NEWS
author haftmann
Wed Jul 20 22:14:39 2011 +0200 (2011-07-20)
changeset 43940 26ca0bad226a
parent 43899 60ef6abb2f92
child 43957 64f88ef1835e
child 43967 610efb6bda1f
permissions -rw-r--r--
class complete_linorder
     1 Isabelle NEWS -- history user-relevant changes
     2 ==============================================
     3 
     4 New in this Isabelle version
     5 ----------------------------
     6 
     7 *** General ***
     8 
     9 * Theory loader: source files are identified by content via SHA1
    10 digests.  Discontinued former path/modtime identification and optional
    11 ISABELLE_FILE_IDENT plugin scripts.
    12 
    13 * Parallelization of nested Isar proofs is subject to
    14 Goal.parallel_proofs_threshold (default 100).  See also isabelle
    15 usedir option -Q.
    16 
    17 * Discontinued support for Poly/ML 5.2, which was the last version
    18 without proper multithreading and TimeLimit implementation.
    19 
    20 * Discontinued old lib/scripts/polyml-platform, which has been
    21 obsolete since Isabelle2009-2.
    22 
    23 * Theory loader: source files are exclusively located via the master
    24 directory of each theory node (where the .thy file itself resides).
    25 The global load path (such as src/HOL/Library) has been discontinued.
    26 Note that the path element ~~ may be used to reference theories in the
    27 Isabelle home folder -- for instance, "~~/src/HOL/Library/FuncSet".
    28 INCOMPATIBILITY.
    29 
    30 * Various optional external tools are referenced more robustly and
    31 uniformly by explicit Isabelle settings as follows:
    32 
    33   ISABELLE_CSDP   (formerly CSDP_EXE)
    34   ISABELLE_GHC    (formerly EXEC_GHC or GHC_PATH)
    35   ISABELLE_OCAML  (formerly EXEC_OCAML)
    36   ISABELLE_SWIPL  (formerly EXEC_SWIPL)
    37   ISABELLE_YAP    (formerly EXEC_YAP)
    38 
    39 Note that automated detection from the file-system or search path has
    40 been discontinued.  INCOMPATIBILITY.
    41 
    42 * Name space: former unsynchronized references are now proper
    43 configuration options, with more conventional names:
    44 
    45   long_names   ~> names_long
    46   short_names  ~> names_short
    47   unique_names ~> names_unique
    48 
    49 Minor INCOMPATIBILITY, need to declare options in context like this:
    50 
    51   declare [[names_unique = false]]
    52 
    53 * Literal facts `prop` may contain dummy patterns, e.g. `_ = _`.  Note
    54 that the result needs to be unique, which means fact specifications
    55 may have to be refined after enriching a proof context.
    56 
    57 * Isabelle/Isar reference manual provides more formal references in
    58 syntax diagrams.
    59 
    60 
    61 *** HOL ***
    62 
    63 * Classes bot and top require underlying partial order rather than preorder:
    64 uniqueness of bot and top is guaranteed.  INCOMPATIBILITY.
    65 
    66 * Class complete_lattice: generalized a couple of lemmas from sets;
    67 generalized theorems INF_cong and SUP_cong.  New type classes for complete
    68 boolean algebras and complete linear orderes.  Lemmas Inf_less_iff,
    69 less_Sup_iff, INF_less_iff, less_SUP_iff now reside in class complete_linorder.
    70 More consistent and less misunderstandable names:
    71   INFI_def ~> INF_def
    72   SUPR_def ~> SUP_def
    73   le_SUPI ~> le_SUP_I
    74   le_SUPI2 ~> le_SUP_I2
    75   le_INFI ~> le_INF_I
    76   INFI_bool_eq ~> INF_bool_eq
    77   SUPR_bool_eq ~> SUP_bool_eq
    78   INFI_apply ~> INF_apply
    79   SUPR_apply ~> SUP_apply
    80 INCOMPATIBILITY.
    81 
    82 * Archimedian_Field.thy:
    83     floor now is defined as parameter of a separate type class floor_ceiling.
    84  
    85 * Finite_Set.thy: more coherent development of fold_set locales:
    86 
    87     locale fun_left_comm ~> locale comp_fun_commute
    88     locale fun_left_comm_idem ~> locale comp_fun_idem
    89     
    90 Both use point-free characterisation; interpretation proofs may need adjustment.
    91 INCOMPATIBILITY.
    92 
    93 * Code generation:
    94   - theory Library/Code_Char_ord provides native ordering of characters
    95     in the target language.
    96     
    97 * Declare ext [intro] by default.  Rare INCOMPATIBILITY.
    98 
    99 * Nitpick:
   100   - Added "need" and "total_consts" options.
   101   - Reintroduced "show_skolems" option by popular demand.
   102   - Renamed attribute: nitpick_def ~> nitpick_unfold.
   103     INCOMPATIBILITY.
   104 
   105 * Sledgehammer:
   106   - sledgehammer available_provers ~> sledgehammer supported_provers.
   107     INCOMPATIBILITY.
   108   - Added support for SNARK and ToFoF-E on SystemOnTPTP and for simply typed
   109     TPTP problems (TFF).
   110   - Added "preplay_timeout", "slicing", "type_enc", "sound", "max_mono_iters",
   111     and "max_new_mono_instances" options.
   112   - Removed "explicit_apply" and "full_types" options as well as "Full Types"
   113     Proof General menu item. INCOMPATIBILITY.
   114 
   115 * Metis:
   116   - Removed "metisF" -- use "metis" instead. INCOMPATIBILITY.
   117   - Obsoleted "metisFT" -- use "metis (full_types)" instead. INCOMPATIBILITY.
   118 
   119 * "try":
   120   - Renamed "try_methods" and added "simp:", "intro:", "dest:", and "elim:"
   121     options. INCOMPATIBILITY.
   122   - Introduced "try" that not only runs "try_methods" but also "solve_direct",
   123     "sledgehammer", "quickcheck", and "nitpick".
   124 
   125 * Quickcheck:
   126   - Added "eval" option to evaluate terms for the found counterexample
   127     (currently only supported by the default (exhaustive) tester)
   128   - Added post-processing of terms to obtain readable counterexamples
   129     (currently only supported by the default (exhaustive) tester)
   130   - New counterexample generator quickcheck[narrowing] enables
   131     narrowing-based testing.
   132     It requires that the Glasgow Haskell compiler is installed and
   133     its location is known to Isabelle with the environment variable
   134     ISABELLE_GHC.
   135 
   136 * Function package: discontinued option "tailrec".
   137 INCOMPATIBILITY. Use partial_function instead.
   138 
   139 * HOL-Probability:
   140   - Caratheodory's extension lemma is now proved for ring_of_sets.
   141   - Infinite products of probability measures are now available.
   142   - Use extended reals instead of positive extended reals.
   143     INCOMPATIBILITY.
   144 
   145 
   146 *** Document preparation ***
   147 
   148 * Discontinued special treatment of hard tabulators, which are better
   149 avoided in the first place.  Implicit tab-width is 1.
   150 
   151 * Antiquotation @{rail} layouts railroad syntax diagrams, see also
   152 isar-ref manual.
   153 
   154 * Antiquotation @{value} evaluates the given term and presents its result.
   155 
   156 * Localized \isabellestyle switch can be used within blocks or groups
   157 like this:
   158 
   159   \isabellestyle{it}  %preferred default
   160   {\isabellestylett @{text "typewriter stuff"}}
   161 
   162 * New term style "isub" as ad-hoc conversion of variables x1, y23 into
   163 subscripted form x\<^isub>1, y\<^isub>2\<^isub>3.
   164 
   165 * Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
   166 (e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).
   167 
   168 
   169 *** ML ***
   170 
   171 * The inner syntax of sort/type/term/prop supports inlined YXML
   172 representations within quoted string tokens.  By encoding logical
   173 entities via Term_XML (in ML or Scala) concrete syntax can be
   174 bypassed, which is particularly useful for producing bits of text
   175 under external program control.
   176 
   177 * Antiquotations for ML and document preparation are managed as theory
   178 data, which requires explicit setup.
   179 
   180 * Isabelle_Process.is_active allows tools to check if the official
   181 process wrapper is running (Isabelle/Scala/jEdit) or the old TTY loop
   182 (better known as Proof General).
   183 
   184 * Structure Proof_Context follows standard naming scheme.  Old
   185 ProofContext is still available for some time as legacy alias.
   186 
   187 * Structure Timing provides various operations for timing; supersedes
   188 former start_timing/end_timing etc.
   189 
   190 * Path.print is the official way to show file-system paths to users
   191 (including quotes etc.).
   192 
   193 * Inner syntax: identifiers in parse trees of generic categories
   194 "logic", "aprop", "idt" etc. carry position information (disguised as
   195 type constraints).  Occasional INCOMPATIBILITY with non-compliant
   196 translations that choke on unexpected type constraints.  Positions can
   197 be stripped in ML translations via Syntax.strip_positions /
   198 Syntax.strip_positions_ast, or via the syntax constant
   199 "_strip_positions" within parse trees.  As last resort, positions can
   200 be disabled via the configuration option Syntax.positions, which is
   201 called "syntax_positions" in Isar attribute syntax.
   202 
   203 * Discontinued special status of various ML structures that contribute
   204 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
   205 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
   206 refer directly to Ast.Constant, Lexicon.is_identifier,
   207 Syntax_Trans.mk_binder_tr etc.
   208 
   209 * Typed print translation: discontinued show_sorts argument, which is
   210 already available via context of "advanced" translation.
   211 
   212 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
   213 goal states; body tactic needs to address all subgoals uniformly.
   214 
   215 * Slightly more special eq_list/eq_set, with shortcut involving
   216 pointer equality (assumes that eq relation is reflexive).
   217 
   218 * Classical tactics use proper Proof.context instead of historic types
   219 claset/clasimpset.  Old-style declarations like addIs, addEs, addDs
   220 operate directly on Proof.context.  Raw type claset retains its use as
   221 snapshot of the classical context, which can be recovered via
   222 (put_claset HOL_cs) etc.  Type clasimpset has been discontinued.
   223 INCOMPATIBILITY, classical tactics and derived proof methods require
   224 proper Proof.context.
   225 
   226 * Scala layer provides JVM method invocation service for static
   227 methods of type (String)String, see Invoke_Scala.method in ML.
   228 For example:
   229 
   230   Invoke_Scala.method "java.lang.System.getProperty" "java.home"
   231 
   232 
   233 
   234 New in Isabelle2011 (January 2011)
   235 ----------------------------------
   236 
   237 *** General ***
   238 
   239 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
   240 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
   241 useful tooltips and hyperlinks produced from its static analysis.  The
   242 bundled component provides an executable Isabelle tool that can be run
   243 like this:
   244 
   245   Isabelle2011/bin/isabelle jedit
   246 
   247 * Significantly improved Isabelle/Isar implementation manual.
   248 
   249 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
   250 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
   251 while the default heap location within that directory lacks that extra
   252 suffix.  This isolates multiple Isabelle installations from each
   253 other, avoiding problems with old settings in new versions.
   254 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
   255 
   256 * Source files are always encoded as UTF-8, instead of old-fashioned
   257 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
   258 the following package declarations:
   259 
   260   \usepackage[utf8]{inputenc}
   261   \usepackage{textcomp}
   262 
   263 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
   264 a Unicode character is treated as a single symbol, not a sequence of
   265 non-ASCII bytes as before.  Since Isabelle/ML string literals may
   266 contain symbols without further backslash escapes, Unicode can now be
   267 used here as well.  Recall that Symbol.explode in ML provides a
   268 consistent view on symbols, while raw explode (or String.explode)
   269 merely give a byte-oriented representation.
   270 
   271 * Theory loader: source files are primarily located via the master
   272 directory of each theory node (where the .thy file itself resides).
   273 The global load path is still partially available as legacy feature.
   274 Minor INCOMPATIBILITY due to subtle change in file lookup: use
   275 explicit paths, relatively to the theory.
   276 
   277 * Special treatment of ML file names has been discontinued.
   278 Historically, optional extensions .ML or .sml were added on demand --
   279 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
   280 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
   281 
   282 * Various options that affect pretty printing etc. are now properly
   283 handled within the context via configuration options, instead of
   284 unsynchronized references or print modes.  There are both ML Config.T
   285 entities and Isar declaration attributes to access these.
   286 
   287   ML (Config.T)                 Isar (attribute)
   288 
   289   eta_contract                  eta_contract
   290   show_brackets                 show_brackets
   291   show_sorts                    show_sorts
   292   show_types                    show_types
   293   show_question_marks           show_question_marks
   294   show_consts                   show_consts
   295   show_abbrevs                  show_abbrevs
   296 
   297   Syntax.ast_trace              syntax_ast_trace
   298   Syntax.ast_stat               syntax_ast_stat
   299   Syntax.ambiguity_level        syntax_ambiguity_level
   300 
   301   Goal_Display.goals_limit      goals_limit
   302   Goal_Display.show_main_goal   show_main_goal
   303 
   304   Method.rule_trace             rule_trace
   305 
   306   Thy_Output.display            thy_output_display
   307   Thy_Output.quotes             thy_output_quotes
   308   Thy_Output.indent             thy_output_indent
   309   Thy_Output.source             thy_output_source
   310   Thy_Output.break              thy_output_break
   311 
   312 Note that corresponding "..._default" references in ML may only be
   313 changed globally at the ROOT session setup, but *not* within a theory.
   314 The option "show_abbrevs" supersedes the former print mode
   315 "no_abbrevs" with inverted meaning.
   316 
   317 * More systematic naming of some configuration options.
   318 INCOMPATIBILITY.
   319 
   320   trace_simp  ~>  simp_trace
   321   debug_simp  ~>  simp_debug
   322 
   323 * Support for real valued configuration options, using simplistic
   324 floating-point notation that coincides with the inner syntax for
   325 float_token.
   326 
   327 * Support for real valued preferences (with approximative PGIP type):
   328 front-ends need to accept "pgint" values in float notation.
   329 INCOMPATIBILITY.
   330 
   331 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
   332 DejaVu Sans.
   333 
   334 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   335 
   336 
   337 *** Pure ***
   338 
   339 * Command 'type_synonym' (with single argument) replaces somewhat
   340 outdated 'types', which is still available as legacy feature for some
   341 time.
   342 
   343 * Command 'nonterminal' (with 'and' separated list of arguments)
   344 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
   345 
   346 * Command 'notepad' replaces former 'example_proof' for
   347 experimentation in Isar without any result.  INCOMPATIBILITY.
   348 
   349 * Locale interpretation commands 'interpret' and 'sublocale' accept
   350 lists of equations to map definitions in a locale to appropriate
   351 entities in the context of the interpretation.  The 'interpretation'
   352 command already provided this functionality.
   353 
   354 * Diagnostic command 'print_dependencies' prints the locale instances
   355 that would be activated if the specified expression was interpreted in
   356 the current context.  Variant "print_dependencies!" assumes a context
   357 without interpretations.
   358 
   359 * Diagnostic command 'print_interps' prints interpretations in proofs
   360 in addition to interpretations in theories.
   361 
   362 * Discontinued obsolete 'global' and 'local' commands to manipulate
   363 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
   364 Sign.root_path and Sign.local_path may be applied directly where this
   365 feature is still required for historical reasons.
   366 
   367 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
   368 'definition' instead.
   369 
   370 * The "prems" fact, which refers to the accidental collection of
   371 foundational premises in the context, is now explicitly marked as
   372 legacy feature and will be discontinued soon.  Consider using "assms"
   373 of the head statement or reference facts by explicit names.
   374 
   375 * Document antiquotations @{class} and @{type} print classes and type
   376 constructors.
   377 
   378 * Document antiquotation @{file} checks file/directory entries within
   379 the local file system.
   380 
   381 
   382 *** HOL ***
   383 
   384 * Coercive subtyping: functions can be declared as coercions and type
   385 inference will add them as necessary upon input of a term.  Theory
   386 Complex_Main declares real :: nat => real and real :: int => real as
   387 coercions. A coercion function f is declared like this:
   388 
   389   declare [[coercion f]]
   390 
   391 To lift coercions through type constructors (e.g. from nat => real to
   392 nat list => real list), map functions can be declared, e.g.
   393 
   394   declare [[coercion_map map]]
   395 
   396 Currently coercion inference is activated only in theories including
   397 real numbers, i.e. descendants of Complex_Main.  This is controlled by
   398 the configuration option "coercion_enabled", e.g. it can be enabled in
   399 other theories like this:
   400 
   401   declare [[coercion_enabled]]
   402 
   403 * Command 'partial_function' provides basic support for recursive
   404 function definitions over complete partial orders.  Concrete instances
   405 are provided for i) the option type, ii) tail recursion on arbitrary
   406 types, and iii) the heap monad of Imperative_HOL.  See
   407 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
   408 for examples.
   409 
   410 * Function package: f.psimps rules are no longer implicitly declared
   411 as [simp].  INCOMPATIBILITY.
   412 
   413 * Datatype package: theorems generated for executable equality (class
   414 "eq") carry proper names and are treated as default code equations.
   415 
   416 * Inductive package: now offers command 'inductive_simps' to
   417 automatically derive instantiated and simplified equations for
   418 inductive predicates, similar to 'inductive_cases'.
   419 
   420 * Command 'enriched_type' allows to register properties of the
   421 functorial structure of types.
   422 
   423 * Improved infrastructure for term evaluation using code generator
   424 techniques, in particular static evaluation conversions.
   425 
   426 * Code generator: Scala (2.8 or higher) has been added to the target
   427 languages.
   428 
   429 * Code generator: globbing constant expressions "*" and "Theory.*"
   430 have been replaced by the more idiomatic "_" and "Theory._".
   431 INCOMPATIBILITY.
   432 
   433 * Code generator: export_code without explicit file declaration prints
   434 to standard output.  INCOMPATIBILITY.
   435 
   436 * Code generator: do not print function definitions for case
   437 combinators any longer.
   438 
   439 * Code generator: simplification with rules determined with
   440 src/Tools/Code/code_simp.ML and method "code_simp".
   441 
   442 * Code generator for records: more idiomatic representation of record
   443 types.  Warning: records are not covered by ancient SML code
   444 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
   445 rep_datatype declaration helps to succeed then:
   446 
   447   record 'a foo = ...
   448   ...
   449   rep_datatype foo_ext ...
   450 
   451 * Records: logical foundation type for records does not carry a
   452 '_type' suffix any longer (obsolete due to authentic syntax).
   453 INCOMPATIBILITY.
   454 
   455 * Quickcheck now by default uses exhaustive testing instead of random
   456 testing.  Random testing can be invoked by "quickcheck [random]",
   457 exhaustive testing by "quickcheck [exhaustive]".
   458 
   459 * Quickcheck instantiates polymorphic types with small finite
   460 datatypes by default. This enables a simple execution mechanism to
   461 handle quantifiers and function equality over the finite datatypes.
   462 
   463 * Quickcheck random generator has been renamed from "code" to
   464 "random".  INCOMPATIBILITY.
   465 
   466 * Quickcheck now has a configurable time limit which is set to 30
   467 seconds by default. This can be changed by adding [timeout = n] to the
   468 quickcheck command. The time limit for Auto Quickcheck is still set
   469 independently.
   470 
   471 * Quickcheck in locales considers interpretations of that locale for
   472 counter example search.
   473 
   474 * Sledgehammer:
   475   - Added "smt" and "remote_smt" provers based on the "smt" proof
   476     method. See the Sledgehammer manual for details ("isabelle doc
   477     sledgehammer").
   478   - Renamed commands:
   479     sledgehammer atp_info ~> sledgehammer running_provers
   480     sledgehammer atp_kill ~> sledgehammer kill_provers
   481     sledgehammer available_atps ~> sledgehammer available_provers
   482     INCOMPATIBILITY.
   483   - Renamed options:
   484     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
   485     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
   486     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
   487     (and "ms" and "min" are no longer supported)
   488     INCOMPATIBILITY.
   489 
   490 * Nitpick:
   491   - Renamed options:
   492     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
   493     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
   494     INCOMPATIBILITY.
   495   - Added support for partial quotient types.
   496   - Added local versions of the "Nitpick.register_xxx" functions.
   497   - Added "whack" option.
   498   - Allow registration of quotient types as codatatypes.
   499   - Improved "merge_type_vars" option to merge more types.
   500   - Removed unsound "fast_descrs" option.
   501   - Added custom symmetry breaking for datatypes, making it possible to reach
   502     higher cardinalities.
   503   - Prevent the expansion of too large definitions.
   504 
   505 * Proof methods "metis" and "meson" now have configuration options
   506 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
   507 to diagnose these tools. E.g.
   508 
   509     using [[metis_trace = true]]
   510 
   511 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
   512 manually as command 'solve_direct'.
   513 
   514 * The default SMT solver Z3 must be enabled explicitly (due to
   515 licensing issues) by setting the environment variable
   516 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
   517 commercial applications, the SMT solver CVC3 is provided as fall-back;
   518 changing the SMT solver is done via the configuration option
   519 "smt_solver".
   520 
   521 * Remote SMT solvers need to be referred to by the "remote_" prefix,
   522 i.e. "remote_cvc3" and "remote_z3".
   523 
   524 * Added basic SMT support for datatypes, records, and typedefs using
   525 the oracle mode (no proofs).  Direct support of pairs has been dropped
   526 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
   527 support for a similar behavior).  Minor INCOMPATIBILITY.
   528 
   529 * Changed SMT configuration options:
   530   - Renamed:
   531     z3_proofs ~> smt_oracle (with inverted meaning)
   532     z3_trace_assms ~> smt_trace_used_facts
   533     INCOMPATIBILITY.
   534   - Added:
   535     smt_verbose
   536     smt_random_seed
   537     smt_datatypes
   538     smt_infer_triggers
   539     smt_monomorph_limit
   540     cvc3_options
   541     remote_cvc3_options
   542     remote_z3_options
   543     yices_options
   544 
   545 * Boogie output files (.b2i files) need to be declared in the theory
   546 header.
   547 
   548 * Simplification procedure "list_to_set_comprehension" rewrites list
   549 comprehensions applied to List.set to set comprehensions.  Occasional
   550 INCOMPATIBILITY, may be deactivated like this:
   551 
   552   declare [[simproc del: list_to_set_comprehension]]
   553 
   554 * Removed old version of primrec package.  INCOMPATIBILITY.
   555 
   556 * Removed simplifier congruence rule of "prod_case", as has for long
   557 been the case with "split".  INCOMPATIBILITY.
   558 
   559 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
   560 
   561 * Removed [split_format ... and ... and ...] version of
   562 [split_format].  Potential INCOMPATIBILITY.
   563 
   564 * Predicate "sorted" now defined inductively, with nice induction
   565 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
   566 
   567 * Constant "contents" renamed to "the_elem", to free the generic name
   568 contents for other uses.  INCOMPATIBILITY.
   569 
   570 * Renamed class eq and constant eq (for code generation) to class
   571 equal and constant equal, plus renaming of related facts and various
   572 tuning.  INCOMPATIBILITY.
   573 
   574 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
   575 
   576 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
   577 INCOMPATIBILITY.
   578 
   579 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
   580 avoid confusion with finite sets.  INCOMPATIBILITY.
   581 
   582 * Abandoned locales equiv, congruent and congruent2 for equivalence
   583 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
   584 for congruent(2)).
   585 
   586 * Some previously unqualified names have been qualified:
   587 
   588   types
   589     bool ~> HOL.bool
   590     nat ~> Nat.nat
   591 
   592   constants
   593     Trueprop ~> HOL.Trueprop
   594     True ~> HOL.True
   595     False ~> HOL.False
   596     op & ~> HOL.conj
   597     op | ~> HOL.disj
   598     op --> ~> HOL.implies
   599     op = ~> HOL.eq
   600     Not ~> HOL.Not
   601     The ~> HOL.The
   602     All ~> HOL.All
   603     Ex ~> HOL.Ex
   604     Ex1 ~> HOL.Ex1
   605     Let ~> HOL.Let
   606     If ~> HOL.If
   607     Ball ~> Set.Ball
   608     Bex ~> Set.Bex
   609     Suc ~> Nat.Suc
   610     Pair ~> Product_Type.Pair
   611     fst ~> Product_Type.fst
   612     snd ~> Product_Type.snd
   613     curry ~> Product_Type.curry
   614     op : ~> Set.member
   615     Collect ~> Set.Collect
   616 
   617 INCOMPATIBILITY.
   618 
   619 * More canonical naming convention for some fundamental definitions:
   620 
   621     bot_bool_eq ~> bot_bool_def
   622     top_bool_eq ~> top_bool_def
   623     inf_bool_eq ~> inf_bool_def
   624     sup_bool_eq ~> sup_bool_def
   625     bot_fun_eq  ~> bot_fun_def
   626     top_fun_eq  ~> top_fun_def
   627     inf_fun_eq  ~> inf_fun_def
   628     sup_fun_eq  ~> sup_fun_def
   629 
   630 INCOMPATIBILITY.
   631 
   632 * More stylized fact names:
   633 
   634   expand_fun_eq ~> fun_eq_iff
   635   expand_set_eq ~> set_eq_iff
   636   set_ext       ~> set_eqI
   637   nat_number    ~> eval_nat_numeral
   638 
   639 INCOMPATIBILITY.
   640 
   641 * Refactoring of code-generation specific operations in theory List:
   642 
   643   constants
   644     null ~> List.null
   645 
   646   facts
   647     mem_iff ~> member_def
   648     null_empty ~> null_def
   649 
   650 INCOMPATIBILITY.  Note that these were not supposed to be used
   651 regularly unless for striking reasons; their main purpose was code
   652 generation.
   653 
   654 Various operations from the Haskell prelude are used for generating
   655 Haskell code.
   656 
   657 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
   658 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
   659 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
   660 
   661 * Abolished some non-alphabetic type names: "prod" and "sum" replace
   662 "*" and "+" respectively.  INCOMPATIBILITY.
   663 
   664 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
   665 "Sum_Type.Plus" instead.
   666 
   667 * Constant "split" has been merged with constant "prod_case"; names of
   668 ML functions, facts etc. involving split have been retained so far,
   669 though.  INCOMPATIBILITY.
   670 
   671 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
   672 instead.  INCOMPATIBILITY.
   673 
   674 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
   675 INCOMPATIBILITY.
   676 
   677 * Former theory Library/Enum is now part of the HOL-Main image.
   678 INCOMPATIBILITY: all constants of the Enum theory now have to be
   679 referred to by its qualified name.
   680 
   681   enum    ~>  Enum.enum
   682   nlists  ~>  Enum.nlists
   683   product ~>  Enum.product
   684 
   685 * Theory Library/Monad_Syntax provides do-syntax for monad types.
   686 Syntax in Library/State_Monad has been changed to avoid ambiguities.
   687 INCOMPATIBILITY.
   688 
   689 * Theory Library/SetsAndFunctions has been split into
   690 Library/Function_Algebras and Library/Set_Algebras; canonical names
   691 for instance definitions for functions; various improvements.
   692 INCOMPATIBILITY.
   693 
   694 * Theory Library/Multiset provides stable quicksort implementation of
   695 sort_key.
   696 
   697 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
   698 INCOMPATIBILITY.
   699 
   700 * Session Multivariate_Analysis: introduced a type class for euclidean
   701 space.  Most theorems are now stated in terms of euclidean spaces
   702 instead of finite cartesian products.
   703 
   704   types
   705     real ^ 'n ~>  'a::real_vector
   706               ~>  'a::euclidean_space
   707               ~>  'a::ordered_euclidean_space
   708         (depends on your needs)
   709 
   710   constants
   711      _ $ _        ~> _ $$ _
   712      \<chi> x. _  ~> \<chi>\<chi> x. _
   713      CARD('n)     ~> DIM('a)
   714 
   715 Also note that the indices are now natural numbers and not from some
   716 finite type. Finite cartesian products of euclidean spaces, products
   717 of euclidean spaces the real and complex numbers are instantiated to
   718 be euclidean_spaces.  INCOMPATIBILITY.
   719 
   720 * Session Probability: introduced pextreal as positive extended real
   721 numbers.  Use pextreal as value for measures.  Introduce the
   722 Radon-Nikodym derivative, product spaces and Fubini's theorem for
   723 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
   724 the integral in Multivariate Analysis.  INCOMPATIBILITY.
   725 
   726 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   727 INCOMPATIBILITY.
   728 
   729 * Session SPARK (with image HOL-SPARK) provides commands to load and
   730 prove verification conditions generated by the SPARK Ada program
   731 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
   732 
   733 
   734 *** HOL-Algebra ***
   735 
   736 * Theorems for additive ring operations (locale abelian_monoid and
   737 descendants) are generated by interpretation from their multiplicative
   738 counterparts.  Names (in particular theorem names) have the mandatory
   739 qualifier 'add'.  Previous theorem names are redeclared for
   740 compatibility.
   741 
   742 * Structure "int_ring" is now an abbreviation (previously a
   743 definition).  This fits more natural with advanced interpretations.
   744 
   745 
   746 *** HOLCF ***
   747 
   748 * The domain package now runs in definitional mode by default: The
   749 former command 'new_domain' is now called 'domain'.  To use the domain
   750 package in its original axiomatic mode, use 'domain (unsafe)'.
   751 INCOMPATIBILITY.
   752 
   753 * The new class "domain" is now the default sort.  Class "predomain"
   754 is an unpointed version of "domain". Theories can be updated by
   755 replacing sort annotations as shown below.  INCOMPATIBILITY.
   756 
   757   'a::type ~> 'a::countable
   758   'a::cpo  ~> 'a::predomain
   759   'a::pcpo ~> 'a::domain
   760 
   761 * The old type class "rep" has been superseded by class "domain".
   762 Accordingly, users of the definitional package must remove any
   763 "default_sort rep" declarations.  INCOMPATIBILITY.
   764 
   765 * The domain package (definitional mode) now supports unpointed
   766 predomain argument types, as long as they are marked 'lazy'. (Strict
   767 arguments must be in class "domain".) For example, the following
   768 domain definition now works:
   769 
   770   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
   771 
   772 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
   773 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
   774 'a option, and 'a list.  Additionally, it configures fixrec and the
   775 domain package to work with these types.  For example:
   776 
   777   fixrec isInl :: "('a + 'b) u -> tr"
   778     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
   779 
   780   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
   781 
   782 * The "(permissive)" option of fixrec has been replaced with a
   783 per-equation "(unchecked)" option. See
   784 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
   785 
   786 * The "bifinite" class no longer fixes a constant "approx"; the class
   787 now just asserts that such a function exists.  INCOMPATIBILITY.
   788 
   789 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
   790 defines an embedding of type 'a defl into udom by default; instances
   791 of "bifinite" and "domain" classes are available in
   792 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
   793 
   794 * The syntax "REP('a)" has been replaced with "DEFL('a)".
   795 
   796 * The predicate "directed" has been removed.  INCOMPATIBILITY.
   797 
   798 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
   799 
   800 * The function "cprod_map" has been renamed to "prod_map".
   801 INCOMPATIBILITY.
   802 
   803 * The monadic bind operator on each powerdomain has new binder syntax
   804 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
   805 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
   806 
   807 * The infix syntax for binary union on each powerdomain has changed
   808 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
   809 syntax.  INCOMPATIBILITY.
   810 
   811 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
   812 still supported as an input translation.
   813 
   814 * Renamed some theorems (the original names are also still available).
   815 
   816   expand_fun_below   ~> fun_below_iff
   817   below_fun_ext      ~> fun_belowI
   818   expand_cfun_eq     ~> cfun_eq_iff
   819   ext_cfun           ~> cfun_eqI
   820   expand_cfun_below  ~> cfun_below_iff
   821   below_cfun_ext     ~> cfun_belowI
   822   cont2cont_Rep_CFun ~> cont2cont_APP
   823 
   824 * The Abs and Rep functions for various types have changed names.
   825 Related theorem names have also changed to match. INCOMPATIBILITY.
   826 
   827   Rep_CFun  ~> Rep_cfun
   828   Abs_CFun  ~> Abs_cfun
   829   Rep_Sprod ~> Rep_sprod
   830   Abs_Sprod ~> Abs_sprod
   831   Rep_Ssum  ~> Rep_ssum
   832   Abs_Ssum  ~> Abs_ssum
   833 
   834 * Lemmas with names of the form *_defined_iff or *_strict_iff have
   835 been renamed to *_bottom_iff.  INCOMPATIBILITY.
   836 
   837 * Various changes to bisimulation/coinduction with domain package:
   838 
   839   - Definitions of "bisim" constants no longer mention definedness.
   840   - With mutual recursion, "bisim" predicate is now curried.
   841   - With mutual recursion, each type gets a separate coind theorem.
   842   - Variable names in bisim_def and coinduct rules have changed.
   843 
   844 INCOMPATIBILITY.
   845 
   846 * Case combinators generated by the domain package for type "foo" are
   847 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
   848 
   849 * Several theorems have been renamed to more accurately reflect the
   850 names of constants and types involved.  INCOMPATIBILITY.
   851 
   852   thelub_const    ~> lub_const
   853   lub_const       ~> is_lub_const
   854   thelubI         ~> lub_eqI
   855   is_lub_lub      ~> is_lubD2
   856   lubI            ~> is_lub_lub
   857   unique_lub      ~> is_lub_unique
   858   is_ub_lub       ~> is_lub_rangeD1
   859   lub_bin_chain   ~> is_lub_bin_chain
   860   lub_fun         ~> is_lub_fun
   861   thelub_fun      ~> lub_fun
   862   thelub_cfun     ~> lub_cfun
   863   thelub_Pair     ~> lub_Pair
   864   lub_cprod       ~> is_lub_prod
   865   thelub_cprod    ~> lub_prod
   866   minimal_cprod   ~> minimal_prod
   867   inst_cprod_pcpo ~> inst_prod_pcpo
   868   UU_I            ~> bottomI
   869   compact_UU      ~> compact_bottom
   870   deflation_UU    ~> deflation_bottom
   871   finite_deflation_UU ~> finite_deflation_bottom
   872 
   873 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
   874 
   875   sq_ord_less_eq_trans ~> below_eq_trans
   876   sq_ord_eq_less_trans ~> eq_below_trans
   877   refl_less            ~> below_refl
   878   trans_less           ~> below_trans
   879   antisym_less         ~> below_antisym
   880   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
   881   box_less             ~> box_below
   882   rev_trans_less       ~> rev_below_trans
   883   not_less2not_eq      ~> not_below2not_eq
   884   less_UU_iff          ~> below_UU_iff
   885   flat_less_iff        ~> flat_below_iff
   886   adm_less             ~> adm_below
   887   adm_not_less         ~> adm_not_below
   888   adm_compact_not_less ~> adm_compact_not_below
   889   less_fun_def         ~> below_fun_def
   890   expand_fun_less      ~> fun_below_iff
   891   less_fun_ext         ~> fun_belowI
   892   less_discr_def       ~> below_discr_def
   893   discr_less_eq        ~> discr_below_eq
   894   less_unit_def        ~> below_unit_def
   895   less_cprod_def       ~> below_prod_def
   896   prod_lessI           ~> prod_belowI
   897   Pair_less_iff        ~> Pair_below_iff
   898   fst_less_iff         ~> fst_below_iff
   899   snd_less_iff         ~> snd_below_iff
   900   expand_cfun_less     ~> cfun_below_iff
   901   less_cfun_ext        ~> cfun_belowI
   902   injection_less       ~> injection_below
   903   less_up_def          ~> below_up_def
   904   not_Iup_less         ~> not_Iup_below
   905   Iup_less             ~> Iup_below
   906   up_less              ~> up_below
   907   Def_inject_less_eq   ~> Def_below_Def
   908   Def_less_is_eq       ~> Def_below_iff
   909   spair_less_iff       ~> spair_below_iff
   910   less_sprod           ~> below_sprod
   911   spair_less           ~> spair_below
   912   sfst_less_iff        ~> sfst_below_iff
   913   ssnd_less_iff        ~> ssnd_below_iff
   914   fix_least_less       ~> fix_least_below
   915   dist_less_one        ~> dist_below_one
   916   less_ONE             ~> below_ONE
   917   ONE_less_iff         ~> ONE_below_iff
   918   less_sinlD           ~> below_sinlD
   919   less_sinrD           ~> below_sinrD
   920 
   921 
   922 *** FOL and ZF ***
   923 
   924 * All constant names are now qualified internally and use proper
   925 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
   926 
   927 
   928 *** ML ***
   929 
   930 * Antiquotation @{assert} inlines a function bool -> unit that raises
   931 Fail if the argument is false.  Due to inlining the source position of
   932 failed assertions is included in the error output.
   933 
   934 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
   935 text is in practice always evaluated with a stable theory checkpoint.
   936 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
   937 
   938 * Antiquotation @{theory A} refers to theory A from the ancestry of
   939 the current context, not any accidental theory loader state as before.
   940 Potential INCOMPATIBILITY, subtle change in semantics.
   941 
   942 * Syntax.pretty_priority (default 0) configures the required priority
   943 of pretty-printed output and thus affects insertion of parentheses.
   944 
   945 * Syntax.default_root (default "any") configures the inner syntax
   946 category (nonterminal symbol) for parsing of terms.
   947 
   948 * Former exception Library.UnequalLengths now coincides with
   949 ListPair.UnequalLengths.
   950 
   951 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
   952 main functionality is provided by structure Simplifier.
   953 
   954 * Renamed raw "explode" function to "raw_explode" to emphasize its
   955 meaning.  Note that internally to Isabelle, Symbol.explode is used in
   956 almost all situations.
   957 
   958 * Discontinued obsolete function sys_error and exception SYS_ERROR.
   959 See implementation manual for further details on exceptions in
   960 Isabelle/ML.
   961 
   962 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
   963 meaning.
   964 
   965 * Renamed structure PureThy to Pure_Thy and moved most of its
   966 operations to structure Global_Theory, to emphasize that this is
   967 rarely-used global-only stuff.
   968 
   969 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
   970 instead (or tracing for high-volume output).
   971 
   972 * Configuration option show_question_marks only affects regular pretty
   973 printing of types and terms, not raw Term.string_of_vname.
   974 
   975 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
   976 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
   977 @{thms} for most purposes.
   978 
   979 * ML structure Unsynchronized is never opened, not even in Isar
   980 interaction mode as before.  Old Unsynchronized.set etc. have been
   981 discontinued -- use plain := instead.  This should be *rare* anyway,
   982 since modern tools always work via official context data, notably
   983 configuration options.
   984 
   985 * Parallel and asynchronous execution requires special care concerning
   986 interrupts.  Structure Exn provides some convenience functions that
   987 avoid working directly with raw Interrupt.  User code must not absorb
   988 interrupts -- intermediate handling (for cleanup etc.) needs to be
   989 followed by re-raising of the original exception.  Another common
   990 source of mistakes are "handle _" patterns, which make the meaning of
   991 the program subject to physical effects of the environment.
   992 
   993 
   994 
   995 New in Isabelle2009-2 (June 2010)
   996 ---------------------------------
   997 
   998 *** General ***
   999 
  1000 * Authentic syntax for *all* logical entities (type classes, type
  1001 constructors, term constants): provides simple and robust
  1002 correspondence between formal entities and concrete syntax.  Within
  1003 the parse tree / AST representations, "constants" are decorated by
  1004 their category (class, type, const) and spelled out explicitly with
  1005 their full internal name.
  1006 
  1007 Substantial INCOMPATIBILITY concerning low-level syntax declarations
  1008 and translations (translation rules and translation functions in ML).
  1009 Some hints on upgrading:
  1010 
  1011   - Many existing uses of 'syntax' and 'translations' can be replaced
  1012     by more modern 'type_notation', 'notation' and 'abbreviation',
  1013     which are independent of this issue.
  1014 
  1015   - 'translations' require markup within the AST; the term syntax
  1016     provides the following special forms:
  1017 
  1018       CONST c   -- produces syntax version of constant c from context
  1019       XCONST c  -- literally c, checked as constant from context
  1020       c         -- literally c, if declared by 'syntax'
  1021 
  1022     Plain identifiers are treated as AST variables -- occasionally the
  1023     system indicates accidental variables via the error "rhs contains
  1024     extra variables".
  1025 
  1026     Type classes and type constructors are marked according to their
  1027     concrete syntax.  Some old translations rules need to be written
  1028     for the "type" category, using type constructor application
  1029     instead of pseudo-term application of the default category
  1030     "logic".
  1031 
  1032   - 'parse_translation' etc. in ML may use the following
  1033     antiquotations:
  1034 
  1035       @{class_syntax c}   -- type class c within parse tree / AST
  1036       @{term_syntax c}    -- type constructor c within parse tree / AST
  1037       @{const_syntax c}   -- ML version of "CONST c" above
  1038       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
  1039 
  1040   - Literal types within 'typed_print_translations', i.e. those *not*
  1041     represented as pseudo-terms are represented verbatim.  Use @{class
  1042     c} or @{type_name c} here instead of the above syntax
  1043     antiquotations.
  1044 
  1045 Note that old non-authentic syntax was based on unqualified base
  1046 names, so all of the above "constant" names would coincide.  Recall
  1047 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
  1048 diagnose syntax problems.
  1049 
  1050 * Type constructors admit general mixfix syntax, not just infix.
  1051 
  1052 * Concrete syntax may be attached to local entities without a proof
  1053 body, too.  This works via regular mixfix annotations for 'fix',
  1054 'def', 'obtain' etc. or via the explicit 'write' command, which is
  1055 similar to the 'notation' command in theory specifications.
  1056 
  1057 * Discontinued unnamed infix syntax (legacy feature for many years) --
  1058 need to specify constant name and syntax separately.  Internal ML
  1059 datatype constructors have been renamed from InfixName to Infix etc.
  1060 Minor INCOMPATIBILITY.
  1061 
  1062 * Schematic theorem statements need to be explicitly markup as such,
  1063 via commands 'schematic_lemma', 'schematic_theorem',
  1064 'schematic_corollary'.  Thus the relevance of the proof is made
  1065 syntactically clear, which impacts performance in a parallel or
  1066 asynchronous interactive environment.  Minor INCOMPATIBILITY.
  1067 
  1068 * Use of cumulative prems via "!" in some proof methods has been
  1069 discontinued (old legacy feature).
  1070 
  1071 * References 'trace_simp' and 'debug_simp' have been replaced by
  1072 configuration options stored in the context. Enabling tracing (the
  1073 case of debugging is similar) in proofs works via
  1074 
  1075   using [[trace_simp = true]]
  1076 
  1077 Tracing is then active for all invocations of the simplifier in
  1078 subsequent goal refinement steps. Tracing may also still be enabled or
  1079 disabled via the ProofGeneral settings menu.
  1080 
  1081 * Separate commands 'hide_class', 'hide_type', 'hide_const',
  1082 'hide_fact' replace the former 'hide' KIND command.  Minor
  1083 INCOMPATIBILITY.
  1084 
  1085 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
  1086 more efficient than combinations with -q1 or -q2.
  1087 
  1088 
  1089 *** Pure ***
  1090 
  1091 * Proofterms record type-class reasoning explicitly, using the
  1092 "unconstrain" operation internally.  This eliminates all sort
  1093 constraints from a theorem and proof, introducing explicit
  1094 OFCLASS-premises.  On the proof term level, this operation is
  1095 automatically applied at theorem boundaries, such that closed proofs
  1096 are always free of sort constraints.  INCOMPATIBILITY for tools that
  1097 inspect proof terms.
  1098 
  1099 * Local theory specifications may depend on extra type variables that
  1100 are not present in the result type -- arguments TYPE('a) :: 'a itself
  1101 are added internally.  For example:
  1102 
  1103   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
  1104 
  1105 * Predicates of locales introduced by classes carry a mandatory
  1106 "class" prefix.  INCOMPATIBILITY.
  1107 
  1108 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
  1109 
  1110 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
  1111 'class' instead.
  1112 
  1113 * Command 'code_reflect' allows to incorporate generated ML code into
  1114 runtime environment; replaces immature code_datatype antiquotation.
  1115 INCOMPATIBILITY.
  1116 
  1117 * Code generator: simple concept for abstract datatypes obeying
  1118 invariants.
  1119 
  1120 * Code generator: details of internal data cache have no impact on the
  1121 user space functionality any longer.
  1122 
  1123 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  1124 subgoals.  This is more appropriate for interpretations with 'where'.
  1125 INCOMPATIBILITY.
  1126 
  1127 * Command 'example_proof' opens an empty proof body.  This allows to
  1128 experiment with Isar, without producing any persistent result.
  1129 
  1130 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  1131 within a local theory context, with explicit checking of the
  1132 constructors involved (in contrast to the raw 'syntax' versions).
  1133 
  1134 * Commands 'types' and 'typedecl' now work within a local theory
  1135 context -- without introducing dependencies on parameters or
  1136 assumptions, which is not possible in Isabelle/Pure.
  1137 
  1138 * Command 'defaultsort' has been renamed to 'default_sort', it works
  1139 within a local theory context.  Minor INCOMPATIBILITY.
  1140 
  1141 
  1142 *** HOL ***
  1143 
  1144 * Command 'typedef' now works within a local theory context -- without
  1145 introducing dependencies on parameters or assumptions, which is not
  1146 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  1147 contain multiple interpretations of local typedefs (with different
  1148 non-emptiness proofs), even in a global theory context.
  1149 
  1150 * New package for quotient types.  Commands 'quotient_type' and
  1151 'quotient_definition' may be used for defining types and constants by
  1152 quotient constructions.  An example is the type of integers created by
  1153 quotienting pairs of natural numbers:
  1154 
  1155   fun
  1156     intrel :: "(nat * nat) => (nat * nat) => bool"
  1157   where
  1158     "intrel (x, y) (u, v) = (x + v = u + y)"
  1159 
  1160   quotient_type int = "nat * nat" / intrel
  1161     by (auto simp add: equivp_def expand_fun_eq)
  1162 
  1163   quotient_definition
  1164     "0::int" is "(0::nat, 0::nat)"
  1165 
  1166 The method "lifting" can be used to lift of theorems from the
  1167 underlying "raw" type to the quotient type.  The example
  1168 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  1169 construction and provides a reasoning infrastructure for finite sets.
  1170 
  1171 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  1172 clash with new theory Quotient in Main HOL.
  1173 
  1174 * Moved the SMT binding into the main HOL session, eliminating
  1175 separate HOL-SMT session.
  1176 
  1177 * List membership infix mem operation is only an input abbreviation.
  1178 INCOMPATIBILITY.
  1179 
  1180 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  1181 for future developements; former Library/Word.thy is still present in
  1182 the AFP entry RSAPPS.
  1183 
  1184 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  1185 longer shadowed.  INCOMPATIBILITY.
  1186 
  1187 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  1188 INCOMPATIBILITY.
  1189 
  1190 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  1191 INCOMPATIBILITY.
  1192 
  1193 * Dropped normalizing_semiring etc; use the facts in semiring classes
  1194 instead.  INCOMPATIBILITY.
  1195 
  1196 * Dropped several real-specific versions of lemmas about floor and
  1197 ceiling; use the generic lemmas from theory "Archimedean_Field"
  1198 instead.  INCOMPATIBILITY.
  1199 
  1200   floor_number_of_eq         ~> floor_number_of
  1201   le_floor_eq_number_of      ~> number_of_le_floor
  1202   le_floor_eq_zero           ~> zero_le_floor
  1203   le_floor_eq_one            ~> one_le_floor
  1204   floor_less_eq_number_of    ~> floor_less_number_of
  1205   floor_less_eq_zero         ~> floor_less_zero
  1206   floor_less_eq_one          ~> floor_less_one
  1207   less_floor_eq_number_of    ~> number_of_less_floor
  1208   less_floor_eq_zero         ~> zero_less_floor
  1209   less_floor_eq_one          ~> one_less_floor
  1210   floor_le_eq_number_of      ~> floor_le_number_of
  1211   floor_le_eq_zero           ~> floor_le_zero
  1212   floor_le_eq_one            ~> floor_le_one
  1213   floor_subtract_number_of   ~> floor_diff_number_of
  1214   floor_subtract_one         ~> floor_diff_one
  1215   ceiling_number_of_eq       ~> ceiling_number_of
  1216   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  1217   ceiling_le_zero_eq         ~> ceiling_le_zero
  1218   ceiling_le_eq_one          ~> ceiling_le_one
  1219   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  1220   less_ceiling_eq_zero       ~> zero_less_ceiling
  1221   less_ceiling_eq_one        ~> one_less_ceiling
  1222   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  1223   ceiling_less_eq_zero       ~> ceiling_less_zero
  1224   ceiling_less_eq_one        ~> ceiling_less_one
  1225   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  1226   le_ceiling_eq_zero         ~> zero_le_ceiling
  1227   le_ceiling_eq_one          ~> one_le_ceiling
  1228   ceiling_subtract_number_of ~> ceiling_diff_number_of
  1229   ceiling_subtract_one       ~> ceiling_diff_one
  1230 
  1231 * Theory "Finite_Set": various folding_XXX locales facilitate the
  1232 application of the various fold combinators on finite sets.
  1233 
  1234 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  1235 provides abstract red-black tree type which is backed by "RBT_Impl" as
  1236 implementation.  INCOMPATIBILTY.
  1237 
  1238 * Theory Library/Coinductive_List has been removed -- superseded by
  1239 AFP/thys/Coinductive.
  1240 
  1241 * Theory PReal, including the type "preal" and related operations, has
  1242 been removed.  INCOMPATIBILITY.
  1243 
  1244 * Real: new development using Cauchy Sequences.
  1245 
  1246 * Split off theory "Big_Operators" containing setsum, setprod,
  1247 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  1248 
  1249 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  1250 "Int" etc.  INCOMPATIBILITY.
  1251 
  1252 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  1253 
  1254 * New set of rules "ac_simps" provides combined assoc / commute
  1255 rewrites for all interpretations of the appropriate generic locales.
  1256 
  1257 * Renamed theory "OrderedGroup" to "Groups" and split theory
  1258 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  1259 appropriate and more consistent names suitable for name prefixes
  1260 within the HOL theories.  INCOMPATIBILITY.
  1261 
  1262 * Some generic constants have been put to appropriate theories:
  1263   - less_eq, less: Orderings
  1264   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  1265   - inverse, divide: Rings
  1266 INCOMPATIBILITY.
  1267 
  1268 * More consistent naming of type classes involving orderings (and
  1269 lattices):
  1270 
  1271     lower_semilattice                   ~> semilattice_inf
  1272     upper_semilattice                   ~> semilattice_sup
  1273 
  1274     dense_linear_order                  ~> dense_linorder
  1275 
  1276     pordered_ab_group_add               ~> ordered_ab_group_add
  1277     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  1278     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  1279     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  1280     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  1281     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  1282     pordered_cancel_semiring            ~> ordered_cancel_semiring
  1283     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  1284     pordered_comm_ring                  ~> ordered_comm_ring
  1285     pordered_comm_semiring              ~> ordered_comm_semiring
  1286     pordered_ring                       ~> ordered_ring
  1287     pordered_ring_abs                   ~> ordered_ring_abs
  1288     pordered_semiring                   ~> ordered_semiring
  1289 
  1290     ordered_ab_group_add                ~> linordered_ab_group_add
  1291     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  1292     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  1293     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  1294     ordered_field                       ~> linordered_field
  1295     ordered_field_no_lb                 ~> linordered_field_no_lb
  1296     ordered_field_no_ub                 ~> linordered_field_no_ub
  1297     ordered_field_dense_linear_order    ~> dense_linordered_field
  1298     ordered_idom                        ~> linordered_idom
  1299     ordered_ring                        ~> linordered_ring
  1300     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  1301     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  1302     ordered_ring_strict                 ~> linordered_ring_strict
  1303     ordered_semidom                     ~> linordered_semidom
  1304     ordered_semiring                    ~> linordered_semiring
  1305     ordered_semiring_1                  ~> linordered_semiring_1
  1306     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  1307     ordered_semiring_strict             ~> linordered_semiring_strict
  1308 
  1309   The following slightly odd type classes have been moved to a
  1310   separate theory Library/Lattice_Algebras:
  1311 
  1312     lordered_ab_group_add               ~> lattice_ab_group_add
  1313     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  1314     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  1315     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  1316     lordered_ring                       ~> lattice_ring
  1317 
  1318 INCOMPATIBILITY.
  1319 
  1320 * Refined field classes:
  1321   - classes division_ring_inverse_zero, field_inverse_zero,
  1322     linordered_field_inverse_zero include rule inverse 0 = 0 --
  1323     subsumes former division_by_zero class;
  1324   - numerous lemmas have been ported from field to division_ring.
  1325 INCOMPATIBILITY.
  1326 
  1327 * Refined algebra theorem collections:
  1328   - dropped theorem group group_simps, use algebra_simps instead;
  1329   - dropped theorem group ring_simps, use field_simps instead;
  1330   - proper theorem collection field_simps subsumes former theorem
  1331     groups field_eq_simps and field_simps;
  1332   - dropped lemma eq_minus_self_iff which is a duplicate for
  1333     equal_neg_zero.
  1334 INCOMPATIBILITY.
  1335 
  1336 * Theory Finite_Set and List: some lemmas have been generalized from
  1337 sets to lattices:
  1338 
  1339   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  1340   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  1341   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  1342   union_Union_fold_union        ~> sup_Sup_fold_sup
  1343   Inter_fold_inter              ~> Inf_fold_inf
  1344   Union_fold_union              ~> Sup_fold_sup
  1345   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  1346   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  1347   INTER_fold_inter              ~> INFI_fold_inf
  1348   UNION_fold_union              ~> SUPR_fold_sup
  1349 
  1350 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  1351 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  1352 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  1353 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  1354 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  1355 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  1356 
  1357 * Reorganized theory Multiset: swapped notation of pointwise and
  1358 multiset order:
  1359 
  1360   - pointwise ordering is instance of class order with standard syntax
  1361     <= and <;
  1362   - multiset ordering has syntax <=# and <#; partial order properties
  1363     are provided by means of interpretation with prefix
  1364     multiset_order;
  1365   - less duplication, less historical organization of sections,
  1366     conversion from associations lists to multisets, rudimentary code
  1367     generation;
  1368   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  1369     if needed.
  1370 
  1371 Renamed:
  1372 
  1373   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  1374   multi_count_ext  ~>  multiset_ext
  1375   diff_union_inverse2  ~>  diff_union_cancelR
  1376 
  1377 INCOMPATIBILITY.
  1378 
  1379 * Theory Permutation: replaced local "remove" by List.remove1.
  1380 
  1381 * Code generation: ML and OCaml code is decorated with signatures.
  1382 
  1383 * Theory List: added transpose.
  1384 
  1385 * Library/Nat_Bijection.thy is a collection of bijective functions
  1386 between nat and other types, which supersedes the older libraries
  1387 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  1388 
  1389   Constants:
  1390   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  1391   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  1392   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  1393   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  1394   Countable.pair_encode           ~> prod_encode
  1395   NatIso.prod2nat                 ~> prod_encode
  1396   NatIso.nat2prod                 ~> prod_decode
  1397   NatIso.sum2nat                  ~> sum_encode
  1398   NatIso.nat2sum                  ~> sum_decode
  1399   NatIso.list2nat                 ~> list_encode
  1400   NatIso.nat2list                 ~> list_decode
  1401   NatIso.set2nat                  ~> set_encode
  1402   NatIso.nat2set                  ~> set_decode
  1403 
  1404   Lemmas:
  1405   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  1406   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  1407   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  1408   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  1409   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  1410   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  1411   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  1412   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  1413   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  1414   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  1415   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  1416   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  1417   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  1418 
  1419 * Sledgehammer:
  1420   - Renamed ATP commands:
  1421     atp_info     ~> sledgehammer running_atps
  1422     atp_kill     ~> sledgehammer kill_atps
  1423     atp_messages ~> sledgehammer messages
  1424     atp_minimize ~> sledgehammer minimize
  1425     print_atps   ~> sledgehammer available_atps
  1426     INCOMPATIBILITY.
  1427   - Added user's manual ("isabelle doc sledgehammer").
  1428   - Added option syntax and "sledgehammer_params" to customize
  1429     Sledgehammer's behavior.  See the manual for details.
  1430   - Modified the Isar proof reconstruction code so that it produces
  1431     direct proofs rather than proofs by contradiction.  (This feature
  1432     is still experimental.)
  1433   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  1434     full-typed mode.
  1435   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  1436 
  1437 * Nitpick:
  1438   - Added and implemented "binary_ints" and "bits" options.
  1439   - Added "std" option and implemented support for nonstandard models.
  1440   - Added and implemented "finitize" option to improve the precision
  1441     of infinite datatypes based on a monotonicity analysis.
  1442   - Added support for quotient types.
  1443   - Added support for "specification" and "ax_specification"
  1444     constructs.
  1445   - Added support for local definitions (for "function" and
  1446     "termination" proofs).
  1447   - Added support for term postprocessors.
  1448   - Optimized "Multiset.multiset" and "FinFun.finfun".
  1449   - Improved efficiency of "destroy_constrs" optimization.
  1450   - Fixed soundness bugs related to "destroy_constrs" optimization and
  1451     record getters.
  1452   - Fixed soundness bug related to higher-order constructors.
  1453   - Fixed soundness bug when "full_descrs" is enabled.
  1454   - Improved precision of set constructs.
  1455   - Added "atoms" option.
  1456   - Added cache to speed up repeated Kodkod invocations on the same
  1457     problems.
  1458   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  1459     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  1460     "SAT4J_Light".  INCOMPATIBILITY.
  1461   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  1462     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  1463   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  1464 
  1465 * Method "induct" now takes instantiations of the form t, where t is not
  1466   a variable, as a shorthand for "x == t", where x is a fresh variable.
  1467   If this is not intended, t has to be enclosed in parentheses.
  1468   By default, the equalities generated by definitional instantiations
  1469   are pre-simplified, which may cause parameters of inductive cases
  1470   to disappear, or may even delete some of the inductive cases.
  1471   Use "induct (no_simp)" instead of "induct" to restore the old
  1472   behaviour. The (no_simp) option is also understood by the "cases"
  1473   and "nominal_induct" methods, which now perform pre-simplification, too.
  1474   INCOMPATIBILITY.
  1475 
  1476 
  1477 *** HOLCF ***
  1478 
  1479 * Variable names in lemmas generated by the domain package have
  1480 changed; the naming scheme is now consistent with the HOL datatype
  1481 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  1482 
  1483 * The domain package no longer defines the function "foo_copy" for
  1484 recursive domain "foo".  The reach lemma is now stated directly in
  1485 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  1486 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  1487 
  1488 * Most definedness lemmas generated by the domain package (previously
  1489 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  1490 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  1491 Proofs that used definedness lemmas as intro rules may break,
  1492 potential INCOMPATIBILITY.
  1493 
  1494 * Induction and casedist rules generated by the domain package now
  1495 declare proper case_names (one called "bottom", and one named for each
  1496 constructor).  INCOMPATIBILITY.
  1497 
  1498 * For mutually-recursive domains, separate "reach" and "take_lemma"
  1499 rules are generated for each domain, INCOMPATIBILITY.
  1500 
  1501   foo_bar.reach       ~> foo.reach  bar.reach
  1502   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  1503 
  1504 * Some lemmas generated by the domain package have been renamed for
  1505 consistency with the datatype package, INCOMPATIBILITY.
  1506 
  1507   foo.ind        ~> foo.induct
  1508   foo.finite_ind ~> foo.finite_induct
  1509   foo.coind      ~> foo.coinduct
  1510   foo.casedist   ~> foo.exhaust
  1511   foo.exhaust    ~> foo.nchotomy
  1512 
  1513 * For consistency with other definition packages, the fixrec package
  1514 now generates qualified theorem names, INCOMPATIBILITY.
  1515 
  1516   foo_simps  ~> foo.simps
  1517   foo_unfold ~> foo.unfold
  1518   foo_induct ~> foo.induct
  1519 
  1520 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  1521 method and internal fixrec proofs now use the default simpset instead.
  1522 INCOMPATIBILITY.
  1523 
  1524 * The "contlub" predicate has been removed.  Proof scripts should use
  1525 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  1526 
  1527 * The "admw" predicate has been removed, INCOMPATIBILITY.
  1528 
  1529 * The constants cpair, cfst, and csnd have been removed in favor of
  1530 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  1531 
  1532 
  1533 *** ML ***
  1534 
  1535 * Antiquotations for basic formal entities:
  1536 
  1537     @{class NAME}         -- type class
  1538     @{class_syntax NAME}  -- syntax representation of the above
  1539 
  1540     @{type_name NAME}     -- logical type
  1541     @{type_abbrev NAME}   -- type abbreviation
  1542     @{nonterminal NAME}   -- type of concrete syntactic category
  1543     @{type_syntax NAME}   -- syntax representation of any of the above
  1544 
  1545     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  1546     @{const_abbrev NAME}  -- abbreviated constant
  1547     @{const_syntax NAME}  -- syntax representation of any of the above
  1548 
  1549 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  1550 syntax constant (cf. 'syntax' command).
  1551 
  1552 * Antiquotation @{make_string} inlines a function to print arbitrary
  1553 values similar to the ML toplevel.  The result is compiler dependent
  1554 and may fall back on "?" in certain situations.
  1555 
  1556 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  1557 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  1558 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  1559 not work with the asynchronous Isar document model.
  1560 
  1561 * Configuration options now admit dynamic default values, depending on
  1562 the context or even global references.
  1563 
  1564 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  1565 uses an efficient external library if available (for Poly/ML).
  1566 
  1567 * Renamed some important ML structures, while keeping the old names
  1568 for some time as aliases within the structure Legacy:
  1569 
  1570   OuterKeyword  ~>  Keyword
  1571   OuterLex      ~>  Token
  1572   OuterParse    ~>  Parse
  1573   OuterSyntax   ~>  Outer_Syntax
  1574   PrintMode     ~>  Print_Mode
  1575   SpecParse     ~>  Parse_Spec
  1576   ThyInfo       ~>  Thy_Info
  1577   ThyLoad       ~>  Thy_Load
  1578   ThyOutput     ~>  Thy_Output
  1579   TypeInfer     ~>  Type_Infer
  1580 
  1581 Note that "open Legacy" simplifies porting of sources, but forgetting
  1582 to remove it again will complicate porting again in the future.
  1583 
  1584 * Most operations that refer to a global context are named
  1585 accordingly, e.g. Simplifier.global_context or
  1586 ProofContext.init_global.  There are some situations where a global
  1587 context actually works, but under normal circumstances one needs to
  1588 pass the proper local context through the code!
  1589 
  1590 * Discontinued old TheoryDataFun with its copy/init operation -- data
  1591 needs to be pure.  Functor Theory_Data_PP retains the traditional
  1592 Pretty.pp argument to merge, which is absent in the standard
  1593 Theory_Data version.
  1594 
  1595 * Sorts.certify_sort and derived "cert" operations for types and terms
  1596 no longer minimize sorts.  Thus certification at the boundary of the
  1597 inference kernel becomes invariant under addition of class relations,
  1598 which is an important monotonicity principle.  Sorts are now minimized
  1599 in the syntax layer only, at the boundary between the end-user and the
  1600 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  1601 explicitly in rare situations.
  1602 
  1603 * Renamed old-style Drule.standard to Drule.export_without_context, to
  1604 emphasize that this is in no way a standard operation.
  1605 INCOMPATIBILITY.
  1606 
  1607 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  1608 usual for resolution.  Rare INCOMPATIBILITY.
  1609 
  1610 * Renamed varify/unvarify operations to varify_global/unvarify_global
  1611 to emphasize that these only work in a global situation (which is
  1612 quite rare).
  1613 
  1614 * Curried take and drop in library.ML; negative length is interpreted
  1615 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  1616 
  1617 * Proof terms: type substitutions on proof constants now use canonical
  1618 order of type variables.  INCOMPATIBILITY for tools working with proof
  1619 terms.
  1620 
  1621 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  1622 may no longer carry premises.  User-level specifications are
  1623 transformed accordingly by Thm.add_axiom/add_def.
  1624 
  1625 
  1626 *** System ***
  1627 
  1628 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  1629 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  1630 proof terms are enabled unconditionally in the new HOL-Proofs image.
  1631 
  1632 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  1633 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  1634 respectively.
  1635 
  1636 * Old lib/scripts/polyml-platform is superseded by the
  1637 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  1638 variant, even on a 64 bit machine.  The following example setting
  1639 prefers 64 bit if available:
  1640 
  1641   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  1642 
  1643 * The preliminary Isabelle/jEdit application demonstrates the emerging
  1644 Isabelle/Scala layer for advanced prover interaction and integration.
  1645 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  1646 component.
  1647 
  1648 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  1649 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  1650 similar to the default assignment of the document preparation system
  1651 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  1652 provides some operations for direct access to the font without asking
  1653 the user for manual installation.
  1654 
  1655 
  1656 
  1657 New in Isabelle2009-1 (December 2009)
  1658 -------------------------------------
  1659 
  1660 *** General ***
  1661 
  1662 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  1663 one backslash should be used, even in ML sources.
  1664 
  1665 
  1666 *** Pure ***
  1667 
  1668 * Locale interpretation propagates mixins along the locale hierarchy.
  1669 The currently only available mixins are the equations used to map
  1670 local definitions to terms of the target domain of an interpretation.
  1671 
  1672 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  1673 loc" to print all interpretations of locale "loc" in the theory.
  1674 Interpretations in proofs are not shown.
  1675 
  1676 * Thoroughly revised locales tutorial.  New section on conditional
  1677 interpretation.
  1678 
  1679 * On instantiation of classes, remaining undefined class parameters
  1680 are formally declared.  INCOMPATIBILITY.
  1681 
  1682 
  1683 *** Document preparation ***
  1684 
  1685 * New generalized style concept for printing terms: @{foo (style) ...}
  1686 instead of @{foo_style style ...}  (old form is still retained for
  1687 backward compatibility).  Styles can be also applied for
  1688 antiquotations prop, term_type and typeof.
  1689 
  1690 
  1691 *** HOL ***
  1692 
  1693 * New proof method "smt" for a combination of first-order logic with
  1694 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  1695 fixed-size bitvectors; there is also basic support for higher-order
  1696 features (esp. lambda abstractions).  It is an incomplete decision
  1697 procedure based on external SMT solvers using the oracle mechanism;
  1698 for the SMT solver Z3, this method is proof-producing.  Certificates
  1699 are provided to avoid calling the external solvers solely for
  1700 re-checking proofs.  Due to a remote SMT service there is no need for
  1701 installing SMT solvers locally.  See src/HOL/SMT.
  1702 
  1703 * New commands to load and prove verification conditions generated by
  1704 the Boogie program verifier or derived systems (e.g. the Verifying C
  1705 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1706 
  1707 * New counterexample generator tool 'nitpick' based on the Kodkod
  1708 relational model finder.  See src/HOL/Tools/Nitpick and
  1709 src/HOL/Nitpick_Examples.
  1710 
  1711 * New commands 'code_pred' and 'values' to invoke the predicate
  1712 compiler and to enumerate values of inductive predicates.
  1713 
  1714 * A tabled implementation of the reflexive transitive closure.
  1715 
  1716 * New implementation of quickcheck uses generic code generator;
  1717 default generators are provided for all suitable HOL types, records
  1718 and datatypes.  Old quickcheck can be re-activated importing theory
  1719 Library/SML_Quickcheck.
  1720 
  1721 * New testing tool Mirabelle for automated proof tools.  Applies
  1722 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1723 every proof step in a theory.  To be used in batch mode via the
  1724 "mirabelle" utility.
  1725 
  1726 * New proof method "sos" (sum of squares) for nonlinear real
  1727 arithmetic (originally due to John Harison). It requires theory
  1728 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1729 works well in practice on quantifier-free real arithmetic with +, -,
  1730 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1731 inequalities between polynomials.  It makes use of external
  1732 semidefinite programming solvers.  Method "sos" generates a
  1733 certificate that can be pasted into the proof thus avoiding the need
  1734 to call an external tool every time the proof is checked.  See
  1735 src/HOL/Library/Sum_Of_Squares.
  1736 
  1737 * New method "linarith" invokes existing linear arithmetic decision
  1738 procedure only.
  1739 
  1740 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1741 
  1742 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1743 Causes full type information to be output to the ATPs.  This slows
  1744 ATPs down considerably but eliminates a source of unsound "proofs"
  1745 that fail later.
  1746 
  1747 * New method "metisFT": A version of metis that uses full type
  1748 information in order to avoid failures of proof reconstruction.
  1749 
  1750 * New evaluator "approximate" approximates an real valued term using
  1751 the same method as the approximation method.
  1752 
  1753 * Method "approximate" now supports arithmetic expressions as
  1754 boundaries of intervals and implements interval splitting and Taylor
  1755 series expansion.
  1756 
  1757 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1758 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1759 
  1760 * New theory SupInf of the supremum and infimum operators for sets of
  1761 reals.
  1762 
  1763 * New theory Probability, which contains a development of measure
  1764 theory, eventually leading to Lebesgue integration and probability.
  1765 
  1766 * Extended Multivariate Analysis to include derivation and Brouwer's
  1767 fixpoint theorem.
  1768 
  1769 * Reorganization of number theory, INCOMPATIBILITY:
  1770   - new number theory development for nat and int, in theories Divides
  1771     and GCD as well as in new session Number_Theory
  1772   - some constants and facts now suffixed with _nat and _int
  1773     accordingly
  1774   - former session NumberTheory now named Old_Number_Theory, including
  1775     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1776   - moved theory Pocklington from src/HOL/Library to
  1777     src/HOL/Old_Number_Theory
  1778 
  1779 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1780 lcm of finite and infinite sets. It is shown that they form a complete
  1781 lattice.
  1782 
  1783 * Class semiring_div requires superclass no_zero_divisors and proof of
  1784 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1785 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1786 generalized to class semiring_div, subsuming former theorems
  1787 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1788 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1789 INCOMPATIBILITY.
  1790 
  1791 * Refinements to lattice classes and sets:
  1792   - less default intro/elim rules in locale variant, more default
  1793     intro/elim rules in class variant: more uniformity
  1794   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1795     le_inf_iff
  1796   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1797     sup_aci)
  1798   - renamed ACI to inf_sup_aci
  1799   - new class "boolean_algebra"
  1800   - class "complete_lattice" moved to separate theory
  1801     "Complete_Lattice"; corresponding constants (and abbreviations)
  1802     renamed and with authentic syntax:
  1803     Set.Inf ~>    Complete_Lattice.Inf
  1804     Set.Sup ~>    Complete_Lattice.Sup
  1805     Set.INFI ~>   Complete_Lattice.INFI
  1806     Set.SUPR ~>   Complete_Lattice.SUPR
  1807     Set.Inter ~>  Complete_Lattice.Inter
  1808     Set.Union ~>  Complete_Lattice.Union
  1809     Set.INTER ~>  Complete_Lattice.INTER
  1810     Set.UNION ~>  Complete_Lattice.UNION
  1811   - authentic syntax for
  1812     Set.Pow
  1813     Set.image
  1814   - mere abbreviations:
  1815     Set.empty               (for bot)
  1816     Set.UNIV                (for top)
  1817     Set.inter               (for inf, formerly Set.Int)
  1818     Set.union               (for sup, formerly Set.Un)
  1819     Complete_Lattice.Inter  (for Inf)
  1820     Complete_Lattice.Union  (for Sup)
  1821     Complete_Lattice.INTER  (for INFI)
  1822     Complete_Lattice.UNION  (for SUPR)
  1823   - object-logic definitions as far as appropriate
  1824 
  1825 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1826 Un_subset_iff are explicitly deleted as default simp rules; then also
  1827 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1828 deleted to achieve the desired effect.
  1829 
  1830 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1831 rules by default any longer; the same applies to min_max.inf_absorb1
  1832 etc.  INCOMPATIBILITY.
  1833 
  1834 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1835 pred_set_conv by default.  INCOMPATIBILITY.
  1836 
  1837 * Power operations on relations and functions are now one dedicated
  1838 constant "compow" with infix syntax "^^".  Power operation on
  1839 multiplicative monoids retains syntax "^" and is now defined generic
  1840 in class power.  INCOMPATIBILITY.
  1841 
  1842 * Relation composition "R O S" now has a more standard argument order:
  1843 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1844 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1845 break, since the O_assoc rule was not rewritten like this.  Fix using
  1846 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1847 
  1848 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1849 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1850 INCOMPATIBILITY.
  1851 
  1852 * Most rules produced by inductive and datatype package have mandatory
  1853 prefixes.  INCOMPATIBILITY.
  1854 
  1855 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1856 the attribute of the same name.  Each of the theorems in the list
  1857 DERIV_intros assumes composition with an additional function and
  1858 matches a variable to the derivative, which has to be solved by the
  1859 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1860 of most elementary terms.  Former Maclauren.DERIV_tac and
  1861 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1862 INCOMPATIBILITY.
  1863 
  1864 * Code generator attributes follow the usual underscore convention:
  1865     code_unfold     replaces    code unfold
  1866     code_post       replaces    code post
  1867     etc.
  1868   INCOMPATIBILITY.
  1869 
  1870 * Renamed methods:
  1871     sizechange -> size_change
  1872     induct_scheme -> induction_schema
  1873   INCOMPATIBILITY.
  1874 
  1875 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1876 INCOMPATIBILITY, use "undefined" directly.
  1877 
  1878 * Renamed theorems:
  1879     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1880     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1881     Suc_plus1 -> Suc_eq_plus1
  1882     *anti_sym -> *antisym*
  1883     vector_less_eq_def -> vector_le_def
  1884   INCOMPATIBILITY.
  1885 
  1886 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1887 INCOMPATIBILITY.
  1888 
  1889 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1890 INCOMPATIBILITY.
  1891 
  1892 
  1893 *** HOLCF ***
  1894 
  1895 * Theory Representable defines a class "rep" of domains that are
  1896 representable (via an ep-pair) in the universal domain type "udom".
  1897 Instances are provided for all type constructors defined in HOLCF.
  1898 
  1899 * The 'new_domain' command is a purely definitional version of the
  1900 domain package, for representable domains.  Syntax is identical to the
  1901 old domain package.  The 'new_domain' package also supports indirect
  1902 recursion using previously-defined type constructors.  See
  1903 src/HOLCF/ex/New_Domain.thy for examples.
  1904 
  1905 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1906 on the left-hand side of an equation, and then performs
  1907 simplification.  Rewriting is done using rules declared with the
  1908 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1909 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1910 
  1911 * The pattern-match compiler in 'fixrec' can now handle constructors
  1912 with HOL function types.  Pattern-match combinators for the Pair
  1913 constructor are pre-configured.
  1914 
  1915 * The 'fixrec' package now produces better fixed-point induction rules
  1916 for mutually-recursive definitions:  Induction rules have conclusions
  1917 of the form "P foo bar" instead of "P <foo, bar>".
  1918 
  1919 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1920 been renamed to "below".  The name "below" now replaces "less" in many
  1921 theorem names.  (Legacy theorem names using "less" are still supported
  1922 as well.)
  1923 
  1924 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1925 patterns can be used to generate strictness rules, or to make
  1926 functions more strict (much like the bang-patterns supported by the
  1927 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1928 examples.
  1929 
  1930 
  1931 *** ML ***
  1932 
  1933 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1934 errors and run-time exceptions, including detailed source positions.
  1935 
  1936 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1937 identified entries, with some additional information such as source
  1938 position, logical grouping etc.
  1939 
  1940 * Theory and context data is now introduced by the simplified and
  1941 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1942 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1943 copy operation) is still available for some time.
  1944 
  1945 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1946 provides a high-level programming interface to synchronized state
  1947 variables with atomic update.  This works via pure function
  1948 application within a critical section -- its runtime should be as
  1949 short as possible; beware of deadlocks if critical code is nested,
  1950 either directly or indirectly via other synchronized variables!
  1951 
  1952 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1953 wraps raw ML references, explicitly indicating their non-thread-safe
  1954 behaviour.  The Isar toplevel keeps this structure open, to
  1955 accommodate Proof General as well as quick and dirty interactive
  1956 experiments with references.
  1957 
  1958 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1959 parallel tactical reasoning.
  1960 
  1961 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1962 are similar to SUBPROOF, but are slightly more flexible: only the
  1963 specified parts of the subgoal are imported into the context, and the
  1964 body tactic may introduce new subgoals and schematic variables.
  1965 
  1966 * Old tactical METAHYPS, which does not observe the proof context, has
  1967 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1968 or Subgoal.FOCUS etc.
  1969 
  1970 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  1971 functors have their own ML name space there is no point to mark them
  1972 separately.)  Minor INCOMPATIBILITY.
  1973 
  1974 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  1975 
  1976 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  1977 INCOMPATIBILITY.
  1978 
  1979 * Operations of structure Skip_Proof no longer require quick_and_dirty
  1980 mode, which avoids critical setmp.
  1981 
  1982 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  1983 combinators for "args".  INCOMPATIBILITY, need to use simplified
  1984 Attrib/Method.setup introduced in Isabelle2009.
  1985 
  1986 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  1987 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  1988 last resort.  INCOMPATIBILITY.
  1989 
  1990 * Display.pretty_thm now requires a proper context (cf. former
  1991 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  1992 or even Display.pretty_thm_without_context as last resort.
  1993 INCOMPATIBILITY.
  1994 
  1995 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  1996 Syntax.pretty_typ/term directly, preferably with proper context
  1997 instead of global theory.
  1998 
  1999 
  2000 *** System ***
  2001 
  2002 * Further fine tuning of parallel proof checking, scales up to 8 cores
  2003 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  2004 usedir option -q.
  2005 
  2006 * Support for additional "Isabelle components" via etc/components, see
  2007 also the system manual.
  2008 
  2009 * The isabelle makeall tool now operates on all components with
  2010 IsaMakefile, not just hardwired "logics".
  2011 
  2012 * Removed "compress" option from isabelle-process and isabelle usedir;
  2013 this is always enabled.
  2014 
  2015 * Discontinued support for Poly/ML 4.x versions.
  2016 
  2017 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  2018 on a given logic image.  This requires the lighttpd webserver and is
  2019 currently supported on Linux only.
  2020 
  2021 
  2022 
  2023 New in Isabelle2009 (April 2009)
  2024 --------------------------------
  2025 
  2026 *** General ***
  2027 
  2028 * Simplified main Isabelle executables, with less surprises on
  2029 case-insensitive file-systems (such as Mac OS).
  2030 
  2031   - The main Isabelle tool wrapper is now called "isabelle" instead of
  2032     "isatool."
  2033 
  2034   - The former "isabelle" alias for "isabelle-process" has been
  2035     removed (should rarely occur to regular users).
  2036 
  2037   - The former "isabelle-interface" and its alias "Isabelle" have been
  2038     removed (interfaces are now regular Isabelle tools).
  2039 
  2040 Within scripts and make files, the Isabelle environment variables
  2041 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  2042 respectively.  (The latter are still available as legacy feature.)
  2043 
  2044 The old isabelle-interface wrapper could react in confusing ways if
  2045 the interface was uninstalled or changed otherwise.  Individual
  2046 interface tool configuration is now more explicit, see also the
  2047 Isabelle system manual.  In particular, Proof General is now available
  2048 via "isabelle emacs".
  2049 
  2050 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  2051 purge installed copies of Isabelle executables and re-run "isabelle
  2052 install -p ...", or use symlinks.
  2053 
  2054 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  2055 old ~/isabelle, which was slightly non-standard and apt to cause
  2056 surprises on case-insensitive file-systems (such as Mac OS).
  2057 
  2058 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  2059 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  2060 care is required when using older releases of Isabelle.  Note that
  2061 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  2062 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  2063 
  2064 * Proofs of fully specified statements are run in parallel on
  2065 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  2066 a regular 4-core machine, if the initial heap space is made reasonably
  2067 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  2068 
  2069 * The main reference manuals ("isar-ref", "implementation", and
  2070 "system") have been updated and extended.  Formally checked references
  2071 as hyperlinks are now available uniformly.
  2072 
  2073 
  2074 *** Pure ***
  2075 
  2076 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  2077 respects.  The most important changes are listed below.  See the
  2078 Tutorial on Locales ("locales" manual) for details.
  2079 
  2080 - In locale expressions, instantiation replaces renaming.  Parameters
  2081 must be declared in a for clause.  To aid compatibility with previous
  2082 parameter inheritance, in locale declarations, parameters that are not
  2083 'touched' (instantiation position "_" or omitted) are implicitly added
  2084 with their syntax at the beginning of the for clause.
  2085 
  2086 - Syntax from abbreviations and definitions in locales is available in
  2087 locale expressions and context elements.  The latter is particularly
  2088 useful in locale declarations.
  2089 
  2090 - More flexible mechanisms to qualify names generated by locale
  2091 expressions.  Qualifiers (prefixes) may be specified in locale
  2092 expressions, and can be marked as mandatory (syntax: "name!:") or
  2093 optional (syntax "name?:").  The default depends for plain "name:"
  2094 depends on the situation where a locale expression is used: in
  2095 commands 'locale' and 'sublocale' prefixes are optional, in
  2096 'interpretation' and 'interpret' prefixes are mandatory.  The old
  2097 implicit qualifiers derived from the parameter names of a locale are
  2098 no longer generated.
  2099 
  2100 - Command "sublocale l < e" replaces "interpretation l < e".  The
  2101 instantiation clause in "interpretation" and "interpret" (square
  2102 brackets) is no longer available.  Use locale expressions.
  2103 
  2104 - When converting proof scripts, mandatory qualifiers in
  2105 'interpretation' and 'interpret' should be retained by default, even
  2106 if this is an INCOMPATIBILITY compared to former behavior.  In the
  2107 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  2108 in locale expressions range over a single locale instance only.
  2109 
  2110 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  2111 In existing theorem specifications replace the includes element by the
  2112 respective context elements of the included locale, omitting those
  2113 that are already present in the theorem specification.  Multiple
  2114 assume elements of a locale should be replaced by a single one
  2115 involving the locale predicate.  In the proof body, declarations (most
  2116 notably theorems) may be regained by interpreting the respective
  2117 locales in the proof context as required (command "interpret").
  2118 
  2119 If using "includes" in replacement of a target solely because the
  2120 parameter types in the theorem are not as general as in the target,
  2121 consider declaring a new locale with additional type constraints on
  2122 the parameters (context element "constrains").
  2123 
  2124 - Discontinued "locale (open)".  INCOMPATIBILITY.
  2125 
  2126 - Locale interpretation commands no longer attempt to simplify goal.
  2127 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  2128 methods intro_locales and unfold_locales to clarify.
  2129 
  2130 - Locale interpretation commands no longer accept interpretation
  2131 attributes.  INCOMPATIBILITY.
  2132 
  2133 * Class declaration: so-called "base sort" must not be given in import
  2134 list any longer, but is inferred from the specification.  Particularly
  2135 in HOL, write
  2136 
  2137     class foo = ...
  2138 
  2139 instead of
  2140 
  2141     class foo = type + ...
  2142 
  2143 * Class target: global versions of theorems stemming do not carry a
  2144 parameter prefix any longer.  INCOMPATIBILITY.
  2145 
  2146 * Class 'instance' command no longer accepts attached definitions.
  2147 INCOMPATIBILITY, use proper 'instantiation' target instead.
  2148 
  2149 * Recovered hiding of consts, which was accidentally broken in
  2150 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  2151 makes c inaccessible; consider using ``hide (open) const c'' instead.
  2152 
  2153 * Slightly more coherent Pure syntax, with updated documentation in
  2154 isar-ref manual.  Removed locales meta_term_syntax and
  2155 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  2156 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  2157 directly in regular applications.
  2158 
  2159 * There is a new syntactic category "float_const" for signed decimal
  2160 fractions (e.g. 123.45 or -123.45).
  2161 
  2162 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  2163 interface with 'setup' command instead.
  2164 
  2165 * Command 'local_setup' is similar to 'setup', but operates on a local
  2166 theory context.
  2167 
  2168 * The 'axiomatization' command now only works within a global theory
  2169 context.  INCOMPATIBILITY.
  2170 
  2171 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  2172 hypotheses.  Sorts required in the course of reasoning need to be
  2173 covered by the constraints in the initial statement, completed by the
  2174 type instance information of the background theory.  Non-trivial sort
  2175 hypotheses, which rarely occur in practice, may be specified via
  2176 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  2177 
  2178   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  2179 
  2180 The result contains an implicit sort hypotheses as before --
  2181 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  2182 normalization.
  2183 
  2184 * Generalized Isar history, with support for linear undo, direct state
  2185 addressing etc.
  2186 
  2187 * Changed defaults for unify configuration options:
  2188 
  2189   unify_trace_bound = 50 (formerly 25)
  2190   unify_search_bound = 60 (formerly 30)
  2191 
  2192 * Different bookkeeping for code equations (INCOMPATIBILITY):
  2193 
  2194   a) On theory merge, the last set of code equations for a particular
  2195      constant is taken (in accordance with the policy applied by other
  2196      parts of the code generator framework).
  2197 
  2198   b) Code equations stemming from explicit declarations (e.g. code
  2199      attribute) gain priority over default code equations stemming
  2200      from definition, primrec, fun etc.
  2201 
  2202 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  2203 
  2204 * Unified theorem tables for both code generators.  Thus [code
  2205 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  2206 
  2207 * Command 'find_consts' searches for constants based on type and name
  2208 patterns, e.g.
  2209 
  2210     find_consts "_ => bool"
  2211 
  2212 By default, matching is against subtypes, but it may be restricted to
  2213 the whole type.  Searching by name is possible.  Multiple queries are
  2214 conjunctive and queries may be negated by prefixing them with a
  2215 hyphen:
  2216 
  2217     find_consts strict: "_ => bool" name: "Int" -"int => int"
  2218 
  2219 * New 'find_theorems' criterion "solves" matches theorems that
  2220 directly solve the current goal (modulo higher-order unification).
  2221 
  2222 * Auto solve feature for main theorem statements: whenever a new goal
  2223 is stated, "find_theorems solves" is called; any theorems that could
  2224 solve the lemma directly are listed as part of the goal state.
  2225 Cf. associated options in Proof General Isabelle settings menu,
  2226 enabled by default, with reasonable timeout for pathological cases of
  2227 higher-order unification.
  2228 
  2229 
  2230 *** Document preparation ***
  2231 
  2232 * Antiquotation @{lemma} now imitates a regular terminal proof,
  2233 demanding keyword 'by' and supporting the full method expression
  2234 syntax just like the Isar command 'by'.
  2235 
  2236 
  2237 *** HOL ***
  2238 
  2239 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  2240 points Main and Complex_Main remain as before.
  2241 
  2242 * Logic image HOL-Plain provides a minimal HOL with the most important
  2243 tools available (inductive, datatype, primrec, ...).  This facilitates
  2244 experimentation and tool development.  Note that user applications
  2245 (and library theories) should never refer to anything below theory
  2246 Main, as before.
  2247 
  2248 * Logic image HOL-Main stops at theory Main, and thus facilitates
  2249 experimentation due to shorter build times.
  2250 
  2251 * Logic image HOL-NSA contains theories of nonstandard analysis which
  2252 were previously part of former HOL-Complex.  Entry point Hyperreal
  2253 remains valid, but theories formerly using Complex_Main should now use
  2254 new entry point Hypercomplex.
  2255 
  2256 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  2257 Posix processes.  Avoids potentially expensive forking of the ML
  2258 process.  New thread-based implementation also works on non-Unix
  2259 platforms (Cygwin).  Provers are no longer hardwired, but defined
  2260 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  2261 commands are covered in the isar-ref manual.
  2262 
  2263 * Wrapper scripts for remote SystemOnTPTP service allows to use
  2264 sledgehammer without local ATP installation (Vampire etc.). Other
  2265 provers may be included via suitable ML wrappers, see also
  2266 src/HOL/ATP_Linkup.thy.
  2267 
  2268 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  2269 menu.
  2270 
  2271 * The metis method no longer fails because the theorem is too trivial
  2272 (contains the empty clause).
  2273 
  2274 * The metis method now fails in the usual manner, rather than raising
  2275 an exception, if it determines that it cannot prove the theorem.
  2276 
  2277 * Method "coherent" implements a prover for coherent logic (see also
  2278 src/Tools/coherent.ML).
  2279 
  2280 * Constants "undefined" and "default" replace "arbitrary".  Usually
  2281 "undefined" is the right choice to replace "arbitrary", though
  2282 logically there is no difference.  INCOMPATIBILITY.
  2283 
  2284 * Command "value" now integrates different evaluation mechanisms.  The
  2285 result of the first successful evaluation mechanism is printed.  In
  2286 square brackets a particular named evaluation mechanisms may be
  2287 specified (currently, [SML], [code] or [nbe]).  See further
  2288 src/HOL/ex/Eval_Examples.thy.
  2289 
  2290 * Normalization by evaluation now allows non-leftlinear equations.
  2291 Declare with attribute [code nbe].
  2292 
  2293 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  2294 as the structured Isar versions "cases" and "induct", cf. the
  2295 corresponding "cases" and "induct" attributes.  Mutual induction rules
  2296 are now presented as a list of individual projections
  2297 (e.g. foo_bar.inducts for types foo and bar); the old format with
  2298 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  2299 rare situations a different rule is selected --- notably nested tuple
  2300 elimination instead of former prod.exhaust: use explicit (case_tac t
  2301 rule: prod.exhaust) here.
  2302 
  2303 * Attributes "cases", "induct", "coinduct" support "del" option.
  2304 
  2305 * Removed fact "case_split_thm", which duplicates "case_split".
  2306 
  2307 * The option datatype has been moved to a new theory Option.  Renamed
  2308 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  2309 
  2310 * New predicate "strict_mono" classifies strict functions on partial
  2311 orders.  With strict functions on linear orders, reasoning about
  2312 (in)equalities is facilitated by theorems "strict_mono_eq",
  2313 "strict_mono_less_eq" and "strict_mono_less".
  2314 
  2315 * Some set operations are now proper qualified constants with
  2316 authentic syntax.  INCOMPATIBILITY:
  2317 
  2318     op Int ~>   Set.Int
  2319     op Un ~>    Set.Un
  2320     INTER ~>    Set.INTER
  2321     UNION ~>    Set.UNION
  2322     Inter ~>    Set.Inter
  2323     Union ~>    Set.Union
  2324     {} ~>       Set.empty
  2325     UNIV ~>     Set.UNIV
  2326 
  2327 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  2328 theory Set.
  2329 
  2330 * Auxiliary class "itself" has disappeared -- classes without any
  2331 parameter are treated as expected by the 'class' command.
  2332 
  2333 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  2334 
  2335 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  2336 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  2337 
  2338 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  2339 method "approximation".  It proves formulas on real values by using
  2340 interval arithmetic.  In the formulas are also the transcendental
  2341 functions sin, cos, tan, atan, ln, exp and the constant pi are
  2342 allowed. For examples see
  2343 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  2344 
  2345 * Theory "Reflection" now resides in HOL/Library.
  2346 
  2347 * Entry point to Word library now simply named "Word".
  2348 INCOMPATIBILITY.
  2349 
  2350 * Made source layout more coherent with logical distribution
  2351 structure:
  2352 
  2353     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  2354     src/HOL/Library/Code_Message.thy ~> src/HOL/
  2355     src/HOL/Library/GCD.thy ~> src/HOL/
  2356     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  2357     src/HOL/Library/Parity.thy ~> src/HOL/
  2358     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  2359     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  2360     src/HOL/Real/Lubs.thy ~> src/HOL/
  2361     src/HOL/Real/PReal.thy ~> src/HOL/
  2362     src/HOL/Real/Rational.thy ~> src/HOL/
  2363     src/HOL/Real/RComplete.thy ~> src/HOL/
  2364     src/HOL/Real/RealDef.thy ~> src/HOL/
  2365     src/HOL/Real/RealPow.thy ~> src/HOL/
  2366     src/HOL/Real/Real.thy ~> src/HOL/
  2367     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  2368     src/HOL/Complex/Complex.thy ~> src/HOL/
  2369     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  2370     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  2371     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  2372     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  2373     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  2374     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  2375     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  2376     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  2377     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  2378     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  2379     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  2380     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  2381     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  2382     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  2383     src/HOL/Real/Float ~> src/HOL/Library/
  2384     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  2385     src/HOL/Real/RealVector.thy ~> src/HOL/
  2386 
  2387     src/HOL/arith_data.ML ~> src/HOL/Tools
  2388     src/HOL/hologic.ML ~> src/HOL/Tools
  2389     src/HOL/simpdata.ML ~> src/HOL/Tools
  2390     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  2391     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  2392     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  2393     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  2394     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  2395     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  2396     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  2397 
  2398     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  2399     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  2400     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  2401     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  2402     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  2403     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  2404 
  2405 * If methods "eval" and "evaluation" encounter a structured proof
  2406 state with !!/==>, only the conclusion is evaluated to True (if
  2407 possible), avoiding strange error messages.
  2408 
  2409 * Method "sizechange" automates termination proofs using (a
  2410 modification of) the size-change principle.  Requires SAT solver.  See
  2411 src/HOL/ex/Termination.thy for examples.
  2412 
  2413 * Simplifier: simproc for let expressions now unfolds if bound
  2414 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  2415 
  2416 * Method "arith": Linear arithmetic now ignores all inequalities when
  2417 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  2418 
  2419 * New attribute "arith" for facts that should always be used
  2420 automatically by arithmetic. It is intended to be used locally in
  2421 proofs, e.g.
  2422 
  2423   assumes [arith]: "x > 0"
  2424 
  2425 Global usage is discouraged because of possible performance impact.
  2426 
  2427 * New classes "top" and "bot" with corresponding operations "top" and
  2428 "bot" in theory Orderings; instantiation of class "complete_lattice"
  2429 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  2430 
  2431 * Changed definition lemma "less_fun_def" in order to provide an
  2432 instance for preorders on functions; use lemma "less_le" instead.
  2433 INCOMPATIBILITY.
  2434 
  2435 * Theory Orderings: class "wellorder" moved here, with explicit
  2436 induction rule "less_induct" as assumption.  For instantiation of
  2437 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  2438 INCOMPATIBILITY.
  2439 
  2440 * Theory Orderings: added class "preorder" as superclass of "order".
  2441 INCOMPATIBILITY: Instantiation proofs for order, linorder
  2442 etc. slightly changed.  Some theorems named order_class.* now named
  2443 preorder_class.*.
  2444 
  2445 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  2446 "diag" to "Id_on".
  2447 
  2448 * Theory Finite_Set: added a new fold combinator of type
  2449 
  2450   ('a => 'b => 'b) => 'b => 'a set => 'b
  2451 
  2452 Occasionally this is more convenient than the old fold combinator
  2453 which is now defined in terms of the new one and renamed to
  2454 fold_image.
  2455 
  2456 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  2457 and "ring_simps" have been replaced by "algebra_simps" (which can be
  2458 extended with further lemmas!).  At the moment both still exist but
  2459 the former will disappear at some point.
  2460 
  2461 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  2462 class recpower.  Type-specific simp rules for various recpower types
  2463 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  2464 
  2465 rat_power_0    -> power_0
  2466 rat_power_Suc  -> power_Suc
  2467 realpow_0      -> power_0
  2468 realpow_Suc    -> power_Suc
  2469 complexpow_0   -> power_0
  2470 complexpow_Suc -> power_Suc
  2471 power_poly_0   -> power_0
  2472 power_poly_Suc -> power_Suc
  2473 
  2474 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  2475 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  2476 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  2477 of lemmas from Divides has been generalized from nat to class
  2478 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  2479 renames resulting from duplicate elimination:
  2480 
  2481     dvd_def_mod ~>          dvd_eq_mod_eq_0
  2482     zero_dvd_iff ~>         dvd_0_left_iff
  2483     dvd_0 ~>                dvd_0_right
  2484     DIVISION_BY_ZERO_DIV ~> div_by_0
  2485     DIVISION_BY_ZERO_MOD ~> mod_by_0
  2486     mult_div ~>             div_mult_self2_is_id
  2487     mult_mod ~>             mod_mult_self2_is_0
  2488 
  2489 * Theory IntDiv: removed many lemmas that are instances of class-based
  2490 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  2491 rename old lemmas as follows:
  2492 
  2493 dvd_diff               -> nat_dvd_diff
  2494 dvd_zminus_iff         -> dvd_minus_iff
  2495 mod_add1_eq            -> mod_add_eq
  2496 mod_mult1_eq           -> mod_mult_right_eq
  2497 mod_mult1_eq'          -> mod_mult_left_eq
  2498 mod_mult_distrib_mod   -> mod_mult_eq
  2499 nat_mod_add_left_eq    -> mod_add_left_eq
  2500 nat_mod_add_right_eq   -> mod_add_right_eq
  2501 nat_mod_div_trivial    -> mod_div_trivial
  2502 nat_mod_mod_trivial    -> mod_mod_trivial
  2503 zdiv_zadd_self1        -> div_add_self1
  2504 zdiv_zadd_self2        -> div_add_self2
  2505 zdiv_zmult_self1       -> div_mult_self2_is_id
  2506 zdiv_zmult_self2       -> div_mult_self1_is_id
  2507 zdvd_triv_left         -> dvd_triv_left
  2508 zdvd_triv_right        -> dvd_triv_right
  2509 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  2510 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  2511 zmod_zadd_left_eq      -> mod_add_left_eq
  2512 zmod_zadd_right_eq     -> mod_add_right_eq
  2513 zmod_zadd_self1        -> mod_add_self1
  2514 zmod_zadd_self2        -> mod_add_self2
  2515 zmod_zadd1_eq          -> mod_add_eq
  2516 zmod_zdiff1_eq         -> mod_diff_eq
  2517 zmod_zdvd_zmod         -> mod_mod_cancel
  2518 zmod_zmod_cancel       -> mod_mod_cancel
  2519 zmod_zmult_self1       -> mod_mult_self2_is_0
  2520 zmod_zmult_self2       -> mod_mult_self1_is_0
  2521 zmod_1                 -> mod_by_1
  2522 zdiv_1                 -> div_by_1
  2523 zdvd_abs1              -> abs_dvd_iff
  2524 zdvd_abs2              -> dvd_abs_iff
  2525 zdvd_refl              -> dvd_refl
  2526 zdvd_trans             -> dvd_trans
  2527 zdvd_zadd              -> dvd_add
  2528 zdvd_zdiff             -> dvd_diff
  2529 zdvd_zminus_iff        -> dvd_minus_iff
  2530 zdvd_zminus2_iff       -> minus_dvd_iff
  2531 zdvd_zmultD            -> dvd_mult_right
  2532 zdvd_zmultD2           -> dvd_mult_left
  2533 zdvd_zmult_mono        -> mult_dvd_mono
  2534 zdvd_0_right           -> dvd_0_right
  2535 zdvd_0_left            -> dvd_0_left_iff
  2536 zdvd_1_left            -> one_dvd
  2537 zminus_dvd_iff         -> minus_dvd_iff
  2538 
  2539 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  2540 
  2541 * The real numbers offer decimal input syntax: 12.34 is translated
  2542 into 1234/10^2. This translation is not reversed upon output.
  2543 
  2544 * Theory Library/Polynomial defines an abstract type 'a poly of
  2545 univariate polynomials with coefficients of type 'a.  In addition to
  2546 the standard ring operations, it also supports div and mod.  Code
  2547 generation is also supported, using list-style constructors.
  2548 
  2549 * Theory Library/Inner_Product defines a class of real_inner for real
  2550 inner product spaces, with an overloaded operation inner :: 'a => 'a
  2551 => real.  Class real_inner is a subclass of real_normed_vector from
  2552 theory RealVector.
  2553 
  2554 * Theory Library/Product_Vector provides instances for the product
  2555 type 'a * 'b of several classes from RealVector and Inner_Product.
  2556 Definitions of addition, subtraction, scalar multiplication, norms,
  2557 and inner products are included.
  2558 
  2559 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  2560 addition to the field operations, numerals and case syntax are also
  2561 supported.
  2562 
  2563 * Theory Library/Diagonalize provides constructive version of Cantor's
  2564 first diagonalization argument.
  2565 
  2566 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  2567 zlcm (for int); carried together from various gcd/lcm developements in
  2568 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  2569 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  2570 may recover tupled syntax as follows:
  2571 
  2572     hide (open) const gcd
  2573     abbreviation gcd where
  2574       "gcd == (%(a, b). GCD.gcd a b)"
  2575     notation (output)
  2576       GCD.gcd ("gcd '(_, _')")
  2577 
  2578 The same works for lcm, zgcd, zlcm.
  2579 
  2580 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  2581 instantiations for algebraic structures.  Removed some duplicate
  2582 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  2583 
  2584 * ML antiquotation @{code} takes a constant as argument and generates
  2585 corresponding code in background and inserts name of the corresponding
  2586 resulting ML value/function/datatype constructor binding in place.
  2587 All occurrences of @{code} with a single ML block are generated
  2588 simultaneously.  Provides a generic and safe interface for
  2589 instrumentalizing code generation.  See
  2590 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  2591 In future you ought to refrain from ad-hoc compiling generated SML
  2592 code on the ML toplevel.  Note that (for technical reasons) @{code}
  2593 cannot refer to constants for which user-defined serializations are
  2594 set.  Refer to the corresponding ML counterpart directly in that
  2595 cases.
  2596 
  2597 * Command 'rep_datatype': instead of theorem names the command now
  2598 takes a list of terms denoting the constructors of the type to be
  2599 represented as datatype.  The characteristic theorems have to be
  2600 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  2601 have disappeared in favour of existing ones:
  2602 
  2603     unit_induct                 ~> unit.induct
  2604     prod_induct                 ~> prod.induct
  2605     sum_induct                  ~> sum.induct
  2606     Suc_Suc_eq                  ~> nat.inject
  2607     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  2608 
  2609 
  2610 *** HOL-Algebra ***
  2611 
  2612 * New locales for orders and lattices where the equivalence relation
  2613 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  2614 locales use a record structure with field eq for the equivalence.
  2615 
  2616 * New theory of factorial domains.
  2617 
  2618 * Units_l_inv and Units_r_inv are now simp rules by default.
  2619 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  2620 and/or r_inv will now also require deletion of these lemmas.
  2621 
  2622 * Renamed the following theorems, INCOMPATIBILITY:
  2623 
  2624 UpperD ~> Upper_memD
  2625 LowerD ~> Lower_memD
  2626 least_carrier ~> least_closed
  2627 greatest_carrier ~> greatest_closed
  2628 greatest_Lower_above ~> greatest_Lower_below
  2629 one_zero ~> carrier_one_zero
  2630 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  2631 
  2632 
  2633 *** HOL-Nominal ***
  2634 
  2635 * Nominal datatypes can now contain type-variables.
  2636 
  2637 * Commands 'nominal_inductive' and 'equivariance' work with local
  2638 theory targets.
  2639 
  2640 * Nominal primrec can now works with local theory targets and its
  2641 specification syntax now conforms to the general format as seen in
  2642 'inductive' etc.
  2643 
  2644 * Method "perm_simp" honours the standard simplifier attributes
  2645 (no_asm), (no_asm_use) etc.
  2646 
  2647 * The new predicate #* is defined like freshness, except that on the
  2648 left hand side can be a set or list of atoms.
  2649 
  2650 * Experimental command 'nominal_inductive2' derives strong induction
  2651 principles for inductive definitions.  In contrast to
  2652 'nominal_inductive', which can only deal with a fixed number of
  2653 binders, it can deal with arbitrary expressions standing for sets of
  2654 atoms to be avoided.  The only inductive definition we have at the
  2655 moment that needs this generalisation is the typing rule for Lets in
  2656 the algorithm W:
  2657 
  2658  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  2659  -----------------------------------------------------------------
  2660          Gamma |- Let x be t1 in t2 : T2
  2661 
  2662 In this rule one wants to avoid all the binders that are introduced by
  2663 "close Gamma T1".  We are looking for other examples where this
  2664 feature might be useful.  Please let us know.
  2665 
  2666 
  2667 *** HOLCF ***
  2668 
  2669 * Reimplemented the simplification procedure for proving continuity
  2670 subgoals.  The new simproc is extensible; users can declare additional
  2671 continuity introduction rules with the attribute [cont2cont].
  2672 
  2673 * The continuity simproc now uses a different introduction rule for
  2674 solving continuity subgoals on terms with lambda abstractions.  In
  2675 some rare cases the new simproc may fail to solve subgoals that the
  2676 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  2677 Potential INCOMPATIBILITY.
  2678 
  2679 * Command 'fixrec': specification syntax now conforms to the general
  2680 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  2681 examples.  INCOMPATIBILITY.
  2682 
  2683 
  2684 *** ZF ***
  2685 
  2686 * Proof of Zorn's Lemma for partial orders.
  2687 
  2688 
  2689 *** ML ***
  2690 
  2691 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  2692 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  2693 depends on multithreading, so timouts will not work before Poly/ML
  2694 5.2.1!
  2695 
  2696 * High-level support for concurrent ML programming, see
  2697 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  2698 particularly convenient to organize independent functional
  2699 computations.  The concept of "synchronized variables" provides a
  2700 higher-order interface for components with shared state, avoiding the
  2701 delicate details of mutexes and condition variables.  (Requires
  2702 Poly/ML 5.2.1 or later.)
  2703 
  2704 * ML bindings produced via Isar commands are stored within the Isar
  2705 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2706 become thread-safe and work with undo as expected (concerning
  2707 top-level bindings, not side-effects on global references).
  2708 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2709 compiler at runtime; really global bindings need to be given outside a
  2710 theory.  (Requires Poly/ML 5.2 or later.)
  2711 
  2712 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2713 context.  Top-level ML bindings are stored within the proof context in
  2714 a purely sequential fashion, disregarding the nested proof structure.
  2715 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2716 proof.  (Requires Poly/ML 5.2 or later.)
  2717 
  2718 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2719 and Method.setup, as well as Isar commands 'attribute_setup' and
  2720 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2721 existing code accordingly, or use plain 'setup' together with old
  2722 Method.add_method.
  2723 
  2724 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2725 to 'a -> thm, while results are always tagged with an authentic oracle
  2726 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2727 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2728 accordingly.  Note that extra performance may be gained by producing
  2729 the cterm carefully, avoiding slow Thm.cterm_of.
  2730 
  2731 * Simplified interface for defining document antiquotations via
  2732 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2733 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2734 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2735 examples.
  2736 
  2737 * More systematic treatment of long names, abstract name bindings, and
  2738 name space operations.  Basic operations on qualified names have been
  2739 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2740 Long_Name.append.  Old type bstring has been mostly replaced by
  2741 abstract type binding (see structure Binding), which supports precise
  2742 qualification by packages and local theory targets, as well as proper
  2743 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2744 bstring values into Binding.name, or better pass through abstract
  2745 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2746 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2747 
  2748 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2749 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2750 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2751 
  2752 * Disposed old type and term read functions (Sign.read_def_typ,
  2753 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2754 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2755 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2756 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2757 resort for legacy applications.
  2758 
  2759 * Disposed old declarations, tactics, tactic combinators that refer to
  2760 the simpset or claset of an implicit theory (such as Addsimps,
  2761 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2762 embedded ML text, or local_simpset_of with a proper context passed as
  2763 explicit runtime argument.
  2764 
  2765 * Rules and tactics that read instantiations (read_instantiate,
  2766 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2767 context, which is required for parsing and type-checking.  Moreover,
  2768 the variables are specified as plain indexnames, not string encodings
  2769 thereof.  INCOMPATIBILITY.
  2770 
  2771 * Generic Toplevel.add_hook interface allows to analyze the result of
  2772 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2773 for theorem dependency output of transactions resulting in a new
  2774 theory state.
  2775 
  2776 * ML antiquotations: block-structured compilation context indicated by
  2777 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2778 
  2779   @{binding name}                         - basic name binding
  2780   @{let ?pat = term}                      - term abbreviation (HO matching)
  2781   @{note name = fact}                     - fact abbreviation
  2782   @{thm fact}                             - singleton fact (with attributes)
  2783   @{thms fact}                            - general fact (with attributes)
  2784   @{lemma prop by method}                 - singleton goal
  2785   @{lemma prop by meth1 meth2}            - singleton goal
  2786   @{lemma prop1 ... propN by method}      - general goal
  2787   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2788   @{lemma (open) ...}                     - open derivation
  2789 
  2790 
  2791 *** System ***
  2792 
  2793 * The Isabelle "emacs" tool provides a specific interface to invoke
  2794 Proof General / Emacs, with more explicit failure if that is not
  2795 installed (the old isabelle-interface script silently falls back on
  2796 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2797 installation location of the Proof General distribution.
  2798 
  2799 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2800 the Isabelle process into a JVM/Scala application.  See
  2801 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2802 process wrapper has been discontinued.)
  2803 
  2804 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2805 
  2806 * Various status messages (with exact source position information) are
  2807 emitted, if proper markup print mode is enabled.  This allows
  2808 user-interface components to provide detailed feedback on internal
  2809 prover operations.
  2810 
  2811 
  2812 
  2813 New in Isabelle2008 (June 2008)
  2814 -------------------------------
  2815 
  2816 *** General ***
  2817 
  2818 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2819 and updated, with formally checked references as hyperlinks.
  2820 
  2821 * Theory loader: use_thy (and similar operations) no longer set the
  2822 implicit ML context, which was occasionally hard to predict and in
  2823 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2824 provides a proper context already.
  2825 
  2826 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2827 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2828 'use' within a theory file will do the job.
  2829 
  2830 * Name space merge now observes canonical order, i.e. the second space
  2831 is inserted into the first one, while existing entries in the first
  2832 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2833 swap theory imports.
  2834 
  2835 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2836 INCOMPATIBILITY in identifier syntax etc.
  2837 
  2838 * Outer syntax: string tokens no longer admit escaped white space,
  2839 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2840 white space without escapes.
  2841 
  2842 * Outer syntax: string tokens may contain arbitrary character codes
  2843 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2844 "foo_bar".
  2845 
  2846 
  2847 *** Pure ***
  2848 
  2849 * Context-dependent token translations.  Default setup reverts locally
  2850 fixed variables, and adds hilite markup for undeclared frees.
  2851 
  2852 * Unused theorems can be found using the new command 'unused_thms'.
  2853 There are three ways of invoking it:
  2854 
  2855 (1) unused_thms
  2856      Only finds unused theorems in the current theory.
  2857 
  2858 (2) unused_thms thy_1 ... thy_n -
  2859      Finds unused theorems in the current theory and all of its ancestors,
  2860      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2861 
  2862 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2863      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2864      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2865      their ancestors.
  2866 
  2867 In order to increase the readability of the list produced by
  2868 unused_thms, theorems that have been created by a particular instance
  2869 of a theory command such as 'inductive' or 'function' are considered
  2870 to belong to the same "group", meaning that if at least one theorem in
  2871 this group is used, the other theorems in the same group are no longer
  2872 reported as unused.  Moreover, if all theorems in the group are
  2873 unused, only one theorem in the group is displayed.
  2874 
  2875 Note that proof objects have to be switched on in order for
  2876 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2877 usually the case when using Proof General with the default settings).
  2878 
  2879 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2880 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2881 duplicate fact bindings, or even accidental fact duplications.  Note
  2882 that tools may maintain dynamically scoped facts systematically, using
  2883 PureThy.add_thms_dynamic.
  2884 
  2885 * Command 'hide' now allows to hide from "fact" name space as well.
  2886 
  2887 * Eliminated destructive theorem database, simpset, claset, and
  2888 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2889 update of theories within ML code.
  2890 
  2891 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2892 INCOMPATIBILITY, object-logics depending on former Pure require
  2893 additional setup PureThy.old_appl_syntax_setup; object-logics
  2894 depending on former CPure need to refer to Pure.
  2895 
  2896 * Commands 'use' and 'ML' are now purely functional, operating on
  2897 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2898 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2899 INCOMPATIBILITY.
  2900 
  2901 * Command 'setup': discontinued implicit version with ML reference.
  2902 
  2903 * Instantiation target allows for simultaneous specification of class
  2904 instance operations together with an instantiation proof.
  2905 Type-checking phase allows to refer to class operations uniformly.
  2906 See src/HOL/Complex/Complex.thy for an Isar example and
  2907 src/HOL/Library/Eval.thy for an ML example.
  2908 
  2909 * Indexing of literal facts: be more serious about including only
  2910 facts from the visible specification/proof context, but not the
  2911 background context (locale etc.).  Affects `prop` notation and method
  2912 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2913 situations.
  2914 
  2915 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2916 "(open)" option, which used to expose internal bound variables to the
  2917 proof text.
  2918 
  2919 * Isar statements: removed obsolete case "rule_context".
  2920 INCOMPATIBILITY, better use explicit fixes/assumes.
  2921 
  2922 * Locale proofs: default proof step now includes 'unfold_locales';
  2923 hence 'proof' without argument may be used to unfold locale
  2924 predicates.
  2925 
  2926 
  2927 *** Document preparation ***
  2928 
  2929 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2930 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2931 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2932 spot); renamed link color from "darkblue" to "linkcolor" (default
  2933 value unchanged, can be redefined via \definecolor); no longer sets
  2934 "a4paper" option (unnecessary or even intrusive).
  2935 
  2936 * Antiquotation @{lemma A method} proves proposition A by the given
  2937 method (either a method name or a method name plus (optional) method
  2938 arguments in parentheses) and prints A just like @{prop A}.
  2939 
  2940 
  2941 *** HOL ***
  2942 
  2943 * New primrec package.  Specification syntax conforms in style to
  2944 definition/function/....  No separate induction rule is provided.  The
  2945 "primrec" command distinguishes old-style and new-style specifications
  2946 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2947 When adjusting theories, beware: constants stemming from new-style
  2948 primrec specifications have authentic syntax.
  2949 
  2950 * Metis prover is now an order of magnitude faster, and also works
  2951 with multithreading.
  2952 
  2953 * Metis: the maximum number of clauses that can be produced from a
  2954 theorem is now given by the attribute max_clauses.  Theorems that
  2955 exceed this number are ignored, with a warning printed.
  2956 
  2957 * Sledgehammer no longer produces structured proofs by default. To
  2958 enable, declare [[sledgehammer_full = true]].  Attributes
  2959 reconstruction_modulus, reconstruction_sorts renamed
  2960 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2961 
  2962 * Method "induct_scheme" derives user-specified induction rules
  2963 from well-founded induction and completeness of patterns. This factors
  2964 out some operations that are done internally by the function package
  2965 and makes them available separately.  See
  2966 src/HOL/ex/Induction_Scheme.thy for examples.
  2967 
  2968 * More flexible generation of measure functions for termination
  2969 proofs: Measure functions can be declared by proving a rule of the
  2970 form "is_measure f" and giving it the [measure_function] attribute.
  2971 The "is_measure" predicate is logically meaningless (always true), and
  2972 just guides the heuristic.  To find suitable measure functions, the
  2973 termination prover sets up the goal "is_measure ?f" of the appropriate
  2974 type and generates all solutions by prolog-style backwards proof using
  2975 the declared rules.
  2976 
  2977 This setup also deals with rules like 
  2978 
  2979   "is_measure f ==> is_measure (list_size f)"
  2980 
  2981 which accommodates nested datatypes that recurse through lists.
  2982 Similar rules are predeclared for products and option types.
  2983 
  2984 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  2985 
  2986   INCOMPATIBILITIES:
  2987 
  2988   - Definitions of overloaded constants on sets have to be replaced by
  2989     definitions on => and bool.
  2990 
  2991   - Some definitions of overloaded operators on sets can now be proved
  2992     using the definitions of the operators on => and bool.  Therefore,
  2993     the following theorems have been renamed:
  2994 
  2995       subset_def   -> subset_eq
  2996       psubset_def  -> psubset_eq
  2997       set_diff_def -> set_diff_eq
  2998       Compl_def    -> Compl_eq
  2999       Sup_set_def  -> Sup_set_eq
  3000       Inf_set_def  -> Inf_set_eq
  3001       sup_set_def  -> sup_set_eq
  3002       inf_set_def  -> inf_set_eq
  3003 
  3004   - Due to the incompleteness of the HO unification algorithm, some
  3005     rules such as subst may require manual instantiation, if some of
  3006     the unknowns in the rule is a set.
  3007 
  3008   - Higher order unification and forward proofs:
  3009     The proof pattern
  3010 
  3011       have "P (S::'a set)" <...>
  3012       then have "EX S. P S" ..
  3013 
  3014     no longer works (due to the incompleteness of the HO unification
  3015     algorithm) and must be replaced by the pattern
  3016 
  3017       have "EX S. P S"
  3018       proof
  3019         show "P S" <...>
  3020       qed
  3021 
  3022   - Calculational reasoning with subst (or similar rules):
  3023     The proof pattern
  3024 
  3025       have "P (S::'a set)" <...>
  3026       also have "S = T" <...>
  3027       finally have "P T" .
  3028 
  3029     no longer works (for similar reasons as the previous example) and
  3030     must be replaced by something like
  3031 
  3032       have "P (S::'a set)" <...>
  3033       moreover have "S = T" <...>
  3034       ultimately have "P T" by simp
  3035 
  3036   - Tactics or packages written in ML code:
  3037     Code performing pattern matching on types via
  3038 
  3039       Type ("set", [T]) => ...
  3040 
  3041     must be rewritten. Moreover, functions like strip_type or
  3042     binder_types no longer return the right value when applied to a
  3043     type of the form
  3044 
  3045       T1 => ... => Tn => U => bool
  3046 
  3047     rather than
  3048 
  3049       T1 => ... => Tn => U set
  3050 
  3051 * Merged theories Wellfounded_Recursion, Accessible_Part and
  3052 Wellfounded_Relations to theory Wellfounded.
  3053 
  3054 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  3055 
  3056 * Class finite no longer treats UNIV as class parameter.  Use class
  3057 enum from theory Library/Enum instead to achieve a similar effect.
  3058 INCOMPATIBILITY.
  3059 
  3060 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  3061 and "Cons".  INCOMPATIBILITY.
  3062 
  3063 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  3064 Potential INCOMPATIBILITY.
  3065 
  3066 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  3067 injective_fst_snd removed, use split_eta and prod_eqI instead.
  3068 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  3069 
  3070 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  3071 the same name in theory Orderings:
  3072 
  3073   less_trans
  3074   less_linear
  3075   le_imp_less_or_eq
  3076   le_less_trans
  3077   less_le_trans
  3078   less_not_sym
  3079   less_asym
  3080 
  3081 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  3082 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  3083 and different variable names.
  3084 
  3085 * Library/Option_ord.thy: Canonical order on option type.
  3086 
  3087 * Library/RBT.thy: Red-black trees, an efficient implementation of
  3088 finite maps.
  3089 
  3090 * Library/Countable.thy: Type class for countable types.
  3091 
  3092 * Theory Int: The representation of numerals has changed.  The infix
  3093 operator BIT and the bit datatype with constructors B0 and B1 have
  3094 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  3095 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  3096 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  3097 accordingly.
  3098 
  3099 * Theory Nat: definition of <= and < on natural numbers no longer
  3100 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  3101 le_def and less_def have disappeared.  Consider lemmas not_less
  3102 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  3103 
  3104 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  3105 (whose purpose mainly is for various fold_set functionals) have been
  3106 abandoned in favor of the existing algebraic classes
  3107 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  3108 lower_semilattice (resp. upper_semilattice) and linorder.
  3109 INCOMPATIBILITY.
  3110 
  3111 * Theory Transitive_Closure: induct and cases rules now declare proper
  3112 case_names ("base" and "step").  INCOMPATIBILITY.
  3113 
  3114 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  3115 lattices.  The form set-specific version is available as
  3116 Inductive.lfp_ordinal_induct_set.
  3117 
  3118 * Renamed theorems "power.simps" to "power_int.simps".
  3119 INCOMPATIBILITY.
  3120 
  3121 * Class semiring_div provides basic abstract properties of semirings
  3122 with division and modulo operations.  Subsumes former class dvd_mod.
  3123 
  3124 * Merged theories IntDef, Numeral and IntArith into unified theory
  3125 Int.  INCOMPATIBILITY.
  3126 
  3127 * Theory Library/Code_Index: type "index" now represents natural
  3128 numbers rather than integers.  INCOMPATIBILITY.
  3129 
  3130 * New class "uminus" with operation "uminus" (split of from class
  3131 "minus" which now only has operation "minus", binary).
  3132 INCOMPATIBILITY.
  3133 
  3134 * Constants "card", "internal_split", "option_map" now with authentic
  3135 syntax.  INCOMPATIBILITY.
  3136 
  3137 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  3138 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  3139 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  3140 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  3141 Sup_set_def, le_def, less_def, option_map_def now with object
  3142 equality.  INCOMPATIBILITY.
  3143 
  3144 * Records. Removed K_record, and replaced it by pure lambda term
  3145 %x. c. The simplifier setup is now more robust against eta expansion.
  3146 INCOMPATIBILITY: in cases explicitly referring to K_record.
  3147 
  3148 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  3149 
  3150 * Library/ListVector: new theory of arithmetic vector operations.
  3151 
  3152 * Library/Order_Relation: new theory of various orderings as sets of
  3153 pairs.  Defines preorders, partial orders, linear orders and
  3154 well-orders on sets and on types.
  3155 
  3156 
  3157 *** ZF ***
  3158 
  3159 * Renamed some theories to allow to loading both ZF and HOL in the
  3160 same session:
  3161 
  3162   Datatype  -> Datatype_ZF
  3163   Inductive -> Inductive_ZF
  3164   Int       -> Int_ZF
  3165   IntDiv    -> IntDiv_ZF
  3166   Nat       -> Nat_ZF
  3167   List      -> List_ZF
  3168   Main      -> Main_ZF
  3169 
  3170 INCOMPATIBILITY: ZF theories that import individual theories below
  3171 Main might need to be adapted.  Regular theory Main is still
  3172 available, as trivial extension of Main_ZF.
  3173 
  3174 
  3175 *** ML ***
  3176 
  3177 * ML within Isar: antiquotation @{const name} or @{const
  3178 name(typargs)} produces statically-checked Const term.
  3179 
  3180 * Functor NamedThmsFun: data is available to the user as dynamic fact
  3181 (of the same name).  Removed obsolete print command.
  3182 
  3183 * Removed obsolete "use_legacy_bindings" function.
  3184 
  3185 * The ``print mode'' is now a thread-local value derived from a global
  3186 template (the former print_mode reference), thus access becomes
  3187 non-critical.  The global print_mode reference is for session
  3188 management only; user-code should use print_mode_value,
  3189 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  3190 
  3191 * Functions system/system_out provide a robust way to invoke external
  3192 shell commands, with propagation of interrupts (requires Poly/ML
  3193 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  3194 
  3195 
  3196 *** System ***
  3197 
  3198 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  3199 in accordance with Proof General 3.7, which prefers GNU emacs.
  3200 
  3201 * isatool tty runs Isabelle process with plain tty interaction;
  3202 optional line editor may be specified via ISABELLE_LINE_EDITOR
  3203 setting, the default settings attempt to locate "ledit" and "rlwrap".
  3204 
  3205 * isatool browser now works with Cygwin as well, using general
  3206 "javapath" function defined in Isabelle process environment.
  3207 
  3208 * YXML notation provides a simple and efficient alternative to
  3209 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  3210 isatool yxml as described in the Isabelle system manual.
  3211 
  3212 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  3213 provides general wrapper for managing an Isabelle process in a robust
  3214 fashion, with ``cooked'' output from stdin/stderr.
  3215 
  3216 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  3217 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  3218 
  3219 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  3220 way of changing the user's settings is via
  3221 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  3222 script.
  3223 
  3224 * Multithreading.max_threads := 0 refers to the number of actual CPU
  3225 cores of the underlying machine, which is a good starting point for
  3226 optimal performance tuning.  The corresponding usedir option -M allows
  3227 "max" as an alias for "0".  WARNING: does not work on certain versions
  3228 of Mac OS (with Poly/ML 5.1).
  3229 
  3230 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  3231 adverse effect of Isabelle flooding interactive front-ends (notably
  3232 ProofGeneral / XEmacs).
  3233 
  3234 
  3235 
  3236 New in Isabelle2007 (November 2007)
  3237 -----------------------------------
  3238 
  3239 *** General ***
  3240 
  3241 * More uniform information about legacy features, notably a
  3242 warning/error of "Legacy feature: ...", depending on the state of the
  3243 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  3244 legacy features will disappear eventually.
  3245 
  3246 * Theory syntax: the header format ``theory A = B + C:'' has been
  3247 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  3248 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  3249 
  3250 * Theory syntax: the old non-Isar theory file format has been
  3251 discontinued altogether.  Note that ML proof scripts may still be used
  3252 with Isar theories; migration is usually quite simple with the ML
  3253 function use_legacy_bindings.  INCOMPATIBILITY.
  3254 
  3255 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  3256 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  3257 quotes.
  3258 
  3259 * Theory loader: be more serious about observing the static theory
  3260 header specifications (including optional directories), but not the
  3261 accidental file locations of previously successful loads.  The strict
  3262 update policy of former update_thy is now already performed by
  3263 use_thy, so the former has been removed; use_thys updates several
  3264 theories simultaneously, just as 'imports' within a theory header
  3265 specification, but without merging the results.  Potential
  3266 INCOMPATIBILITY: may need to refine theory headers and commands
  3267 ROOT.ML which depend on load order.
  3268 
  3269 * Theory loader: optional support for content-based file
  3270 identification, instead of the traditional scheme of full physical
  3271 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  3272 (cf. the system manual).  The new scheme allows to work with
  3273 non-finished theories in persistent session images, such that source
  3274 files may be moved later on without requiring reloads.
  3275 
  3276 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3277 file (with the same base name as the theory) are considered a legacy
  3278 feature, which will disappear eventually. Even now, the theory loader
  3279 no longer maintains dependencies on such files.
  3280 
  3281 * Syntax: the scope for resolving ambiguities via type-inference is
  3282 now limited to individual terms, instead of whole simultaneous
  3283 specifications as before. This greatly reduces the complexity of the
  3284 syntax module and improves flexibility by separating parsing and
  3285 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  3286 'fixes' etc.) are required in rare situations.
  3287 
  3288 * Syntax: constants introduced by new-style packages ('definition',
  3289 'abbreviation' etc.) are passed through the syntax module in
  3290 ``authentic mode''. This means that associated mixfix annotations
  3291 really stick to such constants, independently of potential name space
  3292 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  3293 trees are represented slightly differently, may need to adapt syntax
  3294 translations accordingly. Use CONST marker in 'translations' and
  3295 @{const_syntax} antiquotation in 'parse_translation' etc.
  3296 
  3297 * Legacy goal package: reduced interface to the bare minimum required
  3298 to keep existing proof scripts running.  Most other user-level
  3299 functions are now part of the OldGoals structure, which is *not* open
  3300 by default (consider isatool expandshort before open OldGoals).
  3301 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  3302 these tend to cause confusion about the actual goal (!) context being
  3303 used here, which is not necessarily the same as the_context().
  3304 
  3305 * Command 'find_theorems': supports "*" wild-card in "name:"
  3306 criterion; "with_dups" option.  Certain ProofGeneral versions might
  3307 support a specific search form (see ProofGeneral/CHANGES).
  3308 
  3309 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  3310 by default, which means that "prems" (and also "fixed variables") are
  3311 suppressed from proof state output.  Note that the ProofGeneral
  3312 settings mechanism allows to change and save options persistently, but
  3313 older versions of Isabelle will fail to start up if a negative prems
  3314 limit is imposed.
  3315 
  3316 * Local theory targets may be specified by non-nested blocks of
  3317 ``context/locale/class ... begin'' followed by ``end''.  The body may
  3318 contain definitions, theorems etc., including any derived mechanism
  3319 that has been implemented on top of these primitives.  This concept
  3320 generalizes the existing ``theorem (in ...)'' towards more versatility
  3321 and scalability.
  3322 
  3323 * Proof General interface: proper undo of final 'end' command;
  3324 discontinued Isabelle/classic mode (ML proof scripts).
  3325 
  3326 
  3327 *** Document preparation ***
  3328 
  3329 * Added antiquotation @{theory name} which prints the given name,
  3330 after checking that it refers to a valid ancestor theory in the
  3331 current context.
  3332 
  3333 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  3334 check the given source text as ML type/structure, printing verbatim.
  3335 
  3336 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  3337 "c args == rhs" given in the current context.  (Any number of
  3338 arguments may be given on the LHS.)
  3339 
  3340 
  3341 *** Pure ***
  3342 
  3343 * The 'class' package offers a combination of axclass and locale to
  3344 achieve Haskell-like type classes in Isabelle.  Definitions and
  3345 theorems within a class context produce both relative results (with
  3346 implicit parameters according to the locale context), and polymorphic
  3347 constants with qualified polymorphism (according to the class
  3348 context).  Within the body context of a 'class' target, a separate
  3349 syntax layer ("user space type system") takes care of converting
  3350 between global polymorphic consts and internal locale representation.
  3351 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  3352 "isatool doc classes" provides a tutorial.
  3353 
  3354 * Generic code generator framework allows to generate executable
  3355 code for ML and Haskell (including Isabelle classes).  A short usage
  3356 sketch:
  3357 
  3358     internal compilation:
  3359         export_code <list of constants (term syntax)> in SML
  3360     writing SML code to a file:
  3361         export_code <list of constants (term syntax)> in SML <filename>
  3362     writing OCaml code to a file:
  3363         export_code <list of constants (term syntax)> in OCaml <filename>
  3364     writing Haskell code to a bunch of files:
  3365         export_code <list of constants (term syntax)> in Haskell <filename>
  3366 
  3367     evaluating closed propositions to True/False using code generation:
  3368         method ``eval''
  3369 
  3370 Reasonable default setup of framework in HOL.
  3371 
  3372 Theorem attributs for selecting and transforming function equations theorems:
  3373 
  3374     [code fun]:        select a theorem as function equation for a specific constant
  3375     [code fun del]:    deselect a theorem as function equation for a specific constant
  3376     [code inline]:     select an equation theorem for unfolding (inlining) in place
  3377     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  3378 
  3379 User-defined serializations (target in {SML, OCaml, Haskell}):
  3380 
  3381     code_const <and-list of constants (term syntax)>
  3382       {(target) <and-list of const target syntax>}+
  3383 
  3384     code_type <and-list of type constructors>
  3385       {(target) <and-list of type target syntax>}+
  3386 
  3387     code_instance <and-list of instances>
  3388       {(target)}+
  3389         where instance ::= <type constructor> :: <class>
  3390 
  3391     code_class <and_list of classes>
  3392       {(target) <and-list of class target syntax>}+
  3393         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  3394 
  3395 code_instance and code_class only are effective to target Haskell.
  3396 
  3397 For example usage see src/HOL/ex/Codegenerator.thy and
  3398 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  3399 generation from Isabelle/HOL theories is available via "isatool doc
  3400 codegen".
  3401 
  3402 * Code generator: consts in 'consts_code' Isar commands are now
  3403 referred to by usual term syntax (including optional type
  3404 annotations).
  3405 
  3406 * Command 'no_translations' removes translation rules from theory
  3407 syntax.
  3408 
  3409 * Overloaded definitions are now actually checked for acyclic
  3410 dependencies.  The overloading scheme is slightly more general than
  3411 that of Haskell98, although Isabelle does not demand an exact
  3412 correspondence to type class and instance declarations.
  3413 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  3414 exotic versions of overloading -- at the discretion of the user!
  3415 
  3416 Polymorphic constants are represented via type arguments, i.e. the
  3417 instantiation that matches an instance against the most general
  3418 declaration given in the signature.  For example, with the declaration
  3419 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  3420 as c(nat).  Overloading is essentially simultaneous structural
  3421 recursion over such type arguments.  Incomplete specification patterns
  3422 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  3423 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  3424 Command 'print_theory' outputs the normalized system of recursive
  3425 equations, see section "definitions".
  3426 
  3427 * Configuration options are maintained within the theory or proof
  3428 context (with name and type bool/int/string), providing a very simple
  3429 interface to a poor-man's version of general context data.  Tools may
  3430 declare options in ML (e.g. using Attrib.config_int) and then refer to
  3431 these values using Config.get etc.  Users may change options via an
  3432 associated attribute of the same name.  This form of context
  3433 declaration works particularly well with commands 'declare' or
  3434 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  3435 very easy to avoid global references, which would not observe Isar
  3436 toplevel undo/redo and fail to work with multithreading.
  3437 
  3438 Various global ML references of Pure and HOL have been turned into
  3439 configuration options:
  3440 
  3441   Unify.search_bound		unify_search_bound
  3442   Unify.trace_bound		unify_trace_bound
  3443   Unify.trace_simp		unify_trace_simp
  3444   Unify.trace_types		unify_trace_types
  3445   Simplifier.simp_depth_limit	simp_depth_limit
  3446   Blast.depth_limit		blast_depth_limit
  3447   DatatypeProp.dtK		datatype_distinctness_limit
  3448   fast_arith_neq_limit  	fast_arith_neq_limit
  3449   fast_arith_split_limit	fast_arith_split_limit
  3450 
  3451 * Named collections of theorems may be easily installed as context
  3452 data using the functor NamedThmsFun (see also
  3453 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  3454 attributes; there is also a toplevel print command.  This facility is
  3455 just a common case of general context data, which is the preferred way
  3456 for anything more complex than just a list of facts in canonical
  3457 order.
  3458 
  3459 * Isar: command 'declaration' augments a local theory by generic
  3460 declaration functions written in ML.  This enables arbitrary content
  3461 being added to the context, depending on a morphism that tells the
  3462 difference of the original declaration context wrt. the application
  3463 context encountered later on.
  3464 
  3465 * Isar: proper interfaces for simplification procedures.  Command
  3466 'simproc_setup' declares named simprocs (with match patterns, and body
  3467 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  3468 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  3469 
  3470 * Isar: an extra pair of brackets around attribute declarations
  3471 abbreviates a theorem reference involving an internal dummy fact,
  3472 which will be ignored later --- only the effect of the attribute on
  3473 the background context will persist.  This form of in-place
  3474 declarations is particularly useful with commands like 'declare' and
  3475 'using', for example ``have A using [[simproc a]] by simp''.
  3476 
  3477 * Isar: method "assumption" (and implicit closing of subproofs) now
  3478 takes simple non-atomic goal assumptions into account: after applying
  3479 an assumption as a rule the resulting subgoals are solved by atomic
  3480 assumption steps.  This is particularly useful to finish 'obtain'
  3481 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  3482 without referring to the original premise "!!x. P x ==> thesis" in the
  3483 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  3484 more permissive.
  3485 
  3486 * Isar: implicit use of prems from the Isar proof context is
  3487 considered a legacy feature.  Common applications like ``have A .''
  3488 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  3489 referencing facts explicitly here improves readability and
  3490 maintainability of proof texts.
  3491 
  3492 * Isar: improper proof element 'guess' is like 'obtain', but derives
  3493 the obtained context from the course of reasoning!  For example:
  3494 
  3495   assume "EX x y. A x & B y"   -- "any previous fact"
  3496   then guess x and y by clarify
  3497 
  3498 This technique is potentially adventurous, depending on the facts and
  3499 proof tools being involved here.
  3500 
  3501 * Isar: known facts from the proof context may be specified as literal
  3502 propositions, using ASCII back-quote syntax.  This works wherever
  3503 named facts used to be allowed so far, in proof commands, proof
  3504 methods, attributes etc.  Literal facts are retrieved from the context
  3505 according to unification of type and term parameters.  For example,
  3506 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  3507 theorems in the current context, then these are valid literal facts:
  3508 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  3509 
  3510 There is also a proof method "fact" which does the same composition
  3511 for explicit goal states, e.g. the following proof texts coincide with
  3512 certain special cases of literal facts:
  3513 
  3514   have "A" by fact                 ==  note `A`
  3515   have "A ==> B" by fact           ==  note `A ==> B`
  3516   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  3517   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  3518 
  3519 * Isar: ":" (colon) is no longer a symbolic identifier character in
  3520 outer syntax.  Thus symbolic identifiers may be used without
  3521 additional white space in declarations like this: ``assume *: A''.
  3522 
  3523 * Isar: 'print_facts' prints all local facts of the current context,
  3524 both named and unnamed ones.
  3525 
  3526 * Isar: 'def' now admits simultaneous definitions, e.g.:
  3527 
  3528   def x == "t" and y == "u"
  3529 
  3530 * Isar: added command 'unfolding', which is structurally similar to
  3531 'using', but affects both the goal state and facts by unfolding given
  3532 rewrite rules.  Thus many occurrences of the 'unfold' method or
  3533 'unfolded' attribute may be replaced by first-class proof text.
  3534 
  3535 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  3536 and command 'unfolding' now all support object-level equalities
  3537 (potentially conditional).  The underlying notion of rewrite rule is
  3538 analogous to the 'rule_format' attribute, but *not* that of the
  3539 Simplifier (which is usually more generous).
  3540 
  3541 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  3542 premises of a theorem by n. Useful in conjunction with drule.
  3543 
  3544 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  3545 method expression within a sandbox consisting of the first N
  3546 sub-goals, which need to exist.  For example, ``simp_all [3]''
  3547 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  3548 simplifies all new goals that emerge from applying rule foo to the
  3549 originally first one.
  3550 
  3551 * Isar: schematic goals are no longer restricted to higher-order
  3552 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  3553 expected.
  3554 
  3555 * Isar: the conclusion of a long theorem statement is now either
  3556 'shows' (a simultaneous conjunction, as before), or 'obtains'
  3557 (essentially a disjunction of cases with local parameters and
  3558 assumptions).  The latter allows to express general elimination rules
  3559 adequately; in this notation common elimination rules look like this:
  3560 
  3561   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  3562     assumes "EX x. P x"
  3563     obtains x where "P x"
  3564 
  3565   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  3566     assumes "A & B"
  3567     obtains A and B
  3568 
  3569   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  3570     assumes "A | B"
  3571     obtains
  3572       A
  3573     | B
  3574 
  3575 The subsequent classical rules even refer to the formal "thesis"
  3576 explicitly:
  3577 
  3578   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  3579     obtains "~ thesis"
  3580 
  3581   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  3582     obtains "thesis ==> something"
  3583 
  3584 The actual proof of an 'obtains' statement is analogous to that of the
  3585 Isar proof element 'obtain', only that there may be several cases.
  3586 Optional case names may be specified in parentheses; these will be
  3587 available both in the present proof and as annotations in the
  3588 resulting rule, for later use with the 'cases' method (cf. attribute
  3589 case_names).
  3590 
  3591 * Isar: the assumptions of a long theorem statement are available as
  3592 "assms" fact in the proof context.  This is more appropriate than the
  3593 (historical) "prems", which refers to all assumptions of the current
  3594 context, including those from the target locale, proof body etc.
  3595 
  3596 * Isar: 'print_statement' prints theorems from the current theory or
  3597 proof context in long statement form, according to the syntax of a
  3598 top-level lemma.
  3599 
  3600 * Isar: 'obtain' takes an optional case name for the local context
  3601 introduction rule (default "that").
  3602 
  3603 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  3604 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  3605 to occur.
  3606 
  3607 * Pure: syntax "CONST name" produces a fully internalized constant
  3608 according to the current context.  This is particularly useful for
  3609 syntax translations that should refer to internal constant
  3610 representations independently of name spaces.
  3611 
  3612 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  3613 instead of "FOO ". This allows multiple binder declarations to coexist
  3614 in the same context.  INCOMPATIBILITY.
  3615 
  3616 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  3617 primitive that also works in a locale context (both for constants and
  3618 fixed variables). Type declaration and internal syntactic representation
  3619 of given constants retrieved from the context. Likewise, the
  3620 'no_notation' command allows to remove given syntax annotations from the
  3621 current context.
  3622 
  3623 * Isar/locales: new derived specification elements 'axiomatization',
  3624 'definition', 'abbreviation', which support type-inference, admit
  3625 object-level specifications (equality, equivalence).  See also the
  3626 isar-ref manual.  Examples:
  3627 
  3628   axiomatization
  3629     eq  (infix "===" 50) where
  3630     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  3631 
  3632   definition "f x y = x + y + 1"
  3633   definition g where "g x = f x x"
  3634 
  3635   abbreviation
  3636     neq  (infix "=!=" 50) where
  3637     "x =!= y == ~ (x === y)"
  3638 
  3639 These specifications may be also used in a locale context.  Then the
  3640 constants being introduced depend on certain fixed parameters, and the
  3641 constant name is qualified by the locale base name.  An internal
  3642 abbreviation takes care for convenient input and output, making the
  3643 parameters implicit and using the original short name.  See also
  3644 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  3645 entities from a monomorphic theory.
  3646 
  3647 Presently, abbreviations are only available 'in' a target locale, but
  3648 not inherited by general import expressions.  Also note that
  3649 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  3650 'translations' in common applications.  The "no_abbrevs" print mode
  3651 prevents folding of abbreviations in term output.
  3652 
  3653 Concrete syntax is attached to specified constants in internal form,
  3654 independently of name spaces.  The parse tree representation is
  3655 slightly different -- use 'notation' instead of raw 'syntax', and
  3656 'translations' with explicit "CONST" markup to accommodate this.
  3657 
  3658 * Pure/Isar: unified syntax for new-style specification mechanisms
  3659 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  3660 full type inference and dummy patterns ("_").  For example:
  3661 
  3662   definition "K x _ = x"
  3663 
  3664   inductive conj for A B
  3665   where "A ==> B ==> conj A B"
  3666 
  3667 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  3668 the current context.  Print mode "no_abbrevs" prevents inversion of
  3669 abbreviations on output.
  3670 
  3671 * Isar/locales: improved parameter handling: use of locales "var" and
  3672 "struct" no longer necessary; - parameter renamings are no longer
  3673 required to be injective.  For example, this allows to define
  3674 endomorphisms as locale endom = homom mult mult h.
  3675 
  3676 * Isar/locales: changed the way locales with predicates are defined.
  3677 Instead of accumulating the specification, the imported expression is
  3678 now an interpretation.  INCOMPATIBILITY: different normal form of
  3679 locale expressions.  In particular, in interpretations of locales with
  3680 predicates, goals repesenting already interpreted fragments are not
  3681 removed automatically.  Use methods `intro_locales' and
  3682 `unfold_locales'; see below.
  3683 
  3684 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  3685 provide backward reasoning on locales predicates.  The methods are
  3686 aware of interpretations and discharge corresponding goals.
  3687 `intro_locales' is less aggressive then `unfold_locales' and does not
  3688 unfold predicates to assumptions.
  3689 
  3690 * Isar/locales: the order in which locale fragments are accumulated
  3691 has changed.  This enables to override declarations from fragments due
  3692 to interpretations -- for example, unwanted simp rules.
  3693 
  3694 * Isar/locales: interpretation in theories and proof contexts has been
  3695 extended.  One may now specify (and prove) equations, which are
  3696 unfolded in interpreted theorems.  This is useful for replacing
  3697 defined concepts (constants depending on locale parameters) by
  3698 concepts already existing in the target context.  Example:
  3699 
  3700   interpretation partial_order ["op <= :: [int, int] => bool"]
  3701     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3702 
  3703 Typically, the constant `partial_order.less' is created by a
  3704 definition specification element in the context of locale
  3705 partial_order.
  3706 
  3707 * Method "induct": improved internal context management to support
  3708 local fixes and defines on-the-fly. Thus explicit meta-level
  3709 connectives !!  and ==> are rarely required anymore in inductive goals
  3710 (using object-logic connectives for this purpose has been long
  3711 obsolete anyway). Common proof patterns are explained in
  3712 src/HOL/Induct/Common_Patterns.thy, see also
  3713 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3714 examples.
  3715 
  3716 * Method "induct": improved handling of simultaneous goals. Instead of
  3717 introducing object-level conjunction, the statement is now split into
  3718 several conclusions, while the corresponding symbolic cases are nested
  3719 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3720 see src/HOL/Induct/Common_Patterns.thy, for example.
  3721 
  3722 * Method "induct": mutual induction rules are now specified as a list
  3723 of rule sharing the same induction cases. HOL packages usually provide
  3724 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3725 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3726 mutual induction rules differently, i.e. like this:
  3727 
  3728   (induct rule: foo_bar.inducts)
  3729   (induct set: foo bar)
  3730   (induct pred: foo bar)
  3731   (induct type: foo bar)
  3732 
  3733 The ML function ProjectRule.projections turns old-style rules into the
  3734 new format.
  3735 
  3736 * Method "coinduct": dual of induction, see
  3737 src/HOL/Library/Coinductive_List.thy for various examples.
  3738 
  3739 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3740 considered a legacy feature.
  3741 
  3742 * Attribute "symmetric" produces result with standardized schematic
  3743 variables (index 0).  Potential INCOMPATIBILITY.
  3744 
  3745 * Simplifier: by default the simplifier trace only shows top level
  3746 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3747 default. Thus there is less danger of being flooded by the trace. The
  3748 trace indicates where parts have been suppressed.
  3749   
  3750 * Provers/classical: removed obsolete classical version of elim_format
  3751 attribute; classical elim/dest rules are now treated uniformly when
  3752 manipulating the claset.
  3753 
  3754 * Provers/classical: stricter checks to ensure that supplied intro,
  3755 dest and elim rules are well-formed; dest and elim rules must have at
  3756 least one premise.
  3757 
  3758 * Provers/classical: attributes dest/elim/intro take an optional
  3759 weight argument for the rule (just as the Pure versions).  Weights are
  3760 ignored by automated tools, but determine the search order of single
  3761 rule steps.
  3762 
  3763 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3764 where the body does not mention the bound variable.  Note that dummy
  3765 patterns implicitly depend on their context of bounds, which makes
  3766 "{_. _}" match any set comprehension as expected.  Potential
  3767 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3768 constant "_idtdummy" in the binding position.
  3769 
  3770 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3771 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3772 for example "A -> B" => "Pi A (%_. B)".
  3773 
  3774 * Pure: 'class_deps' command visualizes the subclass relation, using
  3775 the graph browser tool.
  3776 
  3777 * Pure: 'print_theory' now suppresses certain internal declarations by
  3778 default; use '!' option for full details.
  3779 
  3780 
  3781 *** HOL ***
  3782 
  3783 * Method "metis" proves goals by applying the Metis general-purpose
  3784 resolution prover (see also http://gilith.com/software/metis/).
  3785 Examples are in the directory MetisExamples.  WARNING: the
  3786 Isabelle/HOL-Metis integration does not yet work properly with
  3787 multi-threading.
  3788   
  3789 * Command 'sledgehammer' invokes external automatic theorem provers as
  3790 background processes.  It generates calls to the "metis" method if
  3791 successful. These can be pasted into the proof.  Users do not have to
  3792 wait for the automatic provers to return.  WARNING: does not really
  3793 work with multi-threading.
  3794 
  3795 * New "auto_quickcheck" feature tests outermost goal statements for
  3796 potential counter-examples.  Controlled by ML references
  3797 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3798 5000 milliseconds).  Fails silently if statements is outside of
  3799 executable fragment, or any other codgenerator problem occurs.
  3800 
  3801 * New constant "undefined" with axiom "undefined x = undefined".
  3802 
  3803 * Added class "HOL.eq", allowing for code generation with polymorphic
  3804 equality.
  3805 
  3806 * Some renaming of class constants due to canonical name prefixing in
  3807 the new 'class' package:
  3808 
  3809     HOL.abs ~> HOL.abs_class.abs
  3810     HOL.divide ~> HOL.divide_class.divide
  3811     0 ~> HOL.zero_class.zero
  3812     1 ~> HOL.one_class.one
  3813     op + ~> HOL.plus_class.plus
  3814     op - ~> HOL.minus_class.minus
  3815     uminus ~> HOL.minus_class.uminus
  3816     op * ~> HOL.times_class.times
  3817     op < ~> HOL.ord_class.less
  3818     op <= > HOL.ord_class.less_eq
  3819     Nat.power ~> Power.power_class.power
  3820     Nat.size ~> Nat.size_class.size
  3821     Numeral.number_of ~> Numeral.number_class.number_of
  3822     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3823     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3824     Orderings.min ~> Orderings.ord_class.min
  3825     Orderings.max ~> Orderings.ord_class.max
  3826     Divides.op div ~> Divides.div_class.div
  3827     Divides.op mod ~> Divides.div_class.mod
  3828     Divides.op dvd ~> Divides.div_class.dvd
  3829 
  3830 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3831 
  3832 a) User-defined constants using any of the names "plus", "minus",
  3833 "times", "less" or "less_eq". The standard syntax translations for
  3834 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3835 names.
  3836 
  3837 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3838 INCOMPATIBILITY: use more specific names.
  3839 
  3840 c) Permutative equations (e.g. "a + b = b + a")
  3841 Since the change of names also changes the order of terms, permutative
  3842 rewrite rules may get applied in a different order. Experience shows
  3843 that this is rarely the case (only two adaptions in the whole Isabelle
  3844 distribution).  INCOMPATIBILITY: rewrite proofs
  3845 
  3846 d) ML code directly refering to constant names
  3847 This in general only affects hand-written proof tactics, simprocs and
  3848 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3849 Consider using @{const_name} antiquotation.
  3850 
  3851 * New class "default" with associated constant "default".
  3852 
  3853 * Function "sgn" is now overloaded and available on int, real, complex
  3854 (and other numeric types), using class "sgn".  Two possible defs of
  3855 sgn are given as equational assumptions in the classes sgn_if and
  3856 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3857 INCOMPATIBILITY.
  3858 
  3859 * Locale "partial_order" now unified with class "order" (cf. theory
  3860 Orderings), added parameter "less".  INCOMPATIBILITY.
  3861 
  3862 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3863 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3864 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3865 
  3866 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3867 changed order of proof goals in instance proofs.
  3868 
  3869 * The transitivity reasoner for partial and linear orders is set up
  3870 for classes "order" and "linorder".  Instances of the reasoner are available
  3871 in all contexts importing or interpreting the corresponding locales.
  3872 Method "order" invokes the reasoner separately; the reasoner
  3873 is also integrated with the Simplifier as a solver.  Diagnostic
  3874 command 'print_orders' shows the available instances of the reasoner
  3875 in the current context.
  3876 
  3877 * Localized monotonicity predicate in theory "Orderings"; integrated
  3878 lemmas max_of_mono and min_of_mono with this predicate.
  3879 INCOMPATIBILITY.
  3880 
  3881 * Formulation of theorem "dense" changed slightly due to integration
  3882 with new class dense_linear_order.
  3883 
  3884 * Uniform lattice theory development in HOL.
  3885 
  3886     constants "meet" and "join" now named "inf" and "sup"
  3887     constant "Meet" now named "Inf"
  3888 
  3889     classes "meet_semilorder" and "join_semilorder" now named
  3890       "lower_semilattice" and "upper_semilattice"
  3891     class "lorder" now named "lattice"
  3892     class "comp_lat" now named "complete_lattice"
  3893 
  3894     Instantiation of lattice classes allows explicit definitions
  3895     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3896 
  3897   INCOMPATIBILITY.  Theorem renames:
  3898 
  3899     meet_left_le            ~> inf_le1
  3900     meet_right_le           ~> inf_le2
  3901     join_left_le            ~> sup_ge1
  3902     join_right_le           ~> sup_ge2
  3903     meet_join_le            ~> inf_sup_ord
  3904     le_meetI                ~> le_infI
  3905     join_leI                ~> le_supI
  3906     le_meet                 ~> le_inf_iff
  3907     le_join                 ~> ge_sup_conv
  3908     meet_idempotent         ~> inf_idem
  3909     join_idempotent         ~> sup_idem
  3910     meet_comm               ~> inf_commute
  3911     join_comm               ~> sup_commute
  3912     meet_leI1               ~> le_infI1
  3913     meet_leI2               ~> le_infI2
  3914     le_joinI1               ~> le_supI1
  3915     le_joinI2               ~> le_supI2
  3916     meet_assoc              ~> inf_assoc
  3917     join_assoc              ~> sup_assoc
  3918     meet_left_comm          ~> inf_left_commute
  3919     meet_left_idempotent    ~> inf_left_idem
  3920     join_left_comm          ~> sup_left_commute
  3921     join_left_idempotent    ~> sup_left_idem
  3922     meet_aci                ~> inf_aci
  3923     join_aci                ~> sup_aci
  3924     le_def_meet             ~> le_iff_inf
  3925     le_def_join             ~> le_iff_sup
  3926     join_absorp2            ~> sup_absorb2
  3927     join_absorp1            ~> sup_absorb1
  3928     meet_absorp1            ~> inf_absorb1
  3929     meet_absorp2            ~> inf_absorb2
  3930     meet_join_absorp        ~> inf_sup_absorb
  3931     join_meet_absorp        ~> sup_inf_absorb
  3932     distrib_join_le         ~> distrib_sup_le
  3933     distrib_meet_le         ~> distrib_inf_le
  3934 
  3935     add_meet_distrib_left   ~> add_inf_distrib_left
  3936     add_join_distrib_left   ~> add_sup_distrib_left
  3937     is_join_neg_meet        ~> is_join_neg_inf
  3938     is_meet_neg_join        ~> is_meet_neg_sup
  3939     add_meet_distrib_right  ~> add_inf_distrib_right
  3940     add_join_distrib_right  ~> add_sup_distrib_right
  3941     add_meet_join_distribs  ~> add_sup_inf_distribs
  3942     join_eq_neg_meet        ~> sup_eq_neg_inf
  3943     meet_eq_neg_join        ~> inf_eq_neg_sup
  3944     add_eq_meet_join        ~> add_eq_inf_sup
  3945     meet_0_imp_0            ~> inf_0_imp_0
  3946     join_0_imp_0            ~> sup_0_imp_0
  3947     meet_0_eq_0             ~> inf_0_eq_0
  3948     join_0_eq_0             ~> sup_0_eq_0
  3949     neg_meet_eq_join        ~> neg_inf_eq_sup
  3950     neg_join_eq_meet        ~> neg_sup_eq_inf
  3951     join_eq_if              ~> sup_eq_if
  3952 
  3953     mono_meet               ~> mono_inf
  3954     mono_join               ~> mono_sup
  3955     meet_bool_eq            ~> inf_bool_eq
  3956     join_bool_eq            ~> sup_bool_eq
  3957     meet_fun_eq             ~> inf_fun_eq
  3958     join_fun_eq             ~> sup_fun_eq
  3959     meet_set_eq             ~> inf_set_eq
  3960     join_set_eq             ~> sup_set_eq
  3961     meet1_iff               ~> inf1_iff
  3962     meet2_iff               ~> inf2_iff
  3963     meet1I                  ~> inf1I
  3964     meet2I                  ~> inf2I
  3965     meet1D1                 ~> inf1D1
  3966     meet2D1                 ~> inf2D1
  3967     meet1D2                 ~> inf1D2
  3968     meet2D2                 ~> inf2D2
  3969     meet1E                  ~> inf1E
  3970     meet2E                  ~> inf2E
  3971     join1_iff               ~> sup1_iff
  3972     join2_iff               ~> sup2_iff
  3973     join1I1                 ~> sup1I1
  3974     join2I1                 ~> sup2I1
  3975     join1I1                 ~> sup1I1
  3976     join2I2                 ~> sup1I2
  3977     join1CI                 ~> sup1CI
  3978     join2CI                 ~> sup2CI
  3979     join1E                  ~> sup1E
  3980     join2E                  ~> sup2E
  3981 
  3982     is_meet_Meet            ~> is_meet_Inf
  3983     Meet_bool_def           ~> Inf_bool_def
  3984     Meet_fun_def            ~> Inf_fun_def
  3985     Meet_greatest           ~> Inf_greatest
  3986     Meet_lower              ~> Inf_lower
  3987     Meet_set_def            ~> Inf_set_def
  3988 
  3989     Sup_def                 ~> Sup_Inf
  3990     Sup_bool_eq             ~> Sup_bool_def
  3991     Sup_fun_eq              ~> Sup_fun_def
  3992     Sup_set_eq              ~> Sup_set_def
  3993 
  3994     listsp_meetI            ~> listsp_infI
  3995     listsp_meet_eq          ~> listsp_inf_eq
  3996 
  3997     meet_min                ~> inf_min
  3998     join_max                ~> sup_max
  3999 
  4000 * Added syntactic class "size"; overloaded constant "size" now has
  4001 type "'a::size ==> bool"
  4002 
  4003 * Internal reorganisation of `size' of datatypes: size theorems
  4004 "foo.size" are no longer subsumed by "foo.simps" (but are still
  4005 simplification rules by default!); theorems "prod.size" now named
  4006 "*.size".
  4007 
  4008 * Class "div" now inherits from class "times" rather than "type".
  4009 INCOMPATIBILITY.
  4010 
  4011 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  4012 Linorder etc.  have disappeared; operations defined in terms of
  4013 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  4014 
  4015 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  4016 
  4017 * HOL-Word: New extensive library and type for generic, fixed size
  4018 machine words, with arithemtic, bit-wise, shifting and rotating
  4019 operations, reflection into int, nat, and bool lists, automation for
  4020 linear arithmetic (by automatic reflection into nat or int), including
  4021 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  4022 arithmetic type classes, supporting automatic simplification of
  4023 numerals on all operations.
  4024 
  4025 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  4026 
  4027 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  4028 
  4029 * Code generator library theories:
  4030   - Code_Integer represents HOL integers by big integer literals in target
  4031     languages.
  4032   - Code_Char represents HOL characters by character literals in target
  4033     languages.
  4034   - Code_Char_chr like Code_Char, but also offers treatment of character
  4035     codes; includes Code_Integer.
  4036   - Executable_Set allows to generate code for finite sets using lists.
  4037   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  4038     denominator).
  4039   - Executable_Real implements a subset of real numbers, namly those
  4040     representable by rational numbers.
  4041   - Efficient_Nat implements natural numbers by integers, which in general will
  4042     result in higher efficency; pattern matching with 0/Suc is eliminated;
  4043     includes Code_Integer.
  4044   - Code_Index provides an additional datatype index which is mapped to
  4045     target-language built-in integers.
  4046   - Code_Message provides an additional datatype message_string which is isomorphic to
  4047     strings; messages are mapped to target-language strings.
  4048 
  4049 * New package for inductive predicates
  4050 
  4051   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  4052 
  4053     inductive
  4054       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4055       for z_1 :: U_1 and ... and z_n :: U_m
  4056     where
  4057       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4058     | ...
  4059 
  4060   with full support for type-inference, rather than
  4061 
  4062     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4063 
  4064     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4065     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4066 
  4067     inductive "s z_1 ... z_m"
  4068     intros
  4069       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4070       ...
  4071 
  4072   For backward compatibility, there is a wrapper allowing inductive
  4073   sets to be defined with the new package via
  4074 
  4075     inductive_set
  4076       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4077       for z_1 :: U_1 and ... and z_n :: U_m
  4078     where
  4079       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4080     | ...
  4081 
  4082   or
  4083 
  4084     inductive_set
  4085       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4086       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4087       for z_1 :: U_1 and ... and z_n :: U_m
  4088     where
  4089       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4090     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4091     | ...
  4092 
  4093   if the additional syntax "p ..." is required.
  4094 
  4095   Numerous examples can be found in the subdirectories src/HOL/Auth,
  4096   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  4097 
  4098   INCOMPATIBILITIES:
  4099 
  4100   - Since declaration and definition of inductive sets or predicates
  4101     is no longer separated, abbreviations involving the newly
  4102     introduced sets or predicates must be specified together with the
  4103     introduction rules after the 'where' keyword (see above), rather
  4104     than before the actual inductive definition.
  4105 
  4106   - The variables in induction and elimination rules are now
  4107     quantified in the order of their occurrence in the introduction
  4108     rules, rather than in alphabetical order. Since this may break
  4109     some proofs, these proofs either have to be repaired, e.g. by
  4110     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  4111     statements of the form
  4112 
  4113       case (rule_i a_i_1 ... a_i_{k_i})
  4114 
  4115     or the old order of quantification has to be restored by explicitly adding
  4116     meta-level quantifiers in the introduction rules, i.e.
  4117 
  4118       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  4119 
  4120   - The format of the elimination rules is now
  4121 
  4122       p z_1 ... z_m x_1 ... x_n ==>
  4123         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4124         ==> ... ==> P
  4125 
  4126     for predicates and
  4127 
  4128       (x_1, ..., x_n) : s z_1 ... z_m ==>
  4129         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4130         ==> ... ==> P
  4131 
  4132     for sets rather than
  4133 
  4134       x : s z_1 ... z_m ==>
  4135         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  4136         ==> ... ==> P
  4137 
  4138     This may require terms in goals to be expanded to n-tuples
  4139     (e.g. using case_tac or simplification with the split_paired_all
  4140     rule) before the above elimination rule is applicable.
  4141 
  4142   - The elimination or case analysis rules for (mutually) inductive
  4143     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  4144     list of rules "p_1_..._p_k.elims" is no longer available.
  4145 
  4146 * New package "function"/"fun" for general recursive functions,
  4147 supporting mutual and nested recursion, definitions in local contexts,
  4148 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  4149 for small examples, and the separate tutorial on the function
  4150 package. The old recdef "package" is still available as before, but
  4151 users are encouraged to use the new package.
  4152 
  4153 * Method "lexicographic_order" automatically synthesizes termination
  4154 relations as lexicographic combinations of size measures. 
  4155 
  4156 * Case-expressions allow arbitrary constructor-patterns (including
  4157 "_") and take their order into account, like in functional
  4158 programming.  Internally, this is translated into nested
  4159 case-expressions; missing cases are added and mapped to the predefined
  4160 constant "undefined". In complicated cases printing may no longer show
  4161 the original input but the internal form. Lambda-abstractions allow
  4162 the same form of pattern matching: "% pat1 => e1 | ..." is an
  4163 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  4164 variable.
  4165 
  4166 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  4167 is an abbreviation for "of_nat :: nat => int". The simplification
  4168 rules for "of_nat" have been changed to work like "int" did
  4169 previously.  Potential INCOMPATIBILITY:
  4170   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  4171   - of_nat_diff and of_nat_mult are no longer default simp rules
  4172 
  4173 * Method "algebra" solves polynomial equations over (semi)rings using
  4174 Groebner bases. The (semi)ring structure is defined by locales and the
  4175 tool setup depends on that generic context. Installing the method for
  4176 a specific type involves instantiating the locale and possibly adding
  4177 declarations for computation on the coefficients.  The method is
  4178 already instantiated for natural numbers and for the axiomatic class
  4179 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  4180 CALCULEMUS 2007 for the general principles underlying this
  4181 architecture of context-aware proof-tools.
  4182 
  4183 * Method "ferrack" implements quantifier elimination over
  4184 special-purpose dense linear orders using locales (analogous to
  4185 "algebra"). The method is already installed for class
  4186 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  4187 rat, etc.
  4188 
  4189 * Former constant "List.op @" now named "List.append".  Use ML
  4190 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  4191 circumvent possible incompatibilities when working on ML level.
  4192 
  4193 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  4194 
  4195 * New function listsum :: 'a list => 'a for arbitrary monoids.
  4196 Special syntax: "SUM x <- xs. f x" (and latex variants)
  4197 
  4198 * New syntax for Haskell-like list comprehension (input only), eg.
  4199 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  4200 
  4201 * The special syntax for function "filter" has changed from [x :
  4202 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  4203 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  4204 
  4205 * [a..b] is now defined for arbitrary linear orders.  It used to be
  4206 defined on nat only, as an abbreviation for [a..<Suc b]
  4207 INCOMPATIBILITY.
  4208 
  4209 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  4210 
  4211 * New functions "sorted" and "sort" in src/HOL/List.thy.
  4212 
  4213 * New lemma collection field_simps (an extension of ring_simps) for
  4214 manipulating (in)equations involving division. Multiplies with all
  4215 denominators that can be proved to be non-zero (in equations) or
  4216 positive/negative (in inequations).
  4217 
  4218 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  4219 have been improved and renamed to ring_simps, group_simps and
  4220 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  4221 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  4222 
  4223 * Theory Library/Commutative_Ring: switched from recdef to function
  4224 package; constants add, mul, pow now curried.  Infix syntax for
  4225 algebraic operations.
  4226 
  4227 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  4228 INCOMPATIBILITY.
  4229 
  4230 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  4231 INCOMPATIBILITY.
  4232 
  4233 * HOL/records: generalised field-update to take a function on the
  4234 field rather than the new value: r(|A := x|) is translated to A_update
  4235 (K x) r The K-combinator that is internally used is called K_record.
  4236 INCOMPATIBILITY: Usage of the plain update functions has to be
  4237 adapted.
  4238  
  4239 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  4240 * x = 0, which are required for a semiring.  Richer structures do not
  4241 inherit from semiring_0 anymore, because this property is a theorem
  4242 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  4243 there is more to prove, but this is mostly trivial.
  4244 
  4245 * Class "recpower" is generalized to arbitrary monoids, not just
  4246 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  4247 commutativity or semiring properties additionally.
  4248 
  4249 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  4250 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  4251 better use 'abbreviation'.
  4252 
  4253 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  4254 
  4255 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  4256 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  4257 significant changes for setting up numeral syntax for types:
  4258   - New constants Numeral.pred and Numeral.succ instead
  4259       of former Numeral.bin_pred and Numeral.bin_succ.
  4260   - Use integer operations instead of bin_add, bin_mult and so on.
  4261   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  4262   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  4263 
  4264 See src/HOL/Integ/IntArith.thy for an example setup.
  4265 
  4266 * Command 'normal_form' computes the normal form of a term that may
  4267 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  4268 produces ``[b, c, a]'' (without proof).  This command is suitable for
  4269 heavy-duty computations because the functions are compiled to ML
  4270 first.  Correspondingly, a method "normalization" is provided.  See
  4271 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  4272 
  4273 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  4274 25 like -->); output depends on the "iff" print_mode, the default is
  4275 "A = B" (with priority 50).
  4276 
  4277 * Relations less (<) and less_eq (<=) are also available on type bool.
  4278 Modified syntax to disallow nesting without explicit parentheses,
  4279 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  4280 INCOMPATIBILITY.
  4281 
  4282 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  4283 
  4284 * Relation composition operator "op O" now has precedence 75 and binds
  4285 stronger than union and intersection. INCOMPATIBILITY.
  4286 
  4287 * The old set interval syntax "{m..n(}" (and relatives) has been
  4288 removed.  Use "{m..<n}" (and relatives) instead.
  4289 
  4290 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  4291 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  4292 ``declare [[simproc del: neq]]''.
  4293 
  4294 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  4295 True/False.
  4296 
  4297 * Theorem Cons_eq_map_conv no longer declared as "simp".
  4298 
  4299 * Theorem setsum_mult renamed to setsum_right_distrib.
  4300 
  4301 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  4302 ``rule'' method.
  4303 
  4304 * Reimplemented methods "sat" and "satx", with several improvements:
  4305 goals no longer need to be stated as "<prems> ==> False", equivalences
  4306 (i.e. "=" on type bool) are handled, variable names of the form
  4307 "lit_<n>" are no longer reserved, significant speedup.
  4308 
  4309 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  4310 zChaff is still supported as well.
  4311 
  4312 * 'inductive' and 'datatype': provide projections of mutual rules,
  4313 bundled as foo_bar.inducts;
  4314 
  4315 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  4316 Library.
  4317 
  4318 * Library: moved theory Accessible_Part to main HOL.
  4319 
  4320 * Library: added theory Coinductive_List of potentially infinite lists
  4321 as greatest fixed-point.
  4322 
  4323 * Library: added theory AssocList which implements (finite) maps as
  4324 association lists.
  4325 
  4326 * Method "evaluation" solves goals (i.e. a boolean expression)
  4327 efficiently by compiling it to ML.  The goal is "proved" (via an
  4328 oracle) if it evaluates to True.
  4329 
  4330 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  4331 also when invoked by the simplifier.  This results in the Simplifier
  4332 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  4333 Configuration option fast_arith_split_limit=0 recovers the old
  4334 behavior.
  4335 
  4336 * Support for hex (0x20) and binary (0b1001) numerals.
  4337 
  4338 * New method: reify eqs (t), where eqs are equations for an
  4339 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  4340 parameter, computes a term s::'b and a list xs::'a list and proves the
  4341 theorem I xs s = t. This is also known as reification or quoting. The
  4342 resulting theorem is applied to the subgoal to substitute t with I xs
  4343 s.  If t is omitted, the subgoal itself is reified.
  4344 
  4345 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  4346 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  4347 where f is supposed to be a computable function (in the sense of code
  4348 generattion). The method uses reify to compute s and xs as above then
  4349 applies corr_thm and uses normalization by evaluation to "prove" f s =
  4350 r and finally gets the theorem t = r, which is again applied to the
  4351 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  4352 
  4353 * Reflection: Automatic reification now handels binding, an example is
  4354 available in src/HOL/ex/ReflectionEx.thy
  4355 
  4356 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  4357 command 'statespace' that is similar to 'record', but introduces an
  4358 abstract specification based on the locale infrastructure instead of
  4359 HOL types.  This leads to extra flexibility in composing state spaces,
  4360 in particular multiple inheritance and renaming of components.
  4361 
  4362 
  4363 *** HOL-Complex ***
  4364 
  4365 * Hyperreal: Functions root and sqrt are now defined on negative real
  4366 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  4367 Nonnegativity side conditions have been removed from many lemmas, so
  4368 that more subgoals may now be solved by simplification; potential
  4369 INCOMPATIBILITY.
  4370 
  4371 * Real: new type classes formalize real normed vector spaces and
  4372 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  4373 and norm :: 'a => real.
  4374 
  4375 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  4376 reals into other types. The overloaded constant Reals :: 'a set is now
  4377 defined as range of_real; potential INCOMPATIBILITY.
  4378 
  4379 * Real: proper support for ML code generation, including 'quickcheck'.
  4380 Reals are implemented as arbitrary precision rationals.
  4381 
  4382 * Hyperreal: Several constants that previously worked only for the
  4383 reals have been generalized, so they now work over arbitrary vector
  4384 spaces. Type annotations may need to be added in some cases; potential
  4385 INCOMPATIBILITY.
  4386 
  4387   Infinitesimal  :: ('a::real_normed_vector) star set
  4388   HFinite        :: ('a::real_normed_vector) star set
  4389   HInfinite      :: ('a::real_normed_vector) star set
  4390   approx         :: ('a::real_normed_vector) star => 'a star => bool
  4391   monad          :: ('a::real_normed_vector) star => 'a star set
  4392   galaxy         :: ('a::real_normed_vector) star => 'a star set
  4393   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  4394   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  4395   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  4396   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  4397   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  4398   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  4399   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  4400   sgn            :: 'a::real_normed_vector => 'a
  4401   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  4402 
  4403 * Complex: Some complex-specific constants are now abbreviations for
  4404 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  4405 hnorm.  Other constants have been entirely removed in favor of the
  4406 polymorphic versions (INCOMPATIBILITY):
  4407 
  4408   approx        <-- capprox
  4409   HFinite       <-- CFinite
  4410   HInfinite     <-- CInfinite
  4411   Infinitesimal <-- CInfinitesimal
  4412   monad         <-- cmonad
  4413   galaxy        <-- cgalaxy
  4414   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  4415   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  4416   (ns)deriv     <-- (ns)cderiv
  4417 
  4418 
  4419 *** HOL-Algebra ***
  4420 
  4421 * Formalisation of ideals and the quotient construction over rings.
  4422 
  4423 * Order and lattice theory no longer based on records.
  4424 INCOMPATIBILITY.
  4425 
  4426 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  4427 greatest_closed.  INCOMPATIBILITY.
  4428 
  4429 * Method algebra is now set up via an attribute.  For examples see
  4430 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  4431 of algebraic structures.
  4432 
  4433 * Renamed theory CRing to Ring.
  4434 
  4435 
  4436 *** HOL-Nominal ***
  4437 
  4438 * Substantial, yet incomplete support for nominal datatypes (binding
  4439 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  4440 src/HOL/Nominal/Examples.  Prospective users should consult
  4441 http://isabelle.in.tum.de/nominal/
  4442 
  4443 
  4444 *** ML ***
  4445 
  4446 * ML basics: just one true type int, which coincides with IntInf.int
  4447 (even on SML/NJ).
  4448 
  4449 * ML within Isar: antiquotations allow to embed statically-checked
  4450 formal entities in the source, referring to the context available at
  4451 compile-time.  For example:
  4452 
  4453 ML {* @{sort "{zero,one}"} *}
  4454 ML {* @{typ "'a => 'b"} *}
  4455 ML {* @{term "%x. x"} *}
  4456 ML {* @{prop "x == y"} *}
  4457 ML {* @{ctyp "'a => 'b"} *}
  4458 ML {* @{cterm "%x. x"} *}
  4459 ML {* @{cprop "x == y"} *}
  4460 ML {* @{thm asm_rl} *}
  4461 ML {* @{thms asm_rl} *}
  4462 ML {* @{type_name c} *}
  4463 ML {* @{type_syntax c} *}
  4464 ML {* @{const_name c} *}
  4465 ML {* @{const_syntax c} *}
  4466 ML {* @{context} *}
  4467 ML {* @{theory} *}
  4468 ML {* @{theory Pure} *}
  4469 ML {* @{theory_ref} *}
  4470 ML {* @{theory_ref Pure} *}
  4471 ML {* @{simpset} *}
  4472 ML {* @{claset} *}
  4473 ML {* @{clasimpset} *}
  4474 
  4475 The same works for sources being ``used'' within an Isar context.
  4476 
  4477 * ML in Isar: improved error reporting; extra verbosity with
  4478 ML_Context.trace enabled.
  4479 
  4480 * Pure/General/table.ML: the join operations now works via exceptions
  4481 DUP/SAME instead of type option. This is simpler in simple cases, and
  4482 admits slightly more efficient complex applications.
  4483 
  4484 * Pure: 'advanced' translation functions (parse_translation etc.) now
  4485 use Context.generic instead of just theory.
  4486 
  4487 * Pure: datatype Context.generic joins theory/Proof.context and
  4488 provides some facilities for code that works in either kind of
  4489 context, notably GenericDataFun for uniform theory and proof data.
  4490 
  4491 * Pure: simplified internal attribute type, which is now always
  4492 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  4493 local (Proof.context) attributes have been discontinued, while
  4494 minimizing code duplication. Thm.rule_attribute and
  4495 Thm.declaration_attribute build canonical attributes; see also structure
  4496 Context for further operations on Context.generic, notably
  4497 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  4498 declarations and definitions.
  4499 
  4500 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  4501 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  4502 init only required for impure data. INCOMPATIBILITY: empty really need
  4503 to be empty (no dependencies on theory content!)
  4504 
  4505 * Pure/kernel: consts certification ignores sort constraints given in
  4506 signature declarations. (This information is not relevant to the
  4507 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  4508 potential INCOMPATIBILITY.
  4509 
  4510 * Pure: axiomatic type classes are now purely definitional, with
  4511 explicit proofs of class axioms and super class relations performed
  4512 internally. See Pure/axclass.ML for the main internal interfaces --
  4513 notably AxClass.define_class supercedes AxClass.add_axclass, and
  4514 AxClass.axiomatize_class/classrel/arity supersede
  4515 Sign.add_classes/classrel/arities.
  4516 
  4517 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  4518 global/local versions on theory vs. Proof.context have been
  4519 discontinued; Attrib.syntax and Method.syntax have been adapted
  4520 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  4521 attributes, methods, etc.
  4522 
  4523 * Pure: several functions of signature "... -> theory -> theory * ..."
  4524 have been reoriented to "... -> theory -> ... * theory" in order to
  4525 allow natural usage in combination with the ||>, ||>>, |-> and
  4526 fold_map combinators.
  4527 
  4528 * Pure: official theorem names (closed derivations) and additional
  4529 comments (tags) are now strictly separate.  Name hints -- which are
  4530 maintained as tags -- may be attached any time without affecting the
  4531 derivation.
  4532 
  4533 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  4534 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  4535 achieve the old behaviour.
  4536 
  4537 * Pure: the "Goal" constant is now called "prop", supporting a
  4538 slightly more general idea of ``protecting'' meta-level rule
  4539 statements.
  4540 
  4541 * Pure: Logic.(un)varify only works in a global context, which is now
  4542 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  4543 Logic.legacy_(un)varify as temporary workaround.
  4544 
  4545 * Pure: structure Name provides scalable operations for generating
  4546 internal variable names, notably Name.variants etc.  This replaces
  4547 some popular functions from term.ML:
  4548 
  4549   Term.variant		->  Name.variant
  4550   Term.variantlist	->  Name.variant_list
  4551   Term.invent_names	->  Name.invent_list
  4552 
  4553 Note that low-level renaming rarely occurs in new code -- operations
  4554 from structure Variable are used instead (see below).
  4555 
  4556 * Pure: structure Variable provides fundamental operations for proper
  4557 treatment of fixed/schematic variables in a context.  For example,
  4558 Variable.import introduces fixes for schematics of given facts and
  4559 Variable.export reverses the effect (up to renaming) -- this replaces
  4560 various freeze_thaw operations.
  4561 
  4562 * Pure: structure Goal provides simple interfaces for
  4563 init/conclude/finish and tactical prove operations (replacing former
  4564 Tactic.prove).  Goal.prove is the canonical way to prove results
  4565 within a given context; Goal.prove_global is a degraded version for
  4566 theory level goals, including a global Drule.standard.  Note that
  4567 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  4568 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  4569 in a locale context).
  4570 
  4571 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  4572 and type checking (Syntax.check_term etc.), with common combinations
  4573 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  4574 which are considered legacy and await removal.
  4575 
  4576 * Pure/Syntax: generic interfaces for type unchecking
  4577 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  4578 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  4579 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  4580 available for convenience, but refer to the very same operations using
  4581 a mere theory instead of a full context.
  4582 
  4583 * Isar: simplified treatment of user-level errors, using exception
  4584 ERROR of string uniformly.  Function error now merely raises ERROR,
  4585 without any side effect on output channels.  The Isar toplevel takes
  4586 care of proper display of ERROR exceptions.  ML code may use plain
  4587 handle/can/try; cat_error may be used to concatenate errors like this:
  4588 
  4589   ... handle ERROR msg => cat_error msg "..."
  4590 
  4591 Toplevel ML code (run directly or through the Isar toplevel) may be
  4592 embedded into the Isar toplevel with exception display/debug like
  4593 this:
  4594 
  4595   Isar.toplevel (fn () => ...)
  4596 
  4597 INCOMPATIBILITY, removed special transform_error facilities, removed
  4598 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  4599 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  4600 -- use plain ERROR instead.
  4601 
  4602 * Isar: theory setup now has type (theory -> theory), instead of a
  4603 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  4604 
  4605 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  4606 ProofContext.debug/verbose flags.
  4607 
  4608 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  4609 theory before entering a proof state.  Transactions now always see a
  4610 quasi-functional intermediate checkpoint, both in interactive and
  4611 batch mode.
  4612 
  4613 * Isar: simplified interfaces for outer syntax.  Renamed
  4614 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  4615 OuterSyntax.add_parsers -- this functionality is now included in
  4616 OuterSyntax.command etc.  INCOMPATIBILITY.
  4617 
  4618 * Simplifier: the simpset of a running simplification process now
  4619 contains a proof context (cf. Simplifier.the_context), which is the
  4620 very context that the initial simpset has been retrieved from (by
  4621 simpset_of/local_simpset_of).  Consequently, all plug-in components
  4622 (solver, looper etc.) may depend on arbitrary proof data.
  4623 
  4624 * Simplifier.inherit_context inherits the proof context (plus the
  4625 local bounds) of the current simplification process; any simproc
  4626 etc. that calls the Simplifier recursively should do this!  Removed
  4627 former Simplifier.inherit_bounds, which is already included here --
  4628 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  4629 specify an explicit context using Simplifier.context/theory_context.
  4630 
  4631 * Simplifier/Classical Reasoner: more abstract interfaces
  4632 change_simpset/claset for modifying the simpset/claset reference of a
  4633 theory; raw versions simpset/claset_ref etc. have been discontinued --
  4634 INCOMPATIBILITY.
  4635 
  4636 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  4637 "Trueprop" etc.
  4638 
  4639 
  4640 *** System ***
  4641 
  4642 * settings: the default heap location within ISABELLE_HOME_USER now
  4643 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  4644 Isabelle installations.
  4645 
  4646 * isabelle-process: option -S (secure mode) disables some critical
  4647 operations, notably runtime compilation and evaluation of ML source
  4648 code.
  4649 
  4650 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  4651 
  4652 * Support for parallel execution, using native multicore support of
  4653 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  4654 independent theories, according to the given theory header
  4655 specifications. The maximum number of worker threads is specified via
  4656 usedir option -M or the "max-threads" setting in Proof General. A
  4657 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  4658 to 6 on a 8-core machine.  User-code needs to observe certain
  4659 guidelines for thread-safe programming, see appendix A in the Isar
  4660 Implementation manual.
  4661 
  4662 
  4663 
  4664 New in Isabelle2005 (October 2005)
  4665 ----------------------------------
  4666 
  4667 *** General ***
  4668 
  4669 * Theory headers: the new header syntax for Isar theories is
  4670 
  4671   theory <name>
  4672   imports <theory1> ... <theoryN>
  4673   uses <file1> ... <fileM>
  4674   begin
  4675 
  4676 where the 'uses' part is optional.  The previous syntax
  4677 
  4678   theory <name> = <theory1> + ... + <theoryN>:
  4679 
  4680 will disappear in the next release.  Use isatool fixheaders to convert
  4681 existing theory files.  Note that there is no change in ancient
  4682 non-Isar theories now, but these will disappear soon.
  4683 
  4684 * Theory loader: parent theories can now also be referred to via
  4685 relative and absolute paths.
  4686 
  4687 * Command 'find_theorems' searches for a list of criteria instead of a
  4688 list of constants. Known criteria are: intro, elim, dest, name:string,
  4689 simp:term, and any term. Criteria can be preceded by '-' to select
  4690 theorems that do not match. Intro, elim, dest select theorems that
  4691 match the current goal, name:s selects theorems whose fully qualified
  4692 name contain s, and simp:term selects all simplification rules whose
  4693 lhs match term.  Any other term is interpreted as pattern and selects
  4694 all theorems matching the pattern. Available in ProofGeneral under
  4695 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  4696 
  4697   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  4698 
  4699 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  4700 matching the current goal as introduction rule and not having "HOL."
  4701 in their name (i.e. not being defined in theory HOL).
  4702 
  4703 * Command 'thms_containing' has been discontinued in favour of
  4704 'find_theorems'; INCOMPATIBILITY.
  4705 
  4706 * Communication with Proof General is now 8bit clean, which means that
  4707 Unicode text in UTF-8 encoding may be used within theory texts (both
  4708 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4709 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4710 
  4711   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4712   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4713 
  4714 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4715 Classical Reasoner.  Typical big applications run around 2 times
  4716 faster.
  4717 
  4718 
  4719 *** Document preparation ***
  4720 
  4721 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4722 of raw sources.  Only those symbols that do not require additional
  4723 LaTeX packages (depending on comments in isabellesym.sty) are
  4724 displayed properly, everything else is left verbatim.  isatool display
  4725 and isatool print are used as front ends (these are subject to the
  4726 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4727 
  4728 * Command tags control specific markup of certain regions of text,
  4729 notably folding and hiding.  Predefined tags include "theory" (for
  4730 theory begin and end), "proof" for proof commands, and "ML" for
  4731 commands involving ML code; the additional tags "visible" and
  4732 "invisible" are unused by default.  Users may give explicit tag
  4733 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4734 interpretation of tags is determined by the LaTeX job during document
  4735 preparation: see option -V of isatool usedir, or options -n and -t of
  4736 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4737 \isadroptag.
  4738 
  4739 Several document versions may be produced at the same time via isatool
  4740 usedir (the generated index.html will link all of them).  Typical
  4741 specifications include ''-V document=theory,proof,ML'' to present
  4742 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4743 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4744 these parts without any formal replacement text.  The Isabelle site
  4745 default settings produce ''document'' and ''outline'' versions as
  4746 specified above.
  4747 
  4748 * Several new antiquotations:
  4749 
  4750   @{term_type term} prints a term with its type annotated;
  4751 
  4752   @{typeof term} prints the type of a term;
  4753 
  4754   @{const const} is the same as @{term const}, but checks that the
  4755   argument is a known logical constant;
  4756 
  4757   @{term_style style term} and @{thm_style style thm} print a term or
  4758   theorem applying a "style" to it
  4759 
  4760   @{ML text}
  4761 
  4762 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4763 definitions, equations, inequations etc., 'concl' printing only the
  4764 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4765 to print the specified premise.  TermStyle.add_style provides an ML
  4766 interface for introducing further styles.  See also the "LaTeX Sugar"
  4767 document practical applications.  The ML antiquotation prints
  4768 type-checked ML expressions verbatim.
  4769 
  4770 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4771 and 'text' support optional locale specification '(in loc)', which
  4772 specifies the default context for interpreting antiquotations.  For
  4773 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4774 
  4775 * Option 'locale=NAME' of antiquotations specifies an alternative
  4776 context interpreting the subsequent argument.  For example: @{thm
  4777 [locale=lattice] inf_assoc}.
  4778 
  4779 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4780 a proof context.
  4781 
  4782 * Proper output of antiquotations for theory commands involving a
  4783 proof context (such as 'locale' or 'theorem (in loc) ...').
  4784 
  4785 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4786 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4787 
  4788 * isatool usedir: new option -C (default true) controls whether option
  4789 -D should include a copy of the original document directory; -C false
  4790 prevents unwanted effects such as copying of administrative CVS data.
  4791 
  4792 
  4793 *** Pure ***
  4794 
  4795 * Considerably improved version of 'constdefs' command.  Now performs
  4796 automatic type-inference of declared constants; additional support for
  4797 local structure declarations (cf. locales and HOL records), see also
  4798 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4799 sequential dependencies of definitions within a single 'constdefs'
  4800 section; moreover, the declared name needs to be an identifier.  If
  4801 all fails, consider to fall back on 'consts' and 'defs' separately.
  4802 
  4803 * Improved indexed syntax and implicit structures.  First of all,
  4804 indexed syntax provides a notational device for subscripted
  4805 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4806 expressions.  Secondly, in a local context with structure
  4807 declarations, number indexes \<^sub>n or the empty index (default
  4808 number 1) refer to a certain fixed variable implicitly; option
  4809 show_structs controls printing of implicit structures.  Typical
  4810 applications of these concepts involve record types and locales.
  4811 
  4812 * New command 'no_syntax' removes grammar declarations (and
  4813 translations) resulting from the given syntax specification, which is
  4814 interpreted in the same manner as for the 'syntax' command.
  4815 
  4816 * 'Advanced' translation functions (parse_translation etc.) may depend
  4817 on the signature of the theory context being presently used for
  4818 parsing/printing, see also isar-ref manual.
  4819 
  4820 * Improved 'oracle' command provides a type-safe interface to turn an
  4821 ML expression of type theory -> T -> term into a primitive rule of
  4822 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4823 is already included here); see also FOL/ex/IffExample.thy;
  4824 INCOMPATIBILITY.
  4825 
  4826 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4827 before); "cI" is no longer bound, use "c.intro" instead.
  4828 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4829 axclasses vs. locales.
  4830 
  4831 * Improved internal renaming of symbolic identifiers -- attach primes
  4832 instead of base 26 numbers.
  4833 
  4834 * New flag show_question_marks controls printing of leading question
  4835 marks in schematic variable names.
  4836 
  4837 * In schematic variable names, *any* symbol following \<^isub> or
  4838 \<^isup> is now treated as part of the base name.  For example, the
  4839 following works without printing of awkward ".0" indexes:
  4840 
  4841   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4842     by simp
  4843 
  4844 * Inner syntax includes (*(*nested*) comments*).
  4845 
  4846 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4847 annotations as "(00...)".
  4848 
  4849 * Clear separation of logical types and nonterminals, where the latter
  4850 may only occur in 'syntax' specifications or type abbreviations.
  4851 Before that distinction was only partially implemented via type class
  4852 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4853 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4854 exotic syntax specifications may require further adaption
  4855 (e.g. Cube/Cube.thy).
  4856 
  4857 * Removed obsolete type class "logic", use the top sort {} instead.
  4858 Note that non-logical types should be declared as 'nonterminals'
  4859 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4860 specifications.
  4861 
  4862 * Attributes 'induct' and 'cases': type or set names may now be
  4863 locally fixed variables as well.
  4864 
  4865 * Simplifier: can now control the depth to which conditional rewriting
  4866 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4867 Limit.
  4868 
  4869 * Simplifier: simplification procedures may now take the current
  4870 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4871 interface), which is very useful for calling the Simplifier
  4872 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4873 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4874 low-level mk_simproc no longer applies Logic.varify internally, to
  4875 allow for use in a context of fixed variables.
  4876 
  4877 * thin_tac now works even if the assumption being deleted contains !!
  4878 or ==>.  More generally, erule now works even if the major premise of
  4879 the elimination rule contains !! or ==>.
  4880 
  4881 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4882 
  4883 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4884 from Pure, which contains all common declarations already.  Both
  4885 theories are defined via plain Isabelle/Isar .thy files.
  4886 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4887 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4888 use isatool fixcpure to adapt your theory and ML sources.
  4889 
  4890 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4891 selections of theorems in named facts via index ranges.
  4892 
  4893 * 'print_theorems': in theory mode, really print the difference
  4894 wrt. the last state (works for interactive theory development only),
  4895 in proof mode print all local facts (cf. 'print_facts');
  4896 
  4897 * 'hide': option '(open)' hides only base names.
  4898 
  4899 * More efficient treatment of intermediate checkpoints in interactive
  4900 theory development.
  4901 
  4902 * Code generator is now invoked via code_module (incremental code
  4903 generation) and code_library (modular code generation, ML structures
  4904 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4905 must be quoted when used as identifiers.
  4906 
  4907 * New 'value' command for reading, evaluating and printing terms using
  4908 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4909 quoted when used as identifier.
  4910 
  4911 
  4912 *** Locales ***
  4913 
  4914 * New commands for the interpretation of locale expressions in
  4915 theories (1), locales (2) and proof contexts (3).  These generate
  4916 proof obligations from the expression specification.  After the
  4917 obligations have been discharged, theorems of the expression are added
  4918 to the theory, target locale or proof context.  The synopsis of the
  4919 commands is a follows:
  4920 
  4921   (1) interpretation expr inst
  4922   (2) interpretation target < expr
  4923   (3) interpret expr inst
  4924 
  4925 Interpretation in theories and proof contexts require a parameter
  4926 instantiation of terms from the current context.  This is applied to
  4927 specifications and theorems of the interpreted expression.
  4928 Interpretation in locales only permits parameter renaming through the
  4929 locale expression.  Interpretation is smart in that interpretations
  4930 that are active already do not occur in proof obligations, neither are
  4931 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4932 inspect active interpretations of a particular locale.  For details,
  4933 see the Isar Reference manual.  Examples can be found in
  4934 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4935 
  4936 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4937 'interpret' instead.
  4938 
  4939 * New context element 'constrains' for adding type constraints to
  4940 parameters.
  4941 
  4942 * Context expressions: renaming of parameters with syntax
  4943 redeclaration.
  4944 
  4945 * Locale declaration: 'includes' disallowed.
  4946 
  4947 * Proper static binding of attribute syntax -- i.e. types / terms /
  4948 facts mentioned as arguments are always those of the locale definition
  4949 context, independently of the context of later invocations.  Moreover,
  4950 locale operations (renaming and type / term instantiation) are applied
  4951 to attribute arguments as expected.
  4952 
  4953 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4954 actual attributes; rare situations may require Attrib.attribute to
  4955 embed those attributes into Attrib.src that lack concrete syntax.
  4956 Attribute implementations need to cooperate properly with the static
  4957 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4958 Attrib.XXX_thm etc. already do the right thing without further
  4959 intervention.  Only unusual applications -- such as "where" or "of"
  4960 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4961 on the context and the facts involved -- may have to assign parsed
  4962 values to argument tokens explicitly.
  4963 
  4964 * Changed parameter management in theorem generation for long goal
  4965 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4966 theorem statement in rare situations.
  4967 
  4968 * Locale inspection command 'print_locale' omits notes elements.  Use
  4969 'print_locale!' to have them included in the output.
  4970 
  4971 
  4972 *** Provers ***
  4973 
  4974 * Provers/hypsubst.ML: improved version of the subst method, for
  4975 single-step rewriting: it now works in bound variable contexts. New is
  4976 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  4977 rewrite a different subterm than the original subst method, which is
  4978 still available as 'simplesubst'.
  4979 
  4980 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  4981 and quasi orders.
  4982 
  4983 * Provers/trancl.ML: new transitivity reasoner for transitive and
  4984 reflexive-transitive closure of relations.
  4985 
  4986 * Provers/blast.ML: new reference depth_limit to make blast's depth
  4987 limit (previously hard-coded with a value of 20) user-definable.
  4988 
  4989 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  4990 is peformed already.  Object-logics merely need to finish their
  4991 initial simpset configuration as before.  INCOMPATIBILITY.
  4992 
  4993 
  4994 *** HOL ***
  4995 
  4996 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  4997 
  4998   syntax (epsilon)
  4999     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  5000 
  5001 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  5002 and x-symbol; use option '-m epsilon' to get it actually printed.
  5003 Moreover, the mathematically important symbolic identifier \<epsilon>
  5004 becomes available as variable, constant etc.  INCOMPATIBILITY,
  5005 
  5006 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  5007 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  5008 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  5009 support corresponding Isar calculations.
  5010 
  5011 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  5012 instead of ":".
  5013 
  5014 * theory SetInterval: changed the syntax for open intervals:
  5015 
  5016   Old       New
  5017   {..n(}    {..<n}
  5018   {)n..}    {n<..}
  5019   {m..n(}   {m..<n}
  5020   {)m..n}   {m<..n}
  5021   {)m..n(}  {m<..<n}
  5022 
  5023 The old syntax is still supported but will disappear in the next
  5024 release.  For conversion use the following Emacs search and replace
  5025 patterns (these are not perfect but work quite well):
  5026 
  5027   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  5028   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  5029 
  5030 * Theory Commutative_Ring (in Library): method comm_ring for proving
  5031 equalities in commutative rings; method 'algebra' provides a generic
  5032 interface.
  5033 
  5034 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  5035 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  5036 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  5037 be a tuple pattern.
  5038 
  5039 Some new syntax forms are available:
  5040 
  5041   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  5042   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  5043   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  5044   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  5045 
  5046 The latter form "\<Sum>x < k. e" used to be based on a separate
  5047 function "Summation", which has been discontinued.
  5048 
  5049 * theory Finite_Set: in structured induction proofs, the insert case
  5050 is now 'case (insert x F)' instead of the old counterintuitive 'case
  5051 (insert F x)'.
  5052 
  5053 * The 'refute' command has been extended to support a much larger
  5054 fragment of HOL, including axiomatic type classes, constdefs and
  5055 typedefs, inductive datatypes and recursion.
  5056 
  5057 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  5058 Requires zChaff with proof generation to be installed.  See
  5059 HOL/ex/SAT_Examples.thy for examples.
  5060 
  5061 * Datatype induction via method 'induct' now preserves the name of the
  5062 induction variable. For example, when proving P(xs::'a list) by
  5063 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  5064 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  5065 in unstructured proof scripts.
  5066 
  5067 * Reworked implementation of records.  Improved scalability for
  5068 records with many fields, avoiding performance problems for type
  5069 inference. Records are no longer composed of nested field types, but
  5070 of nested extension types. Therefore the record type only grows linear
  5071 in the number of extensions and not in the number of fields.  The
  5072 top-level (users) view on records is preserved.  Potential
  5073 INCOMPATIBILITY only in strange cases, where the theory depends on the
  5074 old record representation. The type generated for a record is called
  5075 <record_name>_ext_type.
  5076 
  5077 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  5078 proofs triggered by a record definition or a simproc (if
  5079 quick_and_dirty is enabled).  Definitions of large records can take
  5080 quite long.
  5081 
  5082 New simproc record_upd_simproc for simplification of multiple record
  5083 updates enabled by default.  Moreover, trivial updates are also
  5084 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  5085 occasionally, since simplification is more powerful by default.
  5086 
  5087 * typedef: proper support for polymorphic sets, which contain extra
  5088 type-variables in the term.
  5089 
  5090 * Simplifier: automatically reasons about transitivity chains
  5091 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  5092 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  5093 old proofs break occasionally as simplification may now solve more
  5094 goals than previously.
  5095 
  5096 * Simplifier: converts x <= y into x = y if assumption y <= x is
  5097 present.  Works for all partial orders (class "order"), in particular
  5098 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  5099 just like y <= x.
  5100 
  5101 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  5102 bound variable or a constant then the let is unfolded.  Otherwise
  5103 first a is simplified to b, and then f b is simplified to g. If
  5104 possible we abstract b from g arriving at "let x = b in h x",
  5105 otherwise we unfold the let and arrive at g.  The simproc can be
  5106 enabled/disabled by the reference use_let_simproc.  Potential
  5107 INCOMPATIBILITY since simplification is more powerful by default.
  5108 
  5109 * Classical reasoning: the meson method now accepts theorems as arguments.
  5110 
  5111 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  5112 jobs to provide advice on the provability of subgoals.
  5113 
  5114 * Theory OrderedGroup and Ring_and_Field: various additions and
  5115 improvements to faciliate calculations involving equalities and
  5116 inequalities.
  5117 
  5118 The following theorems have been eliminated or modified
  5119 (INCOMPATIBILITY):
  5120 
  5121   abs_eq             now named abs_of_nonneg
  5122   abs_of_ge_0        now named abs_of_nonneg
  5123   abs_minus_eq       now named abs_of_nonpos
  5124   imp_abs_id         now named abs_of_nonneg
  5125   imp_abs_neg_id     now named abs_of_nonpos
  5126   mult_pos           now named mult_pos_pos
  5127   mult_pos_le        now named mult_nonneg_nonneg
  5128   mult_pos_neg_le    now named mult_nonneg_nonpos
  5129   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  5130   mult_neg           now named mult_neg_neg
  5131   mult_neg_le        now named mult_nonpos_nonpos
  5132 
  5133 * The following lemmas in Ring_and_Field have been added to the simplifier:
  5134      
  5135      zero_le_square
  5136      not_square_less_zero 
  5137 
  5138   The following lemmas have been deleted from Real/RealPow:
  5139   
  5140      realpow_zero_zero
  5141      realpow_two
  5142      realpow_less
  5143      zero_le_power
  5144      realpow_two_le
  5145      abs_realpow_two
  5146      realpow_two_abs     
  5147 
  5148 * Theory Parity: added rules for simplifying exponents.
  5149 
  5150 * Theory List:
  5151 
  5152 The following theorems have been eliminated or modified
  5153 (INCOMPATIBILITY):
  5154 
  5155   list_all_Nil       now named list_all.simps(1)
  5156   list_all_Cons      now named list_all.simps(2)
  5157   list_all_conv      now named list_all_iff
  5158   set_mem_eq         now named mem_iff
  5159 
  5160 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  5161 asymptotic "big O" calculations.  See the notes in BigO.thy.
  5162 
  5163 
  5164 *** HOL-Complex ***
  5165 
  5166 * Theory RealDef: better support for embedding natural numbers and
  5167 integers in the reals.
  5168 
  5169 The following theorems have been eliminated or modified
  5170 (INCOMPATIBILITY):
  5171 
  5172   exp_ge_add_one_self  now requires no hypotheses
  5173   real_of_int_add      reversed direction of equality (use [symmetric])
  5174   real_of_int_minus    reversed direction of equality (use [symmetric])
  5175   real_of_int_diff     reversed direction of equality (use [symmetric])
  5176   real_of_int_mult     reversed direction of equality (use [symmetric])
  5177 
  5178 * Theory RComplete: expanded support for floor and ceiling functions.
  5179 
  5180 * Theory Ln is new, with properties of the natural logarithm
  5181 
  5182 * Hyperreal: There is a new type constructor "star" for making
  5183 nonstandard types.  The old type names are now type synonyms:
  5184 
  5185   hypreal = real star
  5186   hypnat = nat star
  5187   hcomplex = complex star
  5188 
  5189 * Hyperreal: Many groups of similarly-defined constants have been
  5190 replaced by polymorphic versions (INCOMPATIBILITY):
  5191 
  5192   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  5193 
  5194   starset      <-- starsetNat, starsetC
  5195   *s*          <-- *sNat*, *sc*
  5196   starset_n    <-- starsetNat_n, starsetC_n
  5197   *sn*         <-- *sNatn*, *scn*
  5198   InternalSets <-- InternalNatSets, InternalCSets
  5199 
  5200   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  5201   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  5202   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  5203   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  5204   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  5205 
  5206 * Hyperreal: Many type-specific theorems have been removed in favor of
  5207 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  5208 
  5209   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  5210   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  5211   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  5212   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  5213   right_minus <-- hypreal_add_minus
  5214   left_minus <-- {hypreal,hcomplex}_add_minus_left
  5215   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  5216   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  5217   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  5218   mult_1_right <-- hcomplex_mult_one_right
  5219   mult_zero_left <-- hcomplex_mult_zero_left
  5220   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  5221   right_distrib <-- hypnat_add_mult_distrib2
  5222   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  5223   right_inverse <-- hypreal_mult_inverse
  5224   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  5225   order_refl <-- {hypreal,hypnat}_le_refl
  5226   order_trans <-- {hypreal,hypnat}_le_trans
  5227   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  5228   order_less_le <-- {hypreal,hypnat}_less_le
  5229   linorder_linear <-- {hypreal,hypnat}_le_linear
  5230   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  5231   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  5232   add_nonneg_nonneg <-- hypreal_le_add_order
  5233 
  5234 * Hyperreal: Separate theorems having to do with type-specific
  5235 versions of constants have been merged into theorems that apply to the
  5236 new polymorphic constants (INCOMPATIBILITY):
  5237 
  5238   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  5239   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  5240   STAR_Un <-- {STAR,NatStar,STARC}_Un
  5241   STAR_Int <-- {STAR,NatStar,STARC}_Int
  5242   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  5243   STAR_subset <-- {STAR,NatStar,STARC}_subset
  5244   STAR_mem <-- {STAR,NatStar,STARC}_mem
  5245   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  5246   STAR_diff <-- {STAR,STARC}_diff
  5247   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  5248     STARC_hcomplex_of_complex}_image_subset
  5249   starset_n_Un <-- starset{Nat,C}_n_Un
  5250   starset_n_Int <-- starset{Nat,C}_n_Int
  5251   starset_n_Compl <-- starset{Nat,C}_n_Compl
  5252   starset_n_diff <-- starset{Nat,C}_n_diff
  5253   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  5254   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  5255   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  5256   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  5257   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  5258   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  5259   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  5260   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  5261   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  5262   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  5263   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  5264   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  5265   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  5266   starfun_diff <-- starfun{C,RC,CR}_diff
  5267   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  5268   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  5269   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  5270   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  5271   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  5272   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  5273   starfun_Id <-- starfunC_Id
  5274   starfun_approx <-- starfun{Nat,CR}_approx
  5275   starfun_capprox <-- starfun{C,RC}_capprox
  5276   starfun_abs <-- starfunNat_rabs
  5277   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  5278   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  5279   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  5280   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  5281   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  5282   starfun_add_approx <-- starfunCR_add_approx
  5283   starfun_inverse_inverse <-- starfunC_inverse_inverse
  5284   starfun_divide <-- starfun{C,CR,RC}_divide
  5285   starfun_n <-- starfun{Nat,C}_n
  5286   starfun_n_mult <-- starfun{Nat,C}_n_mult
  5287   starfun_n_add <-- starfun{Nat,C}_n_add
  5288   starfun_n_add_minus <-- starfunNat_n_add_minus
  5289   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  5290   starfun_n_minus <-- starfun{Nat,C}_n_minus
  5291   starfun_n_eq <-- starfun{Nat,C}_n_eq
  5292 
  5293   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  5294   star_n_minus <-- {hypreal,hcomplex}_minus
  5295   star_n_diff <-- {hypreal,hcomplex}_diff
  5296   star_n_mult <-- {hypreal,hcomplex}_mult
  5297   star_n_inverse <-- {hypreal,hcomplex}_inverse
  5298   star_n_le <-- {hypreal,hypnat}_le
  5299   star_n_less <-- {hypreal,hypnat}_less
  5300   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  5301   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  5302   star_n_abs <-- hypreal_hrabs
  5303   star_n_divide <-- hcomplex_divide
  5304 
  5305   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  5306   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  5307   star_of_diff <-- hypreal_of_real_diff
  5308   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  5309   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  5310   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  5311   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  5312   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  5313   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  5314   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  5315   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  5316   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  5317   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  5318   star_of_number_of <-- {hypreal,hcomplex}_number_of
  5319   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  5320   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  5321   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  5322   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  5323   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  5324   star_of_power <-- hypreal_of_real_power
  5325   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  5326 
  5327 * Hyperreal: new method "transfer" that implements the transfer
  5328 principle of nonstandard analysis. With a subgoal that mentions
  5329 nonstandard types like "'a star", the command "apply transfer"
  5330 replaces it with an equivalent one that mentions only standard types.
  5331 To be successful, all free variables must have standard types; non-
  5332 standard variables must have explicit universal quantifiers.
  5333 
  5334 * Hyperreal: A theory of Taylor series.
  5335 
  5336 
  5337 *** HOLCF ***
  5338 
  5339 * Discontinued special version of 'constdefs' (which used to support
  5340 continuous functions) in favor of the general Pure one with full
  5341 type-inference.
  5342 
  5343 * New simplification procedure for solving continuity conditions; it
  5344 is much faster on terms with many nested lambda abstractions (cubic
  5345 instead of exponential time).
  5346 
  5347 * New syntax for domain package: selector names are now optional.
  5348 Parentheses should be omitted unless argument is lazy, for example:
  5349 
  5350   domain 'a stream = cons "'a" (lazy "'a stream")
  5351 
  5352 * New command 'fixrec' for defining recursive functions with pattern
  5353 matching; defining multiple functions with mutual recursion is also
  5354 supported.  Patterns may include the constants cpair, spair, up, sinl,
  5355 sinr, or any data constructor defined by the domain package. The given
  5356 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  5357 syntax and examples.
  5358 
  5359 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  5360 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  5361 but the proof obligation additionally includes an admissibility
  5362 requirement. The packages generate instances of class cpo or pcpo,
  5363 with continuity and strictness theorems for Rep and Abs.
  5364 
  5365 * HOLCF: Many theorems have been renamed according to a more standard naming
  5366 scheme (INCOMPATIBILITY):
  5367 
  5368   foo_inject:  "foo$x = foo$y ==> x = y"
  5369   foo_eq:      "(foo$x = foo$y) = (x = y)"
  5370   foo_less:    "(foo$x << foo$y) = (x << y)"
  5371   foo_strict:  "foo$UU = UU"
  5372   foo_defined: "... ==> foo$x ~= UU"
  5373   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  5374 
  5375 
  5376 *** ZF ***
  5377 
  5378 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  5379 including the First Isomorphism Theorem (on quotienting by the kernel
  5380 of a homomorphism).
  5381 
  5382 * ZF/Simplifier: install second copy of type solver that actually
  5383 makes use of TC rules declared to Isar proof contexts (or locales);
  5384 the old version is still required for ML proof scripts.
  5385 
  5386 
  5387 *** Cube ***
  5388 
  5389 * Converted to Isar theory format; use locales instead of axiomatic
  5390 theories.
  5391 
  5392 
  5393 *** ML ***
  5394 
  5395 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  5396 for ||>, ||>>, |>>,
  5397 
  5398 * Pure/library.ML no longer defines its own option datatype, but uses
  5399 that of the SML basis, which has constructors NONE and SOME instead of
  5400 None and Some, as well as exception Option.Option instead of OPTION.
  5401 The functions the, if_none, is_some, is_none have been adapted
  5402 accordingly, while Option.map replaces apsome.
  5403 
  5404 * Pure/library.ML: the exception LIST has been given up in favour of
  5405 the standard exceptions Empty and Subscript, as well as
  5406 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  5407 superceded by the standard hd and tl functions etc.
  5408 
  5409 A number of basic list functions are no longer exported to the ML
  5410 toplevel, as they are variants of predefined functions.  The following
  5411 suggests how one can translate existing code:
  5412 
  5413     rev_append xs ys = List.revAppend (xs, ys)
  5414     nth_elem (i, xs) = List.nth (xs, i)
  5415     last_elem xs = List.last xs
  5416     flat xss = List.concat xss
  5417     seq fs = List.app fs
  5418     partition P xs = List.partition P xs
  5419     mapfilter f xs = List.mapPartial f xs
  5420 
  5421 * Pure/library.ML: several combinators for linear functional
  5422 transformations, notably reverse application and composition:
  5423 
  5424   x |> f                f #> g
  5425   (x, y) |-> f          f #-> g
  5426 
  5427 * Pure/library.ML: introduced/changed precedence of infix operators:
  5428 
  5429   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  5430   infix 2 ?;
  5431   infix 3 o oo ooo oooo;
  5432   infix 4 ~~ upto downto;
  5433 
  5434 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  5435 infix operators.
  5436 
  5437 * Pure/library.ML: natural list combinators fold, fold_rev, and
  5438 fold_map support linear functional transformations and nesting.  For
  5439 example:
  5440 
  5441   fold f [x1, ..., xN] y =
  5442     y |> f x1 |> ... |> f xN
  5443 
  5444   (fold o fold) f [xs1, ..., xsN] y =
  5445     y |> fold f xs1 |> ... |> fold f xsN
  5446 
  5447   fold f [x1, ..., xN] =
  5448     f x1 #> ... #> f xN
  5449 
  5450   (fold o fold) f [xs1, ..., xsN] =
  5451     fold f xs1 #> ... #> fold f xsN
  5452 
  5453 * Pure/library.ML: the following selectors on type 'a option are
  5454 available:
  5455 
  5456   the:               'a option -> 'a  (*partial*)
  5457   these:             'a option -> 'a  where 'a = 'b list
  5458   the_default: 'a -> 'a option -> 'a
  5459   the_list:          'a option -> 'a list
  5460 
  5461 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5462 basic operations for association lists, following natural argument
  5463 order; moreover the explicit equality predicate passed here avoids
  5464 potentially expensive polymorphic runtime equality checks.
  5465 The old functions may be expressed as follows:
  5466 
  5467   assoc = uncurry (AList.lookup (op =))
  5468   assocs = these oo AList.lookup (op =)
  5469   overwrite = uncurry (AList.update (op =)) o swap
  5470 
  5471 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5472 
  5473   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  5474   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  5475 
  5476 replacing make_keylist and keyfilter (occassionally used)
  5477 Naive rewrites:
  5478 
  5479   make_keylist = AList.make
  5480   keyfilter = AList.find (op =)
  5481 
  5482 * eq_fst and eq_snd now take explicit equality parameter, thus
  5483   avoiding eqtypes. Naive rewrites:
  5484 
  5485     eq_fst = eq_fst (op =)
  5486     eq_snd = eq_snd (op =)
  5487 
  5488 * Removed deprecated apl and apr (rarely used).
  5489   Naive rewrites:
  5490 
  5491     apl (n, op) =>>= curry op n
  5492     apr (op, m) =>>= fn n => op (n, m)
  5493 
  5494 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  5495 provides a reasonably efficient light-weight implementation of sets as
  5496 lists.
  5497 
  5498 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  5499 few new operations; existing lookup and update are now curried to
  5500 follow natural argument order (for use with fold etc.);
  5501 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  5502 
  5503 * Pure/General: output via the Isabelle channels of
  5504 writeln/warning/error etc. is now passed through Output.output, with a
  5505 hook for arbitrary transformations depending on the print_mode
  5506 (cf. Output.add_mode -- the first active mode that provides a output
  5507 function wins).  Already formatted output may be embedded into further
  5508 text via Output.raw; the result of Pretty.string_of/str_of and derived
  5509 functions (string_of_term/cterm/thm etc.) is already marked raw to
  5510 accommodate easy composition of diagnostic messages etc.  Programmers
  5511 rarely need to care about Output.output or Output.raw at all, with
  5512 some notable exceptions: Output.output is required when bypassing the
  5513 standard channels (writeln etc.), or in token translations to produce
  5514 properly formatted results; Output.raw is required when capturing
  5515 already output material that will eventually be presented to the user
  5516 a second time.  For the default print mode, both Output.output and
  5517 Output.raw have no effect.
  5518 
  5519 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  5520 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  5521 cumulative results are displayed at the end of a batch session.
  5522 
  5523 * Pure/General: File.sysify_path and File.quote_sysify path have been
  5524 replaced by File.platform_path and File.shell_path (with appropriate
  5525 hooks).  This provides a clean interface for unusual systems where the
  5526 internal and external process view of file names are different.
  5527 
  5528 * Pure: more efficient orders for basic syntactic entities: added
  5529 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  5530 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  5531 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  5532 orders now -- potential INCOMPATIBILITY for code that depends on a
  5533 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  5534 Library.sort_strings on result).
  5535 
  5536 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  5537 fold_types traverse types/terms from left to right, observing natural
  5538 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  5539 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  5540 
  5541 * Pure: name spaces have been refined, with significant changes of the
  5542 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  5543 to extern(_table).  The plain name entry path is superceded by a
  5544 general 'naming' context, which also includes the 'policy' to produce
  5545 a fully qualified name and external accesses of a fully qualified
  5546 name; NameSpace.extend is superceded by context dependent
  5547 Sign.declare_name.  Several theory and proof context operations modify
  5548 the naming context.  Especially note Theory.restore_naming and
  5549 ProofContext.restore_naming to get back to a sane state; note that
  5550 Theory.add_path is no longer sufficient to recover from
  5551 Theory.absolute_path in particular.
  5552 
  5553 * Pure: new flags short_names (default false) and unique_names
  5554 (default true) for controlling output of qualified names.  If
  5555 short_names is set, names are printed unqualified.  If unique_names is
  5556 reset, the name prefix is reduced to the minimum required to achieve
  5557 the original result when interning again, even if there is an overlap
  5558 with earlier declarations.
  5559 
  5560 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  5561 now 'extend', and 'merge' gets an additional Pretty.pp argument
  5562 (useful for printing error messages).  INCOMPATIBILITY.
  5563 
  5564 * Pure: major reorganization of the theory context.  Type Sign.sg and
  5565 Theory.theory are now identified, referring to the universal
  5566 Context.theory (see Pure/context.ML).  Actual signature and theory
  5567 content is managed as theory data.  The old code and interfaces were
  5568 spread over many files and structures; the new arrangement introduces
  5569 considerable INCOMPATIBILITY to gain more clarity:
  5570 
  5571   Context -- theory management operations (name, identity, inclusion,
  5572     parents, ancestors, merge, etc.), plus generic theory data;
  5573 
  5574   Sign -- logical signature and syntax operations (declaring consts,
  5575     types, etc.), plus certify/read for common entities;
  5576 
  5577   Theory -- logical theory operations (stating axioms, definitions,
  5578     oracles), plus a copy of logical signature operations (consts,
  5579     types, etc.); also a few basic management operations (Theory.copy,
  5580     Theory.merge, etc.)
  5581 
  5582 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  5583 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  5584 for convenience -- they merely return the theory.
  5585 
  5586 * Pure: type Type.tsig is superceded by theory in most interfaces.
  5587 
  5588 * Pure: the Isar proof context type is already defined early in Pure
  5589 as Context.proof (note that ProofContext.context and Proof.context are
  5590 aliases, where the latter is the preferred name).  This enables other
  5591 Isabelle components to refer to that type even before Isar is present.
  5592 
  5593 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  5594 typeK, constK, axiomK, oracleK), but provide explicit operations for
  5595 any of these kinds.  For example, Sign.intern typeK is now
  5596 Sign.intern_type, Theory.hide_space Sign.typeK is now
  5597 Theory.hide_types.  Also note that former
  5598 Theory.hide_classes/types/consts are now
  5599 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  5600 internalize their arguments!  INCOMPATIBILITY.
  5601 
  5602 * Pure: get_thm interface (of PureThy and ProofContext) expects
  5603 datatype thmref (with constructors Name and NameSelection) instead of
  5604 plain string -- INCOMPATIBILITY;
  5605 
  5606 * Pure: cases produced by proof methods specify options, where NONE
  5607 means to remove case bindings -- INCOMPATIBILITY in
  5608 (RAW_)METHOD_CASES.
  5609 
  5610 * Pure: the following operations retrieve axioms or theorems from a
  5611 theory node or theory hierarchy, respectively:
  5612 
  5613   Theory.axioms_of: theory -> (string * term) list
  5614   Theory.all_axioms_of: theory -> (string * term) list
  5615   PureThy.thms_of: theory -> (string * thm) list
  5616   PureThy.all_thms_of: theory -> (string * thm) list
  5617 
  5618 * Pure: print_tac now outputs the goal through the trace channel.
  5619 
  5620 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  5621 Reference Toplevel.debug (default false) controls detailed printing
  5622 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  5623 controls execution profiling -- set to 1 for time and 2 for space
  5624 (both increase the runtime).
  5625 
  5626 * Isar session: The initial use of ROOT.ML is now always timed,
  5627 i.e. the log will show the actual process times, in contrast to the
  5628 elapsed wall-clock time that the outer shell wrapper produces.
  5629 
  5630 * Simplifier: improved handling of bound variables (nameless
  5631 representation, avoid allocating new strings).  Simprocs that invoke
  5632 the Simplifier recursively should use Simplifier.inherit_bounds to
  5633 avoid local name clashes.  Failure to do so produces warnings
  5634 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  5635 for further details.
  5636 
  5637 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  5638 bindings for all theorems stored within a given theory; this may help
  5639 in porting non-Isar theories to Isar ones, while keeping ML proof
  5640 scripts for the time being.
  5641 
  5642 * ML operator HTML.with_charset specifies the charset begin used for
  5643 generated HTML files.  For example:
  5644 
  5645   HTML.with_charset "utf-8" use_thy "Hebrew";
  5646   HTML.with_charset "utf-8" use_thy "Chinese";
  5647 
  5648 
  5649 *** System ***
  5650 
  5651 * Allow symlinks to all proper Isabelle executables (Isabelle,
  5652 isabelle, isatool etc.).
  5653 
  5654 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  5655 isatool doc, isatool mkdir, display_drafts etc.).
  5656 
  5657 * isatool usedir: option -f allows specification of the ML file to be
  5658 used by Isabelle; default is ROOT.ML.
  5659 
  5660 * New isatool version outputs the version identifier of the Isabelle
  5661 distribution being used.
  5662 
  5663 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  5664 (containing Boolean satisfiability problems) into Isabelle/HOL
  5665 theories.
  5666 
  5667 
  5668 
  5669 New in Isabelle2004 (April 2004)
  5670 --------------------------------
  5671 
  5672 *** General ***
  5673 
  5674 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  5675   Replaces linorder.ML.
  5676 
  5677 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  5678   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  5679   (\<a>...\<z>), are now considered normal letters, and can therefore
  5680   be used anywhere where an ASCII letter (a...zA...Z) has until
  5681   now. COMPATIBILITY: This obviously changes the parsing of some
  5682   terms, especially where a symbol has been used as a binder, say
  5683   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  5684   as an identifier.  Fix it by inserting a space around former
  5685   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  5686   existing theory and ML files.
  5687 
  5688 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  5689 
  5690 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  5691   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  5692   a normal (but invisible) letter. For multiple letter subscripts repeat
  5693   \<^isub> like this: x\<^isub>1\<^isub>2.
  5694 
  5695 * Pure: There are now sub-/superscripts that can span more than one
  5696   character. Text between \<^bsub> and \<^esub> is set in subscript in
  5697   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  5698   superscript. The new control characters are not identifier parts.
  5699 
  5700 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5701   content of "..." to the latex file instead of \isacntrl... . The "..."
  5702   may consist of any printable characters excluding the end bracket >.
  5703 
  5704 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5705   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5706   declare constants "final", which prevents their being given a definition
  5707   later.  It is useful for constants whose behaviour is fixed axiomatically
  5708   rather than definitionally, such as the meta-logic connectives.
  5709 
  5710 * Pure: 'instance' now handles general arities with general sorts
  5711   (i.e. intersections of classes),
  5712 
  5713 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5714   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5715   It can be changed to alter the colors/layout of generated pages.
  5716 
  5717 
  5718 *** Isar ***
  5719 
  5720 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5721   cut_tac, subgoal_tac and thin_tac:
  5722   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5723     locales are no longer forced to write Isar proof scripts.
  5724     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5725     emulations.
  5726   - INCOMPATIBILITY: names of variables to be instantiated may no
  5727     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5728     This is consistent with the instantiation attribute "where".
  5729 
  5730 * Attributes "where" and "of":
  5731   - Now take type variables of instantiated theorem into account when reading
  5732     the instantiation string.  This fixes a bug that caused instantiated
  5733     theorems to have too special types in some circumstances.
  5734   - "where" permits explicit instantiations of type variables.
  5735 
  5736 * Calculation commands "moreover" and "also" no longer interfere with
  5737   current facts ("this"), admitting arbitrary combinations with "then"
  5738   and derived forms.
  5739 
  5740 * Locales:
  5741   - Goal statements involving the context element "includes" no longer
  5742     generate theorems with internal delta predicates (those ending on
  5743     "_axioms") in the premise.
  5744     Resolve particular premise with <locale>.intro to obtain old form.
  5745   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5746     specification and "includes" elements in goal statement.
  5747   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5748     [intro?] and [elim?] (respectively) by default.
  5749   - Experimental command for instantiation of locales in proof contexts:
  5750         instantiate <label>[<attrs>]: <loc>
  5751     Instantiates locale <loc> and adds all its theorems to the current context
  5752     taking into account their attributes.  Label and attrs are optional
  5753     modifiers, like in theorem declarations.  If present, names of
  5754     instantiated theorems are qualified with <label>, and the attributes
  5755     <attrs> are applied after any attributes these theorems might have already.
  5756       If the locale has assumptions, a chained fact of the form
  5757     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5758     are derived.  The command does not support old-style locales declared
  5759     with "locale (open)".
  5760       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5761 
  5762 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5763   (Isar) contexts.
  5764 
  5765 
  5766 *** HOL ***
  5767 
  5768 * Proof import: new image HOL4 contains the imported library from
  5769   the HOL4 system with about 2500 theorems. It is imported by
  5770   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5771   can be used like any other Isabelle image.  See
  5772   HOL/Import/HOL/README for more information.
  5773 
  5774 * Simplifier:
  5775   - Much improved handling of linear and partial orders.
  5776     Reasoners for linear and partial orders are set up for type classes
  5777     "linorder" and "order" respectively, and are added to the default simpset
  5778     as solvers.  This means that the simplifier can build transitivity chains
  5779     to solve goals from the assumptions.
  5780   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5781     of blast or auto after simplification become unnecessary because the goal
  5782     is solved by simplification already.
  5783 
  5784 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5785     all proved in axiomatic type classes for semirings, rings and fields.
  5786 
  5787 * Numerics:
  5788   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5789     now formalized using the Ring_and_Field theory mentioned above.
  5790   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5791     than before, because now they are set up once in a generic manner.
  5792   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5793     Look for the general versions in Ring_and_Field (and Power if they concern
  5794     exponentiation).
  5795 
  5796 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5797 
  5798 * Records:
  5799   - Record types are now by default printed with their type abbreviation
  5800     instead of the list of all field types. This can be configured via
  5801     the reference "print_record_type_abbr".
  5802   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5803     (not enabled by default).
  5804   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5805     EX x. x = sel r to True (not enabled by default).
  5806   - Tactic "record_split_simp_tac" to split and simplify records added.
  5807 
  5808 * 'specification' command added, allowing for definition by
  5809   specification.  There is also an 'ax_specification' command that
  5810   introduces the new constants axiomatically.
  5811 
  5812 * arith(_tac) is now able to generate counterexamples for reals as well.
  5813 
  5814 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5815 
  5816 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5817   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5818 
  5819 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5820   matrix theory to linear programming.
  5821 
  5822 * Unions and Intersections:
  5823   The latex output syntax of UN and INT has been changed
  5824   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5825   i.e. the index formulae has become a subscript.
  5826   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5827 
  5828 * Unions and Intersections over Intervals:
  5829   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5830   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5831   like in normal math, and corresponding versions for < and for intersection.
  5832 
  5833 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5834   lexicographic dictonary ordering has been added as "lexord".
  5835 
  5836 * ML: the legacy theory structures Int and List have been removed. They had
  5837   conflicted with ML Basis Library structures having the same names.
  5838 
  5839 * 'refute' command added to search for (finite) countermodels.  Only works
  5840   for a fragment of HOL.  The installation of an external SAT solver is
  5841   highly recommended.  See "HOL/Refute.thy" for details.
  5842 
  5843 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5844   formulae under an assignment of free variables to random values.
  5845   In contrast to 'refute', it can deal with inductive datatypes,
  5846   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5847   for examples.
  5848 
  5849 
  5850 *** HOLCF ***
  5851 
  5852 * Streams now come with concatenation and are part of the HOLCF image
  5853 
  5854 
  5855 
  5856 New in Isabelle2003 (May 2003)
  5857 ------------------------------
  5858 
  5859 *** General ***
  5860 
  5861 * Provers/simplifier:
  5862 
  5863   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5864     Assumptions are now subject to complete mutual simplification,
  5865     not just from left to right. The simplifier now preserves
  5866     the order of assumptions.
  5867 
  5868     Potential INCOMPATIBILITY:
  5869 
  5870     -- simp sometimes diverges where the old version did
  5871        not, e.g. invoking simp on the goal
  5872 
  5873         [| P (f x); y = x; f x = f y |] ==> Q
  5874 
  5875        now gives rise to the infinite reduction sequence
  5876 
  5877         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5878 
  5879        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5880        kind of problem.
  5881 
  5882     -- Tactics combining classical reasoner and simplification (such as auto)
  5883        are also affected by this change, because many of them rely on
  5884        simp. They may sometimes diverge as well or yield a different numbers
  5885        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5886        in case of problems. Sometimes subsequent calls to the classical
  5887        reasoner will fail because a preceeding call to the simplifier too
  5888        eagerly simplified the goal, e.g. deleted redundant premises.
  5889 
  5890   - The simplifier trace now shows the names of the applied rewrite rules
  5891 
  5892   - You can limit the number of recursive invocations of the simplifier
  5893     during conditional rewriting (where the simplifie tries to solve the
  5894     conditions before applying the rewrite rule):
  5895     ML "simp_depth_limit := n"
  5896     where n is an integer. Thus you can force termination where previously
  5897     the simplifier would diverge.
  5898 
  5899   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5900 
  5901   - No longer aborts on failed congruence proof.  Instead, the
  5902     congruence is ignored.
  5903 
  5904 * Pure: New generic framework for extracting programs from constructive
  5905   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5906   as HOL/Extraction for some case studies.
  5907 
  5908 * Pure: The main goal of the proof state is no longer shown by default, only
  5909 the subgoals. This behaviour is controlled by a new flag.
  5910    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5911 (ML: Proof.show_main_goal).
  5912 
  5913 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5914 rules whose conclusion matches subgoal 1:
  5915       PG menu: Isabelle/Isar -> Show me -> matching rules
  5916 The rules are ordered by how closely they match the subgoal.
  5917 In particular, rules that solve a subgoal outright are displayed first
  5918 (or rather last, the way they are printed).
  5919 (ML: ProofGeneral.print_intros())
  5920 
  5921 * Pure: New flag trace_unify_fail causes unification to print
  5922 diagnostic information (PG: in trace buffer) when it fails. This is
  5923 useful for figuring out why single step proofs like rule, erule or
  5924 assumption failed.
  5925 
  5926 * Pure: Locale specifications now produce predicate definitions
  5927 according to the body of text (covering assumptions modulo local
  5928 definitions); predicate "loc_axioms" covers newly introduced text,
  5929 while "loc" is cumulative wrt. all included locale expressions; the
  5930 latter view is presented only on export into the global theory
  5931 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5932 on the old view without predicates;
  5933 
  5934 * Pure: predefined locales "var" and "struct" are useful for sharing
  5935 parameters (as in CASL, for example); just specify something like
  5936 ``var x + var y + struct M'' as import;
  5937 
  5938 * Pure: improved thms_containing: proper indexing of facts instead of
  5939 raw theorems; check validity of results wrt. current name space;
  5940 include local facts of proof configuration (also covers active
  5941 locales), cover fixed variables in index; may use "_" in term
  5942 specification; an optional limit for the number of printed facts may
  5943 be given (the default is 40);
  5944 
  5945 * Pure: disallow duplicate fact bindings within new-style theory files
  5946 (batch-mode only);
  5947 
  5948 * Provers: improved induct method: assumptions introduced by case
  5949 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5950 the goal statement); "foo" still refers to all facts collectively;
  5951 
  5952 * Provers: the function blast.overloaded has been removed: all constants
  5953 are regarded as potentially overloaded, which improves robustness in exchange
  5954 for slight decrease in efficiency;
  5955 
  5956 * Provers/linorder: New generic prover for transitivity reasoning over
  5957 linear orders.  Note: this prover is not efficient!
  5958 
  5959 * Isar: preview of problems to finish 'show' now produce an error
  5960 rather than just a warning (in interactive mode);
  5961 
  5962 
  5963 *** HOL ***
  5964 
  5965 * arith(_tac)
  5966 
  5967  - Produces a counter example if it cannot prove a goal.
  5968    Note that the counter example may be spurious if the goal is not a formula
  5969    of quantifier-free linear arithmetic.
  5970    In ProofGeneral the counter example appears in the trace buffer.
  5971 
  5972  - Knows about div k and mod k where k is a numeral of type nat or int.
  5973 
  5974  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  5975    linear arithmetic fails. This takes account of quantifiers and divisibility.
  5976    Presburger arithmetic can also be called explicitly via presburger(_tac).
  5977 
  5978 * simp's arithmetic capabilities have been enhanced a bit: it now
  5979 takes ~= in premises into account (by performing a case split);
  5980 
  5981 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  5982 are distributed over a sum of terms;
  5983 
  5984 * New tactic "trans_tac" and method "trans" instantiate
  5985 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  5986 "<=", "<" and "=").
  5987 
  5988 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  5989 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  5990 
  5991 * 'typedef' command has new option "open" to suppress the set
  5992 definition;
  5993 
  5994 * functions Min and Max on finite sets have been introduced (theory
  5995 Finite_Set);
  5996 
  5997 * attribute [symmetric] now works for relations as well; it turns
  5998 (x,y) : R^-1 into (y,x) : R, and vice versa;
  5999 
  6000 * induct over a !!-quantified statement (say !!x1..xn):
  6001   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  6002 
  6003 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  6004 %x. None. Warning: empty_def now refers to the previously hidden definition
  6005 of the empty set.
  6006 
  6007 * Algebra: formalization of classical algebra.  Intended as base for
  6008 any algebraic development in Isabelle.  Currently covers group theory
  6009 (up to Sylow's theorem) and ring theory (Universal Property of
  6010 Univariate Polynomials).  Contributions welcome;
  6011 
  6012 * GroupTheory: deleted, since its material has been moved to Algebra;
  6013 
  6014 * Complex: new directory of the complex numbers with numeric constants,
  6015 nonstandard complex numbers, and some complex analysis, standard and
  6016 nonstandard (Jacques Fleuriot);
  6017 
  6018 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  6019 
  6020 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  6021 Fleuriot);
  6022 
  6023 * Real/HahnBanach: updated and adapted to locales;
  6024 
  6025 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  6026 Gray and Kramer);
  6027 
  6028 * UNITY: added the Meier-Sanders theory of progress sets;
  6029 
  6030 * MicroJava: bytecode verifier and lightweight bytecode verifier
  6031 as abstract algorithms, instantiated to the JVM;
  6032 
  6033 * Bali: Java source language formalization. Type system, operational
  6034 semantics, axiomatic semantics. Supported language features:
  6035 classes, interfaces, objects,virtual methods, static methods,
  6036 static/instance fields, arrays, access modifiers, definite
  6037 assignment, exceptions.
  6038 
  6039 
  6040 *** ZF ***
  6041 
  6042 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  6043 universe, etc.);
  6044 
  6045 * Main ZF: virtually all theories converted to new-style format;
  6046 
  6047 
  6048 *** ML ***
  6049 
  6050 * Pure: Tactic.prove provides sane interface for internal proofs;
  6051 omits the infamous "standard" operation, so this is more appropriate
  6052 than prove_goalw_cterm in many situations (e.g. in simprocs);
  6053 
  6054 * Pure: improved error reporting of simprocs;
  6055 
  6056 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  6057 up simprocs;
  6058 
  6059 
  6060 *** Document preparation ***
  6061 
  6062 * uses \par instead of \\ for line breaks in theory text. This may
  6063 shift some page breaks in large documents. To get the old behaviour
  6064 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  6065 
  6066 * minimized dependencies of isabelle.sty and isabellesym.sty on
  6067 other packages
  6068 
  6069 * \<euro> now needs package babel/greek instead of marvosym (which
  6070 broke \Rightarrow)
  6071 
  6072 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  6073 textcomp package)
  6074 
  6075 
  6076 
  6077 New in Isabelle2002 (March 2002)
  6078 --------------------------------
  6079 
  6080 *** Document preparation ***
  6081 
  6082 * greatly simplified document preparation setup, including more
  6083 graceful interpretation of isatool usedir -i/-d/-D options, and more
  6084 instructive isatool mkdir; users should basically be able to get
  6085 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  6086 users may run a separate document processing stage manually like this:
  6087 "isatool usedir -D output HOL Test && isatool document Test/output";
  6088 
  6089 * theory dependency graph may now be incorporated into documents;
  6090 isatool usedir -g true will produce session_graph.eps/.pdf for use
  6091 with \includegraphics of LaTeX;
  6092 
  6093 * proper spacing of consecutive markup elements, especially text
  6094 blocks after section headings;
  6095 
  6096 * support bold style (for single symbols only), input syntax is like
  6097 this: "\<^bold>\<alpha>" or "\<^bold>A";
  6098 
  6099 * \<bullet> is now output as bold \cdot by default, which looks much
  6100 better in printed text;
  6101 
  6102 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  6103 note that these symbols are currently unavailable in Proof General /
  6104 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  6105 
  6106 * isatool latex no longer depends on changed TEXINPUTS, instead
  6107 isatool document copies the Isabelle style files to the target
  6108 location;
  6109 
  6110 
  6111 *** Isar ***
  6112 
  6113 * Pure/Provers: improved proof by cases and induction;
  6114   - 'case' command admits impromptu naming of parameters (such as
  6115     "case (Suc n)");
  6116   - 'induct' method divinates rule instantiation from the inductive
  6117     claim; no longer requires excessive ?P bindings for proper
  6118     instantiation of cases;
  6119   - 'induct' method properly enumerates all possibilities of set/type
  6120     rules; as a consequence facts may be also passed through *type*
  6121     rules without further ado;
  6122   - 'induct' method now derives symbolic cases from the *rulified*
  6123     rule (before it used to rulify cases stemming from the internal
  6124     atomized version); this means that the context of a non-atomic
  6125     statement becomes is included in the hypothesis, avoiding the
  6126     slightly cumbersome show "PROP ?case" form;
  6127   - 'induct' may now use elim-style induction rules without chaining
  6128     facts, using ``missing'' premises from the goal state; this allows
  6129     rules stemming from inductive sets to be applied in unstructured
  6130     scripts, while still benefitting from proper handling of non-atomic
  6131     statements; NB: major inductive premises need to be put first, all
  6132     the rest of the goal is passed through the induction;
  6133   - 'induct' proper support for mutual induction involving non-atomic
  6134     rule statements (uses the new concept of simultaneous goals, see
  6135     below);
  6136   - append all possible rule selections, but only use the first
  6137     success (no backtracking);
  6138   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  6139   - undeclared rule case names default to numbers 1, 2, 3, ...;
  6140   - added 'print_induct_rules' (covered by help item in recent Proof
  6141     General versions);
  6142   - moved induct/cases attributes to Pure, methods to Provers;
  6143   - generic method setup instantiated for FOL and HOL;
  6144 
  6145 * Pure: support multiple simultaneous goal statements, for example
  6146 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  6147 meta-level mechanism, this acts as if several individual goals had
  6148 been stated separately; in particular common proof methods need to be
  6149 repeated in order to cover all claims; note that a single elimination
  6150 step is *not* sufficient to establish the two conjunctions, so this
  6151 fails:
  6152 
  6153   assume "A & B" then have A and B ..   (*".." fails*)
  6154 
  6155 better use "obtain" in situations as above; alternative refer to
  6156 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  6157 
  6158 * Pure: proper integration with ``locales''; unlike the original
  6159 version by Florian Kammller, Isar locales package high-level proof
  6160 contexts rather than raw logical ones (e.g. we admit to include
  6161 attributes everywhere); operations on locales include merge and
  6162 rename; support for implicit arguments (``structures''); simultaneous
  6163 type-inference over imports and text; see also HOL/ex/Locales.thy for
  6164 some examples;
  6165 
  6166 * Pure: the following commands have been ``localized'', supporting a
  6167 target locale specification "(in name)": 'lemma', 'theorem',
  6168 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  6169 stored both within the locale and at the theory level (exported and
  6170 qualified by the locale name);
  6171 
  6172 * Pure: theory goals may now be specified in ``long'' form, with
  6173 ad-hoc contexts consisting of arbitrary locale elements. for example
  6174 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  6175 definitions may be given, too); the result is a meta-level rule with
  6176 the context elements being discharged in the obvious way;
  6177 
  6178 * Pure: new proof command 'using' allows to augment currently used
  6179 facts after a goal statement ('using' is syntactically analogous to
  6180 'apply', but acts on the goal's facts only); this allows chained facts
  6181 to be separated into parts given before and after a claim, as in
  6182 ``from a and b have C using d and e <proof>'';
  6183 
  6184 * Pure: renamed "antecedent" case to "rule_context";
  6185 
  6186 * Pure: new 'judgment' command records explicit information about the
  6187 object-logic embedding (used by several tools internally); no longer
  6188 use hard-wired "Trueprop";
  6189 
  6190 * Pure: added 'corollary' command;
  6191 
  6192 * Pure: fixed 'token_translation' command;
  6193 
  6194 * Pure: removed obsolete 'exported' attribute;
  6195 
  6196 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  6197 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  6198 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  6199 
  6200 * Pure: method 'atomize' presents local goal premises as object-level
  6201 statements (atomic meta-level propositions); setup controlled via
  6202 rewrite rules declarations of 'atomize' attribute; example
  6203 application: 'induct' method with proper rule statements in improper
  6204 proof *scripts*;
  6205 
  6206 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  6207 now consider the syntactic context of assumptions, giving a better
  6208 chance to get type-inference of the arguments right (this is
  6209 especially important for locales);
  6210 
  6211 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  6212 mode;
  6213 
  6214 * Pure/obtain: the formal conclusion "thesis", being marked as
  6215 ``internal'', may no longer be reference directly in the text;
  6216 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  6217 situations;
  6218 
  6219 * Pure: generic 'sym' attribute which declares a rule both as pure
  6220 'elim?' and for the 'symmetric' operation;
  6221 
  6222 * Pure: marginal comments ``--'' may now occur just anywhere in the
  6223 text; the fixed correlation with particular command syntax has been
  6224 discontinued;
  6225 
  6226 * Pure: new method 'rules' is particularly well-suited for proof
  6227 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  6228 but often produces more compact proof terms with less detours;
  6229 
  6230 * Pure/Provers/classical: simplified integration with pure rule