the context of locale
  3699 partial_order.
  3700 
  3701 * Method "induct": improved internal context management to support
  3702 local fixes and defines on-the-fly. Thus explicit meta-level
  3703 connectives !!  and ==> are rarely required anymore in inductive goals
  3704 (using object-logic connectives for this purpose has been long
  3705 obsolete anyway). Common proof patterns are explained in
  3706 src/HOL/Induct/Common_Patterns.thy, see also
  3707 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3708 examples.
  3709 
  3710 * Method "induct": improved handling of simultaneous goals. Instead of
  3711 introducing object-level conjunction, the statement is now split into
  3712 several conclusions, while the corresponding symbolic cases are nested
  3713 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3714 see src/HOL/Induct/Common_Patterns.thy, for example.
  3715 
  3716 * Method "induct": mutual induction rules are now specified as a list
  3717 of rule sharing the same induction cases. HOL packages usually provide
  3718 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3719 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3720 mutual induction rules differently, i.e. like this:
  3721 
  3722   (induct rule: foo_bar.inducts)
  3723   (induct set: foo bar)
  3724   (induct pred: foo bar)
  3725   (induct type: foo bar)
  3726 
  3727 The ML function ProjectRule.projections turns old-style rules into the
  3728 new format.
  3729 
  3730 * Method "coinduct": dual of induction, see
  3731 src/HOL/Library/Coinductive_List.thy for various examples.
  3732 
  3733 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3734 considered a legacy feature.
  3735 
  3736 * Attribute "symmetric" produces result with standardized schematic
  3737 variables (index 0).  Potential INCOMPATIBILITY.
  3738 
  3739 * Simplifier: by default the simplifier trace only shows top level
  3740 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3741 default. Thus there is less danger of being flooded by the trace. The
  3742 trace indicates where parts have been suppressed.
  3743   
  3744 * Provers/classical: removed obsolete classical version of elim_format
  3745 attribute; classical elim/dest rules are now treated uniformly when
  3746 manipulating the claset.
  3747 
  3748 * Provers/classical: stricter checks to ensure that supplied intro,
  3749 dest and elim rules are well-formed; dest and elim rules must have at
  3750 least one premise.
  3751 
  3752 * Provers/classical: attributes dest/elim/intro take an optional
  3753 weight argument for the rule (just as the Pure versions).  Weights are
  3754 ignored by automated tools, but determine the search order of single
  3755 rule steps.
  3756 
  3757 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3758 where the body does not mention the bound variable.  Note that dummy
  3759 patterns implicitly depend on their context of bounds, which makes
  3760 "{_. _}" match any set comprehension as expected.  Potential
  3761 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3762 constant "_idtdummy" in the binding position.
  3763 
  3764 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3765 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3766 for example "A -> B" => "Pi A (%_. B)".
  3767 
  3768 * Pure: 'class_deps' command visualizes the subclass relation, using
  3769 the graph browser tool.
  3770 
  3771 * Pure: 'print_theory' now suppresses certain internal declarations by
  3772 default; use '!' option for full details.
  3773 
  3774 
  3775 *** HOL ***
  3776 
  3777 * Method "metis" proves goals by applying the Metis general-purpose
  3778 resolution prover (see also http://gilith.com/software/metis/).
  3779 Examples are in the directory MetisExamples.  WARNING: the
  3780 Isabelle/HOL-Metis integration does not yet work properly with
  3781 multi-threading.
  3782   
  3783 * Command 'sledgehammer' invokes external automatic theorem provers as
  3784 background processes.  It generates calls to the "metis" method if
  3785 successful. These can be pasted into the proof.  Users do not have to
  3786 wait for the automatic provers to return.  WARNING: does not really
  3787 work with multi-threading.
  3788 
  3789 * New "auto_quickcheck" feature tests outermost goal statements for
  3790 potential counter-examples.  Controlled by ML references
  3791 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3792 5000 milliseconds).  Fails silently if statements is outside of
  3793 executable fragment, or any other codgenerator problem occurs.
  3794 
  3795 * New constant "undefined" with axiom "undefined x = undefined".
  3796 
  3797 * Added class "HOL.eq", allowing for code generation with polymorphic
  3798 equality.
  3799 
  3800 * Some renaming of class constants due to canonical name prefixing in
  3801 the new 'class' package:
  3802 
  3803     HOL.abs ~> HOL.abs_class.abs
  3804     HOL.divide ~> HOL.divide_class.divide
  3805     0 ~> HOL.zero_class.zero
  3806     1 ~> HOL.one_class.one
  3807     op + ~> HOL.plus_class.plus
  3808     op - ~> HOL.minus_class.minus
  3809     uminus ~> HOL.minus_class.uminus
  3810     op * ~> HOL.times_class.times
  3811     op < ~> HOL.ord_class.less
  3812     op <= > HOL.ord_class.less_eq
  3813     Nat.power ~> Power.power_class.power
  3814     Nat.size ~> Nat.size_class.size
  3815     Numeral.number_of ~> Numeral.number_class.number_of
  3816     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3817     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3818     Orderings.min ~> Orderings.ord_class.min
  3819     Orderings.max ~> Orderings.ord_class.max
  3820     Divides.op div ~> Divides.div_class.div
  3821     Divides.op mod ~> Divides.div_class.mod
  3822     Divides.op dvd ~> Divides.div_class.dvd
  3823 
  3824 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3825 
  3826 a) User-defined constants using any of the names "plus", "minus",
  3827 "times", "less" or "less_eq". The standard syntax translations for
  3828 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3829 names.
  3830 
  3831 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3832 INCOMPATIBILITY: use more specific names.
  3833 
  3834 c) Permutative equations (e.g. "a + b = b + a")
  3835 Since the change of names also changes the order of terms, permutative
  3836 rewrite rules may get applied in a different order. Experience shows
  3837 that this is rarely the case (only two adaptions in the whole Isabelle
  3838 distribution).  INCOMPATIBILITY: rewrite proofs
  3839 
  3840 d) ML code directly refering to constant names
  3841 This in general only affects hand-written proof tactics, simprocs and
  3842 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3843 Consider using @{const_name} antiquotation.
  3844 
  3845 * New class "default" with associated constant "default".
  3846 
  3847 * Function "sgn" is now overloaded and available on int, real, complex
  3848 (and other numeric types), using class "sgn".  Two possible defs of
  3849 sgn are given as equational assumptions in the classes sgn_if and
  3850 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3851 INCOMPATIBILITY.
  3852 
  3853 * Locale "partial_order" now unified with class "order" (cf. theory
  3854 Orderings), added parameter "less".  INCOMPATIBILITY.
  3855 
  3856 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3857 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3858 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3859 
  3860 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3861 changed order of proof goals in instance proofs.
  3862 
  3863 * The transitivity reasoner for partial and linear orders is set up
  3864 for classes "order" and "linorder".  Instances of the reasoner are available
  3865 in all contexts importing or interpreting the corresponding locales.
  3866 Method "order" invokes the reasoner separately; the reasoner
  3867 is also integrated with the Simplifier as a solver.  Diagnostic
  3868 command 'print_orders' shows the available instances of the reasoner
  3869 in the current context.
  3870 
  3871 * Localized monotonicity predicate in theory "Orderings"; integrated
  3872 lemmas max_of_mono and min_of_mono with this predicate.
  3873 INCOMPATIBILITY.
  3874 
  3875 * Formulation of theorem "dense" changed slightly due to integration
  3876 with new class dense_linear_order.
  3877 
  3878 * Uniform lattice theory development in HOL.
  3879 
  3880     constants "meet" and "join" now named "inf" and "sup"
  3881     constant "Meet" now named "Inf"
  3882 
  3883     classes "meet_semilorder" and "join_semilorder" now named
  3884       "lower_semilattice" and "upper_semilattice"
  3885     class "lorder" now named "lattice"
  3886     class "comp_lat" now named "complete_lattice"
  3887 
  3888     Instantiation of lattice classes allows explicit definitions
  3889     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3890 
  3891   INCOMPATIBILITY.  Theorem renames:
  3892 
  3893     meet_left_le            ~> inf_le1
  3894     meet_right_le           ~> inf_le2
  3895     join_left_le            ~> sup_ge1
  3896     join_right_le           ~> sup_ge2
  3897     meet_join_le            ~> inf_sup_ord
  3898     le_meetI                ~> le_infI
  3899     join_leI                ~> le_supI
  3900     le_meet                 ~> le_inf_iff
  3901     le_join                 ~> ge_sup_conv
  3902     meet_idempotent         ~> inf_idem
  3903     join_idempotent         ~> sup_idem
  3904     meet_comm               ~> inf_commute
  3905     join_comm               ~> sup_commute
  3906     meet_leI1               ~> le_infI1
  3907     meet_leI2               ~> le_infI2
  3908     le_joinI1               ~> le_supI1
  3909     le_joinI2               ~> le_supI2
  3910     meet_assoc              ~> inf_assoc
  3911     join_assoc              ~> sup_assoc
  3912     meet_left_comm          ~> inf_left_commute
  3913     meet_left_idempotent    ~> inf_left_idem
  3914     join_left_comm          ~> sup_left_commute
  3915     join_left_idempotent    ~> sup_left_idem
  3916     meet_aci                ~> inf_aci
  3917     join_aci                ~> sup_aci
  3918     le_def_meet             ~> le_iff_inf
  3919     le_def_join             ~> le_iff_sup
  3920     join_absorp2            ~> sup_absorb2
  3921     join_absorp1            ~> sup_absorb1
  3922     meet_absorp1            ~> inf_absorb1
  3923     meet_absorp2            ~> inf_absorb2
  3924     meet_join_absorp        ~> inf_sup_absorb
  3925     join_meet_absorp        ~> sup_inf_absorb
  3926     distrib_join_le         ~> distrib_sup_le
  3927     distrib_meet_le         ~> distrib_inf_le
  3928 
  3929     add_meet_distrib_left   ~> add_inf_distrib_left
  3930     add_join_distrib_left   ~> add_sup_distrib_left
  3931     is_join_neg_meet        ~> is_join_neg_inf
  3932     is_meet_neg_join        ~> is_meet_neg_sup
  3933     add_meet_distrib_right  ~> add_inf_distrib_right
  3934     add_join_distrib_right  ~> add_sup_distrib_right
  3935     add_meet_join_distribs  ~> add_sup_inf_distribs
  3936     join_eq_neg_meet        ~> sup_eq_neg_inf
  3937     meet_eq_neg_join        ~> inf_eq_neg_sup
  3938     add_eq_meet_join        ~> add_eq_inf_sup
  3939     meet_0_imp_0            ~> inf_0_imp_0
  3940     join_0_imp_0            ~> sup_0_imp_0
  3941     meet_0_eq_0             ~> inf_0_eq_0
  3942     join_0_eq_0             ~> sup_0_eq_0
  3943     neg_meet_eq_join        ~> neg_inf_eq_sup
  3944     neg_join_eq_meet        ~> neg_sup_eq_inf
  3945     join_eq_if              ~> sup_eq_if
  3946 
  3947     mono_meet               ~> mono_inf
  3948     mono_join               ~> mono_sup
  3949     meet_bool_eq            ~> inf_bool_eq
  3950     join_bool_eq            ~> sup_bool_eq
  3951     meet_fun_eq             ~> inf_fun_eq
  3952     join_fun_eq             ~> sup_fun_eq
  3953     meet_set_eq             ~> inf_set_eq
  3954     join_set_eq             ~> sup_set_eq
  3955     meet1_iff               ~> inf1_iff
  3956     meet2_iff               ~> inf2_iff
  3957     meet1I                  ~> inf1I
  3958     meet2I                  ~> inf2I
  3959     meet1D1                 ~> inf1D1
  3960     meet2D1                 ~> inf2D1
  3961     meet1D2                 ~> inf1D2
  3962     meet2D2                 ~> inf2D2
  3963     meet1E                  ~> inf1E
  3964     meet2E                  ~> inf2E
  3965     join1_iff               ~> sup1_iff
  3966     join2_iff               ~> sup2_iff
  3967     join1I1                 ~> sup1I1
  3968     join2I1                 ~> sup2I1
  3969     join1I1                 ~> sup1I1
  3970     join2I2                 ~> sup1I2
  3971     join1CI                 ~> sup1CI
  3972     join2CI                 ~> sup2CI
  3973     join1E                  ~> sup1E
  3974     join2E                  ~> sup2E
  3975 
  3976     is_meet_Meet            ~> is_meet_Inf
  3977     Meet_bool_def           ~> Inf_bool_def
  3978     Meet_fun_def            ~> Inf_fun_def
  3979     Meet_greatest           ~> Inf_greatest
  3980     Meet_lower              ~> Inf_lower
  3981     Meet_set_def            ~> Inf_set_def
  3982 
  3983     Sup_def                 ~> Sup_Inf
  3984     Sup_bool_eq             ~> Sup_bool_def
  3985     Sup_fun_eq              ~> Sup_fun_def
  3986     Sup_set_eq              ~> Sup_set_def
  3987 
  3988     listsp_meetI            ~> listsp_infI
  3989     listsp_meet_eq          ~> listsp_inf_eq
  3990 
  3991     meet_min                ~> inf_min
  3992     join_max                ~> sup_max
  3993 
  3994 * Added syntactic class "size"; overloaded constant "size" now has
  3995 type "'a::size ==> bool"
  3996 
  3997 * Internal reorganisation of `size' of datatypes: size theorems
  3998 "foo.size" are no longer subsumed by "foo.simps" (but are still
  3999 simplification rules by default!); theorems "prod.size" now named
  4000 "*.size".
  4001 
  4002 * Class "div" now inherits from class "times" rather than "type".
  4003 INCOMPATIBILITY.
  4004 
  4005 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  4006 Linorder etc.  have disappeared; operations defined in terms of
  4007 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  4008 
  4009 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  4010 
  4011 * HOL-Word: New extensive library and type for generic, fixed size
  4012 machine words, with arithemtic, bit-wise, shifting and rotating
  4013 operations, reflection into int, nat, and bool lists, automation for
  4014 linear arithmetic (by automatic reflection into nat or int), including
  4015 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  4016 arithmetic type classes, supporting automatic simplification of
  4017 numerals on all operations.
  4018 
  4019 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  4020 
  4021 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  4022 
  4023 * Code generator library theories:
  4024   - Code_Integer represents HOL integers by big integer literals in target
  4025     languages.
  4026   - Code_Char represents HOL characters by character literals in target
  4027     languages.
  4028   - Code_Char_chr like Code_Char, but also offers treatment of character
  4029     codes; includes Code_Integer.
  4030   - Executable_Set allows to generate code for finite sets using lists.
  4031   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  4032     denominator).
  4033   - Executable_Real implements a subset of real numbers, namly those
  4034     representable by rational numbers.
  4035   - Efficient_Nat implements natural numbers by integers, which in general will
  4036     result in higher efficency; pattern matching with 0/Suc is eliminated;
  4037     includes Code_Integer.
  4038   - Code_Index provides an additional datatype index which is mapped to
  4039     target-language built-in integers.
  4040   - Code_Message provides an additional datatype message_string which is isomorphic to
  4041     strings; messages are mapped to target-language strings.
  4042 
  4043 * New package for inductive predicates
  4044 
  4045   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  4046 
  4047     inductive
  4048       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4049       for z_1 :: U_1 and ... and z_n :: U_m
  4050     where
  4051       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4052     | ...
  4053 
  4054   with full support for type-inference, rather than
  4055 
  4056     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4057 
  4058     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4059     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4060 
  4061     inductive "s z_1 ... z_m"
  4062     intros
  4063       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4064       ...
  4065 
  4066   For backward compatibility, there is a wrapper allowing inductive
  4067   sets to be defined with the new package via
  4068 
  4069     inductive_set
  4070       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4071       for z_1 :: U_1 and ... and z_n :: U_m
  4072     where
  4073       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4074     | ...
  4075 
  4076   or
  4077 
  4078     inductive_set
  4079       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4080       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4081       for z_1 :: U_1 and ... and z_n :: U_m
  4082     where
  4083       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4084     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4085     | ...
  4086 
  4087   if the additional syntax "p ..." is required.
  4088 
  4089   Numerous examples can be found in the subdirectories src/HOL/Auth,
  4090   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  4091 
  4092   INCOMPATIBILITIES:
  4093 
  4094   - Since declaration and definition of inductive sets or predicates
  4095     is no longer separated, abbreviations involving the newly
  4096     introduced sets or predicates must be specified together with the
  4097     introduction rules after the 'where' keyword (see above), rather
  4098     than before the actual inductive definition.
  4099 
  4100   - The variables in induction and elimination rules are now
  4101     quantified in the order of their occurrence in the introduction
  4102     rules, rather than in alphabetical order. Since this may break
  4103     some proofs, these proofs either have to be repaired, e.g. by
  4104     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  4105     statements of the form
  4106 
  4107       case (rule_i a_i_1 ... a_i_{k_i})
  4108 
  4109     or the old order of quantification has to be restored by explicitly adding
  4110     meta-level quantifiers in the introduction rules, i.e.
  4111 
  4112       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  4113 
  4114   - The format of the elimination rules is now
  4115 
  4116       p z_1 ... z_m x_1 ... x_n ==>
  4117         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4118         ==> ... ==> P
  4119 
  4120     for predicates and
  4121 
  4122       (x_1, ..., x_n) : s z_1 ... z_m ==>
  4123         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4124         ==> ... ==> P
  4125 
  4126     for sets rather than
  4127 
  4128       x : s z_1 ... z_m ==>
  4129         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  4130         ==> ... ==> P
  4131 
  4132     This may require terms in goals to be expanded to n-tuples
  4133     (e.g. using case_tac or simplification with the split_paired_all
  4134     rule) before the above elimination rule is applicable.
  4135 
  4136   - The elimination or case analysis rules for (mutually) inductive
  4137     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  4138     list of rules "p_1_..._p_k.elims" is no longer available.
  4139 
  4140 * New package "function"/"fun" for general recursive functions,
  4141 supporting mutual and nested recursion, definitions in local contexts,
  4142 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  4143 for small examples, and the separate tutorial on the function
  4144 package. The old recdef "package" is still available as before, but
  4145 users are encouraged to use the new package.
  4146 
  4147 * Method "lexicographic_order" automatically synthesizes termination
  4148 relations as lexicographic combinations of size measures. 
  4149 
  4150 * Case-expressions allow arbitrary constructor-patterns (including
  4151 "_") and take their order into account, like in functional
  4152 programming.  Internally, this is translated into nested
  4153 case-expressions; missing cases are added and mapped to the predefined
  4154 constant "undefined". In complicated cases printing may no longer show
  4155 the original input but the internal form. Lambda-abstractions allow
  4156 the same form of pattern matching: "% pat1 => e1 | ..." is an
  4157 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  4158 variable.
  4159 
  4160 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  4161 is an abbreviation for "of_nat :: nat => int". The simplification
  4162 rules for "of_nat" have been changed to work like "int" did
  4163 previously.  Potential INCOMPATIBILITY:
  4164   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  4165   - of_nat_diff and of_nat_mult are no longer default simp rules
  4166 
  4167 * Method "algebra" solves polynomial equations over (semi)rings using
  4168 Groebner bases. The (semi)ring structure is defined by locales and the
  4169 tool setup depends on that generic context. Installing the method for
  4170 a specific type involves instantiating the locale and possibly adding
  4171 declarations for computation on the coefficients.  The method is
  4172 already instantiated for natural numbers and for the axiomatic class
  4173 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  4174 CALCULEMUS 2007 for the general principles underlying this
  4175 architecture of context-aware proof-tools.
  4176 
  4177 * Method "ferrack" implements quantifier elimination over
  4178 special-purpose dense linear orders using locales (analogous to
  4179 "algebra"). The method is already installed for class
  4180 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  4181 rat, etc.
  4182 
  4183 * Former constant "List.op @" now named "List.append".  Use ML
  4184 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  4185 circumvent possible incompatibilities when working on ML level.
  4186 
  4187 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  4188 
  4189 * New function listsum :: 'a list => 'a for arbitrary monoids.
  4190 Special syntax: "SUM x <- xs. f x" (and latex variants)
  4191 
  4192 * New syntax for Haskell-like list comprehension (input only), eg.
  4193 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  4194 
  4195 * The special syntax for function "filter" has changed from [x :
  4196 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  4197 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  4198 
  4199 * [a..b] is now defined for arbitrary linear orders.  It used to be
  4200 defined on nat only, as an abbreviation for [a..<Suc b]
  4201 INCOMPATIBILITY.
  4202 
  4203 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  4204 
  4205 * New functions "sorted" and "sort" in src/HOL/List.thy.
  4206 
  4207 * New lemma collection field_simps (an extension of ring_simps) for
  4208 manipulating (in)equations involving division. Multiplies with all
  4209 denominators that can be proved to be non-zero (in equations) or
  4210 positive/negative (in inequations).
  4211 
  4212 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  4213 have been improved and renamed to ring_simps, group_simps and
  4214 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  4215 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  4216 
  4217 * Theory Library/Commutative_Ring: switched from recdef to function
  4218 package; constants add, mul, pow now curried.  Infix syntax for
  4219 algebraic operations.
  4220 
  4221 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  4222 INCOMPATIBILITY.
  4223 
  4224 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  4225 INCOMPATIBILITY.
  4226 
  4227 * HOL/records: generalised field-update to take a function on the
  4228 field rather than the new value: r(|A := x|) is translated to A_update
  4229 (K x) r The K-combinator that is internally used is called K_record.
  4230 INCOMPATIBILITY: Usage of the plain update functions has to be
  4231 adapted.
  4232  
  4233 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  4234 * x = 0, which are required for a semiring.  Richer structures do not
  4235 inherit from semiring_0 anymore, because this property is a theorem
  4236 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  4237 there is more to prove, but this is mostly trivial.
  4238 
  4239 * Class "recpower" is generalized to arbitrary monoids, not just
  4240 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  4241 commutativity or semiring properties additionally.
  4242 
  4243 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  4244 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  4245 better use 'abbreviation'.
  4246 
  4247 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  4248 
  4249 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  4250 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  4251 significant changes for setting up numeral syntax for types:
  4252   - New constants Numeral.pred and Numeral.succ instead
  4253       of former Numeral.bin_pred and Numeral.bin_succ.
  4254   - Use integer operations instead of bin_add, bin_mult and so on.
  4255   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  4256   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  4257 
  4258 See src/HOL/Integ/IntArith.thy for an example setup.
  4259 
  4260 * Command 'normal_form' computes the normal form of a term that may
  4261 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  4262 produces ``[b, c, a]'' (without proof).  This command is suitable for
  4263 heavy-duty computations because the functions are compiled to ML
  4264 first.  Correspondingly, a method "normalization" is provided.  See
  4265 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  4266 
  4267 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  4268 25 like -->); output depends on the "iff" print_mode, the default is
  4269 "A = B" (with priority 50).
  4270 
  4271 * Relations less (<) and less_eq (<=) are also available on type bool.
  4272 Modified syntax to disallow nesting without explicit parentheses,
  4273 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  4274 INCOMPATIBILITY.
  4275 
  4276 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  4277 
  4278 * Relation composition operator "op O" now has precedence 75 and binds
  4279 stronger than union and intersection. INCOMPATIBILITY.
  4280 
  4281 * The old set interval syntax "{m..n(}" (and relatives) has been
  4282 removed.  Use "{m..<n}" (and relatives) instead.
  4283 
  4284 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  4285 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  4286 ``declare [[simproc del: neq]]''.
  4287 
  4288 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  4289 True/False.
  4290 
  4291 * Theorem Cons_eq_map_conv no longer declared as "simp".
  4292 
  4293 * Theorem setsum_mult renamed to setsum_right_distrib.
  4294 
  4295 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  4296 ``rule'' method.
  4297 
  4298 * Reimplemented methods "sat" and "satx", with several improvements:
  4299 goals no longer need to be stated as "<prems> ==> False", equivalences
  4300 (i.e. "=" on type bool) are handled, variable names of the form
  4301 "lit_<n>" are no longer reserved, significant speedup.
  4302 
  4303 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  4304 zChaff is still supported as well.
  4305 
  4306 * 'inductive' and 'datatype': provide projections of mutual rules,
  4307 bundled as foo_bar.inducts;
  4308 
  4309 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  4310 Library.
  4311 
  4312 * Library: moved theory Accessible_Part to main HOL.
  4313 
  4314 * Library: added theory Coinductive_List of potentially infinite lists
  4315 as greatest fixed-point.
  4316 
  4317 * Library: added theory AssocList which implements (finite) maps as
  4318 association lists.
  4319 
  4320 * Method "evaluation" solves goals (i.e. a boolean expression)
  4321 efficiently by compiling it to ML.  The goal is "proved" (via an
  4322 oracle) if it evaluates to True.
  4323 
  4324 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  4325 also when invoked by the simplifier.  This results in the Simplifier
  4326 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  4327 Configuration option fast_arith_split_limit=0 recovers the old
  4328 behavior.
  4329 
  4330 * Support for hex (0x20) and binary (0b1001) numerals.
  4331 
  4332 * New method: reify eqs (t), where eqs are equations for an
  4333 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  4334 parameter, computes a term s::'b and a list xs::'a list and proves the
  4335 theorem I xs s = t. This is also known as reification or quoting. The
  4336 resulting theorem is applied to the subgoal to substitute t with I xs
  4337 s.  If t is omitted, the subgoal itself is reified.
  4338 
  4339 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  4340 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  4341 where f is supposed to be a computable function (in the sense of code
  4342 generattion). The method uses reify to compute s and xs as above then
  4343 applies corr_thm and uses normalization by evaluation to "prove" f s =
  4344 r and finally gets the theorem t = r, which is again applied to the
  4345 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  4346 
  4347 * Reflection: Automatic reification now handels binding, an example is
  4348 available in src/HOL/ex/ReflectionEx.thy
  4349 
  4350 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  4351 command 'statespace' that is similar to 'record', but introduces an
  4352 abstract specification based on the locale infrastructure instead of
  4353 HOL types.  This leads to extra flexibility in composing state spaces,
  4354 in particular multiple inheritance and renaming of components.
  4355 
  4356 
  4357 *** HOL-Complex ***
  4358 
  4359 * Hyperreal: Functions root and sqrt are now defined on negative real
  4360 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  4361 Nonnegativity side conditions have been removed from many lemmas, so
  4362 that more subgoals may now be solved by simplification; potential
  4363 INCOMPATIBILITY.
  4364 
  4365 * Real: new type classes formalize real normed vector spaces and
  4366 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  4367 and norm :: 'a => real.
  4368 
  4369 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  4370 reals into other types. The overloaded constant Reals :: 'a set is now
  4371 defined as range of_real; potential INCOMPATIBILITY.
  4372 
  4373 * Real: proper support for ML code generation, including 'quickcheck'.
  4374 Reals are implemented as arbitrary precision rationals.
  4375 
  4376 * Hyperreal: Several constants that previously worked only for the
  4377 reals have been generalized, so they now work over arbitrary vector
  4378 spaces. Type annotations may need to be added in some cases; potential
  4379 INCOMPATIBILITY.
  4380 
  4381   Infinitesimal  :: ('a::real_normed_vector) star set
  4382   HFinite        :: ('a::real_normed_vector) star set
  4383   HInfinite      :: ('a::real_normed_vector) star set
  4384   approx         :: ('a::real_normed_vector) star => 'a star => bool
  4385   monad          :: ('a::real_normed_vector) star => 'a star set
  4386   galaxy         :: ('a::real_normed_vector) star => 'a star set
  4387   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  4388   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  4389   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  4390   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  4391   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  4392   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  4393   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  4394   sgn            :: 'a::real_normed_vector => 'a
  4395   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  4396 
  4397 * Complex: Some complex-specific constants are now abbreviations for
  4398 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  4399 hnorm.  Other constants have been entirely removed in favor of the
  4400 polymorphic versions (INCOMPATIBILITY):
  4401 
  4402   approx        <-- capprox
  4403   HFinite       <-- CFinite
  4404   HInfinite     <-- CInfinite
  4405   Infinitesimal <-- CInfinitesimal
  4406   monad         <-- cmonad
  4407   galaxy        <-- cgalaxy
  4408   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  4409   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  4410   (ns)deriv     <-- (ns)cderiv
  4411 
  4412 
  4413 *** HOL-Algebra ***
  4414 
  4415 * Formalisation of ideals and the quotient construction over rings.
  4416 
  4417 * Order and lattice theory no longer based on records.
  4418 INCOMPATIBILITY.
  4419 
  4420 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  4421 greatest_closed.  INCOMPATIBILITY.
  4422 
  4423 * Method algebra is now set up via an attribute.  For examples see
  4424 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  4425 of algebraic structures.
  4426 
  4427 * Renamed theory CRing to Ring.
  4428 
  4429 
  4430 *** HOL-Nominal ***
  4431 
  4432 * Substantial, yet incomplete support for nominal datatypes (binding
  4433 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  4434 src/HOL/Nominal/Examples.  Prospective users should consult
  4435 http://isabelle.in.tum.de/nominal/
  4436 
  4437 
  4438 *** ML ***
  4439 
  4440 * ML basics: just one true type int, which coincides with IntInf.int
  4441 (even on SML/NJ).
  4442 
  4443 * ML within Isar: antiquotations allow to embed statically-checked
  4444 formal entities in the source, referring to the context available at
  4445 compile-time.  For example:
  4446 
  4447 ML {* @{sort "{zero,one}"} *}
  4448 ML {* @{typ "'a => 'b"} *}
  4449 ML {* @{term "%x. x"} *}
  4450 ML {* @{prop "x == y"} *}
  4451 ML {* @{ctyp "'a => 'b"} *}
  4452 ML {* @{cterm "%x. x"} *}
  4453 ML {* @{cprop "x == y"} *}
  4454 ML {* @{thm asm_rl} *}
  4455 ML {* @{thms asm_rl} *}
  4456 ML {* @{type_name c} *}
  4457 ML {* @{type_syntax c} *}
  4458 ML {* @{const_name c} *}
  4459 ML {* @{const_syntax c} *}
  4460 ML {* @{context} *}
  4461 ML {* @{theory} *}
  4462 ML {* @{theory Pure} *}
  4463 ML {* @{theory_ref} *}
  4464 ML {* @{theory_ref Pure} *}
  4465 ML {* @{simpset} *}
  4466 ML {* @{claset} *}
  4467 ML {* @{clasimpset} *}
  4468 
  4469 The same works for sources being ``used'' within an Isar context.
  4470 
  4471 * ML in Isar: improved error reporting; extra verbosity with
  4472 ML_Context.trace enabled.
  4473 
  4474 * Pure/General/table.ML: the join operations now works via exceptions
  4475 DUP/SAME instead of type option. This is simpler in simple cases, and
  4476 admits slightly more efficient complex applications.
  4477 
  4478 * Pure: 'advanced' translation functions (parse_translation etc.) now
  4479 use Context.generic instead of just theory.
  4480 
  4481 * Pure: datatype Context.generic joins theory/Proof.context and
  4482 provides some facilities for code that works in either kind of
  4483 context, notably GenericDataFun for uniform theory and proof data.
  4484 
  4485 * Pure: simplified internal attribute type, which is now always
  4486 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  4487 local (Proof.context) attributes have been discontinued, while
  4488 minimizing code duplication. Thm.rule_attribute and
  4489 Thm.declaration_attribute build canonical attributes; see also structure
  4490 Context for further operations on Context.generic, notably
  4491 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  4492 declarations and definitions.
  4493 
  4494 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  4495 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  4496 init only required for impure data. INCOMPATIBILITY: empty really need
  4497 to be empty (no dependencies on theory content!)
  4498 
  4499 * Pure/kernel: consts certification ignores sort constraints given in
  4500 signature declarations. (This information is not relevant to the
  4501 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  4502 potential INCOMPATIBILITY.
  4503 
  4504 * Pure: axiomatic type classes are now purely definitional, with
  4505 explicit proofs of class axioms and super class relations performed
  4506 internally. See Pure/axclass.ML for the main internal interfaces --
  4507 notably AxClass.define_class supercedes AxClass.add_axclass, and
  4508 AxClass.axiomatize_class/classrel/arity supersede
  4509 Sign.add_classes/classrel/arities.
  4510 
  4511 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  4512 global/local versions on theory vs. Proof.context have been
  4513 discontinued; Attrib.syntax and Method.syntax have been adapted
  4514 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  4515 attributes, methods, etc.
  4516 
  4517 * Pure: several functions of signature "... -> theory -> theory * ..."
  4518 have been reoriented to "... -> theory -> ... * theory" in order to
  4519 allow natural usage in combination with the ||>, ||>>, |-> and
  4520 fold_map combinators.
  4521 
  4522 * Pure: official theorem names (closed derivations) and additional
  4523 comments (tags) are now strictly separate.  Name hints -- which are
  4524 maintained as tags -- may be attached any time without affecting the
  4525 derivation.
  4526 
  4527 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  4528 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  4529 achieve the old behaviour.
  4530 
  4531 * Pure: the "Goal" constant is now called "prop", supporting a
  4532 slightly more general idea of ``protecting'' meta-level rule
  4533 statements.
  4534 
  4535 * Pure: Logic.(un)varify only works in a global context, which is now
  4536 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  4537 Logic.legacy_(un)varify as temporary workaround.
  4538 
  4539 * Pure: structure Name provides scalable operations for generating
  4540 internal variable names, notably Name.variants etc.  This replaces
  4541 some popular functions from term.ML:
  4542 
  4543   Term.variant		->  Name.variant
  4544   Term.variantlist	->  Name.variant_list
  4545   Term.invent_names	->  Name.invent_list
  4546 
  4547 Note that low-level renaming rarely occurs in new code -- operations
  4548 from structure Variable are used instead (see below).
  4549 
  4550 * Pure: structure Variable provides fundamental operations for proper
  4551 treatment of fixed/schematic variables in a context.  For example,
  4552 Variable.import introduces fixes for schematics of given facts and
  4553 Variable.export reverses the effect (up to renaming) -- this replaces
  4554 various freeze_thaw operations.
  4555 
  4556 * Pure: structure Goal provides simple interfaces for
  4557 init/conclude/finish and tactical prove operations (replacing former
  4558 Tactic.prove).  Goal.prove is the canonical way to prove results
  4559 within a given context; Goal.prove_global is a degraded version for
  4560 theory level goals, including a global Drule.standard.  Note that
  4561 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  4562 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  4563 in a locale context).
  4564 
  4565 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  4566 and type checking (Syntax.check_term etc.), with common combinations
  4567 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  4568 which are considered legacy and await removal.
  4569 
  4570 * Pure/Syntax: generic interfaces for type unchecking
  4571 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  4572 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  4573 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  4574 available for convenience, but refer to the very same operations using
  4575 a mere theory instead of a full context.
  4576 
  4577 * Isar: simplified treatment of user-level errors, using exception
  4578 ERROR of string uniformly.  Function error now merely raises ERROR,
  4579 without any side effect on output channels.  The Isar toplevel takes
  4580 care of proper display of ERROR exceptions.  ML code may use plain
  4581 handle/can/try; cat_error may be used to concatenate errors like this:
  4582 
  4583   ... handle ERROR msg => cat_error msg "..."
  4584 
  4585 Toplevel ML code (run directly or through the Isar toplevel) may be
  4586 embedded into the Isar toplevel with exception display/debug like
  4587 this:
  4588 
  4589   Isar.toplevel (fn () => ...)
  4590 
  4591 INCOMPATIBILITY, removed special transform_error facilities, removed
  4592 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  4593 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  4594 -- use plain ERROR instead.
  4595 
  4596 * Isar: theory setup now has type (theory -> theory), instead of a
  4597 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  4598 
  4599 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  4600 ProofContext.debug/verbose flags.
  4601 
  4602 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  4603 theory before entering a proof state.  Transactions now always see a
  4604 quasi-functional intermediate checkpoint, both in interactive and
  4605 batch mode.
  4606 
  4607 * Isar: simplified interfaces for outer syntax.  Renamed
  4608 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  4609 OuterSyntax.add_parsers -- this functionality is now included in
  4610 OuterSyntax.command etc.  INCOMPATIBILITY.
  4611 
  4612 * Simplifier: the simpset of a running simplification process now
  4613 contains a proof context (cf. Simplifier.the_context), which is the
  4614 very context that the initial simpset has been retrieved from (by
  4615 simpset_of/local_simpset_of).  Consequently, all plug-in components
  4616 (solver, looper etc.) may depend on arbitrary proof data.
  4617 
  4618 * Simplifier.inherit_context inherits the proof context (plus the
  4619 local bounds) of the current simplification process; any simproc
  4620 etc. that calls the Simplifier recursively should do this!  Removed
  4621 former Simplifier.inherit_bounds, which is already included here --
  4622 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  4623 specify an explicit context using Simplifier.context/theory_context.
  4624 
  4625 * Simplifier/Classical Reasoner: more abstract interfaces
  4626 change_simpset/claset for modifying the simpset/claset reference of a
  4627 theory; raw versions simpset/claset_ref etc. have been discontinued --
  4628 INCOMPATIBILITY.
  4629 
  4630 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  4631 "Trueprop" etc.
  4632 
  4633 
  4634 *** System ***
  4635 
  4636 * settings: the default heap location within ISABELLE_HOME_USER now
  4637 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  4638 Isabelle installations.
  4639 
  4640 * isabelle-process: option -S (secure mode) disables some critical
  4641 operations, notably runtime compilation and evaluation of ML source
  4642 code.
  4643 
  4644 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  4645 
  4646 * Support for parallel execution, using native multicore support of
  4647 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  4648 independent theories, according to the given theory header
  4649 specifications. The maximum number of worker threads is specified via
  4650 usedir option -M or the "max-threads" setting in Proof General. A
  4651 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  4652 to 6 on a 8-core machine.  User-code needs to observe certain
  4653 guidelines for thread-safe programming, see appendix A in the Isar
  4654 Implementation manual.
  4655 
  4656 
  4657 
  4658 New in Isabelle2005 (October 2005)
  4659 ----------------------------------
  4660 
  4661 *** General ***
  4662 
  4663 * Theory headers: the new header syntax for Isar theories is
  4664 
  4665   theory <name>
  4666   imports <theory1> ... <theoryN>
  4667   uses <file1> ... <fileM>
  4668   begin
  4669 
  4670 where the 'uses' part is optional.  The previous syntax
  4671 
  4672   theory <name> = <theory1> + ... + <theoryN>:
  4673 
  4674 will disappear in the next release.  Use isatool fixheaders to convert
  4675 existing theory files.  Note that there is no change in ancient
  4676 non-Isar theories now, but these will disappear soon.
  4677 
  4678 * Theory loader: parent theories can now also be referred to via
  4679 relative and absolute paths.
  4680 
  4681 * Command 'find_theorems' searches for a list of criteria instead of a
  4682 list of constants. Known criteria are: intro, elim, dest, name:string,
  4683 simp:term, and any term. Criteria can be preceded by '-' to select
  4684 theorems that do not match. Intro, elim, dest select theorems that
  4685 match the current goal, name:s selects theorems whose fully qualified
  4686 name contain s, and simp:term selects all simplification rules whose
  4687 lhs match term.  Any other term is interpreted as pattern and selects
  4688 all theorems matching the pattern. Available in ProofGeneral under
  4689 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  4690 
  4691   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  4692 
  4693 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  4694 matching the current goal as introduction rule and not having "HOL."
  4695 in their name (i.e. not being defined in theory HOL).
  4696 
  4697 * Command 'thms_containing' has been discontinued in favour of
  4698 'find_theorems'; INCOMPATIBILITY.
  4699 
  4700 * Communication with Proof General is now 8bit clean, which means that
  4701 Unicode text in UTF-8 encoding may be used within theory texts (both
  4702 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4703 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4704 
  4705   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4706   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4707 
  4708 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4709 Classical Reasoner.  Typical big applications run around 2 times
  4710 faster.
  4711 
  4712 
  4713 *** Document preparation ***
  4714 
  4715 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4716 of raw sources.  Only those symbols that do not require additional
  4717 LaTeX packages (depending on comments in isabellesym.sty) are
  4718 displayed properly, everything else is left verbatim.  isatool display
  4719 and isatool print are used as front ends (these are subject to the
  4720 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4721 
  4722 * Command tags control specific markup of certain regions of text,
  4723 notably folding and hiding.  Predefined tags include "theory" (for
  4724 theory begin and end), "proof" for proof commands, and "ML" for
  4725 commands involving ML code; the additional tags "visible" and
  4726 "invisible" are unused by default.  Users may give explicit tag
  4727 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4728 interpretation of tags is determined by the LaTeX job during document
  4729 preparation: see option -V of isatool usedir, or options -n and -t of
  4730 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4731 \isadroptag.
  4732 
  4733 Several document versions may be produced at the same time via isatool
  4734 usedir (the generated index.html will link all of them).  Typical
  4735 specifications include ''-V document=theory,proof,ML'' to present
  4736 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4737 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4738 these parts without any formal replacement text.  The Isabelle site
  4739 default settings produce ''document'' and ''outline'' versions as
  4740 specified above.
  4741 
  4742 * Several new antiquotations:
  4743 
  4744   @{term_type term} prints a term with its type annotated;
  4745 
  4746   @{typeof term} prints the type of a term;
  4747 
  4748   @{const const} is the same as @{term const}, but checks that the
  4749   argument is a known logical constant;
  4750 
  4751   @{term_style style term} and @{thm_style style thm} print a term or
  4752   theorem applying a "style" to it
  4753 
  4754   @{ML text}
  4755 
  4756 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4757 definitions, equations, inequations etc., 'concl' printing only the
  4758 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4759 to print the specified premise.  TermStyle.add_style provides an ML
  4760 interface for introducing further styles.  See also the "LaTeX Sugar"
  4761 document practical applications.  The ML antiquotation prints
  4762 type-checked ML expressions verbatim.
  4763 
  4764 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4765 and 'text' support optional locale specification '(in loc)', which
  4766 specifies the default context for interpreting antiquotations.  For
  4767 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4768 
  4769 * Option 'locale=NAME' of antiquotations specifies an alternative
  4770 context interpreting the subsequent argument.  For example: @{thm
  4771 [locale=lattice] inf_assoc}.
  4772 
  4773 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4774 a proof context.
  4775 
  4776 * Proper output of antiquotations for theory commands involving a
  4777 proof context (such as 'locale' or 'theorem (in loc) ...').
  4778 
  4779 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4780 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4781 
  4782 * isatool usedir: new option -C (default true) controls whether option
  4783 -D should include a copy of the original document directory; -C false
  4784 prevents unwanted effects such as copying of administrative CVS data.
  4785 
  4786 
  4787 *** Pure ***
  4788 
  4789 * Considerably improved version of 'constdefs' command.  Now performs
  4790 automatic type-inference of declared constants; additional support for
  4791 local structure declarations (cf. locales and HOL records), see also
  4792 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4793 sequential dependencies of definitions within a single 'constdefs'
  4794 section; moreover, the declared name needs to be an identifier.  If
  4795 all fails, consider to fall back on 'consts' and 'defs' separately.
  4796 
  4797 * Improved indexed syntax and implicit structures.  First of all,
  4798 indexed syntax provides a notational device for subscripted
  4799 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4800 expressions.  Secondly, in a local context with structure
  4801 declarations, number indexes \<^sub>n or the empty index (default
  4802 number 1) refer to a certain fixed variable implicitly; option
  4803 show_structs controls printing of implicit structures.  Typical
  4804 applications of these concepts involve record types and locales.
  4805 
  4806 * New command 'no_syntax' removes grammar declarations (and
  4807 translations) resulting from the given syntax specification, which is
  4808 interpreted in the same manner as for the 'syntax' command.
  4809 
  4810 * 'Advanced' translation functions (parse_translation etc.) may depend
  4811 on the signature of the theory context being presently used for
  4812 parsing/printing, see also isar-ref manual.
  4813 
  4814 * Improved 'oracle' command provides a type-safe interface to turn an
  4815 ML expression of type theory -> T -> term into a primitive rule of
  4816 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4817 is already included here); see also FOL/ex/IffExample.thy;
  4818 INCOMPATIBILITY.
  4819 
  4820 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4821 before); "cI" is no longer bound, use "c.intro" instead.
  4822 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4823 axclasses vs. locales.
  4824 
  4825 * Improved internal renaming of symbolic identifiers -- attach primes
  4826 instead of base 26 numbers.
  4827 
  4828 * New flag show_question_marks controls printing of leading question
  4829 marks in schematic variable names.
  4830 
  4831 * In schematic variable names, *any* symbol following \<^isub> or
  4832 \<^isup> is now treated as part of the base name.  For example, the
  4833 following works without printing of awkward ".0" indexes:
  4834 
  4835   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4836     by simp
  4837 
  4838 * Inner syntax includes (*(*nested*) comments*).
  4839 
  4840 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4841 annotations as "(00...)".
  4842 
  4843 * Clear separation of logical types and nonterminals, where the latter
  4844 may only occur in 'syntax' specifications or type abbreviations.
  4845 Before that distinction was only partially implemented via type class
  4846 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4847 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4848 exotic syntax specifications may require further adaption
  4849 (e.g. Cube/Cube.thy).
  4850 
  4851 * Removed obsolete type class "logic", use the top sort {} instead.
  4852 Note that non-logical types should be declared as 'nonterminals'
  4853 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4854 specifications.
  4855 
  4856 * Attributes 'induct' and 'cases': type or set names may now be
  4857 locally fixed variables as well.
  4858 
  4859 * Simplifier: can now control the depth to which conditional rewriting
  4860 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4861 Limit.
  4862 
  4863 * Simplifier: simplification procedures may now take the current
  4864 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4865 interface), which is very useful for calling the Simplifier
  4866 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4867 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4868 low-level mk_simproc no longer applies Logic.varify internally, to
  4869 allow for use in a context of fixed variables.
  4870 
  4871 * thin_tac now works even if the assumption being deleted contains !!
  4872 or ==>.  More generally, erule now works even if the major premise of
  4873 the elimination rule contains !! or ==>.
  4874 
  4875 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4876 
  4877 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4878 from Pure, which contains all common declarations already.  Both
  4879 theories are defined via plain Isabelle/Isar .thy files.
  4880 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4881 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4882 use isatool fixcpure to adapt your theory and ML sources.
  4883 
  4884 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4885 selections of theorems in named facts via index ranges.
  4886 
  4887 * 'print_theorems': in theory mode, really print the difference
  4888 wrt. the last state (works for interactive theory development only),
  4889 in proof mode print all local facts (cf. 'print_facts');
  4890 
  4891 * 'hide': option '(open)' hides only base names.
  4892 
  4893 * More efficient treatment of intermediate checkpoints in interactive
  4894 theory development.
  4895 
  4896 * Code generator is now invoked via code_module (incremental code
  4897 generation) and code_library (modular code generation, ML structures
  4898 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4899 must be quoted when used as identifiers.
  4900 
  4901 * New 'value' command for reading, evaluating and printing terms using
  4902 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4903 quoted when used as identifier.
  4904 
  4905 
  4906 *** Locales ***
  4907 
  4908 * New commands for the interpretation of locale expressions in
  4909 theories (1), locales (2) and proof contexts (3).  These generate
  4910 proof obligations from the expression specification.  After the
  4911 obligations have been discharged, theorems of the expression are added
  4912 to the theory, target locale or proof context.  The synopsis of the
  4913 commands is a follows:
  4914 
  4915   (1) interpretation expr inst
  4916   (2) interpretation target < expr
  4917   (3) interpret expr inst
  4918 
  4919 Interpretation in theories and proof contexts require a parameter
  4920 instantiation of terms from the current context.  This is applied to
  4921 specifications and theorems of the interpreted expression.
  4922 Interpretation in locales only permits parameter renaming through the
  4923 locale expression.  Interpretation is smart in that interpretations
  4924 that are active already do not occur in proof obligations, neither are
  4925 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4926 inspect active interpretations of a particular locale.  For details,
  4927 see the Isar Reference manual.  Examples can be found in
  4928 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4929 
  4930 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4931 'interpret' instead.
  4932 
  4933 * New context element 'constrains' for adding type constraints to
  4934 parameters.
  4935 
  4936 * Context expressions: renaming of parameters with syntax
  4937 redeclaration.
  4938 
  4939 * Locale declaration: 'includes' disallowed.
  4940 
  4941 * Proper static binding of attribute syntax -- i.e. types / terms /
  4942 facts mentioned as arguments are always those of the locale definition
  4943 context, independently of the context of later invocations.  Moreover,
  4944 locale operations (renaming and type / term instantiation) are applied
  4945 to attribute arguments as expected.
  4946 
  4947 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4948 actual attributes; rare situations may require Attrib.attribute to
  4949 embed those attributes into Attrib.src that lack concrete syntax.
  4950 Attribute implementations need to cooperate properly with the static
  4951 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4952 Attrib.XXX_thm etc. already do the right thing without further
  4953 intervention.  Only unusual applications -- such as "where" or "of"
  4954 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4955 on the context and the facts involved -- may have to assign parsed
  4956 values to argument tokens explicitly.
  4957 
  4958 * Changed parameter management in theorem generation for long goal
  4959 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4960 theorem statement in rare situations.
  4961 
  4962 * Locale inspection command 'print_locale' omits notes elements.  Use
  4963 'print_locale!' to have them included in the output.
  4964 
  4965 
  4966 *** Provers ***
  4967 
  4968 * Provers/hypsubst.ML: improved version of the subst method, for
  4969 single-step rewriting: it now works in bound variable contexts. New is
  4970 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  4971 rewrite a different subterm than the original subst method, which is
  4972 still available as 'simplesubst'.
  4973 
  4974 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  4975 and quasi orders.
  4976 
  4977 * Provers/trancl.ML: new transitivity reasoner for transitive and
  4978 reflexive-transitive closure of relations.
  4979 
  4980 * Provers/blast.ML: new reference depth_limit to make blast's depth
  4981 limit (previously hard-coded with a value of 20) user-definable.
  4982 
  4983 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  4984 is peformed already.  Object-logics merely need to finish their
  4985 initial simpset configuration as before.  INCOMPATIBILITY.
  4986 
  4987 
  4988 *** HOL ***
  4989 
  4990 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  4991 
  4992   syntax (epsilon)
  4993     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  4994 
  4995 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  4996 and x-symbol; use option '-m epsilon' to get it actually printed.
  4997 Moreover, the mathematically important symbolic identifier \<epsilon>
  4998 becomes available as variable, constant etc.  INCOMPATIBILITY,
  4999 
  5000 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  5001 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  5002 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  5003 support corresponding Isar calculations.
  5004 
  5005 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  5006 instead of ":".
  5007 
  5008 * theory SetInterval: changed the syntax for open intervals:
  5009 
  5010   Old       New
  5011   {..n(}    {..<n}
  5012   {)n..}    {n<..}
  5013   {m..n(}   {m..<n}
  5014   {)m..n}   {m<..n}
  5015   {)m..n(}  {m<..<n}
  5016 
  5017 The old syntax is still supported but will disappear in the next
  5018 release.  For conversion use the following Emacs search and replace
  5019 patterns (these are not perfect but work quite well):
  5020 
  5021   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  5022   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  5023 
  5024 * Theory Commutative_Ring (in Library): method comm_ring for proving
  5025 equalities in commutative rings; method 'algebra' provides a generic
  5026 interface.
  5027 
  5028 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  5029 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  5030 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  5031 be a tuple pattern.
  5032 
  5033 Some new syntax forms are available:
  5034 
  5035   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  5036   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  5037   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  5038   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  5039 
  5040 The latter form "\<Sum>x < k. e" used to be based on a separate
  5041 function "Summation", which has been discontinued.
  5042 
  5043 * theory Finite_Set: in structured induction proofs, the insert case
  5044 is now 'case (insert x F)' instead of the old counterintuitive 'case
  5045 (insert F x)'.
  5046 
  5047 * The 'refute' command has been extended to support a much larger
  5048 fragment of HOL, including axiomatic type classes, constdefs and
  5049 typedefs, inductive datatypes and recursion.
  5050 
  5051 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  5052 Requires zChaff with proof generation to be installed.  See
  5053 HOL/ex/SAT_Examples.thy for examples.
  5054 
  5055 * Datatype induction via method 'induct' now preserves the name of the
  5056 induction variable. For example, when proving P(xs::'a list) by
  5057 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  5058 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  5059 in unstructured proof scripts.
  5060 
  5061 * Reworked implementation of records.  Improved scalability for
  5062 records with many fields, avoiding performance problems for type
  5063 inference. Records are no longer composed of nested field types, but
  5064 of nested extension types. Therefore the record type only grows linear
  5065 in the number of extensions and not in the number of fields.  The
  5066 top-level (users) view on records is preserved.  Potential
  5067 INCOMPATIBILITY only in strange cases, where the theory depends on the
  5068 old record representation. The type generated for a record is called
  5069 <record_name>_ext_type.
  5070 
  5071 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  5072 proofs triggered by a record definition or a simproc (if
  5073 quick_and_dirty is enabled).  Definitions of large records can take
  5074 quite long.
  5075 
  5076 New simproc record_upd_simproc for simplification of multiple record
  5077 updates enabled by default.  Moreover, trivial updates are also
  5078 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  5079 occasionally, since simplification is more powerful by default.
  5080 
  5081 * typedef: proper support for polymorphic sets, which contain extra
  5082 type-variables in the term.
  5083 
  5084 * Simplifier: automatically reasons about transitivity chains
  5085 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  5086 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  5087 old proofs break occasionally as simplification may now solve more
  5088 goals than previously.
  5089 
  5090 * Simplifier: converts x <= y into x = y if assumption y <= x is
  5091 present.  Works for all partial orders (class "order"), in particular
  5092 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  5093 just like y <= x.
  5094 
  5095 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  5096 bound variable or a constant then the let is unfolded.  Otherwise
  5097 first a is simplified to b, and then f b is simplified to g. If
  5098 possible we abstract b from g arriving at "let x = b in h x",
  5099 otherwise we unfold the let and arrive at g.  The simproc can be
  5100 enabled/disabled by the reference use_let_simproc.  Potential
  5101 INCOMPATIBILITY since simplification is more powerful by default.
  5102 
  5103 * Classical reasoning: the meson method now accepts theorems as arguments.
  5104 
  5105 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  5106 jobs to provide advice on the provability of subgoals.
  5107 
  5108 * Theory OrderedGroup and Ring_and_Field: various additions and
  5109 improvements to faciliate calculations involving equalities and
  5110 inequalities.
  5111 
  5112 The following theorems have been eliminated or modified
  5113 (INCOMPATIBILITY):
  5114 
  5115   abs_eq             now named abs_of_nonneg
  5116   abs_of_ge_0        now named abs_of_nonneg
  5117   abs_minus_eq       now named abs_of_nonpos
  5118   imp_abs_id         now named abs_of_nonneg
  5119   imp_abs_neg_id     now named abs_of_nonpos
  5120   mult_pos           now named mult_pos_pos
  5121   mult_pos_le        now named mult_nonneg_nonneg
  5122   mult_pos_neg_le    now named mult_nonneg_nonpos
  5123   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  5124   mult_neg           now named mult_neg_neg
  5125   mult_neg_le        now named mult_nonpos_nonpos
  5126 
  5127 * The following lemmas in Ring_and_Field have been added to the simplifier:
  5128      
  5129      zero_le_square
  5130      not_square_less_zero 
  5131 
  5132   The following lemmas have been deleted from Real/RealPow:
  5133   
  5134      realpow_zero_zero
  5135      realpow_two
  5136      realpow_less
  5137      zero_le_power
  5138      realpow_two_le
  5139      abs_realpow_two
  5140      realpow_two_abs     
  5141 
  5142 * Theory Parity: added rules for simplifying exponents.
  5143 
  5144 * Theory List:
  5145 
  5146 The following theorems have been eliminated or modified
  5147 (INCOMPATIBILITY):
  5148 
  5149   list_all_Nil       now named list_all.simps(1)
  5150   list_all_Cons      now named list_all.simps(2)
  5151   list_all_conv      now named list_all_iff
  5152   set_mem_eq         now named mem_iff
  5153 
  5154 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  5155 asymptotic "big O" calculations.  See the notes in BigO.thy.
  5156 
  5157 
  5158 *** HOL-Complex ***
  5159 
  5160 * Theory RealDef: better support for embedding natural numbers and
  5161 integers in the reals.
  5162 
  5163 The following theorems have been eliminated or modified
  5164 (INCOMPATIBILITY):
  5165 
  5166   exp_ge_add_one_self  now requires no hypotheses
  5167   real_of_int_add      reversed direction of equality (use [symmetric])
  5168   real_of_int_minus    reversed direction of equality (use [symmetric])
  5169   real_of_int_diff     reversed direction of equality (use [symmetric])
  5170   real_of_int_mult     reversed direction of equality (use [symmetric])
  5171 
  5172 * Theory RComplete: expanded support for floor and ceiling functions.
  5173 
  5174 * Theory Ln is new, with properties of the natural logarithm
  5175 
  5176 * Hyperreal: There is a new type constructor "star" for making
  5177 nonstandard types.  The old type names are now type synonyms:
  5178 
  5179   hypreal = real star
  5180   hypnat = nat star
  5181   hcomplex = complex star
  5182 
  5183 * Hyperreal: Many groups of similarly-defined constants have been
  5184 replaced by polymorphic versions (INCOMPATIBILITY):
  5185 
  5186   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  5187 
  5188   starset      <-- starsetNat, starsetC
  5189   *s*          <-- *sNat*, *sc*
  5190   starset_n    <-- starsetNat_n, starsetC_n
  5191   *sn*         <-- *sNatn*, *scn*
  5192   InternalSets <-- InternalNatSets, InternalCSets
  5193 
  5194   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  5195   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  5196   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  5197   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  5198   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  5199 
  5200 * Hyperreal: Many type-specific theorems have been removed in favor of
  5201 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  5202 
  5203   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  5204   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  5205   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  5206   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  5207   right_minus <-- hypreal_add_minus
  5208   left_minus <-- {hypreal,hcomplex}_add_minus_left
  5209   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  5210   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  5211   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  5212   mult_1_right <-- hcomplex_mult_one_right
  5213   mult_zero_left <-- hcomplex_mult_zero_left
  5214   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  5215   right_distrib <-- hypnat_add_mult_distrib2
  5216   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  5217   right_inverse <-- hypreal_mult_inverse
  5218   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  5219   order_refl <-- {hypreal,hypnat}_le_refl
  5220   order_trans <-- {hypreal,hypnat}_le_trans
  5221   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  5222   order_less_le <-- {hypreal,hypnat}_less_le
  5223   linorder_linear <-- {hypreal,hypnat}_le_linear
  5224   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  5225   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  5226   add_nonneg_nonneg <-- hypreal_le_add_order
  5227 
  5228 * Hyperreal: Separate theorems having to do with type-specific
  5229 versions of constants have been merged into theorems that apply to the
  5230 new polymorphic constants (INCOMPATIBILITY):
  5231 
  5232   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  5233   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  5234   STAR_Un <-- {STAR,NatStar,STARC}_Un
  5235   STAR_Int <-- {STAR,NatStar,STARC}_Int
  5236   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  5237   STAR_subset <-- {STAR,NatStar,STARC}_subset
  5238   STAR_mem <-- {STAR,NatStar,STARC}_mem
  5239   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  5240   STAR_diff <-- {STAR,STARC}_diff
  5241   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  5242     STARC_hcomplex_of_complex}_image_subset
  5243   starset_n_Un <-- starset{Nat,C}_n_Un
  5244   starset_n_Int <-- starset{Nat,C}_n_Int
  5245   starset_n_Compl <-- starset{Nat,C}_n_Compl
  5246   starset_n_diff <-- starset{Nat,C}_n_diff
  5247   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  5248   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  5249   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  5250   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  5251   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  5252   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  5253   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  5254   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  5255   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  5256   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  5257   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  5258   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  5259   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  5260   starfun_diff <-- starfun{C,RC,CR}_diff
  5261   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  5262   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  5263   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  5264   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  5265   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  5266   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  5267   starfun_Id <-- starfunC_Id
  5268   starfun_approx <-- starfun{Nat,CR}_approx
  5269   starfun_capprox <-- starfun{C,RC}_capprox
  5270   starfun_abs <-- starfunNat_rabs
  5271   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  5272   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  5273   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  5274   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  5275   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  5276   starfun_add_approx <-- starfunCR_add_approx
  5277   starfun_inverse_inverse <-- starfunC_inverse_inverse
  5278   starfun_divide <-- starfun{C,CR,RC}_divide
  5279   starfun_n <-- starfun{Nat,C}_n
  5280   starfun_n_mult <-- starfun{Nat,C}_n_mult
  5281   starfun_n_add <-- starfun{Nat,C}_n_add
  5282   starfun_n_add_minus <-- starfunNat_n_add_minus
  5283   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  5284   starfun_n_minus <-- starfun{Nat,C}_n_minus
  5285   starfun_n_eq <-- starfun{Nat,C}_n_eq
  5286 
  5287   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  5288   star_n_minus <-- {hypreal,hcomplex}_minus
  5289   star_n_diff <-- {hypreal,hcomplex}_diff
  5290   star_n_mult <-- {hypreal,hcomplex}_mult
  5291   star_n_inverse <-- {hypreal,hcomplex}_inverse
  5292   star_n_le <-- {hypreal,hypnat}_le
  5293   star_n_less <-- {hypreal,hypnat}_less
  5294   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  5295   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  5296   star_n_abs <-- hypreal_hrabs
  5297   star_n_divide <-- hcomplex_divide
  5298 
  5299   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  5300   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  5301   star_of_diff <-- hypreal_of_real_diff
  5302   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  5303   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  5304   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  5305   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  5306   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  5307   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  5308   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  5309   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  5310   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  5311   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  5312   star_of_number_of <-- {hypreal,hcomplex}_number_of
  5313   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  5314   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  5315   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  5316   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  5317   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  5318   star_of_power <-- hypreal_of_real_power
  5319   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  5320 
  5321 * Hyperreal: new method "transfer" that implements the transfer
  5322 principle of nonstandard analysis. With a subgoal that mentions
  5323 nonstandard types like "'a star", the command "apply transfer"
  5324 replaces it with an equivalent one that mentions only standard types.
  5325 To be successful, all free variables must have standard types; non-
  5326 standard variables must have explicit universal quantifiers.
  5327 
  5328 * Hyperreal: A theory of Taylor series.
  5329 
  5330 
  5331 *** HOLCF ***
  5332 
  5333 * Discontinued special version of 'constdefs' (which used to support
  5334 continuous functions) in favor of the general Pure one with full
  5335 type-inference.
  5336 
  5337 * New simplification procedure for solving continuity conditions; it
  5338 is much faster on terms with many nested lambda abstractions (cubic
  5339 instead of exponential time).
  5340 
  5341 * New syntax for domain package: selector names are now optional.
  5342 Parentheses should be omitted unless argument is lazy, for example:
  5343 
  5344   domain 'a stream = cons "'a" (lazy "'a stream")
  5345 
  5346 * New command 'fixrec' for defining recursive functions with pattern
  5347 matching; defining multiple functions with mutual recursion is also
  5348 supported.  Patterns may include the constants cpair, spair, up, sinl,
  5349 sinr, or any data constructor defined by the domain package. The given
  5350 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  5351 syntax and examples.
  5352 
  5353 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  5354 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  5355 but the proof obligation additionally includes an admissibility
  5356 requirement. The packages generate instances of class cpo or pcpo,
  5357 with continuity and strictness theorems for Rep and Abs.
  5358 
  5359 * HOLCF: Many theorems have been renamed according to a more standard naming
  5360 scheme (INCOMPATIBILITY):
  5361 
  5362   foo_inject:  "foo$x = foo$y ==> x = y"
  5363   foo_eq:      "(foo$x = foo$y) = (x = y)"
  5364   foo_less:    "(foo$x << foo$y) = (x << y)"
  5365   foo_strict:  "foo$UU = UU"
  5366   foo_defined: "... ==> foo$x ~= UU"
  5367   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  5368 
  5369 
  5370 *** ZF ***
  5371 
  5372 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  5373 including the First Isomorphism Theorem (on quotienting by the kernel
  5374 of a homomorphism).
  5375 
  5376 * ZF/Simplifier: install second copy of type solver that actually
  5377 makes use of TC rules declared to Isar proof contexts (or locales);
  5378 the old version is still required for ML proof scripts.
  5379 
  5380 
  5381 *** Cube ***
  5382 
  5383 * Converted to Isar theory format; use locales instead of axiomatic
  5384 theories.
  5385 
  5386 
  5387 *** ML ***
  5388 
  5389 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  5390 for ||>, ||>>, |>>,
  5391 
  5392 * Pure/library.ML no longer defines its own option datatype, but uses
  5393 that of the SML basis, which has constructors NONE and SOME instead of
  5394 None and Some, as well as exception Option.Option instead of OPTION.
  5395 The functions the, if_none, is_some, is_none have been adapted
  5396 accordingly, while Option.map replaces apsome.
  5397 
  5398 * Pure/library.ML: the exception LIST has been given up in favour of
  5399 the standard exceptions Empty and Subscript, as well as
  5400 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  5401 superceded by the standard hd and tl functions etc.
  5402 
  5403 A number of basic list functions are no longer exported to the ML
  5404 toplevel, as they are variants of predefined functions.  The following
  5405 suggests how one can translate existing code:
  5406 
  5407     rev_append xs ys = List.revAppend (xs, ys)
  5408     nth_elem (i, xs) = List.nth (xs, i)
  5409     last_elem xs = List.last xs
  5410     flat xss = List.concat xss
  5411     seq fs = List.app fs
  5412     partition P xs = List.partition P xs
  5413     mapfilter f xs = List.mapPartial f xs
  5414 
  5415 * Pure/library.ML: several combinators for linear functional
  5416 transformations, notably reverse application and composition:
  5417 
  5418   x |> f                f #> g
  5419   (x, y) |-> f          f #-> g
  5420 
  5421 * Pure/library.ML: introduced/changed precedence of infix operators:
  5422 
  5423   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  5424   infix 2 ?;
  5425   infix 3 o oo ooo oooo;
  5426   infix 4 ~~ upto downto;
  5427 
  5428 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  5429 infix operators.
  5430 
  5431 * Pure/library.ML: natural list combinators fold, fold_rev, and
  5432 fold_map support linear functional transformations and nesting.  For
  5433 example:
  5434 
  5435   fold f [x1, ..., xN] y =
  5436     y |> f x1 |> ... |> f xN
  5437 
  5438   (fold o fold) f [xs1, ..., xsN] y =
  5439     y |> fold f xs1 |> ... |> fold f xsN
  5440 
  5441   fold f [x1, ..., xN] =
  5442     f x1 #> ... #> f xN
  5443 
  5444   (fold o fold) f [xs1, ..., xsN] =
  5445     fold f xs1 #> ... #> fold f xsN
  5446 
  5447 * Pure/library.ML: the following selectors on type 'a option are
  5448 available:
  5449 
  5450   the:               'a option -> 'a  (*partial*)
  5451   these:             'a option -> 'a  where 'a = 'b list
  5452   the_default: 'a -> 'a option -> 'a
  5453   the_list:          'a option -> 'a list
  5454 
  5455 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5456 basic operations for association lists, following natural argument
  5457 order; moreover the explicit equality predicate passed here avoids
  5458 potentially expensive polymorphic runtime equality checks.
  5459 The old functions may be expressed as follows:
  5460 
  5461   assoc = uncurry (AList.lookup (op =))
  5462   assocs = these oo AList.lookup (op =)
  5463   overwrite = uncurry (AList.update (op =)) o swap
  5464 
  5465 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5466 
  5467   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  5468   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  5469 
  5470 replacing make_keylist and keyfilter (occassionally used)
  5471 Naive rewrites:
  5472 
  5473   make_keylist = AList.make
  5474   keyfilter = AList.find (op =)
  5475 
  5476 * eq_fst and eq_snd now take explicit equality parameter, thus
  5477   avoiding eqtypes. Naive rewrites:
  5478 
  5479     eq_fst = eq_fst (op =)
  5480     eq_snd = eq_snd (op =)
  5481 
  5482 * Removed deprecated apl and apr (rarely used).
  5483   Naive rewrites:
  5484 
  5485     apl (n, op) =>>= curry op n
  5486     apr (op, m) =>>= fn n => op (n, m)
  5487 
  5488 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  5489 provides a reasonably efficient light-weight implementation of sets as
  5490 lists.
  5491 
  5492 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  5493 few new operations; existing lookup and update are now curried to
  5494 follow natural argument order (for use with fold etc.);
  5495 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  5496 
  5497 * Pure/General: output via the Isabelle channels of
  5498 writeln/warning/error etc. is now passed through Output.output, with a
  5499 hook for arbitrary transformations depending on the print_mode
  5500 (cf. Output.add_mode -- the first active mode that provides a output
  5501 function wins).  Already formatted output may be embedded into further
  5502 text via Output.raw; the result of Pretty.string_of/str_of and derived
  5503 functions (string_of_term/cterm/thm etc.) is already marked raw to
  5504 accommodate easy composition of diagnostic messages etc.  Programmers
  5505 rarely need to care about Output.output or Output.raw at all, with
  5506 some notable exceptions: Output.output is required when bypassing the
  5507 standard channels (writeln etc.), or in token translations to produce
  5508 properly formatted results; Output.raw is required when capturing
  5509 already output material that will eventually be presented to the user
  5510 a second time.  For the default print mode, both Output.output and
  5511 Output.raw have no effect.
  5512 
  5513 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  5514 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  5515 cumulative results are displayed at the end of a batch session.
  5516 
  5517 * Pure/General: File.sysify_path and File.quote_sysify path have been
  5518 replaced by File.platform_path and File.shell_path (with appropriate
  5519 hooks).  This provides a clean interface for unusual systems where the
  5520 internal and external process view of file names are different.
  5521 
  5522 * Pure: more efficient orders for basic syntactic entities: added
  5523 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  5524 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  5525 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  5526 orders now -- potential INCOMPATIBILITY for code that depends on a
  5527 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  5528 Library.sort_strings on result).
  5529 
  5530 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  5531 fold_types traverse types/terms from left to right, observing natural
  5532 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  5533 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  5534 
  5535 * Pure: name spaces have been refined, with significant changes of the
  5536 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  5537 to extern(_table).  The plain name entry path is superceded by a
  5538 general 'naming' context, which also includes the 'policy' to produce
  5539 a fully qualified name and external accesses of a fully qualified
  5540 name; NameSpace.extend is superceded by context dependent
  5541 Sign.declare_name.  Several theory and proof context operations modify
  5542 the naming context.  Especially note Theory.restore_naming and
  5543 ProofContext.restore_naming to get back to a sane state; note that
  5544 Theory.add_path is no longer sufficient to recover from
  5545 Theory.absolute_path in particular.
  5546 
  5547 * Pure: new flags short_names (default false) and unique_names
  5548 (default true) for controlling output of qualified names.  If
  5549 short_names is set, names are printed unqualified.  If unique_names is
  5550 reset, the name prefix is reduced to the minimum required to achieve
  5551 the original result when interning again, even if there is an overlap
  5552 with earlier declarations.
  5553 
  5554 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  5555 now 'extend', and 'merge' gets an additional Pretty.pp argument
  5556 (useful for printing error messages).  INCOMPATIBILITY.
  5557 
  5558 * Pure: major reorganization of the theory context.  Type Sign.sg and
  5559 Theory.theory are now identified, referring to the universal
  5560 Context.theory (see Pure/context.ML).  Actual signature and theory
  5561 content is managed as theory data.  The old code and interfaces were
  5562 spread over many files and structures; the new arrangement introduces
  5563 considerable INCOMPATIBILITY to gain more clarity:
  5564 
  5565   Context -- theory management operations (name, identity, inclusion,
  5566     parents, ancestors, merge, etc.), plus generic theory data;
  5567 
  5568   Sign -- logical signature and syntax operations (declaring consts,
  5569     types, etc.), plus certify/read for common entities;
  5570 
  5571   Theory -- logical theory operations (stating axioms, definitions,
  5572     oracles), plus a copy of logical signature operations (consts,
  5573     types, etc.); also a few basic management operations (Theory.copy,
  5574     Theory.merge, etc.)
  5575 
  5576 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  5577 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  5578 for convenience -- they merely return the theory.
  5579 
  5580 * Pure: type Type.tsig is superceded by theory in most interfaces.
  5581 
  5582 * Pure: the Isar proof context type is already defined early in Pure
  5583 as Context.proof (note that ProofContext.context and Proof.context are
  5584 aliases, where the latter is the preferred name).  This enables other
  5585 Isabelle components to refer to that type even before Isar is present.
  5586 
  5587 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  5588 typeK, constK, axiomK, oracleK), but provide explicit operations for
  5589 any of these kinds.  For example, Sign.intern typeK is now
  5590 Sign.intern_type, Theory.hide_space Sign.typeK is now
  5591 Theory.hide_types.  Also note that former
  5592 Theory.hide_classes/types/consts are now
  5593 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  5594 internalize their arguments!  INCOMPATIBILITY.
  5595 
  5596 * Pure: get_thm interface (of PureThy and ProofContext) expects
  5597 datatype thmref (with constructors Name and NameSelection) instead of
  5598 plain string -- INCOMPATIBILITY;
  5599 
  5600 * Pure: cases produced by proof methods specify options, where NONE
  5601 means to remove case bindings -- INCOMPATIBILITY in
  5602 (RAW_)METHOD_CASES.
  5603 
  5604 * Pure: the following operations retrieve axioms or theorems from a
  5605 theory node or theory hierarchy, respectively:
  5606 
  5607   Theory.axioms_of: theory -> (string * term) list
  5608   Theory.all_axioms_of: theory -> (string * term) list
  5609   PureThy.thms_of: theory -> (string * thm) list
  5610   PureThy.all_thms_of: theory -> (string * thm) list
  5611 
  5612 * Pure: print_tac now outputs the goal through the trace channel.
  5613 
  5614 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  5615 Reference Toplevel.debug (default false) controls detailed printing
  5616 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  5617 controls execution profiling -- set to 1 for time and 2 for space
  5618 (both increase the runtime).
  5619 
  5620 * Isar session: The initial use of ROOT.ML is now always timed,
  5621 i.e. the log will show the actual process times, in contrast to the
  5622 elapsed wall-clock time that the outer shell wrapper produces.
  5623 
  5624 * Simplifier: improved handling of bound variables (nameless
  5625 representation, avoid allocating new strings).  Simprocs that invoke
  5626 the Simplifier recursively should use Simplifier.inherit_bounds to
  5627 avoid local name clashes.  Failure to do so produces warnings
  5628 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  5629 for further details.
  5630 
  5631 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  5632 bindings for all theorems stored within a given theory; this may help
  5633 in porting non-Isar theories to Isar ones, while keeping ML proof
  5634 scripts for the time being.
  5635 
  5636 * ML operator HTML.with_charset specifies the charset begin used for
  5637 generated HTML files.  For example:
  5638 
  5639   HTML.with_charset "utf-8" use_thy "Hebrew";
  5640   HTML.with_charset "utf-8" use_thy "Chinese";
  5641 
  5642 
  5643 *** System ***
  5644 
  5645 * Allow symlinks to all proper Isabelle executables (Isabelle,
  5646 isabelle, isatool etc.).
  5647 
  5648 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  5649 isatool doc, isatool mkdir, display_drafts etc.).
  5650 
  5651 * isatool usedir: option -f allows specification of the ML file to be
  5652 used by Isabelle; default is ROOT.ML.
  5653 
  5654 * New isatool version outputs the version identifier of the Isabelle
  5655 distribution being used.
  5656 
  5657 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  5658 (containing Boolean satisfiability problems) into Isabelle/HOL
  5659 theories.
  5660 
  5661 
  5662 
  5663 New in Isabelle2004 (April 2004)
  5664 --------------------------------
  5665 
  5666 *** General ***
  5667 
  5668 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  5669   Replaces linorder.ML.
  5670 
  5671 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  5672   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  5673   (\<a>...\<z>), are now considered normal letters, and can therefore
  5674   be used anywhere where an ASCII letter (a...zA...Z) has until
  5675   now. COMPATIBILITY: This obviously changes the parsing of some
  5676   terms, especially where a symbol has been used as a binder, say
  5677   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  5678   as an identifier.  Fix it by inserting a space around former
  5679   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  5680   existing theory and ML files.
  5681 
  5682 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  5683 
  5684 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  5685   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  5686   a normal (but invisible) letter. For multiple letter subscripts repeat
  5687   \<^isub> like this: x\<^isub>1\<^isub>2.
  5688 
  5689 * Pure: There are now sub-/superscripts that can span more than one
  5690   character. Text between \<^bsub> and \<^esub> is set in subscript in
  5691   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  5692   superscript. The new control characters are not identifier parts.
  5693 
  5694 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5695   content of "..." to the latex file instead of \isacntrl... . The "..."
  5696   may consist of any printable characters excluding the end bracket >.
  5697 
  5698 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5699   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5700   declare constants "final", which prevents their being given a definition
  5701   later.  It is useful for constants whose behaviour is fixed axiomatically
  5702   rather than definitionally, such as the meta-logic connectives.
  5703 
  5704 * Pure: 'instance' now handles general arities with general sorts
  5705   (i.e. intersections of classes),
  5706 
  5707 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5708   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5709   It can be changed to alter the colors/layout of generated pages.
  5710 
  5711 
  5712 *** Isar ***
  5713 
  5714 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5715   cut_tac, subgoal_tac and thin_tac:
  5716   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5717     locales are no longer forced to write Isar proof scripts.
  5718     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5719     emulations.
  5720   - INCOMPATIBILITY: names of variables to be instantiated may no
  5721     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5722     This is consistent with the instantiation attribute "where".
  5723 
  5724 * Attributes "where" and "of":
  5725   - Now take type variables of instantiated theorem into account when reading
  5726     the instantiation string.  This fixes a bug that caused instantiated
  5727     theorems to have too special types in some circumstances.
  5728   - "where" permits explicit instantiations of type variables.
  5729 
  5730 * Calculation commands "moreover" and "also" no longer interfere with
  5731   current facts ("this"), admitting arbitrary combinations with "then"
  5732   and derived forms.
  5733 
  5734 * Locales:
  5735   - Goal statements involving the context element "includes" no longer
  5736     generate theorems with internal delta predicates (those ending on
  5737     "_axioms") in the premise.
  5738     Resolve particular premise with <locale>.intro to obtain old form.
  5739   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5740     specification and "includes" elements in goal statement.
  5741   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5742     [intro?] and [elim?] (respectively) by default.
  5743   - Experimental command for instantiation of locales in proof contexts:
  5744         instantiate <label>[<attrs>]: <loc>
  5745     Instantiates locale <loc> and adds all its theorems to the current context
  5746     taking into account their attributes.  Label and attrs are optional
  5747     modifiers, like in theorem declarations.  If present, names of
  5748     instantiated theorems are qualified with <label>, and the attributes
  5749     <attrs> are applied after any attributes these theorems might have already.
  5750       If the locale has assumptions, a chained fact of the form
  5751     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5752     are derived.  The command does not support old-style locales declared
  5753     with "locale (open)".
  5754       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5755 
  5756 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5757   (Isar) contexts.
  5758 
  5759 
  5760 *** HOL ***
  5761 
  5762 * Proof import: new image HOL4 contains the imported library from
  5763   the HOL4 system with about 2500 theorems. It is imported by
  5764   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5765   can be used like any other Isabelle image.  See
  5766   HOL/Import/HOL/README for more information.
  5767 
  5768 * Simplifier:
  5769   - Much improved handling of linear and partial orders.
  5770     Reasoners for linear and partial orders are set up for type classes
  5771     "linorder" and "order" respectively, and are added to the default simpset
  5772     as solvers.  This means that the simplifier can build transitivity chains
  5773     to solve goals from the assumptions.
  5774   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5775     of blast or auto after simplification become unnecessary because the goal
  5776     is solved by simplification already.
  5777 
  5778 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5779     all proved in axiomatic type classes for semirings, rings and fields.
  5780 
  5781 * Numerics:
  5782   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5783     now formalized using the Ring_and_Field theory mentioned above.
  5784   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5785     than before, because now they are set up once in a generic manner.
  5786   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5787     Look for the general versions in Ring_and_Field (and Power if they concern
  5788     exponentiation).
  5789 
  5790 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5791 
  5792 * Records:
  5793   - Record types are now by default printed with their type abbreviation
  5794     instead of the list of all field types. This can be configured via
  5795     the reference "print_record_type_abbr".
  5796   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5797     (not enabled by default).
  5798   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5799     EX x. x = sel r to True (not enabled by default).
  5800   - Tactic "record_split_simp_tac" to split and simplify records added.
  5801 
  5802 * 'specification' command added, allowing for definition by
  5803   specification.  There is also an 'ax_specification' command that
  5804   introduces the new constants axiomatically.
  5805 
  5806 * arith(_tac) is now able to generate counterexamples for reals as well.
  5807 
  5808 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5809 
  5810 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5811   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5812 
  5813 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5814   matrix theory to linear programming.
  5815 
  5816 * Unions and Intersections:
  5817   The latex output syntax of UN and INT has been changed
  5818   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5819   i.e. the index formulae has become a subscript.
  5820   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5821 
  5822 * Unions and Intersections over Intervals:
  5823   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5824   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5825   like in normal math, and corresponding versions for < and for intersection.
  5826 
  5827 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5828   lexicographic dictonary ordering has been added as "lexord".
  5829 
  5830 * ML: the legacy theory structures Int and List have been removed. They had
  5831   conflicted with ML Basis Library structures having the same names.
  5832 
  5833 * 'refute' command added to search for (finite) countermodels.  Only works
  5834   for a fragment of HOL.  The installation of an external SAT solver is
  5835   highly recommended.  See "HOL/Refute.thy" for details.
  5836 
  5837 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5838   formulae under an assignment of free variables to random values.
  5839   In contrast to 'refute', it can deal with inductive datatypes,
  5840   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5841   for examples.
  5842 
  5843 
  5844 *** HOLCF ***
  5845 
  5846 * Streams now come with concatenation and are part of the HOLCF image
  5847 
  5848 
  5849 
  5850 New in Isabelle2003 (May 2003)
  5851 ------------------------------
  5852 
  5853 *** General ***
  5854 
  5855 * Provers/simplifier:
  5856 
  5857   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5858     Assumptions are now subject to complete mutual simplification,
  5859     not just from left to right. The simplifier now preserves
  5860     the order of assumptions.
  5861 
  5862     Potential INCOMPATIBILITY:
  5863 
  5864     -- simp sometimes diverges where the old version did
  5865        not, e.g. invoking simp on the goal
  5866 
  5867         [| P (f x); y = x; f x = f y |] ==> Q
  5868 
  5869        now gives rise to the infinite reduction sequence
  5870 
  5871         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5872 
  5873        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5874        kind of problem.
  5875 
  5876     -- Tactics combining classical reasoner and simplification (such as auto)
  5877        are also affected by this change, because many of them rely on
  5878        simp. They may sometimes diverge as well or yield a different numbers
  5879        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5880        in case of problems. Sometimes subsequent calls to the classical
  5881        reasoner will fail because a preceeding call to the simplifier too
  5882        eagerly simplified the goal, e.g. deleted redundant premises.
  5883 
  5884   - The simplifier trace now shows the names of the applied rewrite rules
  5885 
  5886   - You can limit the number of recursive invocations of the simplifier
  5887     during conditional rewriting (where the simplifie tries to solve the
  5888     conditions before applying the rewrite rule):
  5889     ML "simp_depth_limit := n"
  5890     where n is an integer. Thus you can force termination where previously
  5891     the simplifier would diverge.
  5892 
  5893   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5894 
  5895   - No longer aborts on failed congruence proof.  Instead, the
  5896     congruence is ignored.
  5897 
  5898 * Pure: New generic framework for extracting programs from constructive
  5899   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5900   as HOL/Extraction for some case studies.
  5901 
  5902 * Pure: The main goal of the proof state is no longer shown by default, only
  5903 the subgoals. This behaviour is controlled by a new flag.
  5904    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5905 (ML: Proof.show_main_goal).
  5906 
  5907 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5908 rules whose conclusion matches subgoal 1:
  5909       PG menu: Isabelle/Isar -> Show me -> matching rules
  5910 The rules are ordered by how closely they match the subgoal.
  5911 In particular, rules that solve a subgoal outright are displayed first
  5912 (or rather last, the way they are printed).
  5913 (ML: ProofGeneral.print_intros())
  5914 
  5915 * Pure: New flag trace_unify_fail causes unification to print
  5916 diagnostic information (PG: in trace buffer) when it fails. This is
  5917 useful for figuring out why single step proofs like rule, erule or
  5918 assumption failed.
  5919 
  5920 * Pure: Locale specifications now produce predicate definitions
  5921 according to the body of text (covering assumptions modulo local
  5922 definitions); predicate "loc_axioms" covers newly introduced text,
  5923 while "loc" is cumulative wrt. all included locale expressions; the
  5924 latter view is presented only on export into the global theory
  5925 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5926 on the old view without predicates;
  5927 
  5928 * Pure: predefined locales "var" and "struct" are useful for sharing
  5929 parameters (as in CASL, for example); just specify something like
  5930 ``var x + var y + struct M'' as import;
  5931 
  5932 * Pure: improved thms_containing: proper indexing of facts instead of
  5933 raw theorems; check validity of results wrt. current name space;
  5934 include local facts of proof configuration (also covers active
  5935 locales), cover fixed variables in index; may use "_" in term
  5936 specification; an optional limit for the number of printed facts may
  5937 be given (the default is 40);
  5938 
  5939 * Pure: disallow duplicate fact bindings within new-style theory files
  5940 (batch-mode only);
  5941 
  5942 * Provers: improved induct method: assumptions introduced by case
  5943 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5944 the goal statement); "foo" still refers to all facts collectively;
  5945 
  5946 * Provers: the function blast.overloaded has been removed: all constants
  5947 are regarded as potentially overloaded, which improves robustness in exchange
  5948 for slight decrease in efficiency;
  5949 
  5950 * Provers/linorder: New generic prover for transitivity reasoning over
  5951 linear orders.  Note: this prover is not efficient!
  5952 
  5953 * Isar: preview of problems to finish 'show' now produce an error
  5954 rather than just a warning (in interactive mode);
  5955 
  5956 
  5957 *** HOL ***
  5958 
  5959 * arith(_tac)
  5960 
  5961  - Produces a counter example if it cannot prove a goal.
  5962    Note that the counter example may be spurious if the goal is not a formula
  5963    of quantifier-free linear arithmetic.
  5964    In ProofGeneral the counter example appears in the trace buffer.
  5965 
  5966  - Knows about div k and mod k where k is a numeral of type nat or int.
  5967 
  5968  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  5969    linear arithmetic fails. This takes account of quantifiers and divisibility.
  5970    Presburger arithmetic can also be called explicitly via presburger(_tac).
  5971 
  5972 * simp's arithmetic capabilities have been enhanced a bit: it now
  5973 takes ~= in premises into account (by performing a case split);
  5974 
  5975 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  5976 are distributed over a sum of terms;
  5977 
  5978 * New tactic "trans_tac" and method "trans" instantiate
  5979 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  5980 "<=", "<" and "=").
  5981 
  5982 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  5983 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  5984 
  5985 * 'typedef' command has new option "open" to suppress the set
  5986 definition;
  5987 
  5988 * functions Min and Max on finite sets have been introduced (theory
  5989 Finite_Set);
  5990 
  5991 * attribute [symmetric] now works for relations as well; it turns
  5992 (x,y) : R^-1 into (y,x) : R, and vice versa;
  5993 
  5994 * induct over a !!-quantified statement (say !!x1..xn):
  5995   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  5996 
  5997 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  5998 %x. None. Warning: empty_def now refers to the previously hidden definition
  5999 of the empty set.
  6000 
  6001 * Algebra: formalization of classical algebra.  Intended as base for
  6002 any algebraic development in Isabelle.  Currently covers group theory
  6003 (up to Sylow's theorem) and ring theory (Universal Property of
  6004 Univariate Polynomials).  Contributions welcome;
  6005 
  6006 * GroupTheory: deleted, since its material has been moved to Algebra;
  6007 
  6008 * Complex: new directory of the complex numbers with numeric constants,
  6009 nonstandard complex numbers, and some complex analysis, standard and
  6010 nonstandard (Jacques Fleuriot);
  6011 
  6012 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  6013 
  6014 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  6015 Fleuriot);
  6016 
  6017 * Real/HahnBanach: updated and adapted to locales;
  6018 
  6019 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  6020 Gray and Kramer);
  6021 
  6022 * UNITY: added the Meier-Sanders theory of progress sets;
  6023 
  6024 * MicroJava: bytecode verifier and lightweight bytecode verifier
  6025 as abstract algorithms, instantiated to the JVM;
  6026 
  6027 * Bali: Java source language formalization. Type system, operational
  6028 semantics, axiomatic semantics. Supported language features:
  6029 classes, interfaces, objects,virtual methods, static methods,
  6030 static/instance fields, arrays, access modifiers, definite
  6031 assignment, exceptions.
  6032 
  6033 
  6034 *** ZF ***
  6035 
  6036 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  6037 universe, etc.);
  6038 
  6039 * Main ZF: virtually all theories converted to new-style format;
  6040 
  6041 
  6042 *** ML ***
  6043 
  6044 * Pure: Tactic.prove provides sane interface for internal proofs;
  6045 omits the infamous "standard" operation, so this is more appropriate
  6046 than prove_goalw_cterm in many situations (e.g. in simprocs);
  6047 
  6048 * Pure: improved error reporting of simprocs;
  6049 
  6050 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  6051 up simprocs;
  6052 
  6053 
  6054 *** Document preparation ***
  6055 
  6056 * uses \par instead of \\ for line breaks in theory text. This may
  6057 shift some page breaks in large documents. To get the old behaviour
  6058 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  6059 
  6060 * minimized dependencies of isabelle.sty and isabellesym.sty on
  6061 other packages
  6062 
  6063 * \<euro> now needs package babel/greek instead of marvosym (which
  6064 broke \Rightarrow)
  6065 
  6066 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  6067 textcomp package)
  6068 
  6069 
  6070 
  6071 New in Isabelle2002 (March 2002)
  6072 --------------------------------
  6073 
  6074 *** Document preparation ***
  6075 
  6076 * greatly simplified document preparation setup, including more
  6077 graceful interpretation of isatool usedir -i/-d/-D options, and more
  6078 instructive isatool mkdir; users should basically be able to get
  6079 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  6080 users may run a separate document processing stage manually like this:
  6081 "isatool usedir -D output HOL Test && isatool document Test/output";
  6082 
  6083 * theory dependency graph may now be incorporated into documents;
  6084 isatool usedir -g true will produce session_graph.eps/.pdf for use
  6085 with \includegraphics of LaTeX;
  6086 
  6087 * proper spacing of consecutive markup elements, especially text
  6088 blocks after section headings;
  6089 
  6090 * support bold style (for single symbols only), input syntax is like
  6091 this: "\<^bold>\<alpha>" or "\<^bold>A";
  6092 
  6093 * \<bullet> is now output as bold \cdot by default, which looks much
  6094 better in printed text;
  6095 
  6096 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  6097 note that these symbols are currently unavailable in Proof General /
  6098 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  6099 
  6100 * isatool latex no longer depends on changed TEXINPUTS, instead
  6101 isatool document copies the Isabelle style files to the target
  6102 location;
  6103 
  6104 
  6105 *** Isar ***
  6106 
  6107 * Pure/Provers: improved proof by cases and induction;
  6108   - 'case' command admits impromptu naming of parameters (such as
  6109     "case (Suc n)");
  6110   - 'induct' method divinates rule instantiation from the inductive
  6111     claim; no longer requires excessive ?P bindings for proper
  6112     instantiation of cases;
  6113   - 'induct' method properly enumerates all possibilities of set/type
  6114     rules; as a consequence facts may be also passed through *type*
  6115     rules without further ado;
  6116   - 'induct' method now derives symbolic cases from the *rulified*
  6117     rule (before it used to rulify cases stemming from the internal
  6118     atomized version); this means that the context of a non-atomic
  6119     statement becomes is included in the hypothesis, avoiding the
  6120     slightly cumbersome show "PROP ?case" form;
  6121   - 'induct' may now use elim-style induction rules without chaining
  6122     facts, using ``missing'' premises from the goal state; this allows
  6123     rules stemming from inductive sets to be applied in unstructured
  6124     scripts, while still benefitting from proper handling of non-atomic
  6125     statements; NB: major inductive premises need to be put first, all
  6126     the rest of the goal is passed through the induction;
  6127   - 'induct' proper support for mutual induction involving non-atomic
  6128     rule statements (uses the new concept of simultaneous goals, see
  6129     below);
  6130   - append all possible rule selections, but only use the first
  6131     success (no backtracking);
  6132   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  6133   - undeclared rule case names default to numbers 1, 2, 3, ...;
  6134   - added 'print_induct_rules' (covered by help item in recent Proof
  6135     General versions);
  6136   - moved induct/cases attributes to Pure, methods to Provers;
  6137   - generic method setup instantiated for FOL and HOL;
  6138 
  6139 * Pure: support multiple simultaneous goal statements, for example
  6140 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  6141 meta-level mechanism, this acts as if several individual goals had
  6142 been stated separately; in particular common proof methods need to be
  6143 repeated in order to cover all claims; note that a single elimination
  6144 step is *not* sufficient to establish the two conjunctions, so this
  6145 fails:
  6146 
  6147   assume "A & B" then have A and B ..   (*".." fails*)
  6148 
  6149 better use "obtain" in situations as above; alternative refer to
  6150 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  6151 
  6152 * Pure: proper integration with ``locales''; unlike the original
  6153 version by Florian Kammller, Isar locales package high-level proof
  6154 contexts rather than raw logical ones (e.g. we admit to include
  6155 attributes everywhere); operations on locales include merge and
  6156 rename; support for implicit arguments (``structures''); simultaneous
  6157 type-inference over imports and text; see also HOL/ex/Locales.thy for
  6158 some examples;
  6159 
  6160 * Pure: the following commands have been ``localized'', supporting a
  6161 target locale specification "(in name)": 'lemma', 'theorem',
  6162 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  6163 stored both within the locale and at the theory level (exported and
  6164 qualified by the locale name);
  6165 
  6166 * Pure: theory goals may now be specified in ``long'' form, with
  6167 ad-hoc contexts consisting of arbitrary locale elements. for example
  6168 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  6169 definitions may be given, too); the result is a meta-level rule with
  6170 the context elements being discharged in the obvious way;
  6171 
  6172 * Pure: new proof command 'using' allows to augment currently used
  6173 facts after a goal statement ('using' is syntactically analogous to
  6174 'apply', but acts on the goal's facts only); this allows chained facts
  6175 to be separated into parts given before and after a claim, as in
  6176 ``from a and b have C using d and e <proof>'';
  6177 
  6178 * Pure: renamed "antecedent" case to "rule_context";
  6179 
  6180 * Pure: new 'judgment' command records explicit information about the
  6181 object-logic embedding (used by several tools internally); no longer
  6182 use hard-wired "Trueprop";
  6183 
  6184 * Pure: added 'corollary' command;
  6185 
  6186 * Pure: fixed 'token_translation' command;
  6187 
  6188 * Pure: removed obsolete 'exported' attribute;
  6189 
  6190 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  6191 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  6192 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  6193 
  6194 * Pure: method 'atomize' presents local goal premises as object-level
  6195 statements (atomic meta-level propositions); setup controlled via
  6196 rewrite rules declarations of 'atomize' attribute; example
  6197 application: 'induct' method with proper rule statements in improper
  6198 proof *scripts*;
  6199 
  6200 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  6201 now consider the syntactic context of assumptions, giving a better
  6202 chance to get type-inference of the arguments right (this is
  6203 especially important for locales);
  6204 
  6205 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  6206 mode;
  6207 
  6208 * Pure/obtain: the formal conclusion "thesis", being marked as
  6209 ``internal'', may no longer be reference directly in the text;
  6210 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  6211 situations;
  6212 
  6213 * Pure: generic 'sym' attribute which declares a rule both as pure
  6214 'elim?' and for the 'symmetric' operation;
  6215 
  6216 * Pure: marginal comments ``--'' may now occur just anywhere in the
  6217 text; the fixed correlation with particular command syntax has been
  6218 discontinued;
  6219 
  6220 * Pure: new method 'rules' is particularly well-suited for proof
  6221 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  6222 but often produces more compact proof terms with less detours;
  6223 
  6224 * Pure/Provers/classical: simplified integration with pure rule
  6225 attributes and methods; the classical "intro?/elim?/dest?"
  6226 declarations coincide with the pure ones; the "rule" method no longer
  6227 includes classically swapped intros; "intro" and "elim" methods no
  6228 longer pick rules from the context; also got rid of ML declarations
  6229 AddXIs/AddXEs/AddXDs; all of this has some potential for
  6230 INCOMPATIBILITY;