NEWS
author wenzelm
Mon Mar 21 21:16:39 2011 +0100 (2011-03-21)
changeset 42045 fda09013c496
parent 42015 7b6e72a1b7dd
child 42056 160a630b2c7e
permissions -rw-r--r--
tuned;
     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) is has been
    26 discontinued.  INCOMPATIBILITY.
    27 
    28 * Various optional external tools are referenced more robustly and
    29 uniformly by explicit Isabelle settings as follows:
    30 
    31   ISABELLE_CSDP   (formerly CSDP_EXE)
    32   ISABELLE_GHC    (formerly EXEC_GHC or GHC_PATH)
    33   ISABELLE_OCAML  (formerly EXEC_OCAML)
    34   ISABELLE_SWIPL  (formerly EXEC_SWIPL)
    35   ISABELLE_YAP    (formerly EXEC_YAP)
    36 
    37 Note that automated detection from the file-system or search path has
    38 been discontinued.  INCOMPATIBILITY.
    39 
    40 
    41 *** HOL ***
    42 
    43 * Nitpick:
    44   - Added "need" and "total_consts" options.
    45   - Reintroduced "show_skolems" option by popular demand.
    46   - Renamed attribute: nitpick_def ~> nitpick_unfold.
    47     INCOMPATIBILITY.
    48 
    49 * Sledgehammer:
    50   - sledgehammer available_provers ~> sledgehammer supported_provers
    51     INCOMPATIBILITY.
    52 
    53 * "try":
    54   - Added "simp:", "intro:", and "elim:" options.
    55 
    56 * Function package: discontinued option "tailrec".
    57 INCOMPATIBILITY. Use partial_function instead.
    58 
    59 
    60 *** Document preparation ***
    61 
    62 * New term style "isub" as ad-hoc conversion of variables x1, y23 into
    63 subscripted form x\<^isub>1, y\<^isub>2\<^isub>3.
    64 
    65 
    66 *** ML ***
    67 
    68 * Structure Timing provides various operations for timing; supersedes
    69 former start_timing/end_timing etc.
    70 
    71 * Path.print is the official way to show file-system paths to users
    72 (including quotes etc.).
    73 
    74 
    75 
    76 New in Isabelle2011 (January 2011)
    77 ----------------------------------
    78 
    79 *** General ***
    80 
    81 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
    82 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
    83 useful tooltips and hyperlinks produced from its static analysis.  The
    84 bundled component provides an executable Isabelle tool that can be run
    85 like this:
    86 
    87   Isabelle2011/bin/isabelle jedit
    88 
    89 * Significantly improved Isabelle/Isar implementation manual.
    90 
    91 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
    92 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
    93 while the default heap location within that directory lacks that extra
    94 suffix.  This isolates multiple Isabelle installations from each
    95 other, avoiding problems with old settings in new versions.
    96 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
    97 
    98 * Source files are always encoded as UTF-8, instead of old-fashioned
    99 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
   100 the following package declarations:
   101 
   102   \usepackage[utf8]{inputenc}
   103   \usepackage{textcomp}
   104 
   105 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
   106 a Unicode character is treated as a single symbol, not a sequence of
   107 non-ASCII bytes as before.  Since Isabelle/ML string literals may
   108 contain symbols without further backslash escapes, Unicode can now be
   109 used here as well.  Recall that Symbol.explode in ML provides a
   110 consistent view on symbols, while raw explode (or String.explode)
   111 merely give a byte-oriented representation.
   112 
   113 * Theory loader: source files are primarily located via the master
   114 directory of each theory node (where the .thy file itself resides).
   115 The global load path is still partially available as legacy feature.
   116 Minor INCOMPATIBILITY due to subtle change in file lookup: use
   117 explicit paths, relatively to the theory.
   118 
   119 * Special treatment of ML file names has been discontinued.
   120 Historically, optional extensions .ML or .sml were added on demand --
   121 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
   122 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
   123 
   124 * Various options that affect pretty printing etc. are now properly
   125 handled within the context via configuration options, instead of
   126 unsynchronized references or print modes.  There are both ML Config.T
   127 entities and Isar declaration attributes to access these.
   128 
   129   ML (Config.T)                 Isar (attribute)
   130 
   131   eta_contract                  eta_contract
   132   show_brackets                 show_brackets
   133   show_sorts                    show_sorts
   134   show_types                    show_types
   135   show_question_marks           show_question_marks
   136   show_consts                   show_consts
   137   show_abbrevs                  show_abbrevs
   138 
   139   Syntax.ast_trace              syntax_ast_trace
   140   Syntax.ast_stat               syntax_ast_stat
   141   Syntax.ambiguity_level        syntax_ambiguity_level
   142 
   143   Goal_Display.goals_limit      goals_limit
   144   Goal_Display.show_main_goal   show_main_goal
   145 
   146   Method.rule_trace             rule_trace
   147 
   148   Thy_Output.display            thy_output_display
   149   Thy_Output.quotes             thy_output_quotes
   150   Thy_Output.indent             thy_output_indent
   151   Thy_Output.source             thy_output_source
   152   Thy_Output.break              thy_output_break
   153 
   154 Note that corresponding "..._default" references in ML may only be
   155 changed globally at the ROOT session setup, but *not* within a theory.
   156 The option "show_abbrevs" supersedes the former print mode
   157 "no_abbrevs" with inverted meaning.
   158 
   159 * More systematic naming of some configuration options.
   160 INCOMPATIBILITY.
   161 
   162   trace_simp  ~>  simp_trace
   163   debug_simp  ~>  simp_debug
   164 
   165 * Support for real valued configuration options, using simplistic
   166 floating-point notation that coincides with the inner syntax for
   167 float_token.
   168 
   169 * Support for real valued preferences (with approximative PGIP type):
   170 front-ends need to accept "pgint" values in float notation.
   171 INCOMPATIBILITY.
   172 
   173 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
   174 DejaVu Sans.
   175 
   176 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   177 
   178 
   179 *** Pure ***
   180 
   181 * Command 'type_synonym' (with single argument) replaces somewhat
   182 outdated 'types', which is still available as legacy feature for some
   183 time.
   184 
   185 * Command 'nonterminal' (with 'and' separated list of arguments)
   186 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
   187 
   188 * Command 'notepad' replaces former 'example_proof' for
   189 experimentation in Isar without any result.  INCOMPATIBILITY.
   190 
   191 * Locale interpretation commands 'interpret' and 'sublocale' accept
   192 lists of equations to map definitions in a locale to appropriate
   193 entities in the context of the interpretation.  The 'interpretation'
   194 command already provided this functionality.
   195 
   196 * Diagnostic command 'print_dependencies' prints the locale instances
   197 that would be activated if the specified expression was interpreted in
   198 the current context.  Variant "print_dependencies!" assumes a context
   199 without interpretations.
   200 
   201 * Diagnostic command 'print_interps' prints interpretations in proofs
   202 in addition to interpretations in theories.
   203 
   204 * Discontinued obsolete 'global' and 'local' commands to manipulate
   205 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
   206 Sign.root_path and Sign.local_path may be applied directly where this
   207 feature is still required for historical reasons.
   208 
   209 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
   210 'definition' instead.
   211 
   212 * The "prems" fact, which refers to the accidental collection of
   213 foundational premises in the context, is now explicitly marked as
   214 legacy feature and will be discontinued soon.  Consider using "assms"
   215 of the head statement or reference facts by explicit names.
   216 
   217 * Document antiquotations @{class} and @{type} print classes and type
   218 constructors.
   219 
   220 * Document antiquotation @{file} checks file/directory entries within
   221 the local file system.
   222 
   223 
   224 *** HOL ***
   225 
   226 * Coercive subtyping: functions can be declared as coercions and type
   227 inference will add them as necessary upon input of a term.  Theory
   228 Complex_Main declares real :: nat => real and real :: int => real as
   229 coercions. A coercion function f is declared like this:
   230 
   231   declare [[coercion f]]
   232 
   233 To lift coercions through type constructors (e.g. from nat => real to
   234 nat list => real list), map functions can be declared, e.g.
   235 
   236   declare [[coercion_map map]]
   237 
   238 Currently coercion inference is activated only in theories including
   239 real numbers, i.e. descendants of Complex_Main.  This is controlled by
   240 the configuration option "coercion_enabled", e.g. it can be enabled in
   241 other theories like this:
   242 
   243   declare [[coercion_enabled]]
   244 
   245 * Command 'partial_function' provides basic support for recursive
   246 function definitions over complete partial orders.  Concrete instances
   247 are provided for i) the option type, ii) tail recursion on arbitrary
   248 types, and iii) the heap monad of Imperative_HOL.  See
   249 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
   250 for examples.
   251 
   252 * Function package: f.psimps rules are no longer implicitly declared
   253 as [simp].  INCOMPATIBILITY.
   254 
   255 * Datatype package: theorems generated for executable equality (class
   256 "eq") carry proper names and are treated as default code equations.
   257 
   258 * Inductive package: now offers command 'inductive_simps' to
   259 automatically derive instantiated and simplified equations for
   260 inductive predicates, similar to 'inductive_cases'.
   261 
   262 * Command 'enriched_type' allows to register properties of the
   263 functorial structure of types.
   264 
   265 * Improved infrastructure for term evaluation using code generator
   266 techniques, in particular static evaluation conversions.
   267 
   268 * Code generator: Scala (2.8 or higher) has been added to the target
   269 languages.
   270 
   271 * Code generator: globbing constant expressions "*" and "Theory.*"
   272 have been replaced by the more idiomatic "_" and "Theory._".
   273 INCOMPATIBILITY.
   274 
   275 * Code generator: export_code without explicit file declaration prints
   276 to standard output.  INCOMPATIBILITY.
   277 
   278 * Code generator: do not print function definitions for case
   279 combinators any longer.
   280 
   281 * Code generator: simplification with rules determined with
   282 src/Tools/Code/code_simp.ML and method "code_simp".
   283 
   284 * Code generator for records: more idiomatic representation of record
   285 types.  Warning: records are not covered by ancient SML code
   286 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
   287 rep_datatype declaration helps to succeed then:
   288 
   289   record 'a foo = ...
   290   ...
   291   rep_datatype foo_ext ...
   292 
   293 * Records: logical foundation type for records does not carry a
   294 '_type' suffix any longer (obsolete due to authentic syntax).
   295 INCOMPATIBILITY.
   296 
   297 * Quickcheck now by default uses exhaustive testing instead of random
   298 testing.  Random testing can be invoked by "quickcheck [random]",
   299 exhaustive testing by "quickcheck [exhaustive]".
   300 
   301 * Quickcheck instantiates polymorphic types with small finite
   302 datatypes by default. This enables a simple execution mechanism to
   303 handle quantifiers and function equality over the finite datatypes.
   304 
   305 * Quickcheck random generator has been renamed from "code" to
   306 "random".  INCOMPATIBILITY.
   307 
   308 * Quickcheck now has a configurable time limit which is set to 30
   309 seconds by default. This can be changed by adding [timeout = n] to the
   310 quickcheck command. The time limit for Auto Quickcheck is still set
   311 independently.
   312 
   313 * Quickcheck in locales considers interpretations of that locale for
   314 counter example search.
   315 
   316 * Sledgehammer:
   317   - Added "smt" and "remote_smt" provers based on the "smt" proof
   318     method. See the Sledgehammer manual for details ("isabelle doc
   319     sledgehammer").
   320   - Renamed commands:
   321     sledgehammer atp_info ~> sledgehammer running_provers
   322     sledgehammer atp_kill ~> sledgehammer kill_provers
   323     sledgehammer available_atps ~> sledgehammer available_provers
   324     INCOMPATIBILITY.
   325   - Renamed options:
   326     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
   327     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
   328     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
   329     (and "ms" and "min" are no longer supported)
   330     INCOMPATIBILITY.
   331 
   332 * Nitpick:
   333   - Renamed options:
   334     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
   335     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
   336     INCOMPATIBILITY.
   337   - Added support for partial quotient types.
   338   - Added local versions of the "Nitpick.register_xxx" functions.
   339   - Added "whack" option.
   340   - Allow registration of quotient types as codatatypes.
   341   - Improved "merge_type_vars" option to merge more types.
   342   - Removed unsound "fast_descrs" option.
   343   - Added custom symmetry breaking for datatypes, making it possible to reach
   344     higher cardinalities.
   345   - Prevent the expansion of too large definitions.
   346 
   347 * Proof methods "metis" and "meson" now have configuration options
   348 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
   349 to diagnose these tools. E.g.
   350 
   351     using [[metis_trace = true]]
   352 
   353 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
   354 manually as command 'solve_direct'.
   355 
   356 * The default SMT solver Z3 must be enabled explicitly (due to
   357 licensing issues) by setting the environment variable
   358 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
   359 commercial applications, the SMT solver CVC3 is provided as fall-back;
   360 changing the SMT solver is done via the configuration option
   361 "smt_solver".
   362 
   363 * Remote SMT solvers need to be referred to by the "remote_" prefix,
   364 i.e. "remote_cvc3" and "remote_z3".
   365 
   366 * Added basic SMT support for datatypes, records, and typedefs using
   367 the oracle mode (no proofs).  Direct support of pairs has been dropped
   368 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
   369 support for a similar behavior).  Minor INCOMPATIBILITY.
   370 
   371 * Changed SMT configuration options:
   372   - Renamed:
   373     z3_proofs ~> smt_oracle (with inverted meaning)
   374     z3_trace_assms ~> smt_trace_used_facts
   375     INCOMPATIBILITY.
   376   - Added:
   377     smt_verbose
   378     smt_random_seed
   379     smt_datatypes
   380     smt_infer_triggers
   381     smt_monomorph_limit
   382     cvc3_options
   383     remote_cvc3_options
   384     remote_z3_options
   385     yices_options
   386 
   387 * Boogie output files (.b2i files) need to be declared in the theory
   388 header.
   389 
   390 * Simplification procedure "list_to_set_comprehension" rewrites list
   391 comprehensions applied to List.set to set comprehensions.  Occasional
   392 INCOMPATIBILITY, may be deactivated like this:
   393 
   394   declare [[simproc del: list_to_set_comprehension]]
   395 
   396 * Removed old version of primrec package.  INCOMPATIBILITY.
   397 
   398 * Removed simplifier congruence rule of "prod_case", as has for long
   399 been the case with "split".  INCOMPATIBILITY.
   400 
   401 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
   402 
   403 * Removed [split_format ... and ... and ...] version of
   404 [split_format].  Potential INCOMPATIBILITY.
   405 
   406 * Predicate "sorted" now defined inductively, with nice induction
   407 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
   408 
   409 * Constant "contents" renamed to "the_elem", to free the generic name
   410 contents for other uses.  INCOMPATIBILITY.
   411 
   412 * Renamed class eq and constant eq (for code generation) to class
   413 equal and constant equal, plus renaming of related facts and various
   414 tuning.  INCOMPATIBILITY.
   415 
   416 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
   417 
   418 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
   419 INCOMPATIBILITY.
   420 
   421 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
   422 avoid confusion with finite sets.  INCOMPATIBILITY.
   423 
   424 * Abandoned locales equiv, congruent and congruent2 for equivalence
   425 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
   426 for congruent(2)).
   427 
   428 * Some previously unqualified names have been qualified:
   429 
   430   types
   431     bool ~> HOL.bool
   432     nat ~> Nat.nat
   433 
   434   constants
   435     Trueprop ~> HOL.Trueprop
   436     True ~> HOL.True
   437     False ~> HOL.False
   438     op & ~> HOL.conj
   439     op | ~> HOL.disj
   440     op --> ~> HOL.implies
   441     op = ~> HOL.eq
   442     Not ~> HOL.Not
   443     The ~> HOL.The
   444     All ~> HOL.All
   445     Ex ~> HOL.Ex
   446     Ex1 ~> HOL.Ex1
   447     Let ~> HOL.Let
   448     If ~> HOL.If
   449     Ball ~> Set.Ball
   450     Bex ~> Set.Bex
   451     Suc ~> Nat.Suc
   452     Pair ~> Product_Type.Pair
   453     fst ~> Product_Type.fst
   454     snd ~> Product_Type.snd
   455     curry ~> Product_Type.curry
   456     op : ~> Set.member
   457     Collect ~> Set.Collect
   458 
   459 INCOMPATIBILITY.
   460 
   461 * More canonical naming convention for some fundamental definitions:
   462 
   463     bot_bool_eq ~> bot_bool_def
   464     top_bool_eq ~> top_bool_def
   465     inf_bool_eq ~> inf_bool_def
   466     sup_bool_eq ~> sup_bool_def
   467     bot_fun_eq  ~> bot_fun_def
   468     top_fun_eq  ~> top_fun_def
   469     inf_fun_eq  ~> inf_fun_def
   470     sup_fun_eq  ~> sup_fun_def
   471 
   472 INCOMPATIBILITY.
   473 
   474 * More stylized fact names:
   475 
   476   expand_fun_eq ~> fun_eq_iff
   477   expand_set_eq ~> set_eq_iff
   478   set_ext       ~> set_eqI
   479   nat_number    ~> eval_nat_numeral
   480 
   481 INCOMPATIBILITY.
   482 
   483 * Refactoring of code-generation specific operations in theory List:
   484 
   485   constants
   486     null ~> List.null
   487 
   488   facts
   489     mem_iff ~> member_def
   490     null_empty ~> null_def
   491 
   492 INCOMPATIBILITY.  Note that these were not supposed to be used
   493 regularly unless for striking reasons; their main purpose was code
   494 generation.
   495 
   496 Various operations from the Haskell prelude are used for generating
   497 Haskell code.
   498 
   499 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
   500 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
   501 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
   502 
   503 * Abolished some non-alphabetic type names: "prod" and "sum" replace
   504 "*" and "+" respectively.  INCOMPATIBILITY.
   505 
   506 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
   507 "Sum_Type.Plus" instead.
   508 
   509 * Constant "split" has been merged with constant "prod_case"; names of
   510 ML functions, facts etc. involving split have been retained so far,
   511 though.  INCOMPATIBILITY.
   512 
   513 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
   514 instead.  INCOMPATIBILITY.
   515 
   516 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
   517 INCOMPATIBILITY.
   518 
   519 * Former theory Library/Enum is now part of the HOL-Main image.
   520 INCOMPATIBILITY: all constants of the Enum theory now have to be
   521 referred to by its qualified name.
   522 
   523   enum    ~>  Enum.enum
   524   nlists  ~>  Enum.nlists
   525   product ~>  Enum.product
   526 
   527 * Theory Library/Monad_Syntax provides do-syntax for monad types.
   528 Syntax in Library/State_Monad has been changed to avoid ambiguities.
   529 INCOMPATIBILITY.
   530 
   531 * Theory Library/SetsAndFunctions has been split into
   532 Library/Function_Algebras and Library/Set_Algebras; canonical names
   533 for instance definitions for functions; various improvements.
   534 INCOMPATIBILITY.
   535 
   536 * Theory Library/Multiset provides stable quicksort implementation of
   537 sort_key.
   538 
   539 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
   540 INCOMPATIBILITY.
   541 
   542 * Session Multivariate_Analysis: introduced a type class for euclidean
   543 space.  Most theorems are now stated in terms of euclidean spaces
   544 instead of finite cartesian products.
   545 
   546   types
   547     real ^ 'n ~>  'a::real_vector
   548               ~>  'a::euclidean_space
   549               ~>  'a::ordered_euclidean_space
   550         (depends on your needs)
   551 
   552   constants
   553      _ $ _        ~> _ $$ _
   554      \<chi> x. _  ~> \<chi>\<chi> x. _
   555      CARD('n)     ~> DIM('a)
   556 
   557 Also note that the indices are now natural numbers and not from some
   558 finite type. Finite cartesian products of euclidean spaces, products
   559 of euclidean spaces the real and complex numbers are instantiated to
   560 be euclidean_spaces.  INCOMPATIBILITY.
   561 
   562 * Session Probability: introduced pextreal as positive extended real
   563 numbers.  Use pextreal as value for measures.  Introduce the
   564 Radon-Nikodym derivative, product spaces and Fubini's theorem for
   565 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
   566 the integral in Multivariate Analysis.  INCOMPATIBILITY.
   567 
   568 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   569 INCOMPATIBILITY.
   570 
   571 * Session SPARK (with image HOL-SPARK) provides commands to load and
   572 prove verification conditions generated by the SPARK Ada program
   573 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
   574 
   575 
   576 *** HOL-Algebra ***
   577 
   578 * Theorems for additive ring operations (locale abelian_monoid and
   579 descendants) are generated by interpretation from their multiplicative
   580 counterparts.  Names (in particular theorem names) have the mandatory
   581 qualifier 'add'.  Previous theorem names are redeclared for
   582 compatibility.
   583 
   584 * Structure "int_ring" is now an abbreviation (previously a
   585 definition).  This fits more natural with advanced interpretations.
   586 
   587 
   588 *** HOLCF ***
   589 
   590 * The domain package now runs in definitional mode by default: The
   591 former command 'new_domain' is now called 'domain'.  To use the domain
   592 package in its original axiomatic mode, use 'domain (unsafe)'.
   593 INCOMPATIBILITY.
   594 
   595 * The new class "domain" is now the default sort.  Class "predomain"
   596 is an unpointed version of "domain". Theories can be updated by
   597 replacing sort annotations as shown below.  INCOMPATIBILITY.
   598 
   599   'a::type ~> 'a::countable
   600   'a::cpo  ~> 'a::predomain
   601   'a::pcpo ~> 'a::domain
   602 
   603 * The old type class "rep" has been superseded by class "domain".
   604 Accordingly, users of the definitional package must remove any
   605 "default_sort rep" declarations.  INCOMPATIBILITY.
   606 
   607 * The domain package (definitional mode) now supports unpointed
   608 predomain argument types, as long as they are marked 'lazy'. (Strict
   609 arguments must be in class "domain".) For example, the following
   610 domain definition now works:
   611 
   612   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
   613 
   614 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
   615 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
   616 'a option, and 'a list.  Additionally, it configures fixrec and the
   617 domain package to work with these types.  For example:
   618 
   619   fixrec isInl :: "('a + 'b) u -> tr"
   620     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
   621 
   622   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
   623 
   624 * The "(permissive)" option of fixrec has been replaced with a
   625 per-equation "(unchecked)" option. See
   626 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
   627 
   628 * The "bifinite" class no longer fixes a constant "approx"; the class
   629 now just asserts that such a function exists.  INCOMPATIBILITY.
   630 
   631 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
   632 defines an embedding of type 'a defl into udom by default; instances
   633 of "bifinite" and "domain" classes are available in
   634 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
   635 
   636 * The syntax "REP('a)" has been replaced with "DEFL('a)".
   637 
   638 * The predicate "directed" has been removed.  INCOMPATIBILITY.
   639 
   640 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
   641 
   642 * The function "cprod_map" has been renamed to "prod_map".
   643 INCOMPATIBILITY.
   644 
   645 * The monadic bind operator on each powerdomain has new binder syntax
   646 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
   647 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
   648 
   649 * The infix syntax for binary union on each powerdomain has changed
   650 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
   651 syntax.  INCOMPATIBILITY.
   652 
   653 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
   654 still supported as an input translation.
   655 
   656 * Renamed some theorems (the original names are also still available).
   657 
   658   expand_fun_below   ~> fun_below_iff
   659   below_fun_ext      ~> fun_belowI
   660   expand_cfun_eq     ~> cfun_eq_iff
   661   ext_cfun           ~> cfun_eqI
   662   expand_cfun_below  ~> cfun_below_iff
   663   below_cfun_ext     ~> cfun_belowI
   664   cont2cont_Rep_CFun ~> cont2cont_APP
   665 
   666 * The Abs and Rep functions for various types have changed names.
   667 Related theorem names have also changed to match. INCOMPATIBILITY.
   668 
   669   Rep_CFun  ~> Rep_cfun
   670   Abs_CFun  ~> Abs_cfun
   671   Rep_Sprod ~> Rep_sprod
   672   Abs_Sprod ~> Abs_sprod
   673   Rep_Ssum  ~> Rep_ssum
   674   Abs_Ssum  ~> Abs_ssum
   675 
   676 * Lemmas with names of the form *_defined_iff or *_strict_iff have
   677 been renamed to *_bottom_iff.  INCOMPATIBILITY.
   678 
   679 * Various changes to bisimulation/coinduction with domain package:
   680 
   681   - Definitions of "bisim" constants no longer mention definedness.
   682   - With mutual recursion, "bisim" predicate is now curried.
   683   - With mutual recursion, each type gets a separate coind theorem.
   684   - Variable names in bisim_def and coinduct rules have changed.
   685 
   686 INCOMPATIBILITY.
   687 
   688 * Case combinators generated by the domain package for type "foo" are
   689 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
   690 
   691 * Several theorems have been renamed to more accurately reflect the
   692 names of constants and types involved.  INCOMPATIBILITY.
   693 
   694   thelub_const    ~> lub_const
   695   lub_const       ~> is_lub_const
   696   thelubI         ~> lub_eqI
   697   is_lub_lub      ~> is_lubD2
   698   lubI            ~> is_lub_lub
   699   unique_lub      ~> is_lub_unique
   700   is_ub_lub       ~> is_lub_rangeD1
   701   lub_bin_chain   ~> is_lub_bin_chain
   702   lub_fun         ~> is_lub_fun
   703   thelub_fun      ~> lub_fun
   704   thelub_cfun     ~> lub_cfun
   705   thelub_Pair     ~> lub_Pair
   706   lub_cprod       ~> is_lub_prod
   707   thelub_cprod    ~> lub_prod
   708   minimal_cprod   ~> minimal_prod
   709   inst_cprod_pcpo ~> inst_prod_pcpo
   710   UU_I            ~> bottomI
   711   compact_UU      ~> compact_bottom
   712   deflation_UU    ~> deflation_bottom
   713   finite_deflation_UU ~> finite_deflation_bottom
   714 
   715 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
   716 
   717   sq_ord_less_eq_trans ~> below_eq_trans
   718   sq_ord_eq_less_trans ~> eq_below_trans
   719   refl_less            ~> below_refl
   720   trans_less           ~> below_trans
   721   antisym_less         ~> below_antisym
   722   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
   723   box_less             ~> box_below
   724   rev_trans_less       ~> rev_below_trans
   725   not_less2not_eq      ~> not_below2not_eq
   726   less_UU_iff          ~> below_UU_iff
   727   flat_less_iff        ~> flat_below_iff
   728   adm_less             ~> adm_below
   729   adm_not_less         ~> adm_not_below
   730   adm_compact_not_less ~> adm_compact_not_below
   731   less_fun_def         ~> below_fun_def
   732   expand_fun_less      ~> fun_below_iff
   733   less_fun_ext         ~> fun_belowI
   734   less_discr_def       ~> below_discr_def
   735   discr_less_eq        ~> discr_below_eq
   736   less_unit_def        ~> below_unit_def
   737   less_cprod_def       ~> below_prod_def
   738   prod_lessI           ~> prod_belowI
   739   Pair_less_iff        ~> Pair_below_iff
   740   fst_less_iff         ~> fst_below_iff
   741   snd_less_iff         ~> snd_below_iff
   742   expand_cfun_less     ~> cfun_below_iff
   743   less_cfun_ext        ~> cfun_belowI
   744   injection_less       ~> injection_below
   745   less_up_def          ~> below_up_def
   746   not_Iup_less         ~> not_Iup_below
   747   Iup_less             ~> Iup_below
   748   up_less              ~> up_below
   749   Def_inject_less_eq   ~> Def_below_Def
   750   Def_less_is_eq       ~> Def_below_iff
   751   spair_less_iff       ~> spair_below_iff
   752   less_sprod           ~> below_sprod
   753   spair_less           ~> spair_below
   754   sfst_less_iff        ~> sfst_below_iff
   755   ssnd_less_iff        ~> ssnd_below_iff
   756   fix_least_less       ~> fix_least_below
   757   dist_less_one        ~> dist_below_one
   758   less_ONE             ~> below_ONE
   759   ONE_less_iff         ~> ONE_below_iff
   760   less_sinlD           ~> below_sinlD
   761   less_sinrD           ~> below_sinrD
   762 
   763 
   764 *** FOL and ZF ***
   765 
   766 * All constant names are now qualified internally and use proper
   767 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
   768 
   769 
   770 *** ML ***
   771 
   772 * Antiquotation @{assert} inlines a function bool -> unit that raises
   773 Fail if the argument is false.  Due to inlining the source position of
   774 failed assertions is included in the error output.
   775 
   776 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
   777 text is in practice always evaluated with a stable theory checkpoint.
   778 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
   779 
   780 * Antiquotation @{theory A} refers to theory A from the ancestry of
   781 the current context, not any accidental theory loader state as before.
   782 Potential INCOMPATIBILITY, subtle change in semantics.
   783 
   784 * Syntax.pretty_priority (default 0) configures the required priority
   785 of pretty-printed output and thus affects insertion of parentheses.
   786 
   787 * Syntax.default_root (default "any") configures the inner syntax
   788 category (nonterminal symbol) for parsing of terms.
   789 
   790 * Former exception Library.UnequalLengths now coincides with
   791 ListPair.UnequalLengths.
   792 
   793 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
   794 main functionality is provided by structure Simplifier.
   795 
   796 * Renamed raw "explode" function to "raw_explode" to emphasize its
   797 meaning.  Note that internally to Isabelle, Symbol.explode is used in
   798 almost all situations.
   799 
   800 * Discontinued obsolete function sys_error and exception SYS_ERROR.
   801 See implementation manual for further details on exceptions in
   802 Isabelle/ML.
   803 
   804 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
   805 meaning.
   806 
   807 * Renamed structure PureThy to Pure_Thy and moved most of its
   808 operations to structure Global_Theory, to emphasize that this is
   809 rarely-used global-only stuff.
   810 
   811 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
   812 instead (or tracing for high-volume output).
   813 
   814 * Configuration option show_question_marks only affects regular pretty
   815 printing of types and terms, not raw Term.string_of_vname.
   816 
   817 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
   818 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
   819 @{thms} for most purposes.
   820 
   821 * ML structure Unsynchronized is never opened, not even in Isar
   822 interaction mode as before.  Old Unsynchronized.set etc. have been
   823 discontinued -- use plain := instead.  This should be *rare* anyway,
   824 since modern tools always work via official context data, notably
   825 configuration options.
   826 
   827 * Parallel and asynchronous execution requires special care concerning
   828 interrupts.  Structure Exn provides some convenience functions that
   829 avoid working directly with raw Interrupt.  User code must not absorb
   830 interrupts -- intermediate handling (for cleanup etc.) needs to be
   831 followed by re-raising of the original exception.  Another common
   832 source of mistakes are "handle _" patterns, which make the meaning of
   833 the program subject to physical effects of the environment.
   834 
   835 
   836 
   837 New in Isabelle2009-2 (June 2010)
   838 ---------------------------------
   839 
   840 *** General ***
   841 
   842 * Authentic syntax for *all* logical entities (type classes, type
   843 constructors, term constants): provides simple and robust
   844 correspondence between formal entities and concrete syntax.  Within
   845 the parse tree / AST representations, "constants" are decorated by
   846 their category (class, type, const) and spelled out explicitly with
   847 their full internal name.
   848 
   849 Substantial INCOMPATIBILITY concerning low-level syntax declarations
   850 and translations (translation rules and translation functions in ML).
   851 Some hints on upgrading:
   852 
   853   - Many existing uses of 'syntax' and 'translations' can be replaced
   854     by more modern 'type_notation', 'notation' and 'abbreviation',
   855     which are independent of this issue.
   856 
   857   - 'translations' require markup within the AST; the term syntax
   858     provides the following special forms:
   859 
   860       CONST c   -- produces syntax version of constant c from context
   861       XCONST c  -- literally c, checked as constant from context
   862       c         -- literally c, if declared by 'syntax'
   863 
   864     Plain identifiers are treated as AST variables -- occasionally the
   865     system indicates accidental variables via the error "rhs contains
   866     extra variables".
   867 
   868     Type classes and type constructors are marked according to their
   869     concrete syntax.  Some old translations rules need to be written
   870     for the "type" category, using type constructor application
   871     instead of pseudo-term application of the default category
   872     "logic".
   873 
   874   - 'parse_translation' etc. in ML may use the following
   875     antiquotations:
   876 
   877       @{class_syntax c}   -- type class c within parse tree / AST
   878       @{term_syntax c}    -- type constructor c within parse tree / AST
   879       @{const_syntax c}   -- ML version of "CONST c" above
   880       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
   881 
   882   - Literal types within 'typed_print_translations', i.e. those *not*
   883     represented as pseudo-terms are represented verbatim.  Use @{class
   884     c} or @{type_name c} here instead of the above syntax
   885     antiquotations.
   886 
   887 Note that old non-authentic syntax was based on unqualified base
   888 names, so all of the above "constant" names would coincide.  Recall
   889 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
   890 diagnose syntax problems.
   891 
   892 * Type constructors admit general mixfix syntax, not just infix.
   893 
   894 * Concrete syntax may be attached to local entities without a proof
   895 body, too.  This works via regular mixfix annotations for 'fix',
   896 'def', 'obtain' etc. or via the explicit 'write' command, which is
   897 similar to the 'notation' command in theory specifications.
   898 
   899 * Discontinued unnamed infix syntax (legacy feature for many years) --
   900 need to specify constant name and syntax separately.  Internal ML
   901 datatype constructors have been renamed from InfixName to Infix etc.
   902 Minor INCOMPATIBILITY.
   903 
   904 * Schematic theorem statements need to be explicitly markup as such,
   905 via commands 'schematic_lemma', 'schematic_theorem',
   906 'schematic_corollary'.  Thus the relevance of the proof is made
   907 syntactically clear, which impacts performance in a parallel or
   908 asynchronous interactive environment.  Minor INCOMPATIBILITY.
   909 
   910 * Use of cumulative prems via "!" in some proof methods has been
   911 discontinued (old legacy feature).
   912 
   913 * References 'trace_simp' and 'debug_simp' have been replaced by
   914 configuration options stored in the context. Enabling tracing (the
   915 case of debugging is similar) in proofs works via
   916 
   917   using [[trace_simp = true]]
   918 
   919 Tracing is then active for all invocations of the simplifier in
   920 subsequent goal refinement steps. Tracing may also still be enabled or
   921 disabled via the ProofGeneral settings menu.
   922 
   923 * Separate commands 'hide_class', 'hide_type', 'hide_const',
   924 'hide_fact' replace the former 'hide' KIND command.  Minor
   925 INCOMPATIBILITY.
   926 
   927 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
   928 more efficient than combinations with -q1 or -q2.
   929 
   930 
   931 *** Pure ***
   932 
   933 * Proofterms record type-class reasoning explicitly, using the
   934 "unconstrain" operation internally.  This eliminates all sort
   935 constraints from a theorem and proof, introducing explicit
   936 OFCLASS-premises.  On the proof term level, this operation is
   937 automatically applied at theorem boundaries, such that closed proofs
   938 are always free of sort constraints.  INCOMPATIBILITY for tools that
   939 inspect proof terms.
   940 
   941 * Local theory specifications may depend on extra type variables that
   942 are not present in the result type -- arguments TYPE('a) :: 'a itself
   943 are added internally.  For example:
   944 
   945   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
   946 
   947 * Predicates of locales introduced by classes carry a mandatory
   948 "class" prefix.  INCOMPATIBILITY.
   949 
   950 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
   951 
   952 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
   953 'class' instead.
   954 
   955 * Command 'code_reflect' allows to incorporate generated ML code into
   956 runtime environment; replaces immature code_datatype antiquotation.
   957 INCOMPATIBILITY.
   958 
   959 * Code generator: simple concept for abstract datatypes obeying
   960 invariants.
   961 
   962 * Code generator: details of internal data cache have no impact on the
   963 user space functionality any longer.
   964 
   965 * Methods "unfold_locales" and "intro_locales" ignore non-locale
   966 subgoals.  This is more appropriate for interpretations with 'where'.
   967 INCOMPATIBILITY.
   968 
   969 * Command 'example_proof' opens an empty proof body.  This allows to
   970 experiment with Isar, without producing any persistent result.
   971 
   972 * Commands 'type_notation' and 'no_type_notation' declare type syntax
   973 within a local theory context, with explicit checking of the
   974 constructors involved (in contrast to the raw 'syntax' versions).
   975 
   976 * Commands 'types' and 'typedecl' now work within a local theory
   977 context -- without introducing dependencies on parameters or
   978 assumptions, which is not possible in Isabelle/Pure.
   979 
   980 * Command 'defaultsort' has been renamed to 'default_sort', it works
   981 within a local theory context.  Minor INCOMPATIBILITY.
   982 
   983 
   984 *** HOL ***
   985 
   986 * Command 'typedef' now works within a local theory context -- without
   987 introducing dependencies on parameters or assumptions, which is not
   988 possible in Isabelle/Pure/HOL.  Note that the logical environment may
   989 contain multiple interpretations of local typedefs (with different
   990 non-emptiness proofs), even in a global theory context.
   991 
   992 * New package for quotient types.  Commands 'quotient_type' and
   993 'quotient_definition' may be used for defining types and constants by
   994 quotient constructions.  An example is the type of integers created by
   995 quotienting pairs of natural numbers:
   996 
   997   fun
   998     intrel :: "(nat * nat) => (nat * nat) => bool"
   999   where
  1000     "intrel (x, y) (u, v) = (x + v = u + y)"
  1001 
  1002   quotient_type int = "nat * nat" / intrel
  1003     by (auto simp add: equivp_def expand_fun_eq)
  1004 
  1005   quotient_definition
  1006     "0::int" is "(0::nat, 0::nat)"
  1007 
  1008 The method "lifting" can be used to lift of theorems from the
  1009 underlying "raw" type to the quotient type.  The example
  1010 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  1011 construction and provides a reasoning infrastructure for finite sets.
  1012 
  1013 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  1014 clash with new theory Quotient in Main HOL.
  1015 
  1016 * Moved the SMT binding into the main HOL session, eliminating
  1017 separate HOL-SMT session.
  1018 
  1019 * List membership infix mem operation is only an input abbreviation.
  1020 INCOMPATIBILITY.
  1021 
  1022 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  1023 for future developements; former Library/Word.thy is still present in
  1024 the AFP entry RSAPPS.
  1025 
  1026 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  1027 longer shadowed.  INCOMPATIBILITY.
  1028 
  1029 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  1030 INCOMPATIBILITY.
  1031 
  1032 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  1033 INCOMPATIBILITY.
  1034 
  1035 * Dropped normalizing_semiring etc; use the facts in semiring classes
  1036 instead.  INCOMPATIBILITY.
  1037 
  1038 * Dropped several real-specific versions of lemmas about floor and
  1039 ceiling; use the generic lemmas from theory "Archimedean_Field"
  1040 instead.  INCOMPATIBILITY.
  1041 
  1042   floor_number_of_eq         ~> floor_number_of
  1043   le_floor_eq_number_of      ~> number_of_le_floor
  1044   le_floor_eq_zero           ~> zero_le_floor
  1045   le_floor_eq_one            ~> one_le_floor
  1046   floor_less_eq_number_of    ~> floor_less_number_of
  1047   floor_less_eq_zero         ~> floor_less_zero
  1048   floor_less_eq_one          ~> floor_less_one
  1049   less_floor_eq_number_of    ~> number_of_less_floor
  1050   less_floor_eq_zero         ~> zero_less_floor
  1051   less_floor_eq_one          ~> one_less_floor
  1052   floor_le_eq_number_of      ~> floor_le_number_of
  1053   floor_le_eq_zero           ~> floor_le_zero
  1054   floor_le_eq_one            ~> floor_le_one
  1055   floor_subtract_number_of   ~> floor_diff_number_of
  1056   floor_subtract_one         ~> floor_diff_one
  1057   ceiling_number_of_eq       ~> ceiling_number_of
  1058   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  1059   ceiling_le_zero_eq         ~> ceiling_le_zero
  1060   ceiling_le_eq_one          ~> ceiling_le_one
  1061   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  1062   less_ceiling_eq_zero       ~> zero_less_ceiling
  1063   less_ceiling_eq_one        ~> one_less_ceiling
  1064   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  1065   ceiling_less_eq_zero       ~> ceiling_less_zero
  1066   ceiling_less_eq_one        ~> ceiling_less_one
  1067   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  1068   le_ceiling_eq_zero         ~> zero_le_ceiling
  1069   le_ceiling_eq_one          ~> one_le_ceiling
  1070   ceiling_subtract_number_of ~> ceiling_diff_number_of
  1071   ceiling_subtract_one       ~> ceiling_diff_one
  1072 
  1073 * Theory "Finite_Set": various folding_XXX locales facilitate the
  1074 application of the various fold combinators on finite sets.
  1075 
  1076 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  1077 provides abstract red-black tree type which is backed by "RBT_Impl" as
  1078 implementation.  INCOMPATIBILTY.
  1079 
  1080 * Theory Library/Coinductive_List has been removed -- superseded by
  1081 AFP/thys/Coinductive.
  1082 
  1083 * Theory PReal, including the type "preal" and related operations, has
  1084 been removed.  INCOMPATIBILITY.
  1085 
  1086 * Real: new development using Cauchy Sequences.
  1087 
  1088 * Split off theory "Big_Operators" containing setsum, setprod,
  1089 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  1090 
  1091 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  1092 "Int" etc.  INCOMPATIBILITY.
  1093 
  1094 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  1095 
  1096 * New set of rules "ac_simps" provides combined assoc / commute
  1097 rewrites for all interpretations of the appropriate generic locales.
  1098 
  1099 * Renamed theory "OrderedGroup" to "Groups" and split theory
  1100 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  1101 appropriate and more consistent names suitable for name prefixes
  1102 within the HOL theories.  INCOMPATIBILITY.
  1103 
  1104 * Some generic constants have been put to appropriate theories:
  1105   - less_eq, less: Orderings
  1106   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  1107   - inverse, divide: Rings
  1108 INCOMPATIBILITY.
  1109 
  1110 * More consistent naming of type classes involving orderings (and
  1111 lattices):
  1112 
  1113     lower_semilattice                   ~> semilattice_inf
  1114     upper_semilattice                   ~> semilattice_sup
  1115 
  1116     dense_linear_order                  ~> dense_linorder
  1117 
  1118     pordered_ab_group_add               ~> ordered_ab_group_add
  1119     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  1120     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  1121     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  1122     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  1123     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  1124     pordered_cancel_semiring            ~> ordered_cancel_semiring
  1125     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  1126     pordered_comm_ring                  ~> ordered_comm_ring
  1127     pordered_comm_semiring              ~> ordered_comm_semiring
  1128     pordered_ring                       ~> ordered_ring
  1129     pordered_ring_abs                   ~> ordered_ring_abs
  1130     pordered_semiring                   ~> ordered_semiring
  1131 
  1132     ordered_ab_group_add                ~> linordered_ab_group_add
  1133     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  1134     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  1135     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  1136     ordered_field                       ~> linordered_field
  1137     ordered_field_no_lb                 ~> linordered_field_no_lb
  1138     ordered_field_no_ub                 ~> linordered_field_no_ub
  1139     ordered_field_dense_linear_order    ~> dense_linordered_field
  1140     ordered_idom                        ~> linordered_idom
  1141     ordered_ring                        ~> linordered_ring
  1142     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  1143     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  1144     ordered_ring_strict                 ~> linordered_ring_strict
  1145     ordered_semidom                     ~> linordered_semidom
  1146     ordered_semiring                    ~> linordered_semiring
  1147     ordered_semiring_1                  ~> linordered_semiring_1
  1148     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  1149     ordered_semiring_strict             ~> linordered_semiring_strict
  1150 
  1151   The following slightly odd type classes have been moved to a
  1152   separate theory Library/Lattice_Algebras:
  1153 
  1154     lordered_ab_group_add               ~> lattice_ab_group_add
  1155     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  1156     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  1157     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  1158     lordered_ring                       ~> lattice_ring
  1159 
  1160 INCOMPATIBILITY.
  1161 
  1162 * Refined field classes:
  1163   - classes division_ring_inverse_zero, field_inverse_zero,
  1164     linordered_field_inverse_zero include rule inverse 0 = 0 --
  1165     subsumes former division_by_zero class;
  1166   - numerous lemmas have been ported from field to division_ring.
  1167 INCOMPATIBILITY.
  1168 
  1169 * Refined algebra theorem collections:
  1170   - dropped theorem group group_simps, use algebra_simps instead;
  1171   - dropped theorem group ring_simps, use field_simps instead;
  1172   - proper theorem collection field_simps subsumes former theorem
  1173     groups field_eq_simps and field_simps;
  1174   - dropped lemma eq_minus_self_iff which is a duplicate for
  1175     equal_neg_zero.
  1176 INCOMPATIBILITY.
  1177 
  1178 * Theory Finite_Set and List: some lemmas have been generalized from
  1179 sets to lattices:
  1180 
  1181   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  1182   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  1183   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  1184   union_Union_fold_union        ~> sup_Sup_fold_sup
  1185   Inter_fold_inter              ~> Inf_fold_inf
  1186   Union_fold_union              ~> Sup_fold_sup
  1187   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  1188   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  1189   INTER_fold_inter              ~> INFI_fold_inf
  1190   UNION_fold_union              ~> SUPR_fold_sup
  1191 
  1192 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  1193 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  1194 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  1195 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  1196 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  1197 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  1198 
  1199 * Reorganized theory Multiset: swapped notation of pointwise and
  1200 multiset order:
  1201 
  1202   - pointwise ordering is instance of class order with standard syntax
  1203     <= and <;
  1204   - multiset ordering has syntax <=# and <#; partial order properties
  1205     are provided by means of interpretation with prefix
  1206     multiset_order;
  1207   - less duplication, less historical organization of sections,
  1208     conversion from associations lists to multisets, rudimentary code
  1209     generation;
  1210   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  1211     if needed.
  1212 
  1213 Renamed:
  1214 
  1215   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  1216   multi_count_ext  ~>  multiset_ext
  1217   diff_union_inverse2  ~>  diff_union_cancelR
  1218 
  1219 INCOMPATIBILITY.
  1220 
  1221 * Theory Permutation: replaced local "remove" by List.remove1.
  1222 
  1223 * Code generation: ML and OCaml code is decorated with signatures.
  1224 
  1225 * Theory List: added transpose.
  1226 
  1227 * Library/Nat_Bijection.thy is a collection of bijective functions
  1228 between nat and other types, which supersedes the older libraries
  1229 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  1230 
  1231   Constants:
  1232   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  1233   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  1234   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  1235   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  1236   Countable.pair_encode           ~> prod_encode
  1237   NatIso.prod2nat                 ~> prod_encode
  1238   NatIso.nat2prod                 ~> prod_decode
  1239   NatIso.sum2nat                  ~> sum_encode
  1240   NatIso.nat2sum                  ~> sum_decode
  1241   NatIso.list2nat                 ~> list_encode
  1242   NatIso.nat2list                 ~> list_decode
  1243   NatIso.set2nat                  ~> set_encode
  1244   NatIso.nat2set                  ~> set_decode
  1245 
  1246   Lemmas:
  1247   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  1248   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  1249   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  1250   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  1251   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  1252   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  1253   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  1254   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  1255   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  1256   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  1257   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  1258   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  1259   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  1260 
  1261 * Sledgehammer:
  1262   - Renamed ATP commands:
  1263     atp_info     ~> sledgehammer running_atps
  1264     atp_kill     ~> sledgehammer kill_atps
  1265     atp_messages ~> sledgehammer messages
  1266     atp_minimize ~> sledgehammer minimize
  1267     print_atps   ~> sledgehammer available_atps
  1268     INCOMPATIBILITY.
  1269   - Added user's manual ("isabelle doc sledgehammer").
  1270   - Added option syntax and "sledgehammer_params" to customize
  1271     Sledgehammer's behavior.  See the manual for details.
  1272   - Modified the Isar proof reconstruction code so that it produces
  1273     direct proofs rather than proofs by contradiction.  (This feature
  1274     is still experimental.)
  1275   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  1276     full-typed mode.
  1277   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  1278 
  1279 * Nitpick:
  1280   - Added and implemented "binary_ints" and "bits" options.
  1281   - Added "std" option and implemented support for nonstandard models.
  1282   - Added and implemented "finitize" option to improve the precision
  1283     of infinite datatypes based on a monotonicity analysis.
  1284   - Added support for quotient types.
  1285   - Added support for "specification" and "ax_specification"
  1286     constructs.
  1287   - Added support for local definitions (for "function" and
  1288     "termination" proofs).
  1289   - Added support for term postprocessors.
  1290   - Optimized "Multiset.multiset" and "FinFun.finfun".
  1291   - Improved efficiency of "destroy_constrs" optimization.
  1292   - Fixed soundness bugs related to "destroy_constrs" optimization and
  1293     record getters.
  1294   - Fixed soundness bug related to higher-order constructors.
  1295   - Fixed soundness bug when "full_descrs" is enabled.
  1296   - Improved precision of set constructs.
  1297   - Added "atoms" option.
  1298   - Added cache to speed up repeated Kodkod invocations on the same
  1299     problems.
  1300   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  1301     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  1302     "SAT4J_Light".  INCOMPATIBILITY.
  1303   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  1304     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  1305   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  1306 
  1307 * Method "induct" now takes instantiations of the form t, where t is not
  1308   a variable, as a shorthand for "x == t", where x is a fresh variable.
  1309   If this is not intended, t has to be enclosed in parentheses.
  1310   By default, the equalities generated by definitional instantiations
  1311   are pre-simplified, which may cause parameters of inductive cases
  1312   to disappear, or may even delete some of the inductive cases.
  1313   Use "induct (no_simp)" instead of "induct" to restore the old
  1314   behaviour. The (no_simp) option is also understood by the "cases"
  1315   and "nominal_induct" methods, which now perform pre-simplification, too.
  1316   INCOMPATIBILITY.
  1317 
  1318 
  1319 *** HOLCF ***
  1320 
  1321 * Variable names in lemmas generated by the domain package have
  1322 changed; the naming scheme is now consistent with the HOL datatype
  1323 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  1324 
  1325 * The domain package no longer defines the function "foo_copy" for
  1326 recursive domain "foo".  The reach lemma is now stated directly in
  1327 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  1328 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  1329 
  1330 * Most definedness lemmas generated by the domain package (previously
  1331 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  1332 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  1333 Proofs that used definedness lemmas as intro rules may break,
  1334 potential INCOMPATIBILITY.
  1335 
  1336 * Induction and casedist rules generated by the domain package now
  1337 declare proper case_names (one called "bottom", and one named for each
  1338 constructor).  INCOMPATIBILITY.
  1339 
  1340 * For mutually-recursive domains, separate "reach" and "take_lemma"
  1341 rules are generated for each domain, INCOMPATIBILITY.
  1342 
  1343   foo_bar.reach       ~> foo.reach  bar.reach
  1344   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  1345 
  1346 * Some lemmas generated by the domain package have been renamed for
  1347 consistency with the datatype package, INCOMPATIBILITY.
  1348 
  1349   foo.ind        ~> foo.induct
  1350   foo.finite_ind ~> foo.finite_induct
  1351   foo.coind      ~> foo.coinduct
  1352   foo.casedist   ~> foo.exhaust
  1353   foo.exhaust    ~> foo.nchotomy
  1354 
  1355 * For consistency with other definition packages, the fixrec package
  1356 now generates qualified theorem names, INCOMPATIBILITY.
  1357 
  1358   foo_simps  ~> foo.simps
  1359   foo_unfold ~> foo.unfold
  1360   foo_induct ~> foo.induct
  1361 
  1362 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  1363 method and internal fixrec proofs now use the default simpset instead.
  1364 INCOMPATIBILITY.
  1365 
  1366 * The "contlub" predicate has been removed.  Proof scripts should use
  1367 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  1368 
  1369 * The "admw" predicate has been removed, INCOMPATIBILITY.
  1370 
  1371 * The constants cpair, cfst, and csnd have been removed in favor of
  1372 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  1373 
  1374 
  1375 *** ML ***
  1376 
  1377 * Antiquotations for basic formal entities:
  1378 
  1379     @{class NAME}         -- type class
  1380     @{class_syntax NAME}  -- syntax representation of the above
  1381 
  1382     @{type_name NAME}     -- logical type
  1383     @{type_abbrev NAME}   -- type abbreviation
  1384     @{nonterminal NAME}   -- type of concrete syntactic category
  1385     @{type_syntax NAME}   -- syntax representation of any of the above
  1386 
  1387     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  1388     @{const_abbrev NAME}  -- abbreviated constant
  1389     @{const_syntax NAME}  -- syntax representation of any of the above
  1390 
  1391 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  1392 syntax constant (cf. 'syntax' command).
  1393 
  1394 * Antiquotation @{make_string} inlines a function to print arbitrary
  1395 values similar to the ML toplevel.  The result is compiler dependent
  1396 and may fall back on "?" in certain situations.
  1397 
  1398 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  1399 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  1400 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  1401 not work with the asynchronous Isar document model.
  1402 
  1403 * Configuration options now admit dynamic default values, depending on
  1404 the context or even global references.
  1405 
  1406 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  1407 uses an efficient external library if available (for Poly/ML).
  1408 
  1409 * Renamed some important ML structures, while keeping the old names
  1410 for some time as aliases within the structure Legacy:
  1411 
  1412   OuterKeyword  ~>  Keyword
  1413   OuterLex      ~>  Token
  1414   OuterParse    ~>  Parse
  1415   OuterSyntax   ~>  Outer_Syntax
  1416   PrintMode     ~>  Print_Mode
  1417   SpecParse     ~>  Parse_Spec
  1418   ThyInfo       ~>  Thy_Info
  1419   ThyLoad       ~>  Thy_Load
  1420   ThyOutput     ~>  Thy_Output
  1421   TypeInfer     ~>  Type_Infer
  1422 
  1423 Note that "open Legacy" simplifies porting of sources, but forgetting
  1424 to remove it again will complicate porting again in the future.
  1425 
  1426 * Most operations that refer to a global context are named
  1427 accordingly, e.g. Simplifier.global_context or
  1428 ProofContext.init_global.  There are some situations where a global
  1429 context actually works, but under normal circumstances one needs to
  1430 pass the proper local context through the code!
  1431 
  1432 * Discontinued old TheoryDataFun with its copy/init operation -- data
  1433 needs to be pure.  Functor Theory_Data_PP retains the traditional
  1434 Pretty.pp argument to merge, which is absent in the standard
  1435 Theory_Data version.
  1436 
  1437 * Sorts.certify_sort and derived "cert" operations for types and terms
  1438 no longer minimize sorts.  Thus certification at the boundary of the
  1439 inference kernel becomes invariant under addition of class relations,
  1440 which is an important monotonicity principle.  Sorts are now minimized
  1441 in the syntax layer only, at the boundary between the end-user and the
  1442 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  1443 explicitly in rare situations.
  1444 
  1445 * Renamed old-style Drule.standard to Drule.export_without_context, to
  1446 emphasize that this is in no way a standard operation.
  1447 INCOMPATIBILITY.
  1448 
  1449 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  1450 usual for resolution.  Rare INCOMPATIBILITY.
  1451 
  1452 * Renamed varify/unvarify operations to varify_global/unvarify_global
  1453 to emphasize that these only work in a global situation (which is
  1454 quite rare).
  1455 
  1456 * Curried take and drop in library.ML; negative length is interpreted
  1457 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  1458 
  1459 * Proof terms: type substitutions on proof constants now use canonical
  1460 order of type variables.  INCOMPATIBILITY for tools working with proof
  1461 terms.
  1462 
  1463 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  1464 may no longer carry premises.  User-level specifications are
  1465 transformed accordingly by Thm.add_axiom/add_def.
  1466 
  1467 
  1468 *** System ***
  1469 
  1470 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  1471 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  1472 proof terms are enabled unconditionally in the new HOL-Proofs image.
  1473 
  1474 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  1475 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  1476 respectively.
  1477 
  1478 * Old lib/scripts/polyml-platform is superseded by the
  1479 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  1480 variant, even on a 64 bit machine.  The following example setting
  1481 prefers 64 bit if available:
  1482 
  1483   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  1484 
  1485 * The preliminary Isabelle/jEdit application demonstrates the emerging
  1486 Isabelle/Scala layer for advanced prover interaction and integration.
  1487 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  1488 component.
  1489 
  1490 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  1491 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  1492 similar to the default assignment of the document preparation system
  1493 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  1494 provides some operations for direct access to the font without asking
  1495 the user for manual installation.
  1496 
  1497 
  1498 
  1499 New in Isabelle2009-1 (December 2009)
  1500 -------------------------------------
  1501 
  1502 *** General ***
  1503 
  1504 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  1505 one backslash should be used, even in ML sources.
  1506 
  1507 
  1508 *** Pure ***
  1509 
  1510 * Locale interpretation propagates mixins along the locale hierarchy.
  1511 The currently only available mixins are the equations used to map
  1512 local definitions to terms of the target domain of an interpretation.
  1513 
  1514 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  1515 loc" to print all interpretations of locale "loc" in the theory.
  1516 Interpretations in proofs are not shown.
  1517 
  1518 * Thoroughly revised locales tutorial.  New section on conditional
  1519 interpretation.
  1520 
  1521 * On instantiation of classes, remaining undefined class parameters
  1522 are formally declared.  INCOMPATIBILITY.
  1523 
  1524 
  1525 *** Document preparation ***
  1526 
  1527 * New generalized style concept for printing terms: @{foo (style) ...}
  1528 instead of @{foo_style style ...}  (old form is still retained for
  1529 backward compatibility).  Styles can be also applied for
  1530 antiquotations prop, term_type and typeof.
  1531 
  1532 
  1533 *** HOL ***
  1534 
  1535 * New proof method "smt" for a combination of first-order logic with
  1536 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  1537 fixed-size bitvectors; there is also basic support for higher-order
  1538 features (esp. lambda abstractions).  It is an incomplete decision
  1539 procedure based on external SMT solvers using the oracle mechanism;
  1540 for the SMT solver Z3, this method is proof-producing.  Certificates
  1541 are provided to avoid calling the external solvers solely for
  1542 re-checking proofs.  Due to a remote SMT service there is no need for
  1543 installing SMT solvers locally.  See src/HOL/SMT.
  1544 
  1545 * New commands to load and prove verification conditions generated by
  1546 the Boogie program verifier or derived systems (e.g. the Verifying C
  1547 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1548 
  1549 * New counterexample generator tool 'nitpick' based on the Kodkod
  1550 relational model finder.  See src/HOL/Tools/Nitpick and
  1551 src/HOL/Nitpick_Examples.
  1552 
  1553 * New commands 'code_pred' and 'values' to invoke the predicate
  1554 compiler and to enumerate values of inductive predicates.
  1555 
  1556 * A tabled implementation of the reflexive transitive closure.
  1557 
  1558 * New implementation of quickcheck uses generic code generator;
  1559 default generators are provided for all suitable HOL types, records
  1560 and datatypes.  Old quickcheck can be re-activated importing theory
  1561 Library/SML_Quickcheck.
  1562 
  1563 * New testing tool Mirabelle for automated proof tools.  Applies
  1564 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1565 every proof step in a theory.  To be used in batch mode via the
  1566 "mirabelle" utility.
  1567 
  1568 * New proof method "sos" (sum of squares) for nonlinear real
  1569 arithmetic (originally due to John Harison). It requires theory
  1570 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1571 works well in practice on quantifier-free real arithmetic with +, -,
  1572 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1573 inequalities between polynomials.  It makes use of external
  1574 semidefinite programming solvers.  Method "sos" generates a
  1575 certificate that can be pasted into the proof thus avoiding the need
  1576 to call an external tool every time the proof is checked.  See
  1577 src/HOL/Library/Sum_Of_Squares.
  1578 
  1579 * New method "linarith" invokes existing linear arithmetic decision
  1580 procedure only.
  1581 
  1582 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1583 
  1584 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1585 Causes full type information to be output to the ATPs.  This slows
  1586 ATPs down considerably but eliminates a source of unsound "proofs"
  1587 that fail later.
  1588 
  1589 * New method "metisFT": A version of metis that uses full type
  1590 information in order to avoid failures of proof reconstruction.
  1591 
  1592 * New evaluator "approximate" approximates an real valued term using
  1593 the same method as the approximation method.
  1594 
  1595 * Method "approximate" now supports arithmetic expressions as
  1596 boundaries of intervals and implements interval splitting and Taylor
  1597 series expansion.
  1598 
  1599 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1600 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1601 
  1602 * New theory SupInf of the supremum and infimum operators for sets of
  1603 reals.
  1604 
  1605 * New theory Probability, which contains a development of measure
  1606 theory, eventually leading to Lebesgue integration and probability.
  1607 
  1608 * Extended Multivariate Analysis to include derivation and Brouwer's
  1609 fixpoint theorem.
  1610 
  1611 * Reorganization of number theory, INCOMPATIBILITY:
  1612   - new number theory development for nat and int, in theories Divides
  1613     and GCD as well as in new session Number_Theory
  1614   - some constants and facts now suffixed with _nat and _int
  1615     accordingly
  1616   - former session NumberTheory now named Old_Number_Theory, including
  1617     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1618   - moved theory Pocklington from src/HOL/Library to
  1619     src/HOL/Old_Number_Theory
  1620 
  1621 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1622 lcm of finite and infinite sets. It is shown that they form a complete
  1623 lattice.
  1624 
  1625 * Class semiring_div requires superclass no_zero_divisors and proof of
  1626 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1627 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1628 generalized to class semiring_div, subsuming former theorems
  1629 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1630 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1631 INCOMPATIBILITY.
  1632 
  1633 * Refinements to lattice classes and sets:
  1634   - less default intro/elim rules in locale variant, more default
  1635     intro/elim rules in class variant: more uniformity
  1636   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1637     le_inf_iff
  1638   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1639     sup_aci)
  1640   - renamed ACI to inf_sup_aci
  1641   - new class "boolean_algebra"
  1642   - class "complete_lattice" moved to separate theory
  1643     "Complete_Lattice"; corresponding constants (and abbreviations)
  1644     renamed and with authentic syntax:
  1645     Set.Inf ~>    Complete_Lattice.Inf
  1646     Set.Sup ~>    Complete_Lattice.Sup
  1647     Set.INFI ~>   Complete_Lattice.INFI
  1648     Set.SUPR ~>   Complete_Lattice.SUPR
  1649     Set.Inter ~>  Complete_Lattice.Inter
  1650     Set.Union ~>  Complete_Lattice.Union
  1651     Set.INTER ~>  Complete_Lattice.INTER
  1652     Set.UNION ~>  Complete_Lattice.UNION
  1653   - authentic syntax for
  1654     Set.Pow
  1655     Set.image
  1656   - mere abbreviations:
  1657     Set.empty               (for bot)
  1658     Set.UNIV                (for top)
  1659     Set.inter               (for inf, formerly Set.Int)
  1660     Set.union               (for sup, formerly Set.Un)
  1661     Complete_Lattice.Inter  (for Inf)
  1662     Complete_Lattice.Union  (for Sup)
  1663     Complete_Lattice.INTER  (for INFI)
  1664     Complete_Lattice.UNION  (for SUPR)
  1665   - object-logic definitions as far as appropriate
  1666 
  1667 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1668 Un_subset_iff are explicitly deleted as default simp rules; then also
  1669 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1670 deleted to achieve the desired effect.
  1671 
  1672 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1673 rules by default any longer; the same applies to min_max.inf_absorb1
  1674 etc.  INCOMPATIBILITY.
  1675 
  1676 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1677 pred_set_conv by default.  INCOMPATIBILITY.
  1678 
  1679 * Power operations on relations and functions are now one dedicated
  1680 constant "compow" with infix syntax "^^".  Power operation on
  1681 multiplicative monoids retains syntax "^" and is now defined generic
  1682 in class power.  INCOMPATIBILITY.
  1683 
  1684 * Relation composition "R O S" now has a more standard argument order:
  1685 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1686 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1687 break, since the O_assoc rule was not rewritten like this.  Fix using
  1688 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1689 
  1690 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1691 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1692 INCOMPATIBILITY.
  1693 
  1694 * Most rules produced by inductive and datatype package have mandatory
  1695 prefixes.  INCOMPATIBILITY.
  1696 
  1697 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1698 the attribute of the same name.  Each of the theorems in the list
  1699 DERIV_intros assumes composition with an additional function and
  1700 matches a variable to the derivative, which has to be solved by the
  1701 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1702 of most elementary terms.  Former Maclauren.DERIV_tac and
  1703 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1704 INCOMPATIBILITY.
  1705 
  1706 * Code generator attributes follow the usual underscore convention:
  1707     code_unfold     replaces    code unfold
  1708     code_post       replaces    code post
  1709     etc.
  1710   INCOMPATIBILITY.
  1711 
  1712 * Renamed methods:
  1713     sizechange -> size_change
  1714     induct_scheme -> induction_schema
  1715   INCOMPATIBILITY.
  1716 
  1717 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1718 INCOMPATIBILITY, use "undefined" directly.
  1719 
  1720 * Renamed theorems:
  1721     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1722     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1723     Suc_plus1 -> Suc_eq_plus1
  1724     *anti_sym -> *antisym*
  1725     vector_less_eq_def -> vector_le_def
  1726   INCOMPATIBILITY.
  1727 
  1728 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1729 INCOMPATIBILITY.
  1730 
  1731 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1732 INCOMPATIBILITY.
  1733 
  1734 
  1735 *** HOLCF ***
  1736 
  1737 * Theory Representable defines a class "rep" of domains that are
  1738 representable (via an ep-pair) in the universal domain type "udom".
  1739 Instances are provided for all type constructors defined in HOLCF.
  1740 
  1741 * The 'new_domain' command is a purely definitional version of the
  1742 domain package, for representable domains.  Syntax is identical to the
  1743 old domain package.  The 'new_domain' package also supports indirect
  1744 recursion using previously-defined type constructors.  See
  1745 src/HOLCF/ex/New_Domain.thy for examples.
  1746 
  1747 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1748 on the left-hand side of an equation, and then performs
  1749 simplification.  Rewriting is done using rules declared with the
  1750 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1751 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1752 
  1753 * The pattern-match compiler in 'fixrec' can now handle constructors
  1754 with HOL function types.  Pattern-match combinators for the Pair
  1755 constructor are pre-configured.
  1756 
  1757 * The 'fixrec' package now produces better fixed-point induction rules
  1758 for mutually-recursive definitions:  Induction rules have conclusions
  1759 of the form "P foo bar" instead of "P <foo, bar>".
  1760 
  1761 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1762 been renamed to "below".  The name "below" now replaces "less" in many
  1763 theorem names.  (Legacy theorem names using "less" are still supported
  1764 as well.)
  1765 
  1766 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1767 patterns can be used to generate strictness rules, or to make
  1768 functions more strict (much like the bang-patterns supported by the
  1769 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1770 examples.
  1771 
  1772 
  1773 *** ML ***
  1774 
  1775 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1776 errors and run-time exceptions, including detailed source positions.
  1777 
  1778 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1779 identified entries, with some additional information such as source
  1780 position, logical grouping etc.
  1781 
  1782 * Theory and context data is now introduced by the simplified and
  1783 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1784 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1785 copy operation) is still available for some time.
  1786 
  1787 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1788 provides a high-level programming interface to synchronized state
  1789 variables with atomic update.  This works via pure function
  1790 application within a critical section -- its runtime should be as
  1791 short as possible; beware of deadlocks if critical code is nested,
  1792 either directly or indirectly via other synchronized variables!
  1793 
  1794 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1795 wraps raw ML references, explicitly indicating their non-thread-safe
  1796 behaviour.  The Isar toplevel keeps this structure open, to
  1797 accommodate Proof General as well as quick and dirty interactive
  1798 experiments with references.
  1799 
  1800 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1801 parallel tactical reasoning.
  1802 
  1803 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1804 are similar to SUBPROOF, but are slightly more flexible: only the
  1805 specified parts of the subgoal are imported into the context, and the
  1806 body tactic may introduce new subgoals and schematic variables.
  1807 
  1808 * Old tactical METAHYPS, which does not observe the proof context, has
  1809 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1810 or Subgoal.FOCUS etc.
  1811 
  1812 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  1813 functors have their own ML name space there is no point to mark them
  1814 separately.)  Minor INCOMPATIBILITY.
  1815 
  1816 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  1817 
  1818 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  1819 INCOMPATIBILITY.
  1820 
  1821 * Operations of structure Skip_Proof no longer require quick_and_dirty
  1822 mode, which avoids critical setmp.
  1823 
  1824 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  1825 combinators for "args".  INCOMPATIBILITY, need to use simplified
  1826 Attrib/Method.setup introduced in Isabelle2009.
  1827 
  1828 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  1829 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  1830 last resort.  INCOMPATIBILITY.
  1831 
  1832 * Display.pretty_thm now requires a proper context (cf. former
  1833 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  1834 or even Display.pretty_thm_without_context as last resort.
  1835 INCOMPATIBILITY.
  1836 
  1837 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  1838 Syntax.pretty_typ/term directly, preferably with proper context
  1839 instead of global theory.
  1840 
  1841 
  1842 *** System ***
  1843 
  1844 * Further fine tuning of parallel proof checking, scales up to 8 cores
  1845 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  1846 usedir option -q.
  1847 
  1848 * Support for additional "Isabelle components" via etc/components, see
  1849 also the system manual.
  1850 
  1851 * The isabelle makeall tool now operates on all components with
  1852 IsaMakefile, not just hardwired "logics".
  1853 
  1854 * Removed "compress" option from isabelle-process and isabelle usedir;
  1855 this is always enabled.
  1856 
  1857 * Discontinued support for Poly/ML 4.x versions.
  1858 
  1859 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  1860 on a given logic image.  This requires the lighttpd webserver and is
  1861 currently supported on Linux only.
  1862 
  1863 
  1864 
  1865 New in Isabelle2009 (April 2009)
  1866 --------------------------------
  1867 
  1868 *** General ***
  1869 
  1870 * Simplified main Isabelle executables, with less surprises on
  1871 case-insensitive file-systems (such as Mac OS).
  1872 
  1873   - The main Isabelle tool wrapper is now called "isabelle" instead of
  1874     "isatool."
  1875 
  1876   - The former "isabelle" alias for "isabelle-process" has been
  1877     removed (should rarely occur to regular users).
  1878 
  1879   - The former "isabelle-interface" and its alias "Isabelle" have been
  1880     removed (interfaces are now regular Isabelle tools).
  1881 
  1882 Within scripts and make files, the Isabelle environment variables
  1883 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  1884 respectively.  (The latter are still available as legacy feature.)
  1885 
  1886 The old isabelle-interface wrapper could react in confusing ways if
  1887 the interface was uninstalled or changed otherwise.  Individual
  1888 interface tool configuration is now more explicit, see also the
  1889 Isabelle system manual.  In particular, Proof General is now available
  1890 via "isabelle emacs".
  1891 
  1892 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  1893 purge installed copies of Isabelle executables and re-run "isabelle
  1894 install -p ...", or use symlinks.
  1895 
  1896 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  1897 old ~/isabelle, which was slightly non-standard and apt to cause
  1898 surprises on case-insensitive file-systems (such as Mac OS).
  1899 
  1900 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  1901 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  1902 care is required when using older releases of Isabelle.  Note that
  1903 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  1904 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  1905 
  1906 * Proofs of fully specified statements are run in parallel on
  1907 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  1908 a regular 4-core machine, if the initial heap space is made reasonably
  1909 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  1910 
  1911 * The main reference manuals ("isar-ref", "implementation", and
  1912 "system") have been updated and extended.  Formally checked references
  1913 as hyperlinks are now available uniformly.
  1914 
  1915 
  1916 *** Pure ***
  1917 
  1918 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  1919 respects.  The most important changes are listed below.  See the
  1920 Tutorial on Locales ("locales" manual) for details.
  1921 
  1922 - In locale expressions, instantiation replaces renaming.  Parameters
  1923 must be declared in a for clause.  To aid compatibility with previous
  1924 parameter inheritance, in locale declarations, parameters that are not
  1925 'touched' (instantiation position "_" or omitted) are implicitly added
  1926 with their syntax at the beginning of the for clause.
  1927 
  1928 - Syntax from abbreviations and definitions in locales is available in
  1929 locale expressions and context elements.  The latter is particularly
  1930 useful in locale declarations.
  1931 
  1932 - More flexible mechanisms to qualify names generated by locale
  1933 expressions.  Qualifiers (prefixes) may be specified in locale
  1934 expressions, and can be marked as mandatory (syntax: "name!:") or
  1935 optional (syntax "name?:").  The default depends for plain "name:"
  1936 depends on the situation where a locale expression is used: in
  1937 commands 'locale' and 'sublocale' prefixes are optional, in
  1938 'interpretation' and 'interpret' prefixes are mandatory.  The old
  1939 implicit qualifiers derived from the parameter names of a locale are
  1940 no longer generated.
  1941 
  1942 - Command "sublocale l < e" replaces "interpretation l < e".  The
  1943 instantiation clause in "interpretation" and "interpret" (square
  1944 brackets) is no longer available.  Use locale expressions.
  1945 
  1946 - When converting proof scripts, mandatory qualifiers in
  1947 'interpretation' and 'interpret' should be retained by default, even
  1948 if this is an INCOMPATIBILITY compared to former behavior.  In the
  1949 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  1950 in locale expressions range over a single locale instance only.
  1951 
  1952 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  1953 In existing theorem specifications replace the includes element by the
  1954 respective context elements of the included locale, omitting those
  1955 that are already present in the theorem specification.  Multiple
  1956 assume elements of a locale should be replaced by a single one
  1957 involving the locale predicate.  In the proof body, declarations (most
  1958 notably theorems) may be regained by interpreting the respective
  1959 locales in the proof context as required (command "interpret").
  1960 
  1961 If using "includes" in replacement of a target solely because the
  1962 parameter types in the theorem are not as general as in the target,
  1963 consider declaring a new locale with additional type constraints on
  1964 the parameters (context element "constrains").
  1965 
  1966 - Discontinued "locale (open)".  INCOMPATIBILITY.
  1967 
  1968 - Locale interpretation commands no longer attempt to simplify goal.
  1969 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  1970 methods intro_locales and unfold_locales to clarify.
  1971 
  1972 - Locale interpretation commands no longer accept interpretation
  1973 attributes.  INCOMPATIBILITY.
  1974 
  1975 * Class declaration: so-called "base sort" must not be given in import
  1976 list any longer, but is inferred from the specification.  Particularly
  1977 in HOL, write
  1978 
  1979     class foo = ...
  1980 
  1981 instead of
  1982 
  1983     class foo = type + ...
  1984 
  1985 * Class target: global versions of theorems stemming do not carry a
  1986 parameter prefix any longer.  INCOMPATIBILITY.
  1987 
  1988 * Class 'instance' command no longer accepts attached definitions.
  1989 INCOMPATIBILITY, use proper 'instantiation' target instead.
  1990 
  1991 * Recovered hiding of consts, which was accidentally broken in
  1992 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  1993 makes c inaccessible; consider using ``hide (open) const c'' instead.
  1994 
  1995 * Slightly more coherent Pure syntax, with updated documentation in
  1996 isar-ref manual.  Removed locales meta_term_syntax and
  1997 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  1998 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  1999 directly in regular applications.
  2000 
  2001 * There is a new syntactic category "float_const" for signed decimal
  2002 fractions (e.g. 123.45 or -123.45).
  2003 
  2004 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  2005 interface with 'setup' command instead.
  2006 
  2007 * Command 'local_setup' is similar to 'setup', but operates on a local
  2008 theory context.
  2009 
  2010 * The 'axiomatization' command now only works within a global theory
  2011 context.  INCOMPATIBILITY.
  2012 
  2013 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  2014 hypotheses.  Sorts required in the course of reasoning need to be
  2015 covered by the constraints in the initial statement, completed by the
  2016 type instance information of the background theory.  Non-trivial sort
  2017 hypotheses, which rarely occur in practice, may be specified via
  2018 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  2019 
  2020   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  2021 
  2022 The result contains an implicit sort hypotheses as before --
  2023 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  2024 normalization.
  2025 
  2026 * Generalized Isar history, with support for linear undo, direct state
  2027 addressing etc.
  2028 
  2029 * Changed defaults for unify configuration options:
  2030 
  2031   unify_trace_bound = 50 (formerly 25)
  2032   unify_search_bound = 60 (formerly 30)
  2033 
  2034 * Different bookkeeping for code equations (INCOMPATIBILITY):
  2035 
  2036   a) On theory merge, the last set of code equations for a particular
  2037      constant is taken (in accordance with the policy applied by other
  2038      parts of the code generator framework).
  2039 
  2040   b) Code equations stemming from explicit declarations (e.g. code
  2041      attribute) gain priority over default code equations stemming
  2042      from definition, primrec, fun etc.
  2043 
  2044 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  2045 
  2046 * Unified theorem tables for both code generators.  Thus [code
  2047 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  2048 
  2049 * Command 'find_consts' searches for constants based on type and name
  2050 patterns, e.g.
  2051 
  2052     find_consts "_ => bool"
  2053 
  2054 By default, matching is against subtypes, but it may be restricted to
  2055 the whole type.  Searching by name is possible.  Multiple queries are
  2056 conjunctive and queries may be negated by prefixing them with a
  2057 hyphen:
  2058 
  2059     find_consts strict: "_ => bool" name: "Int" -"int => int"
  2060 
  2061 * New 'find_theorems' criterion "solves" matches theorems that
  2062 directly solve the current goal (modulo higher-order unification).
  2063 
  2064 * Auto solve feature for main theorem statements: whenever a new goal
  2065 is stated, "find_theorems solves" is called; any theorems that could
  2066 solve the lemma directly are listed as part of the goal state.
  2067 Cf. associated options in Proof General Isabelle settings menu,
  2068 enabled by default, with reasonable timeout for pathological cases of
  2069 higher-order unification.
  2070 
  2071 
  2072 *** Document preparation ***
  2073 
  2074 * Antiquotation @{lemma} now imitates a regular terminal proof,
  2075 demanding keyword 'by' and supporting the full method expression
  2076 syntax just like the Isar command 'by'.
  2077 
  2078 
  2079 *** HOL ***
  2080 
  2081 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  2082 points Main and Complex_Main remain as before.
  2083 
  2084 * Logic image HOL-Plain provides a minimal HOL with the most important
  2085 tools available (inductive, datatype, primrec, ...).  This facilitates
  2086 experimentation and tool development.  Note that user applications
  2087 (and library theories) should never refer to anything below theory
  2088 Main, as before.
  2089 
  2090 * Logic image HOL-Main stops at theory Main, and thus facilitates
  2091 experimentation due to shorter build times.
  2092 
  2093 * Logic image HOL-NSA contains theories of nonstandard analysis which
  2094 were previously part of former HOL-Complex.  Entry point Hyperreal
  2095 remains valid, but theories formerly using Complex_Main should now use
  2096 new entry point Hypercomplex.
  2097 
  2098 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  2099 Posix processes.  Avoids potentially expensive forking of the ML
  2100 process.  New thread-based implementation also works on non-Unix
  2101 platforms (Cygwin).  Provers are no longer hardwired, but defined
  2102 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  2103 commands are covered in the isar-ref manual.
  2104 
  2105 * Wrapper scripts for remote SystemOnTPTP service allows to use
  2106 sledgehammer without local ATP installation (Vampire etc.). Other
  2107 provers may be included via suitable ML wrappers, see also
  2108 src/HOL/ATP_Linkup.thy.
  2109 
  2110 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  2111 menu.
  2112 
  2113 * The metis method no longer fails because the theorem is too trivial
  2114 (contains the empty clause).
  2115 
  2116 * The metis method now fails in the usual manner, rather than raising
  2117 an exception, if it determines that it cannot prove the theorem.
  2118 
  2119 * Method "coherent" implements a prover for coherent logic (see also
  2120 src/Tools/coherent.ML).
  2121 
  2122 * Constants "undefined" and "default" replace "arbitrary".  Usually
  2123 "undefined" is the right choice to replace "arbitrary", though
  2124 logically there is no difference.  INCOMPATIBILITY.
  2125 
  2126 * Command "value" now integrates different evaluation mechanisms.  The
  2127 result of the first successful evaluation mechanism is printed.  In
  2128 square brackets a particular named evaluation mechanisms may be
  2129 specified (currently, [SML], [code] or [nbe]).  See further
  2130 src/HOL/ex/Eval_Examples.thy.
  2131 
  2132 * Normalization by evaluation now allows non-leftlinear equations.
  2133 Declare with attribute [code nbe].
  2134 
  2135 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  2136 as the structured Isar versions "cases" and "induct", cf. the
  2137 corresponding "cases" and "induct" attributes.  Mutual induction rules
  2138 are now presented as a list of individual projections
  2139 (e.g. foo_bar.inducts for types foo and bar); the old format with
  2140 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  2141 rare situations a different rule is selected --- notably nested tuple
  2142 elimination instead of former prod.exhaust: use explicit (case_tac t
  2143 rule: prod.exhaust) here.
  2144 
  2145 * Attributes "cases", "induct", "coinduct" support "del" option.
  2146 
  2147 * Removed fact "case_split_thm", which duplicates "case_split".
  2148 
  2149 * The option datatype has been moved to a new theory Option.  Renamed
  2150 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  2151 
  2152 * New predicate "strict_mono" classifies strict functions on partial
  2153 orders.  With strict functions on linear orders, reasoning about
  2154 (in)equalities is facilitated by theorems "strict_mono_eq",
  2155 "strict_mono_less_eq" and "strict_mono_less".
  2156 
  2157 * Some set operations are now proper qualified constants with
  2158 authentic syntax.  INCOMPATIBILITY:
  2159 
  2160     op Int ~>   Set.Int
  2161     op Un ~>    Set.Un
  2162     INTER ~>    Set.INTER
  2163     UNION ~>    Set.UNION
  2164     Inter ~>    Set.Inter
  2165     Union ~>    Set.Union
  2166     {} ~>       Set.empty
  2167     UNIV ~>     Set.UNIV
  2168 
  2169 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  2170 theory Set.
  2171 
  2172 * Auxiliary class "itself" has disappeared -- classes without any
  2173 parameter are treated as expected by the 'class' command.
  2174 
  2175 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  2176 
  2177 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  2178 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  2179 
  2180 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  2181 method "approximation".  It proves formulas on real values by using
  2182 interval arithmetic.  In the formulas are also the transcendental
  2183 functions sin, cos, tan, atan, ln, exp and the constant pi are
  2184 allowed. For examples see
  2185 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  2186 
  2187 * Theory "Reflection" now resides in HOL/Library.
  2188 
  2189 * Entry point to Word library now simply named "Word".
  2190 INCOMPATIBILITY.
  2191 
  2192 * Made source layout more coherent with logical distribution
  2193 structure:
  2194 
  2195     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  2196     src/HOL/Library/Code_Message.thy ~> src/HOL/
  2197     src/HOL/Library/GCD.thy ~> src/HOL/
  2198     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  2199     src/HOL/Library/Parity.thy ~> src/HOL/
  2200     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  2201     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  2202     src/HOL/Real/Lubs.thy ~> src/HOL/
  2203     src/HOL/Real/PReal.thy ~> src/HOL/
  2204     src/HOL/Real/Rational.thy ~> src/HOL/
  2205     src/HOL/Real/RComplete.thy ~> src/HOL/
  2206     src/HOL/Real/RealDef.thy ~> src/HOL/
  2207     src/HOL/Real/RealPow.thy ~> src/HOL/
  2208     src/HOL/Real/Real.thy ~> src/HOL/
  2209     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  2210     src/HOL/Complex/Complex.thy ~> src/HOL/
  2211     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  2212     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  2213     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  2214     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  2215     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  2216     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  2217     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  2218     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  2219     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  2220     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  2221     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  2222     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  2223     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  2224     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  2225     src/HOL/Real/Float ~> src/HOL/Library/
  2226     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  2227     src/HOL/Real/RealVector.thy ~> src/HOL/
  2228 
  2229     src/HOL/arith_data.ML ~> src/HOL/Tools
  2230     src/HOL/hologic.ML ~> src/HOL/Tools
  2231     src/HOL/simpdata.ML ~> src/HOL/Tools
  2232     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  2233     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  2234     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  2235     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  2236     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  2237     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  2238     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  2239 
  2240     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  2241     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  2242     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  2243     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  2244     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  2245     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  2246 
  2247 * If methods "eval" and "evaluation" encounter a structured proof
  2248 state with !!/==>, only the conclusion is evaluated to True (if
  2249 possible), avoiding strange error messages.
  2250 
  2251 * Method "sizechange" automates termination proofs using (a
  2252 modification of) the size-change principle.  Requires SAT solver.  See
  2253 src/HOL/ex/Termination.thy for examples.
  2254 
  2255 * Simplifier: simproc for let expressions now unfolds if bound
  2256 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  2257 
  2258 * Method "arith": Linear arithmetic now ignores all inequalities when
  2259 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  2260 
  2261 * New attribute "arith" for facts that should always be used
  2262 automatically by arithmetic. It is intended to be used locally in
  2263 proofs, e.g.
  2264 
  2265   assumes [arith]: "x > 0"
  2266 
  2267 Global usage is discouraged because of possible performance impact.
  2268 
  2269 * New classes "top" and "bot" with corresponding operations "top" and
  2270 "bot" in theory Orderings; instantiation of class "complete_lattice"
  2271 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  2272 
  2273 * Changed definition lemma "less_fun_def" in order to provide an
  2274 instance for preorders on functions; use lemma "less_le" instead.
  2275 INCOMPATIBILITY.
  2276 
  2277 * Theory Orderings: class "wellorder" moved here, with explicit
  2278 induction rule "less_induct" as assumption.  For instantiation of
  2279 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  2280 INCOMPATIBILITY.
  2281 
  2282 * Theory Orderings: added class "preorder" as superclass of "order".
  2283 INCOMPATIBILITY: Instantiation proofs for order, linorder
  2284 etc. slightly changed.  Some theorems named order_class.* now named
  2285 preorder_class.*.
  2286 
  2287 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  2288 "diag" to "Id_on".
  2289 
  2290 * Theory Finite_Set: added a new fold combinator of type
  2291 
  2292   ('a => 'b => 'b) => 'b => 'a set => 'b
  2293 
  2294 Occasionally this is more convenient than the old fold combinator
  2295 which is now defined in terms of the new one and renamed to
  2296 fold_image.
  2297 
  2298 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  2299 and "ring_simps" have been replaced by "algebra_simps" (which can be
  2300 extended with further lemmas!).  At the moment both still exist but
  2301 the former will disappear at some point.
  2302 
  2303 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  2304 class recpower.  Type-specific simp rules for various recpower types
  2305 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  2306 
  2307 rat_power_0    -> power_0
  2308 rat_power_Suc  -> power_Suc
  2309 realpow_0      -> power_0
  2310 realpow_Suc    -> power_Suc
  2311 complexpow_0   -> power_0
  2312 complexpow_Suc -> power_Suc
  2313 power_poly_0   -> power_0
  2314 power_poly_Suc -> power_Suc
  2315 
  2316 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  2317 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  2318 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  2319 of lemmas from Divides has been generalized from nat to class
  2320 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  2321 renames resulting from duplicate elimination:
  2322 
  2323     dvd_def_mod ~>          dvd_eq_mod_eq_0
  2324     zero_dvd_iff ~>         dvd_0_left_iff
  2325     dvd_0 ~>                dvd_0_right
  2326     DIVISION_BY_ZERO_DIV ~> div_by_0
  2327     DIVISION_BY_ZERO_MOD ~> mod_by_0
  2328     mult_div ~>             div_mult_self2_is_id
  2329     mult_mod ~>             mod_mult_self2_is_0
  2330 
  2331 * Theory IntDiv: removed many lemmas that are instances of class-based
  2332 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  2333 rename old lemmas as follows:
  2334 
  2335 dvd_diff               -> nat_dvd_diff
  2336 dvd_zminus_iff         -> dvd_minus_iff
  2337 mod_add1_eq            -> mod_add_eq
  2338 mod_mult1_eq           -> mod_mult_right_eq
  2339 mod_mult1_eq'          -> mod_mult_left_eq
  2340 mod_mult_distrib_mod   -> mod_mult_eq
  2341 nat_mod_add_left_eq    -> mod_add_left_eq
  2342 nat_mod_add_right_eq   -> mod_add_right_eq
  2343 nat_mod_div_trivial    -> mod_div_trivial
  2344 nat_mod_mod_trivial    -> mod_mod_trivial
  2345 zdiv_zadd_self1        -> div_add_self1
  2346 zdiv_zadd_self2        -> div_add_self2
  2347 zdiv_zmult_self1       -> div_mult_self2_is_id
  2348 zdiv_zmult_self2       -> div_mult_self1_is_id
  2349 zdvd_triv_left         -> dvd_triv_left
  2350 zdvd_triv_right        -> dvd_triv_right
  2351 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  2352 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  2353 zmod_zadd_left_eq      -> mod_add_left_eq
  2354 zmod_zadd_right_eq     -> mod_add_right_eq
  2355 zmod_zadd_self1        -> mod_add_self1
  2356 zmod_zadd_self2        -> mod_add_self2
  2357 zmod_zadd1_eq          -> mod_add_eq
  2358 zmod_zdiff1_eq         -> mod_diff_eq
  2359 zmod_zdvd_zmod         -> mod_mod_cancel
  2360 zmod_zmod_cancel       -> mod_mod_cancel
  2361 zmod_zmult_self1       -> mod_mult_self2_is_0
  2362 zmod_zmult_self2       -> mod_mult_self1_is_0
  2363 zmod_1                 -> mod_by_1
  2364 zdiv_1                 -> div_by_1
  2365 zdvd_abs1              -> abs_dvd_iff
  2366 zdvd_abs2              -> dvd_abs_iff
  2367 zdvd_refl              -> dvd_refl
  2368 zdvd_trans             -> dvd_trans
  2369 zdvd_zadd              -> dvd_add
  2370 zdvd_zdiff             -> dvd_diff
  2371 zdvd_zminus_iff        -> dvd_minus_iff
  2372 zdvd_zminus2_iff       -> minus_dvd_iff
  2373 zdvd_zmultD            -> dvd_mult_right
  2374 zdvd_zmultD2           -> dvd_mult_left
  2375 zdvd_zmult_mono        -> mult_dvd_mono
  2376 zdvd_0_right           -> dvd_0_right
  2377 zdvd_0_left            -> dvd_0_left_iff
  2378 zdvd_1_left            -> one_dvd
  2379 zminus_dvd_iff         -> minus_dvd_iff
  2380 
  2381 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  2382 
  2383 * The real numbers offer decimal input syntax: 12.34 is translated
  2384 into 1234/10^2. This translation is not reversed upon output.
  2385 
  2386 * Theory Library/Polynomial defines an abstract type 'a poly of
  2387 univariate polynomials with coefficients of type 'a.  In addition to
  2388 the standard ring operations, it also supports div and mod.  Code
  2389 generation is also supported, using list-style constructors.
  2390 
  2391 * Theory Library/Inner_Product defines a class of real_inner for real
  2392 inner product spaces, with an overloaded operation inner :: 'a => 'a
  2393 => real.  Class real_inner is a subclass of real_normed_vector from
  2394 theory RealVector.
  2395 
  2396 * Theory Library/Product_Vector provides instances for the product
  2397 type 'a * 'b of several classes from RealVector and Inner_Product.
  2398 Definitions of addition, subtraction, scalar multiplication, norms,
  2399 and inner products are included.
  2400 
  2401 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  2402 addition to the field operations, numerals and case syntax are also
  2403 supported.
  2404 
  2405 * Theory Library/Diagonalize provides constructive version of Cantor's
  2406 first diagonalization argument.
  2407 
  2408 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  2409 zlcm (for int); carried together from various gcd/lcm developements in
  2410 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  2411 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  2412 may recover tupled syntax as follows:
  2413 
  2414     hide (open) const gcd
  2415     abbreviation gcd where
  2416       "gcd == (%(a, b). GCD.gcd a b)"
  2417     notation (output)
  2418       GCD.gcd ("gcd '(_, _')")
  2419 
  2420 The same works for lcm, zgcd, zlcm.
  2421 
  2422 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  2423 instantiations for algebraic structures.  Removed some duplicate
  2424 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  2425 
  2426 * ML antiquotation @{code} takes a constant as argument and generates
  2427 corresponding code in background and inserts name of the corresponding
  2428 resulting ML value/function/datatype constructor binding in place.
  2429 All occurrences of @{code} with a single ML block are generated
  2430 simultaneously.  Provides a generic and safe interface for
  2431 instrumentalizing code generation.  See
  2432 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  2433 In future you ought to refrain from ad-hoc compiling generated SML
  2434 code on the ML toplevel.  Note that (for technical reasons) @{code}
  2435 cannot refer to constants for which user-defined serializations are
  2436 set.  Refer to the corresponding ML counterpart directly in that
  2437 cases.
  2438 
  2439 * Command 'rep_datatype': instead of theorem names the command now
  2440 takes a list of terms denoting the constructors of the type to be
  2441 represented as datatype.  The characteristic theorems have to be
  2442 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  2443 have disappeared in favour of existing ones:
  2444 
  2445     unit_induct                 ~> unit.induct
  2446     prod_induct                 ~> prod.induct
  2447     sum_induct                  ~> sum.induct
  2448     Suc_Suc_eq                  ~> nat.inject
  2449     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  2450 
  2451 
  2452 *** HOL-Algebra ***
  2453 
  2454 * New locales for orders and lattices where the equivalence relation
  2455 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  2456 locales use a record structure with field eq for the equivalence.
  2457 
  2458 * New theory of factorial domains.
  2459 
  2460 * Units_l_inv and Units_r_inv are now simp rules by default.
  2461 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  2462 and/or r_inv will now also require deletion of these lemmas.
  2463 
  2464 * Renamed the following theorems, INCOMPATIBILITY:
  2465 
  2466 UpperD ~> Upper_memD
  2467 LowerD ~> Lower_memD
  2468 least_carrier ~> least_closed
  2469 greatest_carrier ~> greatest_closed
  2470 greatest_Lower_above ~> greatest_Lower_below
  2471 one_zero ~> carrier_one_zero
  2472 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  2473 
  2474 
  2475 *** HOL-Nominal ***
  2476 
  2477 * Nominal datatypes can now contain type-variables.
  2478 
  2479 * Commands 'nominal_inductive' and 'equivariance' work with local
  2480 theory targets.
  2481 
  2482 * Nominal primrec can now works with local theory targets and its
  2483 specification syntax now conforms to the general format as seen in
  2484 'inductive' etc.
  2485 
  2486 * Method "perm_simp" honours the standard simplifier attributes
  2487 (no_asm), (no_asm_use) etc.
  2488 
  2489 * The new predicate #* is defined like freshness, except that on the
  2490 left hand side can be a set or list of atoms.
  2491 
  2492 * Experimental command 'nominal_inductive2' derives strong induction
  2493 principles for inductive definitions.  In contrast to
  2494 'nominal_inductive', which can only deal with a fixed number of
  2495 binders, it can deal with arbitrary expressions standing for sets of
  2496 atoms to be avoided.  The only inductive definition we have at the
  2497 moment that needs this generalisation is the typing rule for Lets in
  2498 the algorithm W:
  2499 
  2500  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  2501  -----------------------------------------------------------------
  2502          Gamma |- Let x be t1 in t2 : T2
  2503 
  2504 In this rule one wants to avoid all the binders that are introduced by
  2505 "close Gamma T1".  We are looking for other examples where this
  2506 feature might be useful.  Please let us know.
  2507 
  2508 
  2509 *** HOLCF ***
  2510 
  2511 * Reimplemented the simplification procedure for proving continuity
  2512 subgoals.  The new simproc is extensible; users can declare additional
  2513 continuity introduction rules with the attribute [cont2cont].
  2514 
  2515 * The continuity simproc now uses a different introduction rule for
  2516 solving continuity subgoals on terms with lambda abstractions.  In
  2517 some rare cases the new simproc may fail to solve subgoals that the
  2518 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  2519 Potential INCOMPATIBILITY.
  2520 
  2521 * Command 'fixrec': specification syntax now conforms to the general
  2522 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  2523 examples.  INCOMPATIBILITY.
  2524 
  2525 
  2526 *** ZF ***
  2527 
  2528 * Proof of Zorn's Lemma for partial orders.
  2529 
  2530 
  2531 *** ML ***
  2532 
  2533 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  2534 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  2535 depends on multithreading, so timouts will not work before Poly/ML
  2536 5.2.1!
  2537 
  2538 * High-level support for concurrent ML programming, see
  2539 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  2540 particularly convenient to organize independent functional
  2541 computations.  The concept of "synchronized variables" provides a
  2542 higher-order interface for components with shared state, avoiding the
  2543 delicate details of mutexes and condition variables.  (Requires
  2544 Poly/ML 5.2.1 or later.)
  2545 
  2546 * ML bindings produced via Isar commands are stored within the Isar
  2547 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2548 become thread-safe and work with undo as expected (concerning
  2549 top-level bindings, not side-effects on global references).
  2550 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2551 compiler at runtime; really global bindings need to be given outside a
  2552 theory.  (Requires Poly/ML 5.2 or later.)
  2553 
  2554 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2555 context.  Top-level ML bindings are stored within the proof context in
  2556 a purely sequential fashion, disregarding the nested proof structure.
  2557 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2558 proof.  (Requires Poly/ML 5.2 or later.)
  2559 
  2560 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2561 and Method.setup, as well as Isar commands 'attribute_setup' and
  2562 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2563 existing code accordingly, or use plain 'setup' together with old
  2564 Method.add_method.
  2565 
  2566 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2567 to 'a -> thm, while results are always tagged with an authentic oracle
  2568 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2569 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2570 accordingly.  Note that extra performance may be gained by producing
  2571 the cterm carefully, avoiding slow Thm.cterm_of.
  2572 
  2573 * Simplified interface for defining document antiquotations via
  2574 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2575 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2576 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2577 examples.
  2578 
  2579 * More systematic treatment of long names, abstract name bindings, and
  2580 name space operations.  Basic operations on qualified names have been
  2581 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2582 Long_Name.append.  Old type bstring has been mostly replaced by
  2583 abstract type binding (see structure Binding), which supports precise
  2584 qualification by packages and local theory targets, as well as proper
  2585 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2586 bstring values into Binding.name, or better pass through abstract
  2587 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2588 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2589 
  2590 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2591 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2592 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2593 
  2594 * Disposed old type and term read functions (Sign.read_def_typ,
  2595 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2596 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2597 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2598 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2599 resort for legacy applications.
  2600 
  2601 * Disposed old declarations, tactics, tactic combinators that refer to
  2602 the simpset or claset of an implicit theory (such as Addsimps,
  2603 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2604 embedded ML text, or local_simpset_of with a proper context passed as
  2605 explicit runtime argument.
  2606 
  2607 * Rules and tactics that read instantiations (read_instantiate,
  2608 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2609 context, which is required for parsing and type-checking.  Moreover,
  2610 the variables are specified as plain indexnames, not string encodings
  2611 thereof.  INCOMPATIBILITY.
  2612 
  2613 * Generic Toplevel.add_hook interface allows to analyze the result of
  2614 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2615 for theorem dependency output of transactions resulting in a new
  2616 theory state.
  2617 
  2618 * ML antiquotations: block-structured compilation context indicated by
  2619 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2620 
  2621   @{binding name}                         - basic name binding
  2622   @{let ?pat = term}                      - term abbreviation (HO matching)
  2623   @{note name = fact}                     - fact abbreviation
  2624   @{thm fact}                             - singleton fact (with attributes)
  2625   @{thms fact}                            - general fact (with attributes)
  2626   @{lemma prop by method}                 - singleton goal
  2627   @{lemma prop by meth1 meth2}            - singleton goal
  2628   @{lemma prop1 ... propN by method}      - general goal
  2629   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2630   @{lemma (open) ...}                     - open derivation
  2631 
  2632 
  2633 *** System ***
  2634 
  2635 * The Isabelle "emacs" tool provides a specific interface to invoke
  2636 Proof General / Emacs, with more explicit failure if that is not
  2637 installed (the old isabelle-interface script silently falls back on
  2638 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2639 installation location of the Proof General distribution.
  2640 
  2641 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2642 the Isabelle process into a JVM/Scala application.  See
  2643 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2644 process wrapper has been discontinued.)
  2645 
  2646 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2647 
  2648 * Various status messages (with exact source position information) are
  2649 emitted, if proper markup print mode is enabled.  This allows
  2650 user-interface components to provide detailed feedback on internal
  2651 prover operations.
  2652 
  2653 
  2654 
  2655 New in Isabelle2008 (June 2008)
  2656 -------------------------------
  2657 
  2658 *** General ***
  2659 
  2660 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2661 and updated, with formally checked references as hyperlinks.
  2662 
  2663 * Theory loader: use_thy (and similar operations) no longer set the
  2664 implicit ML context, which was occasionally hard to predict and in
  2665 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2666 provides a proper context already.
  2667 
  2668 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2669 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2670 'use' within a theory file will do the job.
  2671 
  2672 * Name space merge now observes canonical order, i.e. the second space
  2673 is inserted into the first one, while existing entries in the first
  2674 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2675 swap theory imports.
  2676 
  2677 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2678 INCOMPATIBILITY in identifier syntax etc.
  2679 
  2680 * Outer syntax: string tokens no longer admit escaped white space,
  2681 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2682 white space without escapes.
  2683 
  2684 * Outer syntax: string tokens may contain arbitrary character codes
  2685 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2686 "foo_bar".
  2687 
  2688 
  2689 *** Pure ***
  2690 
  2691 * Context-dependent token translations.  Default setup reverts locally
  2692 fixed variables, and adds hilite markup for undeclared frees.
  2693 
  2694 * Unused theorems can be found using the new command 'unused_thms'.
  2695 There are three ways of invoking it:
  2696 
  2697 (1) unused_thms
  2698      Only finds unused theorems in the current theory.
  2699 
  2700 (2) unused_thms thy_1 ... thy_n -
  2701      Finds unused theorems in the current theory and all of its ancestors,
  2702      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2703 
  2704 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2705      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2706      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2707      their ancestors.
  2708 
  2709 In order to increase the readability of the list produced by
  2710 unused_thms, theorems that have been created by a particular instance
  2711 of a theory command such as 'inductive' or 'function' are considered
  2712 to belong to the same "group", meaning that if at least one theorem in
  2713 this group is used, the other theorems in the same group are no longer
  2714 reported as unused.  Moreover, if all theorems in the group are
  2715 unused, only one theorem in the group is displayed.
  2716 
  2717 Note that proof objects have to be switched on in order for
  2718 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2719 usually the case when using Proof General with the default settings).
  2720 
  2721 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2722 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2723 duplicate fact bindings, or even accidental fact duplications.  Note
  2724 that tools may maintain dynamically scoped facts systematically, using
  2725 PureThy.add_thms_dynamic.
  2726 
  2727 * Command 'hide' now allows to hide from "fact" name space as well.
  2728 
  2729 * Eliminated destructive theorem database, simpset, claset, and
  2730 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2731 update of theories within ML code.
  2732 
  2733 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2734 INCOMPATIBILITY, object-logics depending on former Pure require
  2735 additional setup PureThy.old_appl_syntax_setup; object-logics
  2736 depending on former CPure need to refer to Pure.
  2737 
  2738 * Commands 'use' and 'ML' are now purely functional, operating on
  2739 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2740 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2741 INCOMPATIBILITY.
  2742 
  2743 * Command 'setup': discontinued implicit version with ML reference.
  2744 
  2745 * Instantiation target allows for simultaneous specification of class
  2746 instance operations together with an instantiation proof.
  2747 Type-checking phase allows to refer to class operations uniformly.
  2748 See src/HOL/Complex/Complex.thy for an Isar example and
  2749 src/HOL/Library/Eval.thy for an ML example.
  2750 
  2751 * Indexing of literal facts: be more serious about including only
  2752 facts from the visible specification/proof context, but not the
  2753 background context (locale etc.).  Affects `prop` notation and method
  2754 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2755 situations.
  2756 
  2757 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2758 "(open)" option, which used to expose internal bound variables to the
  2759 proof text.
  2760 
  2761 * Isar statements: removed obsolete case "rule_context".
  2762 INCOMPATIBILITY, better use explicit fixes/assumes.
  2763 
  2764 * Locale proofs: default proof step now includes 'unfold_locales';
  2765 hence 'proof' without argument may be used to unfold locale
  2766 predicates.
  2767 
  2768 
  2769 *** Document preparation ***
  2770 
  2771 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2772 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2773 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2774 spot); renamed link color from "darkblue" to "linkcolor" (default
  2775 value unchanged, can be redefined via \definecolor); no longer sets
  2776 "a4paper" option (unnecessary or even intrusive).
  2777 
  2778 * Antiquotation @{lemma A method} proves proposition A by the given
  2779 method (either a method name or a method name plus (optional) method
  2780 arguments in parentheses) and prints A just like @{prop A}.
  2781 
  2782 
  2783 *** HOL ***
  2784 
  2785 * New primrec package.  Specification syntax conforms in style to
  2786 definition/function/....  No separate induction rule is provided.  The
  2787 "primrec" command distinguishes old-style and new-style specifications
  2788 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2789 When adjusting theories, beware: constants stemming from new-style
  2790 primrec specifications have authentic syntax.
  2791 
  2792 * Metis prover is now an order of magnitude faster, and also works
  2793 with multithreading.
  2794 
  2795 * Metis: the maximum number of clauses that can be produced from a
  2796 theorem is now given by the attribute max_clauses.  Theorems that
  2797 exceed this number are ignored, with a warning printed.
  2798 
  2799 * Sledgehammer no longer produces structured proofs by default. To
  2800 enable, declare [[sledgehammer_full = true]].  Attributes
  2801 reconstruction_modulus, reconstruction_sorts renamed
  2802 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2803 
  2804 * Method "induct_scheme" derives user-specified induction rules
  2805 from well-founded induction and completeness of patterns. This factors
  2806 out some operations that are done internally by the function package
  2807 and makes them available separately.  See
  2808 src/HOL/ex/Induction_Scheme.thy for examples.
  2809 
  2810 * More flexible generation of measure functions for termination
  2811 proofs: Measure functions can be declared by proving a rule of the
  2812 form "is_measure f" and giving it the [measure_function] attribute.
  2813 The "is_measure" predicate is logically meaningless (always true), and
  2814 just guides the heuristic.  To find suitable measure functions, the
  2815 termination prover sets up the goal "is_measure ?f" of the appropriate
  2816 type and generates all solutions by prolog-style backwards proof using
  2817 the declared rules.
  2818 
  2819 This setup also deals with rules like 
  2820 
  2821   "is_measure f ==> is_measure (list_size f)"
  2822 
  2823 which accommodates nested datatypes that recurse through lists.
  2824 Similar rules are predeclared for products and option types.
  2825 
  2826 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  2827 
  2828   INCOMPATIBILITIES:
  2829 
  2830   - Definitions of overloaded constants on sets have to be replaced by
  2831     definitions on => and bool.
  2832 
  2833   - Some definitions of overloaded operators on sets can now be proved
  2834     using the definitions of the operators on => and bool.  Therefore,
  2835     the following theorems have been renamed:
  2836 
  2837       subset_def   -> subset_eq
  2838       psubset_def  -> psubset_eq
  2839       set_diff_def -> set_diff_eq
  2840       Compl_def    -> Compl_eq
  2841       Sup_set_def  -> Sup_set_eq
  2842       Inf_set_def  -> Inf_set_eq
  2843       sup_set_def  -> sup_set_eq
  2844       inf_set_def  -> inf_set_eq
  2845 
  2846   - Due to the incompleteness of the HO unification algorithm, some
  2847     rules such as subst may require manual instantiation, if some of
  2848     the unknowns in the rule is a set.
  2849 
  2850   - Higher order unification and forward proofs:
  2851     The proof pattern
  2852 
  2853       have "P (S::'a set)" <...>
  2854       then have "EX S. P S" ..
  2855 
  2856     no longer works (due to the incompleteness of the HO unification
  2857     algorithm) and must be replaced by the pattern
  2858 
  2859       have "EX S. P S"
  2860       proof
  2861         show "P S" <...>
  2862       qed
  2863 
  2864   - Calculational reasoning with subst (or similar rules):
  2865     The proof pattern
  2866 
  2867       have "P (S::'a set)" <...>
  2868       also have "S = T" <...>
  2869       finally have "P T" .
  2870 
  2871     no longer works (for similar reasons as the previous example) and
  2872     must be replaced by something like
  2873 
  2874       have "P (S::'a set)" <...>
  2875       moreover have "S = T" <...>
  2876       ultimately have "P T" by simp
  2877 
  2878   - Tactics or packages written in ML code:
  2879     Code performing pattern matching on types via
  2880 
  2881       Type ("set", [T]) => ...
  2882 
  2883     must be rewritten. Moreover, functions like strip_type or
  2884     binder_types no longer return the right value when applied to a
  2885     type of the form
  2886 
  2887       T1 => ... => Tn => U => bool
  2888 
  2889     rather than
  2890 
  2891       T1 => ... => Tn => U set
  2892 
  2893 * Merged theories Wellfounded_Recursion, Accessible_Part and
  2894 Wellfounded_Relations to theory Wellfounded.
  2895 
  2896 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  2897 
  2898 * Class finite no longer treats UNIV as class parameter.  Use class
  2899 enum from theory Library/Enum instead to achieve a similar effect.
  2900 INCOMPATIBILITY.
  2901 
  2902 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  2903 and "Cons".  INCOMPATIBILITY.
  2904 
  2905 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  2906 Potential INCOMPATIBILITY.
  2907 
  2908 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  2909 injective_fst_snd removed, use split_eta and prod_eqI instead.
  2910 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  2911 
  2912 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  2913 the same name in theory Orderings:
  2914 
  2915   less_trans
  2916   less_linear
  2917   le_imp_less_or_eq
  2918   le_less_trans
  2919   less_le_trans
  2920   less_not_sym
  2921   less_asym
  2922 
  2923 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  2924 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  2925 and different variable names.
  2926 
  2927 * Library/Option_ord.thy: Canonical order on option type.
  2928 
  2929 * Library/RBT.thy: Red-black trees, an efficient implementation of
  2930 finite maps.
  2931 
  2932 * Library/Countable.thy: Type class for countable types.
  2933 
  2934 * Theory Int: The representation of numerals has changed.  The infix
  2935 operator BIT and the bit datatype with constructors B0 and B1 have
  2936 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  2937 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  2938 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  2939 accordingly.
  2940 
  2941 * Theory Nat: definition of <= and < on natural numbers no longer
  2942 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  2943 le_def and less_def have disappeared.  Consider lemmas not_less
  2944 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  2945 
  2946 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  2947 (whose purpose mainly is for various fold_set functionals) have been
  2948 abandoned in favor of the existing algebraic classes
  2949 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  2950 lower_semilattice (resp. upper_semilattice) and linorder.
  2951 INCOMPATIBILITY.
  2952 
  2953 * Theory Transitive_Closure: induct and cases rules now declare proper
  2954 case_names ("base" and "step").  INCOMPATIBILITY.
  2955 
  2956 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  2957 lattices.  The form set-specific version is available as
  2958 Inductive.lfp_ordinal_induct_set.
  2959 
  2960 * Renamed theorems "power.simps" to "power_int.simps".
  2961 INCOMPATIBILITY.
  2962 
  2963 * Class semiring_div provides basic abstract properties of semirings
  2964 with division and modulo operations.  Subsumes former class dvd_mod.
  2965 
  2966 * Merged theories IntDef, Numeral and IntArith into unified theory
  2967 Int.  INCOMPATIBILITY.
  2968 
  2969 * Theory Library/Code_Index: type "index" now represents natural
  2970 numbers rather than integers.  INCOMPATIBILITY.
  2971 
  2972 * New class "uminus" with operation "uminus" (split of from class
  2973 "minus" which now only has operation "minus", binary).
  2974 INCOMPATIBILITY.
  2975 
  2976 * Constants "card", "internal_split", "option_map" now with authentic
  2977 syntax.  INCOMPATIBILITY.
  2978 
  2979 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  2980 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  2981 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  2982 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  2983 Sup_set_def, le_def, less_def, option_map_def now with object
  2984 equality.  INCOMPATIBILITY.
  2985 
  2986 * Records. Removed K_record, and replaced it by pure lambda term
  2987 %x. c. The simplifier setup is now more robust against eta expansion.
  2988 INCOMPATIBILITY: in cases explicitly referring to K_record.
  2989 
  2990 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  2991 
  2992 * Library/ListVector: new theory of arithmetic vector operations.
  2993 
  2994 * Library/Order_Relation: new theory of various orderings as sets of
  2995 pairs.  Defines preorders, partial orders, linear orders and
  2996 well-orders on sets and on types.
  2997 
  2998 
  2999 *** ZF ***
  3000 
  3001 * Renamed some theories to allow to loading both ZF and HOL in the
  3002 same session:
  3003 
  3004   Datatype  -> Datatype_ZF
  3005   Inductive -> Inductive_ZF
  3006   Int       -> Int_ZF
  3007   IntDiv    -> IntDiv_ZF
  3008   Nat       -> Nat_ZF
  3009   List      -> List_ZF
  3010   Main      -> Main_ZF
  3011 
  3012 INCOMPATIBILITY: ZF theories that import individual theories below
  3013 Main might need to be adapted.  Regular theory Main is still
  3014 available, as trivial extension of Main_ZF.
  3015 
  3016 
  3017 *** ML ***
  3018 
  3019 * ML within Isar: antiquotation @{const name} or @{const
  3020 name(typargs)} produces statically-checked Const term.
  3021 
  3022 * Functor NamedThmsFun: data is available to the user as dynamic fact
  3023 (of the same name).  Removed obsolete print command.
  3024 
  3025 * Removed obsolete "use_legacy_bindings" function.
  3026 
  3027 * The ``print mode'' is now a thread-local value derived from a global
  3028 template (the former print_mode reference), thus access becomes
  3029 non-critical.  The global print_mode reference is for session
  3030 management only; user-code should use print_mode_value,
  3031 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  3032 
  3033 * Functions system/system_out provide a robust way to invoke external
  3034 shell commands, with propagation of interrupts (requires Poly/ML
  3035 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  3036 
  3037 
  3038 *** System ***
  3039 
  3040 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  3041 in accordance with Proof General 3.7, which prefers GNU emacs.
  3042 
  3043 * isatool tty runs Isabelle process with plain tty interaction;
  3044 optional line editor may be specified via ISABELLE_LINE_EDITOR
  3045 setting, the default settings attempt to locate "ledit" and "rlwrap".
  3046 
  3047 * isatool browser now works with Cygwin as well, using general
  3048 "javapath" function defined in Isabelle process environment.
  3049 
  3050 * YXML notation provides a simple and efficient alternative to
  3051 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  3052 isatool yxml as described in the Isabelle system manual.
  3053 
  3054 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  3055 provides general wrapper for managing an Isabelle process in a robust
  3056 fashion, with ``cooked'' output from stdin/stderr.
  3057 
  3058 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  3059 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  3060 
  3061 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  3062 way of changing the user's settings is via
  3063 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  3064 script.
  3065 
  3066 * Multithreading.max_threads := 0 refers to the number of actual CPU
  3067 cores of the underlying machine, which is a good starting point for
  3068 optimal performance tuning.  The corresponding usedir option -M allows
  3069 "max" as an alias for "0".  WARNING: does not work on certain versions
  3070 of Mac OS (with Poly/ML 5.1).
  3071 
  3072 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  3073 adverse effect of Isabelle flooding interactive front-ends (notably
  3074 ProofGeneral / XEmacs).
  3075 
  3076 
  3077 
  3078 New in Isabelle2007 (November 2007)
  3079 -----------------------------------
  3080 
  3081 *** General ***
  3082 
  3083 * More uniform information about legacy features, notably a
  3084 warning/error of "Legacy feature: ...", depending on the state of the
  3085 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  3086 legacy features will disappear eventually.
  3087 
  3088 * Theory syntax: the header format ``theory A = B + C:'' has been
  3089 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  3090 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  3091 
  3092 * Theory syntax: the old non-Isar theory file format has been
  3093 discontinued altogether.  Note that ML proof scripts may still be used
  3094 with Isar theories; migration is usually quite simple with the ML
  3095 function use_legacy_bindings.  INCOMPATIBILITY.
  3096 
  3097 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  3098 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  3099 quotes.
  3100 
  3101 * Theory loader: be more serious about observing the static theory
  3102 header specifications (including optional directories), but not the
  3103 accidental file locations of previously successful loads.  The strict
  3104 update policy of former update_thy is now already performed by
  3105 use_thy, so the former has been removed; use_thys updates several
  3106 theories simultaneously, just as 'imports' within a theory header
  3107 specification, but without merging the results.  Potential
  3108 INCOMPATIBILITY: may need to refine theory headers and commands
  3109 ROOT.ML which depend on load order.
  3110 
  3111 * Theory loader: optional support for content-based file
  3112 identification, instead of the traditional scheme of full physical
  3113 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  3114 (cf. the system manual).  The new scheme allows to work with
  3115 non-finished theories in persistent session images, such that source
  3116 files may be moved later on without requiring reloads.
  3117 
  3118 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3119 file (with the same base name as the theory) are considered a legacy
  3120 feature, which will disappear eventually. Even now, the theory loader
  3121 no longer maintains dependencies on such files.
  3122 
  3123 * Syntax: the scope for resolving ambiguities via type-inference is
  3124 now limited to individual terms, instead of whole simultaneous
  3125 specifications as before. This greatly reduces the complexity of the
  3126 syntax module and improves flexibility by separating parsing and
  3127 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  3128 'fixes' etc.) are required in rare situations.
  3129 
  3130 * Syntax: constants introduced by new-style packages ('definition',
  3131 'abbreviation' etc.) are passed through the syntax module in
  3132 ``authentic mode''. This means that associated mixfix annotations
  3133 really stick to such constants, independently of potential name space
  3134 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  3135 trees are represented slightly differently, may need to adapt syntax
  3136 translations accordingly. Use CONST marker in 'translations' and
  3137 @{const_syntax} antiquotation in 'parse_translation' etc.
  3138 
  3139 * Legacy goal package: reduced interface to the bare minimum required
  3140 to keep existing proof scripts running.  Most other user-level
  3141 functions are now part of the OldGoals structure, which is *not* open
  3142 by default (consider isatool expandshort before open OldGoals).
  3143 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  3144 these tend to cause confusion about the actual goal (!) context being
  3145 used here, which is not necessarily the same as the_context().
  3146 
  3147 * Command 'find_theorems': supports "*" wild-card in "name:"
  3148 criterion; "with_dups" option.  Certain ProofGeneral versions might
  3149 support a specific search form (see ProofGeneral/CHANGES).
  3150 
  3151 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  3152 by default, which means that "prems" (and also "fixed variables") are
  3153 suppressed from proof state output.  Note that the ProofGeneral
  3154 settings mechanism allows to change and save options persistently, but
  3155 older versions of Isabelle will fail to start up if a negative prems
  3156 limit is imposed.
  3157 
  3158 * Local theory targets may be specified by non-nested blocks of
  3159 ``context/locale/class ... begin'' followed by ``end''.  The body may
  3160 contain definitions, theorems etc., including any derived mechanism
  3161 that has been implemented on top of these primitives.  This concept
  3162 generalizes the existing ``theorem (in ...)'' towards more versatility
  3163 and scalability.
  3164 
  3165 * Proof General interface: proper undo of final 'end' command;
  3166 discontinued Isabelle/classic mode (ML proof scripts).
  3167 
  3168 
  3169 *** Document preparation ***
  3170 
  3171 * Added antiquotation @{theory name} which prints the given name,
  3172 after checking that it refers to a valid ancestor theory in the
  3173 current context.
  3174 
  3175 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  3176 check the given source text as ML type/structure, printing verbatim.
  3177 
  3178 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  3179 "c args == rhs" given in the current context.  (Any number of
  3180 arguments may be given on the LHS.)
  3181 
  3182 
  3183 *** Pure ***
  3184 
  3185 * The 'class' package offers a combination of axclass and locale to
  3186 achieve Haskell-like type classes in Isabelle.  Definitions and
  3187 theorems within a class context produce both relative results (with
  3188 implicit parameters according to the locale context), and polymorphic
  3189 constants with qualified polymorphism (according to the class
  3190 context).  Within the body context of a 'class' target, a separate
  3191 syntax layer ("user space type system") takes care of converting
  3192 between global polymorphic consts and internal locale representation.
  3193 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  3194 "isatool doc classes" provides a tutorial.
  3195 
  3196 * Generic code generator framework allows to generate executable
  3197 code for ML and Haskell (including Isabelle classes).  A short usage
  3198 sketch:
  3199 
  3200     internal compilation:
  3201         export_code <list of constants (term syntax)> in SML
  3202     writing SML code to a file:
  3203         export_code <list of constants (term syntax)> in SML <filename>
  3204     writing OCaml code to a file:
  3205         export_code <list of constants (term syntax)> in OCaml <filename>
  3206     writing Haskell code to a bunch of files:
  3207         export_code <list of constants (term syntax)> in Haskell <filename>
  3208 
  3209     evaluating closed propositions to True/False using code generation:
  3210         method ``eval''
  3211 
  3212 Reasonable default setup of framework in HOL.
  3213 
  3214 Theorem attributs for selecting and transforming function equations theorems:
  3215 
  3216     [code fun]:        select a theorem as function equation for a specific constant
  3217     [code fun del]:    deselect a theorem as function equation for a specific constant
  3218     [code inline]:     select an equation theorem for unfolding (inlining) in place
  3219     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  3220 
  3221 User-defined serializations (target in {SML, OCaml, Haskell}):
  3222 
  3223     code_const <and-list of constants (term syntax)>
  3224       {(target) <and-list of const target syntax>}+
  3225 
  3226     code_type <and-list of type constructors>
  3227       {(target) <and-list of type target syntax>}+
  3228 
  3229     code_instance <and-list of instances>
  3230       {(target)}+
  3231         where instance ::= <type constructor> :: <class>
  3232 
  3233     code_class <and_list of classes>
  3234       {(target) <and-list of class target syntax>}+
  3235         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  3236 
  3237 code_instance and code_class only are effective to target Haskell.
  3238 
  3239 For example usage see src/HOL/ex/Codegenerator.thy and
  3240 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  3241 generation from Isabelle/HOL theories is available via "isatool doc
  3242 codegen".
  3243 
  3244 * Code generator: consts in 'consts_code' Isar commands are now
  3245 referred to by usual term syntax (including optional type
  3246 annotations).
  3247 
  3248 * Command 'no_translations' removes translation rules from theory
  3249 syntax.
  3250 
  3251 * Overloaded definitions are now actually checked for acyclic
  3252 dependencies.  The overloading scheme is slightly more general than
  3253 that of Haskell98, although Isabelle does not demand an exact
  3254 correspondence to type class and instance declarations.
  3255 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  3256 exotic versions of overloading -- at the discretion of the user!
  3257 
  3258 Polymorphic constants are represented via type arguments, i.e. the
  3259 instantiation that matches an instance against the most general
  3260 declaration given in the signature.  For example, with the declaration
  3261 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  3262 as c(nat).  Overloading is essentially simultaneous structural
  3263 recursion over such type arguments.  Incomplete specification patterns
  3264 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  3265 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  3266 Command 'print_theory' outputs the normalized system of recursive
  3267 equations, see section "definitions".
  3268 
  3269 * Configuration options are maintained within the theory or proof
  3270 context (with name and type bool/int/string), providing a very simple
  3271 interface to a poor-man's version of general context data.  Tools may
  3272 declare options in ML (e.g. using Attrib.config_int) and then refer to
  3273 these values using Config.get etc.  Users may change options via an
  3274 associated attribute of the same name.  This form of context
  3275 declaration works particularly well with commands 'declare' or
  3276 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  3277 very easy to avoid global references, which would not observe Isar
  3278 toplevel undo/redo and fail to work with multithreading.
  3279 
  3280 Various global ML references of Pure and HOL have been turned into
  3281 configuration options:
  3282 
  3283   Unify.search_bound		unify_search_bound
  3284   Unify.trace_bound		unify_trace_bound
  3285   Unify.trace_simp		unify_trace_simp
  3286   Unify.trace_types		unify_trace_types
  3287   Simplifier.simp_depth_limit	simp_depth_limit
  3288   Blast.depth_limit		blast_depth_limit
  3289   DatatypeProp.dtK		datatype_distinctness_limit
  3290   fast_arith_neq_limit  	fast_arith_neq_limit
  3291   fast_arith_split_limit	fast_arith_split_limit
  3292 
  3293 * Named collections of theorems may be easily installed as context
  3294 data using the functor NamedThmsFun (see also
  3295 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  3296 attributes; there is also a toplevel print command.  This facility is
  3297 just a common case of general context data, which is the preferred way
  3298 for anything more complex than just a list of facts in canonical
  3299 order.
  3300 
  3301 * Isar: command 'declaration' augments a local theory by generic
  3302 declaration functions written in ML.  This enables arbitrary content
  3303 being added to the context, depending on a morphism that tells the
  3304 difference of the original declaration context wrt. the application
  3305 context encountered later on.
  3306 
  3307 * Isar: proper interfaces for simplification procedures.  Command
  3308 'simproc_setup' declares named simprocs (with match patterns, and body
  3309 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  3310 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  3311 
  3312 * Isar: an extra pair of brackets around attribute declarations
  3313 abbreviates a theorem reference involving an internal dummy fact,
  3314 which will be ignored later --- only the effect of the attribute on
  3315 the background context will persist.  This form of in-place
  3316 declarations is particularly useful with commands like 'declare' and
  3317 'using', for example ``have A using [[simproc a]] by simp''.
  3318 
  3319 * Isar: method "assumption" (and implicit closing of subproofs) now
  3320 takes simple non-atomic goal assumptions into account: after applying
  3321 an assumption as a rule the resulting subgoals are solved by atomic
  3322 assumption steps.  This is particularly useful to finish 'obtain'
  3323 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  3324 without referring to the original premise "!!x. P x ==> thesis" in the
  3325 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  3326 more permissive.
  3327 
  3328 * Isar: implicit use of prems from the Isar proof context is
  3329 considered a legacy feature.  Common applications like ``have A .''
  3330 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  3331 referencing facts explicitly here improves readability and
  3332 maintainability of proof texts.
  3333 
  3334 * Isar: improper proof element 'guess' is like 'obtain', but derives
  3335 the obtained context from the course of reasoning!  For example:
  3336 
  3337   assume "EX x y. A x & B y"   -- "any previous fact"
  3338   then guess x and y by clarify
  3339 
  3340 This technique is potentially adventurous, depending on the facts and
  3341 proof tools being involved here.
  3342 
  3343 * Isar: known facts from the proof context may be specified as literal
  3344 propositions, using ASCII back-quote syntax.  This works wherever
  3345 named facts used to be allowed so far, in proof commands, proof
  3346 methods, attributes etc.  Literal facts are retrieved from the context
  3347 according to unification of type and term parameters.  For example,
  3348 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  3349 theorems in the current context, then these are valid literal facts:
  3350 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  3351 
  3352 There is also a proof method "fact" which does the same composition
  3353 for explicit goal states, e.g. the following proof texts coincide with
  3354 certain special cases of literal facts:
  3355 
  3356   have "A" by fact                 ==  note `A`
  3357   have "A ==> B" by fact           ==  note `A ==> B`
  3358   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  3359   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  3360 
  3361 * Isar: ":" (colon) is no longer a symbolic identifier character in
  3362 outer syntax.  Thus symbolic identifiers may be used without
  3363 additional white space in declarations like this: ``assume *: A''.
  3364 
  3365 * Isar: 'print_facts' prints all local facts of the current context,
  3366 both named and unnamed ones.
  3367 
  3368 * Isar: 'def' now admits simultaneous definitions, e.g.:
  3369 
  3370   def x == "t" and y == "u"
  3371 
  3372 * Isar: added command 'unfolding', which is structurally similar to
  3373 'using', but affects both the goal state and facts by unfolding given
  3374 rewrite rules.  Thus many occurrences of the 'unfold' method or
  3375 'unfolded' attribute may be replaced by first-class proof text.
  3376 
  3377 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  3378 and command 'unfolding' now all support object-level equalities
  3379 (potentially conditional).  The underlying notion of rewrite rule is
  3380 analogous to the 'rule_format' attribute, but *not* that of the
  3381 Simplifier (which is usually more generous).
  3382 
  3383 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  3384 premises of a theorem by n. Useful in conjunction with drule.
  3385 
  3386 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  3387 method expression within a sandbox consisting of the first N
  3388 sub-goals, which need to exist.  For example, ``simp_all [3]''
  3389 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  3390 simplifies all new goals that emerge from applying rule foo to the
  3391 originally first one.
  3392 
  3393 * Isar: schematic goals are no longer restricted to higher-order
  3394 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  3395 expected.
  3396 
  3397 * Isar: the conclusion of a long theorem statement is now either
  3398 'shows' (a simultaneous conjunction, as before), or 'obtains'
  3399 (essentially a disjunction of cases with local parameters and
  3400 assumptions).  The latter allows to express general elimination rules
  3401 adequately; in this notation common elimination rules look like this:
  3402 
  3403   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  3404     assumes "EX x. P x"
  3405     obtains x where "P x"
  3406 
  3407   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  3408     assumes "A & B"
  3409     obtains A and B
  3410 
  3411   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  3412     assumes "A | B"
  3413     obtains
  3414       A
  3415     | B
  3416 
  3417 The subsequent classical rules even refer to the formal "thesis"
  3418 explicitly:
  3419 
  3420   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  3421     obtains "~ thesis"
  3422 
  3423   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  3424     obtains "thesis ==> something"
  3425 
  3426 The actual proof of an 'obtains' statement is analogous to that of the
  3427 Isar proof element 'obtain', only that there may be several cases.
  3428 Optional case names may be specified in parentheses; these will be
  3429 available both in the present proof and as annotations in the
  3430 resulting rule, for later use with the 'cases' method (cf. attribute
  3431 case_names).
  3432 
  3433 * Isar: the assumptions of a long theorem statement are available as
  3434 "assms" fact in the proof context.  This is more appropriate than the
  3435 (historical) "prems", which refers to all assumptions of the current
  3436 context, including those from the target locale, proof body etc.
  3437 
  3438 * Isar: 'print_statement' prints theorems from the current theory or
  3439 proof context in long statement form, according to the syntax of a
  3440 top-level lemma.
  3441 
  3442 * Isar: 'obtain' takes an optional case name for the local context
  3443 introduction rule (default "that").
  3444 
  3445 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  3446 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  3447 to occur.
  3448 
  3449 * Pure: syntax "CONST name" produces a fully internalized constant
  3450 according to the current context.  This is particularly useful for
  3451 syntax translations that should refer to internal constant
  3452 representations independently of name spaces.
  3453 
  3454 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  3455 instead of "FOO ". This allows multiple binder declarations to coexist
  3456 in the same context.  INCOMPATIBILITY.
  3457 
  3458 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  3459 primitive that also works in a locale context (both for constants and
  3460 fixed variables). Type declaration and internal syntactic representation
  3461 of given constants retrieved from the context. Likewise, the
  3462 'no_notation' command allows to remove given syntax annotations from the
  3463 current context.
  3464 
  3465 * Isar/locales: new derived specification elements 'axiomatization',
  3466 'definition', 'abbreviation', which support type-inference, admit
  3467 object-level specifications (equality, equivalence).  See also the
  3468 isar-ref manual.  Examples:
  3469 
  3470   axiomatization
  3471     eq  (infix "===" 50) where
  3472     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  3473 
  3474   definition "f x y = x + y + 1"
  3475   definition g where "g x = f x x"
  3476 
  3477   abbreviation
  3478     neq  (infix "=!=" 50) where
  3479     "x =!= y == ~ (x === y)"
  3480 
  3481 These specifications may be also used in a locale context.  Then the
  3482 constants being introduced depend on certain fixed parameters, and the
  3483 constant name is qualified by the locale base name.  An internal
  3484 abbreviation takes care for convenient input and output, making the
  3485 parameters implicit and using the original short name.  See also
  3486 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  3487 entities from a monomorphic theory.
  3488 
  3489 Presently, abbreviations are only available 'in' a target locale, but
  3490 not inherited by general import expressions.  Also note that
  3491 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  3492 'translations' in common applications.  The "no_abbrevs" print mode
  3493 prevents folding of abbreviations in term output.
  3494 
  3495 Concrete syntax is attached to specified constants in internal form,
  3496 independently of name spaces.  The parse tree representation is
  3497 slightly different -- use 'notation' instead of raw 'syntax', and
  3498 'translations' with explicit "CONST" markup to accommodate this.
  3499 
  3500 * Pure/Isar: unified syntax for new-style specification mechanisms
  3501 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  3502 full type inference and dummy patterns ("_").  For example:
  3503 
  3504   definition "K x _ = x"
  3505 
  3506   inductive conj for A B
  3507   where "A ==> B ==> conj A B"
  3508 
  3509 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  3510 the current context.  Print mode "no_abbrevs" prevents inversion of
  3511 abbreviations on output.
  3512 
  3513 * Isar/locales: improved parameter handling: use of locales "var" and
  3514 "struct" no longer necessary; - parameter renamings are no longer
  3515 required to be injective.  For example, this allows to define
  3516 endomorphisms as locale endom = homom mult mult h.
  3517 
  3518 * Isar/locales: changed the way locales with predicates are defined.
  3519 Instead of accumulating the specification, the imported expression is
  3520 now an interpretation.  INCOMPATIBILITY: different normal form of
  3521 locale expressions.  In particular, in interpretations of locales with
  3522 predicates, goals repesenting already interpreted fragments are not
  3523 removed automatically.  Use methods `intro_locales' and
  3524 `unfold_locales'; see below.
  3525 
  3526 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  3527 provide backward reasoning on locales predicates.  The methods are
  3528 aware of interpretations and discharge corresponding goals.
  3529 `intro_locales' is less aggressive then `unfold_locales' and does not
  3530 unfold predicates to assumptions.
  3531 
  3532 * Isar/locales: the order in which locale fragments are accumulated
  3533 has changed.  This enables to override declarations from fragments due
  3534 to interpretations -- for example, unwanted simp rules.
  3535 
  3536 * Isar/locales: interpretation in theories and proof contexts has been
  3537 extended.  One may now specify (and prove) equations, which are
  3538 unfolded in interpreted theorems.  This is useful for replacing
  3539 defined concepts (constants depending on locale parameters) by
  3540 concepts already existing in the target context.  Example:
  3541 
  3542   interpretation partial_order ["op <= :: [int, int] => bool"]
  3543     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3544 
  3545 Typically, the constant `partial_order.less' is created by a
  3546 definition specification element in the context of locale
  3547 partial_order.
  3548 
  3549 * Method "induct": improved internal context management to support
  3550 local fixes and defines on-the-fly. Thus explicit meta-level
  3551 connectives !!  and ==> are rarely required anymore in inductive goals
  3552 (using object-logic connectives for this purpose has been long
  3553 obsolete anyway). Common proof patterns are explained in
  3554 src/HOL/Induct/Common_Patterns.thy, see also
  3555 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3556 examples.
  3557 
  3558 * Method "induct": improved handling of simultaneous goals. Instead of
  3559 introducing object-level conjunction, the statement is now split into
  3560 several conclusions, while the corresponding symbolic cases are nested
  3561 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3562 see src/HOL/Induct/Common_Patterns.thy, for example.
  3563 
  3564 * Method "induct": mutual induction rules are now specified as a list
  3565 of rule sharing the same induction cases. HOL packages usually provide
  3566 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3567 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3568 mutual induction rules differently, i.e. like this:
  3569 
  3570   (induct rule: foo_bar.inducts)
  3571   (induct set: foo bar)
  3572   (induct pred: foo bar)
  3573   (induct type: foo bar)
  3574 
  3575 The ML function ProjectRule.projections turns old-style rules into the
  3576 new format.
  3577 
  3578 * Method "coinduct": dual of induction, see
  3579 src/HOL/Library/Coinductive_List.thy for various examples.
  3580 
  3581 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3582 considered a legacy feature.
  3583 
  3584 * Attribute "symmetric" produces result with standardized schematic
  3585 variables (index 0).  Potential INCOMPATIBILITY.
  3586 
  3587 * Simplifier: by default the simplifier trace only shows top level
  3588 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3589 default. Thus there is less danger of being flooded by the trace. The
  3590 trace indicates where parts have been suppressed.
  3591   
  3592 * Provers/classical: removed obsolete classical version of elim_format
  3593 attribute; classical elim/dest rules are now treated uniformly when
  3594 manipulating the claset.
  3595 
  3596 * Provers/classical: stricter checks to ensure that supplied intro,
  3597 dest and elim rules are well-formed; dest and elim rules must have at
  3598 least one premise.
  3599 
  3600 * Provers/classical: attributes dest/elim/intro take an optional
  3601 weight argument for the rule (just as the Pure versions).  Weights are
  3602 ignored by automated tools, but determine the search order of single
  3603 rule steps.
  3604 
  3605 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3606 where the body does not mention the bound variable.  Note that dummy
  3607 patterns implicitly depend on their context of bounds, which makes
  3608 "{_. _}" match any set comprehension as expected.  Potential
  3609 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3610 constant "_idtdummy" in the binding position.
  3611 
  3612 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3613 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3614 for example "A -> B" => "Pi A (%_. B)".
  3615 
  3616 * Pure: 'class_deps' command visualizes the subclass relation, using
  3617 the graph browser tool.
  3618 
  3619 * Pure: 'print_theory' now suppresses certain internal declarations by
  3620 default; use '!' option for full details.
  3621 
  3622 
  3623 *** HOL ***
  3624 
  3625 * Method "metis" proves goals by applying the Metis general-purpose
  3626 resolution prover (see also http://gilith.com/software/metis/).
  3627 Examples are in the directory MetisExamples.  WARNING: the
  3628 Isabelle/HOL-Metis integration does not yet work properly with
  3629 multi-threading.
  3630   
  3631 * Command 'sledgehammer' invokes external automatic theorem provers as
  3632 background processes.  It generates calls to the "metis" method if
  3633 successful. These can be pasted into the proof.  Users do not have to
  3634 wait for the automatic provers to return.  WARNING: does not really
  3635 work with multi-threading.
  3636 
  3637 * New "auto_quickcheck" feature tests outermost goal statements for
  3638 potential counter-examples.  Controlled by ML references
  3639 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3640 5000 milliseconds).  Fails silently if statements is outside of
  3641 executable fragment, or any other codgenerator problem occurs.
  3642 
  3643 * New constant "undefined" with axiom "undefined x = undefined".
  3644 
  3645 * Added class "HOL.eq", allowing for code generation with polymorphic
  3646 equality.
  3647 
  3648 * Some renaming of class constants due to canonical name prefixing in
  3649 the new 'class' package:
  3650 
  3651     HOL.abs ~> HOL.abs_class.abs
  3652     HOL.divide ~> HOL.divide_class.divide
  3653     0 ~> HOL.zero_class.zero
  3654     1 ~> HOL.one_class.one
  3655     op + ~> HOL.plus_class.plus
  3656     op - ~> HOL.minus_class.minus
  3657     uminus ~> HOL.minus_class.uminus
  3658     op * ~> HOL.times_class.times
  3659     op < ~> HOL.ord_class.less
  3660     op <= > HOL.ord_class.less_eq
  3661     Nat.power ~> Power.power_class.power
  3662     Nat.size ~> Nat.size_class.size
  3663     Numeral.number_of ~> Numeral.number_class.number_of
  3664     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3665     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3666     Orderings.min ~> Orderings.ord_class.min
  3667     Orderings.max ~> Orderings.ord_class.max
  3668     Divides.op div ~> Divides.div_class.div
  3669     Divides.op mod ~> Divides.div_class.mod
  3670     Divides.op dvd ~> Divides.div_class.dvd
  3671 
  3672 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3673 
  3674 a) User-defined constants using any of the names "plus", "minus",
  3675 "times", "less" or "less_eq". The standard syntax translations for
  3676 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3677 names.
  3678 
  3679 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3680 INCOMPATIBILITY: use more specific names.
  3681 
  3682 c) Permutative equations (e.g. "a + b = b + a")
  3683 Since the change of names also changes the order of terms, permutative
  3684 rewrite rules may get applied in a different order. Experience shows
  3685 that this is rarely the case (only two adaptions in the whole Isabelle
  3686 distribution).  INCOMPATIBILITY: rewrite proofs
  3687 
  3688 d) ML code directly refering to constant names
  3689 This in general only affects hand-written proof tactics, simprocs and
  3690 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3691 Consider using @{const_name} antiquotation.
  3692 
  3693 * New class "default" with associated constant "default".
  3694 
  3695 * Function "sgn" is now overloaded and available on int, real, complex
  3696 (and other numeric types), using class "sgn".  Two possible defs of
  3697 sgn are given as equational assumptions in the classes sgn_if and
  3698 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3699 INCOMPATIBILITY.
  3700 
  3701 * Locale "partial_order" now unified with class "order" (cf. theory
  3702 Orderings), added parameter "less".  INCOMPATIBILITY.
  3703 
  3704 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3705 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3706 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3707 
  3708 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3709 changed order of proof goals in instance proofs.
  3710 
  3711 * The transitivity reasoner for partial and linear orders is set up
  3712 for classes "order" and "linorder".  Instances of the reasoner are available
  3713 in all contexts importing or interpreting the corresponding locales.
  3714 Method "order" invokes the reasoner separately; the reasoner
  3715 is also integrated with the Simplifier as a solver.  Diagnostic
  3716 command 'print_orders' shows the available instances of the reasoner
  3717 in the current context.
  3718 
  3719 * Localized monotonicity predicate in theory "Orderings"; integrated
  3720 lemmas max_of_mono and min_of_mono with this predicate.
  3721 INCOMPATIBILITY.
  3722 
  3723 * Formulation of theorem "dense" changed slightly due to integration
  3724 with new class dense_linear_order.
  3725 
  3726 * Uniform lattice theory development in HOL.
  3727 
  3728     constants "meet" and "join" now named "inf" and "sup"
  3729     constant "Meet" now named "Inf"
  3730 
  3731     classes "meet_semilorder" and "join_semilorder" now named
  3732       "lower_semilattice" and "upper_semilattice"
  3733     class "lorder" now named "lattice"
  3734     class "comp_lat" now named "complete_lattice"
  3735 
  3736     Instantiation of lattice classes allows explicit definitions
  3737     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3738 
  3739   INCOMPATIBILITY.  Theorem renames:
  3740 
  3741     meet_left_le            ~> inf_le1
  3742     meet_right_le           ~> inf_le2
  3743     join_left_le            ~> sup_ge1
  3744     join_right_le           ~> sup_ge2
  3745     meet_join_le            ~> inf_sup_ord
  3746     le_meetI                ~> le_infI
  3747     join_leI                ~> le_supI
  3748     le_meet                 ~> le_inf_iff
  3749     le_join                 ~> ge_sup_conv
  3750     meet_idempotent         ~> inf_idem
  3751     join_idempotent         ~> sup_idem
  3752     meet_comm               ~> inf_commute
  3753     join_comm               ~> sup_commute
  3754     meet_leI1               ~> le_infI1
  3755     meet_leI2               ~> le_infI2
  3756     le_joinI1               ~> le_supI1
  3757     le_joinI2               ~> le_supI2
  3758     meet_assoc              ~> inf_assoc
  3759     join_assoc              ~> sup_assoc
  3760     meet_left_comm          ~> inf_left_commute
  3761     meet_left_idempotent    ~> inf_left_idem
  3762     join_left_comm          ~> sup_left_commute
  3763     join_left_idempotent    ~> sup_left_idem
  3764     meet_aci                ~> inf_aci
  3765     join_aci                ~> sup_aci
  3766     le_def_meet             ~> le_iff_inf
  3767     le_def_join             ~> le_iff_sup
  3768     join_absorp2            ~> sup_absorb2
  3769     join_absorp1            ~> sup_absorb1
  3770     meet_absorp1            ~> inf_absorb1
  3771     meet_absorp2            ~> inf_absorb2
  3772     meet_join_absorp        ~> inf_sup_absorb
  3773     join_meet_absorp        ~> sup_inf_absorb
  3774     distrib_join_le         ~> distrib_sup_le
  3775     distrib_meet_le         ~> distrib_inf_le
  3776 
  3777     add_meet_distrib_left   ~> add_inf_distrib_left
  3778     add_join_distrib_left   ~> add_sup_distrib_left
  3779     is_join_neg_meet        ~> is_join_neg_inf
  3780     is_meet_neg_join        ~> is_meet_neg_sup
  3781     add_meet_distrib_right  ~> add_inf_distrib_right
  3782     add_join_distrib_right  ~> add_sup_distrib_right
  3783     add_meet_join_distribs  ~> add_sup_inf_distribs
  3784     join_eq_neg_meet        ~> sup_eq_neg_inf
  3785     meet_eq_neg_join        ~> inf_eq_neg_sup
  3786     add_eq_meet_join        ~> add_eq_inf_sup
  3787     meet_0_imp_0            ~> inf_0_imp_0
  3788     join_0_imp_0            ~> sup_0_imp_0
  3789     meet_0_eq_0             ~> inf_0_eq_0
  3790     join_0_eq_0             ~> sup_0_eq_0
  3791     neg_meet_eq_join        ~> neg_inf_eq_sup
  3792     neg_join_eq_meet        ~> neg_sup_eq_inf
  3793     join_eq_if              ~> sup_eq_if
  3794 
  3795     mono_meet               ~> mono_inf
  3796     mono_join               ~> mono_sup
  3797     meet_bool_eq            ~> inf_bool_eq
  3798     join_bool_eq            ~> sup_bool_eq
  3799     meet_fun_eq             ~> inf_fun_eq
  3800     join_fun_eq             ~> sup_fun_eq
  3801     meet_set_eq             ~> inf_set_eq
  3802     join_set_eq             ~> sup_set_eq
  3803     meet1_iff               ~> inf1_iff
  3804     meet2_iff               ~> inf2_iff
  3805     meet1I                  ~> inf1I
  3806     meet2I                  ~> inf2I
  3807     meet1D1                 ~> inf1D1
  3808     meet2D1                 ~> inf2D1
  3809     meet1D2                 ~> inf1D2
  3810     meet2D2                 ~> inf2D2
  3811     meet1E                  ~> inf1E
  3812     meet2E                  ~> inf2E
  3813     join1_iff               ~> sup1_iff
  3814     join2_iff               ~> sup2_iff
  3815     join1I1                 ~> sup1I1
  3816     join2I1                 ~> sup2I1
  3817     join1I1                 ~> sup1I1
  3818     join2I2                 ~> sup1I2
  3819     join1CI                 ~> sup1CI
  3820     join2CI                 ~> sup2CI
  3821     join1E                  ~> sup1E
  3822     join2E                  ~> sup2E
  3823 
  3824     is_meet_Meet            ~> is_meet_Inf
  3825     Meet_bool_def           ~> Inf_bool_def
  3826     Meet_fun_def            ~> Inf_fun_def
  3827     Meet_greatest           ~> Inf_greatest
  3828     Meet_lower              ~> Inf_lower
  3829     Meet_set_def            ~> Inf_set_def
  3830 
  3831     Sup_def                 ~> Sup_Inf
  3832     Sup_bool_eq             ~> Sup_bool_def
  3833     Sup_fun_eq              ~> Sup_fun_def
  3834     Sup_set_eq              ~> Sup_set_def
  3835 
  3836     listsp_meetI            ~> listsp_infI
  3837     listsp_meet_eq          ~> listsp_inf_eq
  3838 
  3839     meet_min                ~> inf_min
  3840     join_max                ~> sup_max
  3841 
  3842 * Added syntactic class "size"; overloaded constant "size" now has
  3843 type "'a::size ==> bool"
  3844 
  3845 * Internal reorganisation of `size' of datatypes: size theorems
  3846 "foo.size" are no longer subsumed by "foo.simps" (but are still
  3847 simplification rules by default!); theorems "prod.size" now named
  3848 "*.size".
  3849 
  3850 * Class "div" now inherits from class "times" rather than "type".
  3851 INCOMPATIBILITY.
  3852 
  3853 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  3854 Linorder etc.  have disappeared; operations defined in terms of
  3855 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  3856 
  3857 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  3858 
  3859 * HOL-Word: New extensive library and type for generic, fixed size
  3860 machine words, with arithemtic, bit-wise, shifting and rotating
  3861 operations, reflection into int, nat, and bool lists, automation for
  3862 linear arithmetic (by automatic reflection into nat or int), including
  3863 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  3864 arithmetic type classes, supporting automatic simplification of
  3865 numerals on all operations.
  3866 
  3867 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  3868 
  3869 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  3870 
  3871 * Code generator library theories:
  3872   - Code_Integer represents HOL integers by big integer literals in target
  3873     languages.
  3874   - Code_Char represents HOL characters by character literals in target
  3875     languages.
  3876   - Code_Char_chr like Code_Char, but also offers treatment of character
  3877     codes; includes Code_Integer.
  3878   - Executable_Set allows to generate code for finite sets using lists.
  3879   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  3880     denominator).
  3881   - Executable_Real implements a subset of real numbers, namly those
  3882     representable by rational numbers.
  3883   - Efficient_Nat implements natural numbers by integers, which in general will
  3884     result in higher efficency; pattern matching with 0/Suc is eliminated;
  3885     includes Code_Integer.
  3886   - Code_Index provides an additional datatype index which is mapped to
  3887     target-language built-in integers.
  3888   - Code_Message provides an additional datatype message_string which is isomorphic to
  3889     strings; messages are mapped to target-language strings.
  3890 
  3891 * New package for inductive predicates
  3892 
  3893   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  3894 
  3895     inductive
  3896       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3897       for z_1 :: U_1 and ... and z_n :: U_m
  3898     where
  3899       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3900     | ...
  3901 
  3902   with full support for type-inference, rather than
  3903 
  3904     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3905 
  3906     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3907     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3908 
  3909     inductive "s z_1 ... z_m"
  3910     intros
  3911       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3912       ...
  3913 
  3914   For backward compatibility, there is a wrapper allowing inductive
  3915   sets to be defined with the new package via
  3916 
  3917     inductive_set
  3918       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3919       for z_1 :: U_1 and ... and z_n :: U_m
  3920     where
  3921       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3922     | ...
  3923 
  3924   or
  3925 
  3926     inductive_set
  3927       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3928       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3929       for z_1 :: U_1 and ... and z_n :: U_m
  3930     where
  3931       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3932     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3933     | ...
  3934 
  3935   if the additional syntax "p ..." is required.
  3936 
  3937   Numerous examples can be found in the subdirectories src/HOL/Auth,
  3938   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  3939 
  3940   INCOMPATIBILITIES:
  3941 
  3942   - Since declaration and definition of inductive sets or predicates
  3943     is no longer separated, abbreviations involving the newly
  3944     introduced sets or predicates must be specified together with the
  3945     introduction rules after the 'where' keyword (see above), rather
  3946     than before the actual inductive definition.
  3947 
  3948   - The variables in induction and elimination rules are now
  3949     quantified in the order of their occurrence in the introduction
  3950     rules, rather than in alphabetical order. Since this may break
  3951     some proofs, these proofs either have to be repaired, e.g. by
  3952     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  3953     statements of the form
  3954 
  3955       case (rule_i a_i_1 ... a_i_{k_i})
  3956 
  3957     or the old order of quantification has to be restored by explicitly adding
  3958     meta-level quantifiers in the introduction rules, i.e.
  3959 
  3960       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  3961 
  3962   - The format of the elimination rules is now
  3963 
  3964       p z_1 ... z_m x_1 ... x_n ==>
  3965         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  3966         ==> ... ==> P
  3967 
  3968     for predicates and
  3969 
  3970       (x_1, ..., x_n) : s z_1 ... z_m ==>
  3971         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  3972         ==> ... ==> P
  3973 
  3974     for sets rather than
  3975 
  3976       x : s z_1 ... z_m ==>
  3977         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  3978         ==> ... ==> P
  3979 
  3980     This may require terms in goals to be expanded to n-tuples
  3981     (e.g. using case_tac or simplification with the split_paired_all
  3982     rule) before the above elimination rule is applicable.
  3983 
  3984   - The elimination or case analysis rules for (mutually) inductive
  3985     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  3986     list of rules "p_1_..._p_k.elims" is no longer available.
  3987 
  3988 * New package "function"/"fun" for general recursive functions,
  3989 supporting mutual and nested recursion, definitions in local contexts,
  3990 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  3991 for small examples, and the separate tutorial on the function
  3992 package. The old recdef "package" is still available as before, but
  3993 users are encouraged to use the new package.
  3994 
  3995 * Method "lexicographic_order" automatically synthesizes termination
  3996 relations as lexicographic combinations of size measures. 
  3997 
  3998 * Case-expressions allow arbitrary constructor-patterns (including
  3999 "_") and take their order into account, like in functional
  4000 programming.  Internally, this is translated into nested
  4001 case-expressions; missing cases are added and mapped to the predefined
  4002 constant "undefined". In complicated cases printing may no longer show
  4003 the original input but the internal form. Lambda-abstractions allow
  4004 the same form of pattern matching: "% pat1 => e1 | ..." is an
  4005 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  4006 variable.
  4007 
  4008 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  4009 is an abbreviation for "of_nat :: nat => int". The simplification
  4010 rules for "of_nat" have been changed to work like "int" did
  4011 previously.  Potential INCOMPATIBILITY:
  4012   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  4013   - of_nat_diff and of_nat_mult are no longer default simp rules
  4014 
  4015 * Method "algebra" solves polynomial equations over (semi)rings using
  4016 Groebner bases. The (semi)ring structure is defined by locales and the
  4017 tool setup depends on that generic context. Installing the method for
  4018 a specific type involves instantiating the locale and possibly adding
  4019 declarations for computation on the coefficients.  The method is
  4020 already instantiated for natural numbers and for the axiomatic class
  4021 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  4022 CALCULEMUS 2007 for the general principles underlying this
  4023 architecture of context-aware proof-tools.
  4024 
  4025 * Method "ferrack" implements quantifier elimination over
  4026 special-purpose dense linear orders using locales (analogous to
  4027 "algebra"). The method is already installed for class
  4028 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  4029 rat, etc.
  4030 
  4031 * Former constant "List.op @" now named "List.append".  Use ML
  4032 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  4033 circumvent possible incompatibilities when working on ML level.
  4034 
  4035 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  4036 
  4037 * New function listsum :: 'a list => 'a for arbitrary monoids.
  4038 Special syntax: "SUM x <- xs. f x" (and latex variants)
  4039 
  4040 * New syntax for Haskell-like list comprehension (input only), eg.
  4041 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  4042 
  4043 * The special syntax for function "filter" has changed from [x :
  4044 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  4045 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  4046 
  4047 * [a..b] is now defined for arbitrary linear orders.  It used to be
  4048 defined on nat only, as an abbreviation for [a..<Suc b]
  4049 INCOMPATIBILITY.
  4050 
  4051 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  4052 
  4053 * New functions "sorted" and "sort" in src/HOL/List.thy.
  4054 
  4055 * New lemma collection field_simps (an extension of ring_simps) for
  4056 manipulating (in)equations involving division. Multiplies with all
  4057 denominators that can be proved to be non-zero (in equations) or
  4058 positive/negative (in inequations).
  4059 
  4060 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  4061 have been improved and renamed to ring_simps, group_simps and
  4062 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  4063 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  4064 
  4065 * Theory Library/Commutative_Ring: switched from recdef to function
  4066 package; constants add, mul, pow now curried.  Infix syntax for
  4067 algebraic operations.
  4068 
  4069 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  4070 INCOMPATIBILITY.
  4071 
  4072 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  4073 INCOMPATIBILITY.
  4074 
  4075 * HOL/records: generalised field-update to take a function on the
  4076 field rather than the new value: r(|A := x|) is translated to A_update
  4077 (K x) r The K-combinator that is internally used is called K_record.
  4078 INCOMPATIBILITY: Usage of the plain update functions has to be
  4079 adapted.
  4080  
  4081 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  4082 * x = 0, which are required for a semiring.  Richer structures do not
  4083 inherit from semiring_0 anymore, because this property is a theorem
  4084 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  4085 there is more to prove, but this is mostly trivial.
  4086 
  4087 * Class "recpower" is generalized to arbitrary monoids, not just
  4088 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  4089 commutativity or semiring properties additionally.
  4090 
  4091 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  4092 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  4093 better use 'abbreviation'.
  4094 
  4095 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  4096 
  4097 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  4098 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  4099 significant changes for setting up numeral syntax for types:
  4100   - New constants Numeral.pred and Numeral.succ instead
  4101       of former Numeral.bin_pred and Numeral.bin_succ.
  4102   - Use integer operations instead of bin_add, bin_mult and so on.
  4103   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  4104   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  4105 
  4106 See src/HOL/Integ/IntArith.thy for an example setup.
  4107 
  4108 * Command 'normal_form' computes the normal form of a term that may
  4109 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  4110 produces ``[b, c, a]'' (without proof).  This command is suitable for
  4111 heavy-duty computations because the functions are compiled to ML
  4112 first.  Correspondingly, a method "normalization" is provided.  See
  4113 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  4114 
  4115 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  4116 25 like -->); output depends on the "iff" print_mode, the default is
  4117 "A = B" (with priority 50).
  4118 
  4119 * Relations less (<) and less_eq (<=) are also available on type bool.
  4120 Modified syntax to disallow nesting without explicit parentheses,
  4121 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  4122 INCOMPATIBILITY.
  4123 
  4124 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  4125 
  4126 * Relation composition operator "op O" now has precedence 75 and binds
  4127 stronger than union and intersection. INCOMPATIBILITY.
  4128 
  4129 * The old set interval syntax "{m..n(}" (and relatives) has been
  4130 removed.  Use "{m..<n}" (and relatives) instead.
  4131 
  4132 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  4133 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  4134 ``declare [[simproc del: neq]]''.
  4135 
  4136 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  4137 True/False.
  4138 
  4139 * Theorem Cons_eq_map_conv no longer declared as "simp".
  4140 
  4141 * Theorem setsum_mult renamed to setsum_right_distrib.
  4142 
  4143 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  4144 ``rule'' method.
  4145 
  4146 * Reimplemented methods "sat" and "satx", with several improvements:
  4147 goals no longer need to be stated as "<prems> ==> False", equivalences
  4148 (i.e. "=" on type bool) are handled, variable names of the form
  4149 "lit_<n>" are no longer reserved, significant speedup.
  4150 
  4151 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  4152 zChaff is still supported as well.
  4153 
  4154 * 'inductive' and 'datatype': provide projections of mutual rules,
  4155 bundled as foo_bar.inducts;
  4156 
  4157 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  4158 Library.
  4159 
  4160 * Library: moved theory Accessible_Part to main HOL.
  4161 
  4162 * Library: added theory Coinductive_List of potentially infinite lists
  4163 as greatest fixed-point.
  4164 
  4165 * Library: added theory AssocList which implements (finite) maps as
  4166 association lists.
  4167 
  4168 * Method "evaluation" solves goals (i.e. a boolean expression)
  4169 efficiently by compiling it to ML.  The goal is "proved" (via an
  4170 oracle) if it evaluates to True.
  4171 
  4172 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  4173 also when invoked by the simplifier.  This results in the Simplifier
  4174 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  4175 Configuration option fast_arith_split_limit=0 recovers the old
  4176 behavior.
  4177 
  4178 * Support for hex (0x20) and binary (0b1001) numerals.
  4179 
  4180 * New method: reify eqs (t), where eqs are equations for an
  4181 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  4182 parameter, computes a term s::'b and a list xs::'a list and proves the
  4183 theorem I xs s = t. This is also known as reification or quoting. The
  4184 resulting theorem is applied to the subgoal to substitute t with I xs
  4185 s.  If t is omitted, the subgoal itself is reified.
  4186 
  4187 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  4188 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  4189 where f is supposed to be a computable function (in the sense of code
  4190 generattion). The method uses reify to compute s and xs as above then
  4191 applies corr_thm and uses normalization by evaluation to "prove" f s =
  4192 r and finally gets the theorem t = r, which is again applied to the
  4193 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  4194 
  4195 * Reflection: Automatic reification now handels binding, an example is
  4196 available in src/HOL/ex/ReflectionEx.thy
  4197 
  4198 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  4199 command 'statespace' that is similar to 'record', but introduces an
  4200 abstract specification based on the locale infrastructure instead of
  4201 HOL types.  This leads to extra flexibility in composing state spaces,
  4202 in particular multiple inheritance and renaming of components.
  4203 
  4204 
  4205 *** HOL-Complex ***
  4206 
  4207 * Hyperreal: Functions root and sqrt are now defined on negative real
  4208 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  4209 Nonnegativity side conditions have been removed from many lemmas, so
  4210 that more subgoals may now be solved by simplification; potential
  4211 INCOMPATIBILITY.
  4212 
  4213 * Real: new type classes formalize real normed vector spaces and
  4214 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  4215 and norm :: 'a => real.
  4216 
  4217 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  4218 reals into other types. The overloaded constant Reals :: 'a set is now
  4219 defined as range of_real; potential INCOMPATIBILITY.
  4220 
  4221 * Real: proper support for ML code generation, including 'quickcheck'.
  4222 Reals are implemented as arbitrary precision rationals.
  4223 
  4224 * Hyperreal: Several constants that previously worked only for the
  4225 reals have been generalized, so they now work over arbitrary vector
  4226 spaces. Type annotations may need to be added in some cases; potential
  4227 INCOMPATIBILITY.
  4228 
  4229   Infinitesimal  :: ('a::real_normed_vector) star set
  4230   HFinite        :: ('a::real_normed_vector) star set
  4231   HInfinite      :: ('a::real_normed_vector) star set
  4232   approx         :: ('a::real_normed_vector) star => 'a star => bool
  4233   monad          :: ('a::real_normed_vector) star => 'a star set
  4234   galaxy         :: ('a::real_normed_vector) star => 'a star set
  4235   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  4236   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  4237   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  4238   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  4239   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  4240   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  4241   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  4242   sgn            :: 'a::real_normed_vector => 'a
  4243   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  4244 
  4245 * Complex: Some complex-specific constants are now abbreviations for
  4246 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  4247 hnorm.  Other constants have been entirely removed in favor of the
  4248 polymorphic versions (INCOMPATIBILITY):
  4249 
  4250   approx        <-- capprox
  4251   HFinite       <-- CFinite
  4252   HInfinite     <-- CInfinite
  4253   Infinitesimal <-- CInfinitesimal
  4254   monad         <-- cmonad
  4255   galaxy        <-- cgalaxy
  4256   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  4257   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  4258   (ns)deriv     <-- (ns)cderiv
  4259 
  4260 
  4261 *** HOL-Algebra ***
  4262 
  4263 * Formalisation of ideals and the quotient construction over rings.
  4264 
  4265 * Order and lattice theory no longer based on records.
  4266 INCOMPATIBILITY.
  4267 
  4268 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  4269 greatest_closed.  INCOMPATIBILITY.
  4270 
  4271 * Method algebra is now set up via an attribute.  For examples see
  4272 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  4273 of algebraic structures.
  4274 
  4275 * Renamed theory CRing to Ring.
  4276 
  4277 
  4278 *** HOL-Nominal ***
  4279 
  4280 * Substantial, yet incomplete support for nominal datatypes (binding
  4281 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  4282 src/HOL/Nominal/Examples.  Prospective users should consult
  4283 http://isabelle.in.tum.de/nominal/
  4284 
  4285 
  4286 *** ML ***
  4287 
  4288 * ML basics: just one true type int, which coincides with IntInf.int
  4289 (even on SML/NJ).
  4290 
  4291 * ML within Isar: antiquotations allow to embed statically-checked
  4292 formal entities in the source, referring to the context available at
  4293 compile-time.  For example:
  4294 
  4295 ML {* @{sort "{zero,one}"} *}
  4296 ML {* @{typ "'a => 'b"} *}
  4297 ML {* @{term "%x. x"} *}
  4298 ML {* @{prop "x == y"} *}
  4299 ML {* @{ctyp "'a => 'b"} *}
  4300 ML {* @{cterm "%x. x"} *}
  4301 ML {* @{cprop "x == y"} *}
  4302 ML {* @{thm asm_rl} *}
  4303 ML {* @{thms asm_rl} *}
  4304 ML {* @{type_name c} *}
  4305 ML {* @{type_syntax c} *}
  4306 ML {* @{const_name c} *}
  4307 ML {* @{const_syntax c} *}
  4308 ML {* @{context} *}
  4309 ML {* @{theory} *}
  4310 ML {* @{theory Pure} *}
  4311 ML {* @{theory_ref} *}
  4312 ML {* @{theory_ref Pure} *}
  4313 ML {* @{simpset} *}
  4314 ML {* @{claset} *}
  4315 ML {* @{clasimpset} *}
  4316 
  4317 The same works for sources being ``used'' within an Isar context.
  4318 
  4319 * ML in Isar: improved error reporting; extra verbosity with
  4320 ML_Context.trace enabled.
  4321 
  4322 * Pure/General/table.ML: the join operations now works via exceptions
  4323 DUP/SAME instead of type option. This is simpler in simple cases, and
  4324 admits slightly more efficient complex applications.
  4325 
  4326 * Pure: 'advanced' translation functions (parse_translation etc.) now
  4327 use Context.generic instead of just theory.
  4328 
  4329 * Pure: datatype Context.generic joins theory/Proof.context and
  4330 provides some facilities for code that works in either kind of
  4331 context, notably GenericDataFun for uniform theory and proof data.
  4332 
  4333 * Pure: simplified internal attribute type, which is now always
  4334 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  4335 local (Proof.context) attributes have been discontinued, while
  4336 minimizing code duplication. Thm.rule_attribute and
  4337 Thm.declaration_attribute build canonical attributes; see also structure
  4338 Context for further operations on Context.generic, notably
  4339 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  4340 declarations and definitions.
  4341 
  4342 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  4343 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  4344 init only required for impure data. INCOMPATIBILITY: empty really need
  4345 to be empty (no dependencies on theory content!)
  4346 
  4347 * Pure/kernel: consts certification ignores sort constraints given in
  4348 signature declarations. (This information is not relevant to the
  4349 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  4350 potential INCOMPATIBILITY.
  4351 
  4352 * Pure: axiomatic type classes are now purely definitional, with
  4353 explicit proofs of class axioms and super class relations performed
  4354 internally. See Pure/axclass.ML for the main internal interfaces --
  4355 notably AxClass.define_class supercedes AxClass.add_axclass, and
  4356 AxClass.axiomatize_class/classrel/arity supersede
  4357 Sign.add_classes/classrel/arities.
  4358 
  4359 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  4360 global/local versions on theory vs. Proof.context have been
  4361 discontinued; Attrib.syntax and Method.syntax have been adapted
  4362 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  4363 attributes, methods, etc.
  4364 
  4365 * Pure: several functions of signature "... -> theory -> theory * ..."
  4366 have been reoriented to "... -> theory -> ... * theory" in order to
  4367 allow natural usage in combination with the ||>, ||>>, |-> and
  4368 fold_map combinators.
  4369 
  4370 * Pure: official theorem names (closed derivations) and additional
  4371 comments (tags) are now strictly separate.  Name hints -- which are
  4372 maintained as tags -- may be attached any time without affecting the
  4373 derivation.
  4374 
  4375 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  4376 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  4377 achieve the old behaviour.
  4378 
  4379 * Pure: the "Goal" constant is now called "prop", supporting a
  4380 slightly more general idea of ``protecting'' meta-level rule
  4381 statements.
  4382 
  4383 * Pure: Logic.(un)varify only works in a global context, which is now
  4384 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  4385 Logic.legacy_(un)varify as temporary workaround.
  4386 
  4387 * Pure: structure Name provides scalable operations for generating
  4388 internal variable names, notably Name.variants etc.  This replaces
  4389 some popular functions from term.ML:
  4390 
  4391   Term.variant		->  Name.variant
  4392   Term.variantlist	->  Name.variant_list
  4393   Term.invent_names	->  Name.invent_list
  4394 
  4395 Note that low-level renaming rarely occurs in new code -- operations
  4396 from structure Variable are used instead (see below).
  4397 
  4398 * Pure: structure Variable provides fundamental operations for proper
  4399 treatment of fixed/schematic variables in a context.  For example,
  4400 Variable.import introduces fixes for schematics of given facts and
  4401 Variable.export reverses the effect (up to renaming) -- this replaces
  4402 various freeze_thaw operations.
  4403 
  4404 * Pure: structure Goal provides simple interfaces for
  4405 init/conclude/finish and tactical prove operations (replacing former
  4406 Tactic.prove).  Goal.prove is the canonical way to prove results
  4407 within a given context; Goal.prove_global is a degraded version for
  4408 theory level goals, including a global Drule.standard.  Note that
  4409 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  4410 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  4411 in a locale context).
  4412 
  4413 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  4414 and type checking (Syntax.check_term etc.), with common combinations
  4415 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  4416 which are considered legacy and await removal.
  4417 
  4418 * Pure/Syntax: generic interfaces for type unchecking
  4419 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  4420 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  4421 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  4422 available for convenience, but refer to the very same operations using
  4423 a mere theory instead of a full context.
  4424 
  4425 * Isar: simplified treatment of user-level errors, using exception
  4426 ERROR of string uniformly.  Function error now merely raises ERROR,
  4427 without any side effect on output channels.  The Isar toplevel takes
  4428 care of proper display of ERROR exceptions.  ML code may use plain
  4429 handle/can/try; cat_error may be used to concatenate errors like this:
  4430 
  4431   ... handle ERROR msg => cat_error msg "..."
  4432 
  4433 Toplevel ML code (run directly or through the Isar toplevel) may be
  4434 embedded into the Isar toplevel with exception display/debug like
  4435 this:
  4436 
  4437   Isar.toplevel (fn () => ...)
  4438 
  4439 INCOMPATIBILITY, removed special transform_error facilities, removed
  4440 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  4441 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  4442 -- use plain ERROR instead.
  4443 
  4444 * Isar: theory setup now has type (theory -> theory), instead of a
  4445 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  4446 
  4447 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  4448 ProofContext.debug/verbose flags.
  4449 
  4450 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  4451 theory before entering a proof state.  Transactions now always see a
  4452 quasi-functional intermediate checkpoint, both in interactive and
  4453 batch mode.
  4454 
  4455 * Isar: simplified interfaces for outer syntax.  Renamed
  4456 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  4457 OuterSyntax.add_parsers -- this functionality is now included in
  4458 OuterSyntax.command etc.  INCOMPATIBILITY.
  4459 
  4460 * Simplifier: the simpset of a running simplification process now
  4461 contains a proof context (cf. Simplifier.the_context), which is the
  4462 very context that the initial simpset has been retrieved from (by
  4463 simpset_of/local_simpset_of).  Consequently, all plug-in components
  4464 (solver, looper etc.) may depend on arbitrary proof data.
  4465 
  4466 * Simplifier.inherit_context inherits the proof context (plus the
  4467 local bounds) of the current simplification process; any simproc
  4468 etc. that calls the Simplifier recursively should do this!  Removed
  4469 former Simplifier.inherit_bounds, which is already included here --
  4470 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  4471 specify an explicit context using Simplifier.context/theory_context.
  4472 
  4473 * Simplifier/Classical Reasoner: more abstract interfaces
  4474 change_simpset/claset for modifying the simpset/claset reference of a
  4475 theory; raw versions simpset/claset_ref etc. have been discontinued --
  4476 INCOMPATIBILITY.
  4477 
  4478 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  4479 "Trueprop" etc.
  4480 
  4481 
  4482 *** System ***
  4483 
  4484 * settings: the default heap location within ISABELLE_HOME_USER now
  4485 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  4486 Isabelle installations.
  4487 
  4488 * isabelle-process: option -S (secure mode) disables some critical
  4489 operations, notably runtime compilation and evaluation of ML source
  4490 code.
  4491 
  4492 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  4493 
  4494 * Support for parallel execution, using native multicore support of
  4495 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  4496 independent theories, according to the given theory header
  4497 specifications. The maximum number of worker threads is specified via
  4498 usedir option -M or the "max-threads" setting in Proof General. A
  4499 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  4500 to 6 on a 8-core machine.  User-code needs to observe certain
  4501 guidelines for thread-safe programming, see appendix A in the Isar
  4502 Implementation manual.
  4503 
  4504 
  4505 
  4506 New in Isabelle2005 (October 2005)
  4507 ----------------------------------
  4508 
  4509 *** General ***
  4510 
  4511 * Theory headers: the new header syntax for Isar theories is
  4512 
  4513   theory <name>
  4514   imports <theory1> ... <theoryN>
  4515   uses <file1> ... <fileM>
  4516   begin
  4517 
  4518 where the 'uses' part is optional.  The previous syntax
  4519 
  4520   theory <name> = <theory1> + ... + <theoryN>:
  4521 
  4522 will disappear in the next release.  Use isatool fixheaders to convert
  4523 existing theory files.  Note that there is no change in ancient
  4524 non-Isar theories now, but these will disappear soon.
  4525 
  4526 * Theory loader: parent theories can now also be referred to via
  4527 relative and absolute paths.
  4528 
  4529 * Command 'find_theorems' searches for a list of criteria instead of a
  4530 list of constants. Known criteria are: intro, elim, dest, name:string,
  4531 simp:term, and any term. Criteria can be preceded by '-' to select
  4532 theorems that do not match. Intro, elim, dest select theorems that
  4533 match the current goal, name:s selects theorems whose fully qualified
  4534 name contain s, and simp:term selects all simplification rules whose
  4535 lhs match term.  Any other term is interpreted as pattern and selects
  4536 all theorems matching the pattern. Available in ProofGeneral under
  4537 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  4538 
  4539   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  4540 
  4541 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  4542 matching the current goal as introduction rule and not having "HOL."
  4543 in their name (i.e. not being defined in theory HOL).
  4544 
  4545 * Command 'thms_containing' has been discontinued in favour of
  4546 'find_theorems'; INCOMPATIBILITY.
  4547 
  4548 * Communication with Proof General is now 8bit clean, which means that
  4549 Unicode text in UTF-8 encoding may be used within theory texts (both
  4550 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4551 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4552 
  4553   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4554   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4555 
  4556 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4557 Classical Reasoner.  Typical big applications run around 2 times
  4558 faster.
  4559 
  4560 
  4561 *** Document preparation ***
  4562 
  4563 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4564 of raw sources.  Only those symbols that do not require additional
  4565 LaTeX packages (depending on comments in isabellesym.sty) are
  4566 displayed properly, everything else is left verbatim.  isatool display
  4567 and isatool print are used as front ends (these are subject to the
  4568 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4569 
  4570 * Command tags control specific markup of certain regions of text,
  4571 notably folding and hiding.  Predefined tags include "theory" (for
  4572 theory begin and end), "proof" for proof commands, and "ML" for
  4573 commands involving ML code; the additional tags "visible" and
  4574 "invisible" are unused by default.  Users may give explicit tag
  4575 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4576 interpretation of tags is determined by the LaTeX job during document
  4577 preparation: see option -V of isatool usedir, or options -n and -t of
  4578 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4579 \isadroptag.
  4580 
  4581 Several document versions may be produced at the same time via isatool
  4582 usedir (the generated index.html will link all of them).  Typical
  4583 specifications include ''-V document=theory,proof,ML'' to present
  4584 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4585 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4586 these parts without any formal replacement text.  The Isabelle site
  4587 default settings produce ''document'' and ''outline'' versions as
  4588 specified above.
  4589 
  4590 * Several new antiquotations:
  4591 
  4592   @{term_type term} prints a term with its type annotated;
  4593 
  4594   @{typeof term} prints the type of a term;
  4595 
  4596   @{const const} is the same as @{term const}, but checks that the
  4597   argument is a known logical constant;
  4598 
  4599   @{term_style style term} and @{thm_style style thm} print a term or
  4600   theorem applying a "style" to it
  4601 
  4602   @{ML text}
  4603 
  4604 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4605 definitions, equations, inequations etc., 'concl' printing only the
  4606 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4607 to print the specified premise.  TermStyle.add_style provides an ML
  4608 interface for introducing further styles.  See also the "LaTeX Sugar"
  4609 document practical applications.  The ML antiquotation prints
  4610 type-checked ML expressions verbatim.
  4611 
  4612 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4613 and 'text' support optional locale specification '(in loc)', which
  4614 specifies the default context for interpreting antiquotations.  For
  4615 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4616 
  4617 * Option 'locale=NAME' of antiquotations specifies an alternative
  4618 context interpreting the subsequent argument.  For example: @{thm
  4619 [locale=lattice] inf_assoc}.
  4620 
  4621 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4622 a proof context.
  4623 
  4624 * Proper output of antiquotations for theory commands involving a
  4625 proof context (such as 'locale' or 'theorem (in loc) ...').
  4626 
  4627 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4628 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4629 
  4630 * isatool usedir: new option -C (default true) controls whether option
  4631 -D should include a copy of the original document directory; -C false
  4632 prevents unwanted effects such as copying of administrative CVS data.
  4633 
  4634 
  4635 *** Pure ***
  4636 
  4637 * Considerably improved version of 'constdefs' command.  Now performs
  4638 automatic type-inference of declared constants; additional support for
  4639 local structure declarations (cf. locales and HOL records), see also
  4640 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4641 sequential dependencies of definitions within a single 'constdefs'
  4642 section; moreover, the declared name needs to be an identifier.  If
  4643 all fails, consider to fall back on 'consts' and 'defs' separately.
  4644 
  4645 * Improved indexed syntax and implicit structures.  First of all,
  4646 indexed syntax provides a notational device for subscripted
  4647 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4648 expressions.  Secondly, in a local context with structure
  4649 declarations, number indexes \<^sub>n or the empty index (default
  4650 number 1) refer to a certain fixed variable implicitly; option
  4651 show_structs controls printing of implicit structures.  Typical
  4652 applications of these concepts involve record types and locales.
  4653 
  4654 * New command 'no_syntax' removes grammar declarations (and
  4655 translations) resulting from the given syntax specification, which is
  4656 interpreted in the same manner as for the 'syntax' command.
  4657 
  4658 * 'Advanced' translation functions (parse_translation etc.) may depend
  4659 on the signature of the theory context being presently used for
  4660 parsing/printing, see also isar-ref manual.
  4661 
  4662 * Improved 'oracle' command provides a type-safe interface to turn an
  4663 ML expression of type theory -> T -> term into a primitive rule of
  4664 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4665 is already included here); see also FOL/ex/IffExample.thy;
  4666 INCOMPATIBILITY.
  4667 
  4668 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4669 before); "cI" is no longer bound, use "c.intro" instead.
  4670 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4671 axclasses vs. locales.
  4672 
  4673 * Improved internal renaming of symbolic identifiers -- attach primes
  4674 instead of base 26 numbers.
  4675 
  4676 * New flag show_question_marks controls printing of leading question
  4677 marks in schematic variable names.
  4678 
  4679 * In schematic variable names, *any* symbol following \<^isub> or
  4680 \<^isup> is now treated as part of the base name.  For example, the
  4681 following works without printing of awkward ".0" indexes:
  4682 
  4683   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4684     by simp
  4685 
  4686 * Inner syntax includes (*(*nested*) comments*).
  4687 
  4688 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4689 annotations as "(00...)".
  4690 
  4691 * Clear separation of logical types and nonterminals, where the latter
  4692 may only occur in 'syntax' specifications or type abbreviations.
  4693 Before that distinction was only partially implemented via type class
  4694 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4695 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4696 exotic syntax specifications may require further adaption
  4697 (e.g. Cube/Cube.thy).
  4698 
  4699 * Removed obsolete type class "logic", use the top sort {} instead.
  4700 Note that non-logical types should be declared as 'nonterminals'
  4701 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4702 specifications.
  4703 
  4704 * Attributes 'induct' and 'cases': type or set names may now be
  4705 locally fixed variables as well.
  4706 
  4707 * Simplifier: can now control the depth to which conditional rewriting
  4708 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4709 Limit.
  4710 
  4711 * Simplifier: simplification procedures may now take the current
  4712 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4713 interface), which is very useful for calling the Simplifier
  4714 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4715 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4716 low-level mk_simproc no longer applies Logic.varify internally, to
  4717 allow for use in a context of fixed variables.
  4718 
  4719 * thin_tac now works even if the assumption being deleted contains !!
  4720 or ==>.  More generally, erule now works even if the major premise of
  4721 the elimination rule contains !! or ==>.
  4722 
  4723 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4724 
  4725 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4726 from Pure, which contains all common declarations already.  Both
  4727 theories are defined via plain Isabelle/Isar .thy files.
  4728 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4729 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4730 use isatool fixcpure to adapt your theory and ML sources.
  4731 
  4732 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4733 selections of theorems in named facts via index ranges.
  4734 
  4735 * 'print_theorems': in theory mode, really print the difference
  4736 wrt. the last state (works for interactive theory development only),
  4737 in proof mode print all local facts (cf. 'print_facts');
  4738 
  4739 * 'hide': option '(open)' hides only base names.
  4740 
  4741 * More efficient treatment of intermediate checkpoints in interactive
  4742 theory development.
  4743 
  4744 * Code generator is now invoked via code_module (incremental code
  4745 generation) and code_library (modular code generation, ML structures
  4746 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4747 must be quoted when used as identifiers.
  4748 
  4749 * New 'value' command for reading, evaluating and printing terms using
  4750 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4751 quoted when used as identifier.
  4752 
  4753 
  4754 *** Locales ***
  4755 
  4756 * New commands for the interpretation of locale expressions in
  4757 theories (1), locales (2) and proof contexts (3).  These generate
  4758 proof obligations from the expression specification.  After the
  4759 obligations have been discharged, theorems of the expression are added
  4760 to the theory, target locale or proof context.  The synopsis of the
  4761 commands is a follows:
  4762 
  4763   (1) interpretation expr inst
  4764   (2) interpretation target < expr
  4765   (3) interpret expr inst
  4766 
  4767 Interpretation in theories and proof contexts require a parameter
  4768 instantiation of terms from the current context.  This is applied to
  4769 specifications and theorems of the interpreted expression.
  4770 Interpretation in locales only permits parameter renaming through the
  4771 locale expression.  Interpretation is smart in that interpretations
  4772 that are active already do not occur in proof obligations, neither are
  4773 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4774 inspect active interpretations of a particular locale.  For details,
  4775 see the Isar Reference manual.  Examples can be found in
  4776 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4777 
  4778 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4779 'interpret' instead.
  4780 
  4781 * New context element 'constrains' for adding type constraints to
  4782 parameters.
  4783 
  4784 * Context expressions: renaming of parameters with syntax
  4785 redeclaration.
  4786 
  4787 * Locale declaration: 'includes' disallowed.
  4788 
  4789 * Proper static binding of attribute syntax -- i.e. types / terms /
  4790 facts mentioned as arguments are always those of the locale definition
  4791 context, independently of the context of later invocations.  Moreover,
  4792 locale operations (renaming and type / term instantiation) are applied
  4793 to attribute arguments as expected.
  4794 
  4795 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4796 actual attributes; rare situations may require Attrib.attribute to
  4797 embed those attributes into Attrib.src that lack concrete syntax.
  4798 Attribute implementations need to cooperate properly with the static
  4799 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4800 Attrib.XXX_thm etc. already do the right thing without further
  4801 intervention.  Only unusual applications -- such as "where" or "of"
  4802 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4803 on the context and the facts involved -- may have to assign parsed
  4804 values to argument tokens explicitly.
  4805 
  4806 * Changed parameter management in theorem generation for long goal
  4807 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4808 theorem statement in rare situations.
  4809 
  4810 * Locale inspection command 'print_locale' omits notes elements.  Use
  4811 'print_locale!' to have them included in the output.
  4812 
  4813 
  4814 *** Provers ***
  4815 
  4816 * Provers/hypsubst.ML: improved version of the subst method, for
  4817 single-step rewriting: it now works in bound variable contexts. New is
  4818 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  4819 rewrite a different subterm than the original subst method, which is
  4820 still available as 'simplesubst'.
  4821 
  4822 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  4823 and quasi orders.
  4824 
  4825 * Provers/trancl.ML: new transitivity reasoner for transitive and
  4826 reflexive-transitive closure of relations.
  4827 
  4828 * Provers/blast.ML: new reference depth_limit to make blast's depth
  4829 limit (previously hard-coded with a value of 20) user-definable.
  4830 
  4831 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  4832 is peformed already.  Object-logics merely need to finish their
  4833 initial simpset configuration as before.  INCOMPATIBILITY.
  4834 
  4835 
  4836 *** HOL ***
  4837 
  4838 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  4839 
  4840   syntax (epsilon)
  4841     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  4842 
  4843 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  4844 and x-symbol; use option '-m epsilon' to get it actually printed.
  4845 Moreover, the mathematically important symbolic identifier \<epsilon>
  4846 becomes available as variable, constant etc.  INCOMPATIBILITY,
  4847 
  4848 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  4849 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  4850 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  4851 support corresponding Isar calculations.
  4852 
  4853 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  4854 instead of ":".
  4855 
  4856 * theory SetInterval: changed the syntax for open intervals:
  4857 
  4858   Old       New
  4859   {..n(}    {..<n}
  4860   {)n..}    {n<..}
  4861   {m..n(}   {m..<n}
  4862   {)m..n}   {m<..n}
  4863   {)m..n(}  {m<..<n}
  4864 
  4865 The old syntax is still supported but will disappear in the next
  4866 release.  For conversion use the following Emacs search and replace
  4867 patterns (these are not perfect but work quite well):
  4868 
  4869   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  4870   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  4871 
  4872 * Theory Commutative_Ring (in Library): method comm_ring for proving
  4873 equalities in commutative rings; method 'algebra' provides a generic
  4874 interface.
  4875 
  4876 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  4877 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  4878 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  4879 be a tuple pattern.
  4880 
  4881 Some new syntax forms are available:
  4882 
  4883   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  4884   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  4885   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  4886   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  4887 
  4888 The latter form "\<Sum>x < k. e" used to be based on a separate
  4889 function "Summation", which has been discontinued.
  4890 
  4891 * theory Finite_Set: in structured induction proofs, the insert case
  4892 is now 'case (insert x F)' instead of the old counterintuitive 'case
  4893 (insert F x)'.
  4894 
  4895 * The 'refute' command has been extended to support a much larger
  4896 fragment of HOL, including axiomatic type classes, constdefs and
  4897 typedefs, inductive datatypes and recursion.
  4898 
  4899 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  4900 Requires zChaff with proof generation to be installed.  See
  4901 HOL/ex/SAT_Examples.thy for examples.
  4902 
  4903 * Datatype induction via method 'induct' now preserves the name of the
  4904 induction variable. For example, when proving P(xs::'a list) by
  4905 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  4906 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  4907 in unstructured proof scripts.
  4908 
  4909 * Reworked implementation of records.  Improved scalability for
  4910 records with many fields, avoiding performance problems for type
  4911 inference. Records are no longer composed of nested field types, but
  4912 of nested extension types. Therefore the record type only grows linear
  4913 in the number of extensions and not in the number of fields.  The
  4914 top-level (users) view on records is preserved.  Potential
  4915 INCOMPATIBILITY only in strange cases, where the theory depends on the
  4916 old record representation. The type generated for a record is called
  4917 <record_name>_ext_type.
  4918 
  4919 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  4920 proofs triggered by a record definition or a simproc (if
  4921 quick_and_dirty is enabled).  Definitions of large records can take
  4922 quite long.
  4923 
  4924 New simproc record_upd_simproc for simplification of multiple record
  4925 updates enabled by default.  Moreover, trivial updates are also
  4926 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  4927 occasionally, since simplification is more powerful by default.
  4928 
  4929 * typedef: proper support for polymorphic sets, which contain extra
  4930 type-variables in the term.
  4931 
  4932 * Simplifier: automatically reasons about transitivity chains
  4933 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  4934 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  4935 old proofs break occasionally as simplification may now solve more
  4936 goals than previously.
  4937 
  4938 * Simplifier: converts x <= y into x = y if assumption y <= x is
  4939 present.  Works for all partial orders (class "order"), in particular
  4940 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  4941 just like y <= x.
  4942 
  4943 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  4944 bound variable or a constant then the let is unfolded.  Otherwise
  4945 first a is simplified to b, and then f b is simplified to g. If
  4946 possible we abstract b from g arriving at "let x = b in h x",
  4947 otherwise we unfold the let and arrive at g.  The simproc can be
  4948 enabled/disabled by the reference use_let_simproc.  Potential
  4949 INCOMPATIBILITY since simplification is more powerful by default.
  4950 
  4951 * Classical reasoning: the meson method now accepts theorems as arguments.
  4952 
  4953 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  4954 jobs to provide advice on the provability of subgoals.
  4955 
  4956 * Theory OrderedGroup and Ring_and_Field: various additions and
  4957 improvements to faciliate calculations involving equalities and
  4958 inequalities.
  4959 
  4960 The following theorems have been eliminated or modified
  4961 (INCOMPATIBILITY):
  4962 
  4963   abs_eq             now named abs_of_nonneg
  4964   abs_of_ge_0        now named abs_of_nonneg
  4965   abs_minus_eq       now named abs_of_nonpos
  4966   imp_abs_id         now named abs_of_nonneg
  4967   imp_abs_neg_id     now named abs_of_nonpos
  4968   mult_pos           now named mult_pos_pos
  4969   mult_pos_le        now named mult_nonneg_nonneg
  4970   mult_pos_neg_le    now named mult_nonneg_nonpos
  4971   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  4972   mult_neg           now named mult_neg_neg
  4973   mult_neg_le        now named mult_nonpos_nonpos
  4974 
  4975 * The following lemmas in Ring_and_Field have been added to the simplifier:
  4976      
  4977      zero_le_square
  4978      not_square_less_zero 
  4979 
  4980   The following lemmas have been deleted from Real/RealPow:
  4981   
  4982      realpow_zero_zero
  4983      realpow_two
  4984      realpow_less
  4985      zero_le_power
  4986      realpow_two_le
  4987      abs_realpow_two
  4988      realpow_two_abs     
  4989 
  4990 * Theory Parity: added rules for simplifying exponents.
  4991 
  4992 * Theory List:
  4993 
  4994 The following theorems have been eliminated or modified
  4995 (INCOMPATIBILITY):
  4996 
  4997   list_all_Nil       now named list_all.simps(1)
  4998   list_all_Cons      now named list_all.simps(2)
  4999   list_all_conv      now named list_all_iff
  5000   set_mem_eq         now named mem_iff
  5001 
  5002 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  5003 asymptotic "big O" calculations.  See the notes in BigO.thy.
  5004 
  5005 
  5006 *** HOL-Complex ***
  5007 
  5008 * Theory RealDef: better support for embedding natural numbers and
  5009 integers in the reals.
  5010 
  5011 The following theorems have been eliminated or modified
  5012 (INCOMPATIBILITY):
  5013 
  5014   exp_ge_add_one_self  now requires no hypotheses
  5015   real_of_int_add      reversed direction of equality (use [symmetric])
  5016   real_of_int_minus    reversed direction of equality (use [symmetric])
  5017   real_of_int_diff     reversed direction of equality (use [symmetric])
  5018   real_of_int_mult     reversed direction of equality (use [symmetric])
  5019 
  5020 * Theory RComplete: expanded support for floor and ceiling functions.
  5021 
  5022 * Theory Ln is new, with properties of the natural logarithm
  5023 
  5024 * Hyperreal: There is a new type constructor "star" for making
  5025 nonstandard types.  The old type names are now type synonyms:
  5026 
  5027   hypreal = real star
  5028   hypnat = nat star
  5029   hcomplex = complex star
  5030 
  5031 * Hyperreal: Many groups of similarly-defined constants have been
  5032 replaced by polymorphic versions (INCOMPATIBILITY):
  5033 
  5034   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  5035 
  5036   starset      <-- starsetNat, starsetC
  5037   *s*          <-- *sNat*, *sc*
  5038   starset_n    <-- starsetNat_n, starsetC_n
  5039   *sn*         <-- *sNatn*, *scn*
  5040   InternalSets <-- InternalNatSets, InternalCSets
  5041 
  5042   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  5043   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  5044   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  5045   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  5046   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  5047 
  5048 * Hyperreal: Many type-specific theorems have been removed in favor of
  5049 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  5050 
  5051   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  5052   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  5053   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  5054   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  5055   right_minus <-- hypreal_add_minus
  5056   left_minus <-- {hypreal,hcomplex}_add_minus_left
  5057   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  5058   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  5059   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  5060   mult_1_right <-- hcomplex_mult_one_right
  5061   mult_zero_left <-- hcomplex_mult_zero_left
  5062   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  5063   right_distrib <-- hypnat_add_mult_distrib2
  5064   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  5065   right_inverse <-- hypreal_mult_inverse
  5066   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  5067   order_refl <-- {hypreal,hypnat}_le_refl
  5068   order_trans <-- {hypreal,hypnat}_le_trans
  5069   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  5070   order_less_le <-- {hypreal,hypnat}_less_le
  5071   linorder_linear <-- {hypreal,hypnat}_le_linear
  5072   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  5073   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  5074   add_nonneg_nonneg <-- hypreal_le_add_order
  5075 
  5076 * Hyperreal: Separate theorems having to do with type-specific
  5077 versions of constants have been merged into theorems that apply to the
  5078 new polymorphic constants (INCOMPATIBILITY):
  5079 
  5080   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  5081   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  5082   STAR_Un <-- {STAR,NatStar,STARC}_Un
  5083   STAR_Int <-- {STAR,NatStar,STARC}_Int
  5084   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  5085   STAR_subset <-- {STAR,NatStar,STARC}_subset
  5086   STAR_mem <-- {STAR,NatStar,STARC}_mem
  5087   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  5088   STAR_diff <-- {STAR,STARC}_diff
  5089   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  5090     STARC_hcomplex_of_complex}_image_subset
  5091   starset_n_Un <-- starset{Nat,C}_n_Un
  5092   starset_n_Int <-- starset{Nat,C}_n_Int
  5093   starset_n_Compl <-- starset{Nat,C}_n_Compl
  5094   starset_n_diff <-- starset{Nat,C}_n_diff
  5095   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  5096   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  5097   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  5098   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  5099   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  5100   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  5101   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  5102   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  5103   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  5104   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  5105   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  5106   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  5107   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  5108   starfun_diff <-- starfun{C,RC,CR}_diff
  5109   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  5110   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  5111   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  5112   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  5113   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  5114   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  5115   starfun_Id <-- starfunC_Id
  5116   starfun_approx <-- starfun{Nat,CR}_approx
  5117   starfun_capprox <-- starfun{C,RC}_capprox
  5118   starfun_abs <-- starfunNat_rabs
  5119   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  5120   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  5121   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  5122   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  5123   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  5124   starfun_add_approx <-- starfunCR_add_approx
  5125   starfun_inverse_inverse <-- starfunC_inverse_inverse
  5126   starfun_divide <-- starfun{C,CR,RC}_divide
  5127   starfun_n <-- starfun{Nat,C}_n
  5128   starfun_n_mult <-- starfun{Nat,C}_n_mult
  5129   starfun_n_add <-- starfun{Nat,C}_n_add
  5130   starfun_n_add_minus <-- starfunNat_n_add_minus
  5131   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  5132   starfun_n_minus <-- starfun{Nat,C}_n_minus
  5133   starfun_n_eq <-- starfun{Nat,C}_n_eq
  5134 
  5135   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  5136   star_n_minus <-- {hypreal,hcomplex}_minus
  5137   star_n_diff <-- {hypreal,hcomplex}_diff
  5138   star_n_mult <-- {hypreal,hcomplex}_mult
  5139   star_n_inverse <-- {hypreal,hcomplex}_inverse
  5140   star_n_le <-- {hypreal,hypnat}_le
  5141   star_n_less <-- {hypreal,hypnat}_less
  5142   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  5143   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  5144   star_n_abs <-- hypreal_hrabs
  5145   star_n_divide <-- hcomplex_divide
  5146 
  5147   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  5148   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  5149   star_of_diff <-- hypreal_of_real_diff
  5150   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  5151   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  5152   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  5153   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  5154   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  5155   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  5156   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  5157   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  5158   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  5159   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  5160   star_of_number_of <-- {hypreal,hcomplex}_number_of
  5161   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  5162   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  5163   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  5164   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  5165   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  5166   star_of_power <-- hypreal_of_real_power
  5167   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  5168 
  5169 * Hyperreal: new method "transfer" that implements the transfer
  5170 principle of nonstandard analysis. With a subgoal that mentions
  5171 nonstandard types like "'a star", the command "apply transfer"
  5172 replaces it with an equivalent one that mentions only standard types.
  5173 To be successful, all free variables must have standard types; non-
  5174 standard variables must have explicit universal quantifiers.
  5175 
  5176 * Hyperreal: A theory of Taylor series.
  5177 
  5178 
  5179 *** HOLCF ***
  5180 
  5181 * Discontinued special version of 'constdefs' (which used to support
  5182 continuous functions) in favor of the general Pure one with full
  5183 type-inference.
  5184 
  5185 * New simplification procedure for solving continuity conditions; it
  5186 is much faster on terms with many nested lambda abstractions (cubic
  5187 instead of exponential time).
  5188 
  5189 * New syntax for domain package: selector names are now optional.
  5190 Parentheses should be omitted unless argument is lazy, for example:
  5191 
  5192   domain 'a stream = cons "'a" (lazy "'a stream")
  5193 
  5194 * New command 'fixrec' for defining recursive functions with pattern
  5195 matching; defining multiple functions with mutual recursion is also
  5196 supported.  Patterns may include the constants cpair, spair, up, sinl,
  5197 sinr, or any data constructor defined by the domain package. The given
  5198 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  5199 syntax and examples.
  5200 
  5201 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  5202 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  5203 but the proof obligation additionally includes an admissibility
  5204 requirement. The packages generate instances of class cpo or pcpo,
  5205 with continuity and strictness theorems for Rep and Abs.
  5206 
  5207 * HOLCF: Many theorems have been renamed according to a more standard naming
  5208 scheme (INCOMPATIBILITY):
  5209 
  5210   foo_inject:  "foo$x = foo$y ==> x = y"
  5211   foo_eq:      "(foo$x = foo$y) = (x = y)"
  5212   foo_less:    "(foo$x << foo$y) = (x << y)"
  5213   foo_strict:  "foo$UU = UU"
  5214   foo_defined: "... ==> foo$x ~= UU"
  5215   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  5216 
  5217 
  5218 *** ZF ***
  5219 
  5220 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  5221 including the First Isomorphism Theorem (on quotienting by the kernel
  5222 of a homomorphism).
  5223 
  5224 * ZF/Simplifier: install second copy of type solver that actually
  5225 makes use of TC rules declared to Isar proof contexts (or locales);
  5226 the old version is still required for ML proof scripts.
  5227 
  5228 
  5229 *** Cube ***
  5230 
  5231 * Converted to Isar theory format; use locales instead of axiomatic
  5232 theories.
  5233 
  5234 
  5235 *** ML ***
  5236 
  5237 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  5238 for ||>, ||>>, |>>,
  5239 
  5240 * Pure/library.ML no longer defines its own option datatype, but uses
  5241 that of the SML basis, which has constructors NONE and SOME instead of
  5242 None and Some, as well as exception Option.Option instead of OPTION.
  5243 The functions the, if_none, is_some, is_none have been adapted
  5244 accordingly, while Option.map replaces apsome.
  5245 
  5246 * Pure/library.ML: the exception LIST has been given up in favour of
  5247 the standard exceptions Empty and Subscript, as well as
  5248 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  5249 superceded by the standard hd and tl functions etc.
  5250 
  5251 A number of basic list functions are no longer exported to the ML
  5252 toplevel, as they are variants of predefined functions.  The following
  5253 suggests how one can translate existing code:
  5254 
  5255     rev_append xs ys = List.revAppend (xs, ys)
  5256     nth_elem (i, xs) = List.nth (xs, i)
  5257     last_elem xs = List.last xs
  5258     flat xss = List.concat xss
  5259     seq fs = List.app fs
  5260     partition P xs = List.partition P xs
  5261     mapfilter f xs = List.mapPartial f xs
  5262 
  5263 * Pure/library.ML: several combinators for linear functional
  5264 transformations, notably reverse application and composition:
  5265 
  5266   x |> f                f #> g
  5267   (x, y) |-> f          f #-> g
  5268 
  5269 * Pure/library.ML: introduced/changed precedence of infix operators:
  5270 
  5271   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  5272   infix 2 ?;
  5273   infix 3 o oo ooo oooo;
  5274   infix 4 ~~ upto downto;
  5275 
  5276 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  5277 infix operators.
  5278 
  5279 * Pure/library.ML: natural list combinators fold, fold_rev, and
  5280 fold_map support linear functional transformations and nesting.  For
  5281 example:
  5282 
  5283   fold f [x1, ..., xN] y =
  5284     y |> f x1 |> ... |> f xN
  5285 
  5286   (fold o fold) f [xs1, ..., xsN] y =
  5287     y |> fold f xs1 |> ... |> fold f xsN
  5288 
  5289   fold f [x1, ..., xN] =
  5290     f x1 #> ... #> f xN
  5291 
  5292   (fold o fold) f [xs1, ..., xsN] =
  5293     fold f xs1 #> ... #> fold f xsN
  5294 
  5295 * Pure/library.ML: the following selectors on type 'a option are
  5296 available:
  5297 
  5298   the:               'a option -> 'a  (*partial*)
  5299   these:             'a option -> 'a  where 'a = 'b list
  5300   the_default: 'a -> 'a option -> 'a
  5301   the_list:          'a option -> 'a list
  5302 
  5303 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5304 basic operations for association lists, following natural argument
  5305 order; moreover the explicit equality predicate passed here avoids
  5306 potentially expensive polymorphic runtime equality checks.
  5307 The old functions may be expressed as follows:
  5308 
  5309   assoc = uncurry (AList.lookup (op =))
  5310   assocs = these oo AList.lookup (op =)
  5311   overwrite = uncurry (AList.update (op =)) o swap
  5312 
  5313 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5314 
  5315   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  5316   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  5317 
  5318 replacing make_keylist and keyfilter (occassionally used)
  5319 Naive rewrites:
  5320 
  5321   make_keylist = AList.make
  5322   keyfilter = AList.find (op =)
  5323 
  5324 * eq_fst and eq_snd now take explicit equality parameter, thus
  5325   avoiding eqtypes. Naive rewrites:
  5326 
  5327     eq_fst = eq_fst (op =)
  5328     eq_snd = eq_snd (op =)
  5329 
  5330 * Removed deprecated apl and apr (rarely used).
  5331   Naive rewrites:
  5332 
  5333     apl (n, op) =>>= curry op n
  5334     apr (op, m) =>>= fn n => op (n, m)
  5335 
  5336 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  5337 provides a reasonably efficient light-weight implementation of sets as
  5338 lists.
  5339 
  5340 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  5341 few new operations; existing lookup and update are now curried to
  5342 follow natural argument order (for use with fold etc.);
  5343 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  5344 
  5345 * Pure/General: output via the Isabelle channels of
  5346 writeln/warning/error etc. is now passed through Output.output, with a
  5347 hook for arbitrary transformations depending on the print_mode
  5348 (cf. Output.add_mode -- the first active mode that provides a output
  5349 function wins).  Already formatted output may be embedded into further
  5350 text via Output.raw; the result of Pretty.string_of/str_of and derived
  5351 functions (string_of_term/cterm/thm etc.) is already marked raw to
  5352 accommodate easy composition of diagnostic messages etc.  Programmers
  5353 rarely need to care about Output.output or Output.raw at all, with
  5354 some notable exceptions: Output.output is required when bypassing the
  5355 standard channels (writeln etc.), or in token translations to produce
  5356 properly formatted results; Output.raw is required when capturing
  5357 already output material that will eventually be presented to the user
  5358 a second time.  For the default print mode, both Output.output and
  5359 Output.raw have no effect.
  5360 
  5361 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  5362 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  5363 cumulative results are displayed at the end of a batch session.
  5364 
  5365 * Pure/General: File.sysify_path and File.quote_sysify path have been
  5366 replaced by File.platform_path and File.shell_path (with appropriate
  5367 hooks).  This provides a clean interface for unusual systems where the
  5368 internal and external process view of file names are different.
  5369 
  5370 * Pure: more efficient orders for basic syntactic entities: added
  5371 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  5372 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  5373 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  5374 orders now -- potential INCOMPATIBILITY for code that depends on a
  5375 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  5376 Library.sort_strings on result).
  5377 
  5378 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  5379 fold_types traverse types/terms from left to right, observing natural
  5380 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  5381 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  5382 
  5383 * Pure: name spaces have been refined, with significant changes of the
  5384 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  5385 to extern(_table).  The plain name entry path is superceded by a
  5386 general 'naming' context, which also includes the 'policy' to produce
  5387 a fully qualified name and external accesses of a fully qualified
  5388 name; NameSpace.extend is superceded by context dependent
  5389 Sign.declare_name.  Several theory and proof context operations modify
  5390 the naming context.  Especially note Theory.restore_naming and
  5391 ProofContext.restore_naming to get back to a sane state; note that
  5392 Theory.add_path is no longer sufficient to recover from
  5393 Theory.absolute_path in particular.
  5394 
  5395 * Pure: new flags short_names (default false) and unique_names
  5396 (default true) for controlling output of qualified names.  If
  5397 short_names is set, names are printed unqualified.  If unique_names is
  5398 reset, the name prefix is reduced to the minimum required to achieve
  5399 the original result when interning again, even if there is an overlap
  5400 with earlier declarations.
  5401 
  5402 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  5403 now 'extend', and 'merge' gets an additional Pretty.pp argument
  5404 (useful for printing error messages).  INCOMPATIBILITY.
  5405 
  5406 * Pure: major reorganization of the theory context.  Type Sign.sg and
  5407 Theory.theory are now identified, referring to the universal
  5408 Context.theory (see Pure/context.ML).  Actual signature and theory
  5409 content is managed as theory data.  The old code and interfaces were
  5410 spread over many files and structures; the new arrangement introduces
  5411 considerable INCOMPATIBILITY to gain more clarity:
  5412 
  5413   Context -- theory management operations (name, identity, inclusion,
  5414     parents, ancestors, merge, etc.), plus generic theory data;
  5415 
  5416   Sign -- logical signature and syntax operations (declaring consts,
  5417     types, etc.), plus certify/read for common entities;
  5418 
  5419   Theory -- logical theory operations (stating axioms, definitions,
  5420     oracles), plus a copy of logical signature operations (consts,
  5421     types, etc.); also a few basic management operations (Theory.copy,
  5422     Theory.merge, etc.)
  5423 
  5424 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  5425 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  5426 for convenience -- they merely return the theory.
  5427 
  5428 * Pure: type Type.tsig is superceded by theory in most interfaces.
  5429 
  5430 * Pure: the Isar proof context type is already defined early in Pure
  5431 as Context.proof (note that ProofContext.context and Proof.context are
  5432 aliases, where the latter is the preferred name).  This enables other
  5433 Isabelle components to refer to that type even before Isar is present.
  5434 
  5435 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  5436 typeK, constK, axiomK, oracleK), but provide explicit operations for
  5437 any of these kinds.  For example, Sign.intern typeK is now
  5438 Sign.intern_type, Theory.hide_space Sign.typeK is now
  5439 Theory.hide_types.  Also note that former
  5440 Theory.hide_classes/types/consts are now
  5441 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  5442 internalize their arguments!  INCOMPATIBILITY.
  5443 
  5444 * Pure: get_thm interface (of PureThy and ProofContext) expects
  5445 datatype thmref (with constructors Name and NameSelection) instead of
  5446 plain string -- INCOMPATIBILITY;
  5447 
  5448 * Pure: cases produced by proof methods specify options, where NONE
  5449 means to remove case bindings -- INCOMPATIBILITY in
  5450 (RAW_)METHOD_CASES.
  5451 
  5452 * Pure: the following operations retrieve axioms or theorems from a
  5453 theory node or theory hierarchy, respectively:
  5454 
  5455   Theory.axioms_of: theory -> (string * term) list
  5456   Theory.all_axioms_of: theory -> (string * term) list
  5457   PureThy.thms_of: theory -> (string * thm) list
  5458   PureThy.all_thms_of: theory -> (string * thm) list
  5459 
  5460 * Pure: print_tac now outputs the goal through the trace channel.
  5461 
  5462 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  5463 Reference Toplevel.debug (default false) controls detailed printing
  5464 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  5465 controls execution profiling -- set to 1 for time and 2 for space
  5466 (both increase the runtime).
  5467 
  5468 * Isar session: The initial use of ROOT.ML is now always timed,
  5469 i.e. the log will show the actual process times, in contrast to the
  5470 elapsed wall-clock time that the outer shell wrapper produces.
  5471 
  5472 * Simplifier: improved handling of bound variables (nameless
  5473 representation, avoid allocating new strings).  Simprocs that invoke
  5474 the Simplifier recursively should use Simplifier.inherit_bounds to
  5475 avoid local name clashes.  Failure to do so produces warnings
  5476 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  5477 for further details.
  5478 
  5479 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  5480 bindings for all theorems stored within a given theory; this may help
  5481 in porting non-Isar theories to Isar ones, while keeping ML proof
  5482 scripts for the time being.
  5483 
  5484 * ML operator HTML.with_charset specifies the charset begin used for
  5485 generated HTML files.  For example:
  5486 
  5487   HTML.with_charset "utf-8" use_thy "Hebrew";
  5488   HTML.with_charset "utf-8" use_thy "Chinese";
  5489 
  5490 
  5491 *** System ***
  5492 
  5493 * Allow symlinks to all proper Isabelle executables (Isabelle,
  5494 isabelle, isatool etc.).
  5495 
  5496 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  5497 isatool doc, isatool mkdir, display_drafts etc.).
  5498 
  5499 * isatool usedir: option -f allows specification of the ML file to be
  5500 used by Isabelle; default is ROOT.ML.
  5501 
  5502 * New isatool version outputs the version identifier of the Isabelle
  5503 distribution being used.
  5504 
  5505 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  5506 (containing Boolean satisfiability problems) into Isabelle/HOL
  5507 theories.
  5508 
  5509 
  5510 
  5511 New in Isabelle2004 (April 2004)
  5512 --------------------------------
  5513 
  5514 *** General ***
  5515 
  5516 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  5517   Replaces linorder.ML.
  5518 
  5519 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  5520   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  5521   (\<a>...\<z>), are now considered normal letters, and can therefore
  5522   be used anywhere where an ASCII letter (a...zA...Z) has until
  5523   now. COMPATIBILITY: This obviously changes the parsing of some
  5524   terms, especially where a symbol has been used as a binder, say
  5525   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  5526   as an identifier.  Fix it by inserting a space around former
  5527   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  5528   existing theory and ML files.
  5529 
  5530 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  5531 
  5532 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  5533   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  5534   a normal (but invisible) letter. For multiple letter subscripts repeat
  5535   \<^isub> like this: x\<^isub>1\<^isub>2.
  5536 
  5537 * Pure: There are now sub-/superscripts that can span more than one
  5538   character. Text between \<^bsub> and \<^esub> is set in subscript in
  5539   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  5540   superscript. The new control characters are not identifier parts.
  5541 
  5542 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5543   content of "..." to the latex file instead of \isacntrl... . The "..."
  5544   may consist of any printable characters excluding the end bracket >.
  5545 
  5546 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5547   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5548   declare constants "final", which prevents their being given a definition
  5549   later.  It is useful for constants whose behaviour is fixed axiomatically
  5550   rather than definitionally, such as the meta-logic connectives.
  5551 
  5552 * Pure: 'instance' now handles general arities with general sorts
  5553   (i.e. intersections of classes),
  5554 
  5555 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5556   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5557   It can be changed to alter the colors/layout of generated pages.
  5558 
  5559 
  5560 *** Isar ***
  5561 
  5562 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5563   cut_tac, subgoal_tac and thin_tac:
  5564   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5565     locales are no longer forced to write Isar proof scripts.
  5566     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5567     emulations.
  5568   - INCOMPATIBILITY: names of variables to be instantiated may no
  5569     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5570     This is consistent with the instantiation attribute "where".
  5571 
  5572 * Attributes "where" and "of":
  5573   - Now take type variables of instantiated theorem into account when reading
  5574     the instantiation string.  This fixes a bug that caused instantiated
  5575     theorems to have too special types in some circumstances.
  5576   - "where" permits explicit instantiations of type variables.
  5577 
  5578 * Calculation commands "moreover" and "also" no longer interfere with
  5579   current facts ("this"), admitting arbitrary combinations with "then"
  5580   and derived forms.
  5581 
  5582 * Locales:
  5583   - Goal statements involving the context element "includes" no longer
  5584     generate theorems with internal delta predicates (those ending on
  5585     "_axioms") in the premise.
  5586     Resolve particular premise with <locale>.intro to obtain old form.
  5587   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5588     specification and "includes" elements in goal statement.
  5589   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5590     [intro?] and [elim?] (respectively) by default.
  5591   - Experimental command for instantiation of locales in proof contexts:
  5592         instantiate <label>[<attrs>]: <loc>
  5593     Instantiates locale <loc> and adds all its theorems to the current context
  5594     taking into account their attributes.  Label and attrs are optional
  5595     modifiers, like in theorem declarations.  If present, names of
  5596     instantiated theorems are qualified with <label>, and the attributes
  5597     <attrs> are applied after any attributes these theorems might have already.
  5598       If the locale has assumptions, a chained fact of the form
  5599     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5600     are derived.  The command does not support old-style locales declared
  5601     with "locale (open)".
  5602       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5603 
  5604 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5605   (Isar) contexts.
  5606 
  5607 
  5608 *** HOL ***
  5609 
  5610 * Proof import: new image HOL4 contains the imported library from
  5611   the HOL4 system with about 2500 theorems. It is imported by
  5612   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5613   can be used like any other Isabelle image.  See
  5614   HOL/Import/HOL/README for more information.
  5615 
  5616 * Simplifier:
  5617   - Much improved handling of linear and partial orders.
  5618     Reasoners for linear and partial orders are set up for type classes
  5619     "linorder" and "order" respectively, and are added to the default simpset
  5620     as solvers.  This means that the simplifier can build transitivity chains
  5621     to solve goals from the assumptions.
  5622   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5623     of blast or auto after simplification become unnecessary because the goal
  5624     is solved by simplification already.
  5625 
  5626 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5627     all proved in axiomatic type classes for semirings, rings and fields.
  5628 
  5629 * Numerics:
  5630   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5631     now formalized using the Ring_and_Field theory mentioned above.
  5632   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5633     than before, because now they are set up once in a generic manner.
  5634   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5635     Look for the general versions in Ring_and_Field (and Power if they concern
  5636     exponentiation).
  5637 
  5638 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5639 
  5640 * Records:
  5641   - Record types are now by default printed with their type abbreviation
  5642     instead of the list of all field types. This can be configured via
  5643     the reference "print_record_type_abbr".
  5644   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5645     (not enabled by default).
  5646   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5647     EX x. x = sel r to True (not enabled by default).
  5648   - Tactic "record_split_simp_tac" to split and simplify records added.
  5649 
  5650 * 'specification' command added, allowing for definition by
  5651   specification.  There is also an 'ax_specification' command that
  5652   introduces the new constants axiomatically.
  5653 
  5654 * arith(_tac) is now able to generate counterexamples for reals as well.
  5655 
  5656 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5657 
  5658 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5659   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5660 
  5661 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5662   matrix theory to linear programming.
  5663 
  5664 * Unions and Intersections:
  5665   The latex output syntax of UN and INT has been changed
  5666   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5667   i.e. the index formulae has become a subscript.
  5668   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5669 
  5670 * Unions and Intersections over Intervals:
  5671   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5672   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5673   like in normal math, and corresponding versions for < and for intersection.
  5674 
  5675 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5676   lexicographic dictonary ordering has been added as "lexord".
  5677 
  5678 * ML: the legacy theory structures Int and List have been removed. They had
  5679   conflicted with ML Basis Library structures having the same names.
  5680 
  5681 * 'refute' command added to search for (finite) countermodels.  Only works
  5682   for a fragment of HOL.  The installation of an external SAT solver is
  5683   highly recommended.  See "HOL/Refute.thy" for details.
  5684 
  5685 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5686   formulae under an assignment of free variables to random values.
  5687   In contrast to 'refute', it can deal with inductive datatypes,
  5688   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5689   for examples.
  5690 
  5691 
  5692 *** HOLCF ***
  5693 
  5694 * Streams now come with concatenation and are part of the HOLCF image
  5695 
  5696 
  5697 
  5698 New in Isabelle2003 (May 2003)
  5699 ------------------------------
  5700 
  5701 *** General ***
  5702 
  5703 * Provers/simplifier:
  5704 
  5705   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5706     Assumptions are now subject to complete mutual simplification,
  5707     not just from left to right. The simplifier now preserves
  5708     the order of assumptions.
  5709 
  5710     Potential INCOMPATIBILITY:
  5711 
  5712     -- simp sometimes diverges where the old version did
  5713        not, e.g. invoking simp on the goal
  5714 
  5715         [| P (f x); y = x; f x = f y |] ==> Q
  5716 
  5717        now gives rise to the infinite reduction sequence
  5718 
  5719         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5720 
  5721        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5722        kind of problem.
  5723 
  5724     -- Tactics combining classical reasoner and simplification (such as auto)
  5725        are also affected by this change, because many of them rely on
  5726        simp. They may sometimes diverge as well or yield a different numbers
  5727        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5728        in case of problems. Sometimes subsequent calls to the classical
  5729        reasoner will fail because a preceeding call to the simplifier too
  5730        eagerly simplified the goal, e.g. deleted redundant premises.
  5731 
  5732   - The simplifier trace now shows the names of the applied rewrite rules
  5733 
  5734   - You can limit the number of recursive invocations of the simplifier
  5735     during conditional rewriting (where the simplifie tries to solve the
  5736     conditions before applying the rewrite rule):
  5737     ML "simp_depth_limit := n"
  5738     where n is an integer. Thus you can force termination where previously
  5739     the simplifier would diverge.
  5740 
  5741   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5742 
  5743   - No longer aborts on failed congruence proof.  Instead, the
  5744     congruence is ignored.
  5745 
  5746 * Pure: New generic framework for extracting programs from constructive
  5747   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5748   as HOL/Extraction for some case studies.
  5749 
  5750 * Pure: The main goal of the proof state is no longer shown by default, only
  5751 the subgoals. This behaviour is controlled by a new flag.
  5752    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5753 (ML: Proof.show_main_goal).
  5754 
  5755 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5756 rules whose conclusion matches subgoal 1:
  5757       PG menu: Isabelle/Isar -> Show me -> matching rules
  5758 The rules are ordered by how closely they match the subgoal.
  5759 In particular, rules that solve a subgoal outright are displayed first
  5760 (or rather last, the way they are printed).
  5761 (ML: ProofGeneral.print_intros())
  5762 
  5763 * Pure: New flag trace_unify_fail causes unification to print
  5764 diagnostic information (PG: in trace buffer) when it fails. This is
  5765 useful for figuring out why single step proofs like rule, erule or
  5766 assumption failed.
  5767 
  5768 * Pure: Locale specifications now produce predicate definitions
  5769 according to the body of text (covering assumptions modulo local
  5770 definitions); predicate "loc_axioms" covers newly introduced text,
  5771 while "loc" is cumulative wrt. all included locale expressions; the
  5772 latter view is presented only on export into the global theory
  5773 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5774 on the old view without predicates;
  5775 
  5776 * Pure: predefined locales "var" and "struct" are useful for sharing
  5777 parameters (as in CASL, for example); just specify something like
  5778 ``var x + var y + struct M'' as import;
  5779 
  5780 * Pure: improved thms_containing: proper indexing of facts instead of
  5781 raw theorems; check validity of results wrt. current name space;
  5782 include local facts of proof configuration (also covers active
  5783 locales), cover fixed variables in index; may use "_" in term
  5784 specification; an optional limit for the number of printed facts may
  5785 be given (the default is 40);
  5786 
  5787 * Pure: disallow duplicate fact bindings within new-style theory files
  5788 (batch-mode only);
  5789 
  5790 * Provers: improved induct method: assumptions introduced by case
  5791 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5792 the goal statement); "foo" still refers to all facts collectively;
  5793 
  5794 * Provers: the function blast.overloaded has been removed: all constants
  5795 are regarded as potentially overloaded, which improves robustness in exchange
  5796 for slight decrease in efficiency;
  5797 
  5798 * Provers/linorder: New generic prover for transitivity reasoning over
  5799 linear orders.  Note: this prover is not efficient!
  5800 
  5801 * Isar: preview of problems to finish 'show' now produce an error
  5802 rather than just a warning (in interactive mode);
  5803 
  5804 
  5805 *** HOL ***
  5806 
  5807 * arith(_tac)
  5808 
  5809  - Produces a counter example if it cannot prove a goal.
  5810    Note that the counter example may be spurious if the goal is not a formula
  5811    of quantifier-free linear arithmetic.
  5812    In ProofGeneral the counter example appears in the trace buffer.
  5813 
  5814  - Knows about div k and mod k where k is a numeral of type nat or int.
  5815 
  5816  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  5817    linear arithmetic fails. This takes account of quantifiers and divisibility.
  5818    Presburger arithmetic can also be called explicitly via presburger(_tac).
  5819 
  5820 * simp's arithmetic capabilities have been enhanced a bit: it now
  5821 takes ~= in premises into account (by performing a case split);
  5822 
  5823 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  5824 are distributed over a sum of terms;
  5825 
  5826 * New tactic "trans_tac" and method "trans" instantiate
  5827 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  5828 "<=", "<" and "=").
  5829 
  5830 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  5831 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  5832 
  5833 * 'typedef' command has new option "open" to suppress the set
  5834 definition;
  5835 
  5836 * functions Min and Max on finite sets have been introduced (theory
  5837 Finite_Set);
  5838 
  5839 * attribute [symmetric] now works for relations as well; it turns
  5840 (x,y) : R^-1 into (y,x) : R, and vice versa;
  5841 
  5842 * induct over a !!-quantified statement (say !!x1..xn):
  5843   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  5844 
  5845 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  5846 %x. None. Warning: empty_def now refers to the previously hidden definition
  5847 of the empty set.
  5848 
  5849 * Algebra: formalization of classical algebra.  Intended as base for
  5850 any algebraic development in Isabelle.  Currently covers group theory
  5851 (up to Sylow's theorem) and ring theory (Universal Property of
  5852 Univariate Polynomials).  Contributions welcome;
  5853 
  5854 * GroupTheory: deleted, since its material has been moved to Algebra;
  5855 
  5856 * Complex: new directory of the complex numbers with numeric constants,
  5857 nonstandard complex numbers, and some complex analysis, standard and
  5858 nonstandard (Jacques Fleuriot);
  5859 
  5860 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  5861 
  5862 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  5863 Fleuriot);
  5864 
  5865 * Real/HahnBanach: updated and adapted to locales;
  5866 
  5867 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  5868 Gray and Kramer);
  5869 
  5870 * UNITY: added the Meier-Sanders theory of progress sets;
  5871 
  5872 * MicroJava: bytecode verifier and lightweight bytecode verifier
  5873 as abstract algorithms, instantiated to the JVM;
  5874 
  5875 * Bali: Java source language formalization. Type system, operational
  5876 semantics, axiomatic semantics. Supported language features:
  5877 classes, interfaces, objects,virtual methods, static methods,
  5878 static/instance fields, arrays, access modifiers, definite
  5879 assignment, exceptions.
  5880 
  5881 
  5882 *** ZF ***
  5883 
  5884 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  5885 universe, etc.);
  5886 
  5887 * Main ZF: virtually all theories converted to new-style format;
  5888 
  5889 
  5890 *** ML ***
  5891 
  5892 * Pure: Tactic.prove provides sane interface for internal proofs;
  5893 omits the infamous "standard" operation, so this is more appropriate
  5894 than prove_goalw_cterm in many situations (e.g. in simprocs);
  5895 
  5896 * Pure: improved error reporting of simprocs;
  5897 
  5898 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  5899 up simprocs;
  5900 
  5901 
  5902 *** Document preparation ***
  5903 
  5904 * uses \par instead of \\ for line breaks in theory text. This may
  5905 shift some page breaks in large documents. To get the old behaviour
  5906 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  5907 
  5908 * minimized dependencies of isabelle.sty and isabellesym.sty on
  5909 other packages
  5910 
  5911 * \<euro> now needs package babel/greek instead of marvosym (which
  5912 broke \Rightarrow)
  5913 
  5914 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  5915 textcomp package)
  5916 
  5917 
  5918 
  5919 New in Isabelle2002 (March 2002)
  5920 --------------------------------
  5921 
  5922 *** Document preparation ***
  5923 
  5924 * greatly simplified document preparation setup, including more
  5925 graceful interpretation of isatool usedir -i/-d/-D options, and more
  5926 instructive isatool mkdir; users should basically be able to get
  5927 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  5928 users may run a separate document processing stage manually like this:
  5929 "isatool usedir -D output HOL Test && isatool document Test/output";
  5930 
  5931 * theory dependency graph may now be incorporated into documents;
  5932 isatool usedir -g true will produce session_graph.eps/.pdf for use
  5933 with \includegraphics of LaTeX;
  5934 
  5935 * proper spacing of consecutive markup elements, especially text
  5936 blocks after section headings;
  5937 
  5938 * support bold style (for single symbols only), input syntax is like
  5939 this: "\<^bold>\<alpha>" or "\<^bold>A";
  5940 
  5941 * \<bullet> is now output as bold \cdot by default, which looks much
  5942 better in printed text;
  5943 
  5944 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  5945 note that these symbols are currently unavailable in Proof General /
  5946 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  5947 
  5948 * isatool latex no longer depends on changed TEXINPUTS, instead
  5949 isatool document copies the Isabelle style files to the target
  5950 location;
  5951 
  5952 
  5953 *** Isar ***
  5954 
  5955 * Pure/Provers: improved proof by cases and induction;
  5956   - 'case' command admits impromptu naming of parameters (such as
  5957     "case (Suc n)");
  5958   - 'induct' method divinates rule instantiation from the inductive
  5959     claim; no longer requires excessive ?P bindings for proper
  5960     instantiation of cases;
  5961   - 'induct' method properly enumerates all possibilities of set/type
  5962     rules; as a consequence facts may be also passed through *type*
  5963     rules without further ado;
  5964   - 'induct' method now derives symbolic cases from the *rulified*
  5965     rule (before it used to rulify cases stemming from the internal
  5966     atomized version); this means that the context of a non-atomic
  5967     statement becomes is included in the hypothesis, avoiding the
  5968     slightly cumbersome show "PROP ?case" form;
  5969   - 'induct' may now use elim-style induction rules without chaining
  5970     facts, using ``missing'' premises from the goal state; this allows
  5971     rules stemming from inductive sets to be applied in unstructured
  5972     scripts, while still benefitting from proper handling of non-atomic
  5973     statements; NB: major inductive premises need to be put first, all
  5974     the rest of the goal is passed through the induction;
  5975   - 'induct' proper support for mutual induction involving non-atomic
  5976     rule statements (uses the new concept of simultaneous goals, see
  5977     below);
  5978   - append all possible rule selections, but only use the first
  5979     success (no backtracking);
  5980   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  5981   - undeclared rule case names default to numbers 1, 2, 3, ...;
  5982   - added 'print_induct_rules' (covered by help item in recent Proof
  5983     General versions);
  5984   - moved induct/cases attributes to Pure, methods to Provers;
  5985   - generic method setup instantiated for FOL and HOL;
  5986 
  5987 * Pure: support multiple simultaneous goal statements, for example
  5988 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  5989 meta-level mechanism, this acts as if several individual goals had
  5990 been stated separately; in particular common proof methods need to be
  5991 repeated in order to cover all claims; note that a single elimination
  5992 step is *not* sufficient to establish the two conjunctions, so this
  5993 fails:
  5994 
  5995   assume "A & B" then have A and B ..   (*".." fails*)
  5996 
  5997 better use "obtain" in situations as above; alternative refer to
  5998 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  5999 
  6000 * Pure: proper integration with ``locales''; unlike the original
  6001 version by Florian Kammller, Isar locales package high-level proof
  6002 contexts rather than raw logical ones (e.g. we admit to include
  6003 attributes everywhere); operations on locales include merge and
  6004 rename; support for implicit arguments (``structures''); simultaneous
  6005 type-inference over imports and text; see also HOL/ex/Locales.thy for
  6006 some examples;
  6007 
  6008 * Pure: the following commands have been ``localized'', supporting a
  6009 target locale specification "(in name)": 'lemma', 'theorem',
  6010 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  6011 stored both within the locale and at the theory level (exported and
  6012 qualified by the locale name);
  6013 
  6014 * Pure: theory goals may now be specified in ``long'' form, with
  6015 ad-hoc contexts consisting of arbitrary locale elements. for example
  6016 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  6017 definitions may be given, too); the result is a meta-level rule with
  6018 the context elements being discharged in the obvious way;
  6019 
  6020 * Pure: new proof command 'using' allows to augment currently used
  6021 facts after a goal statement ('using' is syntactically analogous to
  6022 'apply', but acts on the goal's facts only); this allows chained facts
  6023 to be separated into parts given before and after a claim, as in
  6024 ``from a and b have C using d and e <proof>'';
  6025 
  6026 * Pure: renamed "antecedent" case to "rule_context";
  6027 
  6028 * Pure: new 'judgment' command records explicit information about the
  6029 object-logic embedding (used by several tools internally); no longer
  6030 use hard-wired "Trueprop";
  6031 
  6032 * Pure: added 'corollary' command;
  6033 
  6034 * Pure: fixed 'token_translation' command;
  6035 
  6036 * Pure: removed obsolete 'exported' attribute;
  6037 
  6038 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  6039 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  6040 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  6041 
  6042 * Pure: method 'atomize' presents local goal premises as object-level
  6043 statements (atomic meta-level propositions); setup controlled via
  6044 rewrite rules declarations of 'atomize' attribute; example
  6045 application: 'induct' method with proper rule statements in improper
  6046 proof *scripts*;
  6047 
  6048 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  6049 now consider the syntactic context of assumptions, giving a better
  6050 chance to get type-inference of the arguments right (this is
  6051 especially important for locales);
  6052 
  6053 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  6054 mode;
  6055 
  6056 * Pure/obtain: the formal conclusion "thesis", being marked as
  6057 ``internal'', may no longer be reference directly in the text;
  6058 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  6059 situations;
  6060 
  6061 * Pure: generic 'sym' attribute which declares a rule both as pure
  6062 'elim?' and for the 'symmetric' operation;
  6063 
  6064 * Pure: marginal comments ``--'' may now occur just anywhere in the
  6065 text; the fixed correlation with particular command syntax has been
  6066 discontinued;
  6067 
  6068 * Pure: new method 'rules' is particularly well-suited for proof
  6069 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  6070 but often produces more compact proof terms with less detours;
  6071 
  6072 * Pure/Provers/classical: simplified integration with pure rule
  6073 attributes and methods; the classical "intro?/elim?/dest?"
  6074 declarations coincide with the pure ones; the "rule" method no longer
  6075 includes classically swapped intros; "intro" and "elim" methods no
  6076 longer pick rules from the context; also got rid of ML declarations
  6077 AddXIs/AddXEs/AddXDs; all of this has some potential for
  6078 INCOMPATIBILITY;
  6079 
  6080 * Provers/classical: attribute 'swapped' produces classical inversions
  6081 of introduction rules;
  6082 
  6083 * Provers/simplifier: 'simplified' attribute may refer to explicit
  6084 rules instead of full simplifier context; 'iff' attribute handles
  6085 conditional rules;
  6086 
  6087 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  6088 
  6089 * HOL: 'recdef' now fails on unfinished automated proofs, use
  6090 "(permissive)" option to recover old behavior;
  6091 
  6092 * HOL: 'inductive' no longer features separate (collective) attributes
  6093 for 'intros' (was found too confusing);
  6094 
  6095 * HOL: properly declared induction rules less_induct and
  6096 wf_induct_rule;
  6097 
  6098 
  6099 *** HOL ***
  6100 
  6101 * HOL: moved over to sane numeral syntax; the new policy is as
  6102 follows:
  6103 
  6104   - 0 and 1 are polymorphic constants, which are defined on any
  6105   numeric type (nat, int, real etc.);
  6106 
  6107   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  6108   binary representation internally;
  6109 
  6110   - type nat has special constructor Suc, and generally prefers Suc 0
  6111   over 1::nat and Suc (Suc 0) over 2::nat;
  6112 
  6113 This change may cause significant problems of INCOMPATIBILITY; here
  6114 are some hints on converting existing sources:
  6115 
  6116   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  6117   entities, so expressions involving "-" (unary or binary minus) need
  6118   to be spaced properly;
  6119 
  6120   - existing occurrences of "1" may need to be constraint "1::nat" or
  6121   even replaced by Suc 0; similar for old "2";
  6122 
  6123   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  6124 
  6125   - remove all special provisions on numerals in proofs;
  6126 
  6127 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  6128 representation (depends on bin_arith_simps in the default context);
  6129 
  6130 * HOL: symbolic syntax for x^2 (numeral 2);
  6131 
  6132 * HOL: the class of all HOL types is now called "type" rather than
  6133 "term"; INCOMPATIBILITY, need to adapt references to this type class
  6134 in axclass/classes, instance/arities, and (usually rare) occurrences
  6135 in typings (of consts etc.); internally the class is called
  6136 "HOL.type", ML programs should refer to HOLogic.typeS;
  6137 
  6138 * HOL/record package improvements:
  6139   - new derived operations "fields" to build a partial record section,
  6140     "extend" to promote a fixed record to a record scheme, and
  6141     "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*
  6142     declared as simp by default;
  6143   - shared operations ("more", "fields", etc.) now need to be always
  6144     qualified) --- potential INCOMPATIBILITY;
  6145   - removed "make_scheme" operations (use "make" with "extend") --
  6146     INCOMPATIBILITY;
  6147   - removed "more" class (simply use "term") -- INCOMPATIBILITY;
  6148   - provides cases/induct rules for use with corresponding Isar
  6149     methods (for concrete records, record schemes, concrete more
  6150     parts, and schematic more parts -- in that order);
  6151   - internal definitions directly based on a light-weight abstract
  6152     theory of product types over typedef rather than datatype;
  6153 
  6154 * HOL: generic code generator for generating executable ML code from
  6155 specifications; specific support for HOL constructs such as inductive
  6156 datatypes and sets, as well as recursive functions; can be invoked
  6157 via 'generate_code' theory section;
  6158 
  6159 * HOL: canonical cases/induct rules for n-tuples (n = 3..7);
  6160 
  6161 * HOL: consolidated and renamed several theories.  In particular:
  6162         Ord.thy has been absorbed into HOL.thy
  6163         String.thy has been absorbed into List.thy
  6164 
  6165 * HOL: concrete setsum syntax "\<Sum>i:A. b" == "setsum (%i. b) A"
  6166 (beware of argument permutation!);
  6167 
  6168 * HOL: linorder_less_split superseded by linorder_cases;
  6169 
  6170 * HOL/List: "nodups" renamed to "distinct";
  6171 
  6172 * HOL: added "The" definite description operator; move Hilbert's "Eps"
  6173 to peripheral theory "Hilbert_Choice"; some INCOMPATIBILITIES:
  6174   - Ex_def has changed, now need to use some_eq_ex
  6175 
  6176 * HOL: made split_all_tac safe; EXISTING PROOFS MAY FAIL OR LOOP, so
  6177 in this (rare) case use:
  6178 
  6179   delSWrapper "split_all_tac"
  6180   addSbefore ("unsafe_split_all_tac", unsafe_split_all_tac)
  6181 
  6182 * HOL: added safe wrapper "split_conv_tac" to claset; EXISTING PROOFS
  6183 MAY FAIL;
  6184 
  6185 * HOL: introduced f^n = f o ... o f; warning: due to the limits of
  6186 Isabelle's type classes, ^ on functions and relations has too general
  6187 a domain, namely ('a * 'b) set and 'a => 'b; this means that it may be
  6188 necessary to attach explicit type constraints;
  6189 
  6190 * HOL/Relation: the prefix name of the infix "O" has been changed from
  6191 "comp" to "rel_comp"; INCOMPATIBILITY: a few theorems have been
  6192 renamed accordingly (eg "compI" -> "rel_compI").
  6193 
  6194 * HOL: syntax translations now work properly with numerals and records
  6195 expressions;
  6196 
  6197 * HOL: bounded abstraction now uses syntax "%" / "\<lambda>" instead
  6198 of "lam" -- INCOMPATIBILITY;
  6199 
  6200 * HOL: got rid of some global declarations (potential INCOMPATIBILITY
  6201 for ML tools): const "()" renamed "Product_Type.Unity", type "unit"
  6202 renamed "Product_Type.unit";
  6203 
  6204 * HOL: renamed rtrancl_into_rtrancl2 to converse_rtrancl_into_rtrancl
  6205 
  6206 * HOL: removed obsolete theorem "optionE" (use "option.exhaust", or
  6207 the "cases" method);
  6208 
  6209 * HOL/GroupTheory: group theory examples including Sylow's theorem (by
  6210 Florian Kammller);
  6211 
  6212 * HOL/IMP: updated and converted to new-style theory format; several
  6213 parts turned into readable document, with proper Isar proof texts and
  6214 some explanations (by Gerwin Klein);
  6215 
  6216 * HOL-Real: added Complex_Numbers (by Gertrud Bauer);
  6217 
  6218 * HOL-Hyperreal is now a logic image;
  6219 
  6220 
  6221 *** HOLCF ***
  6222 
  6223 * Isar: consts/constdefs supports mixfix syntax for continuous
  6224 operations;
  6225 
  6226 * Isar: domain package adapted to new-style theory format, e.g. see
  6227 HOLCF/ex/Dnat.thy;
  6228 
  6229 * theory Lift: proper use of rep_datatype lift instead of ML hacks --
  6230 potential INCOMPATIBILITY; now use plain induct_tac instead of former
  6231 lift.induct_tac, always use UU instead of Undef;
  6232 
  6233 * HOLCF/IMP: updated and converted to new-style theory;
  6234