NEWS
author haftmann
Mon Jul 18 21:34:01 2011 +0200 (2011-07-18)
changeset 43899 60ef6abb2f92
parent 43873 8a2f339641c1
child 43940 26ca0bad226a
permissions -rw-r--r--
avoid misunderstandable 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   INF_subset ~> INF_superset_mono
    75   INFI_bool_eq ~> INF_bool_eq
    76   SUPR_bool_eq ~> SUP_bool_eq
    77   INFI_apply ~> INF_apply
    78   SUPR_apply ~> SUP_apply
    79 INCOMPATIBILITY.
    80 
    81 * Archimedian_Field.thy:
    82     floor now is defined as parameter of a separate type class floor_ceiling.
    83  
    84 * Finite_Set.thy: more coherent development of fold_set locales:
    85 
    86     locale fun_left_comm ~> locale comp_fun_commute
    87     locale fun_left_comm_idem ~> locale comp_fun_idem
    88     
    89 Both use point-free characterisation; interpretation proofs may need adjustment.
    90 INCOMPATIBILITY.
    91 
    92 * Code generation:
    93   - theory Library/Code_Char_ord provides native ordering of characters
    94     in the target language.
    95     
    96 * Declare ext [intro] by default.  Rare INCOMPATIBILITY.
    97 
    98 * Nitpick:
    99   - Added "need" and "total_consts" options.
   100   - Reintroduced "show_skolems" option by popular demand.
   101   - Renamed attribute: nitpick_def ~> nitpick_unfold.
   102     INCOMPATIBILITY.
   103 
   104 * Sledgehammer:
   105   - sledgehammer available_provers ~> sledgehammer supported_provers.
   106     INCOMPATIBILITY.
   107   - Added support for SNARK and ToFoF-E on SystemOnTPTP and for simply typed
   108     TPTP problems (TFF).
   109   - Added "preplay_timeout", "slicing", "type_enc", "sound", "max_mono_iters",
   110     and "max_new_mono_instances" options.
   111   - Removed "explicit_apply" and "full_types" options as well as "Full Types"
   112     Proof General menu item. INCOMPATIBILITY.
   113 
   114 * Metis:
   115   - Removed "metisF" -- use "metis" instead. INCOMPATIBILITY.
   116   - Obsoleted "metisFT" -- use "metis (full_types)" instead. INCOMPATIBILITY.
   117 
   118 * "try":
   119   - Renamed "try_methods" and added "simp:", "intro:", "dest:", and "elim:"
   120     options. INCOMPATIBILITY.
   121   - Introduced "try" that not only runs "try_methods" but also "solve_direct",
   122     "sledgehammer", "quickcheck", and "nitpick".
   123 
   124 * Quickcheck:
   125   - Added "eval" option to evaluate terms for the found counterexample
   126     (currently only supported by the default (exhaustive) tester)
   127   - Added post-processing of terms to obtain readable counterexamples
   128     (currently only supported by the default (exhaustive) tester)
   129   - New counterexample generator quickcheck[narrowing] enables
   130     narrowing-based testing.
   131     It requires that the Glasgow Haskell compiler is installed and
   132     its location is known to Isabelle with the environment variable
   133     ISABELLE_GHC.
   134 
   135 * Function package: discontinued option "tailrec".
   136 INCOMPATIBILITY. Use partial_function instead.
   137 
   138 * HOL-Probability:
   139   - Caratheodory's extension lemma is now proved for ring_of_sets.
   140   - Infinite products of probability measures are now available.
   141   - Use extended reals instead of positive extended reals.
   142     INCOMPATIBILITY.
   143 
   144 
   145 *** Document preparation ***
   146 
   147 * Discontinued special treatment of hard tabulators, which are better
   148 avoided in the first place.  Implicit tab-width is 1.
   149 
   150 * Antiquotation @{rail} layouts railroad syntax diagrams, see also
   151 isar-ref manual.
   152 
   153 * Antiquotation @{value} evaluates the given term and presents its result.
   154 
   155 * Localized \isabellestyle switch can be used within blocks or groups
   156 like this:
   157 
   158   \isabellestyle{it}  %preferred default
   159   {\isabellestylett @{text "typewriter stuff"}}
   160 
   161 * New term style "isub" as ad-hoc conversion of variables x1, y23 into
   162 subscripted form x\<^isub>1, y\<^isub>2\<^isub>3.
   163 
   164 * Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
   165 (e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).
   166 
   167 
   168 *** ML ***
   169 
   170 * The inner syntax of sort/type/term/prop supports inlined YXML
   171 representations within quoted string tokens.  By encoding logical
   172 entities via Term_XML (in ML or Scala) concrete syntax can be
   173 bypassed, which is particularly useful for producing bits of text
   174 under external program control.
   175 
   176 * Antiquotations for ML and document preparation are managed as theory
   177 data, which requires explicit setup.
   178 
   179 * Isabelle_Process.is_active allows tools to check if the official
   180 process wrapper is running (Isabelle/Scala/jEdit) or the old TTY loop
   181 (better known as Proof General).
   182 
   183 * Structure Proof_Context follows standard naming scheme.  Old
   184 ProofContext is still available for some time as legacy alias.
   185 
   186 * Structure Timing provides various operations for timing; supersedes
   187 former start_timing/end_timing etc.
   188 
   189 * Path.print is the official way to show file-system paths to users
   190 (including quotes etc.).
   191 
   192 * Inner syntax: identifiers in parse trees of generic categories
   193 "logic", "aprop", "idt" etc. carry position information (disguised as
   194 type constraints).  Occasional INCOMPATIBILITY with non-compliant
   195 translations that choke on unexpected type constraints.  Positions can
   196 be stripped in ML translations via Syntax.strip_positions /
   197 Syntax.strip_positions_ast, or via the syntax constant
   198 "_strip_positions" within parse trees.  As last resort, positions can
   199 be disabled via the configuration option Syntax.positions, which is
   200 called "syntax_positions" in Isar attribute syntax.
   201 
   202 * Discontinued special status of various ML structures that contribute
   203 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
   204 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
   205 refer directly to Ast.Constant, Lexicon.is_identifier,
   206 Syntax_Trans.mk_binder_tr etc.
   207 
   208 * Typed print translation: discontinued show_sorts argument, which is
   209 already available via context of "advanced" translation.
   210 
   211 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
   212 goal states; body tactic needs to address all subgoals uniformly.
   213 
   214 * Slightly more special eq_list/eq_set, with shortcut involving
   215 pointer equality (assumes that eq relation is reflexive).
   216 
   217 * Classical tactics use proper Proof.context instead of historic types
   218 claset/clasimpset.  Old-style declarations like addIs, addEs, addDs
   219 operate directly on Proof.context.  Raw type claset retains its use as
   220 snapshot of the classical context, which can be recovered via
   221 (put_claset HOL_cs) etc.  Type clasimpset has been discontinued.
   222 INCOMPATIBILITY, classical tactics and derived proof methods require
   223 proper Proof.context.
   224 
   225 * Scala layer provides JVM method invocation service for static
   226 methods of type (String)String, see Invoke_Scala.method in ML.
   227 For example:
   228 
   229   Invoke_Scala.method "java.lang.System.getProperty" "java.home"
   230 
   231 
   232 
   233 New in Isabelle2011 (January 2011)
   234 ----------------------------------
   235 
   236 *** General ***
   237 
   238 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
   239 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
   240 useful tooltips and hyperlinks produced from its static analysis.  The
   241 bundled component provides an executable Isabelle tool that can be run
   242 like this:
   243 
   244   Isabelle2011/bin/isabelle jedit
   245 
   246 * Significantly improved Isabelle/Isar implementation manual.
   247 
   248 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
   249 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
   250 while the default heap location within that directory lacks that extra
   251 suffix.  This isolates multiple Isabelle installations from each
   252 other, avoiding problems with old settings in new versions.
   253 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
   254 
   255 * Source files are always encoded as UTF-8, instead of old-fashioned
   256 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
   257 the following package declarations:
   258 
   259   \usepackage[utf8]{inputenc}
   260   \usepackage{textcomp}
   261 
   262 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
   263 a Unicode character is treated as a single symbol, not a sequence of
   264 non-ASCII bytes as before.  Since Isabelle/ML string literals may
   265 contain symbols without further backslash escapes, Unicode can now be
   266 used here as well.  Recall that Symbol.explode in ML provides a
   267 consistent view on symbols, while raw explode (or String.explode)
   268 merely give a byte-oriented representation.
   269 
   270 * Theory loader: source files are primarily located via the master
   271 directory of each theory node (where the .thy file itself resides).
   272 The global load path is still partially available as legacy feature.
   273 Minor INCOMPATIBILITY due to subtle change in file lookup: use
   274 explicit paths, relatively to the theory.
   275 
   276 * Special treatment of ML file names has been discontinued.
   277 Historically, optional extensions .ML or .sml were added on demand --
   278 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
   279 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
   280 
   281 * Various options that affect pretty printing etc. are now properly
   282 handled within the context via configuration options, instead of
   283 unsynchronized references or print modes.  There are both ML Config.T
   284 entities and Isar declaration attributes to access these.
   285 
   286   ML (Config.T)                 Isar (attribute)
   287 
   288   eta_contract                  eta_contract
   289   show_brackets                 show_brackets
   290   show_sorts                    show_sorts
   291   show_types                    show_types
   292   show_question_marks           show_question_marks
   293   show_consts                   show_consts
   294   show_abbrevs                  show_abbrevs
   295 
   296   Syntax.ast_trace              syntax_ast_trace
   297   Syntax.ast_stat               syntax_ast_stat
   298   Syntax.ambiguity_level        syntax_ambiguity_level
   299 
   300   Goal_Display.goals_limit      goals_limit
   301   Goal_Display.show_main_goal   show_main_goal
   302 
   303   Method.rule_trace             rule_trace
   304 
   305   Thy_Output.display            thy_output_display
   306   Thy_Output.quotes             thy_output_quotes
   307   Thy_Output.indent             thy_output_indent
   308   Thy_Output.source             thy_output_source
   309   Thy_Output.break              thy_output_break
   310 
   311 Note that corresponding "..._default" references in ML may only be
   312 changed globally at the ROOT session setup, but *not* within a theory.
   313 The option "show_abbrevs" supersedes the former print mode
   314 "no_abbrevs" with inverted meaning.
   315 
   316 * More systematic naming of some configuration options.
   317 INCOMPATIBILITY.
   318 
   319   trace_simp  ~>  simp_trace
   320   debug_simp  ~>  simp_debug
   321 
   322 * Support for real valued configuration options, using simplistic
   323 floating-point notation that coincides with the inner syntax for
   324 float_token.
   325 
   326 * Support for real valued preferences (with approximative PGIP type):
   327 front-ends need to accept "pgint" values in float notation.
   328 INCOMPATIBILITY.
   329 
   330 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
   331 DejaVu Sans.
   332 
   333 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   334 
   335 
   336 *** Pure ***
   337 
   338 * Command 'type_synonym' (with single argument) replaces somewhat
   339 outdated 'types', which is still available as legacy feature for some
   340 time.
   341 
   342 * Command 'nonterminal' (with 'and' separated list of arguments)
   343 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
   344 
   345 * Command 'notepad' replaces former 'example_proof' for
   346 experimentation in Isar without any result.  INCOMPATIBILITY.
   347 
   348 * Locale interpretation commands 'interpret' and 'sublocale' accept
   349 lists of equations to map definitions in a locale to appropriate
   350 entities in the context of the interpretation.  The 'interpretation'
   351 command already provided this functionality.
   352 
   353 * Diagnostic command 'print_dependencies' prints the locale instances
   354 that would be activated if the specified expression was interpreted in
   355 the current context.  Variant "print_dependencies!" assumes a context
   356 without interpretations.
   357 
   358 * Diagnostic command 'print_interps' prints interpretations in proofs
   359 in addition to interpretations in theories.
   360 
   361 * Discontinued obsolete 'global' and 'local' commands to manipulate
   362 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
   363 Sign.root_path and Sign.local_path may be applied directly where this
   364 feature is still required for historical reasons.
   365 
   366 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
   367 'definition' instead.
   368 
   369 * The "prems" fact, which refers to the accidental collection of
   370 foundational premises in the context, is now explicitly marked as
   371 legacy feature and will be discontinued soon.  Consider using "assms"
   372 of the head statement or reference facts by explicit names.
   373 
   374 * Document antiquotations @{class} and @{type} print classes and type
   375 constructors.
   376 
   377 * Document antiquotation @{file} checks file/directory entries within
   378 the local file system.
   379 
   380 
   381 *** HOL ***
   382 
   383 * Coercive subtyping: functions can be declared as coercions and type
   384 inference will add them as necessary upon input of a term.  Theory
   385 Complex_Main declares real :: nat => real and real :: int => real as
   386 coercions. A coercion function f is declared like this:
   387 
   388   declare [[coercion f]]
   389 
   390 To lift coercions through type constructors (e.g. from nat => real to
   391 nat list => real list), map functions can be declared, e.g.
   392 
   393   declare [[coercion_map map]]
   394 
   395 Currently coercion inference is activated only in theories including
   396 real numbers, i.e. descendants of Complex_Main.  This is controlled by
   397 the configuration option "coercion_enabled", e.g. it can be enabled in
   398 other theories like this:
   399 
   400   declare [[coercion_enabled]]
   401 
   402 * Command 'partial_function' provides basic support for recursive
   403 function definitions over complete partial orders.  Concrete instances
   404 are provided for i) the option type, ii) tail recursion on arbitrary
   405 types, and iii) the heap monad of Imperative_HOL.  See
   406 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
   407 for examples.
   408 
   409 * Function package: f.psimps rules are no longer implicitly declared
   410 as [simp].  INCOMPATIBILITY.
   411 
   412 * Datatype package: theorems generated for executable equality (class
   413 "eq") carry proper names and are treated as default code equations.
   414 
   415 * Inductive package: now offers command 'inductive_simps' to
   416 automatically derive instantiated and simplified equations for
   417 inductive predicates, similar to 'inductive_cases'.
   418 
   419 * Command 'enriched_type' allows to register properties of the
   420 functorial structure of types.
   421 
   422 * Improved infrastructure for term evaluation using code generator
   423 techniques, in particular static evaluation conversions.
   424 
   425 * Code generator: Scala (2.8 or higher) has been added to the target
   426 languages.
   427 
   428 * Code generator: globbing constant expressions "*" and "Theory.*"
   429 have been replaced by the more idiomatic "_" and "Theory._".
   430 INCOMPATIBILITY.
   431 
   432 * Code generator: export_code without explicit file declaration prints
   433 to standard output.  INCOMPATIBILITY.
   434 
   435 * Code generator: do not print function definitions for case
   436 combinators any longer.
   437 
   438 * Code generator: simplification with rules determined with
   439 src/Tools/Code/code_simp.ML and method "code_simp".
   440 
   441 * Code generator for records: more idiomatic representation of record
   442 types.  Warning: records are not covered by ancient SML code
   443 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
   444 rep_datatype declaration helps to succeed then:
   445 
   446   record 'a foo = ...
   447   ...
   448   rep_datatype foo_ext ...
   449 
   450 * Records: logical foundation type for records does not carry a
   451 '_type' suffix any longer (obsolete due to authentic syntax).
   452 INCOMPATIBILITY.
   453 
   454 * Quickcheck now by default uses exhaustive testing instead of random
   455 testing.  Random testing can be invoked by "quickcheck [random]",
   456 exhaustive testing by "quickcheck [exhaustive]".
   457 
   458 * Quickcheck instantiates polymorphic types with small finite
   459 datatypes by default. This enables a simple execution mechanism to
   460 handle quantifiers and function equality over the finite datatypes.
   461 
   462 * Quickcheck random generator has been renamed from "code" to
   463 "random".  INCOMPATIBILITY.
   464 
   465 * Quickcheck now has a configurable time limit which is set to 30
   466 seconds by default. This can be changed by adding [timeout = n] to the
   467 quickcheck command. The time limit for Auto Quickcheck is still set
   468 independently.
   469 
   470 * Quickcheck in locales considers interpretations of that locale for
   471 counter example search.
   472 
   473 * Sledgehammer:
   474   - Added "smt" and "remote_smt" provers based on the "smt" proof
   475     method. See the Sledgehammer manual for details ("isabelle doc
   476     sledgehammer").
   477   - Renamed commands:
   478     sledgehammer atp_info ~> sledgehammer running_provers
   479     sledgehammer atp_kill ~> sledgehammer kill_provers
   480     sledgehammer available_atps ~> sledgehammer available_provers
   481     INCOMPATIBILITY.
   482   - Renamed options:
   483     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
   484     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
   485     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
   486     (and "ms" and "min" are no longer supported)
   487     INCOMPATIBILITY.
   488 
   489 * Nitpick:
   490   - Renamed options:
   491     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
   492     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
   493     INCOMPATIBILITY.
   494   - Added support for partial quotient types.
   495   - Added local versions of the "Nitpick.register_xxx" functions.
   496   - Added "whack" option.
   497   - Allow registration of quotient types as codatatypes.
   498   - Improved "merge_type_vars" option to merge more types.
   499   - Removed unsound "fast_descrs" option.
   500   - Added custom symmetry breaking for datatypes, making it possible to reach
   501     higher cardinalities.
   502   - Prevent the expansion of too large definitions.
   503 
   504 * Proof methods "metis" and "meson" now have configuration options
   505 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
   506 to diagnose these tools. E.g.
   507 
   508     using [[metis_trace = true]]
   509 
   510 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
   511 manually as command 'solve_direct'.
   512 
   513 * The default SMT solver Z3 must be enabled explicitly (due to
   514 licensing issues) by setting the environment variable
   515 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
   516 commercial applications, the SMT solver CVC3 is provided as fall-back;
   517 changing the SMT solver is done via the configuration option
   518 "smt_solver".
   519 
   520 * Remote SMT solvers need to be referred to by the "remote_" prefix,
   521 i.e. "remote_cvc3" and "remote_z3".
   522 
   523 * Added basic SMT support for datatypes, records, and typedefs using
   524 the oracle mode (no proofs).  Direct support of pairs has been dropped
   525 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
   526 support for a similar behavior).  Minor INCOMPATIBILITY.
   527 
   528 * Changed SMT configuration options:
   529   - Renamed:
   530     z3_proofs ~> smt_oracle (with inverted meaning)
   531     z3_trace_assms ~> smt_trace_used_facts
   532     INCOMPATIBILITY.
   533   - Added:
   534     smt_verbose
   535     smt_random_seed
   536     smt_datatypes
   537     smt_infer_triggers
   538     smt_monomorph_limit
   539     cvc3_options
   540     remote_cvc3_options
   541     remote_z3_options
   542     yices_options
   543 
   544 * Boogie output files (.b2i files) need to be declared in the theory
   545 header.
   546 
   547 * Simplification procedure "list_to_set_comprehension" rewrites list
   548 comprehensions applied to List.set to set comprehensions.  Occasional
   549 INCOMPATIBILITY, may be deactivated like this:
   550 
   551   declare [[simproc del: list_to_set_comprehension]]
   552 
   553 * Removed old version of primrec package.  INCOMPATIBILITY.
   554 
   555 * Removed simplifier congruence rule of "prod_case", as has for long
   556 been the case with "split".  INCOMPATIBILITY.
   557 
   558 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
   559 
   560 * Removed [split_format ... and ... and ...] version of
   561 [split_format].  Potential INCOMPATIBILITY.
   562 
   563 * Predicate "sorted" now defined inductively, with nice induction
   564 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
   565 
   566 * Constant "contents" renamed to "the_elem", to free the generic name
   567 contents for other uses.  INCOMPATIBILITY.
   568 
   569 * Renamed class eq and constant eq (for code generation) to class
   570 equal and constant equal, plus renaming of related facts and various
   571 tuning.  INCOMPATIBILITY.
   572 
   573 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
   574 
   575 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
   576 INCOMPATIBILITY.
   577 
   578 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
   579 avoid confusion with finite sets.  INCOMPATIBILITY.
   580 
   581 * Abandoned locales equiv, congruent and congruent2 for equivalence
   582 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
   583 for congruent(2)).
   584 
   585 * Some previously unqualified names have been qualified:
   586 
   587   types
   588     bool ~> HOL.bool
   589     nat ~> Nat.nat
   590 
   591   constants
   592     Trueprop ~> HOL.Trueprop
   593     True ~> HOL.True
   594     False ~> HOL.False
   595     op & ~> HOL.conj
   596     op | ~> HOL.disj
   597     op --> ~> HOL.implies
   598     op = ~> HOL.eq
   599     Not ~> HOL.Not
   600     The ~> HOL.The
   601     All ~> HOL.All
   602     Ex ~> HOL.Ex
   603     Ex1 ~> HOL.Ex1
   604     Let ~> HOL.Let
   605     If ~> HOL.If
   606     Ball ~> Set.Ball
   607     Bex ~> Set.Bex
   608     Suc ~> Nat.Suc
   609     Pair ~> Product_Type.Pair
   610     fst ~> Product_Type.fst
   611     snd ~> Product_Type.snd
   612     curry ~> Product_Type.curry
   613     op : ~> Set.member
   614     Collect ~> Set.Collect
   615 
   616 INCOMPATIBILITY.
   617 
   618 * More canonical naming convention for some fundamental definitions:
   619 
   620     bot_bool_eq ~> bot_bool_def
   621     top_bool_eq ~> top_bool_def
   622     inf_bool_eq ~> inf_bool_def
   623     sup_bool_eq ~> sup_bool_def
   624     bot_fun_eq  ~> bot_fun_def
   625     top_fun_eq  ~> top_fun_def
   626     inf_fun_eq  ~> inf_fun_def
   627     sup_fun_eq  ~> sup_fun_def
   628 
   629 INCOMPATIBILITY.
   630 
   631 * More stylized fact names:
   632 
   633   expand_fun_eq ~> fun_eq_iff
   634   expand_set_eq ~> set_eq_iff
   635   set_ext       ~> set_eqI
   636   nat_number    ~> eval_nat_numeral
   637 
   638 INCOMPATIBILITY.
   639 
   640 * Refactoring of code-generation specific operations in theory List:
   641 
   642   constants
   643     null ~> List.null
   644 
   645   facts
   646     mem_iff ~> member_def
   647     null_empty ~> null_def
   648 
   649 INCOMPATIBILITY.  Note that these were not supposed to be used
   650 regularly unless for striking reasons; their main purpose was code
   651 generation.
   652 
   653 Various operations from the Haskell prelude are used for generating
   654 Haskell code.
   655 
   656 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
   657 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
   658 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
   659 
   660 * Abolished some non-alphabetic type names: "prod" and "sum" replace
   661 "*" and "+" respectively.  INCOMPATIBILITY.
   662 
   663 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
   664 "Sum_Type.Plus" instead.
   665 
   666 * Constant "split" has been merged with constant "prod_case"; names of
   667 ML functions, facts etc. involving split have been retained so far,
   668 though.  INCOMPATIBILITY.
   669 
   670 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
   671 instead.  INCOMPATIBILITY.
   672 
   673 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
   674 INCOMPATIBILITY.
   675 
   676 * Former theory Library/Enum is now part of the HOL-Main image.
   677 INCOMPATIBILITY: all constants of the Enum theory now have to be
   678 referred to by its qualified name.
   679 
   680   enum    ~>  Enum.enum
   681   nlists  ~>  Enum.nlists
   682   product ~>  Enum.product
   683 
   684 * Theory Library/Monad_Syntax provides do-syntax for monad types.
   685 Syntax in Library/State_Monad has been changed to avoid ambiguities.
   686 INCOMPATIBILITY.
   687 
   688 * Theory Library/SetsAndFunctions has been split into
   689 Library/Function_Algebras and Library/Set_Algebras; canonical names
   690 for instance definitions for functions; various improvements.
   691 INCOMPATIBILITY.
   692 
   693 * Theory Library/Multiset provides stable quicksort implementation of
   694 sort_key.
   695 
   696 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
   697 INCOMPATIBILITY.
   698 
   699 * Session Multivariate_Analysis: introduced a type class for euclidean
   700 space.  Most theorems are now stated in terms of euclidean spaces
   701 instead of finite cartesian products.
   702 
   703   types
   704     real ^ 'n ~>  'a::real_vector
   705               ~>  'a::euclidean_space
   706               ~>  'a::ordered_euclidean_space
   707         (depends on your needs)
   708 
   709   constants
   710      _ $ _        ~> _ $$ _
   711      \<chi> x. _  ~> \<chi>\<chi> x. _
   712      CARD('n)     ~> DIM('a)
   713 
   714 Also note that the indices are now natural numbers and not from some
   715 finite type. Finite cartesian products of euclidean spaces, products
   716 of euclidean spaces the real and complex numbers are instantiated to
   717 be euclidean_spaces.  INCOMPATIBILITY.
   718 
   719 * Session Probability: introduced pextreal as positive extended real
   720 numbers.  Use pextreal as value for measures.  Introduce the
   721 Radon-Nikodym derivative, product spaces and Fubini's theorem for
   722 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
   723 the integral in Multivariate Analysis.  INCOMPATIBILITY.
   724 
   725 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   726 INCOMPATIBILITY.
   727 
   728 * Session SPARK (with image HOL-SPARK) provides commands to load and
   729 prove verification conditions generated by the SPARK Ada program
   730 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
   731 
   732 
   733 *** HOL-Algebra ***
   734 
   735 * Theorems for additive ring operations (locale abelian_monoid and
   736 descendants) are generated by interpretation from their multiplicative
   737 counterparts.  Names (in particular theorem names) have the mandatory
   738 qualifier 'add'.  Previous theorem names are redeclared for
   739 compatibility.
   740 
   741 * Structure "int_ring" is now an abbreviation (previously a
   742 definition).  This fits more natural with advanced interpretations.
   743 
   744 
   745 *** HOLCF ***
   746 
   747 * The domain package now runs in definitional mode by default: The
   748 former command 'new_domain' is now called 'domain'.  To use the domain
   749 package in its original axiomatic mode, use 'domain (unsafe)'.
   750 INCOMPATIBILITY.
   751 
   752 * The new class "domain" is now the default sort.  Class "predomain"
   753 is an unpointed version of "domain". Theories can be updated by
   754 replacing sort annotations as shown below.  INCOMPATIBILITY.
   755 
   756   'a::type ~> 'a::countable
   757   'a::cpo  ~> 'a::predomain
   758   'a::pcpo ~> 'a::domain
   759 
   760 * The old type class "rep" has been superseded by class "domain".
   761 Accordingly, users of the definitional package must remove any
   762 "default_sort rep" declarations.  INCOMPATIBILITY.
   763 
   764 * The domain package (definitional mode) now supports unpointed
   765 predomain argument types, as long as they are marked 'lazy'. (Strict
   766 arguments must be in class "domain".) For example, the following
   767 domain definition now works:
   768 
   769   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
   770 
   771 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
   772 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
   773 'a option, and 'a list.  Additionally, it configures fixrec and the
   774 domain package to work with these types.  For example:
   775 
   776   fixrec isInl :: "('a + 'b) u -> tr"
   777     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
   778 
   779   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
   780 
   781 * The "(permissive)" option of fixrec has been replaced with a
   782 per-equation "(unchecked)" option. See
   783 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
   784 
   785 * The "bifinite" class no longer fixes a constant "approx"; the class
   786 now just asserts that such a function exists.  INCOMPATIBILITY.
   787 
   788 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
   789 defines an embedding of type 'a defl into udom by default; instances
   790 of "bifinite" and "domain" classes are available in
   791 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
   792 
   793 * The syntax "REP('a)" has been replaced with "DEFL('a)".
   794 
   795 * The predicate "directed" has been removed.  INCOMPATIBILITY.
   796 
   797 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
   798 
   799 * The function "cprod_map" has been renamed to "prod_map".
   800 INCOMPATIBILITY.
   801 
   802 * The monadic bind operator on each powerdomain has new binder syntax
   803 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
   804 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
   805 
   806 * The infix syntax for binary union on each powerdomain has changed
   807 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
   808 syntax.  INCOMPATIBILITY.
   809 
   810 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
   811 still supported as an input translation.
   812 
   813 * Renamed some theorems (the original names are also still available).
   814 
   815   expand_fun_below   ~> fun_below_iff
   816   below_fun_ext      ~> fun_belowI
   817   expand_cfun_eq     ~> cfun_eq_iff
   818   ext_cfun           ~> cfun_eqI
   819   expand_cfun_below  ~> cfun_below_iff
   820   below_cfun_ext     ~> cfun_belowI
   821   cont2cont_Rep_CFun ~> cont2cont_APP
   822 
   823 * The Abs and Rep functions for various types have changed names.
   824 Related theorem names have also changed to match. INCOMPATIBILITY.
   825 
   826   Rep_CFun  ~> Rep_cfun
   827   Abs_CFun  ~> Abs_cfun
   828   Rep_Sprod ~> Rep_sprod
   829   Abs_Sprod ~> Abs_sprod
   830   Rep_Ssum  ~> Rep_ssum
   831   Abs_Ssum  ~> Abs_ssum
   832 
   833 * Lemmas with names of the form *_defined_iff or *_strict_iff have
   834 been renamed to *_bottom_iff.  INCOMPATIBILITY.
   835 
   836 * Various changes to bisimulation/coinduction with domain package:
   837 
   838   - Definitions of "bisim" constants no longer mention definedness.
   839   - With mutual recursion, "bisim" predicate is now curried.
   840   - With mutual recursion, each type gets a separate coind theorem.
   841   - Variable names in bisim_def and coinduct rules have changed.
   842 
   843 INCOMPATIBILITY.
   844 
   845 * Case combinators generated by the domain package for type "foo" are
   846 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
   847 
   848 * Several theorems have been renamed to more accurately reflect the
   849 names of constants and types involved.  INCOMPATIBILITY.
   850 
   851   thelub_const    ~> lub_const
   852   lub_const       ~> is_lub_const
   853   thelubI         ~> lub_eqI
   854   is_lub_lub      ~> is_lubD2
   855   lubI            ~> is_lub_lub
   856   unique_lub      ~> is_lub_unique
   857   is_ub_lub       ~> is_lub_rangeD1
   858   lub_bin_chain   ~> is_lub_bin_chain
   859   lub_fun         ~> is_lub_fun
   860   thelub_fun      ~> lub_fun
   861   thelub_cfun     ~> lub_cfun
   862   thelub_Pair     ~> lub_Pair
   863   lub_cprod       ~> is_lub_prod
   864   thelub_cprod    ~> lub_prod
   865   minimal_cprod   ~> minimal_prod
   866   inst_cprod_pcpo ~> inst_prod_pcpo
   867   UU_I            ~> bottomI
   868   compact_UU      ~> compact_bottom
   869   deflation_UU    ~> deflation_bottom
   870   finite_deflation_UU ~> finite_deflation_bottom
   871 
   872 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
   873 
   874   sq_ord_less_eq_trans ~> below_eq_trans
   875   sq_ord_eq_less_trans ~> eq_below_trans
   876   refl_less            ~> below_refl
   877   trans_less           ~> below_trans
   878   antisym_less         ~> below_antisym
   879   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
   880   box_less             ~> box_below
   881   rev_trans_less       ~> rev_below_trans
   882   not_less2not_eq      ~> not_below2not_eq
   883   less_UU_iff          ~> below_UU_iff
   884   flat_less_iff        ~> flat_below_iff
   885   adm_less             ~> adm_below
   886   adm_not_less         ~> adm_not_below
   887   adm_compact_not_less ~> adm_compact_not_below
   888   less_fun_def         ~> below_fun_def
   889   expand_fun_less      ~> fun_below_iff
   890   less_fun_ext         ~> fun_belowI
   891   less_discr_def       ~> below_discr_def
   892   discr_less_eq        ~> discr_below_eq
   893   less_unit_def        ~> below_unit_def
   894   less_cprod_def       ~> below_prod_def
   895   prod_lessI           ~> prod_belowI
   896   Pair_less_iff        ~> Pair_below_iff
   897   fst_less_iff         ~> fst_below_iff
   898   snd_less_iff         ~> snd_below_iff
   899   expand_cfun_less     ~> cfun_below_iff
   900   less_cfun_ext        ~> cfun_belowI
   901   injection_less       ~> injection_below
   902   less_up_def          ~> below_up_def
   903   not_Iup_less         ~> not_Iup_below
   904   Iup_less             ~> Iup_below
   905   up_less              ~> up_below
   906   Def_inject_less_eq   ~> Def_below_Def
   907   Def_less_is_eq       ~> Def_below_iff
   908   spair_less_iff       ~> spair_below_iff
   909   less_sprod           ~> below_sprod
   910   spair_less           ~> spair_below
   911   sfst_less_iff        ~> sfst_below_iff
   912   ssnd_less_iff        ~> ssnd_below_iff
   913   fix_least_less       ~> fix_least_below
   914   dist_less_one        ~> dist_below_one
   915   less_ONE             ~> below_ONE
   916   ONE_less_iff         ~> ONE_below_iff
   917   less_sinlD           ~> below_sinlD
   918   less_sinrD           ~> below_sinrD
   919 
   920 
   921 *** FOL and ZF ***
   922 
   923 * All constant names are now qualified internally and use proper
   924 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
   925 
   926 
   927 *** ML ***
   928 
   929 * Antiquotation @{assert} inlines a function bool -> unit that raises
   930 Fail if the argument is false.  Due to inlining the source position of
   931 failed assertions is included in the error output.
   932 
   933 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
   934 text is in practice always evaluated with a stable theory checkpoint.
   935 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
   936 
   937 * Antiquotation @{theory A} refers to theory A from the ancestry of
   938 the current context, not any accidental theory loader state as before.
   939 Potential INCOMPATIBILITY, subtle change in semantics.
   940 
   941 * Syntax.pretty_priority (default 0) configures the required priority
   942 of pretty-printed output and thus affects insertion of parentheses.
   943 
   944 * Syntax.default_root (default "any") configures the inner syntax
   945 category (nonterminal symbol) for parsing of terms.
   946 
   947 * Former exception Library.UnequalLengths now coincides with
   948 ListPair.UnequalLengths.
   949 
   950 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
   951 main functionality is provided by structure Simplifier.
   952 
   953 * Renamed raw "explode" function to "raw_explode" to emphasize its
   954 meaning.  Note that internally to Isabelle, Symbol.explode is used in
   955 almost all situations.
   956 
   957 * Discontinued obsolete function sys_error and exception SYS_ERROR.
   958 See implementation manual for further details on exceptions in
   959 Isabelle/ML.
   960 
   961 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
   962 meaning.
   963 
   964 * Renamed structure PureThy to Pure_Thy and moved most of its
   965 operations to structure Global_Theory, to emphasize that this is
   966 rarely-used global-only stuff.
   967 
   968 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
   969 instead (or tracing for high-volume output).
   970 
   971 * Configuration option show_question_marks only affects regular pretty
   972 printing of types and terms, not raw Term.string_of_vname.
   973 
   974 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
   975 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
   976 @{thms} for most purposes.
   977 
   978 * ML structure Unsynchronized is never opened, not even in Isar
   979 interaction mode as before.  Old Unsynchronized.set etc. have been
   980 discontinued -- use plain := instead.  This should be *rare* anyway,
   981 since modern tools always work via official context data, notably
   982 configuration options.
   983 
   984 * Parallel and asynchronous execution requires special care concerning
   985 interrupts.  Structure Exn provides some convenience functions that
   986 avoid working directly with raw Interrupt.  User code must not absorb
   987 interrupts -- intermediate handling (for cleanup etc.) needs to be
   988 followed by re-raising of the original exception.  Another common
   989 source of mistakes are "handle _" patterns, which make the meaning of
   990 the program subject to physical effects of the environment.
   991 
   992 
   993 
   994 New in Isabelle2009-2 (June 2010)
   995 ---------------------------------
   996 
   997 *** General ***
   998 
   999 * Authentic syntax for *all* logical entities (type classes, type
  1000 constructors, term constants): provides simple and robust
  1001 correspondence between formal entities and concrete syntax.  Within
  1002 the parse tree / AST representations, "constants" are decorated by
  1003 their category (class, type, const) and spelled out explicitly with
  1004 their full internal name.
  1005 
  1006 Substantial INCOMPATIBILITY concerning low-level syntax declarations
  1007 and translations (translation rules and translation functions in ML).
  1008 Some hints on upgrading:
  1009 
  1010   - Many existing uses of 'syntax' and 'translations' can be replaced
  1011     by more modern 'type_notation', 'notation' and 'abbreviation',
  1012     which are independent of this issue.
  1013 
  1014   - 'translations' require markup within the AST; the term syntax
  1015     provides the following special forms:
  1016 
  1017       CONST c   -- produces syntax version of constant c from context
  1018       XCONST c  -- literally c, checked as constant from context
  1019       c         -- literally c, if declared by 'syntax'
  1020 
  1021     Plain identifiers are treated as AST variables -- occasionally the
  1022     system indicates accidental variables via the error "rhs contains
  1023     extra variables".
  1024 
  1025     Type classes and type constructors are marked according to their
  1026     concrete syntax.  Some old translations rules need to be written
  1027     for the "type" category, using type constructor application
  1028     instead of pseudo-term application of the default category
  1029     "logic".
  1030 
  1031   - 'parse_translation' etc. in ML may use the following
  1032     antiquotations:
  1033 
  1034       @{class_syntax c}   -- type class c within parse tree / AST
  1035       @{term_syntax c}    -- type constructor c within parse tree / AST
  1036       @{const_syntax c}   -- ML version of "CONST c" above
  1037       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
  1038 
  1039   - Literal types within 'typed_print_translations', i.e. those *not*
  1040     represented as pseudo-terms are represented verbatim.  Use @{class
  1041     c} or @{type_name c} here instead of the above syntax
  1042     antiquotations.
  1043 
  1044 Note that old non-authentic syntax was based on unqualified base
  1045 names, so all of the above "constant" names would coincide.  Recall
  1046 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
  1047 diagnose syntax problems.
  1048 
  1049 * Type constructors admit general mixfix syntax, not just infix.
  1050 
  1051 * Concrete syntax may be attached to local entities without a proof
  1052 body, too.  This works via regular mixfix annotations for 'fix',
  1053 'def', 'obtain' etc. or via the explicit 'write' command, which is
  1054 similar to the 'notation' command in theory specifications.
  1055 
  1056 * Discontinued unnamed infix syntax (legacy feature for many years) --
  1057 need to specify constant name and syntax separately.  Internal ML
  1058 datatype constructors have been renamed from InfixName to Infix etc.
  1059 Minor INCOMPATIBILITY.
  1060 
  1061 * Schematic theorem statements need to be explicitly markup as such,
  1062 via commands 'schematic_lemma', 'schematic_theorem',
  1063 'schematic_corollary'.  Thus the relevance of the proof is made
  1064 syntactically clear, which impacts performance in a parallel or
  1065 asynchronous interactive environment.  Minor INCOMPATIBILITY.
  1066 
  1067 * Use of cumulative prems via "!" in some proof methods has been
  1068 discontinued (old legacy feature).
  1069 
  1070 * References 'trace_simp' and 'debug_simp' have been replaced by
  1071 configuration options stored in the context. Enabling tracing (the
  1072 case of debugging is similar) in proofs works via
  1073 
  1074   using [[trace_simp = true]]
  1075 
  1076 Tracing is then active for all invocations of the simplifier in
  1077 subsequent goal refinement steps. Tracing may also still be enabled or
  1078 disabled via the ProofGeneral settings menu.
  1079 
  1080 * Separate commands 'hide_class', 'hide_type', 'hide_const',
  1081 'hide_fact' replace the former 'hide' KIND command.  Minor
  1082 INCOMPATIBILITY.
  1083 
  1084 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
  1085 more efficient than combinations with -q1 or -q2.
  1086 
  1087 
  1088 *** Pure ***
  1089 
  1090 * Proofterms record type-class reasoning explicitly, using the
  1091 "unconstrain" operation internally.  This eliminates all sort
  1092 constraints from a theorem and proof, introducing explicit
  1093 OFCLASS-premises.  On the proof term level, this operation is
  1094 automatically applied at theorem boundaries, such that closed proofs
  1095 are always free of sort constraints.  INCOMPATIBILITY for tools that
  1096 inspect proof terms.
  1097 
  1098 * Local theory specifications may depend on extra type variables that
  1099 are not present in the result type -- arguments TYPE('a) :: 'a itself
  1100 are added internally.  For example:
  1101 
  1102   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
  1103 
  1104 * Predicates of locales introduced by classes carry a mandatory
  1105 "class" prefix.  INCOMPATIBILITY.
  1106 
  1107 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
  1108 
  1109 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
  1110 'class' instead.
  1111 
  1112 * Command 'code_reflect' allows to incorporate generated ML code into
  1113 runtime environment; replaces immature code_datatype antiquotation.
  1114 INCOMPATIBILITY.
  1115 
  1116 * Code generator: simple concept for abstract datatypes obeying
  1117 invariants.
  1118 
  1119 * Code generator: details of internal data cache have no impact on the
  1120 user space functionality any longer.
  1121 
  1122 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  1123 subgoals.  This is more appropriate for interpretations with 'where'.
  1124 INCOMPATIBILITY.
  1125 
  1126 * Command 'example_proof' opens an empty proof body.  This allows to
  1127 experiment with Isar, without producing any persistent result.
  1128 
  1129 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  1130 within a local theory context, with explicit checking of the
  1131 constructors involved (in contrast to the raw 'syntax' versions).
  1132 
  1133 * Commands 'types' and 'typedecl' now work within a local theory
  1134 context -- without introducing dependencies on parameters or
  1135 assumptions, which is not possible in Isabelle/Pure.
  1136 
  1137 * Command 'defaultsort' has been renamed to 'default_sort', it works
  1138 within a local theory context.  Minor INCOMPATIBILITY.
  1139 
  1140 
  1141 *** HOL ***
  1142 
  1143 * Command 'typedef' now works within a local theory context -- without
  1144 introducing dependencies on parameters or assumptions, which is not
  1145 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  1146 contain multiple interpretations of local typedefs (with different
  1147 non-emptiness proofs), even in a global theory context.
  1148 
  1149 * New package for quotient types.  Commands 'quotient_type' and
  1150 'quotient_definition' may be used for defining types and constants by
  1151 quotient constructions.  An example is the type of integers created by
  1152 quotienting pairs of natural numbers:
  1153 
  1154   fun
  1155     intrel :: "(nat * nat) => (nat * nat) => bool"
  1156   where
  1157     "intrel (x, y) (u, v) = (x + v = u + y)"
  1158 
  1159   quotient_type int = "nat * nat" / intrel
  1160     by (auto simp add: equivp_def expand_fun_eq)
  1161 
  1162   quotient_definition
  1163     "0::int" is "(0::nat, 0::nat)"
  1164 
  1165 The method "lifting" can be used to lift of theorems from the
  1166 underlying "raw" type to the quotient type.  The example
  1167 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  1168 construction and provides a reasoning infrastructure for finite sets.
  1169 
  1170 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  1171 clash with new theory Quotient in Main HOL.
  1172 
  1173 * Moved the SMT binding into the main HOL session, eliminating
  1174 separate HOL-SMT session.
  1175 
  1176 * List membership infix mem operation is only an input abbreviation.
  1177 INCOMPATIBILITY.
  1178 
  1179 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  1180 for future developements; former Library/Word.thy is still present in
  1181 the AFP entry RSAPPS.
  1182 
  1183 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  1184 longer shadowed.  INCOMPATIBILITY.
  1185 
  1186 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  1187 INCOMPATIBILITY.
  1188 
  1189 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  1190 INCOMPATIBILITY.
  1191 
  1192 * Dropped normalizing_semiring etc; use the facts in semiring classes
  1193 instead.  INCOMPATIBILITY.
  1194 
  1195 * Dropped several real-specific versions of lemmas about floor and
  1196 ceiling; use the generic lemmas from theory "Archimedean_Field"
  1197 instead.  INCOMPATIBILITY.
  1198 
  1199   floor_number_of_eq         ~> floor_number_of
  1200   le_floor_eq_number_of      ~> number_of_le_floor
  1201   le_floor_eq_zero           ~> zero_le_floor
  1202   le_floor_eq_one            ~> one_le_floor
  1203   floor_less_eq_number_of    ~> floor_less_number_of
  1204   floor_less_eq_zero         ~> floor_less_zero
  1205   floor_less_eq_one          ~> floor_less_one
  1206   less_floor_eq_number_of    ~> number_of_less_floor
  1207   less_floor_eq_zero         ~> zero_less_floor
  1208   less_floor_eq_one          ~> one_less_floor
  1209   floor_le_eq_number_of      ~> floor_le_number_of
  1210   floor_le_eq_zero           ~> floor_le_zero
  1211   floor_le_eq_one            ~> floor_le_one
  1212   floor_subtract_number_of   ~> floor_diff_number_of
  1213   floor_subtract_one         ~> floor_diff_one
  1214   ceiling_number_of_eq       ~> ceiling_number_of
  1215   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  1216   ceiling_le_zero_eq         ~> ceiling_le_zero
  1217   ceiling_le_eq_one          ~> ceiling_le_one
  1218   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  1219   less_ceiling_eq_zero       ~> zero_less_ceiling
  1220   less_ceiling_eq_one        ~> one_less_ceiling
  1221   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  1222   ceiling_less_eq_zero       ~> ceiling_less_zero
  1223   ceiling_less_eq_one        ~> ceiling_less_one
  1224   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  1225   le_ceiling_eq_zero         ~> zero_le_ceiling
  1226   le_ceiling_eq_one          ~> one_le_ceiling
  1227   ceiling_subtract_number_of ~> ceiling_diff_number_of
  1228   ceiling_subtract_one       ~> ceiling_diff_one
  1229 
  1230 * Theory "Finite_Set": various folding_XXX locales facilitate the
  1231 application of the various fold combinators on finite sets.
  1232 
  1233 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  1234 provides abstract red-black tree type which is backed by "RBT_Impl" as
  1235 implementation.  INCOMPATIBILTY.
  1236 
  1237 * Theory Library/Coinductive_List has been removed -- superseded by
  1238 AFP/thys/Coinductive.
  1239 
  1240 * Theory PReal, including the type "preal" and related operations, has
  1241 been removed.  INCOMPATIBILITY.
  1242 
  1243 * Real: new development using Cauchy Sequences.
  1244 
  1245 * Split off theory "Big_Operators" containing setsum, setprod,
  1246 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  1247 
  1248 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  1249 "Int" etc.  INCOMPATIBILITY.
  1250 
  1251 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  1252 
  1253 * New set of rules "ac_simps" provides combined assoc / commute
  1254 rewrites for all interpretations of the appropriate generic locales.
  1255 
  1256 * Renamed theory "OrderedGroup" to "Groups" and split theory
  1257 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  1258 appropriate and more consistent names suitable for name prefixes
  1259 within the HOL theories.  INCOMPATIBILITY.
  1260 
  1261 * Some generic constants have been put to appropriate theories:
  1262   - less_eq, less: Orderings
  1263   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  1264   - inverse, divide: Rings
  1265 INCOMPATIBILITY.
  1266 
  1267 * More consistent naming of type classes involving orderings (and
  1268 lattices):
  1269 
  1270     lower_semilattice                   ~> semilattice_inf
  1271     upper_semilattice                   ~> semilattice_sup
  1272 
  1273     dense_linear_order                  ~> dense_linorder
  1274 
  1275     pordered_ab_group_add               ~> ordered_ab_group_add
  1276     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  1277     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  1278     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  1279     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  1280     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  1281     pordered_cancel_semiring            ~> ordered_cancel_semiring
  1282     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  1283     pordered_comm_ring                  ~> ordered_comm_ring
  1284     pordered_comm_semiring              ~> ordered_comm_semiring
  1285     pordered_ring                       ~> ordered_ring
  1286     pordered_ring_abs                   ~> ordered_ring_abs
  1287     pordered_semiring                   ~> ordered_semiring
  1288 
  1289     ordered_ab_group_add                ~> linordered_ab_group_add
  1290     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  1291     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  1292     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  1293     ordered_field                       ~> linordered_field
  1294     ordered_field_no_lb                 ~> linordered_field_no_lb
  1295     ordered_field_no_ub                 ~> linordered_field_no_ub
  1296     ordered_field_dense_linear_order    ~> dense_linordered_field
  1297     ordered_idom                        ~> linordered_idom
  1298     ordered_ring                        ~> linordered_ring
  1299     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  1300     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  1301     ordered_ring_strict                 ~> linordered_ring_strict
  1302     ordered_semidom                     ~> linordered_semidom
  1303     ordered_semiring                    ~> linordered_semiring
  1304     ordered_semiring_1                  ~> linordered_semiring_1
  1305     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  1306     ordered_semiring_strict             ~> linordered_semiring_strict
  1307 
  1308   The following slightly odd type classes have been moved to a
  1309   separate theory Library/Lattice_Algebras:
  1310 
  1311     lordered_ab_group_add               ~> lattice_ab_group_add
  1312     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  1313     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  1314     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  1315     lordered_ring                       ~> lattice_ring
  1316 
  1317 INCOMPATIBILITY.
  1318 
  1319 * Refined field classes:
  1320   - classes division_ring_inverse_zero, field_inverse_zero,
  1321     linordered_field_inverse_zero include rule inverse 0 = 0 --
  1322     subsumes former division_by_zero class;
  1323   - numerous lemmas have been ported from field to division_ring.
  1324 INCOMPATIBILITY.
  1325 
  1326 * Refined algebra theorem collections:
  1327   - dropped theorem group group_simps, use algebra_simps instead;
  1328   - dropped theorem group ring_simps, use field_simps instead;
  1329   - proper theorem collection field_simps subsumes former theorem
  1330     groups field_eq_simps and field_simps;
  1331   - dropped lemma eq_minus_self_iff which is a duplicate for
  1332     equal_neg_zero.
  1333 INCOMPATIBILITY.
  1334 
  1335 * Theory Finite_Set and List: some lemmas have been generalized from
  1336 sets to lattices:
  1337 
  1338   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  1339   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  1340   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  1341   union_Union_fold_union        ~> sup_Sup_fold_sup
  1342   Inter_fold_inter              ~> Inf_fold_inf
  1343   Union_fold_union              ~> Sup_fold_sup
  1344   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  1345   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  1346   INTER_fold_inter              ~> INFI_fold_inf
  1347   UNION_fold_union              ~> SUPR_fold_sup
  1348 
  1349 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  1350 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  1351 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  1352 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  1353 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  1354 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  1355 
  1356 * Reorganized theory Multiset: swapped notation of pointwise and
  1357 multiset order:
  1358 
  1359   - pointwise ordering is instance of class order with standard syntax
  1360     <= and <;
  1361   - multiset ordering has syntax <=# and <#; partial order properties
  1362     are provided by means of interpretation with prefix
  1363     multiset_order;
  1364   - less duplication, less historical organization of sections,
  1365     conversion from associations lists to multisets, rudimentary code
  1366     generation;
  1367   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  1368     if needed.
  1369 
  1370 Renamed:
  1371 
  1372   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  1373   multi_count_ext  ~>  multiset_ext
  1374   diff_union_inverse2  ~>  diff_union_cancelR
  1375 
  1376 INCOMPATIBILITY.
  1377 
  1378 * Theory Permutation: replaced local "remove" by List.remove1.
  1379 
  1380 * Code generation: ML and OCaml code is decorated with signatures.
  1381 
  1382 * Theory List: added transpose.
  1383 
  1384 * Library/Nat_Bijection.thy is a collection of bijective functions
  1385 between nat and other types, which supersedes the older libraries
  1386 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  1387 
  1388   Constants:
  1389   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  1390   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  1391   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  1392   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  1393   Countable.pair_encode           ~> prod_encode
  1394   NatIso.prod2nat                 ~> prod_encode
  1395   NatIso.nat2prod                 ~> prod_decode
  1396   NatIso.sum2nat                  ~> sum_encode
  1397   NatIso.nat2sum                  ~> sum_decode
  1398   NatIso.list2nat                 ~> list_encode
  1399   NatIso.nat2list                 ~> list_decode
  1400   NatIso.set2nat                  ~> set_encode
  1401   NatIso.nat2set                  ~> set_decode
  1402 
  1403   Lemmas:
  1404   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  1405   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  1406   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  1407   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  1408   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  1409   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  1410   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  1411   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  1412   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  1413   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  1414   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  1415   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  1416   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  1417 
  1418 * Sledgehammer:
  1419   - Renamed ATP commands:
  1420     atp_info     ~> sledgehammer running_atps
  1421     atp_kill     ~> sledgehammer kill_atps
  1422     atp_messages ~> sledgehammer messages
  1423     atp_minimize ~> sledgehammer minimize
  1424     print_atps   ~> sledgehammer available_atps
  1425     INCOMPATIBILITY.
  1426   - Added user's manual ("isabelle doc sledgehammer").
  1427   - Added option syntax and "sledgehammer_params" to customize
  1428     Sledgehammer's behavior.  See the manual for details.
  1429   - Modified the Isar proof reconstruction code so that it produces
  1430     direct proofs rather than proofs by contradiction.  (This feature
  1431     is still experimental.)
  1432   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  1433     full-typed mode.
  1434   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  1435 
  1436 * Nitpick:
  1437   - Added and implemented "binary_ints" and "bits" options.
  1438   - Added "std" option and implemented support for nonstandard models.
  1439   - Added and implemented "finitize" option to improve the precision
  1440     of infinite datatypes based on a monotonicity analysis.
  1441   - Added support for quotient types.
  1442   - Added support for "specification" and "ax_specification"
  1443     constructs.
  1444   - Added support for local definitions (for "function" and
  1445     "termination" proofs).
  1446   - Added support for term postprocessors.
  1447   - Optimized "Multiset.multiset" and "FinFun.finfun".
  1448   - Improved efficiency of "destroy_constrs" optimization.
  1449   - Fixed soundness bugs related to "destroy_constrs" optimization and
  1450     record getters.
  1451   - Fixed soundness bug related to higher-order constructors.
  1452   - Fixed soundness bug when "full_descrs" is enabled.
  1453   - Improved precision of set constructs.
  1454   - Added "atoms" option.
  1455   - Added cache to speed up repeated Kodkod invocations on the same
  1456     problems.
  1457   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  1458     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  1459     "SAT4J_Light".  INCOMPATIBILITY.
  1460   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  1461     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  1462   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  1463 
  1464 * Method "induct" now takes instantiations of the form t, where t is not
  1465   a variable, as a shorthand for "x == t", where x is a fresh variable.
  1466   If this is not intended, t has to be enclosed in parentheses.
  1467   By default, the equalities generated by definitional instantiations
  1468   are pre-simplified, which may cause parameters of inductive cases
  1469   to disappear, or may even delete some of the inductive cases.
  1470   Use "induct (no_simp)" instead of "induct" to restore the old
  1471   behaviour. The (no_simp) option is also understood by the "cases"
  1472   and "nominal_induct" methods, which now perform pre-simplification, too.
  1473   INCOMPATIBILITY.
  1474 
  1475 
  1476 *** HOLCF ***
  1477 
  1478 * Variable names in lemmas generated by the domain package have
  1479 changed; the naming scheme is now consistent with the HOL datatype
  1480 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  1481 
  1482 * The domain package no longer defines the function "foo_copy" for
  1483 recursive domain "foo".  The reach lemma is now stated directly in
  1484 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  1485 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  1486 
  1487 * Most definedness lemmas generated by the domain package (previously
  1488 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  1489 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  1490 Proofs that used definedness lemmas as intro rules may break,
  1491 potential INCOMPATIBILITY.
  1492 
  1493 * Induction and casedist rules generated by the domain package now
  1494 declare proper case_names (one called "bottom", and one named for each
  1495 constructor).  INCOMPATIBILITY.
  1496 
  1497 * For mutually-recursive domains, separate "reach" and "take_lemma"
  1498 rules are generated for each domain, INCOMPATIBILITY.
  1499 
  1500   foo_bar.reach       ~> foo.reach  bar.reach
  1501   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  1502 
  1503 * Some lemmas generated by the domain package have been renamed for
  1504 consistency with the datatype package, INCOMPATIBILITY.
  1505 
  1506   foo.ind        ~> foo.induct
  1507   foo.finite_ind ~> foo.finite_induct
  1508   foo.coind      ~> foo.coinduct
  1509   foo.casedist   ~> foo.exhaust
  1510   foo.exhaust    ~> foo.nchotomy
  1511 
  1512 * For consistency with other definition packages, the fixrec package
  1513 now generates qualified theorem names, INCOMPATIBILITY.
  1514 
  1515   foo_simps  ~> foo.simps
  1516   foo_unfold ~> foo.unfold
  1517   foo_induct ~> foo.induct
  1518 
  1519 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  1520 method and internal fixrec proofs now use the default simpset instead.
  1521 INCOMPATIBILITY.
  1522 
  1523 * The "contlub" predicate has been removed.  Proof scripts should use
  1524 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  1525 
  1526 * The "admw" predicate has been removed, INCOMPATIBILITY.
  1527 
  1528 * The constants cpair, cfst, and csnd have been removed in favor of
  1529 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  1530 
  1531 
  1532 *** ML ***
  1533 
  1534 * Antiquotations for basic formal entities:
  1535 
  1536     @{class NAME}         -- type class
  1537     @{class_syntax NAME}  -- syntax representation of the above
  1538 
  1539     @{type_name NAME}     -- logical type
  1540     @{type_abbrev NAME}   -- type abbreviation
  1541     @{nonterminal NAME}   -- type of concrete syntactic category
  1542     @{type_syntax NAME}   -- syntax representation of any of the above
  1543 
  1544     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  1545     @{const_abbrev NAME}  -- abbreviated constant
  1546     @{const_syntax NAME}  -- syntax representation of any of the above
  1547 
  1548 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  1549 syntax constant (cf. 'syntax' command).
  1550 
  1551 * Antiquotation @{make_string} inlines a function to print arbitrary
  1552 values similar to the ML toplevel.  The result is compiler dependent
  1553 and may fall back on "?" in certain situations.
  1554 
  1555 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  1556 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  1557 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  1558 not work with the asynchronous Isar document model.
  1559 
  1560 * Configuration options now admit dynamic default values, depending on
  1561 the context or even global references.
  1562 
  1563 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  1564 uses an efficient external library if available (for Poly/ML).
  1565 
  1566 * Renamed some important ML structures, while keeping the old names
  1567 for some time as aliases within the structure Legacy:
  1568 
  1569   OuterKeyword  ~>  Keyword
  1570   OuterLex      ~>  Token
  1571   OuterParse    ~>  Parse
  1572   OuterSyntax   ~>  Outer_Syntax
  1573   PrintMode     ~>  Print_Mode
  1574   SpecParse     ~>  Parse_Spec
  1575   ThyInfo       ~>  Thy_Info
  1576   ThyLoad       ~>  Thy_Load
  1577   ThyOutput     ~>  Thy_Output
  1578   TypeInfer     ~>  Type_Infer
  1579 
  1580 Note that "open Legacy" simplifies porting of sources, but forgetting
  1581 to remove it again will complicate porting again in the future.
  1582 
  1583 * Most operations that refer to a global context are named
  1584 accordingly, e.g. Simplifier.global_context or
  1585 ProofContext.init_global.  There are some situations where a global
  1586 context actually works, but under normal circumstances one needs to
  1587 pass the proper local context through the code!
  1588 
  1589 * Discontinued old TheoryDataFun with its copy/init operation -- data
  1590 needs to be pure.  Functor Theory_Data_PP retains the traditional
  1591 Pretty.pp argument to merge, which is absent in the standard
  1592 Theory_Data version.
  1593 
  1594 * Sorts.certify_sort and derived "cert" operations for types and terms
  1595 no longer minimize sorts.  Thus certification at the boundary of the
  1596 inference kernel becomes invariant under addition of class relations,
  1597 which is an important monotonicity principle.  Sorts are now minimized
  1598 in the syntax layer only, at the boundary between the end-user and the
  1599 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  1600 explicitly in rare situations.
  1601 
  1602 * Renamed old-style Drule.standard to Drule.export_without_context, to
  1603 emphasize that this is in no way a standard operation.
  1604 INCOMPATIBILITY.
  1605 
  1606 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  1607 usual for resolution.  Rare INCOMPATIBILITY.
  1608 
  1609 * Renamed varify/unvarify operations to varify_global/unvarify_global
  1610 to emphasize that these only work in a global situation (which is
  1611 quite rare).
  1612 
  1613 * Curried take and drop in library.ML; negative length is interpreted
  1614 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  1615 
  1616 * Proof terms: type substitutions on proof constants now use canonical
  1617 order of type variables.  INCOMPATIBILITY for tools working with proof
  1618 terms.
  1619 
  1620 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  1621 may no longer carry premises.  User-level specifications are
  1622 transformed accordingly by Thm.add_axiom/add_def.
  1623 
  1624 
  1625 *** System ***
  1626 
  1627 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  1628 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  1629 proof terms are enabled unconditionally in the new HOL-Proofs image.
  1630 
  1631 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  1632 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  1633 respectively.
  1634 
  1635 * Old lib/scripts/polyml-platform is superseded by the
  1636 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  1637 variant, even on a 64 bit machine.  The following example setting
  1638 prefers 64 bit if available:
  1639 
  1640   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  1641 
  1642 * The preliminary Isabelle/jEdit application demonstrates the emerging
  1643 Isabelle/Scala layer for advanced prover interaction and integration.
  1644 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  1645 component.
  1646 
  1647 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  1648 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  1649 similar to the default assignment of the document preparation system
  1650 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  1651 provides some operations for direct access to the font without asking
  1652 the user for manual installation.
  1653 
  1654 
  1655 
  1656 New in Isabelle2009-1 (December 2009)
  1657 -------------------------------------
  1658 
  1659 *** General ***
  1660 
  1661 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  1662 one backslash should be used, even in ML sources.
  1663 
  1664 
  1665 *** Pure ***
  1666 
  1667 * Locale interpretation propagates mixins along the locale hierarchy.
  1668 The currently only available mixins are the equations used to map
  1669 local definitions to terms of the target domain of an interpretation.
  1670 
  1671 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  1672 loc" to print all interpretations of locale "loc" in the theory.
  1673 Interpretations in proofs are not shown.
  1674 
  1675 * Thoroughly revised locales tutorial.  New section on conditional
  1676 interpretation.
  1677 
  1678 * On instantiation of classes, remaining undefined class parameters
  1679 are formally declared.  INCOMPATIBILITY.
  1680 
  1681 
  1682 *** Document preparation ***
  1683 
  1684 * New generalized style concept for printing terms: @{foo (style) ...}
  1685 instead of @{foo_style style ...}  (old form is still retained for
  1686 backward compatibility).  Styles can be also applied for
  1687 antiquotations prop, term_type and typeof.
  1688 
  1689 
  1690 *** HOL ***
  1691 
  1692 * New proof method "smt" for a combination of first-order logic with
  1693 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  1694 fixed-size bitvectors; there is also basic support for higher-order
  1695 features (esp. lambda abstractions).  It is an incomplete decision
  1696 procedure based on external SMT solvers using the oracle mechanism;
  1697 for the SMT solver Z3, this method is proof-producing.  Certificates
  1698 are provided to avoid calling the external solvers solely for
  1699 re-checking proofs.  Due to a remote SMT service there is no need for
  1700 installing SMT solvers locally.  See src/HOL/SMT.
  1701 
  1702 * New commands to load and prove verification conditions generated by
  1703 the Boogie program verifier or derived systems (e.g. the Verifying C
  1704 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1705 
  1706 * New counterexample generator tool 'nitpick' based on the Kodkod
  1707 relational model finder.  See src/HOL/Tools/Nitpick and
  1708 src/HOL/Nitpick_Examples.
  1709 
  1710 * New commands 'code_pred' and 'values' to invoke the predicate
  1711 compiler and to enumerate values of inductive predicates.
  1712 
  1713 * A tabled implementation of the reflexive transitive closure.
  1714 
  1715 * New implementation of quickcheck uses generic code generator;
  1716 default generators are provided for all suitable HOL types, records
  1717 and datatypes.  Old quickcheck can be re-activated importing theory
  1718 Library/SML_Quickcheck.
  1719 
  1720 * New testing tool Mirabelle for automated proof tools.  Applies
  1721 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1722 every proof step in a theory.  To be used in batch mode via the
  1723 "mirabelle" utility.
  1724 
  1725 * New proof method "sos" (sum of squares) for nonlinear real
  1726 arithmetic (originally due to John Harison). It requires theory
  1727 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1728 works well in practice on quantifier-free real arithmetic with +, -,
  1729 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1730 inequalities between polynomials.  It makes use of external
  1731 semidefinite programming solvers.  Method "sos" generates a
  1732 certificate that can be pasted into the proof thus avoiding the need
  1733 to call an external tool every time the proof is checked.  See
  1734 src/HOL/Library/Sum_Of_Squares.
  1735 
  1736 * New method "linarith" invokes existing linear arithmetic decision
  1737 procedure only.
  1738 
  1739 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1740 
  1741 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1742 Causes full type information to be output to the ATPs.  This slows
  1743 ATPs down considerably but eliminates a source of unsound "proofs"
  1744 that fail later.
  1745 
  1746 * New method "metisFT": A version of metis that uses full type
  1747 information in order to avoid failures of proof reconstruction.
  1748 
  1749 * New evaluator "approximate" approximates an real valued term using
  1750 the same method as the approximation method.
  1751 
  1752 * Method "approximate" now supports arithmetic expressions as
  1753 boundaries of intervals and implements interval splitting and Taylor
  1754 series expansion.
  1755 
  1756 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1757 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1758 
  1759 * New theory SupInf of the supremum and infimum operators for sets of
  1760 reals.
  1761 
  1762 * New theory Probability, which contains a development of measure
  1763 theory, eventually leading to Lebesgue integration and probability.
  1764 
  1765 * Extended Multivariate Analysis to include derivation and Brouwer's
  1766 fixpoint theorem.
  1767 
  1768 * Reorganization of number theory, INCOMPATIBILITY:
  1769   - new number theory development for nat and int, in theories Divides
  1770     and GCD as well as in new session Number_Theory
  1771   - some constants and facts now suffixed with _nat and _int
  1772     accordingly
  1773   - former session NumberTheory now named Old_Number_Theory, including
  1774     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1775   - moved theory Pocklington from src/HOL/Library to
  1776     src/HOL/Old_Number_Theory
  1777 
  1778 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1779 lcm of finite and infinite sets. It is shown that they form a complete
  1780 lattice.
  1781 
  1782 * Class semiring_div requires superclass no_zero_divisors and proof of
  1783 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1784 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1785 generalized to class semiring_div, subsuming former theorems
  1786 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1787 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1788 INCOMPATIBILITY.
  1789 
  1790 * Refinements to lattice classes and sets:
  1791   - less default intro/elim rules in locale variant, more default
  1792     intro/elim rules in class variant: more uniformity
  1793   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1794     le_inf_iff
  1795   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1796     sup_aci)
  1797   - renamed ACI to inf_sup_aci
  1798   - new class "boolean_algebra"
  1799   - class "complete_lattice" moved to separate theory
  1800     "Complete_Lattice"; corresponding constants (and abbreviations)
  1801     renamed and with authentic syntax:
  1802     Set.Inf ~>    Complete_Lattice.Inf
  1803     Set.Sup ~>    Complete_Lattice.Sup
  1804     Set.INFI ~>   Complete_Lattice.INFI
  1805     Set.SUPR ~>   Complete_Lattice.SUPR
  1806     Set.Inter ~>  Complete_Lattice.Inter
  1807     Set.Union ~>  Complete_Lattice.Union
  1808     Set.INTER ~>  Complete_Lattice.INTER
  1809     Set.UNION ~>  Complete_Lattice.UNION
  1810   - authentic syntax for
  1811     Set.Pow
  1812     Set.image
  1813   - mere abbreviations:
  1814     Set.empty               (for bot)
  1815     Set.UNIV                (for top)
  1816     Set.inter               (for inf, formerly Set.Int)
  1817     Set.union               (for sup, formerly Set.Un)
  1818     Complete_Lattice.Inter  (for Inf)
  1819     Complete_Lattice.Union  (for Sup)
  1820     Complete_Lattice.INTER  (for INFI)
  1821     Complete_Lattice.UNION  (for SUPR)
  1822   - object-logic definitions as far as appropriate
  1823 
  1824 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1825 Un_subset_iff are explicitly deleted as default simp rules; then also
  1826 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1827 deleted to achieve the desired effect.
  1828 
  1829 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1830 rules by default any longer; the same applies to min_max.inf_absorb1
  1831 etc.  INCOMPATIBILITY.
  1832 
  1833 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1834 pred_set_conv by default.  INCOMPATIBILITY.
  1835 
  1836 * Power operations on relations and functions are now one dedicated
  1837 constant "compow" with infix syntax "^^".  Power operation on
  1838 multiplicative monoids retains syntax "^" and is now defined generic
  1839 in class power.  INCOMPATIBILITY.
  1840 
  1841 * Relation composition "R O S" now has a more standard argument order:
  1842 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1843 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1844 break, since the O_assoc rule was not rewritten like this.  Fix using
  1845 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1846 
  1847 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1848 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1849 INCOMPATIBILITY.
  1850 
  1851 * Most rules produced by inductive and datatype package have mandatory
  1852 prefixes.  INCOMPATIBILITY.
  1853 
  1854 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1855 the attribute of the same name.  Each of the theorems in the list
  1856 DERIV_intros assumes composition with an additional function and
  1857 matches a variable to the derivative, which has to be solved by the
  1858 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1859 of most elementary terms.  Former Maclauren.DERIV_tac and
  1860 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1861 INCOMPATIBILITY.
  1862 
  1863 * Code generator attributes follow the usual underscore convention:
  1864     code_unfold     replaces    code unfold
  1865     code_post       replaces    code post
  1866     etc.
  1867   INCOMPATIBILITY.
  1868 
  1869 * Renamed methods:
  1870     sizechange -> size_change
  1871     induct_scheme -> induction_schema
  1872   INCOMPATIBILITY.
  1873 
  1874 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1875 INCOMPATIBILITY, use "undefined" directly.
  1876 
  1877 * Renamed theorems:
  1878     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1879     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1880     Suc_plus1 -> Suc_eq_plus1
  1881     *anti_sym -> *antisym*
  1882     vector_less_eq_def -> vector_le_def
  1883   INCOMPATIBILITY.
  1884 
  1885 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1886 INCOMPATIBILITY.
  1887 
  1888 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1889 INCOMPATIBILITY.
  1890 
  1891 
  1892 *** HOLCF ***
  1893 
  1894 * Theory Representable defines a class "rep" of domains that are
  1895 representable (via an ep-pair) in the universal domain type "udom".
  1896 Instances are provided for all type constructors defined in HOLCF.
  1897 
  1898 * The 'new_domain' command is a purely definitional version of the
  1899 domain package, for representable domains.  Syntax is identical to the
  1900 old domain package.  The 'new_domain' package also supports indirect
  1901 recursion using previously-defined type constructors.  See
  1902 src/HOLCF/ex/New_Domain.thy for examples.
  1903 
  1904 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1905 on the left-hand side of an equation, and then performs
  1906 simplification.  Rewriting is done using rules declared with the
  1907 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1908 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1909 
  1910 * The pattern-match compiler in 'fixrec' can now handle constructors
  1911 with HOL function types.  Pattern-match combinators for the Pair
  1912 constructor are pre-configured.
  1913 
  1914 * The 'fixrec' package now produces better fixed-point induction rules
  1915 for mutually-recursive definitions:  Induction rules have conclusions
  1916 of the form "P foo bar" instead of "P <foo, bar>".
  1917 
  1918 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1919 been renamed to "below".  The name "below" now replaces "less" in many
  1920 theorem names.  (Legacy theorem names using "less" are still supported
  1921 as well.)
  1922 
  1923 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1924 patterns can be used to generate strictness rules, or to make
  1925 functions more strict (much like the bang-patterns supported by the
  1926 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1927 examples.
  1928 
  1929 
  1930 *** ML ***
  1931 
  1932 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1933 errors and run-time exceptions, including detailed source positions.
  1934 
  1935 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1936 identified entries, with some additional information such as source
  1937 position, logical grouping etc.
  1938 
  1939 * Theory and context data is now introduced by the simplified and
  1940 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1941 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1942 copy operation) is still available for some time.
  1943 
  1944 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1945 provides a high-level programming interface to synchronized state
  1946 variables with atomic update.  This works via pure function
  1947 application within a critical section -- its runtime should be as
  1948 short as possible; beware of deadlocks if critical code is nested,
  1949 either directly or indirectly via other synchronized variables!
  1950 
  1951 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1952 wraps raw ML references, explicitly indicating their non-thread-safe
  1953 behaviour.  The Isar toplevel keeps this structure open, to
  1954 accommodate Proof General as well as quick and dirty interactive
  1955 experiments with references.
  1956 
  1957 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1958 parallel tactical reasoning.
  1959 
  1960 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1961 are similar to SUBPROOF, but are slightly more flexible: only the
  1962 specified parts of the subgoal are imported into the context, and the
  1963 body tactic may introduce new subgoals and schematic variables.
  1964 
  1965 * Old tactical METAHYPS, which does not observe the proof context, has
  1966 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1967 or Subgoal.FOCUS etc.
  1968 
  1969 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  1970 functors have their own ML name space there is no point to mark them
  1971 separately.)  Minor INCOMPATIBILITY.
  1972 
  1973 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  1974 
  1975 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  1976 INCOMPATIBILITY.
  1977 
  1978 * Operations of structure Skip_Proof no longer require quick_and_dirty
  1979 mode, which avoids critical setmp.
  1980 
  1981 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  1982 combinators for "args".  INCOMPATIBILITY, need to use simplified
  1983 Attrib/Method.setup introduced in Isabelle2009.
  1984 
  1985 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  1986 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  1987 last resort.  INCOMPATIBILITY.
  1988 
  1989 * Display.pretty_thm now requires a proper context (cf. former
  1990 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  1991 or even Display.pretty_thm_without_context as last resort.
  1992 INCOMPATIBILITY.
  1993 
  1994 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  1995 Syntax.pretty_typ/term directly, preferably with proper context
  1996 instead of global theory.
  1997 
  1998 
  1999 *** System ***
  2000 
  2001 * Further fine tuning of parallel proof checking, scales up to 8 cores
  2002 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  2003 usedir option -q.
  2004 
  2005 * Support for additional "Isabelle components" via etc/components, see
  2006 also the system manual.
  2007 
  2008 * The isabelle makeall tool now operates on all components with
  2009 IsaMakefile, not just hardwired "logics".
  2010 
  2011 * Removed "compress" option from isabelle-process and isabelle usedir;
  2012 this is always enabled.
  2013 
  2014 * Discontinued support for Poly/ML 4.x versions.
  2015 
  2016 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  2017 on a given logic image.  This requires the lighttpd webserver and is
  2018 currently supported on Linux only.
  2019 
  2020 
  2021 
  2022 New in Isabelle2009 (April 2009)
  2023 --------------------------------
  2024 
  2025 *** General ***
  2026 
  2027 * Simplified main Isabelle executables, with less surprises on
  2028 case-insensitive file-systems (such as Mac OS).
  2029 
  2030   - The main Isabelle tool wrapper is now called "isabelle" instead of
  2031     "isatool."
  2032 
  2033   - The former "isabelle" alias for "isabelle-process" has been
  2034     removed (should rarely occur to regular users).
  2035 
  2036   - The former "isabelle-interface" and its alias "Isabelle" have been
  2037     removed (interfaces are now regular Isabelle tools).
  2038 
  2039 Within scripts and make files, the Isabelle environment variables
  2040 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  2041 respectively.  (The latter are still available as legacy feature.)
  2042 
  2043 The old isabelle-interface wrapper could react in confusing ways if
  2044 the interface was uninstalled or changed otherwise.  Individual
  2045 interface tool configuration is now more explicit, see also the
  2046 Isabelle system manual.  In particular, Proof General is now available
  2047 via "isabelle emacs".
  2048 
  2049 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  2050 purge installed copies of Isabelle executables and re-run "isabelle
  2051 install -p ...", or use symlinks.
  2052 
  2053 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  2054 old ~/isabelle, which was slightly non-standard and apt to cause
  2055 surprises on case-insensitive file-systems (such as Mac OS).
  2056 
  2057 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  2058 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  2059 care is required when using older releases of Isabelle.  Note that
  2060 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  2061 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  2062 
  2063 * Proofs of fully specified statements are run in parallel on
  2064 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  2065 a regular 4-core machine, if the initial heap space is made reasonably
  2066 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  2067 
  2068 * The main reference manuals ("isar-ref", "implementation", and
  2069 "system") have been updated and extended.  Formally checked references
  2070 as hyperlinks are now available uniformly.
  2071 
  2072 
  2073 *** Pure ***
  2074 
  2075 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  2076 respects.  The most important changes are listed below.  See the
  2077 Tutorial on Locales ("locales" manual) for details.
  2078 
  2079 - In locale expressions, instantiation replaces renaming.  Parameters
  2080 must be declared in a for clause.  To aid compatibility with previous
  2081 parameter inheritance, in locale declarations, parameters that are not
  2082 'touched' (instantiation position "_" or omitted) are implicitly added
  2083 with their syntax at the beginning of the for clause.
  2084 
  2085 - Syntax from abbreviations and definitions in locales is available in
  2086 locale expressions and context elements.  The latter is particularly
  2087 useful in locale declarations.
  2088 
  2089 - More flexible mechanisms to qualify names generated by locale
  2090 expressions.  Qualifiers (prefixes) may be specified in locale
  2091 expressions, and can be marked as mandatory (syntax: "name!:") or
  2092 optional (syntax "name?:").  The default depends for plain "name:"
  2093 depends on the situation where a locale expression is used: in
  2094 commands 'locale' and 'sublocale' prefixes are optional, in
  2095 'interpretation' and 'interpret' prefixes are mandatory.  The old
  2096 implicit qualifiers derived from the parameter names of a locale are
  2097 no longer generated.
  2098 
  2099 - Command "sublocale l < e" replaces "interpretation l < e".  The
  2100 instantiation clause in "interpretation" and "interpret" (square
  2101 brackets) is no longer available.  Use locale expressions.
  2102 
  2103 - When converting proof scripts, mandatory qualifiers in
  2104 'interpretation' and 'interpret' should be retained by default, even
  2105 if this is an INCOMPATIBILITY compared to former behavior.  In the
  2106 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  2107 in locale expressions range over a single locale instance only.
  2108 
  2109 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  2110 In existing theorem specifications replace the includes element by the
  2111 respective context elements of the included locale, omitting those
  2112 that are already present in the theorem specification.  Multiple
  2113 assume elements of a locale should be replaced by a single one
  2114 involving the locale predicate.  In the proof body, declarations (most
  2115 notably theorems) may be regained by interpreting the respective
  2116 locales in the proof context as required (command "interpret").
  2117 
  2118 If using "includes" in replacement of a target solely because the
  2119 parameter types in the theorem are not as general as in the target,
  2120 consider declaring a new locale with additional type constraints on
  2121 the parameters (context element "constrains").
  2122 
  2123 - Discontinued "locale (open)".  INCOMPATIBILITY.
  2124 
  2125 - Locale interpretation commands no longer attempt to simplify goal.
  2126 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  2127 methods intro_locales and unfold_locales to clarify.
  2128 
  2129 - Locale interpretation commands no longer accept interpretation
  2130 attributes.  INCOMPATIBILITY.
  2131 
  2132 * Class declaration: so-called "base sort" must not be given in import
  2133 list any longer, but is inferred from the specification.  Particularly
  2134 in HOL, write
  2135 
  2136     class foo = ...
  2137 
  2138 instead of
  2139 
  2140     class foo = type + ...
  2141 
  2142 * Class target: global versions of theorems stemming do not carry a
  2143 parameter prefix any longer.  INCOMPATIBILITY.
  2144 
  2145 * Class 'instance' command no longer accepts attached definitions.
  2146 INCOMPATIBILITY, use proper 'instantiation' target instead.
  2147 
  2148 * Recovered hiding of consts, which was accidentally broken in
  2149 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  2150 makes c inaccessible; consider using ``hide (open) const c'' instead.
  2151 
  2152 * Slightly more coherent Pure syntax, with updated documentation in
  2153 isar-ref manual.  Removed locales meta_term_syntax and
  2154 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  2155 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  2156 directly in regular applications.
  2157 
  2158 * There is a new syntactic category "float_const" for signed decimal
  2159 fractions (e.g. 123.45 or -123.45).
  2160 
  2161 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  2162 interface with 'setup' command instead.
  2163 
  2164 * Command 'local_setup' is similar to 'setup', but operates on a local
  2165 theory context.
  2166 
  2167 * The 'axiomatization' command now only works within a global theory
  2168 context.  INCOMPATIBILITY.
  2169 
  2170 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  2171 hypotheses.  Sorts required in the course of reasoning need to be
  2172 covered by the constraints in the initial statement, completed by the
  2173 type instance information of the background theory.  Non-trivial sort
  2174 hypotheses, which rarely occur in practice, may be specified via
  2175 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  2176 
  2177   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  2178 
  2179 The result contains an implicit sort hypotheses as before --
  2180 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  2181 normalization.
  2182 
  2183 * Generalized Isar history, with support for linear undo, direct state
  2184 addressing etc.
  2185 
  2186 * Changed defaults for unify configuration options:
  2187 
  2188   unify_trace_bound = 50 (formerly 25)
  2189   unify_search_bound = 60 (formerly 30)
  2190 
  2191 * Different bookkeeping for code equations (INCOMPATIBILITY):
  2192 
  2193   a) On theory merge, the last set of code equations for a particular
  2194      constant is taken (in accordance with the policy applied by other
  2195      parts of the code generator framework).
  2196 
  2197   b) Code equations stemming from explicit declarations (e.g. code
  2198      attribute) gain priority over default code equations stemming
  2199      from definition, primrec, fun etc.
  2200 
  2201 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  2202 
  2203 * Unified theorem tables for both code generators.  Thus [code
  2204 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  2205 
  2206 * Command 'find_consts' searches for constants based on type and name
  2207 patterns, e.g.
  2208 
  2209     find_consts "_ => bool"
  2210 
  2211 By default, matching is against subtypes, but it may be restricted to
  2212 the whole type.  Searching by name is possible.  Multiple queries are
  2213 conjunctive and queries may be negated by prefixing them with a
  2214 hyphen:
  2215 
  2216     find_consts strict: "_ => bool" name: "Int" -"int => int"
  2217 
  2218 * New 'find_theorems' criterion "solves" matches theorems that
  2219 directly solve the current goal (modulo higher-order unification).
  2220 
  2221 * Auto solve feature for main theorem statements: whenever a new goal
  2222 is stated, "find_theorems solves" is called; any theorems that could
  2223 solve the lemma directly are listed as part of the goal state.
  2224 Cf. associated options in Proof General Isabelle settings menu,
  2225 enabled by default, with reasonable timeout for pathological cases of
  2226 higher-order unification.
  2227 
  2228 
  2229 *** Document preparation ***
  2230 
  2231 * Antiquotation @{lemma} now imitates a regular terminal proof,
  2232 demanding keyword 'by' and supporting the full method expression
  2233 syntax just like the Isar command 'by'.
  2234 
  2235 
  2236 *** HOL ***
  2237 
  2238 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  2239 points Main and Complex_Main remain as before.
  2240 
  2241 * Logic image HOL-Plain provides a minimal HOL with the most important
  2242 tools available (inductive, datatype, primrec, ...).  This facilitates
  2243 experimentation and tool development.  Note that user applications
  2244 (and library theories) should never refer to anything below theory
  2245 Main, as before.
  2246 
  2247 * Logic image HOL-Main stops at theory Main, and thus facilitates
  2248 experimentation due to shorter build times.
  2249 
  2250 * Logic image HOL-NSA contains theories of nonstandard analysis which
  2251 were previously part of former HOL-Complex.  Entry point Hyperreal
  2252 remains valid, but theories formerly using Complex_Main should now use
  2253 new entry point Hypercomplex.
  2254 
  2255 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  2256 Posix processes.  Avoids potentially expensive forking of the ML
  2257 process.  New thread-based implementation also works on non-Unix
  2258 platforms (Cygwin).  Provers are no longer hardwired, but defined
  2259 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  2260 commands are covered in the isar-ref manual.
  2261 
  2262 * Wrapper scripts for remote SystemOnTPTP service allows to use
  2263 sledgehammer without local ATP installation (Vampire etc.). Other
  2264 provers may be included via suitable ML wrappers, see also
  2265 src/HOL/ATP_Linkup.thy.
  2266 
  2267 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  2268 menu.
  2269 
  2270 * The metis method no longer fails because the theorem is too trivial
  2271 (contains the empty clause).
  2272 
  2273 * The metis method now fails in the usual manner, rather than raising
  2274 an exception, if it determines that it cannot prove the theorem.
  2275 
  2276 * Method "coherent" implements a prover for coherent logic (see also
  2277 src/Tools/coherent.ML).
  2278 
  2279 * Constants "undefined" and "default" replace "arbitrary".  Usually
  2280 "undefined" is the right choice to replace "arbitrary", though
  2281 logically there is no difference.  INCOMPATIBILITY.
  2282 
  2283 * Command "value" now integrates different evaluation mechanisms.  The
  2284 result of the first successful evaluation mechanism is printed.  In
  2285 square brackets a particular named evaluation mechanisms may be
  2286 specified (currently, [SML], [code] or [nbe]).  See further
  2287 src/HOL/ex/Eval_Examples.thy.
  2288 
  2289 * Normalization by evaluation now allows non-leftlinear equations.
  2290 Declare with attribute [code nbe].
  2291 
  2292 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  2293 as the structured Isar versions "cases" and "induct", cf. the
  2294 corresponding "cases" and "induct" attributes.  Mutual induction rules
  2295 are now presented as a list of individual projections
  2296 (e.g. foo_bar.inducts for types foo and bar); the old format with
  2297 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  2298 rare situations a different rule is selected --- notably nested tuple
  2299 elimination instead of former prod.exhaust: use explicit (case_tac t
  2300 rule: prod.exhaust) here.
  2301 
  2302 * Attributes "cases", "induct", "coinduct" support "del" option.
  2303 
  2304 * Removed fact "case_split_thm", which duplicates "case_split".
  2305 
  2306 * The option datatype has been moved to a new theory Option.  Renamed
  2307 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  2308 
  2309 * New predicate "strict_mono" classifies strict functions on partial
  2310 orders.  With strict functions on linear orders, reasoning about
  2311 (in)equalities is facilitated by theorems "strict_mono_eq",
  2312 "strict_mono_less_eq" and "strict_mono_less".
  2313 
  2314 * Some set operations are now proper qualified constants with
  2315 authentic syntax.  INCOMPATIBILITY:
  2316 
  2317     op Int ~>   Set.Int
  2318     op Un ~>    Set.Un
  2319     INTER ~>    Set.INTER
  2320     UNION ~>    Set.UNION
  2321     Inter ~>    Set.Inter
  2322     Union ~>    Set.Union
  2323     {} ~>       Set.empty
  2324     UNIV ~>     Set.UNIV
  2325 
  2326 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  2327 theory Set.
  2328 
  2329 * Auxiliary class "itself" has disappeared -- classes without any
  2330 parameter are treated as expected by the 'class' command.
  2331 
  2332 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  2333 
  2334 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  2335 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  2336 
  2337 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  2338 method "approximation".  It proves formulas on real values by using
  2339 interval arithmetic.  In the formulas are also the transcendental
  2340 functions sin, cos, tan, atan, ln, exp and the constant pi are
  2341 allowed. For examples see
  2342 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  2343 
  2344 * Theory "Reflection" now resides in HOL/Library.
  2345 
  2346 * Entry point to Word library now simply named "Word".
  2347 INCOMPATIBILITY.
  2348 
  2349 * Made source layout more coherent with logical distribution
  2350 structure:
  2351 
  2352     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  2353     src/HOL/Library/Code_Message.thy ~> src/HOL/
  2354     src/HOL/Library/GCD.thy ~> src/HOL/
  2355     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  2356     src/HOL/Library/Parity.thy ~> src/HOL/
  2357     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  2358     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  2359     src/HOL/Real/Lubs.thy ~> src/HOL/
  2360     src/HOL/Real/PReal.thy ~> src/HOL/
  2361     src/HOL/Real/Rational.thy ~> src/HOL/
  2362     src/HOL/Real/RComplete.thy ~> src/HOL/
  2363     src/HOL/Real/RealDef.thy ~> src/HOL/
  2364     src/HOL/Real/RealPow.thy ~> src/HOL/
  2365     src/HOL/Real/Real.thy ~> src/HOL/
  2366     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  2367     src/HOL/Complex/Complex.thy ~> src/HOL/
  2368     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  2369     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  2370     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  2371     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  2372     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  2373     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  2374     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  2375     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  2376     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  2377     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  2378     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  2379     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  2380     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  2381     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  2382     src/HOL/Real/Float ~> src/HOL/Library/
  2383     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  2384     src/HOL/Real/RealVector.thy ~> src/HOL/
  2385 
  2386     src/HOL/arith_data.ML ~> src/HOL/Tools
  2387     src/HOL/hologic.ML ~> src/HOL/Tools
  2388     src/HOL/simpdata.ML ~> src/HOL/Tools
  2389     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  2390     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  2391     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  2392     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  2393     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  2394     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  2395     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  2396 
  2397     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  2398     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  2399     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  2400     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  2401     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  2402     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  2403 
  2404 * If methods "eval" and "evaluation" encounter a structured proof
  2405 state with !!/==>, only the conclusion is evaluated to True (if
  2406 possible), avoiding strange error messages.
  2407 
  2408 * Method "sizechange" automates termination proofs using (a
  2409 modification of) the size-change principle.  Requires SAT solver.  See
  2410 src/HOL/ex/Termination.thy for examples.
  2411 
  2412 * Simplifier: simproc for let expressions now unfolds if bound
  2413 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  2414 
  2415 * Method "arith": Linear arithmetic now ignores all inequalities when
  2416 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  2417 
  2418 * New attribute "arith" for facts that should always be used
  2419 automatically by arithmetic. It is intended to be used locally in
  2420 proofs, e.g.
  2421 
  2422   assumes [arith]: "x > 0"
  2423 
  2424 Global usage is discouraged because of possible performance impact.
  2425 
  2426 * New classes "top" and "bot" with corresponding operations "top" and
  2427 "bot" in theory Orderings; instantiation of class "complete_lattice"
  2428 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  2429 
  2430 * Changed definition lemma "less_fun_def" in order to provide an
  2431 instance for preorders on functions; use lemma "less_le" instead.
  2432 INCOMPATIBILITY.
  2433 
  2434 * Theory Orderings: class "wellorder" moved here, with explicit
  2435 induction rule "less_induct" as assumption.  For instantiation of
  2436 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  2437 INCOMPATIBILITY.
  2438 
  2439 * Theory Orderings: added class "preorder" as superclass of "order".
  2440 INCOMPATIBILITY: Instantiation proofs for order, linorder
  2441 etc. slightly changed.  Some theorems named order_class.* now named
  2442 preorder_class.*.
  2443 
  2444 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  2445 "diag" to "Id_on".
  2446 
  2447 * Theory Finite_Set: added a new fold combinator of type
  2448 
  2449   ('a => 'b => 'b) => 'b => 'a set => 'b
  2450 
  2451 Occasionally this is more convenient than the old fold combinator
  2452 which is now defined in terms of the new one and renamed to
  2453 fold_image.
  2454 
  2455 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  2456 and "ring_simps" have been replaced by "algebra_simps" (which can be
  2457 extended with further lemmas!).  At the moment both still exist but
  2458 the former will disappear at some point.
  2459 
  2460 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  2461 class recpower.  Type-specific simp rules for various recpower types
  2462 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  2463 
  2464 rat_power_0    -> power_0
  2465 rat_power_Suc  -> power_Suc
  2466 realpow_0      -> power_0
  2467 realpow_Suc    -> power_Suc
  2468 complexpow_0   -> power_0
  2469 complexpow_Suc -> power_Suc
  2470 power_poly_0   -> power_0
  2471 power_poly_Suc -> power_Suc
  2472 
  2473 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  2474 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  2475 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  2476 of lemmas from Divides has been generalized from nat to class
  2477 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  2478 renames resulting from duplicate elimination:
  2479 
  2480     dvd_def_mod ~>          dvd_eq_mod_eq_0
  2481     zero_dvd_iff ~>         dvd_0_left_iff
  2482     dvd_0 ~>                dvd_0_right
  2483     DIVISION_BY_ZERO_DIV ~> div_by_0
  2484     DIVISION_BY_ZERO_MOD ~> mod_by_0
  2485     mult_div ~>             div_mult_self2_is_id
  2486     mult_mod ~>             mod_mult_self2_is_0
  2487 
  2488 * Theory IntDiv: removed many lemmas that are instances of class-based
  2489 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  2490 rename old lemmas as follows:
  2491 
  2492 dvd_diff               -> nat_dvd_diff
  2493 dvd_zminus_iff         -> dvd_minus_iff
  2494 mod_add1_eq            -> mod_add_eq
  2495 mod_mult1_eq           -> mod_mult_right_eq
  2496 mod_mult1_eq'          -> mod_mult_left_eq
  2497 mod_mult_distrib_mod   -> mod_mult_eq
  2498 nat_mod_add_left_eq    -> mod_add_left_eq
  2499 nat_mod_add_right_eq   -> mod_add_right_eq
  2500 nat_mod_div_trivial    -> mod_div_trivial
  2501 nat_mod_mod_trivial    -> mod_mod_trivial
  2502 zdiv_zadd_self1        -> div_add_self1
  2503 zdiv_zadd_self2        -> div_add_self2
  2504 zdiv_zmult_self1       -> div_mult_self2_is_id
  2505 zdiv_zmult_self2       -> div_mult_self1_is_id
  2506 zdvd_triv_left         -> dvd_triv_left
  2507 zdvd_triv_right        -> dvd_triv_right
  2508 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  2509 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  2510 zmod_zadd_left_eq      -> mod_add_left_eq
  2511 zmod_zadd_right_eq     -> mod_add_right_eq
  2512 zmod_zadd_self1        -> mod_add_self1
  2513 zmod_zadd_self2        -> mod_add_self2
  2514 zmod_zadd1_eq          -> mod_add_eq
  2515 zmod_zdiff1_eq         -> mod_diff_eq
  2516 zmod_zdvd_zmod         -> mod_mod_cancel
  2517 zmod_zmod_cancel       -> mod_mod_cancel
  2518 zmod_zmult_self1       -> mod_mult_self2_is_0
  2519 zmod_zmult_self2       -> mod_mult_self1_is_0
  2520 zmod_1                 -> mod_by_1
  2521 zdiv_1                 -> div_by_1
  2522 zdvd_abs1              -> abs_dvd_iff
  2523 zdvd_abs2              -> dvd_abs_iff
  2524 zdvd_refl              -> dvd_refl
  2525 zdvd_trans             -> dvd_trans
  2526 zdvd_zadd              -> dvd_add
  2527 zdvd_zdiff             -> dvd_diff
  2528 zdvd_zminus_iff        -> dvd_minus_iff
  2529 zdvd_zminus2_iff       -> minus_dvd_iff
  2530 zdvd_zmultD            -> dvd_mult_right
  2531 zdvd_zmultD2           -> dvd_mult_left
  2532 zdvd_zmult_mono        -> mult_dvd_mono
  2533 zdvd_0_right           -> dvd_0_right
  2534 zdvd_0_left            -> dvd_0_left_iff
  2535 zdvd_1_left            -> one_dvd
  2536 zminus_dvd_iff         -> minus_dvd_iff
  2537 
  2538 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  2539 
  2540 * The real numbers offer decimal input syntax: 12.34 is translated
  2541 into 1234/10^2. This translation is not reversed upon output.
  2542 
  2543 * Theory Library/Polynomial defines an abstract type 'a poly of
  2544 univariate polynomials with coefficients of type 'a.  In addition to
  2545 the standard ring operations, it also supports div and mod.  Code
  2546 generation is also supported, using list-style constructors.
  2547 
  2548 * Theory Library/Inner_Product defines a class of real_inner for real
  2549 inner product spaces, with an overloaded operation inner :: 'a => 'a
  2550 => real.  Class real_inner is a subclass of real_normed_vector from
  2551 theory RealVector.
  2552 
  2553 * Theory Library/Product_Vector provides instances for the product
  2554 type 'a * 'b of several classes from RealVector and Inner_Product.
  2555 Definitions of addition, subtraction, scalar multiplication, norms,
  2556 and inner products are included.
  2557 
  2558 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  2559 addition to the field operations, numerals and case syntax are also
  2560 supported.
  2561 
  2562 * Theory Library/Diagonalize provides constructive version of Cantor's
  2563 first diagonalization argument.
  2564 
  2565 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  2566 zlcm (for int); carried together from various gcd/lcm developements in
  2567 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  2568 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  2569 may recover tupled syntax as follows:
  2570 
  2571     hide (open) const gcd
  2572     abbreviation gcd where
  2573       "gcd == (%(a, b). GCD.gcd a b)"
  2574     notation (output)
  2575       GCD.gcd ("gcd '(_, _')")
  2576 
  2577 The same works for lcm, zgcd, zlcm.
  2578 
  2579 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  2580 instantiations for algebraic structures.  Removed some duplicate
  2581 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  2582 
  2583 * ML antiquotation @{code} takes a constant as argument and generates
  2584 corresponding code in background and inserts name of the corresponding
  2585 resulting ML value/function/datatype constructor binding in place.
  2586 All occurrences of @{code} with a single ML block are generated
  2587 simultaneously.  Provides a generic and safe interface for
  2588 instrumentalizing code generation.  See
  2589 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  2590 In future you ought to refrain from ad-hoc compiling generated SML
  2591 code on the ML toplevel.  Note that (for technical reasons) @{code}
  2592 cannot refer to constants for which user-defined serializations are
  2593 set.  Refer to the corresponding ML counterpart directly in that
  2594 cases.
  2595 
  2596 * Command 'rep_datatype': instead of theorem names the command now
  2597 takes a list of terms denoting the constructors of the type to be
  2598 represented as datatype.  The characteristic theorems have to be
  2599 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  2600 have disappeared in favour of existing ones:
  2601 
  2602     unit_induct                 ~> unit.induct
  2603     prod_induct                 ~> prod.induct
  2604     sum_induct                  ~> sum.induct
  2605     Suc_Suc_eq                  ~> nat.inject
  2606     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  2607 
  2608 
  2609 *** HOL-Algebra ***
  2610 
  2611 * New locales for orders and lattices where the equivalence relation
  2612 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  2613 locales use a record structure with field eq for the equivalence.
  2614 
  2615 * New theory of factorial domains.
  2616 
  2617 * Units_l_inv and Units_r_inv are now simp rules by default.
  2618 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  2619 and/or r_inv will now also require deletion of these lemmas.
  2620 
  2621 * Renamed the following theorems, INCOMPATIBILITY:
  2622 
  2623 UpperD ~> Upper_memD
  2624 LowerD ~> Lower_memD
  2625 least_carrier ~> least_closed
  2626 greatest_carrier ~> greatest_closed
  2627 greatest_Lower_above ~> greatest_Lower_below
  2628 one_zero ~> carrier_one_zero
  2629 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  2630 
  2631 
  2632 *** HOL-Nominal ***
  2633 
  2634 * Nominal datatypes can now contain type-variables.
  2635 
  2636 * Commands 'nominal_inductive' and 'equivariance' work with local
  2637 theory targets.
  2638 
  2639 * Nominal primrec can now works with local theory targets and its
  2640 specification syntax now conforms to the general format as seen in
  2641 'inductive' etc.
  2642 
  2643 * Method "perm_simp" honours the standard simplifier attributes
  2644 (no_asm), (no_asm_use) etc.
  2645 
  2646 * The new predicate #* is defined like freshness, except that on the
  2647 left hand side can be a set or list of atoms.
  2648 
  2649 * Experimental command 'nominal_inductive2' derives strong induction
  2650 principles for inductive definitions.  In contrast to
  2651 'nominal_inductive', which can only deal with a fixed number of
  2652 binders, it can deal with arbitrary expressions standing for sets of
  2653 atoms to be avoided.  The only inductive definition we have at the
  2654 moment that needs this generalisation is the typing rule for Lets in
  2655 the algorithm W:
  2656 
  2657  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  2658  -----------------------------------------------------------------
  2659          Gamma |- Let x be t1 in t2 : T2
  2660 
  2661 In this rule one wants to avoid all the binders that are introduced by
  2662 "close Gamma T1".  We are looking for other examples where this
  2663 feature might be useful.  Please let us know.
  2664 
  2665 
  2666 *** HOLCF ***
  2667 
  2668 * Reimplemented the simplification procedure for proving continuity
  2669 subgoals.  The new simproc is extensible; users can declare additional
  2670 continuity introduction rules with the attribute [cont2cont].
  2671 
  2672 * The continuity simproc now uses a different introduction rule for
  2673 solving continuity subgoals on terms with lambda abstractions.  In
  2674 some rare cases the new simproc may fail to solve subgoals that the
  2675 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  2676 Potential INCOMPATIBILITY.
  2677 
  2678 * Command 'fixrec': specification syntax now conforms to the general
  2679 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  2680 examples.  INCOMPATIBILITY.
  2681 
  2682 
  2683 *** ZF ***
  2684 
  2685 * Proof of Zorn's Lemma for partial orders.
  2686 
  2687 
  2688 *** ML ***
  2689 
  2690 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  2691 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  2692 depends on multithreading, so timouts will not work before Poly/ML
  2693 5.2.1!
  2694 
  2695 * High-level support for concurrent ML programming, see
  2696 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  2697 particularly convenient to organize independent functional
  2698 computations.  The concept of "synchronized variables" provides a
  2699 higher-order interface for components with shared state, avoiding the
  2700 delicate details of mutexes and condition variables.  (Requires
  2701 Poly/ML 5.2.1 or later.)
  2702 
  2703 * ML bindings produced via Isar commands are stored within the Isar
  2704 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2705 become thread-safe and work with undo as expected (concerning
  2706 top-level bindings, not side-effects on global references).
  2707 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2708 compiler at runtime; really global bindings need to be given outside a
  2709 theory.  (Requires Poly/ML 5.2 or later.)
  2710 
  2711 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2712 context.  Top-level ML bindings are stored within the proof context in
  2713 a purely sequential fashion, disregarding the nested proof structure.
  2714 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2715 proof.  (Requires Poly/ML 5.2 or later.)
  2716 
  2717 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2718 and Method.setup, as well as Isar commands 'attribute_setup' and
  2719 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2720 existing code accordingly, or use plain 'setup' together with old
  2721 Method.add_method.
  2722 
  2723 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2724 to 'a -> thm, while results are always tagged with an authentic oracle
  2725 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2726 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2727 accordingly.  Note that extra performance may be gained by producing
  2728 the cterm carefully, avoiding slow Thm.cterm_of.
  2729 
  2730 * Simplified interface for defining document antiquotations via
  2731 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2732 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2733 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2734 examples.
  2735 
  2736 * More systematic treatment of long names, abstract name bindings, and
  2737 name space operations.  Basic operations on qualified names have been
  2738 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2739 Long_Name.append.  Old type bstring has been mostly replaced by
  2740 abstract type binding (see structure Binding), which supports precise
  2741 qualification by packages and local theory targets, as well as proper
  2742 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2743 bstring values into Binding.name, or better pass through abstract
  2744 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2745 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2746 
  2747 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2748 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2749 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2750 
  2751 * Disposed old type and term read functions (Sign.read_def_typ,
  2752 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2753 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2754 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2755 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2756 resort for legacy applications.
  2757 
  2758 * Disposed old declarations, tactics, tactic combinators that refer to
  2759 the simpset or claset of an implicit theory (such as Addsimps,
  2760 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2761 embedded ML text, or local_simpset_of with a proper context passed as
  2762 explicit runtime argument.
  2763 
  2764 * Rules and tactics that read instantiations (read_instantiate,
  2765 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2766 context, which is required for parsing and type-checking.  Moreover,
  2767 the variables are specified as plain indexnames, not string encodings
  2768 thereof.  INCOMPATIBILITY.
  2769 
  2770 * Generic Toplevel.add_hook interface allows to analyze the result of
  2771 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2772 for theorem dependency output of transactions resulting in a new
  2773 theory state.
  2774 
  2775 * ML antiquotations: block-structured compilation context indicated by
  2776 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2777 
  2778   @{binding name}                         - basic name binding
  2779   @{let ?pat = term}                      - term abbreviation (HO matching)
  2780   @{note name = fact}                     - fact abbreviation
  2781   @{thm fact}                             - singleton fact (with attributes)
  2782   @{thms fact}                            - general fact (with attributes)
  2783   @{lemma prop by method}                 - singleton goal
  2784   @{lemma prop by meth1 meth2}            - singleton goal
  2785   @{lemma prop1 ... propN by method}      - general goal
  2786   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2787   @{lemma (open) ...}                     - open derivation
  2788 
  2789 
  2790 *** System ***
  2791 
  2792 * The Isabelle "emacs" tool provides a specific interface to invoke
  2793 Proof General / Emacs, with more explicit failure if that is not
  2794 installed (the old isabelle-interface script silently falls back on
  2795 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2796 installation location of the Proof General distribution.
  2797 
  2798 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2799 the Isabelle process into a JVM/Scala application.  See
  2800 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2801 process wrapper has been discontinued.)
  2802 
  2803 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2804 
  2805 * Various status messages (with exact source position information) are
  2806 emitted, if proper markup print mode is enabled.  This allows
  2807 user-interface components to provide detailed feedback on internal
  2808 prover operations.
  2809 
  2810 
  2811 
  2812 New in Isabelle2008 (June 2008)
  2813 -------------------------------
  2814 
  2815 *** General ***
  2816 
  2817 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2818 and updated, with formally checked references as hyperlinks.
  2819 
  2820 * Theory loader: use_thy (and similar operations) no longer set the
  2821 implicit ML context, which was occasionally hard to predict and in
  2822 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2823 provides a proper context already.
  2824 
  2825 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2826 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2827 'use' within a theory file will do the job.
  2828 
  2829 * Name space merge now observes canonical order, i.e. the second space
  2830 is inserted into the first one, while existing entries in the first
  2831 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2832 swap theory imports.
  2833 
  2834 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2835 INCOMPATIBILITY in identifier syntax etc.
  2836 
  2837 * Outer syntax: string tokens no longer admit escaped white space,
  2838 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2839 white space without escapes.
  2840 
  2841 * Outer syntax: string tokens may contain arbitrary character codes
  2842 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2843 "foo_bar".
  2844 
  2845 
  2846 *** Pure ***
  2847 
  2848 * Context-dependent token translations.  Default setup reverts locally
  2849 fixed variables, and adds hilite markup for undeclared frees.
  2850 
  2851 * Unused theorems can be found using the new command 'unused_thms'.
  2852 There are three ways of invoking it:
  2853 
  2854 (1) unused_thms
  2855      Only finds unused theorems in the current theory.
  2856 
  2857 (2) unused_thms thy_1 ... thy_n -
  2858      Finds unused theorems in the current theory and all of its ancestors,
  2859      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2860 
  2861 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2862      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2863      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2864      their ancestors.
  2865 
  2866 In order to increase the readability of the list produced by
  2867 unused_thms, theorems that have been created by a particular instance
  2868 of a theory command such as 'inductive' or 'function' are considered
  2869 to belong to the same "group", meaning that if at least one theorem in
  2870 this group is used, the other theorems in the same group are no longer
  2871 reported as unused.  Moreover, if all theorems in the group are
  2872 unused, only one theorem in the group is displayed.
  2873 
  2874 Note that proof objects have to be switched on in order for
  2875 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2876 usually the case when using Proof General with the default settings).
  2877 
  2878 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2879 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2880 duplicate fact bindings, or even accidental fact duplications.  Note
  2881 that tools may maintain dynamically scoped facts systematically, using
  2882 PureThy.add_thms_dynamic.
  2883 
  2884 * Command 'hide' now allows to hide from "fact" name space as well.
  2885 
  2886 * Eliminated destructive theorem database, simpset, claset, and
  2887 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2888 update of theories within ML code.
  2889 
  2890 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2891 INCOMPATIBILITY, object-logics depending on former Pure require
  2892 additional setup PureThy.old_appl_syntax_setup; object-logics
  2893 depending on former CPure need to refer to Pure.
  2894 
  2895 * Commands 'use' and 'ML' are now purely functional, operating on
  2896 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2897 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2898 INCOMPATIBILITY.
  2899 
  2900 * Command 'setup': discontinued implicit version with ML reference.
  2901 
  2902 * Instantiation target allows for simultaneous specification of class
  2903 instance operations together with an instantiation proof.
  2904 Type-checking phase allows to refer to class operations uniformly.
  2905 See src/HOL/Complex/Complex.thy for an Isar example and
  2906 src/HOL/Library/Eval.thy for an ML example.
  2907 
  2908 * Indexing of literal facts: be more serious about including only
  2909 facts from the visible specification/proof context, but not the
  2910 background context (locale etc.).  Affects `prop` notation and method
  2911 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2912 situations.
  2913 
  2914 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2915 "(open)" option, which used to expose internal bound variables to the
  2916 proof text.
  2917 
  2918 * Isar statements: removed obsolete case "rule_context".
  2919 INCOMPATIBILITY, better use explicit fixes/assumes.
  2920 
  2921 * Locale proofs: default proof step now includes 'unfold_locales';
  2922 hence 'proof' without argument may be used to unfold locale
  2923 predicates.
  2924 
  2925 
  2926 *** Document preparation ***
  2927 
  2928 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2929 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2930 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2931 spot); renamed link color from "darkblue" to "linkcolor" (default
  2932 value unchanged, can be redefined via \definecolor); no longer sets
  2933 "a4paper" option (unnecessary or even intrusive).
  2934 
  2935 * Antiquotation @{lemma A method} proves proposition A by the given
  2936 method (either a method name or a method name plus (optional) method
  2937 arguments in parentheses) and prints A just like @{prop A}.
  2938 
  2939 
  2940 *** HOL ***
  2941 
  2942 * New primrec package.  Specification syntax conforms in style to
  2943 definition/function/....  No separate induction rule is provided.  The
  2944 "primrec" command distinguishes old-style and new-style specifications
  2945 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2946 When adjusting theories, beware: constants stemming from new-style
  2947 primrec specifications have authentic syntax.
  2948 
  2949 * Metis prover is now an order of magnitude faster, and also works
  2950 with multithreading.
  2951 
  2952 * Metis: the maximum number of clauses that can be produced from a
  2953 theorem is now given by the attribute max_clauses.  Theorems that
  2954 exceed this number are ignored, with a warning printed.
  2955 
  2956 * Sledgehammer no longer produces structured proofs by default. To
  2957 enable, declare [[sledgehammer_full = true]].  Attributes
  2958 reconstruction_modulus, reconstruction_sorts renamed
  2959 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2960 
  2961 * Method "induct_scheme" derives user-specified induction rules
  2962 from well-founded induction and completeness of patterns. This factors
  2963 out some operations that are done internally by the function package
  2964 and makes them available separately.  See
  2965 src/HOL/ex/Induction_Scheme.thy for examples.
  2966 
  2967 * More flexible generation of measure functions for termination
  2968 proofs: Measure functions can be declared by proving a rule of the
  2969 form "is_measure f" and giving it the [measure_function] attribute.
  2970 The "is_measure" predicate is logically meaningless (always true), and
  2971 just guides the heuristic.  To find suitable measure functions, the
  2972 termination prover sets up the goal "is_measure ?f" of the appropriate
  2973 type and generates all solutions by prolog-style backwards proof using
  2974 the declared rules.
  2975 
  2976 This setup also deals with rules like 
  2977 
  2978   "is_measure f ==> is_measure (list_size f)"
  2979 
  2980 which accommodates nested datatypes that recurse through lists.
  2981 Similar rules are predeclared for products and option types.
  2982 
  2983 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  2984 
  2985   INCOMPATIBILITIES:
  2986 
  2987   - Definitions of overloaded constants on sets have to be replaced by
  2988     definitions on => and bool.
  2989 
  2990   - Some definitions of overloaded operators on sets can now be proved
  2991     using the definitions of the operators on => and bool.  Therefore,
  2992     the following theorems have been renamed:
  2993 
  2994       subset_def   -> subset_eq
  2995       psubset_def  -> psubset_eq
  2996       set_diff_def -> set_diff_eq
  2997       Compl_def    -> Compl_eq
  2998       Sup_set_def  -> Sup_set_eq
  2999       Inf_set_def  -> Inf_set_eq
  3000       sup_set_def  -> sup_set_eq
  3001       inf_set_def  -> inf_set_eq
  3002 
  3003   - Due to the incompleteness of the HO unification algorithm, some
  3004     rules such as subst may require manual instantiation, if some of
  3005     the unknowns in the rule is a set.
  3006 
  3007   - Higher order unification and forward proofs:
  3008     The proof pattern
  3009 
  3010       have "P (S::'a set)" <...>
  3011       then have "EX S. P S" ..
  3012 
  3013     no longer works (due to the incompleteness of the HO unification
  3014     algorithm) and must be replaced by the pattern
  3015 
  3016       have "EX S. P S"
  3017       proof
  3018         show "P S" <...>
  3019       qed
  3020 
  3021   - Calculational reasoning with subst (or similar rules):
  3022     The proof pattern
  3023 
  3024       have "P (S::'a set)" <...>
  3025       also have "S = T" <...>
  3026       finally have "P T" .
  3027 
  3028     no longer works (for similar reasons as the previous example) and
  3029     must be replaced by something like
  3030 
  3031       have "P (S::'a set)" <...>
  3032       moreover have "S = T" <...>
  3033       ultimately have "P T" by simp
  3034 
  3035   - Tactics or packages written in ML code:
  3036     Code performing pattern matching on types via
  3037 
  3038       Type ("set", [T]) => ...
  3039 
  3040     must be rewritten. Moreover, functions like strip_type or
  3041     binder_types no longer return the right value when applied to a
  3042     type of the form
  3043 
  3044       T1 => ... => Tn => U => bool
  3045 
  3046     rather than
  3047 
  3048       T1 => ... => Tn => U set
  3049 
  3050 * Merged theories Wellfounded_Recursion, Accessible_Part and
  3051 Wellfounded_Relations to theory Wellfounded.
  3052 
  3053 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  3054 
  3055 * Class finite no longer treats UNIV as class parameter.  Use class
  3056 enum from theory Library/Enum instead to achieve a similar effect.
  3057 INCOMPATIBILITY.
  3058 
  3059 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  3060 and "Cons".  INCOMPATIBILITY.
  3061 
  3062 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  3063 Potential INCOMPATIBILITY.
  3064 
  3065 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  3066 injective_fst_snd removed, use split_eta and prod_eqI instead.
  3067 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  3068 
  3069 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  3070 the same name in theory Orderings:
  3071 
  3072   less_trans
  3073   less_linear
  3074   le_imp_less_or_eq
  3075   le_less_trans
  3076   less_le_trans
  3077   less_not_sym
  3078   less_asym
  3079 
  3080 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  3081 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  3082 and different variable names.
  3083 
  3084 * Library/Option_ord.thy: Canonical order on option type.
  3085 
  3086 * Library/RBT.thy: Red-black trees, an efficient implementation of
  3087 finite maps.
  3088 
  3089 * Library/Countable.thy: Type class for countable types.
  3090 
  3091 * Theory Int: The representation of numerals has changed.  The infix
  3092 operator BIT and the bit datatype with constructors B0 and B1 have
  3093 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  3094 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  3095 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  3096 accordingly.
  3097 
  3098 * Theory Nat: definition of <= and < on natural numbers no longer
  3099 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  3100 le_def and less_def have disappeared.  Consider lemmas not_less
  3101 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  3102 
  3103 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  3104 (whose purpose mainly is for various fold_set functionals) have been
  3105 abandoned in favor of the existing algebraic classes
  3106 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  3107 lower_semilattice (resp. upper_semilattice) and linorder.
  3108 INCOMPATIBILITY.
  3109 
  3110 * Theory Transitive_Closure: induct and cases rules now declare proper
  3111 case_names ("base" and "step").  INCOMPATIBILITY.
  3112 
  3113 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  3114 lattices.  The form set-specific version is available as
  3115 Inductive.lfp_ordinal_induct_set.
  3116 
  3117 * Renamed theorems "power.simps" to "power_int.simps".
  3118 INCOMPATIBILITY.
  3119 
  3120 * Class semiring_div provides basic abstract properties of semirings
  3121 with division and modulo operations.  Subsumes former class dvd_mod.
  3122 
  3123 * Merged theories IntDef, Numeral and IntArith into unified theory
  3124 Int.  INCOMPATIBILITY.
  3125 
  3126 * Theory Library/Code_Index: type "index" now represents natural
  3127 numbers rather than integers.  INCOMPATIBILITY.
  3128 
  3129 * New class "uminus" with operation "uminus" (split of from class
  3130 "minus" which now only has operation "minus", binary).
  3131 INCOMPATIBILITY.
  3132 
  3133 * Constants "card", "internal_split", "option_map" now with authentic
  3134 syntax.  INCOMPATIBILITY.
  3135 
  3136 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  3137 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  3138 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  3139 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  3140 Sup_set_def, le_def, less_def, option_map_def now with object
  3141 equality.  INCOMPATIBILITY.
  3142 
  3143 * Records. Removed K_record, and replaced it by pure lambda term
  3144 %x. c. The simplifier setup is now more robust against eta expansion.
  3145 INCOMPATIBILITY: in cases explicitly referring to K_record.
  3146 
  3147 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  3148 
  3149 * Library/ListVector: new theory of arithmetic vector operations.
  3150 
  3151 * Library/Order_Relation: new theory of various orderings as sets of
  3152 pairs.  Defines preorders, partial orders, linear orders and
  3153 well-orders on sets and on types.
  3154 
  3155 
  3156 *** ZF ***
  3157 
  3158 * Renamed some theories to allow to loading both ZF and HOL in the
  3159 same session:
  3160 
  3161   Datatype  -> Datatype_ZF
  3162   Inductive -> Inductive_ZF
  3163   Int       -> Int_ZF
  3164   IntDiv    -> IntDiv_ZF
  3165   Nat       -> Nat_ZF
  3166   List      -> List_ZF
  3167   Main      -> Main_ZF
  3168 
  3169 INCOMPATIBILITY: ZF theories that import individual theories below
  3170 Main might need to be adapted.  Regular theory Main is still
  3171 available, as trivial extension of Main_ZF.
  3172 
  3173 
  3174 *** ML ***
  3175 
  3176 * ML within Isar: antiquotation @{const name} or @{const
  3177 name(typargs)} produces statically-checked Const term.
  3178 
  3179 * Functor NamedThmsFun: data is available to the user as dynamic fact
  3180 (of the same name).  Removed obsolete print command.
  3181 
  3182 * Removed obsolete "use_legacy_bindings" function.
  3183 
  3184 * The ``print mode'' is now a thread-local value derived from a global
  3185 template (the former print_mode reference), thus access becomes
  3186 non-critical.  The global print_mode reference is for session
  3187 management only; user-code should use print_mode_value,
  3188 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  3189 
  3190 * Functions system/system_out provide a robust way to invoke external
  3191 shell commands, with propagation of interrupts (requires Poly/ML
  3192 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  3193 
  3194 
  3195 *** System ***
  3196 
  3197 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  3198 in accordance with Proof General 3.7, which prefers GNU emacs.
  3199 
  3200 * isatool tty runs Isabelle process with plain tty interaction;
  3201 optional line editor may be specified via ISABELLE_LINE_EDITOR
  3202 setting, the default settings attempt to locate "ledit" and "rlwrap".
  3203 
  3204 * isatool browser now works with Cygwin as well, using general
  3205 "javapath" function defined in Isabelle process environment.
  3206 
  3207 * YXML notation provides a simple and efficient alternative to
  3208 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  3209 isatool yxml as described in the Isabelle system manual.
  3210 
  3211 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  3212 provides general wrapper for managing an Isabelle process in a robust
  3213 fashion, with ``cooked'' output from stdin/stderr.
  3214 
  3215 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  3216 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  3217 
  3218 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  3219 way of changing the user's settings is via
  3220 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  3221 script.
  3222 
  3223 * Multithreading.max_threads := 0 refers to the number of actual CPU
  3224 cores of the underlying machine, which is a good starting point for
  3225 optimal performance tuning.  The corresponding usedir option -M allows
  3226 "max" as an alias for "0".  WARNING: does not work on certain versions
  3227 of Mac OS (with Poly/ML 5.1).
  3228 
  3229 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  3230 adverse effect of Isabelle flooding interactive front-ends (notably
  3231 ProofGeneral / XEmacs).
  3232 
  3233 
  3234 
  3235 New in Isabelle2007 (November 2007)
  3236 -----------------------------------
  3237 
  3238 *** General ***
  3239 
  3240 * More uniform information about legacy features, notably a
  3241 warning/error of "Legacy feature: ...", depending on the state of the
  3242 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  3243 legacy features will disappear eventually.
  3244 
  3245 * Theory syntax: the header format ``theory A = B + C:'' has been
  3246 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  3247 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  3248 
  3249 * Theory syntax: the old non-Isar theory file format has been
  3250 discontinued altogether.  Note that ML proof scripts may still be used
  3251 with Isar theories; migration is usually quite simple with the ML
  3252 function use_legacy_bindings.  INCOMPATIBILITY.
  3253 
  3254 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  3255 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  3256 quotes.
  3257 
  3258 * Theory loader: be more serious about observing the static theory
  3259 header specifications (including optional directories), but not the
  3260 accidental file locations of previously successful loads.  The strict
  3261 update policy of former update_thy is now already performed by
  3262 use_thy, so the former has been removed; use_thys updates several
  3263 theories simultaneously, just as 'imports' within a theory header
  3264 specification, but without merging the results.  Potential
  3265 INCOMPATIBILITY: may need to refine theory headers and commands
  3266 ROOT.ML which depend on load order.
  3267 
  3268 * Theory loader: optional support for content-based file
  3269 identification, instead of the traditional scheme of full physical
  3270 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  3271 (cf. the system manual).  The new scheme allows to work with
  3272 non-finished theories in persistent session images, such that source
  3273 files may be moved later on without requiring reloads.
  3274 
  3275 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3276 file (with the same base name as the theory) are considered a legacy
  3277 feature, which will disappear eventually. Even now, the theory loader
  3278 no longer maintains dependencies on such files.
  3279 
  3280 * Syntax: the scope for resolving ambiguities via type-inference is
  3281 now limited to individual terms, instead of whole simultaneous
  3282 specifications as before. This greatly reduces the complexity of the
  3283 syntax module and improves flexibility by separating parsing and
  3284 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  3285 'fixes' etc.) are required in rare situations.
  3286 
  3287 * Syntax: constants introduced by new-style packages ('definition',
  3288 'abbreviation' etc.) are passed through the syntax module in
  3289 ``authentic mode''. This means that associated mixfix annotations
  3290 really stick to such constants, independently of potential name space
  3291 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  3292 trees are represented slightly differently, may need to adapt syntax
  3293 translations accordingly. Use CONST marker in 'translations' and
  3294 @{const_syntax} antiquotation in 'parse_translation' etc.
  3295 
  3296 * Legacy goal package: reduced interface to the bare minimum required
  3297 to keep existing proof scripts running.  Most other user-level
  3298 functions are now part of the OldGoals structure, which is *not* open
  3299 by default (consider isatool expandshort before open OldGoals).
  3300 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  3301 these tend to cause confusion about the actual goal (!) context being
  3302 used here, which is not necessarily the same as the_context().
  3303 
  3304 * Command 'find_theorems': supports "*" wild-card in "name:"
  3305 criterion; "with_dups" option.  Certain ProofGeneral versions might
  3306 support a specific search form (see ProofGeneral/CHANGES).
  3307 
  3308 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  3309 by default, which means that "prems" (and also "fixed variables") are
  3310 suppressed from proof state output.  Note that the ProofGeneral
  3311 settings mechanism allows to change and save options persistently, but
  3312 older versions of Isabelle will fail to start up if a negative prems
  3313 limit is imposed.
  3314 
  3315 * Local theory targets may be specified by non-nested blocks of
  3316 ``context/locale/class ... begin'' followed by ``end''.  The body may
  3317 contain definitions, theorems etc., including any derived mechanism
  3318 that has been implemented on top of these primitives.  This concept
  3319 generalizes the existing ``theorem (in ...)'' towards more versatility
  3320 and scalability.
  3321 
  3322 * Proof General interface: proper undo of final 'end' command;
  3323 discontinued Isabelle/classic mode (ML proof scripts).
  3324 
  3325 
  3326 *** Document preparation ***
  3327 
  3328 * Added antiquotation @{theory name} which prints the given name,
  3329 after checking that it refers to a valid ancestor theory in the
  3330 current context.
  3331 
  3332 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  3333 check the given source text as ML type/structure, printing verbatim.
  3334 
  3335 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  3336 "c args == rhs" given in the current context.  (Any number of
  3337 arguments may be given on the LHS.)
  3338 
  3339 
  3340 *** Pure ***
  3341 
  3342 * The 'class' package offers a combination of axclass and locale to
  3343 achieve Haskell-like type classes in Isabelle.  Definitions and
  3344 theorems within a class context produce both relative results (with
  3345 implicit parameters according to the locale context), and polymorphic
  3346 constants with qualified polymorphism (according to the class
  3347 context).  Within the body context of a 'class' target, a separate
  3348 syntax layer ("user space type system") takes care of converting
  3349 between global polymorphic consts and internal locale representation.
  3350 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  3351 "isatool doc classes" provides a tutorial.
  3352 
  3353 * Generic code generator framework allows to generate executable
  3354 code for ML and Haskell (including Isabelle classes).  A short usage
  3355 sketch:
  3356 
  3357     internal compilation:
  3358         export_code <list of constants (term syntax)> in SML
  3359     writing SML code to a file:
  3360         export_code <list of constants (term syntax)> in SML <filename>
  3361     writing OCaml code to a file:
  3362         export_code <list of constants (term syntax)> in OCaml <filename>
  3363     writing Haskell code to a bunch of files:
  3364         export_code <list of constants (term syntax)> in Haskell <filename>
  3365 
  3366     evaluating closed propositions to True/False using code generation:
  3367         method ``eval''
  3368 
  3369 Reasonable default setup of framework in HOL.
  3370 
  3371 Theorem attributs for selecting and transforming function equations theorems:
  3372 
  3373     [code fun]:        select a theorem as function equation for a specific constant
  3374     [code fun del]:    deselect a theorem as function equation for a specific constant
  3375     [code inline]:     select an equation theorem for unfolding (inlining) in place
  3376     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  3377 
  3378 User-defined serializations (target in {SML, OCaml, Haskell}):
  3379 
  3380     code_const <and-list of constants (term syntax)>
  3381       {(target) <and-list of const target syntax>}+
  3382 
  3383     code_type <and-list of type constructors>
  3384       {(target) <and-list of type target syntax>}+
  3385 
  3386     code_instance <and-list of instances>
  3387       {(target)}+
  3388         where instance ::= <type constructor> :: <class>
  3389 
  3390     code_class <and_list of classes>
  3391       {(target) <and-list of class target syntax>}+
  3392         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  3393 
  3394 code_instance and code_class only are effective to target Haskell.
  3395 
  3396 For example usage see src/HOL/ex/Codegenerator.thy and
  3397 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  3398 generation from Isabelle/HOL theories is available via "isatool doc
  3399 codegen".
  3400 
  3401 * Code generator: consts in 'consts_code' Isar commands are now
  3402 referred to by usual term syntax (including optional type
  3403 annotations).
  3404 
  3405 * Command 'no_translations' removes translation rules from theory
  3406 syntax.
  3407 
  3408 * Overloaded definitions are now actually checked for acyclic
  3409 dependencies.  The overloading scheme is slightly more general than
  3410 that of Haskell98, although Isabelle does not demand an exact
  3411 correspondence to type class and instance declarations.
  3412 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  3413 exotic versions of overloading -- at the discretion of the user!
  3414 
  3415 Polymorphic constants are represented via type arguments, i.e. the
  3416 instantiation that matches an instance against the most general
  3417 declaration given in the signature.  For example, with the declaration
  3418 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  3419 as c(nat).  Overloading is essentially simultaneous structural
  3420 recursion over such type arguments.  Incomplete specification patterns
  3421 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  3422 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  3423 Command 'print_theory' outputs the normalized system of recursive
  3424 equations, see section "definitions".
  3425 
  3426 * Configuration options are maintained within the theory or proof
  3427 context (with name and type bool/int/string), providing a very simple
  3428 interface to a poor-man's version of general context data.  Tools may
  3429 declare options in ML (e.g. using Attrib.config_int) and then refer to
  3430 these values using Config.get etc.  Users may change options via an
  3431 associated attribute of the same name.  This form of context
  3432 declaration works particularly well with commands 'declare' or
  3433 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  3434 very easy to avoid global references, which would not observe Isar
  3435 toplevel undo/redo and fail to work with multithreading.
  3436 
  3437 Various global ML references of Pure and HOL have been turned into
  3438 configuration options:
  3439 
  3440   Unify.search_bound		unify_search_bound
  3441   Unify.trace_bound		unify_trace_bound
  3442   Unify.trace_simp		unify_trace_simp
  3443   Unify.trace_types		unify_trace_types
  3444   Simplifier.simp_depth_limit	simp_depth_limit
  3445   Blast.depth_limit		blast_depth_limit
  3446   DatatypeProp.dtK		datatype_distinctness_limit
  3447   fast_arith_neq_limit  	fast_arith_neq_limit
  3448   fast_arith_split_limit	fast_arith_split_limit
  3449 
  3450 * Named collections of theorems may be easily installed as context
  3451 data using the functor NamedThmsFun (see also
  3452 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  3453 attributes; there is also a toplevel print command.  This facility is
  3454 just a common case of general context data, which is the preferred way
  3455 for anything more complex than just a list of facts in canonical
  3456 order.
  3457 
  3458 * Isar: command 'declaration' augments a local theory by generic
  3459 declaration functions written in ML.  This enables arbitrary content
  3460 being added to the context, depending on a morphism that tells the
  3461 difference of the original declaration context wrt. the application
  3462 context encountered later on.
  3463 
  3464 * Isar: proper interfaces for simplification procedures.  Command
  3465 'simproc_setup' declares named simprocs (with match patterns, and body
  3466 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  3467 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  3468 
  3469 * Isar: an extra pair of brackets around attribute declarations
  3470 abbreviates a theorem reference involving an internal dummy fact,
  3471 which will be ignored later --- only the effect of the attribute on
  3472 the background context will persist.  This form of in-place
  3473 declarations is particularly useful with commands like 'declare' and
  3474 'using', for example ``have A using [[simproc a]] by simp''.
  3475 
  3476 * Isar: method "assumption" (and implicit closing of subproofs) now
  3477 takes simple non-atomic goal assumptions into account: after applying
  3478 an assumption as a rule the resulting subgoals are solved by atomic
  3479 assumption steps.  This is particularly useful to finish 'obtain'
  3480 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  3481 without referring to the original premise "!!x. P x ==> thesis" in the
  3482 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  3483 more permissive.
  3484 
  3485 * Isar: implicit use of prems from the Isar proof context is
  3486 considered a legacy feature.  Common applications like ``have A .''
  3487 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  3488 referencing facts explicitly here improves readability and
  3489 maintainability of proof texts.
  3490 
  3491 * Isar: improper proof element 'guess' is like 'obtain', but derives
  3492 the obtained context from the course of reasoning!  For example:
  3493 
  3494   assume "EX x y. A x & B y"   -- "any previous fact"
  3495   then guess x and y by clarify
  3496 
  3497 This technique is potentially adventurous, depending on the facts and
  3498 proof tools being involved here.
  3499 
  3500 * Isar: known facts from the proof context may be specified as literal
  3501 propositions, using ASCII back-quote syntax.  This works wherever
  3502 named facts used to be allowed so far, in proof commands, proof
  3503 methods, attributes etc.  Literal facts are retrieved from the context
  3504 according to unification of type and term parameters.  For example,
  3505 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  3506 theorems in the current context, then these are valid literal facts:
  3507 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  3508 
  3509 There is also a proof method "fact" which does the same composition
  3510 for explicit goal states, e.g. the following proof texts coincide with
  3511 certain special cases of literal facts:
  3512 
  3513   have "A" by fact                 ==  note `A`
  3514   have "A ==> B" by fact           ==  note `A ==> B`
  3515   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  3516   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  3517 
  3518 * Isar: ":" (colon) is no longer a symbolic identifier character in
  3519 outer syntax.  Thus symbolic identifiers may be used without
  3520 additional white space in declarations like this: ``assume *: A''.
  3521 
  3522 * Isar: 'print_facts' prints all local facts of the current context,
  3523 both named and unnamed ones.
  3524 
  3525 * Isar: 'def' now admits simultaneous definitions, e.g.:
  3526 
  3527   def x == "t" and y == "u"
  3528 
  3529 * Isar: added command 'unfolding', which is structurally similar to
  3530 'using', but affects both the goal state and facts by unfolding given
  3531 rewrite rules.  Thus many occurrences of the 'unfold' method or
  3532 'unfolded' attribute may be replaced by first-class proof text.
  3533 
  3534 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  3535 and command 'unfolding' now all support object-level equalities
  3536 (potentially conditional).  The underlying notion of rewrite rule is
  3537 analogous to the 'rule_format' attribute, but *not* that of the
  3538 Simplifier (which is usually more generous).
  3539 
  3540 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  3541 premises of a theorem by n. Useful in conjunction with drule.
  3542 
  3543 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  3544 method expression within a sandbox consisting of the first N
  3545 sub-goals, which need to exist.  For example, ``simp_all [3]''
  3546 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  3547 simplifies all new goals that emerge from applying rule foo to the
  3548 originally first one.
  3549 
  3550 * Isar: schematic goals are no longer restricted to higher-order
  3551 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  3552 expected.
  3553 
  3554 * Isar: the conclusion of a long theorem statement is now either
  3555 'shows' (a simultaneous conjunction, as before), or 'obtains'
  3556 (essentially a disjunction of cases with local parameters and
  3557 assumptions).  The latter allows to express general elimination rules
  3558 adequately; in this notation common elimination rules look like this:
  3559 
  3560   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  3561     assumes "EX x. P x"
  3562     obtains x where "P x"
  3563 
  3564   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  3565     assumes "A & B"
  3566     obtains A and B
  3567 
  3568   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  3569     assumes "A | B"
  3570     obtains
  3571       A
  3572     | B
  3573 
  3574 The subsequent classical rules even refer to the formal "thesis"
  3575 explicitly:
  3576 
  3577   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  3578     obtains "~ thesis"
  3579 
  3580   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  3581     obtains "thesis ==> something"
  3582 
  3583 The actual proof of an 'obtains' statement is analogous to that of the
  3584 Isar proof element 'obtain', only that there may be several cases.
  3585 Optional case names may be specified in parentheses; these will be
  3586 available both in the present proof and as annotations in the
  3587 resulting rule, for later use with the 'cases' method (cf. attribute
  3588 case_names).
  3589 
  3590 * Isar: the assumptions of a long theorem statement are available as
  3591 "assms" fact in the proof context.  This is more appropriate than the
  3592 (historical) "prems", which refers to all assumptions of the current
  3593 context, including those from the target locale, proof body etc.
  3594 
  3595 * Isar: 'print_statement' prints theorems from the current theory or
  3596 proof context in long statement form, according to the syntax of a
  3597 top-level lemma.
  3598 
  3599 * Isar: 'obtain' takes an optional case name for the local context
  3600 introduction rule (default "that").
  3601 
  3602 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  3603 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  3604 to occur.
  3605 
  3606 * Pure: syntax "CONST name" produces a fully internalized constant
  3607 according to the current context.  This is particularly useful for
  3608 syntax translations that should refer to internal constant
  3609 representations independently of name spaces.
  3610 
  3611 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  3612 instead of "FOO ". This allows multiple binder declarations to coexist
  3613 in the same context.  INCOMPATIBILITY.
  3614 
  3615 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  3616 primitive that also works in a locale context (both for constants and
  3617 fixed variables). Type declaration and internal syntactic representation
  3618 of given constants retrieved from the context. Likewise, the
  3619 'no_notation' command allows to remove given syntax annotations from the
  3620 current context.
  3621 
  3622 * Isar/locales: new derived specification elements 'axiomatization',
  3623 'definition', 'abbreviation', which support type-inference, admit
  3624 object-level specifications (equality, equivalence).  See also the
  3625 isar-ref manual.  Examples:
  3626 
  3627   axiomatization
  3628     eq  (infix "===" 50) where
  3629     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  3630 
  3631   definition "f x y = x + y + 1"
  3632   definition g where "g x = f x x"
  3633 
  3634   abbreviation
  3635     neq  (infix "=!=" 50) where
  3636     "x =!= y == ~ (x === y)"
  3637 
  3638 These specifications may be also used in a locale context.  Then the
  3639 constants being introduced depend on certain fixed parameters, and the
  3640 constant name is qualified by the locale base name.  An internal
  3641 abbreviation takes care for convenient input and output, making the
  3642 parameters implicit and using the original short name.  See also
  3643 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  3644 entities from a monomorphic theory.
  3645 
  3646 Presently, abbreviations are only available 'in' a target locale, but
  3647 not inherited by general import expressions.  Also note that
  3648 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  3649 'translations' in common applications.  The "no_abbrevs" print mode
  3650 prevents folding of abbreviations in term output.
  3651 
  3652 Concrete syntax is attached to specified constants in internal form,
  3653 independently of name spaces.  The parse tree representation is
  3654 slightly different -- use 'notation' instead of raw 'syntax', and
  3655 'translations' with explicit "CONST" markup to accommodate this.
  3656 
  3657 * Pure/Isar: unified syntax for new-style specification mechanisms
  3658 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  3659 full type inference and dummy patterns ("_").  For example:
  3660 
  3661   definition "K x _ = x"
  3662 
  3663   inductive conj for A B
  3664   where "A ==> B ==> conj A B"
  3665 
  3666 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  3667 the current context.  Print mode "no_abbrevs" prevents inversion of
  3668 abbreviations on output.
  3669 
  3670 * Isar/locales: improved parameter handling: use of locales "var" and
  3671 "struct" no longer necessary; - parameter renamings are no longer
  3672 required to be injective.  For example, this allows to define
  3673 endomorphisms as locale endom = homom mult mult h.
  3674 
  3675 * Isar/locales: changed the way locales with predicates are defined.
  3676 Instead of accumulating the specification, the imported expression is
  3677 now an interpretation.  INCOMPATIBILITY: different normal form of
  3678 locale expressions.  In particular, in interpretations of locales with
  3679 predicates, goals repesenting already interpreted fragments are not
  3680 removed automatically.  Use methods `intro_locales' and
  3681 `unfold_locales'; see below.
  3682 
  3683 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  3684 provide backward reasoning on locales predicates.  The methods are
  3685 aware of interpretations and discharge corresponding goals.
  3686 `intro_locales' is less aggressive then `unfold_locales' and does not
  3687 unfold predicates to assumptions.
  3688 
  3689 * Isar/locales: the order in which locale fragments are accumulated
  3690 has changed.  This enables to override declarations from fragments due
  3691 to interpretations -- for example, unwanted simp rules.
  3692 
  3693 * Isar/locales: interpretation in theories and proof contexts has been
  3694 extended.  One may now specify (and prove) equations, which are
  3695 unfolded in interpreted theorems.  This is useful for replacing
  3696 defined concepts (constants depending on locale parameters) by
  3697 concepts already existing in the target context.  Example:
  3698 
  3699   interpretation partial_order ["op <= :: [int, int] => bool"]
  3700     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3701 
  3702 Typically, the constant `partial_order.less' is created by a
  3703 definition specification element in the context of locale
  3704 partial_order.
  3705 
  3706 * Method "induct": improved internal context management to support
  3707 local fixes and defines on-the-fly. Thus explicit meta-level
  3708 connectives !!  and ==> are rarely required anymore in inductive goals
  3709 (using object-logic connectives for this purpose has been long
  3710 obsolete anyway). Common proof patterns are explained in
  3711 src/HOL/Induct/Common_Patterns.thy, see also
  3712 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3713 examples.
  3714 
  3715 * Method "induct": improved handling of simultaneous goals. Instead of
  3716 introducing object-level conjunction, the statement is now split into
  3717 several conclusions, while the corresponding symbolic cases are nested
  3718 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3719 see src/HOL/Induct/Common_Patterns.thy, for example.
  3720 
  3721 * Method "induct": mutual induction rules are now specified as a list
  3722 of rule sharing the same induction cases. HOL packages usually provide
  3723 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3724 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3725 mutual induction rules differently, i.e. like this:
  3726 
  3727   (induct rule: foo_bar.inducts)
  3728   (induct set: foo bar)
  3729   (induct pred: foo bar)
  3730   (induct type: foo bar)
  3731 
  3732 The ML function ProjectRule.projections turns old-style rules into the
  3733 new format.
  3734 
  3735 * Method "coinduct": dual of induction, see
  3736 src/HOL/Library/Coinductive_List.thy for various examples.
  3737 
  3738 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3739 considered a legacy feature.
  3740 
  3741 * Attribute "symmetric" produces result with standardized schematic
  3742 variables (index 0).  Potential INCOMPATIBILITY.
  3743 
  3744 * Simplifier: by default the simplifier trace only shows top level
  3745 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3746 default. Thus there is less danger of being flooded by the trace. The
  3747 trace indicates where parts have been suppressed.
  3748   
  3749 * Provers/classical: removed obsolete classical version of elim_format
  3750 attribute; classical elim/dest rules are now treated uniformly when
  3751 manipulating the claset.
  3752 
  3753 * Provers/classical: stricter checks to ensure that supplied intro,
  3754 dest and elim rules are well-formed; dest and elim rules must have at
  3755 least one premise.
  3756 
  3757 * Provers/classical: attributes dest/elim/intro take an optional
  3758 weight argument for the rule (just as the Pure versions).  Weights are
  3759 ignored by automated tools, but determine the search order of single
  3760 rule steps.
  3761 
  3762 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3763 where the body does not mention the bound variable.  Note that dummy
  3764 patterns implicitly depend on their context of bounds, which makes
  3765 "{_. _}" match any set comprehension as expected.  Potential
  3766 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3767 constant "_idtdummy" in the binding position.
  3768 
  3769 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3770 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3771 for example "A -> B" => "Pi A (%_. B)".
  3772 
  3773 * Pure: 'class_deps' command visualizes the subclass relation, using
  3774 the graph browser tool.
  3775 
  3776 * Pure: 'print_theory' now suppresses certain internal declarations by
  3777 default; use '!' option for full details.
  3778 
  3779 
  3780 *** HOL ***
  3781 
  3782 * Method "metis" proves goals by applying the Metis general-purpose
  3783 resolution prover (see also http://gilith.com/software/metis/).
  3784 Examples are in the directory MetisExamples.  WARNING: the
  3785 Isabelle/HOL-Metis integration does not yet work properly with
  3786 multi-threading.
  3787   
  3788 * Command 'sledgehammer' invokes external automatic theorem provers as
  3789 background processes.  It generates calls to the "metis" method if
  3790 successful. These can be pasted into the proof.  Users do not have to
  3791 wait for the automatic provers to return.  WARNING: does not really
  3792 work with multi-threading.
  3793 
  3794 * New "auto_quickcheck" feature tests outermost goal statements for
  3795 potential counter-examples.  Controlled by ML references
  3796 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3797 5000 milliseconds).  Fails silently if statements is outside of
  3798 executable fragment, or any other codgenerator problem occurs.
  3799 
  3800 * New constant "undefined" with axiom "undefined x = undefined".
  3801 
  3802 * Added class "HOL.eq", allowing for code generation with polymorphic
  3803 equality.
  3804 
  3805 * Some renaming of class constants due to canonical name prefixing in
  3806 the new 'class' package:
  3807 
  3808     HOL.abs ~> HOL.abs_class.abs
  3809     HOL.divide ~> HOL.divide_class.divide
  3810     0 ~> HOL.zero_class.zero
  3811     1 ~> HOL.one_class.one
  3812     op + ~> HOL.plus_class.plus
  3813     op - ~> HOL.minus_class.minus
  3814     uminus ~> HOL.minus_class.uminus
  3815     op * ~> HOL.times_class.times
  3816     op < ~> HOL.ord_class.less
  3817     op <= > HOL.ord_class.less_eq
  3818     Nat.power ~> Power.power_class.power
  3819     Nat.size ~> Nat.size_class.size
  3820     Numeral.number_of ~> Numeral.number_class.number_of
  3821     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3822     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3823     Orderings.min ~> Orderings.ord_class.min
  3824     Orderings.max ~> Orderings.ord_class.max
  3825     Divides.op div ~> Divides.div_class.div
  3826     Divides.op mod ~> Divides.div_class.mod
  3827     Divides.op dvd ~> Divides.div_class.dvd
  3828 
  3829 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3830 
  3831 a) User-defined constants using any of the names "plus", "minus",
  3832 "times", "less" or "less_eq". The standard syntax translations for
  3833 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3834 names.
  3835 
  3836 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3837 INCOMPATIBILITY: use more specific names.
  3838 
  3839 c) Permutative equations (e.g. "a + b = b + a")
  3840 Since the change of names also changes the order of terms, permutative
  3841 rewrite rules may get applied in a different order. Experience shows
  3842 that this is rarely the case (only two adaptions in the whole Isabelle
  3843 distribution).  INCOMPATIBILITY: rewrite proofs
  3844 
  3845 d) ML code directly refering to constant names
  3846 This in general only affects hand-written proof tactics, simprocs and
  3847 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3848 Consider using @{const_name} antiquotation.
  3849 
  3850 * New class "default" with associated constant "default".
  3851 
  3852 * Function "sgn" is now overloaded and available on int, real, complex
  3853 (and other numeric types), using class "sgn".  Two possible defs of
  3854 sgn are given as equational assumptions in the classes sgn_if and
  3855 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3856 INCOMPATIBILITY.
  3857 
  3858 * Locale "partial_order" now unified with class "order" (cf. theory
  3859 Orderings), added parameter "less".  INCOMPATIBILITY.
  3860 
  3861 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3862 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3863 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3864 
  3865 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3866 changed order of proof goals in instance proofs.
  3867 
  3868 * The transitivity reasoner for partial and linear orders is set up
  3869 for classes "order" and "linorder".  Instances of the reasoner are available
  3870 in all contexts importing or interpreting the corresponding locales.
  3871 Method "order" invokes the reasoner separately; the reasoner
  3872 is also integrated with the Simplifier as a solver.  Diagnostic
  3873 command 'print_orders' shows the available instances of the reasoner
  3874 in the current context.
  3875 
  3876 * Localized monotonicity predicate in theory "Orderings"; integrated
  3877 lemmas max_of_mono and min_of_mono with this predicate.
  3878 INCOMPATIBILITY.
  3879 
  3880 * Formulation of theorem "dense" changed slightly due to integration
  3881 with new class dense_linear_order.
  3882 
  3883 * Uniform lattice theory development in HOL.
  3884 
  3885     constants "meet" and "join" now named "inf" and "sup"
  3886     constant "Meet" now named "Inf"
  3887 
  3888     classes "meet_semilorder" and "join_semilorder" now named
  3889       "lower_semilattice" and "upper_semilattice"
  3890     class "lorder" now named "lattice"
  3891     class "comp_lat" now named "complete_lattice"
  3892 
  3893     Instantiation of lattice classes allows explicit definitions
  3894     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3895 
  3896   INCOMPATIBILITY.  Theorem renames:
  3897 
  3898     meet_left_le            ~> inf_le1
  3899     meet_right_le           ~> inf_le2
  3900     join_left_le            ~> sup_ge1
  3901     join_right_le           ~> sup_ge2
  3902     meet_join_le            ~> inf_sup_ord
  3903     le_meetI                ~> le_infI
  3904     join_leI                ~> le_supI
  3905     le_meet                 ~> le_inf_iff
  3906     le_join                 ~> ge_sup_conv
  3907     meet_idempotent         ~> inf_idem
  3908     join_idempotent         ~> sup_idem
  3909     meet_comm               ~> inf_commute
  3910     join_comm               ~> sup_commute
  3911     meet_leI1               ~> le_infI1
  3912     meet_leI2               ~> le_infI2
  3913     le_joinI1               ~> le_supI1
  3914     le_joinI2               ~> le_supI2
  3915     meet_assoc              ~> inf_assoc
  3916     join_assoc              ~> sup_assoc
  3917     meet_left_comm          ~> inf_left_commute
  3918     meet_left_idempotent    ~> inf_left_idem
  3919     join_left_comm          ~> sup_left_commute
  3920     join_left_idempotent    ~> sup_left_idem
  3921     meet_aci                ~> inf_aci
  3922     join_aci                ~> sup_aci
  3923     le_def_meet             ~> le_iff_inf
  3924     le_def_join             ~> le_iff_sup
  3925     join_absorp2            ~> sup_absorb2
  3926     join_absorp1            ~> sup_absorb1
  3927     meet_absorp1            ~> inf_absorb1
  3928     meet_absorp2            ~> inf_absorb2
  3929     meet_join_absorp        ~> inf_sup_absorb
  3930     join_meet_absorp        ~> sup_inf_absorb
  3931     distrib_join_le         ~> distrib_sup_le
  3932     distrib_meet_le         ~> distrib_inf_le
  3933 
  3934     add_meet_distrib_left   ~> add_inf_distrib_left
  3935     add_join_distrib_left   ~> add_sup_distrib_left
  3936     is_join_neg_meet        ~> is_join_neg_inf
  3937     is_meet_neg_join        ~> is_meet_neg_sup
  3938     add_meet_distrib_right  ~> add_inf_distrib_right
  3939     add_join_distrib_right  ~> add_sup_distrib_right
  3940     add_meet_join_distribs  ~> add_sup_inf_distribs
  3941     join_eq_neg_meet        ~> sup_eq_neg_inf
  3942     meet_eq_neg_join        ~> inf_eq_neg_sup
  3943     add_eq_meet_join        ~> add_eq_inf_sup
  3944     meet_0_imp_0            ~> inf_0_imp_0
  3945     join_0_imp_0            ~> sup_0_imp_0
  3946     meet_0_eq_0             ~> inf_0_eq_0
  3947     join_0_eq_0             ~> sup_0_eq_0
  3948     neg_meet_eq_join        ~> neg_inf_eq_sup
  3949     neg_join_eq_meet        ~> neg_sup_eq_inf
  3950     join_eq_if              ~> sup_eq_if
  3951 
  3952     mono_meet               ~> mono_inf
  3953     mono_join               ~> mono_sup
  3954     meet_bool_eq            ~> inf_bool_eq
  3955     join_bool_eq            ~> sup_bool_eq
  3956     meet_fun_eq             ~> inf_fun_eq
  3957     join_fun_eq             ~> sup_fun_eq
  3958     meet_set_eq             ~> inf_set_eq
  3959     join_set_eq             ~> sup_set_eq
  3960     meet1_iff               ~> inf1_iff
  3961     meet2_iff               ~> inf2_iff
  3962     meet1I                  ~> inf1I
  3963     meet2I                  ~> inf2I
  3964     meet1D1                 ~> inf1D1
  3965     meet2D1                 ~> inf2D1
  3966     meet1D2                 ~> inf1D2
  3967     meet2D2                 ~> inf2D2
  3968     meet1E                  ~> inf1E
  3969     meet2E                  ~> inf2E
  3970     join1_iff               ~> sup1_iff
  3971     join2_iff               ~> sup2_iff
  3972     join1I1                 ~> sup1I1
  3973     join2I1                 ~> sup2I1
  3974     join1I1                 ~> sup1I1
  3975     join2I2                 ~> sup1I2
  3976     join1CI                 ~> sup1CI
  3977     join2CI                 ~> sup2CI
  3978     join1E                  ~> sup1E
  3979     join2E                  ~> sup2E
  3980 
  3981     is_meet_Meet            ~> is_meet_Inf
  3982     Meet_bool_def           ~> Inf_bool_def
  3983     Meet_fun_def            ~> Inf_fun_def
  3984     Meet_greatest           ~> Inf_greatest
  3985     Meet_lower              ~> Inf_lower
  3986     Meet_set_def            ~> Inf_set_def
  3987 
  3988     Sup_def                 ~> Sup_Inf
  3989     Sup_bool_eq             ~> Sup_bool_def
  3990     Sup_fun_eq              ~> Sup_fun_def
  3991     Sup_set_eq              ~> Sup_set_def
  3992 
  3993     listsp_meetI            ~> listsp_infI
  3994     listsp_meet_eq          ~> listsp_inf_eq
  3995 
  3996     meet_min                ~> inf_min
  3997     join_max                ~> sup_max
  3998 
  3999 * Added syntactic class "size"; overloaded constant "size" now has
  4000 type "'a::size ==> bool"
  4001 
  4002 * Internal reorganisation of `size' of datatypes: size theorems
  4003 "foo.size" are no longer subsumed by "foo.simps" (but are still
  4004 simplification rules by default!); theorems "prod.size" now named
  4005 "*.size".
  4006 
  4007 * Class "div" now inherits from class "times" rather than "type".
  4008 INCOMPATIBILITY.
  4009 
  4010 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  4011 Linorder etc.  have disappeared; operations defined in terms of
  4012 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  4013 
  4014 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  4015 
  4016 * HOL-Word: New extensive library and type for generic, fixed size
  4017 machine words, with arithemtic, bit-wise, shifting and rotating
  4018 operations, reflection into int, nat, and bool lists, automation for
  4019 linear arithmetic (by automatic reflection into nat or int), including
  4020 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  4021 arithmetic type classes, supporting automatic simplification of
  4022 numerals on all operations.
  4023 
  4024 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  4025 
  4026 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  4027 
  4028 * Code generator library theories:
  4029   - Code_Integer represents HOL integers by big integer literals in target
  4030     languages.
  4031   - Code_Char represents HOL characters by character literals in target
  4032     languages.
  4033   - Code_Char_chr like Code_Char, but also offers treatment of character
  4034     codes; includes Code_Integer.
  4035   - Executable_Set allows to generate code for finite sets using lists.
  4036   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  4037     denominator).
  4038   - Executable_Real implements a subset of real numbers, namly those
  4039     representable by rational numbers.
  4040   - Efficient_Nat implements natural numbers by integers, which in general will
  4041     result in higher efficency; pattern matching with 0/Suc is eliminated;
  4042     includes Code_Integer.
  4043   - Code_Index provides an additional datatype index which is mapped to
  4044     target-language built-in integers.
  4045   - Code_Message provides an additional datatype message_string which is isomorphic to
  4046     strings; messages are mapped to target-language strings.
  4047 
  4048 * New package for inductive predicates
  4049 
  4050   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  4051 
  4052     inductive
  4053       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4054       for z_1 :: U_1 and ... and z_n :: U_m
  4055     where
  4056       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4057     | ...
  4058 
  4059   with full support for type-inference, rather than
  4060 
  4061     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4062 
  4063     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4064     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4065 
  4066     inductive "s z_1 ... z_m"
  4067     intros
  4068       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4069       ...
  4070 
  4071   For backward compatibility, there is a wrapper allowing inductive
  4072   sets to be defined with the new package via
  4073 
  4074     inductive_set
  4075       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4076       for z_1 :: U_1 and ... and z_n :: U_m
  4077     where
  4078       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4079     | ...
  4080 
  4081   or
  4082 
  4083     inductive_set
  4084       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4085       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4086       for z_1 :: U_1 and ... and z_n :: U_m
  4087     where
  4088       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4089     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4090     | ...
  4091 
  4092   if the additional syntax "p ..." is required.
  4093 
  4094   Numerous examples can be found in the subdirectories src/HOL/Auth,
  4095   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  4096 
  4097   INCOMPATIBILITIES:
  4098 
  4099   - Since declaration and definition of inductive sets or predicates
  4100     is no longer separated, abbreviations involving the newly
  4101     introduced sets or predicates must be specified together with the
  4102     introduction rules after the 'where' keyword (see above), rather
  4103     than before the actual inductive definition.
  4104 
  4105   - The variables in induction and elimination rules are now
  4106     quantified in the order of their occurrence in the introduction
  4107     rules, rather than in alphabetical order. Since this may break
  4108     some proofs, these proofs either have to be repaired, e.g. by
  4109     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  4110     statements of the form
  4111 
  4112       case (rule_i a_i_1 ... a_i_{k_i})
  4113 
  4114     or the old order of quantification has to be restored by explicitly adding
  4115     meta-level quantifiers in the introduction rules, i.e.
  4116 
  4117       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  4118 
  4119   - The format of the elimination rules is now
  4120 
  4121       p z_1 ... z_m x_1 ... x_n ==>
  4122         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4123         ==> ... ==> P
  4124 
  4125     for predicates and
  4126 
  4127       (x_1, ..., x_n) : s z_1 ... z_m ==>
  4128         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4129         ==> ... ==> P
  4130 
  4131     for sets rather than
  4132 
  4133       x : s z_1 ... z_m ==>
  4134         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  4135         ==> ... ==> P
  4136 
  4137     This may require terms in goals to be expanded to n-tuples
  4138     (e.g. using case_tac or simplification with the split_paired_all
  4139     rule) before the above elimination rule is applicable.
  4140 
  4141   - The elimination or case analysis rules for (mutually) inductive
  4142     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  4143     list of rules "p_1_..._p_k.elims" is no longer available.
  4144 
  4145 * New package "function"/"fun" for general recursive functions,
  4146 supporting mutual and nested recursion, definitions in local contexts,
  4147 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  4148 for small examples, and the separate tutorial on the function
  4149 package. The old recdef "package" is still available as before, but
  4150 users are encouraged to use the new package.
  4151 
  4152 * Method "lexicographic_order" automatically synthesizes termination
  4153 relations as lexicographic combinations of size measures. 
  4154 
  4155 * Case-expressions allow arbitrary constructor-patterns (including
  4156 "_") and take their order into account, like in functional
  4157 programming.  Internally, this is translated into nested
  4158 case-expressions; missing cases are added and mapped to the predefined
  4159 constant "undefined". In complicated cases printing may no longer show
  4160 the original input but the internal form. Lambda-abstractions allow
  4161 the same form of pattern matching: "% pat1 => e1 | ..." is an
  4162 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  4163 variable.
  4164 
  4165 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  4166 is an abbreviation for "of_nat :: nat => int". The simplification
  4167 rules for "of_nat" have been changed to work like "int" did
  4168 previously.  Potential INCOMPATIBILITY:
  4169   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  4170   - of_nat_diff and of_nat_mult are no longer default simp rules
  4171 
  4172 * Method "algebra" solves polynomial equations over (semi)rings using
  4173 Groebner bases. The (semi)ring structure is defined by locales and the
  4174 tool setup depends on that generic context. Installing the method for
  4175 a specific type involves instantiating the locale and possibly adding
  4176 declarations for computation on the coefficients.  The method is
  4177 already instantiated for natural numbers and for the axiomatic class
  4178 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  4179 CALCULEMUS 2007 for the general principles underlying this
  4180 architecture of context-aware proof-tools.
  4181 
  4182 * Method "ferrack" implements quantifier elimination over
  4183 special-purpose dense linear orders using locales (analogous to
  4184 "algebra"). The method is already installed for class
  4185 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  4186 rat, etc.
  4187 
  4188 * Former constant "List.op @" now named "List.append".  Use ML
  4189 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  4190 circumvent possible incompatibilities when working on ML level.
  4191 
  4192 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  4193 
  4194 * New function listsum :: 'a list => 'a for arbitrary monoids.
  4195 Special syntax: "SUM x <- xs. f x" (and latex variants)
  4196 
  4197 * New syntax for Haskell-like list comprehension (input only), eg.
  4198 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  4199 
  4200 * The special syntax for function "filter" has changed from [x :
  4201 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  4202 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  4203 
  4204 * [a..b] is now defined for arbitrary linear orders.  It used to be
  4205 defined on nat only, as an abbreviation for [a..<Suc b]
  4206 INCOMPATIBILITY.
  4207 
  4208 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  4209 
  4210 * New functions "sorted" and "sort" in src/HOL/List.thy.
  4211 
  4212 * New lemma collection field_simps (an extension of ring_simps) for
  4213 manipulating (in)equations involving division. Multiplies with all
  4214 denominators that can be proved to be non-zero (in equations) or
  4215 positive/negative (in inequations).
  4216 
  4217 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  4218 have been improved and renamed to ring_simps, group_simps and
  4219 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  4220 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  4221 
  4222 * Theory Library/Commutative_Ring: switched from recdef to function
  4223 package; constants add, mul, pow now curried.  Infix syntax for
  4224 algebraic operations.
  4225 
  4226 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  4227 INCOMPATIBILITY.
  4228 
  4229 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  4230 INCOMPATIBILITY.
  4231 
  4232 * HOL/records: generalised field-update to take a function on the
  4233 field rather than the new value: r(|A := x|) is translated to A_update
  4234 (K x) r The K-combinator that is internally used is called K_record.
  4235 INCOMPATIBILITY: Usage of the plain update functions has to be
  4236 adapted.
  4237  
  4238 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  4239 * x = 0, which are required for a semiring.  Richer structures do not
  4240 inherit from semiring_0 anymore, because this property is a theorem
  4241 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  4242 there is more to prove, but this is mostly trivial.
  4243 
  4244 * Class "recpower" is generalized to arbitrary monoids, not just
  4245 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  4246 commutativity or semiring properties additionally.
  4247 
  4248 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  4249 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  4250 better use 'abbreviation'.
  4251 
  4252 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  4253 
  4254 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  4255 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  4256 significant changes for setting up numeral syntax for types:
  4257   - New constants Numeral.pred and Numeral.succ instead
  4258       of former Numeral.bin_pred and Numeral.bin_succ.
  4259   - Use integer operations instead of bin_add, bin_mult and so on.
  4260   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  4261   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  4262 
  4263 See src/HOL/Integ/IntArith.thy for an example setup.
  4264 
  4265 * Command 'normal_form' computes the normal form of a term that may
  4266 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  4267 produces ``[b, c, a]'' (without proof).  This command is suitable for
  4268 heavy-duty computations because the functions are compiled to ML
  4269 first.  Correspondingly, a method "normalization" is provided.  See
  4270 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  4271 
  4272 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  4273 25 like -->); output depends on the "iff" print_mode, the default is
  4274 "A = B" (with priority 50).
  4275 
  4276 * Relations less (<) and less_eq (<=) are also available on type bool.
  4277 Modified syntax to disallow nesting without explicit parentheses,
  4278 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  4279 INCOMPATIBILITY.
  4280 
  4281 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  4282 
  4283 * Relation composition operator "op O" now has precedence 75 and binds
  4284 stronger than union and intersection. INCOMPATIBILITY.
  4285 
  4286 * The old set interval syntax "{m..n(}" (and relatives) has been
  4287 removed.  Use "{m..<n}" (and relatives) instead.
  4288 
  4289 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  4290 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  4291 ``declare [[simproc del: neq]]''.
  4292 
  4293 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  4294 True/False.
  4295 
  4296 * Theorem Cons_eq_map_conv no longer declared as "simp".
  4297 
  4298 * Theorem setsum_mult renamed to setsum_right_distrib.
  4299 
  4300 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  4301 ``rule'' method.
  4302 
  4303 * Reimplemented methods "sat" and "satx", with several improvements:
  4304 goals no longer need to be stated as "<prems> ==> False", equivalences
  4305 (i.e. "=" on type bool) are handled, variable names of the form
  4306 "lit_<n>" are no longer reserved, significant speedup.
  4307 
  4308 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  4309 zChaff is still supported as well.
  4310 
  4311 * 'inductive' and 'datatype': provide projections of mutual rules,
  4312 bundled as foo_bar.inducts;
  4313 
  4314 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  4315 Library.
  4316 
  4317 * Library: moved theory Accessible_Part to main HOL.
  4318 
  4319 * Library: added theory Coinductive_List of potentially infinite lists
  4320 as greatest fixed-point.
  4321 
  4322 * Library: added theory AssocList which implements (finite) maps as
  4323 association lists.
  4324 
  4325 * Method "evaluation" solves goals (i.e. a boolean expression)
  4326 efficiently by compiling it to ML.  The goal is "proved" (via an
  4327 oracle) if it evaluates to True.
  4328 
  4329 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  4330 also when invoked by the simplifier.  This results in the Simplifier
  4331 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  4332 Configuration option fast_arith_split_limit=0 recovers the old
  4333 behavior.
  4334 
  4335 * Support for hex (0x20) and binary (0b1001) numerals.
  4336 
  4337 * New method: reify eqs (t), where eqs are equations for an
  4338 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  4339 parameter, computes a term s::'b and a list xs::'a list and proves the
  4340 theorem I xs s = t. This is also known as reification or quoting. The
  4341 resulting theorem is applied to the subgoal to substitute t with I xs
  4342 s.  If t is omitted, the subgoal itself is reified.
  4343 
  4344 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  4345 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  4346 where f is supposed to be a computable function (in the sense of code
  4347 generattion). The method uses reify to compute s and xs as above then
  4348 applies corr_thm and uses normalization by evaluation to "prove" f s =
  4349 r and finally gets the theorem t = r, which is again applied to the
  4350 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  4351 
  4352 * Reflection: Automatic reification now handels binding, an example is
  4353 available in src/HOL/ex/ReflectionEx.thy
  4354 
  4355 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  4356 command 'statespace' that is similar to 'record', but introduces an
  4357 abstract specification based on the locale infrastructure instead of
  4358 HOL types.  This leads to extra flexibility in composing state spaces,
  4359 in particular multiple inheritance and renaming of components.
  4360 
  4361 
  4362 *** HOL-Complex ***
  4363 
  4364 * Hyperreal: Functions root and sqrt are now defined on negative real
  4365 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  4366 Nonnegativity side conditions have been removed from many lemmas, so
  4367 that more subgoals may now be solved by simplification; potential
  4368 INCOMPATIBILITY.
  4369 
  4370 * Real: new type classes formalize real normed vector spaces and
  4371 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  4372 and norm :: 'a => real.
  4373 
  4374 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  4375 reals into other types. The overloaded constant Reals :: 'a set is now
  4376 defined as range of_real; potential INCOMPATIBILITY.
  4377 
  4378 * Real: proper support for ML code generation, including 'quickcheck'.
  4379 Reals are implemented as arbitrary precision rationals.
  4380 
  4381 * Hyperreal: Several constants that previously worked only for the
  4382 reals have been generalized, so they now work over arbitrary vector
  4383 spaces. Type annotations may need to be added in some cases; potential
  4384 INCOMPATIBILITY.
  4385 
  4386   Infinitesimal  :: ('a::real_normed_vector) star set
  4387   HFinite        :: ('a::real_normed_vector) star set
  4388   HInfinite      :: ('a::real_normed_vector) star set
  4389   approx         :: ('a::real_normed_vector) star => 'a star => bool
  4390   monad          :: ('a::real_normed_vector) star => 'a star set
  4391   galaxy         :: ('a::real_normed_vector) star => 'a star set
  4392   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  4393   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  4394   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  4395   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  4396   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  4397   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  4398   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  4399   sgn            :: 'a::real_normed_vector => 'a
  4400   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  4401 
  4402 * Complex: Some complex-specific constants are now abbreviations for
  4403 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  4404 hnorm.  Other constants have been entirely removed in favor of the
  4405 polymorphic versions (INCOMPATIBILITY):
  4406 
  4407   approx        <-- capprox
  4408   HFinite       <-- CFinite
  4409   HInfinite     <-- CInfinite
  4410   Infinitesimal <-- CInfinitesimal
  4411   monad         <-- cmonad
  4412   galaxy        <-- cgalaxy
  4413   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  4414   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  4415   (ns)deriv     <-- (ns)cderiv
  4416 
  4417 
  4418 *** HOL-Algebra ***
  4419 
  4420 * Formalisation of ideals and the quotient construction over rings.
  4421 
  4422 * Order and lattice theory no longer based on records.
  4423 INCOMPATIBILITY.
  4424 
  4425 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  4426 greatest_closed.  INCOMPATIBILITY.
  4427 
  4428 * Method algebra is now set up via an attribute.  For examples see
  4429 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  4430 of algebraic structures.
  4431 
  4432 * Renamed theory CRing to Ring.
  4433 
  4434 
  4435 *** HOL-Nominal ***
  4436 
  4437 * Substantial, yet incomplete support for nominal datatypes (binding
  4438 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  4439 src/HOL/Nominal/Examples.  Prospective users should consult
  4440 http://isabelle.in.tum.de/nominal/
  4441 
  4442 
  4443 *** ML ***
  4444 
  4445 * ML basics: just one true type int, which coincides with IntInf.int
  4446 (even on SML/NJ).
  4447 
  4448 * ML within Isar: antiquotations allow to embed statically-checked
  4449 formal entities in the source, referring to the context available at
  4450 compile-time.  For example:
  4451 
  4452 ML {* @{sort "{zero,one}"} *}
  4453 ML {* @{typ "'a => 'b"} *}
  4454 ML {* @{term "%x. x"} *}
  4455 ML {* @{prop "x == y"} *}
  4456 ML {* @{ctyp "'a => 'b"} *}
  4457 ML {* @{cterm "%x. x"} *}
  4458 ML {* @{cprop "x == y"} *}
  4459 ML {* @{thm asm_rl} *}
  4460 ML {* @{thms asm_rl} *}
  4461 ML {* @{type_name c} *}
  4462 ML {* @{type_syntax c} *}
  4463 ML {* @{const_name c} *}
  4464 ML {* @{const_syntax c} *}
  4465 ML {* @{context} *}
  4466 ML {* @{theory} *}
  4467 ML {* @{theory Pure} *}
  4468 ML {* @{theory_ref} *}
  4469 ML {* @{theory_ref Pure} *}
  4470 ML {* @{simpset} *}
  4471 ML {* @{claset} *}
  4472 ML {* @{clasimpset} *}
  4473 
  4474 The same works for sources being ``used'' within an Isar context.
  4475 
  4476 * ML in Isar: improved error reporting; extra verbosity with
  4477 ML_Context.trace enabled.
  4478 
  4479 * Pure/General/table.ML: the join operations now works via exceptions
  4480 DUP/SAME instead of type option. This is simpler in simple cases, and
  4481 admits slightly more efficient complex applications.
  4482 
  4483 * Pure: 'advanced' translation functions (parse_translation etc.) now
  4484 use Context.generic instead of just theory.
  4485 
  4486 * Pure: datatype Context.generic joins theory/Proof.context and
  4487 provides some facilities for code that works in either kind of
  4488 context, notably GenericDataFun for uniform theory and proof data.
  4489 
  4490 * Pure: simplified internal attribute type, which is now always
  4491 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  4492 local (Proof.context) attributes have been discontinued, while
  4493 minimizing code duplication. Thm.rule_attribute and
  4494 Thm.declaration_attribute build canonical attributes; see also structure
  4495 Context for further operations on Context.generic, notably
  4496 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  4497 declarations and definitions.
  4498 
  4499 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  4500 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  4501 init only required for impure data. INCOMPATIBILITY: empty really need
  4502 to be empty (no dependencies on theory content!)
  4503 
  4504 * Pure/kernel: consts certification ignores sort constraints given in
  4505 signature declarations. (This information is not relevant to the
  4506 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  4507 potential INCOMPATIBILITY.
  4508 
  4509 * Pure: axiomatic type classes are now purely definitional, with
  4510 explicit proofs of class axioms and super class relations performed
  4511 internally. See Pure/axclass.ML for the main internal interfaces --
  4512 notably AxClass.define_class supercedes AxClass.add_axclass, and
  4513 AxClass.axiomatize_class/classrel/arity supersede
  4514 Sign.add_classes/classrel/arities.
  4515 
  4516 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  4517 global/local versions on theory vs. Proof.context have been
  4518 discontinued; Attrib.syntax and Method.syntax have been adapted
  4519 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  4520 attributes, methods, etc.
  4521 
  4522 * Pure: several functions of signature "... -> theory -> theory * ..."
  4523 have been reoriented to "... -> theory -> ... * theory" in order to
  4524 allow natural usage in combination with the ||>, ||>>, |-> and
  4525 fold_map combinators.
  4526 
  4527 * Pure: official theorem names (closed derivations) and additional
  4528 comments (tags) are now strictly separate.  Name hints -- which are
  4529 maintained as tags -- may be attached any time without affecting the
  4530 derivation.
  4531 
  4532 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  4533 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  4534 achieve the old behaviour.
  4535 
  4536 * Pure: the "Goal" constant is now called "prop", supporting a
  4537 slightly more general idea of ``protecting'' meta-level rule
  4538 statements.
  4539 
  4540 * Pure: Logic.(un)varify only works in a global context, which is now
  4541 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  4542 Logic.legacy_(un)varify as temporary workaround.
  4543 
  4544 * Pure: structure Name provides scalable operations for generating
  4545 internal variable names, notably Name.variants etc.  This replaces
  4546 some popular functions from term.ML:
  4547 
  4548   Term.variant		->  Name.variant
  4549   Term.variantlist	->  Name.variant_list
  4550   Term.invent_names	->  Name.invent_list
  4551 
  4552 Note that low-level renaming rarely occurs in new code -- operations
  4553 from structure Variable are used instead (see below).
  4554 
  4555 * Pure: structure Variable provides fundamental operations for proper
  4556 treatment of fixed/schematic variables in a context.  For example,
  4557 Variable.import introduces fixes for schematics of given facts and
  4558 Variable.export reverses the effect (up to renaming) -- this replaces
  4559 various freeze_thaw operations.
  4560 
  4561 * Pure: structure Goal provides simple interfaces for
  4562 init/conclude/finish and tactical prove operations (replacing former
  4563 Tactic.prove).  Goal.prove is the canonical way to prove results
  4564 within a given context; Goal.prove_global is a degraded version for
  4565 theory level goals, including a global Drule.standard.  Note that
  4566 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  4567 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  4568 in a locale context).
  4569 
  4570 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  4571 and type checking (Syntax.check_term etc.), with common combinations
  4572 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  4573 which are considered legacy and await removal.
  4574 
  4575 * Pure/Syntax: generic interfaces for type unchecking
  4576 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  4577 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  4578 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  4579 available for convenience, but refer to the very same operations using
  4580 a mere theory instead of a full context.
  4581 
  4582 * Isar: simplified treatment of user-level errors, using exception
  4583 ERROR of string uniformly.  Function error now merely raises ERROR,
  4584 without any side effect on output channels.  The Isar toplevel takes
  4585 care of proper display of ERROR exceptions.  ML code may use plain
  4586 handle/can/try; cat_error may be used to concatenate errors like this:
  4587 
  4588   ... handle ERROR msg => cat_error msg "..."
  4589 
  4590 Toplevel ML code (run directly or through the Isar toplevel) may be
  4591 embedded into the Isar toplevel with exception display/debug like
  4592 this:
  4593 
  4594   Isar.toplevel (fn () => ...)
  4595 
  4596 INCOMPATIBILITY, removed special transform_error facilities, removed
  4597 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  4598 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  4599 -- use plain ERROR instead.
  4600 
  4601 * Isar: theory setup now has type (theory -> theory), instead of a
  4602 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  4603 
  4604 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  4605 ProofContext.debug/verbose flags.
  4606 
  4607 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  4608 theory before entering a proof state.  Transactions now always see a
  4609 quasi-functional intermediate checkpoint, both in interactive and
  4610 batch mode.
  4611 
  4612 * Isar: simplified interfaces for outer syntax.  Renamed
  4613 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  4614 OuterSyntax.add_parsers -- this functionality is now included in
  4615 OuterSyntax.command etc.  INCOMPATIBILITY.
  4616 
  4617 * Simplifier: the simpset of a running simplification process now
  4618 contains a proof context (cf. Simplifier.the_context), which is the
  4619 very context that the initial simpset has been retrieved from (by
  4620 simpset_of/local_simpset_of).  Consequently, all plug-in components
  4621 (solver, looper etc.) may depend on arbitrary proof data.
  4622 
  4623 * Simplifier.inherit_context inherits the proof context (plus the
  4624 local bounds) of the current simplification process; any simproc
  4625 etc. that calls the Simplifier recursively should do this!  Removed
  4626 former Simplifier.inherit_bounds, which is already included here --
  4627 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  4628 specify an explicit context using Simplifier.context/theory_context.
  4629 
  4630 * Simplifier/Classical Reasoner: more abstract interfaces
  4631 change_simpset/claset for modifying the simpset/claset reference of a
  4632 theory; raw versions simpset/claset_ref etc. have been discontinued --
  4633 INCOMPATIBILITY.
  4634 
  4635 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  4636 "Trueprop" etc.
  4637 
  4638 
  4639 *** System ***
  4640 
  4641 * settings: the default heap location within ISABELLE_HOME_USER now
  4642 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  4643 Isabelle installations.
  4644 
  4645 * isabelle-process: option -S (secure mode) disables some critical
  4646 operations, notably runtime compilation and evaluation of ML source
  4647 code.
  4648 
  4649 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  4650 
  4651 * Support for parallel execution, using native multicore support of
  4652 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  4653 independent theories, according to the given theory header
  4654 specifications. The maximum number of worker threads is specified via
  4655 usedir option -M or the "max-threads" setting in Proof General. A
  4656 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  4657 to 6 on a 8-core machine.  User-code needs to observe certain
  4658 guidelines for thread-safe programming, see appendix A in the Isar
  4659 Implementation manual.
  4660 
  4661 
  4662 
  4663 New in Isabelle2005 (October 2005)
  4664 ----------------------------------
  4665 
  4666 *** General ***
  4667 
  4668 * Theory headers: the new header syntax for Isar theories is
  4669 
  4670   theory <name>
  4671   imports <theory1> ... <theoryN>
  4672   uses <file1> ... <fileM>
  4673   begin
  4674 
  4675 where the 'uses' part is optional.  The previous syntax
  4676 
  4677   theory <name> = <theory1> + ... + <theoryN>:
  4678 
  4679 will disappear in the next release.  Use isatool fixheaders to convert
  4680 existing theory files.  Note that there is no change in ancient
  4681 non-Isar theories now, but these will disappear soon.
  4682 
  4683 * Theory loader: parent theories can now also be referred to via
  4684 relative and absolute paths.
  4685 
  4686 * Command 'find_theorems' searches for a list of criteria instead of a
  4687 list of constants. Known criteria are: intro, elim, dest, name:string,
  4688 simp:term, and any term. Criteria can be preceded by '-' to select
  4689 theorems that do not match. Intro, elim, dest select theorems that
  4690 match the current goal, name:s selects theorems whose fully qualified
  4691 name contain s, and simp:term selects all simplification rules whose
  4692 lhs match term.  Any other term is interpreted as pattern and selects
  4693 all theorems matching the pattern. Available in ProofGeneral under
  4694 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  4695 
  4696   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  4697 
  4698 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  4699 matching the current goal as introduction rule and not having "HOL."
  4700 in their name (i.e. not being defined in theory HOL).
  4701 
  4702 * Command 'thms_containing' has been discontinued in favour of
  4703 'find_theorems'; INCOMPATIBILITY.
  4704 
  4705 * Communication with Proof General is now 8bit clean, which means that
  4706 Unicode text in UTF-8 encoding may be used within theory texts (both
  4707 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4708 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4709 
  4710   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4711   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4712 
  4713 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4714 Classical Reasoner.  Typical big applications run around 2 times
  4715 faster.
  4716 
  4717 
  4718 *** Document preparation ***
  4719 
  4720 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4721 of raw sources.  Only those symbols that do not require additional
  4722 LaTeX packages (depending on comments in isabellesym.sty) are
  4723 displayed properly, everything else is left verbatim.  isatool display
  4724 and isatool print are used as front ends (these are subject to the
  4725 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4726 
  4727 * Command tags control specific markup of certain regions of text,
  4728 notably folding and hiding.  Predefined tags include "theory" (for
  4729 theory begin and end), "proof" for proof commands, and "ML" for
  4730 commands involving ML code; the additional tags "visible" and
  4731 "invisible" are unused by default.  Users may give explicit tag
  4732 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4733 interpretation of tags is determined by the LaTeX job during document
  4734 preparation: see option -V of isatool usedir, or options -n and -t of
  4735 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4736 \isadroptag.
  4737 
  4738 Several document versions may be produced at the same time via isatool
  4739 usedir (the generated index.html will link all of them).  Typical
  4740 specifications include ''-V document=theory,proof,ML'' to present
  4741 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4742 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4743 these parts without any formal replacement text.  The Isabelle site
  4744 default settings produce ''document'' and ''outline'' versions as
  4745 specified above.
  4746 
  4747 * Several new antiquotations:
  4748 
  4749   @{term_type term} prints a term with its type annotated;
  4750 
  4751   @{typeof term} prints the type of a term;
  4752 
  4753   @{const const} is the same as @{term const}, but checks that the
  4754   argument is a known logical constant;
  4755 
  4756   @{term_style style term} and @{thm_style style thm} print a term or
  4757   theorem applying a "style" to it
  4758 
  4759   @{ML text}
  4760 
  4761 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4762 definitions, equations, inequations etc., 'concl' printing only the
  4763 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4764 to print the specified premise.  TermStyle.add_style provides an ML
  4765 interface for introducing further styles.  See also the "LaTeX Sugar"
  4766 document practical applications.  The ML antiquotation prints
  4767 type-checked ML expressions verbatim.
  4768 
  4769 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4770 and 'text' support optional locale specification '(in loc)', which
  4771 specifies the default context for interpreting antiquotations.  For
  4772 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4773 
  4774 * Option 'locale=NAME' of antiquotations specifies an alternative
  4775 context interpreting the subsequent argument.  For example: @{thm
  4776 [locale=lattice] inf_assoc}.
  4777 
  4778 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4779 a proof context.
  4780 
  4781 * Proper output of antiquotations for theory commands involving a
  4782 proof context (such as 'locale' or 'theorem (in loc) ...').
  4783 
  4784 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4785 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4786 
  4787 * isatool usedir: new option -C (default true) controls whether option
  4788 -D should include a copy of the original document directory; -C false
  4789 prevents unwanted effects such as copying of administrative CVS data.
  4790 
  4791 
  4792 *** Pure ***
  4793 
  4794 * Considerably improved version of 'constdefs' command.  Now performs
  4795 automatic type-inference of declared constants; additional support for
  4796 local structure declarations (cf. locales and HOL records), see also
  4797 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4798 sequential dependencies of definitions within a single 'constdefs'
  4799 section; moreover, the declared name needs to be an identifier.  If
  4800 all fails, consider to fall back on 'consts' and 'defs' separately.
  4801 
  4802 * Improved indexed syntax and implicit structures.  First of all,
  4803 indexed syntax provides a notational device for subscripted
  4804 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4805 expressions.  Secondly, in a local context with structure
  4806 declarations, number indexes \<^sub>n or the empty index (default
  4807 number 1) refer to a certain fixed variable implicitly; option
  4808 show_structs controls printing of implicit structures.  Typical
  4809 applications of these concepts involve record types and locales.
  4810 
  4811 * New command 'no_syntax' removes grammar declarations (and
  4812 translations) resulting from the given syntax specification, which is
  4813 interpreted in the same manner as for the 'syntax' command.
  4814 
  4815 * 'Advanced' translation functions (parse_translation etc.) may depend
  4816 on the signature of the theory context being presently used for
  4817 parsing/printing, see also isar-ref manual.
  4818 
  4819 * Improved 'oracle' command provides a type-safe interface to turn an
  4820 ML expression of type theory -> T -> term into a primitive rule of
  4821 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4822 is already included here); see also FOL/ex/IffExample.thy;
  4823 INCOMPATIBILITY.
  4824 
  4825 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4826 before); "cI" is no longer bound, use "c.intro" instead.
  4827 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4828 axclasses vs. locales.
  4829 
  4830 * Improved internal renaming of symbolic identifiers -- attach primes
  4831 instead of base 26 numbers.
  4832 
  4833 * New flag show_question_marks controls printing of leading question
  4834 marks in schematic variable names.
  4835 
  4836 * In schematic variable names, *any* symbol following \<^isub> or
  4837 \<^isup> is now treated as part of the base name.  For example, the
  4838 following works without printing of awkward ".0" indexes:
  4839 
  4840   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4841     by simp
  4842 
  4843 * Inner syntax includes (*(*nested*) comments*).
  4844 
  4845 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4846 annotations as "(00...)".
  4847 
  4848 * Clear separation of logical types and nonterminals, where the latter
  4849 may only occur in 'syntax' specifications or type abbreviations.
  4850 Before that distinction was only partially implemented via type class
  4851 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4852 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4853 exotic syntax specifications may require further adaption
  4854 (e.g. Cube/Cube.thy).
  4855 
  4856 * Removed obsolete type class "logic", use the top sort {} instead.
  4857 Note that non-logical types should be declared as 'nonterminals'
  4858 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4859 specifications.
  4860 
  4861 * Attributes 'induct' and 'cases': type or set names may now be
  4862 locally fixed variables as well.
  4863 
  4864 * Simplifier: can now control the depth to which conditional rewriting
  4865 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4866 Limit.
  4867 
  4868 * Simplifier: simplification procedures may now take the current
  4869 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4870 interface), which is very useful for calling the Simplifier
  4871 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4872 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4873 low-level mk_simproc no longer applies Logic.varify internally, to
  4874 allow for use in a context of fixed variables.
  4875 
  4876 * thin_tac now works even if the assumption being deleted contains !!
  4877 or ==>.  More generally, erule now works even if the major premise of
  4878 the elimination rule contains !! or ==>.
  4879 
  4880 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4881 
  4882 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4883 from Pure, which contains all common declarations already.  Both
  4884 theories are defined via plain Isabelle/Isar .thy files.
  4885 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4886 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4887 use isatool fixcpure to adapt your theory and ML sources.
  4888 
  4889 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4890 selections of theorems in named facts via index ranges.
  4891 
  4892 * 'print_theorems': in theory mode, really print the difference
  4893 wrt. the last state (works for interactive theory development only),
  4894 in proof mode print all local facts (cf. 'print_facts');
  4895 
  4896 * 'hide': option '(open)' hides only base names.
  4897 
  4898 * More efficient treatment of intermediate checkpoints in interactive
  4899 theory development.
  4900 
  4901 * Code generator is now invoked via code_module (incremental code
  4902 generation) and code_library (modular code generation, ML structures
  4903 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4904 must be quoted when used as identifiers.
  4905 
  4906 * New 'value' command for reading, evaluating and printing terms using
  4907 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4908 quoted when used as identifier.
  4909 
  4910 
  4911 *** Locales ***
  4912 
  4913 * New commands for the interpretation of locale expressions in
  4914 theories (1), locales (2) and proof contexts (3).  These generate
  4915 proof obligations from the expression specification.  After the
  4916 obligations have been discharged, theorems of the expression are added
  4917 to the theory, target locale or proof context.  The synopsis of the
  4918 commands is a follows:
  4919 
  4920   (1) interpretation expr inst
  4921   (2) interpretation target < expr
  4922   (3) interpret expr inst
  4923 
  4924 Interpretation in theories and proof contexts require a parameter
  4925 instantiation of terms from the current context.  This is applied to
  4926 specifications and theorems of the interpreted expression.
  4927 Interpretation in locales only permits parameter renaming through the
  4928 locale expression.  Interpretation is smart in that interpretations
  4929 that are active already do not occur in proof obligations, neither are
  4930 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4931 inspect active interpretations of a particular locale.  For details,
  4932 see the Isar Reference manual.  Examples can be found in
  4933 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4934 
  4935 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4936 'interpret' instead.
  4937 
  4938 * New context element 'constrains' for adding type constraints to
  4939 parameters.
  4940 
  4941 * Context expressions: renaming of parameters with syntax
  4942 redeclaration.
  4943 
  4944 * Locale declaration: 'includes' disallowed.
  4945 
  4946 * Proper static binding of attribute syntax -- i.e. types / terms /
  4947 facts mentioned as arguments are always those of the locale definition
  4948 context, independently of the context of later invocations.  Moreover,
  4949 locale operations (renaming and type / term instantiation) are applied
  4950 to attribute arguments as expected.
  4951 
  4952 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4953 actual attributes; rare situations may require Attrib.attribute to
  4954 embed those attributes into Attrib.src that lack concrete syntax.
  4955 Attribute implementations need to cooperate properly with the static
  4956 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4957 Attrib.XXX_thm etc. already do the right thing without further
  4958 intervention.  Only unusual applications -- such as "where" or "of"
  4959 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4960 on the context and the facts involved -- may have to assign parsed
  4961 values to argument tokens explicitly.
  4962 
  4963 * Changed parameter management in theorem generation for long goal
  4964 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4965 theorem statement in rare situations.
  4966 
  4967 * Locale inspection command 'print_locale' omits notes elements.  Use
  4968 'print_locale!' to have them included in the output.
  4969 
  4970 
  4971 *** Provers ***
  4972 
  4973 * Provers/hypsubst.ML: improved version of the subst method, for
  4974 single-step rewriting: it now works in bound variable contexts. New is
  4975 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  4976 rewrite a different subterm than the original subst method, which is
  4977 still available as 'simplesubst'.
  4978 
  4979 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  4980 and quasi orders.
  4981 
  4982 * Provers/trancl.ML: new transitivity reasoner for transitive and
  4983 reflexive-transitive closure of relations.
  4984 
  4985 * Provers/blast.ML: new reference depth_limit to make blast's depth
  4986 limit (previously hard-coded with a value of 20) user-definable.
  4987 
  4988 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  4989 is peformed already.  Object-logics merely need to finish their
  4990 initial simpset configuration as before.  INCOMPATIBILITY.
  4991 
  4992 
  4993 *** HOL ***
  4994 
  4995 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  4996 
  4997   syntax (epsilon)
  4998     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  4999 
  5000 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  5001 and x-symbol; use option '-m epsilon' to get it actually printed.
  5002 Moreover, the mathematically important symbolic identifier \<epsilon>
  5003 becomes available as variable, constant etc.  INCOMPATIBILITY,
  5004 
  5005 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  5006 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  5007 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  5008 support corresponding Isar calculations.
  5009 
  5010 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  5011 instead of ":".
  5012 
  5013 * theory SetInterval: changed the syntax for open intervals:
  5014 
  5015   Old       New
  5016   {..n(}    {..<n}
  5017   {)n..}    {n<..}
  5018   {m..n(}   {m..<n}
  5019   {)m..n}   {m<..n}
  5020   {)m..n(}  {m<..<n}
  5021 
  5022 The old syntax is still supported but will disappear in the next
  5023 release.  For conversion use the following Emacs search and replace
  5024 patterns (these are not perfect but work quite well):
  5025 
  5026   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  5027   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  5028 
  5029 * Theory Commutative_Ring (in Library): method comm_ring for proving
  5030 equalities in commutative rings; method 'algebra' provides a generic
  5031 interface.
  5032 
  5033 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  5034 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  5035 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  5036 be a tuple pattern.
  5037 
  5038 Some new syntax forms are available:
  5039 
  5040   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  5041   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  5042   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  5043   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  5044 
  5045 The latter form "\<Sum>x < k. e" used to be based on a separate
  5046 function "Summation", which has been discontinued.
  5047 
  5048 * theory Finite_Set: in structured induction proofs, the insert case
  5049 is now 'case (insert x F)' instead of the old counterintuitive 'case
  5050 (insert F x)'.
  5051 
  5052 * The 'refute' command has been extended to support a much larger
  5053 fragment of HOL, including axiomatic type classes, constdefs and
  5054 typedefs, inductive datatypes and recursion.
  5055 
  5056 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  5057 Requires zChaff with proof generation to be installed.  See
  5058 HOL/ex/SAT_Examples.thy for examples.
  5059 
  5060 * Datatype induction via method 'induct' now preserves the name of the
  5061 induction variable. For example, when proving P(xs::'a list) by
  5062 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  5063 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  5064 in unstructured proof scripts.
  5065 
  5066 * Reworked implementation of records.  Improved scalability for
  5067 records with many fields, avoiding performance problems for type
  5068 inference. Records are no longer composed of nested field types, but
  5069 of nested extension types. Therefore the record type only grows linear
  5070 in the number of extensions and not in the number of fields.  The
  5071 top-level (users) view on records is preserved.  Potential
  5072 INCOMPATIBILITY only in strange cases, where the theory depends on the
  5073 old record representation. The type generated for a record is called
  5074 <record_name>_ext_type.
  5075 
  5076 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  5077 proofs triggered by a record definition or a simproc (if
  5078 quick_and_dirty is enabled).  Definitions of large records can take
  5079 quite long.
  5080 
  5081 New simproc record_upd_simproc for simplification of multiple record
  5082 updates enabled by default.  Moreover, trivial updates are also
  5083 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  5084 occasionally, since simplification is more powerful by default.
  5085 
  5086 * typedef: proper support for polymorphic sets, which contain extra
  5087 type-variables in the term.
  5088 
  5089 * Simplifier: automatically reasons about transitivity chains
  5090 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  5091 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  5092 old proofs break occasionally as simplification may now solve more
  5093 goals than previously.
  5094 
  5095 * Simplifier: converts x <= y into x = y if assumption y <= x is
  5096 present.  Works for all partial orders (class "order"), in particular
  5097 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  5098 just like y <= x.
  5099 
  5100 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  5101 bound variable or a constant then the let is unfolded.  Otherwise
  5102 first a is simplified to b, and then f b is simplified to g. If
  5103 possible we abstract b from g arriving at "let x = b in h x",
  5104 otherwise we unfold the let and arrive at g.  The simproc can be
  5105 enabled/disabled by the reference use_let_simproc.  Potential
  5106 INCOMPATIBILITY since simplification is more powerful by default.
  5107 
  5108 * Classical reasoning: the meson method now accepts theorems as arguments.
  5109 
  5110 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  5111 jobs to provide advice on the provability of subgoals.
  5112 
  5113 * Theory OrderedGroup and Ring_and_Field: various additions and
  5114 improvements to faciliate calculations involving equalities and
  5115 inequalities.
  5116 
  5117 The following theorems have been eliminated or modified
  5118 (INCOMPATIBILITY):
  5119 
  5120   abs_eq             now named abs_of_nonneg
  5121   abs_of_ge_0        now named abs_of_nonneg
  5122   abs_minus_eq       now named abs_of_nonpos
  5123   imp_abs_id         now named abs_of_nonneg
  5124   imp_abs_neg_id     now named abs_of_nonpos
  5125   mult_pos           now named mult_pos_pos
  5126   mult_pos_le        now named mult_nonneg_nonneg
  5127   mult_pos_neg_le    now named mult_nonneg_nonpos
  5128   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  5129   mult_neg           now named mult_neg_neg
  5130   mult_neg_le        now named mult_nonpos_nonpos
  5131 
  5132 * The following lemmas in Ring_and_Field have been added to the simplifier:
  5133      
  5134      zero_le_square
  5135      not_square_less_zero 
  5136 
  5137   The following lemmas have been deleted from Real/RealPow:
  5138   
  5139      realpow_zero_zero
  5140      realpow_two
  5141      realpow_less
  5142      zero_le_power
  5143      realpow_two_le
  5144      abs_realpow_two
  5145      realpow_two_abs     
  5146 
  5147 * Theory Parity: added rules for simplifying exponents.
  5148 
  5149 * Theory List:
  5150 
  5151 The following theorems have been eliminated or modified
  5152 (INCOMPATIBILITY):
  5153 
  5154   list_all_Nil       now named list_all.simps(1)
  5155   list_all_Cons      now named list_all.simps(2)
  5156   list_all_conv      now named list_all_iff
  5157   set_mem_eq         now named mem_iff
  5158 
  5159 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  5160 asymptotic "big O" calculations.  See the notes in BigO.thy.
  5161 
  5162 
  5163 *** HOL-Complex ***
  5164 
  5165 * Theory RealDef: better support for embedding natural numbers and
  5166 integers in the reals.
  5167 
  5168 The following theorems have been eliminated or modified
  5169 (INCOMPATIBILITY):
  5170 
  5171   exp_ge_add_one_self  now requires no hypotheses
  5172   real_of_int_add      reversed direction of equality (use [symmetric])
  5173   real_of_int_minus    reversed direction of equality (use [symmetric])
  5174   real_of_int_diff     reversed direction of equality (use [symmetric])
  5175   real_of_int_mult     reversed direction of equality (use [symmetric])
  5176 
  5177 * Theory RComplete: expanded support for floor and ceiling functions.
  5178 
  5179 * Theory Ln is new, with properties of the natural logarithm
  5180 
  5181 * Hyperreal: There is a new type constructor "star" for making
  5182 nonstandard types.  The old type names are now type synonyms:
  5183 
  5184   hypreal = real star
  5185   hypnat = nat star
  5186   hcomplex = complex star
  5187 
  5188 * Hyperreal: Many groups of similarly-defined constants have been
  5189 replaced by polymorphic versions (INCOMPATIBILITY):
  5190 
  5191   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  5192 
  5193   starset      <-- starsetNat, starsetC
  5194   *s*          <-- *sNat*, *sc*
  5195   starset_n    <-- starsetNat_n, starsetC_n
  5196   *sn*         <-- *sNatn*, *scn*
  5197   InternalSets <-- InternalNatSets, InternalCSets
  5198 
  5199   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  5200   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  5201   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  5202   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  5203   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  5204 
  5205 * Hyperreal: Many type-specific theorems have been removed in favor of
  5206 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  5207 
  5208   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  5209   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  5210   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  5211   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  5212   right_minus <-- hypreal_add_minus
  5213   left_minus <-- {hypreal,hcomplex}_add_minus_left
  5214   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  5215   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  5216   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  5217   mult_1_right <-- hcomplex_mult_one_right
  5218   mult_zero_left <-- hcomplex_mult_zero_left
  5219   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  5220   right_distrib <-- hypnat_add_mult_distrib2
  5221   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  5222   right_inverse <-- hypreal_mult_inverse
  5223   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  5224   order_refl <-- {hypreal,hypnat}_le_refl
  5225   order_trans <-- {hypreal,hypnat}_le_trans
  5226   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  5227   order_less_le <-- {hypreal,hypnat}_less_le
  5228   linorder_linear <-- {hypreal,hypnat}_le_linear
  5229   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  5230   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  5231   add_nonneg_nonneg <-- hypreal_le_add_order
  5232 
  5233 * Hyperreal: Separate theorems having to do with type-specific
  5234 versions of constants have been merged into theorems that apply to the
  5235 new polymorphic constants (INCOMPATIBILITY):
  5236 
  5237   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  5238   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  5239   STAR_Un <-- {STAR,NatStar,STARC}_Un
  5240   STAR_Int <-- {STAR,NatStar,STARC}_Int
  5241   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  5242   STAR_subset <-- {STAR,NatStar,STARC}_subset
  5243   STAR_mem <-- {STAR,NatStar,STARC}_mem
  5244   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  5245   STAR_diff <-- {STAR,STARC}_diff
  5246   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  5247     STARC_hcomplex_of_complex}_image_subset
  5248   starset_n_Un <-- starset{Nat,C}_n_Un
  5249   starset_n_Int <-- starset{Nat,C}_n_Int
  5250   starset_n_Compl <-- starset{Nat,C}_n_Compl
  5251   starset_n_diff <-- starset{Nat,C}_n_diff
  5252   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  5253   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  5254   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  5255   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  5256   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  5257   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  5258   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  5259   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  5260   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  5261   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  5262   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  5263   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  5264   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  5265   starfun_diff <-- starfun{C,RC,CR}_diff
  5266   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  5267   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  5268   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  5269   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  5270   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  5271   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  5272   starfun_Id <-- starfunC_Id
  5273   starfun_approx <-- starfun{Nat,CR}_approx
  5274   starfun_capprox <-- starfun{C,RC}_capprox
  5275   starfun_abs <-- starfunNat_rabs
  5276   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  5277   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  5278   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  5279   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  5280   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  5281   starfun_add_approx <-- starfunCR_add_approx
  5282   starfun_inverse_inverse <-- starfunC_inverse_inverse
  5283   starfun_divide <-- starfun{C,CR,RC}_divide
  5284   starfun_n <-- starfun{Nat,C}_n
  5285   starfun_n_mult <-- starfun{Nat,C}_n_mult
  5286   starfun_n_add <-- starfun{Nat,C}_n_add
  5287   starfun_n_add_minus <-- starfunNat_n_add_minus
  5288   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  5289   starfun_n_minus <-- starfun{Nat,C}_n_minus
  5290   starfun_n_eq <-- starfun{Nat,C}_n_eq
  5291 
  5292   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  5293   star_n_minus <-- {hypreal,hcomplex}_minus
  5294   star_n_diff <-- {hypreal,hcomplex}_diff
  5295   star_n_mult <-- {hypreal,hcomplex}_mult
  5296   star_n_inverse <-- {hypreal,hcomplex}_inverse
  5297   star_n_le <-- {hypreal,hypnat}_le
  5298   star_n_less <-- {hypreal,hypnat}_less
  5299   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  5300   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  5301   star_n_abs <-- hypreal_hrabs
  5302   star_n_divide <-- hcomplex_divide
  5303 
  5304   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  5305   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  5306   star_of_diff <-- hypreal_of_real_diff
  5307   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  5308   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  5309   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  5310   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  5311   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  5312   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  5313   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  5314   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  5315   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  5316   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  5317   star_of_number_of <-- {hypreal,hcomplex}_number_of
  5318   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  5319   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  5320   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  5321   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  5322   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  5323   star_of_power <-- hypreal_of_real_power
  5324   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  5325 
  5326 * Hyperreal: new method "transfer" that implements the transfer
  5327 principle of nonstandard analysis. With a subgoal that mentions
  5328 nonstandard types like "'a star", the command "apply transfer"
  5329 replaces it with an equivalent one that mentions only standard types.
  5330 To be successful, all free variables must have standard types; non-
  5331 standard variables must have explicit universal quantifiers.
  5332 
  5333 * Hyperreal: A theory of Taylor series.
  5334 
  5335 
  5336 *** HOLCF ***
  5337 
  5338 * Discontinued special version of 'constdefs' (which used to support
  5339 continuous functions) in favor of the general Pure one with full
  5340 type-inference.
  5341 
  5342 * New simplification procedure for solving continuity conditions; it
  5343 is much faster on terms with many nested lambda abstractions (cubic
  5344 instead of exponential time).
  5345 
  5346 * New syntax for domain package: selector names are now optional.
  5347 Parentheses should be omitted unless argument is lazy, for example:
  5348 
  5349   domain 'a stream = cons "'a" (lazy "'a stream")
  5350 
  5351 * New command 'fixrec' for defining recursive functions with pattern
  5352 matching; defining multiple functions with mutual recursion is also
  5353 supported.  Patterns may include the constants cpair, spair, up, sinl,
  5354 sinr, or any data constructor defined by the domain package. The given
  5355 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  5356 syntax and examples.
  5357 
  5358 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  5359 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  5360 but the proof obligation additionally includes an admissibility
  5361 requirement. The packages generate instances of class cpo or pcpo,
  5362 with continuity and strictness theorems for Rep and Abs.
  5363 
  5364 * HOLCF: Many theorems have been renamed according to a more standard naming
  5365 scheme (INCOMPATIBILITY):
  5366 
  5367   foo_inject:  "foo$x = foo$y ==> x = y"
  5368   foo_eq:      "(foo$x = foo$y) = (x = y)"
  5369   foo_less:    "(foo$x << foo$y) = (x << y)"
  5370   foo_strict:  "foo$UU = UU"
  5371   foo_defined: "... ==> foo$x ~= UU"
  5372   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  5373 
  5374 
  5375 *** ZF ***
  5376 
  5377 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  5378 including the First Isomorphism Theorem (on quotienting by the kernel
  5379 of a homomorphism).
  5380 
  5381 * ZF/Simplifier: install second copy of type solver that actually
  5382 makes use of TC rules declared to Isar proof contexts (or locales);
  5383 the old version is still required for ML proof scripts.
  5384 
  5385 
  5386 *** Cube ***
  5387 
  5388 * Converted to Isar theory format; use locales instead of axiomatic
  5389 theories.
  5390 
  5391 
  5392 *** ML ***
  5393 
  5394 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  5395 for ||>, ||>>, |>>,
  5396 
  5397 * Pure/library.ML no longer defines its own option datatype, but uses
  5398 that of the SML basis, which has constructors NONE and SOME instead of
  5399 None and Some, as well as exception Option.Option instead of OPTION.
  5400 The functions the, if_none, is_some, is_none have been adapted
  5401 accordingly, while Option.map replaces apsome.
  5402 
  5403 * Pure/library.ML: the exception LIST has been given up in favour of
  5404 the standard exceptions Empty and Subscript, as well as
  5405 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  5406 superceded by the standard hd and tl functions etc.
  5407 
  5408 A number of basic list functions are no longer exported to the ML
  5409 toplevel, as they are variants of predefined functions.  The following
  5410 suggests how one can translate existing code:
  5411 
  5412     rev_append xs ys = List.revAppend (xs, ys)
  5413     nth_elem (i, xs) = List.nth (xs, i)
  5414     last_elem xs = List.last xs
  5415     flat xss = List.concat xss
  5416     seq fs = List.app fs
  5417     partition P xs = List.partition P xs
  5418     mapfilter f xs = List.mapPartial f xs
  5419 
  5420 * Pure/library.ML: several combinators for linear functional
  5421 transformations, notably reverse application and composition:
  5422 
  5423   x |> f                f #> g
  5424   (x, y) |-> f          f #-> g
  5425 
  5426 * Pure/library.ML: introduced/changed precedence of infix operators:
  5427 
  5428   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  5429   infix 2 ?;
  5430   infix 3 o oo ooo oooo;
  5431   infix 4 ~~ upto downto;
  5432 
  5433 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  5434 infix operators.
  5435 
  5436 * Pure/library.ML: natural list combinators fold, fold_rev, and
  5437 fold_map support linear functional transformations and nesting.  For
  5438 example:
  5439 
  5440   fold f [x1, ..., xN] y =
  5441     y |> f x1 |> ... |> f xN
  5442 
  5443   (fold o fold) f [xs1, ..., xsN] y =
  5444     y |> fold f xs1 |> ... |> fold f xsN
  5445 
  5446   fold f [x1, ..., xN] =
  5447     f x1 #> ... #> f xN
  5448 
  5449   (fold o fold) f [xs1, ..., xsN] =
  5450     fold f xs1 #> ... #> fold f xsN
  5451 
  5452 * Pure/library.ML: the following selectors on type 'a option are
  5453 available:
  5454 
  5455   the:               'a option -> 'a  (*partial*)
  5456   these:             'a option -> 'a  where 'a = 'b list
  5457   the_default: 'a -> 'a option -> 'a
  5458   the_list:          'a option -> 'a list
  5459 
  5460 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5461 basic operations for association lists, following natural argument
  5462 order; moreover the explicit equality predicate passed here avoids
  5463 potentially expensive polymorphic runtime equality checks.
  5464 The old functions may be expressed as follows:
  5465 
  5466   assoc = uncurry (AList.lookup (op =))
  5467   assocs = these oo AList.lookup (op =)
  5468   overwrite = uncurry (AList.update (op =)) o swap
  5469 
  5470 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5471 
  5472   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  5473   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  5474 
  5475 replacing make_keylist and keyfilter (occassionally used)
  5476 Naive rewrites:
  5477 
  5478   make_keylist = AList.make
  5479   keyfilter = AList.find (op =)
  5480 
  5481 * eq_fst and eq_snd now take explicit equality parameter, thus
  5482   avoiding eqtypes. Naive rewrites:
  5483 
  5484     eq_fst = eq_fst (op =)
  5485     eq_snd = eq_snd (op =)
  5486 
  5487 * Removed deprecated apl and apr (rarely used).
  5488   Naive rewrites:
  5489 
  5490     apl (n, op) =>>= curry op n
  5491     apr (op, m) =>>= fn n => op (n, m)
  5492 
  5493 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  5494 provides a reasonably efficient light-weight implementation of sets as
  5495 lists.
  5496 
  5497 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  5498 few new operations; existing lookup and update are now curried to
  5499 follow natural argument order (for use with fold etc.);
  5500 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  5501 
  5502 * Pure/General: output via the Isabelle channels of
  5503 writeln/warning/error etc. is now passed through Output.output, with a
  5504 hook for arbitrary transformations depending on the print_mode
  5505 (cf. Output.add_mode -- the first active mode that provides a output
  5506 function wins).  Already formatted output may be embedded into further
  5507 text via Output.raw; the result of Pretty.string_of/str_of and derived
  5508 functions (string_of_term/cterm/thm etc.) is already marked raw to
  5509 accommodate easy composition of diagnostic messages etc.  Programmers
  5510 rarely need to care about Output.output or Output.raw at all, with
  5511 some notable exceptions: Output.output is required when bypassing the
  5512 standard channels (writeln etc.), or in token translations to produce
  5513 properly formatted results; Output.raw is required when capturing
  5514 already output material that will eventually be presented to the user
  5515 a second time.  For the default print mode, both Output.output and
  5516 Output.raw have no effect.
  5517 
  5518 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  5519 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  5520 cumulative results are displayed at the end of a batch session.
  5521 
  5522 * Pure/General: File.sysify_path and File.quote_sysify path have been
  5523 replaced by File.platform_path and File.shell_path (with appropriate
  5524 hooks).  This provides a clean interface for unusual systems where the
  5525 internal and external process view of file names are different.
  5526 
  5527 * Pure: more efficient orders for basic syntactic entities: added
  5528 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  5529 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  5530 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  5531 orders now -- potential INCOMPATIBILITY for code that depends on a
  5532 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  5533 Library.sort_strings on result).
  5534 
  5535 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  5536 fold_types traverse types/terms from left to right, observing natural
  5537 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  5538 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  5539 
  5540 * Pure: name spaces have been refined, with significant changes of the
  5541 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  5542 to extern(_table).  The plain name entry path is superceded by a
  5543 general 'naming' context, which also includes the 'policy' to produce
  5544 a fully qualified name and external accesses of a fully qualified
  5545 name; NameSpace.extend is superceded by context dependent
  5546 Sign.declare_name.  Several theory and proof context operations modify
  5547 the naming context.  Especially note Theory.restore_naming and
  5548 ProofContext.restore_naming to get back to a sane state; note that
  5549 Theory.add_path is no longer sufficient to recover from
  5550 Theory.absolute_path in particular.
  5551 
  5552 * Pure: new flags short_names (default false) and unique_names
  5553 (default true) for controlling output of qualified names.  If
  5554 short_names is set, names are printed unqualified.  If unique_names is
  5555 reset, the name prefix is reduced to the minimum required to achieve
  5556 the original result when interning again, even if there is an overlap
  5557 with earlier declarations.
  5558 
  5559 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  5560 now 'extend', and 'merge' gets an additional Pretty.pp argument
  5561 (useful for printing error messages).  INCOMPATIBILITY.
  5562 
  5563 * Pure: major reorganization of the theory context.  Type Sign.sg and
  5564 Theory.theory are now identified, referring to the universal
  5565 Context.theory (see Pure/context.ML).  Actual signature and theory
  5566 content is managed as theory data.  The old code and interfaces were
  5567 spread over many files and structures; the new arrangement introduces
  5568 considerable INCOMPATIBILITY to gain more clarity:
  5569 
  5570   Context -- theory management operations (name, identity, inclusion,
  5571     parents, ancestors, merge, etc.), plus generic theory data;
  5572 
  5573   Sign -- logical signature and syntax operations (declaring consts,
  5574     types, etc.), plus certify/read for common entities;
  5575 
  5576   Theory -- logical theory operations (stating axioms, definitions,
  5577     oracles), plus a copy of logical signature operations (consts,
  5578     types, etc.); also a few basic management operations (Theory.copy,
  5579     Theory.merge, etc.)
  5580 
  5581 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  5582 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  5583 for convenience -- they merely return the theory.
  5584 
  5585 * Pure: type Type.tsig is superceded by theory in most interfaces.
  5586 
  5587 * Pure: the Isar proof context type is already defined early in Pure
  5588 as Context.proof (note that ProofContext.context and Proof.context are
  5589 aliases, where the latter is the preferred name).  This enables other
  5590 Isabelle components to refer to that type even before Isar is present.
  5591 
  5592 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  5593 typeK, constK, axiomK, oracleK), but provide explicit operations for
  5594 any of these kinds.  For example, Sign.intern typeK is now
  5595 Sign.intern_type, Theory.hide_space Sign.typeK is now
  5596 Theory.hide_types.  Also note that former
  5597 Theory.hide_classes/types/consts are now
  5598 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  5599 internalize their arguments!  INCOMPATIBILITY.
  5600 
  5601 * Pure: get_thm interface (of PureThy and ProofContext) expects
  5602 datatype thmref (with constructors Name and NameSelection) instead of
  5603 plain string -- INCOMPATIBILITY;
  5604 
  5605 * Pure: cases produced by proof methods specify options, where NONE
  5606 means to remove case bindings -- INCOMPATIBILITY in
  5607 (RAW_)METHOD_CASES.
  5608 
  5609 * Pure: the following operations retrieve axioms or theorems from a
  5610 theory node or theory hierarchy, respectively:
  5611 
  5612   Theory.axioms_of: theory -> (string * term) list
  5613   Theory.all_axioms_of: theory -> (string * term) list
  5614   PureThy.thms_of: theory -> (string * thm) list
  5615   PureThy.all_thms_of: theory -> (string * thm) list
  5616 
  5617 * Pure: print_tac now outputs the goal through the trace channel.
  5618 
  5619 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  5620 Reference Toplevel.debug (default false) controls detailed printing
  5621 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  5622 controls execution profiling -- set to 1 for time and 2 for space
  5623 (both increase the runtime).
  5624 
  5625 * Isar session: The initial use of ROOT.ML is now always timed,
  5626 i.e. the log will show the actual process times, in contrast to the
  5627 elapsed wall-clock time that the outer shell wrapper produces.
  5628 
  5629 * Simplifier: improved handling of bound variables (nameless
  5630 representation, avoid allocating new strings).  Simprocs that invoke
  5631 the Simplifier recursively should use Simplifier.inherit_bounds to
  5632 avoid local name clashes.  Failure to do so produces warnings
  5633 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  5634 for further details.
  5635 
  5636 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  5637 bindings for all theorems stored within a given theory; this may help
  5638 in porting non-Isar theories to Isar ones, while keeping ML proof
  5639 scripts for the time being.
  5640 
  5641 * ML operator HTML.with_charset specifies the charset begin used for
  5642 generated HTML files.  For example:
  5643 
  5644   HTML.with_charset "utf-8" use_thy "Hebrew";
  5645   HTML.with_charset "utf-8" use_thy "Chinese";
  5646 
  5647 
  5648 *** System ***
  5649 
  5650 * Allow symlinks to all proper Isabelle executables (Isabelle,
  5651 isabelle, isatool etc.).
  5652 
  5653 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  5654 isatool doc, isatool mkdir, display_drafts etc.).
  5655 
  5656 * isatool usedir: option -f allows specification of the ML file to be
  5657 used by Isabelle; default is ROOT.ML.
  5658 
  5659 * New isatool version outputs the version identifier of the Isabelle
  5660 distribution being used.
  5661 
  5662 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  5663 (containing Boolean satisfiability problems) into Isabelle/HOL
  5664 theories.
  5665 
  5666 
  5667 
  5668 New in Isabelle2004 (April 2004)
  5669 --------------------------------
  5670 
  5671 *** General ***
  5672 
  5673 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  5674   Replaces linorder.ML.
  5675 
  5676 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  5677   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  5678   (\<a>...\<z>), are now considered normal letters, and can therefore
  5679   be used anywhere where an ASCII letter (a...zA...Z) has until
  5680   now. COMPATIBILITY: This obviously changes the parsing of some
  5681   terms, especially where a symbol has been used as a binder, say
  5682   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  5683   as an identifier.  Fix it by inserting a space around former
  5684   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  5685   existing theory and ML files.
  5686 
  5687 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  5688 
  5689 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  5690   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  5691   a normal (but invisible) letter. For multiple letter subscripts repeat
  5692   \<^isub> like this: x\<^isub>1\<^isub>2.
  5693 
  5694 * Pure: There are now sub-/superscripts that can span more than one
  5695   character. Text between \<^bsub> and \<^esub> is set in subscript in
  5696   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  5697   superscript. The new control characters are not identifier parts.
  5698 
  5699 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5700   content of "..." to the latex file instead of \isacntrl... . The "..."
  5701   may consist of any printable characters excluding the end bracket >.
  5702 
  5703 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5704   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5705   declare constants "final", which prevents their being given a definition
  5706   later.  It is useful for constants whose behaviour is fixed axiomatically
  5707   rather than definitionally, such as the meta-logic connectives.
  5708 
  5709 * Pure: 'instance' now handles general arities with general sorts
  5710   (i.e. intersections of classes),
  5711 
  5712 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5713   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5714   It can be changed to alter the colors/layout of generated pages.
  5715 
  5716 
  5717 *** Isar ***
  5718 
  5719 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5720   cut_tac, subgoal_tac and thin_tac:
  5721   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5722     locales are no longer forced to write Isar proof scripts.
  5723     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5724     emulations.
  5725   - INCOMPATIBILITY: names of variables to be instantiated may no
  5726     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5727     This is consistent with the instantiation attribute "where".
  5728 
  5729 * Attributes "where" and "of":
  5730   - Now take type variables of instantiated theorem into account when reading
  5731     the instantiation string.  This fixes a bug that caused instantiated
  5732     theorems to have too special types in some circumstances.
  5733   - "where" permits explicit instantiations of type variables.
  5734 
  5735 * Calculation commands "moreover" and "also" no longer interfere with
  5736   current facts ("this"), admitting arbitrary combinations with "then"
  5737   and derived forms.
  5738 
  5739 * Locales:
  5740   - Goal statements involving the context element "includes" no longer
  5741     generate theorems with internal delta predicates (those ending on
  5742     "_axioms") in the premise.
  5743     Resolve particular premise with <locale>.intro to obtain old form.
  5744   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5745     specification and "includes" elements in goal statement.
  5746   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5747     [intro?] and [elim?] (respectively) by default.
  5748   - Experimental command for instantiation of locales in proof contexts:
  5749         instantiate <label>[<attrs>]: <loc>
  5750     Instantiates locale <loc> and adds all its theorems to the current context
  5751     taking into account their attributes.  Label and attrs are optional
  5752     modifiers, like in theorem declarations.  If present, names of
  5753     instantiated theorems are qualified with <label>, and the attributes
  5754     <attrs> are applied after any attributes these theorems might have already.
  5755       If the locale has assumptions, a chained fact of the form
  5756     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5757     are derived.  The command does not support old-style locales declared
  5758     with "locale (open)".
  5759       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5760 
  5761 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5762   (Isar) contexts.
  5763 
  5764 
  5765 *** HOL ***
  5766 
  5767 * Proof import: new image HOL4 contains the imported library from
  5768   the HOL4 system with about 2500 theorems. It is imported by
  5769   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5770   can be used like any other Isabelle image.  See
  5771   HOL/Import/HOL/README for more information.
  5772 
  5773 * Simplifier:
  5774   - Much improved handling of linear and partial orders.
  5775     Reasoners for linear and partial orders are set up for type classes
  5776     "linorder" and "order" respectively, and are added to the default simpset
  5777     as solvers.  This means that the simplifier can build transitivity chains
  5778     to solve goals from the assumptions.
  5779   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5780     of blast or auto after simplification become unnecessary because the goal
  5781     is solved by simplification already.
  5782 
  5783 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5784     all proved in axiomatic type classes for semirings, rings and fields.
  5785 
  5786 * Numerics:
  5787   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5788     now formalized using the Ring_and_Field theory mentioned above.
  5789   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5790     than before, because now they are set up once in a generic manner.
  5791   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5792     Look for the general versions in Ring_and_Field (and Power if they concern
  5793     exponentiation).
  5794 
  5795 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5796 
  5797 * Records:
  5798   - Record types are now by default printed with their type abbreviation
  5799     instead of the list of all field types. This can be configured via
  5800     the reference "print_record_type_abbr".
  5801   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5802     (not enabled by default).
  5803   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5804     EX x. x = sel r to True (not enabled by default).
  5805   - Tactic "record_split_simp_tac" to split and simplify records added.
  5806 
  5807 * 'specification' command added, allowing for definition by
  5808   specification.  There is also an 'ax_specification' command that
  5809   introduces the new constants axiomatically.
  5810 
  5811 * arith(_tac) is now able to generate counterexamples for reals as well.
  5812 
  5813 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5814 
  5815 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5816   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5817 
  5818 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5819   matrix theory to linear programming.
  5820 
  5821 * Unions and Intersections:
  5822   The latex output syntax of UN and INT has been changed
  5823   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5824   i.e. the index formulae has become a subscript.
  5825   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5826 
  5827 * Unions and Intersections over Intervals:
  5828   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5829   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5830   like in normal math, and corresponding versions for < and for intersection.
  5831 
  5832 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5833   lexicographic dictonary ordering has been added as "lexord".
  5834 
  5835 * ML: the legacy theory structures Int and List have been removed. They had
  5836   conflicted with ML Basis Library structures having the same names.
  5837 
  5838 * 'refute' command added to search for (finite) countermodels.  Only works
  5839   for a fragment of HOL.  The installation of an external SAT solver is
  5840   highly recommended.  See "HOL/Refute.thy" for details.
  5841 
  5842 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5843   formulae under an assignment of free variables to random values.
  5844   In contrast to 'refute', it can deal with inductive datatypes,
  5845   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5846   for examples.
  5847 
  5848 
  5849 *** HOLCF ***
  5850 
  5851 * Streams now come with concatenation and are part of the HOLCF image
  5852 
  5853 
  5854 
  5855 New in Isabelle2003 (May 2003)
  5856 ------------------------------
  5857 
  5858 *** General ***
  5859 
  5860 * Provers/simplifier:
  5861 
  5862   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5863     Assumptions are now subject to complete mutual simplification,
  5864     not just from left to right. The simplifier now preserves
  5865     the order of assumptions.
  5866 
  5867     Potential INCOMPATIBILITY:
  5868 
  5869     -- simp sometimes diverges where the old version did
  5870        not, e.g. invoking simp on the goal
  5871 
  5872         [| P (f x); y = x; f x = f y |] ==> Q
  5873 
  5874        now gives rise to the infinite reduction sequence
  5875 
  5876         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5877 
  5878        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5879        kind of problem.
  5880 
  5881     -- Tactics combining classical reasoner and simplification (such as auto)
  5882        are also affected by this change, because many of them rely on
  5883        simp. They may sometimes diverge as well or yield a different numbers
  5884        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5885        in case of problems. Sometimes subsequent calls to the classical
  5886        reasoner will fail because a preceeding call to the simplifier too
  5887        eagerly simplified the goal, e.g. deleted redundant premises.
  5888 
  5889   - The simplifier trace now shows the names of the applied rewrite rules
  5890 
  5891   - You can limit the number of recursive invocations of the simplifier
  5892     during conditional rewriting (where the simplifie tries to solve the
  5893     conditions before applying the rewrite rule):
  5894     ML "simp_depth_limit := n"
  5895     where n is an integer. Thus you can force termination where previously
  5896     the simplifier would diverge.
  5897 
  5898   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5899 
  5900   - No longer aborts on failed congruence proof.  Instead, the
  5901     congruence is ignored.
  5902 
  5903 * Pure: New generic framework for extracting programs from constructive
  5904   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5905   as HOL/Extraction for some case studies.
  5906 
  5907 * Pure: The main goal of the proof state is no longer shown by default, only
  5908 the subgoals. This behaviour is controlled by a new flag.
  5909    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5910 (ML: Proof.show_main_goal).
  5911 
  5912 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5913 rules whose conclusion matches subgoal 1:
  5914       PG menu: Isabelle/Isar -> Show me -> matching rules
  5915 The rules are ordered by how closely they match the subgoal.
  5916 In particular, rules that solve a subgoal outright are displayed first
  5917 (or rather last, the way they are printed).
  5918 (ML: ProofGeneral.print_intros())
  5919 
  5920 * Pure: New flag trace_unify_fail causes unification to print
  5921 diagnostic information (PG: in trace buffer) when it fails. This is
  5922 useful for figuring out why single step proofs like rule, erule or
  5923 assumption failed.
  5924 
  5925 * Pure: Locale specifications now produce predicate definitions
  5926 according to the body of text (covering assumptions modulo local
  5927 definitions); predicate "loc_axioms" covers newly introduced text,
  5928 while "loc" is cumulative wrt. all included locale expressions; the
  5929 latter view is presented only on export into the global theory
  5930 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5931 on the old view without predicates;
  5932 
  5933 * Pure: predefined locales "var" and "struct" are useful for sharing
  5934 parameters (as in CASL, for example); just specify something like
  5935 ``var x + var y + struct M'' as import;
  5936 
  5937 * Pure: improved thms_containing: proper indexing of facts instead of
  5938 raw theorems; check validity of results wrt. current name space;
  5939 include local facts of proof configuration (also covers active
  5940 locales), cover fixed variables in index; may use "_" in term
  5941 specification; an optional limit for the number of printed facts may
  5942 be given (the default is 40);
  5943 
  5944 * Pure: disallow duplicate fact bindings within new-style theory files
  5945 (batch-mode only);
  5946 
  5947 * Provers: improved induct method: assumptions introduced by case
  5948 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5949 the goal statement); "foo" still refers to all facts collectively;
  5950 
  5951 * Provers: the function blast.overloaded has been removed: all constants
  5952 are regarded as potentially overloaded, which improves robustness in exchange
  5953 for slight decrease in efficiency;
  5954 
  5955 * Provers/linorder: New generic prover for transitivity reasoning over
  5956 linear orders.  Note: this prover is not efficient!
  5957 
  5958 * Isar: preview of problems to finish 'show' now produce an error
  5959 rather than just a warning (in interactive mode);
  5960 
  5961 
  5962 *** HOL ***
  5963 
  5964 * arith(_tac)
  5965 
  5966  - Produces a counter example if it cannot prove a goal.
  5967    Note that the counter example may be spurious if the goal is not a formula
  5968    of quantifier-free linear arithmetic.
  5969    In ProofGeneral the counter example appears in the trace buffer.
  5970 
  5971  - Knows about div k and mod k where k is a numeral of type nat or int.
  5972 
  5973  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  5974    linear arithmetic fails. This takes account of quantifiers and divisibility.
  5975    Presburger arithmetic can also be called explicitly via presburger(_tac).
  5976 
  5977 * simp's arithmetic capabilities have been enhanced a bit: it now
  5978 takes ~= in premises into account (by performing a case split);
  5979 
  5980 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  5981 are distributed over a sum of terms;
  5982 
  5983 * New tactic "trans_tac" and method "trans" instantiate
  5984 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  5985 "<=", "<" and "=").
  5986 
  5987 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  5988 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  5989 
  5990 * 'typedef' command has new option "open" to suppress the set
  5991 definition;
  5992 
  5993 * functions Min and Max on finite sets have been introduced (theory
  5994 Finite_Set);
  5995 
  5996 * attribute [symmetric] now works for relations as well; it turns
  5997 (x,y) : R^-1 into (y,x) : R, and vice versa;
  5998 
  5999 * induct over a !!-quantified statement (say !!x1..xn):
  6000   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  6001 
  6002 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  6003 %x. None. Warning: empty_def now refers to the previously hidden definition
  6004 of the empty set.
  6005 
  6006 * Algebra: formalization of classical algebra.  Intended as base for
  6007 any algebraic development in Isabelle.  Currently covers group theory
  6008 (up to Sylow's theorem) and ring theory (Universal Property of
  6009 Univariate Polynomials).  Contributions welcome;
  6010 
  6011 * GroupTheory: deleted, since its material has been moved to Algebra;
  6012 
  6013 * Complex: new directory of the complex numbers with numeric constants,
  6014 nonstandard complex numbers, and some complex analysis, standard and
  6015 nonstandard (Jacques Fleuriot);
  6016 
  6017 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  6018 
  6019 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  6020 Fleuriot);
  6021 
  6022 * Real/HahnBanach: updated and adapted to locales;
  6023 
  6024 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  6025 Gray and Kramer);
  6026 
  6027 * UNITY: added the Meier-Sanders theory of progress sets;
  6028 
  6029 * MicroJava: bytecode verifier and lightweight bytecode verifier
  6030 as abstract algorithms, instantiated to the JVM;
  6031 
  6032 * Bali: Java source language formalization. Type system, operational
  6033 semantics, axiomatic semantics. Supported language features:
  6034 classes, interfaces, objects,virtual methods, static methods,
  6035 static/instance fields, arrays, access modifiers, definite
  6036 assignment, exceptions.
  6037 
  6038 
  6039 *** ZF ***
  6040 
  6041 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  6042 universe, etc.);
  6043 
  6044 * Main ZF: virtually all theories converted to new-style format;
  6045 
  6046 
  6047 *** ML ***
  6048 
  6049 * Pure: Tactic.prove provides sane interface for internal proofs;
  6050 omits the infamous "standard" operation, so this is more appropriate
  6051 than prove_goalw_cterm in many situations (e.g. in simprocs);
  6052 
  6053 * Pure: improved error reporting of simprocs;
  6054 
  6055 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  6056 up simprocs;
  6057 
  6058 
  6059 *** Document preparation ***
  6060 
  6061 * uses \par instead of \\ for line breaks in theory text. This may
  6062 shift some page breaks in large documents. To get the old behaviour
  6063 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  6064 
  6065 * minimized dependencies of isabelle.sty and isabellesym.sty on
  6066 other packages
  6067 
  6068 * \<euro> now needs package babel/greek instead of marvosym (which
  6069 broke \Rightarrow)
  6070 
  6071 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  6072 textcomp package)
  6073 
  6074 
  6075 
  6076 New in Isabelle2002 (March 2002)
  6077 --------------------------------
  6078 
  6079 *** Document preparation ***
  6080 
  6081 * greatly simplified document preparation setup, including more
  6082 graceful interpretation of isatool usedir -i/-d/-D options, and more
  6083 instructive isatool mkdir; users should basically be able to get
  6084 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  6085 users may run a separate document processing stage manually like this:
  6086 "isatool usedir -D output HOL Test && isatool document Test/output";
  6087 
  6088 * theory dependency graph may now be incorporated into documents;
  6089 isatool usedir -g true will produce session_graph.eps/.pdf for use
  6090 with \includegraphics of LaTeX;
  6091 
  6092 * proper spacing of consecutive markup elements, especially text
  6093 blocks after section headings;
  6094 
  6095 * support bold style (for single symbols only), input syntax is like
  6096 this: "\<^bold>\<alpha>" or "\<^bold>A";
  6097 
  6098 * \<bullet> is now output as bold \cdot by default, which looks much
  6099 better in printed text;
  6100 
  6101 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  6102 note that these symbols are currently unavailable in Proof General /
  6103 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  6104 
  6105 * isatool latex no longer depends on changed TEXINPUTS, instead
  6106 isatool document copies the Isabelle style files to the target
  6107 location;
  6108 
  6109 
  6110 *** Isar ***
  6111 
  6112 * Pure/Provers: improved proof by cases and induction;
  6113   - 'case' command admits impromptu naming of parameters (such as
  6114     "case (Suc n)");
  6115   - 'induct' method divinates rule instantiation from the inductive
  6116     claim; no longer requires excessive ?P bindings for proper
  6117     instantiation of cases;
  6118   - 'induct' method properly enumerates all possibilities of set/type
  6119     rules; as a consequence facts may be also passed through *type*
  6120     rules without further ado;
  6121   - 'induct' method now derives symbolic cases from the *rulified*
  6122     rule (before it used to rulify cases stemming from the internal
  6123     atomized version); this means that the context of a non-atomic
  6124     statement becomes is included in the hypothesis, avoiding the
  6125     slightly cumbersome show "PROP ?case" form;
  6126   - 'induct' may now use elim-style induction rules without chaining
  6127     facts, using ``missing'' premises from the goal state; this allows
  6128     rules stemming from inductive sets to be applied in unstructured
  6129     scripts, while still benefitting from proper handling of non-atomic
  6130     statements; NB: major inductive premises need to be put first, all
  6131     the rest of the goal is passed through the induction;
  6132   - 'induct' proper support for mutual induction involving non-atomic
  6133     rule statements (uses the new concept of simultaneous goals, see
  6134     below);
  6135   - append all possible rule selections, but only use the first
  6136     success (no backtracking);
  6137   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  6138   - undeclared rule case names default to numbers 1, 2, 3, ...;
  6139   - added 'print_induct_rules' (covered by help item in recent Proof
  6140     General versions);
  6141   - moved induct/cases attributes to Pure, methods to Provers;
  6142   - generic method setup instantiated for FOL and HOL;
  6143 
  6144 * Pure: support multiple simultaneous goal statements, for example
  6145 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  6146 meta-level mechanism, this acts as if several individual goals had
  6147 been stated separately; in particular common proof methods need to be
  6148 repeated in order to cover all claims; note that a single elimination
  6149 step is *not* sufficient to establish the two conjunctions, so this
  6150 fails:
  6151 
  6152   assume "A & B" then have A and B ..   (*".." fails*)
  6153 
  6154 better use "obtain" in situations as above; alternative refer to
  6155 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  6156 
  6157 * Pure: proper integration with ``locales''; unlike the original
  6158 version by Florian Kammller, Isar locales package high-level proof
  6159 contexts rather than raw logical ones (e.g. we admit to include
  6160 attributes everywhere); operations on locales include merge and
  6161 rename; support for implicit arguments (``structures''); simultaneous
  6162 type-inference over imports and text; see also HOL/ex/Locales.thy for
  6163 some examples;
  6164 
  6165 * Pure: the following commands have been ``localized'', supporting a
  6166 target locale specification "(in name)": 'lemma', 'theorem',
  6167 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  6168 stored both within the locale and at the theory level (exported and
  6169 qualified by the locale name);
  6170 
  6171 * Pure: theory goals may now be specified in ``long'' form, with
  6172 ad-hoc contexts consisting of arbitrary locale elements. for example
  6173 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  6174 definitions may be given, too); the result is a meta-level rule with
  6175 the context elements being discharged in the obvious way;
  6176 
  6177 * Pure: new proof command 'using' allows to augment currently used
  6178 facts after a goal statement ('using' is syntactically analogous to
  6179 'apply', but acts on the goal's facts only); this allows chained facts
  6180 to be separated into parts given before and after a claim, as in
  6181 ``from a and b have C using d and e <proof>'';
  6182 
  6183 * Pure: renamed "antecedent" case to "rule_context";
  6184 
  6185 * Pure: new 'judgment' command records explicit information about the
  6186 object-logic embedding (used by several tools internally); no longer
  6187 use hard-wired "Trueprop";
  6188 
  6189 * Pure: added 'corollary' command;
  6190 
  6191 * Pure: fixed 'token_translation' command;
  6192 
  6193 * Pure: removed obsolete 'exported' attribute;
  6194 
  6195 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  6196 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  6197 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  6198 
  6199 * Pure: method 'atomize' presents local goal premises as object-level
  6200 statements (atomic meta-level propositions); setup controlled via
  6201 rewrite rules declarations of 'atomize' attribute; example
  6202 application: 'induct' method with proper rule statements in improper
  6203 proof *scripts*;
  6204 
  6205 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  6206 now consider the syntactic context of assumptions, giving a better
  6207 chance to get type-inference of the arguments right (this is
  6208 especially important for locales);
  6209 
  6210 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  6211 mode;
  6212 
  6213 * Pure/obtain: the formal conclusion "thesis", being marked as
  6214 ``internal'', may no longer be reference directly in the text;
  6215 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  6216 situations;
  6217 
  6218 * Pure: generic 'sym' attribute which declares a rule both as pure
  6219 'elim?' and for the 'symmetric' operation;
  6220 
  6221 * Pure: marginal comments ``--'' may now occur just anywhere in the
  6222 text; the fixed correlation with particular command syntax has been
  6223 discontinued;
  6224 
  6225 * Pure: new method 'rules' is particularly well-suited for proof
  6226 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  6227 but often produces more compact proof terms with less detours;
  6228 
  6229 * Pure/Provers/classical: simplified integration with pure rule
  6230 attributes and methods; the classical "intro?/elim?/dest?"
  6231 declarations coincide with the pure ones; the "rule" method no longer