NEWS
author blanchet
Thu, 17 Mar 2011 22:07:17 +0100
changeset 42864 bd6296de1432
parent 42826 703ea96b13c6
child 42870 3c029ef9e0f2
permissions -rw-r--r--
reintroduced "show_skolems" option -- useful when too many Skolems are displayed
     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 * Function package: discontinued option "tailrec".
    54 INCOMPATIBILITY. Use partial_function instead.
    55 
    56 
    57 *** Document preparation ***
    58 
    59 * New term style "isub" as ad-hoc conversion of variables x1, y23 into
    60 subscripted form x\<^isub>1, y\<^isub>2\<^isub>3.
    61 
    62 
    63 *** ML ***
    64 
    65 * Path.print is the official way to show file-system paths to users
    66 (including quotes etc.).
    67 
    68 
    69 
    70 New in Isabelle2011 (January 2011)
    71 ----------------------------------
    72 
    73 *** General ***
    74 
    75 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
    76 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
    77 useful tooltips and hyperlinks produced from its static analysis.  The
    78 bundled component provides an executable Isabelle tool that can be run
    79 like this:
    80 
    81   Isabelle2011/bin/isabelle jedit
    82 
    83 * Significantly improved Isabelle/Isar implementation manual.
    84 
    85 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
    86 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
    87 while the default heap location within that directory lacks that extra
    88 suffix.  This isolates multiple Isabelle installations from each
    89 other, avoiding problems with old settings in new versions.
    90 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
    91 
    92 * Source files are always encoded as UTF-8, instead of old-fashioned
    93 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
    94 the following package declarations:
    95 
    96   \usepackage[utf8]{inputenc}
    97   \usepackage{textcomp}
    98 
    99 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
   100 a Unicode character is treated as a single symbol, not a sequence of
   101 non-ASCII bytes as before.  Since Isabelle/ML string literals may
   102 contain symbols without further backslash escapes, Unicode can now be
   103 used here as well.  Recall that Symbol.explode in ML provides a
   104 consistent view on symbols, while raw explode (or String.explode)
   105 merely give a byte-oriented representation.
   106 
   107 * Theory loader: source files are primarily located via the master
   108 directory of each theory node (where the .thy file itself resides).
   109 The global load path is still partially available as legacy feature.
   110 Minor INCOMPATIBILITY due to subtle change in file lookup: use
   111 explicit paths, relatively to the theory.
   112 
   113 * Special treatment of ML file names has been discontinued.
   114 Historically, optional extensions .ML or .sml were added on demand --
   115 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
   116 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
   117 
   118 * Various options that affect pretty printing etc. are now properly
   119 handled within the context via configuration options, instead of
   120 unsynchronized references or print modes.  There are both ML Config.T
   121 entities and Isar declaration attributes to access these.
   122 
   123   ML (Config.T)                 Isar (attribute)
   124 
   125   eta_contract                  eta_contract
   126   show_brackets                 show_brackets
   127   show_sorts                    show_sorts
   128   show_types                    show_types
   129   show_question_marks           show_question_marks
   130   show_consts                   show_consts
   131   show_abbrevs                  show_abbrevs
   132 
   133   Syntax.ast_trace              syntax_ast_trace
   134   Syntax.ast_stat               syntax_ast_stat
   135   Syntax.ambiguity_level        syntax_ambiguity_level
   136 
   137   Goal_Display.goals_limit      goals_limit
   138   Goal_Display.show_main_goal   show_main_goal
   139 
   140   Method.rule_trace             rule_trace
   141 
   142   Thy_Output.display            thy_output_display
   143   Thy_Output.quotes             thy_output_quotes
   144   Thy_Output.indent             thy_output_indent
   145   Thy_Output.source             thy_output_source
   146   Thy_Output.break              thy_output_break
   147 
   148 Note that corresponding "..._default" references in ML may only be
   149 changed globally at the ROOT session setup, but *not* within a theory.
   150 The option "show_abbrevs" supersedes the former print mode
   151 "no_abbrevs" with inverted meaning.
   152 
   153 * More systematic naming of some configuration options.
   154 INCOMPATIBILITY.
   155 
   156   trace_simp  ~>  simp_trace
   157   debug_simp  ~>  simp_debug
   158 
   159 * Support for real valued configuration options, using simplistic
   160 floating-point notation that coincides with the inner syntax for
   161 float_token.
   162 
   163 * Support for real valued preferences (with approximative PGIP type):
   164 front-ends need to accept "pgint" values in float notation.
   165 INCOMPATIBILITY.
   166 
   167 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
   168 DejaVu Sans.
   169 
   170 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   171 
   172 
   173 *** Pure ***
   174 
   175 * Command 'type_synonym' (with single argument) replaces somewhat
   176 outdated 'types', which is still available as legacy feature for some
   177 time.
   178 
   179 * Command 'nonterminal' (with 'and' separated list of arguments)
   180 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
   181 
   182 * Command 'notepad' replaces former 'example_proof' for
   183 experimentation in Isar without any result.  INCOMPATIBILITY.
   184 
   185 * Locale interpretation commands 'interpret' and 'sublocale' accept
   186 lists of equations to map definitions in a locale to appropriate
   187 entities in the context of the interpretation.  The 'interpretation'
   188 command already provided this functionality.
   189 
   190 * Diagnostic command 'print_dependencies' prints the locale instances
   191 that would be activated if the specified expression was interpreted in
   192 the current context.  Variant "print_dependencies!" assumes a context
   193 without interpretations.
   194 
   195 * Diagnostic command 'print_interps' prints interpretations in proofs
   196 in addition to interpretations in theories.
   197 
   198 * Discontinued obsolete 'global' and 'local' commands to manipulate
   199 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
   200 Sign.root_path and Sign.local_path may be applied directly where this
   201 feature is still required for historical reasons.
   202 
   203 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
   204 'definition' instead.
   205 
   206 * The "prems" fact, which refers to the accidental collection of
   207 foundational premises in the context, is now explicitly marked as
   208 legacy feature and will be discontinued soon.  Consider using "assms"
   209 of the head statement or reference facts by explicit names.
   210 
   211 * Document antiquotations @{class} and @{type} print classes and type
   212 constructors.
   213 
   214 * Document antiquotation @{file} checks file/directory entries within
   215 the local file system.
   216 
   217 
   218 *** HOL ***
   219 
   220 * Coercive subtyping: functions can be declared as coercions and type
   221 inference will add them as necessary upon input of a term.  Theory
   222 Complex_Main declares real :: nat => real and real :: int => real as
   223 coercions. A coercion function f is declared like this:
   224 
   225   declare [[coercion f]]
   226 
   227 To lift coercions through type constructors (e.g. from nat => real to
   228 nat list => real list), map functions can be declared, e.g.
   229 
   230   declare [[coercion_map map]]
   231 
   232 Currently coercion inference is activated only in theories including
   233 real numbers, i.e. descendants of Complex_Main.  This is controlled by
   234 the configuration option "coercion_enabled", e.g. it can be enabled in
   235 other theories like this:
   236 
   237   declare [[coercion_enabled]]
   238 
   239 * Command 'partial_function' provides basic support for recursive
   240 function definitions over complete partial orders.  Concrete instances
   241 are provided for i) the option type, ii) tail recursion on arbitrary
   242 types, and iii) the heap monad of Imperative_HOL.  See
   243 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
   244 for examples.
   245 
   246 * Function package: f.psimps rules are no longer implicitly declared
   247 as [simp].  INCOMPATIBILITY.
   248 
   249 * Datatype package: theorems generated for executable equality (class
   250 "eq") carry proper names and are treated as default code equations.
   251 
   252 * Inductive package: now offers command 'inductive_simps' to
   253 automatically derive instantiated and simplified equations for
   254 inductive predicates, similar to 'inductive_cases'.
   255 
   256 * Command 'enriched_type' allows to register properties of the
   257 functorial structure of types.
   258 
   259 * Improved infrastructure for term evaluation using code generator
   260 techniques, in particular static evaluation conversions.
   261 
   262 * Code generator: Scala (2.8 or higher) has been added to the target
   263 languages.
   264 
   265 * Code generator: globbing constant expressions "*" and "Theory.*"
   266 have been replaced by the more idiomatic "_" and "Theory._".
   267 INCOMPATIBILITY.
   268 
   269 * Code generator: export_code without explicit file declaration prints
   270 to standard output.  INCOMPATIBILITY.
   271 
   272 * Code generator: do not print function definitions for case
   273 combinators any longer.
   274 
   275 * Code generator: simplification with rules determined with
   276 src/Tools/Code/code_simp.ML and method "code_simp".
   277 
   278 * Code generator for records: more idiomatic representation of record
   279 types.  Warning: records are not covered by ancient SML code
   280 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
   281 rep_datatype declaration helps to succeed then:
   282 
   283   record 'a foo = ...
   284   ...
   285   rep_datatype foo_ext ...
   286 
   287 * Records: logical foundation type for records does not carry a
   288 '_type' suffix any longer (obsolete due to authentic syntax).
   289 INCOMPATIBILITY.
   290 
   291 * Quickcheck now by default uses exhaustive testing instead of random
   292 testing.  Random testing can be invoked by "quickcheck [random]",
   293 exhaustive testing by "quickcheck [exhaustive]".
   294 
   295 * Quickcheck instantiates polymorphic types with small finite
   296 datatypes by default. This enables a simple execution mechanism to
   297 handle quantifiers and function equality over the finite datatypes.
   298 
   299 * Quickcheck random generator has been renamed from "code" to
   300 "random".  INCOMPATIBILITY.
   301 
   302 * Quickcheck now has a configurable time limit which is set to 30
   303 seconds by default. This can be changed by adding [timeout = n] to the
   304 quickcheck command. The time limit for Auto Quickcheck is still set
   305 independently.
   306 
   307 * Quickcheck in locales considers interpretations of that locale for
   308 counter example search.
   309 
   310 * Sledgehammer:
   311   - Added "smt" and "remote_smt" provers based on the "smt" proof
   312     method. See the Sledgehammer manual for details ("isabelle doc
   313     sledgehammer").
   314   - Renamed commands:
   315     sledgehammer atp_info ~> sledgehammer running_provers
   316     sledgehammer atp_kill ~> sledgehammer kill_provers
   317     sledgehammer available_atps ~> sledgehammer available_provers
   318     INCOMPATIBILITY.
   319   - Renamed options:
   320     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
   321     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
   322     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
   323     (and "ms" and "min" are no longer supported)
   324     INCOMPATIBILITY.
   325 
   326 * Nitpick:
   327   - Renamed options:
   328     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
   329     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
   330     INCOMPATIBILITY.
   331   - Added support for partial quotient types.
   332   - Added local versions of the "Nitpick.register_xxx" functions.
   333   - Added "whack" option.
   334   - Allow registration of quotient types as codatatypes.
   335   - Improved "merge_type_vars" option to merge more types.
   336   - Removed unsound "fast_descrs" option.
   337   - Added custom symmetry breaking for datatypes, making it possible to reach
   338     higher cardinalities.
   339   - Prevent the expansion of too large definitions.
   340 
   341 * Proof methods "metis" and "meson" now have configuration options
   342 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
   343 to diagnose these tools. E.g.
   344 
   345     using [[metis_trace = true]]
   346 
   347 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
   348 manually as command 'solve_direct'.
   349 
   350 * The default SMT solver Z3 must be enabled explicitly (due to
   351 licensing issues) by setting the environment variable
   352 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
   353 commercial applications, the SMT solver CVC3 is provided as fall-back;
   354 changing the SMT solver is done via the configuration option
   355 "smt_solver".
   356 
   357 * Remote SMT solvers need to be referred to by the "remote_" prefix,
   358 i.e. "remote_cvc3" and "remote_z3".
   359 
   360 * Added basic SMT support for datatypes, records, and typedefs using
   361 the oracle mode (no proofs).  Direct support of pairs has been dropped
   362 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
   363 support for a similar behavior).  Minor INCOMPATIBILITY.
   364 
   365 * Changed SMT configuration options:
   366   - Renamed:
   367     z3_proofs ~> smt_oracle (with inverted meaning)
   368     z3_trace_assms ~> smt_trace_used_facts
   369     INCOMPATIBILITY.
   370   - Added:
   371     smt_verbose
   372     smt_random_seed
   373     smt_datatypes
   374     smt_infer_triggers
   375     smt_monomorph_limit
   376     cvc3_options
   377     remote_cvc3_options
   378     remote_z3_options
   379     yices_options
   380 
   381 * Boogie output files (.b2i files) need to be declared in the theory
   382 header.
   383 
   384 * Simplification procedure "list_to_set_comprehension" rewrites list
   385 comprehensions applied to List.set to set comprehensions.  Occasional
   386 INCOMPATIBILITY, may be deactivated like this:
   387 
   388   declare [[simproc del: list_to_set_comprehension]]
   389 
   390 * Removed old version of primrec package.  INCOMPATIBILITY.
   391 
   392 * Removed simplifier congruence rule of "prod_case", as has for long
   393 been the case with "split".  INCOMPATIBILITY.
   394 
   395 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
   396 
   397 * Removed [split_format ... and ... and ...] version of
   398 [split_format].  Potential INCOMPATIBILITY.
   399 
   400 * Predicate "sorted" now defined inductively, with nice induction
   401 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
   402 
   403 * Constant "contents" renamed to "the_elem", to free the generic name
   404 contents for other uses.  INCOMPATIBILITY.
   405 
   406 * Renamed class eq and constant eq (for code generation) to class
   407 equal and constant equal, plus renaming of related facts and various
   408 tuning.  INCOMPATIBILITY.
   409 
   410 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
   411 
   412 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
   413 INCOMPATIBILITY.
   414 
   415 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
   416 avoid confusion with finite sets.  INCOMPATIBILITY.
   417 
   418 * Abandoned locales equiv, congruent and congruent2 for equivalence
   419 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
   420 for congruent(2)).
   421 
   422 * Some previously unqualified names have been qualified:
   423 
   424   types
   425     bool ~> HOL.bool
   426     nat ~> Nat.nat
   427 
   428   constants
   429     Trueprop ~> HOL.Trueprop
   430     True ~> HOL.True
   431     False ~> HOL.False
   432     op & ~> HOL.conj
   433     op | ~> HOL.disj
   434     op --> ~> HOL.implies
   435     op = ~> HOL.eq
   436     Not ~> HOL.Not
   437     The ~> HOL.The
   438     All ~> HOL.All
   439     Ex ~> HOL.Ex
   440     Ex1 ~> HOL.Ex1
   441     Let ~> HOL.Let
   442     If ~> HOL.If
   443     Ball ~> Set.Ball
   444     Bex ~> Set.Bex
   445     Suc ~> Nat.Suc
   446     Pair ~> Product_Type.Pair
   447     fst ~> Product_Type.fst
   448     snd ~> Product_Type.snd
   449     curry ~> Product_Type.curry
   450     op : ~> Set.member
   451     Collect ~> Set.Collect
   452 
   453 INCOMPATIBILITY.
   454 
   455 * More canonical naming convention for some fundamental definitions:
   456 
   457     bot_bool_eq ~> bot_bool_def
   458     top_bool_eq ~> top_bool_def
   459     inf_bool_eq ~> inf_bool_def
   460     sup_bool_eq ~> sup_bool_def
   461     bot_fun_eq  ~> bot_fun_def
   462     top_fun_eq  ~> top_fun_def
   463     inf_fun_eq  ~> inf_fun_def
   464     sup_fun_eq  ~> sup_fun_def
   465 
   466 INCOMPATIBILITY.
   467 
   468 * More stylized fact names:
   469 
   470   expand_fun_eq ~> fun_eq_iff
   471   expand_set_eq ~> set_eq_iff
   472   set_ext       ~> set_eqI
   473   nat_number    ~> eval_nat_numeral
   474 
   475 INCOMPATIBILITY.
   476 
   477 * Refactoring of code-generation specific operations in theory List:
   478 
   479   constants
   480     null ~> List.null
   481 
   482   facts
   483     mem_iff ~> member_def
   484     null_empty ~> null_def
   485 
   486 INCOMPATIBILITY.  Note that these were not supposed to be used
   487 regularly unless for striking reasons; their main purpose was code
   488 generation.
   489 
   490 Various operations from the Haskell prelude are used for generating
   491 Haskell code.
   492 
   493 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
   494 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
   495 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
   496 
   497 * Abolished some non-alphabetic type names: "prod" and "sum" replace
   498 "*" and "+" respectively.  INCOMPATIBILITY.
   499 
   500 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
   501 "Sum_Type.Plus" instead.
   502 
   503 * Constant "split" has been merged with constant "prod_case"; names of
   504 ML functions, facts etc. involving split have been retained so far,
   505 though.  INCOMPATIBILITY.
   506 
   507 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
   508 instead.  INCOMPATIBILITY.
   509 
   510 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
   511 INCOMPATIBILITY.
   512 
   513 * Former theory Library/Enum is now part of the HOL-Main image.
   514 INCOMPATIBILITY: all constants of the Enum theory now have to be
   515 referred to by its qualified name.
   516 
   517   enum    ~>  Enum.enum
   518   nlists  ~>  Enum.nlists
   519   product ~>  Enum.product
   520 
   521 * Theory Library/Monad_Syntax provides do-syntax for monad types.
   522 Syntax in Library/State_Monad has been changed to avoid ambiguities.
   523 INCOMPATIBILITY.
   524 
   525 * Theory Library/SetsAndFunctions has been split into
   526 Library/Function_Algebras and Library/Set_Algebras; canonical names
   527 for instance definitions for functions; various improvements.
   528 INCOMPATIBILITY.
   529 
   530 * Theory Library/Multiset provides stable quicksort implementation of
   531 sort_key.
   532 
   533 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
   534 INCOMPATIBILITY.
   535 
   536 * Session Multivariate_Analysis: introduced a type class for euclidean
   537 space.  Most theorems are now stated in terms of euclidean spaces
   538 instead of finite cartesian products.
   539 
   540   types
   541     real ^ 'n ~>  'a::real_vector
   542               ~>  'a::euclidean_space
   543               ~>  'a::ordered_euclidean_space
   544         (depends on your needs)
   545 
   546   constants
   547      _ $ _        ~> _ $$ _
   548      \<chi> x. _  ~> \<chi>\<chi> x. _
   549      CARD('n)     ~> DIM('a)
   550 
   551 Also note that the indices are now natural numbers and not from some
   552 finite type. Finite cartesian products of euclidean spaces, products
   553 of euclidean spaces the real and complex numbers are instantiated to
   554 be euclidean_spaces.  INCOMPATIBILITY.
   555 
   556 * Session Probability: introduced pextreal as positive extended real
   557 numbers.  Use pextreal as value for measures.  Introduce the
   558 Radon-Nikodym derivative, product spaces and Fubini's theorem for
   559 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
   560 the integral in Multivariate Analysis.  INCOMPATIBILITY.
   561 
   562 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   563 INCOMPATIBILITY.
   564 
   565 * Session SPARK (with image HOL-SPARK) provides commands to load and
   566 prove verification conditions generated by the SPARK Ada program
   567 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
   568 
   569 
   570 *** HOL-Algebra ***
   571 
   572 * Theorems for additive ring operations (locale abelian_monoid and
   573 descendants) are generated by interpretation from their multiplicative
   574 counterparts.  Names (in particular theorem names) have the mandatory
   575 qualifier 'add'.  Previous theorem names are redeclared for
   576 compatibility.
   577 
   578 * Structure "int_ring" is now an abbreviation (previously a
   579 definition).  This fits more natural with advanced interpretations.
   580 
   581 
   582 *** HOLCF ***
   583 
   584 * The domain package now runs in definitional mode by default: The
   585 former command 'new_domain' is now called 'domain'.  To use the domain
   586 package in its original axiomatic mode, use 'domain (unsafe)'.
   587 INCOMPATIBILITY.
   588 
   589 * The new class "domain" is now the default sort.  Class "predomain"
   590 is an unpointed version of "domain". Theories can be updated by
   591 replacing sort annotations as shown below.  INCOMPATIBILITY.
   592 
   593   'a::type ~> 'a::countable
   594   'a::cpo  ~> 'a::predomain
   595   'a::pcpo ~> 'a::domain
   596 
   597 * The old type class "rep" has been superseded by class "domain".
   598 Accordingly, users of the definitional package must remove any
   599 "default_sort rep" declarations.  INCOMPATIBILITY.
   600 
   601 * The domain package (definitional mode) now supports unpointed
   602 predomain argument types, as long as they are marked 'lazy'. (Strict
   603 arguments must be in class "domain".) For example, the following
   604 domain definition now works:
   605 
   606   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
   607 
   608 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
   609 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
   610 'a option, and 'a list.  Additionally, it configures fixrec and the
   611 domain package to work with these types.  For example:
   612 
   613   fixrec isInl :: "('a + 'b) u -> tr"
   614     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
   615 
   616   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
   617 
   618 * The "(permissive)" option of fixrec has been replaced with a
   619 per-equation "(unchecked)" option. See
   620 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
   621 
   622 * The "bifinite" class no longer fixes a constant "approx"; the class
   623 now just asserts that such a function exists.  INCOMPATIBILITY.
   624 
   625 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
   626 defines an embedding of type 'a defl into udom by default; instances
   627 of "bifinite" and "domain" classes are available in
   628 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
   629 
   630 * The syntax "REP('a)" has been replaced with "DEFL('a)".
   631 
   632 * The predicate "directed" has been removed.  INCOMPATIBILITY.
   633 
   634 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
   635 
   636 * The function "cprod_map" has been renamed to "prod_map".
   637 INCOMPATIBILITY.
   638 
   639 * The monadic bind operator on each powerdomain has new binder syntax
   640 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
   641 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
   642 
   643 * The infix syntax for binary union on each powerdomain has changed
   644 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
   645 syntax.  INCOMPATIBILITY.
   646 
   647 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
   648 still supported as an input translation.
   649 
   650 * Renamed some theorems (the original names are also still available).
   651 
   652   expand_fun_below   ~> fun_below_iff
   653   below_fun_ext      ~> fun_belowI
   654   expand_cfun_eq     ~> cfun_eq_iff
   655   ext_cfun           ~> cfun_eqI
   656   expand_cfun_below  ~> cfun_below_iff
   657   below_cfun_ext     ~> cfun_belowI
   658   cont2cont_Rep_CFun ~> cont2cont_APP
   659 
   660 * The Abs and Rep functions for various types have changed names.
   661 Related theorem names have also changed to match. INCOMPATIBILITY.
   662 
   663   Rep_CFun  ~> Rep_cfun
   664   Abs_CFun  ~> Abs_cfun
   665   Rep_Sprod ~> Rep_sprod
   666   Abs_Sprod ~> Abs_sprod
   667   Rep_Ssum  ~> Rep_ssum
   668   Abs_Ssum  ~> Abs_ssum
   669 
   670 * Lemmas with names of the form *_defined_iff or *_strict_iff have
   671 been renamed to *_bottom_iff.  INCOMPATIBILITY.
   672 
   673 * Various changes to bisimulation/coinduction with domain package:
   674 
   675   - Definitions of "bisim" constants no longer mention definedness.
   676   - With mutual recursion, "bisim" predicate is now curried.
   677   - With mutual recursion, each type gets a separate coind theorem.
   678   - Variable names in bisim_def and coinduct rules have changed.
   679 
   680 INCOMPATIBILITY.
   681 
   682 * Case combinators generated by the domain package for type "foo" are
   683 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
   684 
   685 * Several theorems have been renamed to more accurately reflect the
   686 names of constants and types involved.  INCOMPATIBILITY.
   687 
   688   thelub_const    ~> lub_const
   689   lub_const       ~> is_lub_const
   690   thelubI         ~> lub_eqI
   691   is_lub_lub      ~> is_lubD2
   692   lubI            ~> is_lub_lub
   693   unique_lub      ~> is_lub_unique
   694   is_ub_lub       ~> is_lub_rangeD1
   695   lub_bin_chain   ~> is_lub_bin_chain
   696   lub_fun         ~> is_lub_fun
   697   thelub_fun      ~> lub_fun
   698   thelub_cfun     ~> lub_cfun
   699   thelub_Pair     ~> lub_Pair
   700   lub_cprod       ~> is_lub_prod
   701   thelub_cprod    ~> lub_prod
   702   minimal_cprod   ~> minimal_prod
   703   inst_cprod_pcpo ~> inst_prod_pcpo
   704   UU_I            ~> bottomI
   705   compact_UU      ~> compact_bottom
   706   deflation_UU    ~> deflation_bottom
   707   finite_deflation_UU ~> finite_deflation_bottom
   708 
   709 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
   710 
   711   sq_ord_less_eq_trans ~> below_eq_trans
   712   sq_ord_eq_less_trans ~> eq_below_trans
   713   refl_less            ~> below_refl
   714   trans_less           ~> below_trans
   715   antisym_less         ~> below_antisym
   716   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
   717   box_less             ~> box_below
   718   rev_trans_less       ~> rev_below_trans
   719   not_less2not_eq      ~> not_below2not_eq
   720   less_UU_iff          ~> below_UU_iff
   721   flat_less_iff        ~> flat_below_iff
   722   adm_less             ~> adm_below
   723   adm_not_less         ~> adm_not_below
   724   adm_compact_not_less ~> adm_compact_not_below
   725   less_fun_def         ~> below_fun_def
   726   expand_fun_less      ~> fun_below_iff
   727   less_fun_ext         ~> fun_belowI
   728   less_discr_def       ~> below_discr_def
   729   discr_less_eq        ~> discr_below_eq
   730   less_unit_def        ~> below_unit_def
   731   less_cprod_def       ~> below_prod_def
   732   prod_lessI           ~> prod_belowI
   733   Pair_less_iff        ~> Pair_below_iff
   734   fst_less_iff         ~> fst_below_iff
   735   snd_less_iff         ~> snd_below_iff
   736   expand_cfun_less     ~> cfun_below_iff
   737   less_cfun_ext        ~> cfun_belowI
   738   injection_less       ~> injection_below
   739   less_up_def          ~> below_up_def
   740   not_Iup_less         ~> not_Iup_below
   741   Iup_less             ~> Iup_below
   742   up_less              ~> up_below
   743   Def_inject_less_eq   ~> Def_below_Def
   744   Def_less_is_eq       ~> Def_below_iff
   745   spair_less_iff       ~> spair_below_iff
   746   less_sprod           ~> below_sprod
   747   spair_less           ~> spair_below
   748   sfst_less_iff        ~> sfst_below_iff
   749   ssnd_less_iff        ~> ssnd_below_iff
   750   fix_least_less       ~> fix_least_below
   751   dist_less_one        ~> dist_below_one
   752   less_ONE             ~> below_ONE
   753   ONE_less_iff         ~> ONE_below_iff
   754   less_sinlD           ~> below_sinlD
   755   less_sinrD           ~> below_sinrD
   756 
   757 
   758 *** FOL and ZF ***
   759 
   760 * All constant names are now qualified internally and use proper
   761 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
   762 
   763 
   764 *** ML ***
   765 
   766 * Antiquotation @{assert} inlines a function bool -> unit that raises
   767 Fail if the argument is false.  Due to inlining the source position of
   768 failed assertions is included in the error output.
   769 
   770 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
   771 text is in practice always evaluated with a stable theory checkpoint.
   772 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
   773 
   774 * Antiquotation @{theory A} refers to theory A from the ancestry of
   775 the current context, not any accidental theory loader state as before.
   776 Potential INCOMPATIBILITY, subtle change in semantics.
   777 
   778 * Syntax.pretty_priority (default 0) configures the required priority
   779 of pretty-printed output and thus affects insertion of parentheses.
   780 
   781 * Syntax.default_root (default "any") configures the inner syntax
   782 category (nonterminal symbol) for parsing of terms.
   783 
   784 * Former exception Library.UnequalLengths now coincides with
   785 ListPair.UnequalLengths.
   786 
   787 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
   788 main functionality is provided by structure Simplifier.
   789 
   790 * Renamed raw "explode" function to "raw_explode" to emphasize its
   791 meaning.  Note that internally to Isabelle, Symbol.explode is used in
   792 almost all situations.
   793 
   794 * Discontinued obsolete function sys_error and exception SYS_ERROR.
   795 See implementation manual for further details on exceptions in
   796 Isabelle/ML.
   797 
   798 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
   799 meaning.
   800 
   801 * Renamed structure PureThy to Pure_Thy and moved most of its
   802 operations to structure Global_Theory, to emphasize that this is
   803 rarely-used global-only stuff.
   804 
   805 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
   806 instead (or tracing for high-volume output).
   807 
   808 * Configuration option show_question_marks only affects regular pretty
   809 printing of types and terms, not raw Term.string_of_vname.
   810 
   811 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
   812 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
   813 @{thms} for most purposes.
   814 
   815 * ML structure Unsynchronized is never opened, not even in Isar
   816 interaction mode as before.  Old Unsynchronized.set etc. have been
   817 discontinued -- use plain := instead.  This should be *rare* anyway,
   818 since modern tools always work via official context data, notably
   819 configuration options.
   820 
   821 * Parallel and asynchronous execution requires special care concerning
   822 interrupts.  Structure Exn provides some convenience functions that
   823 avoid working directly with raw Interrupt.  User code must not absorb
   824 interrupts -- intermediate handling (for cleanup etc.) needs to be
   825 followed by re-raising of the original exception.  Another common
   826 source of mistakes are "handle _" patterns, which make the meaning of
   827 the program subject to physical effects of the environment.
   828 
   829 
   830 
   831 New in Isabelle2009-2 (June 2010)
   832 ---------------------------------
   833 
   834 *** General ***
   835 
   836 * Authentic syntax for *all* logical entities (type classes, type
   837 constructors, term constants): provides simple and robust
   838 correspondence between formal entities and concrete syntax.  Within
   839 the parse tree / AST representations, "constants" are decorated by
   840 their category (class, type, const) and spelled out explicitly with
   841 their full internal name.
   842 
   843 Substantial INCOMPATIBILITY concerning low-level syntax declarations
   844 and translations (translation rules and translation functions in ML).
   845 Some hints on upgrading:
   846 
   847   - Many existing uses of 'syntax' and 'translations' can be replaced
   848     by more modern 'type_notation', 'notation' and 'abbreviation',
   849     which are independent of this issue.
   850 
   851   - 'translations' require markup within the AST; the term syntax
   852     provides the following special forms:
   853 
   854       CONST c   -- produces syntax version of constant c from context
   855       XCONST c  -- literally c, checked as constant from context
   856       c         -- literally c, if declared by 'syntax'
   857 
   858     Plain identifiers are treated as AST variables -- occasionally the
   859     system indicates accidental variables via the error "rhs contains
   860     extra variables".
   861 
   862     Type classes and type constructors are marked according to their
   863     concrete syntax.  Some old translations rules need to be written
   864     for the "type" category, using type constructor application
   865     instead of pseudo-term application of the default category
   866     "logic".
   867 
   868   - 'parse_translation' etc. in ML may use the following
   869     antiquotations:
   870 
   871       @{class_syntax c}   -- type class c within parse tree / AST
   872       @{term_syntax c}    -- type constructor c within parse tree / AST
   873       @{const_syntax c}   -- ML version of "CONST c" above
   874       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
   875 
   876   - Literal types within 'typed_print_translations', i.e. those *not*
   877     represented as pseudo-terms are represented verbatim.  Use @{class
   878     c} or @{type_name c} here instead of the above syntax
   879     antiquotations.
   880 
   881 Note that old non-authentic syntax was based on unqualified base
   882 names, so all of the above "constant" names would coincide.  Recall
   883 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
   884 diagnose syntax problems.
   885 
   886 * Type constructors admit general mixfix syntax, not just infix.
   887 
   888 * Concrete syntax may be attached to local entities without a proof
   889 body, too.  This works via regular mixfix annotations for 'fix',
   890 'def', 'obtain' etc. or via the explicit 'write' command, which is
   891 similar to the 'notation' command in theory specifications.
   892 
   893 * Discontinued unnamed infix syntax (legacy feature for many years) --
   894 need to specify constant name and syntax separately.  Internal ML
   895 datatype constructors have been renamed from InfixName to Infix etc.
   896 Minor INCOMPATIBILITY.
   897 
   898 * Schematic theorem statements need to be explicitly markup as such,
   899 via commands 'schematic_lemma', 'schematic_theorem',
   900 'schematic_corollary'.  Thus the relevance of the proof is made
   901 syntactically clear, which impacts performance in a parallel or
   902 asynchronous interactive environment.  Minor INCOMPATIBILITY.
   903 
   904 * Use of cumulative prems via "!" in some proof methods has been
   905 discontinued (old legacy feature).
   906 
   907 * References 'trace_simp' and 'debug_simp' have been replaced by
   908 configuration options stored in the context. Enabling tracing (the
   909 case of debugging is similar) in proofs works via
   910 
   911   using [[trace_simp = true]]
   912 
   913 Tracing is then active for all invocations of the simplifier in
   914 subsequent goal refinement steps. Tracing may also still be enabled or
   915 disabled via the ProofGeneral settings menu.
   916 
   917 * Separate commands 'hide_class', 'hide_type', 'hide_const',
   918 'hide_fact' replace the former 'hide' KIND command.  Minor
   919 INCOMPATIBILITY.
   920 
   921 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
   922 more efficient than combinations with -q1 or -q2.
   923 
   924 
   925 *** Pure ***
   926 
   927 * Proofterms record type-class reasoning explicitly, using the
   928 "unconstrain" operation internally.  This eliminates all sort
   929 constraints from a theorem and proof, introducing explicit
   930 OFCLASS-premises.  On the proof term level, this operation is
   931 automatically applied at theorem boundaries, such that closed proofs
   932 are always free of sort constraints.  INCOMPATIBILITY for tools that
   933 inspect proof terms.
   934 
   935 * Local theory specifications may depend on extra type variables that
   936 are not present in the result type -- arguments TYPE('a) :: 'a itself
   937 are added internally.  For example:
   938 
   939   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
   940 
   941 * Predicates of locales introduced by classes carry a mandatory
   942 "class" prefix.  INCOMPATIBILITY.
   943 
   944 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
   945 
   946 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
   947 'class' instead.
   948 
   949 * Command 'code_reflect' allows to incorporate generated ML code into
   950 runtime environment; replaces immature code_datatype antiquotation.
   951 INCOMPATIBILITY.
   952 
   953 * Code generator: simple concept for abstract datatypes obeying
   954 invariants.
   955 
   956 * Code generator: details of internal data cache have no impact on the
   957 user space functionality any longer.
   958 
   959 * Methods "unfold_locales" and "intro_locales" ignore non-locale
   960 subgoals.  This is more appropriate for interpretations with 'where'.
   961 INCOMPATIBILITY.
   962 
   963 * Command 'example_proof' opens an empty proof body.  This allows to
   964 experiment with Isar, without producing any persistent result.
   965 
   966 * Commands 'type_notation' and 'no_type_notation' declare type syntax
   967 within a local theory context, with explicit checking of the
   968 constructors involved (in contrast to the raw 'syntax' versions).
   969 
   970 * Commands 'types' and 'typedecl' now work within a local theory
   971 context -- without introducing dependencies on parameters or
   972 assumptions, which is not possible in Isabelle/Pure.
   973 
   974 * Command 'defaultsort' has been renamed to 'default_sort', it works
   975 within a local theory context.  Minor INCOMPATIBILITY.
   976 
   977 
   978 *** HOL ***
   979 
   980 * Command 'typedef' now works within a local theory context -- without
   981 introducing dependencies on parameters or assumptions, which is not
   982 possible in Isabelle/Pure/HOL.  Note that the logical environment may
   983 contain multiple interpretations of local typedefs (with different
   984 non-emptiness proofs), even in a global theory context.
   985 
   986 * New package for quotient types.  Commands 'quotient_type' and
   987 'quotient_definition' may be used for defining types and constants by
   988 quotient constructions.  An example is the type of integers created by
   989 quotienting pairs of natural numbers:
   990 
   991   fun
   992     intrel :: "(nat * nat) => (nat * nat) => bool"
   993   where
   994     "intrel (x, y) (u, v) = (x + v = u + y)"
   995 
   996   quotient_type int = "nat * nat" / intrel
   997     by (auto simp add: equivp_def expand_fun_eq)
   998 
   999   quotient_definition
  1000     "0::int" is "(0::nat, 0::nat)"
  1001 
  1002 The method "lifting" can be used to lift of theorems from the
  1003 underlying "raw" type to the quotient type.  The example
  1004 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  1005 construction and provides a reasoning infrastructure for finite sets.
  1006 
  1007 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  1008 clash with new theory Quotient in Main HOL.
  1009 
  1010 * Moved the SMT binding into the main HOL session, eliminating
  1011 separate HOL-SMT session.
  1012 
  1013 * List membership infix mem operation is only an input abbreviation.
  1014 INCOMPATIBILITY.
  1015 
  1016 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  1017 for future developements; former Library/Word.thy is still present in
  1018 the AFP entry RSAPPS.
  1019 
  1020 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  1021 longer shadowed.  INCOMPATIBILITY.
  1022 
  1023 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  1024 INCOMPATIBILITY.
  1025 
  1026 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  1027 INCOMPATIBILITY.
  1028 
  1029 * Dropped normalizing_semiring etc; use the facts in semiring classes
  1030 instead.  INCOMPATIBILITY.
  1031 
  1032 * Dropped several real-specific versions of lemmas about floor and
  1033 ceiling; use the generic lemmas from theory "Archimedean_Field"
  1034 instead.  INCOMPATIBILITY.
  1035 
  1036   floor_number_of_eq         ~> floor_number_of
  1037   le_floor_eq_number_of      ~> number_of_le_floor
  1038   le_floor_eq_zero           ~> zero_le_floor
  1039   le_floor_eq_one            ~> one_le_floor
  1040   floor_less_eq_number_of    ~> floor_less_number_of
  1041   floor_less_eq_zero         ~> floor_less_zero
  1042   floor_less_eq_one          ~> floor_less_one
  1043   less_floor_eq_number_of    ~> number_of_less_floor
  1044   less_floor_eq_zero         ~> zero_less_floor
  1045   less_floor_eq_one          ~> one_less_floor
  1046   floor_le_eq_number_of      ~> floor_le_number_of
  1047   floor_le_eq_zero           ~> floor_le_zero
  1048   floor_le_eq_one            ~> floor_le_one
  1049   floor_subtract_number_of   ~> floor_diff_number_of
  1050   floor_subtract_one         ~> floor_diff_one
  1051   ceiling_number_of_eq       ~> ceiling_number_of
  1052   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  1053   ceiling_le_zero_eq         ~> ceiling_le_zero
  1054   ceiling_le_eq_one          ~> ceiling_le_one
  1055   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  1056   less_ceiling_eq_zero       ~> zero_less_ceiling
  1057   less_ceiling_eq_one        ~> one_less_ceiling
  1058   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  1059   ceiling_less_eq_zero       ~> ceiling_less_zero
  1060   ceiling_less_eq_one        ~> ceiling_less_one
  1061   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  1062   le_ceiling_eq_zero         ~> zero_le_ceiling
  1063   le_ceiling_eq_one          ~> one_le_ceiling
  1064   ceiling_subtract_number_of ~> ceiling_diff_number_of
  1065   ceiling_subtract_one       ~> ceiling_diff_one
  1066 
  1067 * Theory "Finite_Set": various folding_XXX locales facilitate the
  1068 application of the various fold combinators on finite sets.
  1069 
  1070 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  1071 provides abstract red-black tree type which is backed by "RBT_Impl" as
  1072 implementation.  INCOMPATIBILTY.
  1073 
  1074 * Theory Library/Coinductive_List has been removed -- superseded by
  1075 AFP/thys/Coinductive.
  1076 
  1077 * Theory PReal, including the type "preal" and related operations, has
  1078 been removed.  INCOMPATIBILITY.
  1079 
  1080 * Real: new development using Cauchy Sequences.
  1081 
  1082 * Split off theory "Big_Operators" containing setsum, setprod,
  1083 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  1084 
  1085 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  1086 "Int" etc.  INCOMPATIBILITY.
  1087 
  1088 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  1089 
  1090 * New set of rules "ac_simps" provides combined assoc / commute
  1091 rewrites for all interpretations of the appropriate generic locales.
  1092 
  1093 * Renamed theory "OrderedGroup" to "Groups" and split theory
  1094 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  1095 appropriate and more consistent names suitable for name prefixes
  1096 within the HOL theories.  INCOMPATIBILITY.
  1097 
  1098 * Some generic constants have been put to appropriate theories:
  1099   - less_eq, less: Orderings
  1100   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  1101   - inverse, divide: Rings
  1102 INCOMPATIBILITY.
  1103 
  1104 * More consistent naming of type classes involving orderings (and
  1105 lattices):
  1106 
  1107     lower_semilattice                   ~> semilattice_inf
  1108     upper_semilattice                   ~> semilattice_sup
  1109 
  1110     dense_linear_order                  ~> dense_linorder
  1111 
  1112     pordered_ab_group_add               ~> ordered_ab_group_add
  1113     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  1114     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  1115     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  1116     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  1117     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  1118     pordered_cancel_semiring            ~> ordered_cancel_semiring
  1119     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  1120     pordered_comm_ring                  ~> ordered_comm_ring
  1121     pordered_comm_semiring              ~> ordered_comm_semiring
  1122     pordered_ring                       ~> ordered_ring
  1123     pordered_ring_abs                   ~> ordered_ring_abs
  1124     pordered_semiring                   ~> ordered_semiring
  1125 
  1126     ordered_ab_group_add                ~> linordered_ab_group_add
  1127     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  1128     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  1129     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  1130     ordered_field                       ~> linordered_field
  1131     ordered_field_no_lb                 ~> linordered_field_no_lb
  1132     ordered_field_no_ub                 ~> linordered_field_no_ub
  1133     ordered_field_dense_linear_order    ~> dense_linordered_field
  1134     ordered_idom                        ~> linordered_idom
  1135     ordered_ring                        ~> linordered_ring
  1136     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  1137     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  1138     ordered_ring_strict                 ~> linordered_ring_strict
  1139     ordered_semidom                     ~> linordered_semidom
  1140     ordered_semiring                    ~> linordered_semiring
  1141     ordered_semiring_1                  ~> linordered_semiring_1
  1142     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  1143     ordered_semiring_strict             ~> linordered_semiring_strict
  1144 
  1145   The following slightly odd type classes have been moved to a
  1146   separate theory Library/Lattice_Algebras:
  1147 
  1148     lordered_ab_group_add               ~> lattice_ab_group_add
  1149     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  1150     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  1151     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  1152     lordered_ring                       ~> lattice_ring
  1153 
  1154 INCOMPATIBILITY.
  1155 
  1156 * Refined field classes:
  1157   - classes division_ring_inverse_zero, field_inverse_zero,
  1158     linordered_field_inverse_zero include rule inverse 0 = 0 --
  1159     subsumes former division_by_zero class;
  1160   - numerous lemmas have been ported from field to division_ring.
  1161 INCOMPATIBILITY.
  1162 
  1163 * Refined algebra theorem collections:
  1164   - dropped theorem group group_simps, use algebra_simps instead;
  1165   - dropped theorem group ring_simps, use field_simps instead;
  1166   - proper theorem collection field_simps subsumes former theorem
  1167     groups field_eq_simps and field_simps;
  1168   - dropped lemma eq_minus_self_iff which is a duplicate for
  1169     equal_neg_zero.
  1170 INCOMPATIBILITY.
  1171 
  1172 * Theory Finite_Set and List: some lemmas have been generalized from
  1173 sets to lattices:
  1174 
  1175   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  1176   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  1177   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  1178   union_Union_fold_union        ~> sup_Sup_fold_sup
  1179   Inter_fold_inter              ~> Inf_fold_inf
  1180   Union_fold_union              ~> Sup_fold_sup
  1181   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  1182   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  1183   INTER_fold_inter              ~> INFI_fold_inf
  1184   UNION_fold_union              ~> SUPR_fold_sup
  1185 
  1186 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  1187 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  1188 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  1189 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  1190 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  1191 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  1192 
  1193 * Reorganized theory Multiset: swapped notation of pointwise and
  1194 multiset order:
  1195 
  1196   - pointwise ordering is instance of class order with standard syntax
  1197     <= and <;
  1198   - multiset ordering has syntax <=# and <#; partial order properties
  1199     are provided by means of interpretation with prefix
  1200     multiset_order;
  1201   - less duplication, less historical organization of sections,
  1202     conversion from associations lists to multisets, rudimentary code
  1203     generation;
  1204   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  1205     if needed.
  1206 
  1207 Renamed:
  1208 
  1209   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  1210   multi_count_ext  ~>  multiset_ext
  1211   diff_union_inverse2  ~>  diff_union_cancelR
  1212 
  1213 INCOMPATIBILITY.
  1214 
  1215 * Theory Permutation: replaced local "remove" by List.remove1.
  1216 
  1217 * Code generation: ML and OCaml code is decorated with signatures.
  1218 
  1219 * Theory List: added transpose.
  1220 
  1221 * Library/Nat_Bijection.thy is a collection of bijective functions
  1222 between nat and other types, which supersedes the older libraries
  1223 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  1224 
  1225   Constants:
  1226   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  1227   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  1228   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  1229   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  1230   Countable.pair_encode           ~> prod_encode
  1231   NatIso.prod2nat                 ~> prod_encode
  1232   NatIso.nat2prod                 ~> prod_decode
  1233   NatIso.sum2nat                  ~> sum_encode
  1234   NatIso.nat2sum                  ~> sum_decode
  1235   NatIso.list2nat                 ~> list_encode
  1236   NatIso.nat2list                 ~> list_decode
  1237   NatIso.set2nat                  ~> set_encode
  1238   NatIso.nat2set                  ~> set_decode
  1239 
  1240   Lemmas:
  1241   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  1242   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  1243   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  1244   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  1245   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  1246   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  1247   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  1248   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  1249   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  1250   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  1251   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  1252   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  1253   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  1254 
  1255 * Sledgehammer:
  1256   - Renamed ATP commands:
  1257     atp_info     ~> sledgehammer running_atps
  1258     atp_kill     ~> sledgehammer kill_atps
  1259     atp_messages ~> sledgehammer messages
  1260     atp_minimize ~> sledgehammer minimize
  1261     print_atps   ~> sledgehammer available_atps
  1262     INCOMPATIBILITY.
  1263   - Added user's manual ("isabelle doc sledgehammer").
  1264   - Added option syntax and "sledgehammer_params" to customize
  1265     Sledgehammer's behavior.  See the manual for details.
  1266   - Modified the Isar proof reconstruction code so that it produces
  1267     direct proofs rather than proofs by contradiction.  (This feature
  1268     is still experimental.)
  1269   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  1270     full-typed mode.
  1271   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  1272 
  1273 * Nitpick:
  1274   - Added and implemented "binary_ints" and "bits" options.
  1275   - Added "std" option and implemented support for nonstandard models.
  1276   - Added and implemented "finitize" option to improve the precision
  1277     of infinite datatypes based on a monotonicity analysis.
  1278   - Added support for quotient types.
  1279   - Added support for "specification" and "ax_specification"
  1280     constructs.
  1281   - Added support for local definitions (for "function" and
  1282     "termination" proofs).
  1283   - Added support for term postprocessors.
  1284   - Optimized "Multiset.multiset" and "FinFun.finfun".
  1285   - Improved efficiency of "destroy_constrs" optimization.
  1286   - Fixed soundness bugs related to "destroy_constrs" optimization and
  1287     record getters.
  1288   - Fixed soundness bug related to higher-order constructors.
  1289   - Fixed soundness bug when "full_descrs" is enabled.
  1290   - Improved precision of set constructs.
  1291   - Added "atoms" option.
  1292   - Added cache to speed up repeated Kodkod invocations on the same
  1293     problems.
  1294   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  1295     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  1296     "SAT4J_Light".  INCOMPATIBILITY.
  1297   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  1298     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  1299   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  1300 
  1301 * Method "induct" now takes instantiations of the form t, where t is not
  1302   a variable, as a shorthand for "x == t", where x is a fresh variable.
  1303   If this is not intended, t has to be enclosed in parentheses.
  1304   By default, the equalities generated by definitional instantiations
  1305   are pre-simplified, which may cause parameters of inductive cases
  1306   to disappear, or may even delete some of the inductive cases.
  1307   Use "induct (no_simp)" instead of "induct" to restore the old
  1308   behaviour. The (no_simp) option is also understood by the "cases"
  1309   and "nominal_induct" methods, which now perform pre-simplification, too.
  1310   INCOMPATIBILITY.
  1311 
  1312 
  1313 *** HOLCF ***
  1314 
  1315 * Variable names in lemmas generated by the domain package have
  1316 changed; the naming scheme is now consistent with the HOL datatype
  1317 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  1318 
  1319 * The domain package no longer defines the function "foo_copy" for
  1320 recursive domain "foo".  The reach lemma is now stated directly in
  1321 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  1322 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  1323 
  1324 * Most definedness lemmas generated by the domain package (previously
  1325 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  1326 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  1327 Proofs that used definedness lemmas as intro rules may break,
  1328 potential INCOMPATIBILITY.
  1329 
  1330 * Induction and casedist rules generated by the domain package now
  1331 declare proper case_names (one called "bottom", and one named for each
  1332 constructor).  INCOMPATIBILITY.
  1333 
  1334 * For mutually-recursive domains, separate "reach" and "take_lemma"
  1335 rules are generated for each domain, INCOMPATIBILITY.
  1336 
  1337   foo_bar.reach       ~> foo.reach  bar.reach
  1338   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  1339 
  1340 * Some lemmas generated by the domain package have been renamed for
  1341 consistency with the datatype package, INCOMPATIBILITY.
  1342 
  1343   foo.ind        ~> foo.induct
  1344   foo.finite_ind ~> foo.finite_induct
  1345   foo.coind      ~> foo.coinduct
  1346   foo.casedist   ~> foo.exhaust
  1347   foo.exhaust    ~> foo.nchotomy
  1348 
  1349 * For consistency with other definition packages, the fixrec package
  1350 now generates qualified theorem names, INCOMPATIBILITY.
  1351 
  1352   foo_simps  ~> foo.simps
  1353   foo_unfold ~> foo.unfold
  1354   foo_induct ~> foo.induct
  1355 
  1356 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  1357 method and internal fixrec proofs now use the default simpset instead.
  1358 INCOMPATIBILITY.
  1359 
  1360 * The "contlub" predicate has been removed.  Proof scripts should use
  1361 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  1362 
  1363 * The "admw" predicate has been removed, INCOMPATIBILITY.
  1364 
  1365 * The constants cpair, cfst, and csnd have been removed in favor of
  1366 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  1367 
  1368 
  1369 *** ML ***
  1370 
  1371 * Antiquotations for basic formal entities:
  1372 
  1373     @{class NAME}         -- type class
  1374     @{class_syntax NAME}  -- syntax representation of the above
  1375 
  1376     @{type_name NAME}     -- logical type
  1377     @{type_abbrev NAME}   -- type abbreviation
  1378     @{nonterminal NAME}   -- type of concrete syntactic category
  1379     @{type_syntax NAME}   -- syntax representation of any of the above
  1380 
  1381     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  1382     @{const_abbrev NAME}  -- abbreviated constant
  1383     @{const_syntax NAME}  -- syntax representation of any of the above
  1384 
  1385 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  1386 syntax constant (cf. 'syntax' command).
  1387 
  1388 * Antiquotation @{make_string} inlines a function to print arbitrary
  1389 values similar to the ML toplevel.  The result is compiler dependent
  1390 and may fall back on "?" in certain situations.
  1391 
  1392 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  1393 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  1394 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  1395 not work with the asynchronous Isar document model.
  1396 
  1397 * Configuration options now admit dynamic default values, depending on
  1398 the context or even global references.
  1399 
  1400 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  1401 uses an efficient external library if available (for Poly/ML).
  1402 
  1403 * Renamed some important ML structures, while keeping the old names
  1404 for some time as aliases within the structure Legacy:
  1405 
  1406   OuterKeyword  ~>  Keyword
  1407   OuterLex      ~>  Token
  1408   OuterParse    ~>  Parse
  1409   OuterSyntax   ~>  Outer_Syntax
  1410   PrintMode     ~>  Print_Mode
  1411   SpecParse     ~>  Parse_Spec
  1412   ThyInfo       ~>  Thy_Info
  1413   ThyLoad       ~>  Thy_Load
  1414   ThyOutput     ~>  Thy_Output
  1415   TypeInfer     ~>  Type_Infer
  1416 
  1417 Note that "open Legacy" simplifies porting of sources, but forgetting
  1418 to remove it again will complicate porting again in the future.
  1419 
  1420 * Most operations that refer to a global context are named
  1421 accordingly, e.g. Simplifier.global_context or
  1422 ProofContext.init_global.  There are some situations where a global
  1423 context actually works, but under normal circumstances one needs to
  1424 pass the proper local context through the code!
  1425 
  1426 * Discontinued old TheoryDataFun with its copy/init operation -- data
  1427 needs to be pure.  Functor Theory_Data_PP retains the traditional
  1428 Pretty.pp argument to merge, which is absent in the standard
  1429 Theory_Data version.
  1430 
  1431 * Sorts.certify_sort and derived "cert" operations for types and terms
  1432 no longer minimize sorts.  Thus certification at the boundary of the
  1433 inference kernel becomes invariant under addition of class relations,
  1434 which is an important monotonicity principle.  Sorts are now minimized
  1435 in the syntax layer only, at the boundary between the end-user and the
  1436 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  1437 explicitly in rare situations.
  1438 
  1439 * Renamed old-style Drule.standard to Drule.export_without_context, to
  1440 emphasize that this is in no way a standard operation.
  1441 INCOMPATIBILITY.
  1442 
  1443 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  1444 usual for resolution.  Rare INCOMPATIBILITY.
  1445 
  1446 * Renamed varify/unvarify operations to varify_global/unvarify_global
  1447 to emphasize that these only work in a global situation (which is
  1448 quite rare).
  1449 
  1450 * Curried take and drop in library.ML; negative length is interpreted
  1451 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  1452 
  1453 * Proof terms: type substitutions on proof constants now use canonical
  1454 order of type variables.  INCOMPATIBILITY for tools working with proof
  1455 terms.
  1456 
  1457 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  1458 may no longer carry premises.  User-level specifications are
  1459 transformed accordingly by Thm.add_axiom/add_def.
  1460 
  1461 
  1462 *** System ***
  1463 
  1464 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  1465 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  1466 proof terms are enabled unconditionally in the new HOL-Proofs image.
  1467 
  1468 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  1469 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  1470 respectively.
  1471 
  1472 * Old lib/scripts/polyml-platform is superseded by the
  1473 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  1474 variant, even on a 64 bit machine.  The following example setting
  1475 prefers 64 bit if available:
  1476 
  1477   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  1478 
  1479 * The preliminary Isabelle/jEdit application demonstrates the emerging
  1480 Isabelle/Scala layer for advanced prover interaction and integration.
  1481 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  1482 component.
  1483 
  1484 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  1485 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  1486 similar to the default assignment of the document preparation system
  1487 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  1488 provides some operations for direct access to the font without asking
  1489 the user for manual installation.
  1490 
  1491 
  1492 
  1493 New in Isabelle2009-1 (December 2009)
  1494 -------------------------------------
  1495 
  1496 *** General ***
  1497 
  1498 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  1499 one backslash should be used, even in ML sources.
  1500 
  1501 
  1502 *** Pure ***
  1503 
  1504 * Locale interpretation propagates mixins along the locale hierarchy.
  1505 The currently only available mixins are the equations used to map
  1506 local definitions to terms of the target domain of an interpretation.
  1507 
  1508 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  1509 loc" to print all interpretations of locale "loc" in the theory.
  1510 Interpretations in proofs are not shown.
  1511 
  1512 * Thoroughly revised locales tutorial.  New section on conditional
  1513 interpretation.
  1514 
  1515 * On instantiation of classes, remaining undefined class parameters
  1516 are formally declared.  INCOMPATIBILITY.
  1517 
  1518 
  1519 *** Document preparation ***
  1520 
  1521 * New generalized style concept for printing terms: @{foo (style) ...}
  1522 instead of @{foo_style style ...}  (old form is still retained for
  1523 backward compatibility).  Styles can be also applied for
  1524 antiquotations prop, term_type and typeof.
  1525 
  1526 
  1527 *** HOL ***
  1528 
  1529 * New proof method "smt" for a combination of first-order logic with
  1530 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  1531 fixed-size bitvectors; there is also basic support for higher-order
  1532 features (esp. lambda abstractions).  It is an incomplete decision
  1533 procedure based on external SMT solvers using the oracle mechanism;
  1534 for the SMT solver Z3, this method is proof-producing.  Certificates
  1535 are provided to avoid calling the external solvers solely for
  1536 re-checking proofs.  Due to a remote SMT service there is no need for
  1537 installing SMT solvers locally.  See src/HOL/SMT.
  1538 
  1539 * New commands to load and prove verification conditions generated by
  1540 the Boogie program verifier or derived systems (e.g. the Verifying C
  1541 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1542 
  1543 * New counterexample generator tool 'nitpick' based on the Kodkod
  1544 relational model finder.  See src/HOL/Tools/Nitpick and
  1545 src/HOL/Nitpick_Examples.
  1546 
  1547 * New commands 'code_pred' and 'values' to invoke the predicate
  1548 compiler and to enumerate values of inductive predicates.
  1549 
  1550 * A tabled implementation of the reflexive transitive closure.
  1551 
  1552 * New implementation of quickcheck uses generic code generator;
  1553 default generators are provided for all suitable HOL types, records
  1554 and datatypes.  Old quickcheck can be re-activated importing theory
  1555 Library/SML_Quickcheck.
  1556 
  1557 * New testing tool Mirabelle for automated proof tools.  Applies
  1558 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1559 every proof step in a theory.  To be used in batch mode via the
  1560 "mirabelle" utility.
  1561 
  1562 * New proof method "sos" (sum of squares) for nonlinear real
  1563 arithmetic (originally due to John Harison). It requires theory
  1564 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1565 works well in practice on quantifier-free real arithmetic with +, -,
  1566 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1567 inequalities between polynomials.  It makes use of external
  1568 semidefinite programming solvers.  Method "sos" generates a
  1569 certificate that can be pasted into the proof thus avoiding the need
  1570 to call an external tool every time the proof is checked.  See
  1571 src/HOL/Library/Sum_Of_Squares.
  1572 
  1573 * New method "linarith" invokes existing linear arithmetic decision
  1574 procedure only.
  1575 
  1576 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1577 
  1578 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1579 Causes full type information to be output to the ATPs.  This slows
  1580 ATPs down considerably but eliminates a source of unsound "proofs"
  1581 that fail later.
  1582 
  1583 * New method "metisFT": A version of metis that uses full type
  1584 information in order to avoid failures of proof reconstruction.
  1585 
  1586 * New evaluator "approximate" approximates an real valued term using
  1587 the same method as the approximation method.
  1588 
  1589 * Method "approximate" now supports arithmetic expressions as
  1590 boundaries of intervals and implements interval splitting and Taylor
  1591 series expansion.
  1592 
  1593 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1594 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1595 
  1596 * New theory SupInf of the supremum and infimum operators for sets of
  1597 reals.
  1598 
  1599 * New theory Probability, which contains a development of measure
  1600 theory, eventually leading to Lebesgue integration and probability.
  1601 
  1602 * Extended Multivariate Analysis to include derivation and Brouwer's
  1603 fixpoint theorem.
  1604 
  1605 * Reorganization of number theory, INCOMPATIBILITY:
  1606   - new number theory development for nat and int, in theories Divides
  1607     and GCD as well as in new session Number_Theory
  1608   - some constants and facts now suffixed with _nat and _int
  1609     accordingly
  1610   - former session NumberTheory now named Old_Number_Theory, including
  1611     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1612   - moved theory Pocklington from src/HOL/Library to
  1613     src/HOL/Old_Number_Theory
  1614 
  1615 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1616 lcm of finite and infinite sets. It is shown that they form a complete
  1617 lattice.
  1618 
  1619 * Class semiring_div requires superclass no_zero_divisors and proof of
  1620 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1621 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1622 generalized to class semiring_div, subsuming former theorems
  1623 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1624 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1625 INCOMPATIBILITY.
  1626 
  1627 * Refinements to lattice classes and sets:
  1628   - less default intro/elim rules in locale variant, more default
  1629     intro/elim rules in class variant: more uniformity
  1630   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1631     le_inf_iff
  1632   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1633     sup_aci)
  1634   - renamed ACI to inf_sup_aci
  1635   - new class "boolean_algebra"
  1636   - class "complete_lattice" moved to separate theory
  1637     "Complete_Lattice"; corresponding constants (and abbreviations)
  1638     renamed and with authentic syntax:
  1639     Set.Inf ~>    Complete_Lattice.Inf
  1640     Set.Sup ~>    Complete_Lattice.Sup
  1641     Set.INFI ~>   Complete_Lattice.INFI
  1642     Set.SUPR ~>   Complete_Lattice.SUPR
  1643     Set.Inter ~>  Complete_Lattice.Inter
  1644     Set.Union ~>  Complete_Lattice.Union
  1645     Set.INTER ~>  Complete_Lattice.INTER
  1646     Set.UNION ~>  Complete_Lattice.UNION
  1647   - authentic syntax for
  1648     Set.Pow
  1649     Set.image
  1650   - mere abbreviations:
  1651     Set.empty               (for bot)
  1652     Set.UNIV                (for top)
  1653     Set.inter               (for inf, formerly Set.Int)
  1654     Set.union               (for sup, formerly Set.Un)
  1655     Complete_Lattice.Inter  (for Inf)
  1656     Complete_Lattice.Union  (for Sup)
  1657     Complete_Lattice.INTER  (for INFI)
  1658     Complete_Lattice.UNION  (for SUPR)
  1659   - object-logic definitions as far as appropriate
  1660 
  1661 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1662 Un_subset_iff are explicitly deleted as default simp rules; then also
  1663 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1664 deleted to achieve the desired effect.
  1665 
  1666 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1667 rules by default any longer; the same applies to min_max.inf_absorb1
  1668 etc.  INCOMPATIBILITY.
  1669 
  1670 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1671 pred_set_conv by default.  INCOMPATIBILITY.
  1672 
  1673 * Power operations on relations and functions are now one dedicated
  1674 constant "compow" with infix syntax "^^".  Power operation on
  1675 multiplicative monoids retains syntax "^" and is now defined generic
  1676 in class power.  INCOMPATIBILITY.
  1677 
  1678 * Relation composition "R O S" now has a more standard argument order:
  1679 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  1680 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  1681 break, since the O_assoc rule was not rewritten like this.  Fix using
  1682 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  1683 
  1684 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  1685 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  1686 INCOMPATIBILITY.
  1687 
  1688 * Most rules produced by inductive and datatype package have mandatory
  1689 prefixes.  INCOMPATIBILITY.
  1690 
  1691 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  1692 the attribute of the same name.  Each of the theorems in the list
  1693 DERIV_intros assumes composition with an additional function and
  1694 matches a variable to the derivative, which has to be solved by the
  1695 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  1696 of most elementary terms.  Former Maclauren.DERIV_tac and
  1697 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  1698 INCOMPATIBILITY.
  1699 
  1700 * Code generator attributes follow the usual underscore convention:
  1701     code_unfold     replaces    code unfold
  1702     code_post       replaces    code post
  1703     etc.
  1704   INCOMPATIBILITY.
  1705 
  1706 * Renamed methods:
  1707     sizechange -> size_change
  1708     induct_scheme -> induction_schema
  1709   INCOMPATIBILITY.
  1710 
  1711 * Discontinued abbreviation "arbitrary" of constant "undefined".
  1712 INCOMPATIBILITY, use "undefined" directly.
  1713 
  1714 * Renamed theorems:
  1715     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  1716     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  1717     Suc_plus1 -> Suc_eq_plus1
  1718     *anti_sym -> *antisym*
  1719     vector_less_eq_def -> vector_le_def
  1720   INCOMPATIBILITY.
  1721 
  1722 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  1723 INCOMPATIBILITY.
  1724 
  1725 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  1726 INCOMPATIBILITY.
  1727 
  1728 
  1729 *** HOLCF ***
  1730 
  1731 * Theory Representable defines a class "rep" of domains that are
  1732 representable (via an ep-pair) in the universal domain type "udom".
  1733 Instances are provided for all type constructors defined in HOLCF.
  1734 
  1735 * The 'new_domain' command is a purely definitional version of the
  1736 domain package, for representable domains.  Syntax is identical to the
  1737 old domain package.  The 'new_domain' package also supports indirect
  1738 recursion using previously-defined type constructors.  See
  1739 src/HOLCF/ex/New_Domain.thy for examples.
  1740 
  1741 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  1742 on the left-hand side of an equation, and then performs
  1743 simplification.  Rewriting is done using rules declared with the
  1744 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  1745 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  1746 
  1747 * The pattern-match compiler in 'fixrec' can now handle constructors
  1748 with HOL function types.  Pattern-match combinators for the Pair
  1749 constructor are pre-configured.
  1750 
  1751 * The 'fixrec' package now produces better fixed-point induction rules
  1752 for mutually-recursive definitions:  Induction rules have conclusions
  1753 of the form "P foo bar" instead of "P <foo, bar>".
  1754 
  1755 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  1756 been renamed to "below".  The name "below" now replaces "less" in many
  1757 theorem names.  (Legacy theorem names using "less" are still supported
  1758 as well.)
  1759 
  1760 * The 'fixrec' package now supports "bottom patterns".  Bottom
  1761 patterns can be used to generate strictness rules, or to make
  1762 functions more strict (much like the bang-patterns supported by the
  1763 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  1764 examples.
  1765 
  1766 
  1767 *** ML ***
  1768 
  1769 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  1770 errors and run-time exceptions, including detailed source positions.
  1771 
  1772 * Structure Name_Space (formerly NameSpace) now manages uniquely
  1773 identified entries, with some additional information such as source
  1774 position, logical grouping etc.
  1775 
  1776 * Theory and context data is now introduced by the simplified and
  1777 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  1778 to be pure, but the old TheoryDataFun for mutable data (with explicit
  1779 copy operation) is still available for some time.
  1780 
  1781 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  1782 provides a high-level programming interface to synchronized state
  1783 variables with atomic update.  This works via pure function
  1784 application within a critical section -- its runtime should be as
  1785 short as possible; beware of deadlocks if critical code is nested,
  1786 either directly or indirectly via other synchronized variables!
  1787 
  1788 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  1789 wraps raw ML references, explicitly indicating their non-thread-safe
  1790 behaviour.  The Isar toplevel keeps this structure open, to
  1791 accommodate Proof General as well as quick and dirty interactive
  1792 experiments with references.
  1793 
  1794 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  1795 parallel tactical reasoning.
  1796 
  1797 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  1798 are similar to SUBPROOF, but are slightly more flexible: only the
  1799 specified parts of the subgoal are imported into the context, and the
  1800 body tactic may introduce new subgoals and schematic variables.
  1801 
  1802 * Old tactical METAHYPS, which does not observe the proof context, has
  1803 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  1804 or Subgoal.FOCUS etc.
  1805 
  1806 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  1807 functors have their own ML name space there is no point to mark them
  1808 separately.)  Minor INCOMPATIBILITY.
  1809 
  1810 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  1811 
  1812 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  1813 INCOMPATIBILITY.
  1814 
  1815 * Operations of structure Skip_Proof no longer require quick_and_dirty
  1816 mode, which avoids critical setmp.
  1817 
  1818 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  1819 combinators for "args".  INCOMPATIBILITY, need to use simplified
  1820 Attrib/Method.setup introduced in Isabelle2009.
  1821 
  1822 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  1823 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  1824 last resort.  INCOMPATIBILITY.
  1825 
  1826 * Display.pretty_thm now requires a proper context (cf. former
  1827 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  1828 or even Display.pretty_thm_without_context as last resort.
  1829 INCOMPATIBILITY.
  1830 
  1831 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  1832 Syntax.pretty_typ/term directly, preferably with proper context
  1833 instead of global theory.
  1834 
  1835 
  1836 *** System ***
  1837 
  1838 * Further fine tuning of parallel proof checking, scales up to 8 cores
  1839 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  1840 usedir option -q.
  1841 
  1842 * Support for additional "Isabelle components" via etc/components, see
  1843 also the system manual.
  1844 
  1845 * The isabelle makeall tool now operates on all components with
  1846 IsaMakefile, not just hardwired "logics".
  1847 
  1848 * Removed "compress" option from isabelle-process and isabelle usedir;
  1849 this is always enabled.
  1850 
  1851 * Discontinued support for Poly/ML 4.x versions.
  1852 
  1853 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  1854 on a given logic image.  This requires the lighttpd webserver and is
  1855 currently supported on Linux only.
  1856 
  1857 
  1858 
  1859 New in Isabelle2009 (April 2009)
  1860 --------------------------------
  1861 
  1862 *** General ***
  1863 
  1864 * Simplified main Isabelle executables, with less surprises on
  1865 case-insensitive file-systems (such as Mac OS).
  1866 
  1867   - The main Isabelle tool wrapper is now called "isabelle" instead of
  1868     "isatool."
  1869 
  1870   - The former "isabelle" alias for "isabelle-process" has been
  1871     removed (should rarely occur to regular users).
  1872 
  1873   - The former "isabelle-interface" and its alias "Isabelle" have been
  1874     removed (interfaces are now regular Isabelle tools).
  1875 
  1876 Within scripts and make files, the Isabelle environment variables
  1877 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  1878 respectively.  (The latter are still available as legacy feature.)
  1879 
  1880 The old isabelle-interface wrapper could react in confusing ways if
  1881 the interface was uninstalled or changed otherwise.  Individual
  1882 interface tool configuration is now more explicit, see also the
  1883 Isabelle system manual.  In particular, Proof General is now available
  1884 via "isabelle emacs".
  1885 
  1886 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  1887 purge installed copies of Isabelle executables and re-run "isabelle
  1888 install -p ...", or use symlinks.
  1889 
  1890 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  1891 old ~/isabelle, which was slightly non-standard and apt to cause
  1892 surprises on case-insensitive file-systems (such as Mac OS).
  1893 
  1894 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  1895 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  1896 care is required when using older releases of Isabelle.  Note that
  1897 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  1898 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  1899 
  1900 * Proofs of fully specified statements are run in parallel on
  1901 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  1902 a regular 4-core machine, if the initial heap space is made reasonably
  1903 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  1904 
  1905 * The main reference manuals ("isar-ref", "implementation", and
  1906 "system") have been updated and extended.  Formally checked references
  1907 as hyperlinks are now available uniformly.
  1908 
  1909 
  1910 *** Pure ***
  1911 
  1912 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  1913 respects.  The most important changes are listed below.  See the
  1914 Tutorial on Locales ("locales" manual) for details.
  1915 
  1916 - In locale expressions, instantiation replaces renaming.  Parameters
  1917 must be declared in a for clause.  To aid compatibility with previous
  1918 parameter inheritance, in locale declarations, parameters that are not
  1919 'touched' (instantiation position "_" or omitted) are implicitly added
  1920 with their syntax at the beginning of the for clause.
  1921 
  1922 - Syntax from abbreviations and definitions in locales is available in
  1923 locale expressions and context elements.  The latter is particularly
  1924 useful in locale declarations.
  1925 
  1926 - More flexible mechanisms to qualify names generated by locale
  1927 expressions.  Qualifiers (prefixes) may be specified in locale
  1928 expressions, and can be marked as mandatory (syntax: "name!:") or
  1929 optional (syntax "name?:").  The default depends for plain "name:"
  1930 depends on the situation where a locale expression is used: in
  1931 commands 'locale' and 'sublocale' prefixes are optional, in
  1932 'interpretation' and 'interpret' prefixes are mandatory.  The old
  1933 implicit qualifiers derived from the parameter names of a locale are
  1934 no longer generated.
  1935 
  1936 - Command "sublocale l < e" replaces "interpretation l < e".  The
  1937 instantiation clause in "interpretation" and "interpret" (square
  1938 brackets) is no longer available.  Use locale expressions.
  1939 
  1940 - When converting proof scripts, mandatory qualifiers in
  1941 'interpretation' and 'interpret' should be retained by default, even
  1942 if this is an INCOMPATIBILITY compared to former behavior.  In the
  1943 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  1944 in locale expressions range over a single locale instance only.
  1945 
  1946 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  1947 In existing theorem specifications replace the includes element by the
  1948 respective context elements of the included locale, omitting those
  1949 that are already present in the theorem specification.  Multiple
  1950 assume elements of a locale should be replaced by a single one
  1951 involving the locale predicate.  In the proof body, declarations (most
  1952 notably theorems) may be regained by interpreting the respective
  1953 locales in the proof context as required (command "interpret").
  1954 
  1955 If using "includes" in replacement of a target solely because the
  1956 parameter types in the theorem are not as general as in the target,
  1957 consider declaring a new locale with additional type constraints on
  1958 the parameters (context element "constrains").
  1959 
  1960 - Discontinued "locale (open)".  INCOMPATIBILITY.
  1961 
  1962 - Locale interpretation commands no longer attempt to simplify goal.
  1963 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  1964 methods intro_locales and unfold_locales to clarify.
  1965 
  1966 - Locale interpretation commands no longer accept interpretation
  1967 attributes.  INCOMPATIBILITY.
  1968 
  1969 * Class declaration: so-called "base sort" must not be given in import
  1970 list any longer, but is inferred from the specification.  Particularly
  1971 in HOL, write
  1972 
  1973     class foo = ...
  1974 
  1975 instead of
  1976 
  1977     class foo = type + ...
  1978 
  1979 * Class target: global versions of theorems stemming do not carry a
  1980 parameter prefix any longer.  INCOMPATIBILITY.
  1981 
  1982 * Class 'instance' command no longer accepts attached definitions.
  1983 INCOMPATIBILITY, use proper 'instantiation' target instead.
  1984 
  1985 * Recovered hiding of consts, which was accidentally broken in
  1986 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  1987 makes c inaccessible; consider using ``hide (open) const c'' instead.
  1988 
  1989 * Slightly more coherent Pure syntax, with updated documentation in
  1990 isar-ref manual.  Removed locales meta_term_syntax and
  1991 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  1992 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  1993 directly in regular applications.
  1994 
  1995 * There is a new syntactic category "float_const" for signed decimal
  1996 fractions (e.g. 123.45 or -123.45).
  1997 
  1998 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  1999 interface with 'setup' command instead.
  2000 
  2001 * Command 'local_setup' is similar to 'setup', but operates on a local
  2002 theory context.
  2003 
  2004 * The 'axiomatization' command now only works within a global theory
  2005 context.  INCOMPATIBILITY.
  2006 
  2007 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  2008 hypotheses.  Sorts required in the course of reasoning need to be
  2009 covered by the constraints in the initial statement, completed by the
  2010 type instance information of the background theory.  Non-trivial sort
  2011 hypotheses, which rarely occur in practice, may be specified via
  2012 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  2013 
  2014   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  2015 
  2016 The result contains an implicit sort hypotheses as before --
  2017 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  2018 normalization.
  2019 
  2020 * Generalized Isar history, with support for linear undo, direct state
  2021 addressing etc.
  2022 
  2023 * Changed defaults for unify configuration options:
  2024 
  2025   unify_trace_bound = 50 (formerly 25)
  2026   unify_search_bound = 60 (formerly 30)
  2027 
  2028 * Different bookkeeping for code equations (INCOMPATIBILITY):
  2029 
  2030   a) On theory merge, the last set of code equations for a particular
  2031      constant is taken (in accordance with the policy applied by other
  2032      parts of the code generator framework).
  2033 
  2034   b) Code equations stemming from explicit declarations (e.g. code
  2035      attribute) gain priority over default code equations stemming
  2036      from definition, primrec, fun etc.
  2037 
  2038 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  2039 
  2040 * Unified theorem tables for both code generators.  Thus [code
  2041 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  2042 
  2043 * Command 'find_consts' searches for constants based on type and name
  2044 patterns, e.g.
  2045 
  2046     find_consts "_ => bool"
  2047 
  2048 By default, matching is against subtypes, but it may be restricted to
  2049 the whole type.  Searching by name is possible.  Multiple queries are
  2050 conjunctive and queries may be negated by prefixing them with a
  2051 hyphen:
  2052 
  2053     find_consts strict: "_ => bool" name: "Int" -"int => int"
  2054 
  2055 * New 'find_theorems' criterion "solves" matches theorems that
  2056 directly solve the current goal (modulo higher-order unification).
  2057 
  2058 * Auto solve feature for main theorem statements: whenever a new goal
  2059 is stated, "find_theorems solves" is called; any theorems that could
  2060 solve the lemma directly are listed as part of the goal state.
  2061 Cf. associated options in Proof General Isabelle settings menu,
  2062 enabled by default, with reasonable timeout for pathological cases of
  2063 higher-order unification.
  2064 
  2065 
  2066 *** Document preparation ***
  2067 
  2068 * Antiquotation @{lemma} now imitates a regular terminal proof,
  2069 demanding keyword 'by' and supporting the full method expression
  2070 syntax just like the Isar command 'by'.
  2071 
  2072 
  2073 *** HOL ***
  2074 
  2075 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  2076 points Main and Complex_Main remain as before.
  2077 
  2078 * Logic image HOL-Plain provides a minimal HOL with the most important
  2079 tools available (inductive, datatype, primrec, ...).  This facilitates
  2080 experimentation and tool development.  Note that user applications
  2081 (and library theories) should never refer to anything below theory
  2082 Main, as before.
  2083 
  2084 * Logic image HOL-Main stops at theory Main, and thus facilitates
  2085 experimentation due to shorter build times.
  2086 
  2087 * Logic image HOL-NSA contains theories of nonstandard analysis which
  2088 were previously part of former HOL-Complex.  Entry point Hyperreal
  2089 remains valid, but theories formerly using Complex_Main should now use
  2090 new entry point Hypercomplex.
  2091 
  2092 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  2093 Posix processes.  Avoids potentially expensive forking of the ML
  2094 process.  New thread-based implementation also works on non-Unix
  2095 platforms (Cygwin).  Provers are no longer hardwired, but defined
  2096 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  2097 commands are covered in the isar-ref manual.
  2098 
  2099 * Wrapper scripts for remote SystemOnTPTP service allows to use
  2100 sledgehammer without local ATP installation (Vampire etc.). Other
  2101 provers may be included via suitable ML wrappers, see also
  2102 src/HOL/ATP_Linkup.thy.
  2103 
  2104 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  2105 menu.
  2106 
  2107 * The metis method no longer fails because the theorem is too trivial
  2108 (contains the empty clause).
  2109 
  2110 * The metis method now fails in the usual manner, rather than raising
  2111 an exception, if it determines that it cannot prove the theorem.
  2112 
  2113 * Method "coherent" implements a prover for coherent logic (see also
  2114 src/Tools/coherent.ML).
  2115 
  2116 * Constants "undefined" and "default" replace "arbitrary".  Usually
  2117 "undefined" is the right choice to replace "arbitrary", though
  2118 logically there is no difference.  INCOMPATIBILITY.
  2119 
  2120 * Command "value" now integrates different evaluation mechanisms.  The
  2121 result of the first successful evaluation mechanism is printed.  In
  2122 square brackets a particular named evaluation mechanisms may be
  2123 specified (currently, [SML], [code] or [nbe]).  See further
  2124 src/HOL/ex/Eval_Examples.thy.
  2125 
  2126 * Normalization by evaluation now allows non-leftlinear equations.
  2127 Declare with attribute [code nbe].
  2128 
  2129 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  2130 as the structured Isar versions "cases" and "induct", cf. the
  2131 corresponding "cases" and "induct" attributes.  Mutual induction rules
  2132 are now presented as a list of individual projections
  2133 (e.g. foo_bar.inducts for types foo and bar); the old format with
  2134 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  2135 rare situations a different rule is selected --- notably nested tuple
  2136 elimination instead of former prod.exhaust: use explicit (case_tac t
  2137 rule: prod.exhaust) here.
  2138 
  2139 * Attributes "cases", "induct", "coinduct" support "del" option.
  2140 
  2141 * Removed fact "case_split_thm", which duplicates "case_split".
  2142 
  2143 * The option datatype has been moved to a new theory Option.  Renamed
  2144 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  2145 
  2146 * New predicate "strict_mono" classifies strict functions on partial
  2147 orders.  With strict functions on linear orders, reasoning about
  2148 (in)equalities is facilitated by theorems "strict_mono_eq",
  2149 "strict_mono_less_eq" and "strict_mono_less".
  2150 
  2151 * Some set operations are now proper qualified constants with
  2152 authentic syntax.  INCOMPATIBILITY:
  2153 
  2154     op Int ~>   Set.Int
  2155     op Un ~>    Set.Un
  2156     INTER ~>    Set.INTER
  2157     UNION ~>    Set.UNION
  2158     Inter ~>    Set.Inter
  2159     Union ~>    Set.Union
  2160     {} ~>       Set.empty
  2161     UNIV ~>     Set.UNIV
  2162 
  2163 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  2164 theory Set.
  2165 
  2166 * Auxiliary class "itself" has disappeared -- classes without any
  2167 parameter are treated as expected by the 'class' command.
  2168 
  2169 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  2170 
  2171 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  2172 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  2173 
  2174 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  2175 method "approximation".  It proves formulas on real values by using
  2176 interval arithmetic.  In the formulas are also the transcendental
  2177 functions sin, cos, tan, atan, ln, exp and the constant pi are
  2178 allowed. For examples see
  2179 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  2180 
  2181 * Theory "Reflection" now resides in HOL/Library.
  2182 
  2183 * Entry point to Word library now simply named "Word".
  2184 INCOMPATIBILITY.
  2185 
  2186 * Made source layout more coherent with logical distribution
  2187 structure:
  2188 
  2189     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  2190     src/HOL/Library/Code_Message.thy ~> src/HOL/
  2191     src/HOL/Library/GCD.thy ~> src/HOL/
  2192     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  2193     src/HOL/Library/Parity.thy ~> src/HOL/
  2194     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  2195     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  2196     src/HOL/Real/Lubs.thy ~> src/HOL/
  2197     src/HOL/Real/PReal.thy ~> src/HOL/
  2198     src/HOL/Real/Rational.thy ~> src/HOL/
  2199     src/HOL/Real/RComplete.thy ~> src/HOL/
  2200     src/HOL/Real/RealDef.thy ~> src/HOL/
  2201     src/HOL/Real/RealPow.thy ~> src/HOL/
  2202     src/HOL/Real/Real.thy ~> src/HOL/
  2203     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  2204     src/HOL/Complex/Complex.thy ~> src/HOL/
  2205     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  2206     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  2207     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  2208     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  2209     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  2210     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  2211     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  2212     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  2213     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  2214     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  2215     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  2216     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  2217     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  2218     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  2219     src/HOL/Real/Float ~> src/HOL/Library/
  2220     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  2221     src/HOL/Real/RealVector.thy ~> src/HOL/
  2222 
  2223     src/HOL/arith_data.ML ~> src/HOL/Tools
  2224     src/HOL/hologic.ML ~> src/HOL/Tools
  2225     src/HOL/simpdata.ML ~> src/HOL/Tools
  2226     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  2227     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  2228     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  2229     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  2230     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  2231     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  2232     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  2233 
  2234     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  2235     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  2236     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  2237     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  2238     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  2239     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  2240 
  2241 * If methods "eval" and "evaluation" encounter a structured proof
  2242 state with !!/==>, only the conclusion is evaluated to True (if
  2243 possible), avoiding strange error messages.
  2244 
  2245 * Method "sizechange" automates termination proofs using (a
  2246 modification of) the size-change principle.  Requires SAT solver.  See
  2247 src/HOL/ex/Termination.thy for examples.
  2248 
  2249 * Simplifier: simproc for let expressions now unfolds if bound
  2250 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  2251 
  2252 * Method "arith": Linear arithmetic now ignores all inequalities when
  2253 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  2254 
  2255 * New attribute "arith" for facts that should always be used
  2256 automatically by arithmetic. It is intended to be used locally in
  2257 proofs, e.g.
  2258 
  2259   assumes [arith]: "x > 0"
  2260 
  2261 Global usage is discouraged because of possible performance impact.
  2262 
  2263 * New classes "top" and "bot" with corresponding operations "top" and
  2264 "bot" in theory Orderings; instantiation of class "complete_lattice"
  2265 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  2266 
  2267 * Changed definition lemma "less_fun_def" in order to provide an
  2268 instance for preorders on functions; use lemma "less_le" instead.
  2269 INCOMPATIBILITY.
  2270 
  2271 * Theory Orderings: class "wellorder" moved here, with explicit
  2272 induction rule "less_induct" as assumption.  For instantiation of
  2273 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  2274 INCOMPATIBILITY.
  2275 
  2276 * Theory Orderings: added class "preorder" as superclass of "order".
  2277 INCOMPATIBILITY: Instantiation proofs for order, linorder
  2278 etc. slightly changed.  Some theorems named order_class.* now named
  2279 preorder_class.*.
  2280 
  2281 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  2282 "diag" to "Id_on".
  2283 
  2284 * Theory Finite_Set: added a new fold combinator of type
  2285 
  2286   ('a => 'b => 'b) => 'b => 'a set => 'b
  2287 
  2288 Occasionally this is more convenient than the old fold combinator
  2289 which is now defined in terms of the new one and renamed to
  2290 fold_image.
  2291 
  2292 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  2293 and "ring_simps" have been replaced by "algebra_simps" (which can be
  2294 extended with further lemmas!).  At the moment both still exist but
  2295 the former will disappear at some point.
  2296 
  2297 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  2298 class recpower.  Type-specific simp rules for various recpower types
  2299 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  2300 
  2301 rat_power_0    -> power_0
  2302 rat_power_Suc  -> power_Suc
  2303 realpow_0      -> power_0
  2304 realpow_Suc    -> power_Suc
  2305 complexpow_0   -> power_0
  2306 complexpow_Suc -> power_Suc
  2307 power_poly_0   -> power_0
  2308 power_poly_Suc -> power_Suc
  2309 
  2310 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  2311 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  2312 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  2313 of lemmas from Divides has been generalized from nat to class
  2314 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  2315 renames resulting from duplicate elimination:
  2316 
  2317     dvd_def_mod ~>          dvd_eq_mod_eq_0
  2318     zero_dvd_iff ~>         dvd_0_left_iff
  2319     dvd_0 ~>                dvd_0_right
  2320     DIVISION_BY_ZERO_DIV ~> div_by_0
  2321     DIVISION_BY_ZERO_MOD ~> mod_by_0
  2322     mult_div ~>             div_mult_self2_is_id
  2323     mult_mod ~>             mod_mult_self2_is_0
  2324 
  2325 * Theory IntDiv: removed many lemmas that are instances of class-based
  2326 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  2327 rename old lemmas as follows:
  2328 
  2329 dvd_diff               -> nat_dvd_diff
  2330 dvd_zminus_iff         -> dvd_minus_iff
  2331 mod_add1_eq            -> mod_add_eq
  2332 mod_mult1_eq           -> mod_mult_right_eq
  2333 mod_mult1_eq'          -> mod_mult_left_eq
  2334 mod_mult_distrib_mod   -> mod_mult_eq
  2335 nat_mod_add_left_eq    -> mod_add_left_eq
  2336 nat_mod_add_right_eq   -> mod_add_right_eq
  2337 nat_mod_div_trivial    -> mod_div_trivial
  2338 nat_mod_mod_trivial    -> mod_mod_trivial
  2339 zdiv_zadd_self1        -> div_add_self1
  2340 zdiv_zadd_self2        -> div_add_self2
  2341 zdiv_zmult_self1       -> div_mult_self2_is_id
  2342 zdiv_zmult_self2       -> div_mult_self1_is_id
  2343 zdvd_triv_left         -> dvd_triv_left
  2344 zdvd_triv_right        -> dvd_triv_right
  2345 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  2346 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  2347 zmod_zadd_left_eq      -> mod_add_left_eq
  2348 zmod_zadd_right_eq     -> mod_add_right_eq
  2349 zmod_zadd_self1        -> mod_add_self1
  2350 zmod_zadd_self2        -> mod_add_self2
  2351 zmod_zadd1_eq          -> mod_add_eq
  2352 zmod_zdiff1_eq         -> mod_diff_eq
  2353 zmod_zdvd_zmod         -> mod_mod_cancel
  2354 zmod_zmod_cancel       -> mod_mod_cancel
  2355 zmod_zmult_self1       -> mod_mult_self2_is_0
  2356 zmod_zmult_self2       -> mod_mult_self1_is_0
  2357 zmod_1                 -> mod_by_1
  2358 zdiv_1                 -> div_by_1
  2359 zdvd_abs1              -> abs_dvd_iff
  2360 zdvd_abs2              -> dvd_abs_iff
  2361 zdvd_refl              -> dvd_refl
  2362 zdvd_trans             -> dvd_trans
  2363 zdvd_zadd              -> dvd_add
  2364 zdvd_zdiff             -> dvd_diff
  2365 zdvd_zminus_iff        -> dvd_minus_iff
  2366 zdvd_zminus2_iff       -> minus_dvd_iff
  2367 zdvd_zmultD            -> dvd_mult_right
  2368 zdvd_zmultD2           -> dvd_mult_left
  2369 zdvd_zmult_mono        -> mult_dvd_mono
  2370 zdvd_0_right           -> dvd_0_right
  2371 zdvd_0_left            -> dvd_0_left_iff
  2372 zdvd_1_left            -> one_dvd
  2373 zminus_dvd_iff         -> minus_dvd_iff
  2374 
  2375 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  2376 
  2377 * The real numbers offer decimal input syntax: 12.34 is translated
  2378 into 1234/10^2. This translation is not reversed upon output.
  2379 
  2380 * Theory Library/Polynomial defines an abstract type 'a poly of
  2381 univariate polynomials with coefficients of type 'a.  In addition to
  2382 the standard ring operations, it also supports div and mod.  Code
  2383 generation is also supported, using list-style constructors.
  2384 
  2385 * Theory Library/Inner_Product defines a class of real_inner for real
  2386 inner product spaces, with an overloaded operation inner :: 'a => 'a
  2387 => real.  Class real_inner is a subclass of real_normed_vector from
  2388 theory RealVector.
  2389 
  2390 * Theory Library/Product_Vector provides instances for the product
  2391 type 'a * 'b of several classes from RealVector and Inner_Product.
  2392 Definitions of addition, subtraction, scalar multiplication, norms,
  2393 and inner products are included.
  2394 
  2395 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  2396 addition to the field operations, numerals and case syntax are also
  2397 supported.
  2398 
  2399 * Theory Library/Diagonalize provides constructive version of Cantor's
  2400 first diagonalization argument.
  2401 
  2402 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  2403 zlcm (for int); carried together from various gcd/lcm developements in
  2404 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  2405 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  2406 may recover tupled syntax as follows:
  2407 
  2408     hide (open) const gcd
  2409     abbreviation gcd where
  2410       "gcd == (%(a, b). GCD.gcd a b)"
  2411     notation (output)
  2412       GCD.gcd ("gcd '(_, _')")
  2413 
  2414 The same works for lcm, zgcd, zlcm.
  2415 
  2416 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  2417 instantiations for algebraic structures.  Removed some duplicate
  2418 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  2419 
  2420 * ML antiquotation @{code} takes a constant as argument and generates
  2421 corresponding code in background and inserts name of the corresponding
  2422 resulting ML value/function/datatype constructor binding in place.
  2423 All occurrences of @{code} with a single ML block are generated
  2424 simultaneously.  Provides a generic and safe interface for
  2425 instrumentalizing code generation.  See
  2426 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  2427 In future you ought to refrain from ad-hoc compiling generated SML
  2428 code on the ML toplevel.  Note that (for technical reasons) @{code}
  2429 cannot refer to constants for which user-defined serializations are
  2430 set.  Refer to the corresponding ML counterpart directly in that
  2431 cases.
  2432 
  2433 * Command 'rep_datatype': instead of theorem names the command now
  2434 takes a list of terms denoting the constructors of the type to be
  2435 represented as datatype.  The characteristic theorems have to be
  2436 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  2437 have disappeared in favour of existing ones:
  2438 
  2439     unit_induct                 ~> unit.induct
  2440     prod_induct                 ~> prod.induct
  2441     sum_induct                  ~> sum.induct
  2442     Suc_Suc_eq                  ~> nat.inject
  2443     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  2444 
  2445 
  2446 *** HOL-Algebra ***
  2447 
  2448 * New locales for orders and lattices where the equivalence relation
  2449 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  2450 locales use a record structure with field eq for the equivalence.
  2451 
  2452 * New theory of factorial domains.
  2453 
  2454 * Units_l_inv and Units_r_inv are now simp rules by default.
  2455 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  2456 and/or r_inv will now also require deletion of these lemmas.
  2457 
  2458 * Renamed the following theorems, INCOMPATIBILITY:
  2459 
  2460 UpperD ~> Upper_memD
  2461 LowerD ~> Lower_memD
  2462 least_carrier ~> least_closed
  2463 greatest_carrier ~> greatest_closed
  2464 greatest_Lower_above ~> greatest_Lower_below
  2465 one_zero ~> carrier_one_zero
  2466 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  2467 
  2468 
  2469 *** HOL-Nominal ***
  2470 
  2471 * Nominal datatypes can now contain type-variables.
  2472 
  2473 * Commands 'nominal_inductive' and 'equivariance' work with local
  2474 theory targets.
  2475 
  2476 * Nominal primrec can now works with local theory targets and its
  2477 specification syntax now conforms to the general format as seen in
  2478 'inductive' etc.
  2479 
  2480 * Method "perm_simp" honours the standard simplifier attributes
  2481 (no_asm), (no_asm_use) etc.
  2482 
  2483 * The new predicate #* is defined like freshness, except that on the
  2484 left hand side can be a set or list of atoms.
  2485 
  2486 * Experimental command 'nominal_inductive2' derives strong induction
  2487 principles for inductive definitions.  In contrast to
  2488 'nominal_inductive', which can only deal with a fixed number of
  2489 binders, it can deal with arbitrary expressions standing for sets of
  2490 atoms to be avoided.  The only inductive definition we have at the
  2491 moment that needs this generalisation is the typing rule for Lets in
  2492 the algorithm W:
  2493 
  2494  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  2495  -----------------------------------------------------------------
  2496          Gamma |- Let x be t1 in t2 : T2
  2497 
  2498 In this rule one wants to avoid all the binders that are introduced by
  2499 "close Gamma T1".  We are looking for other examples where this
  2500 feature might be useful.  Please let us know.
  2501 
  2502 
  2503 *** HOLCF ***
  2504 
  2505 * Reimplemented the simplification procedure for proving continuity
  2506 subgoals.  The new simproc is extensible; users can declare additional
  2507 continuity introduction rules with the attribute [cont2cont].
  2508 
  2509 * The continuity simproc now uses a different introduction rule for
  2510 solving continuity subgoals on terms with lambda abstractions.  In
  2511 some rare cases the new simproc may fail to solve subgoals that the
  2512 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  2513 Potential INCOMPATIBILITY.
  2514 
  2515 * Command 'fixrec': specification syntax now conforms to the general
  2516 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  2517 examples.  INCOMPATIBILITY.
  2518 
  2519 
  2520 *** ZF ***
  2521 
  2522 * Proof of Zorn's Lemma for partial orders.
  2523 
  2524 
  2525 *** ML ***
  2526 
  2527 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  2528 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  2529 depends on multithreading, so timouts will not work before Poly/ML
  2530 5.2.1!
  2531 
  2532 * High-level support for concurrent ML programming, see
  2533 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  2534 particularly convenient to organize independent functional
  2535 computations.  The concept of "synchronized variables" provides a
  2536 higher-order interface for components with shared state, avoiding the
  2537 delicate details of mutexes and condition variables.  (Requires
  2538 Poly/ML 5.2.1 or later.)
  2539 
  2540 * ML bindings produced via Isar commands are stored within the Isar
  2541 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2542 become thread-safe and work with undo as expected (concerning
  2543 top-level bindings, not side-effects on global references).
  2544 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2545 compiler at runtime; really global bindings need to be given outside a
  2546 theory.  (Requires Poly/ML 5.2 or later.)
  2547 
  2548 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2549 context.  Top-level ML bindings are stored within the proof context in
  2550 a purely sequential fashion, disregarding the nested proof structure.
  2551 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2552 proof.  (Requires Poly/ML 5.2 or later.)
  2553 
  2554 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2555 and Method.setup, as well as Isar commands 'attribute_setup' and
  2556 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2557 existing code accordingly, or use plain 'setup' together with old
  2558 Method.add_method.
  2559 
  2560 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2561 to 'a -> thm, while results are always tagged with an authentic oracle
  2562 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2563 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2564 accordingly.  Note that extra performance may be gained by producing
  2565 the cterm carefully, avoiding slow Thm.cterm_of.
  2566 
  2567 * Simplified interface for defining document antiquotations via
  2568 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2569 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2570 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2571 examples.
  2572 
  2573 * More systematic treatment of long names, abstract name bindings, and
  2574 name space operations.  Basic operations on qualified names have been
  2575 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2576 Long_Name.append.  Old type bstring has been mostly replaced by
  2577 abstract type binding (see structure Binding), which supports precise
  2578 qualification by packages and local theory targets, as well as proper
  2579 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2580 bstring values into Binding.name, or better pass through abstract
  2581 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2582 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2583 
  2584 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2585 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2586 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2587 
  2588 * Disposed old type and term read functions (Sign.read_def_typ,
  2589 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2590 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2591 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2592 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2593 resort for legacy applications.
  2594 
  2595 * Disposed old declarations, tactics, tactic combinators that refer to
  2596 the simpset or claset of an implicit theory (such as Addsimps,
  2597 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2598 embedded ML text, or local_simpset_of with a proper context passed as
  2599 explicit runtime argument.
  2600 
  2601 * Rules and tactics that read instantiations (read_instantiate,
  2602 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2603 context, which is required for parsing and type-checking.  Moreover,
  2604 the variables are specified as plain indexnames, not string encodings
  2605 thereof.  INCOMPATIBILITY.
  2606 
  2607 * Generic Toplevel.add_hook interface allows to analyze the result of
  2608 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2609 for theorem dependency output of transactions resulting in a new
  2610 theory state.
  2611 
  2612 * ML antiquotations: block-structured compilation context indicated by
  2613 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2614 
  2615   @{binding name}                         - basic name binding
  2616   @{let ?pat = term}                      - term abbreviation (HO matching)
  2617   @{note name = fact}                     - fact abbreviation
  2618   @{thm fact}                             - singleton fact (with attributes)
  2619   @{thms fact}                            - general fact (with attributes)
  2620   @{lemma prop by method}                 - singleton goal
  2621   @{lemma prop by meth1 meth2}            - singleton goal
  2622   @{lemma prop1 ... propN by method}      - general goal
  2623   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2624   @{lemma (open) ...}                     - open derivation
  2625 
  2626 
  2627 *** System ***
  2628 
  2629 * The Isabelle "emacs" tool provides a specific interface to invoke
  2630 Proof General / Emacs, with more explicit failure if that is not
  2631 installed (the old isabelle-interface script silently falls back on
  2632 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2633 installation location of the Proof General distribution.
  2634 
  2635 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2636 the Isabelle process into a JVM/Scala application.  See
  2637 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2638 process wrapper has been discontinued.)
  2639 
  2640 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2641 
  2642 * Various status messages (with exact source position information) are
  2643 emitted, if proper markup print mode is enabled.  This allows
  2644 user-interface components to provide detailed feedback on internal
  2645 prover operations.
  2646 
  2647 
  2648 
  2649 New in Isabelle2008 (June 2008)
  2650 -------------------------------
  2651 
  2652 *** General ***
  2653 
  2654 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2655 and updated, with formally checked references as hyperlinks.
  2656 
  2657 * Theory loader: use_thy (and similar operations) no longer set the
  2658 implicit ML context, which was occasionally hard to predict and in
  2659 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2660 provides a proper context already.
  2661 
  2662 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2663 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2664 'use' within a theory file will do the job.
  2665 
  2666 * Name space merge now observes canonical order, i.e. the second space
  2667 is inserted into the first one, while existing entries in the first
  2668 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2669 swap theory imports.
  2670 
  2671 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2672 INCOMPATIBILITY in identifier syntax etc.
  2673 
  2674 * Outer syntax: string tokens no longer admit escaped white space,
  2675 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  2676 white space without escapes.
  2677 
  2678 * Outer syntax: string tokens may contain arbitrary character codes
  2679 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  2680 "foo_bar".
  2681 
  2682 
  2683 *** Pure ***
  2684 
  2685 * Context-dependent token translations.  Default setup reverts locally
  2686 fixed variables, and adds hilite markup for undeclared frees.
  2687 
  2688 * Unused theorems can be found using the new command 'unused_thms'.
  2689 There are three ways of invoking it:
  2690 
  2691 (1) unused_thms
  2692      Only finds unused theorems in the current theory.
  2693 
  2694 (2) unused_thms thy_1 ... thy_n -
  2695      Finds unused theorems in the current theory and all of its ancestors,
  2696      excluding the theories thy_1 ... thy_n and all of their ancestors.
  2697 
  2698 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  2699      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  2700      their ancestors, excluding the theories thy_1 ... thy_n and all of
  2701      their ancestors.
  2702 
  2703 In order to increase the readability of the list produced by
  2704 unused_thms, theorems that have been created by a particular instance
  2705 of a theory command such as 'inductive' or 'function' are considered
  2706 to belong to the same "group", meaning that if at least one theorem in
  2707 this group is used, the other theorems in the same group are no longer
  2708 reported as unused.  Moreover, if all theorems in the group are
  2709 unused, only one theorem in the group is displayed.
  2710 
  2711 Note that proof objects have to be switched on in order for
  2712 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  2713 usually the case when using Proof General with the default settings).
  2714 
  2715 * Authentic naming of facts disallows ad-hoc overwriting of previous
  2716 theorems within the same name space.  INCOMPATIBILITY, need to remove
  2717 duplicate fact bindings, or even accidental fact duplications.  Note
  2718 that tools may maintain dynamically scoped facts systematically, using
  2719 PureThy.add_thms_dynamic.
  2720 
  2721 * Command 'hide' now allows to hide from "fact" name space as well.
  2722 
  2723 * Eliminated destructive theorem database, simpset, claset, and
  2724 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  2725 update of theories within ML code.
  2726 
  2727 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  2728 INCOMPATIBILITY, object-logics depending on former Pure require
  2729 additional setup PureThy.old_appl_syntax_setup; object-logics
  2730 depending on former CPure need to refer to Pure.
  2731 
  2732 * Commands 'use' and 'ML' are now purely functional, operating on
  2733 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  2734 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  2735 INCOMPATIBILITY.
  2736 
  2737 * Command 'setup': discontinued implicit version with ML reference.
  2738 
  2739 * Instantiation target allows for simultaneous specification of class
  2740 instance operations together with an instantiation proof.
  2741 Type-checking phase allows to refer to class operations uniformly.
  2742 See src/HOL/Complex/Complex.thy for an Isar example and
  2743 src/HOL/Library/Eval.thy for an ML example.
  2744 
  2745 * Indexing of literal facts: be more serious about including only
  2746 facts from the visible specification/proof context, but not the
  2747 background context (locale etc.).  Affects `prop` notation and method
  2748 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  2749 situations.
  2750 
  2751 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  2752 "(open)" option, which used to expose internal bound variables to the
  2753 proof text.
  2754 
  2755 * Isar statements: removed obsolete case "rule_context".
  2756 INCOMPATIBILITY, better use explicit fixes/assumes.
  2757 
  2758 * Locale proofs: default proof step now includes 'unfold_locales';
  2759 hence 'proof' without argument may be used to unfold locale
  2760 predicates.
  2761 
  2762 
  2763 *** Document preparation ***
  2764 
  2765 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  2766 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  2767 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  2768 spot); renamed link color from "darkblue" to "linkcolor" (default
  2769 value unchanged, can be redefined via \definecolor); no longer sets
  2770 "a4paper" option (unnecessary or even intrusive).
  2771 
  2772 * Antiquotation @{lemma A method} proves proposition A by the given
  2773 method (either a method name or a method name plus (optional) method
  2774 arguments in parentheses) and prints A just like @{prop A}.
  2775 
  2776 
  2777 *** HOL ***
  2778 
  2779 * New primrec package.  Specification syntax conforms in style to
  2780 definition/function/....  No separate induction rule is provided.  The
  2781 "primrec" command distinguishes old-style and new-style specifications
  2782 by syntax.  The former primrec package is now named OldPrimrecPackage.
  2783 When adjusting theories, beware: constants stemming from new-style
  2784 primrec specifications have authentic syntax.
  2785 
  2786 * Metis prover is now an order of magnitude faster, and also works
  2787 with multithreading.
  2788 
  2789 * Metis: the maximum number of clauses that can be produced from a
  2790 theorem is now given by the attribute max_clauses.  Theorems that
  2791 exceed this number are ignored, with a warning printed.
  2792 
  2793 * Sledgehammer no longer produces structured proofs by default. To
  2794 enable, declare [[sledgehammer_full = true]].  Attributes
  2795 reconstruction_modulus, reconstruction_sorts renamed
  2796 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  2797 
  2798 * Method "induct_scheme" derives user-specified induction rules
  2799 from well-founded induction and completeness of patterns. This factors
  2800 out some operations that are done internally by the function package
  2801 and makes them available separately.  See
  2802 src/HOL/ex/Induction_Scheme.thy for examples.
  2803 
  2804 * More flexible generation of measure functions for termination
  2805 proofs: Measure functions can be declared by proving a rule of the
  2806 form "is_measure f" and giving it the [measure_function] attribute.
  2807 The "is_measure" predicate is logically meaningless (always true), and
  2808 just guides the heuristic.  To find suitable measure functions, the
  2809 termination prover sets up the goal "is_measure ?f" of the appropriate
  2810 type and generates all solutions by prolog-style backwards proof using
  2811 the declared rules.
  2812 
  2813 This setup also deals with rules like 
  2814 
  2815   "is_measure f ==> is_measure (list_size f)"
  2816 
  2817 which accommodates nested datatypes that recurse through lists.
  2818 Similar rules are predeclared for products and option types.
  2819 
  2820 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  2821 
  2822   INCOMPATIBILITIES:
  2823 
  2824   - Definitions of overloaded constants on sets have to be replaced by
  2825     definitions on => and bool.
  2826 
  2827   - Some definitions of overloaded operators on sets can now be proved
  2828     using the definitions of the operators on => and bool.  Therefore,
  2829     the following theorems have been renamed:
  2830 
  2831       subset_def   -> subset_eq
  2832       psubset_def  -> psubset_eq
  2833       set_diff_def -> set_diff_eq
  2834       Compl_def    -> Compl_eq
  2835       Sup_set_def  -> Sup_set_eq
  2836       Inf_set_def  -> Inf_set_eq
  2837       sup_set_def  -> sup_set_eq
  2838       inf_set_def  -> inf_set_eq
  2839 
  2840   - Due to the incompleteness of the HO unification algorithm, some
  2841     rules such as subst may require manual instantiation, if some of
  2842     the unknowns in the rule is a set.
  2843 
  2844   - Higher order unification and forward proofs:
  2845     The proof pattern
  2846 
  2847       have "P (S::'a set)" <...>
  2848       then have "EX S. P S" ..
  2849 
  2850     no longer works (due to the incompleteness of the HO unification
  2851     algorithm) and must be replaced by the pattern
  2852 
  2853       have "EX S. P S"
  2854       proof
  2855         show "P S" <...>
  2856       qed
  2857 
  2858   - Calculational reasoning with subst (or similar rules):
  2859     The proof pattern
  2860 
  2861       have "P (S::'a set)" <...>
  2862       also have "S = T" <...>
  2863       finally have "P T" .
  2864 
  2865     no longer works (for similar reasons as the previous example) and
  2866     must be replaced by something like
  2867 
  2868       have "P (S::'a set)" <...>
  2869       moreover have "S = T" <...>
  2870       ultimately have "P T" by simp
  2871 
  2872   - Tactics or packages written in ML code:
  2873     Code performing pattern matching on types via
  2874 
  2875       Type ("set", [T]) => ...
  2876 
  2877     must be rewritten. Moreover, functions like strip_type or
  2878     binder_types no longer return the right value when applied to a
  2879     type of the form
  2880 
  2881       T1 => ... => Tn => U => bool
  2882 
  2883     rather than
  2884 
  2885       T1 => ... => Tn => U set
  2886 
  2887 * Merged theories Wellfounded_Recursion, Accessible_Part and
  2888 Wellfounded_Relations to theory Wellfounded.
  2889 
  2890 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  2891 
  2892 * Class finite no longer treats UNIV as class parameter.  Use class
  2893 enum from theory Library/Enum instead to achieve a similar effect.
  2894 INCOMPATIBILITY.
  2895 
  2896 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  2897 and "Cons".  INCOMPATIBILITY.
  2898 
  2899 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  2900 Potential INCOMPATIBILITY.
  2901 
  2902 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  2903 injective_fst_snd removed, use split_eta and prod_eqI instead.
  2904 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  2905 
  2906 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  2907 the same name in theory Orderings:
  2908 
  2909   less_trans
  2910   less_linear
  2911   le_imp_less_or_eq
  2912   le_less_trans
  2913   less_le_trans
  2914   less_not_sym
  2915   less_asym
  2916 
  2917 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  2918 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  2919 and different variable names.
  2920 
  2921 * Library/Option_ord.thy: Canonical order on option type.
  2922 
  2923 * Library/RBT.thy: Red-black trees, an efficient implementation of
  2924 finite maps.
  2925 
  2926 * Library/Countable.thy: Type class for countable types.
  2927 
  2928 * Theory Int: The representation of numerals has changed.  The infix
  2929 operator BIT and the bit datatype with constructors B0 and B1 have
  2930 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  2931 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  2932 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  2933 accordingly.
  2934 
  2935 * Theory Nat: definition of <= and < on natural numbers no longer
  2936 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  2937 le_def and less_def have disappeared.  Consider lemmas not_less
  2938 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  2939 
  2940 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  2941 (whose purpose mainly is for various fold_set functionals) have been
  2942 abandoned in favor of the existing algebraic classes
  2943 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  2944 lower_semilattice (resp. upper_semilattice) and linorder.
  2945 INCOMPATIBILITY.
  2946 
  2947 * Theory Transitive_Closure: induct and cases rules now declare proper
  2948 case_names ("base" and "step").  INCOMPATIBILITY.
  2949 
  2950 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  2951 lattices.  The form set-specific version is available as
  2952 Inductive.lfp_ordinal_induct_set.
  2953 
  2954 * Renamed theorems "power.simps" to "power_int.simps".
  2955 INCOMPATIBILITY.
  2956 
  2957 * Class semiring_div provides basic abstract properties of semirings
  2958 with division and modulo operations.  Subsumes former class dvd_mod.
  2959 
  2960 * Merged theories IntDef, Numeral and IntArith into unified theory
  2961 Int.  INCOMPATIBILITY.
  2962 
  2963 * Theory Library/Code_Index: type "index" now represents natural
  2964 numbers rather than integers.  INCOMPATIBILITY.
  2965 
  2966 * New class "uminus" with operation "uminus" (split of from class
  2967 "minus" which now only has operation "minus", binary).
  2968 INCOMPATIBILITY.
  2969 
  2970 * Constants "card", "internal_split", "option_map" now with authentic
  2971 syntax.  INCOMPATIBILITY.
  2972 
  2973 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  2974 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  2975 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  2976 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  2977 Sup_set_def, le_def, less_def, option_map_def now with object
  2978 equality.  INCOMPATIBILITY.
  2979 
  2980 * Records. Removed K_record, and replaced it by pure lambda term
  2981 %x. c. The simplifier setup is now more robust against eta expansion.
  2982 INCOMPATIBILITY: in cases explicitly referring to K_record.
  2983 
  2984 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  2985 
  2986 * Library/ListVector: new theory of arithmetic vector operations.
  2987 
  2988 * Library/Order_Relation: new theory of various orderings as sets of
  2989 pairs.  Defines preorders, partial orders, linear orders and
  2990 well-orders on sets and on types.
  2991 
  2992 
  2993 *** ZF ***
  2994 
  2995 * Renamed some theories to allow to loading both ZF and HOL in the
  2996 same session:
  2997 
  2998   Datatype  -> Datatype_ZF
  2999   Inductive -> Inductive_ZF
  3000   Int       -> Int_ZF
  3001   IntDiv    -> IntDiv_ZF
  3002   Nat       -> Nat_ZF
  3003   List      -> List_ZF
  3004   Main      -> Main_ZF
  3005 
  3006 INCOMPATIBILITY: ZF theories that import individual theories below
  3007 Main might need to be adapted.  Regular theory Main is still
  3008 available, as trivial extension of Main_ZF.
  3009 
  3010 
  3011 *** ML ***
  3012 
  3013 * ML within Isar: antiquotation @{const name} or @{const
  3014 name(typargs)} produces statically-checked Const term.
  3015 
  3016 * Functor NamedThmsFun: data is available to the user as dynamic fact
  3017 (of the same name).  Removed obsolete print command.
  3018 
  3019 * Removed obsolete "use_legacy_bindings" function.
  3020 
  3021 * The ``print mode'' is now a thread-local value derived from a global
  3022 template (the former print_mode reference), thus access becomes
  3023 non-critical.  The global print_mode reference is for session
  3024 management only; user-code should use print_mode_value,
  3025 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  3026 
  3027 * Functions system/system_out provide a robust way to invoke external
  3028 shell commands, with propagation of interrupts (requires Poly/ML
  3029 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  3030 
  3031 
  3032 *** System ***
  3033 
  3034 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  3035 in accordance with Proof General 3.7, which prefers GNU emacs.
  3036 
  3037 * isatool tty runs Isabelle process with plain tty interaction;
  3038 optional line editor may be specified via ISABELLE_LINE_EDITOR
  3039 setting, the default settings attempt to locate "ledit" and "rlwrap".
  3040 
  3041 * isatool browser now works with Cygwin as well, using general
  3042 "javapath" function defined in Isabelle process environment.
  3043 
  3044 * YXML notation provides a simple and efficient alternative to
  3045 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  3046 isatool yxml as described in the Isabelle system manual.
  3047 
  3048 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  3049 provides general wrapper for managing an Isabelle process in a robust
  3050 fashion, with ``cooked'' output from stdin/stderr.
  3051 
  3052 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  3053 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  3054 
  3055 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  3056 way of changing the user's settings is via
  3057 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  3058 script.
  3059 
  3060 * Multithreading.max_threads := 0 refers to the number of actual CPU
  3061 cores of the underlying machine, which is a good starting point for
  3062 optimal performance tuning.  The corresponding usedir option -M allows
  3063 "max" as an alias for "0".  WARNING: does not work on certain versions
  3064 of Mac OS (with Poly/ML 5.1).
  3065 
  3066 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  3067 adverse effect of Isabelle flooding interactive front-ends (notably
  3068 ProofGeneral / XEmacs).
  3069 
  3070 
  3071 
  3072 New in Isabelle2007 (November 2007)
  3073 -----------------------------------
  3074 
  3075 *** General ***
  3076 
  3077 * More uniform information about legacy features, notably a
  3078 warning/error of "Legacy feature: ...", depending on the state of the
  3079 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  3080 legacy features will disappear eventually.
  3081 
  3082 * Theory syntax: the header format ``theory A = B + C:'' has been
  3083 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  3084 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  3085 
  3086 * Theory syntax: the old non-Isar theory file format has been
  3087 discontinued altogether.  Note that ML proof scripts may still be used
  3088 with Isar theories; migration is usually quite simple with the ML
  3089 function use_legacy_bindings.  INCOMPATIBILITY.
  3090 
  3091 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  3092 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  3093 quotes.
  3094 
  3095 * Theory loader: be more serious about observing the static theory
  3096 header specifications (including optional directories), but not the
  3097 accidental file locations of previously successful loads.  The strict
  3098 update policy of former update_thy is now already performed by
  3099 use_thy, so the former has been removed; use_thys updates several
  3100 theories simultaneously, just as 'imports' within a theory header
  3101 specification, but without merging the results.  Potential
  3102 INCOMPATIBILITY: may need to refine theory headers and commands
  3103 ROOT.ML which depend on load order.
  3104 
  3105 * Theory loader: optional support for content-based file
  3106 identification, instead of the traditional scheme of full physical
  3107 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  3108 (cf. the system manual).  The new scheme allows to work with
  3109 non-finished theories in persistent session images, such that source
  3110 files may be moved later on without requiring reloads.
  3111 
  3112 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3113 file (with the same base name as the theory) are considered a legacy
  3114 feature, which will disappear eventually. Even now, the theory loader
  3115 no longer maintains dependencies on such files.
  3116 
  3117 * Syntax: the scope for resolving ambiguities via type-inference is
  3118 now limited to individual terms, instead of whole simultaneous
  3119 specifications as before. This greatly reduces the complexity of the
  3120 syntax module and improves flexibility by separating parsing and
  3121 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  3122 'fixes' etc.) are required in rare situations.
  3123 
  3124 * Syntax: constants introduced by new-style packages ('definition',
  3125 'abbreviation' etc.) are passed through the syntax module in
  3126 ``authentic mode''. This means that associated mixfix annotations
  3127 really stick to such constants, independently of potential name space
  3128 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  3129 trees are represented slightly differently, may need to adapt syntax
  3130 translations accordingly. Use CONST marker in 'translations' and
  3131 @{const_syntax} antiquotation in 'parse_translation' etc.
  3132 
  3133 * Legacy goal package: reduced interface to the bare minimum required
  3134 to keep existing proof scripts running.  Most other user-level
  3135 functions are now part of the OldGoals structure, which is *not* open
  3136 by default (consider isatool expandshort before open OldGoals).
  3137 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  3138 these tend to cause confusion about the actual goal (!) context being
  3139 used here, which is not necessarily the same as the_context().
  3140 
  3141 * Command 'find_theorems': supports "*" wild-card in "name:"
  3142 criterion; "with_dups" option.  Certain ProofGeneral versions might
  3143 support a specific search form (see ProofGeneral/CHANGES).
  3144 
  3145 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  3146 by default, which means that "prems" (and also "fixed variables") are
  3147 suppressed from proof state output.  Note that the ProofGeneral
  3148 settings mechanism allows to change and save options persistently, but
  3149 older versions of Isabelle will fail to start up if a negative prems
  3150 limit is imposed.
  3151 
  3152 * Local theory targets may be specified by non-nested blocks of
  3153 ``context/locale/class ... begin'' followed by ``end''.  The body may
  3154 contain definitions, theorems etc., including any derived mechanism
  3155 that has been implemented on top of these primitives.  This concept
  3156 generalizes the existing ``theorem (in ...)'' towards more versatility
  3157 and scalability.
  3158 
  3159 * Proof General interface: proper undo of final 'end' command;
  3160 discontinued Isabelle/classic mode (ML proof scripts).
  3161 
  3162 
  3163 *** Document preparation ***
  3164 
  3165 * Added antiquotation @{theory name} which prints the given name,
  3166 after checking that it refers to a valid ancestor theory in the
  3167 current context.
  3168 
  3169 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  3170 check the given source text as ML type/structure, printing verbatim.
  3171 
  3172 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  3173 "c args == rhs" given in the current context.  (Any number of
  3174 arguments may be given on the LHS.)
  3175 
  3176 
  3177 *** Pure ***
  3178 
  3179 * The 'class' package offers a combination of axclass and locale to
  3180 achieve Haskell-like type classes in Isabelle.  Definitions and
  3181 theorems within a class context produce both relative results (with
  3182 implicit parameters according to the locale context), and polymorphic
  3183 constants with qualified polymorphism (according to the class
  3184 context).  Within the body context of a 'class' target, a separate
  3185 syntax layer ("user space type system") takes care of converting
  3186 between global polymorphic consts and internal locale representation.
  3187 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  3188 "isatool doc classes" provides a tutorial.
  3189 
  3190 * Generic code generator framework allows to generate executable
  3191 code for ML and Haskell (including Isabelle classes).  A short usage
  3192 sketch:
  3193 
  3194     internal compilation:
  3195         export_code <list of constants (term syntax)> in SML
  3196     writing SML code to a file:
  3197         export_code <list of constants (term syntax)> in SML <filename>
  3198     writing OCaml code to a file:
  3199         export_code <list of constants (term syntax)> in OCaml <filename>
  3200     writing Haskell code to a bunch of files:
  3201         export_code <list of constants (term syntax)> in Haskell <filename>
  3202 
  3203     evaluating closed propositions to True/False using code generation:
  3204         method ``eval''
  3205 
  3206 Reasonable default setup of framework in HOL.
  3207 
  3208 Theorem attributs for selecting and transforming function equations theorems:
  3209 
  3210     [code fun]:        select a theorem as function equation for a specific constant
  3211     [code fun del]:    deselect a theorem as function equation for a specific constant
  3212     [code inline]:     select an equation theorem for unfolding (inlining) in place
  3213     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  3214 
  3215 User-defined serializations (target in {SML, OCaml, Haskell}):
  3216 
  3217     code_const <and-list of constants (term syntax)>
  3218       {(target) <and-list of const target syntax>}+
  3219 
  3220     code_type <and-list of type constructors>
  3221       {(target) <and-list of type target syntax>}+
  3222 
  3223     code_instance <and-list of instances>
  3224       {(target)}+
  3225         where instance ::= <type constructor> :: <class>
  3226 
  3227     code_class <and_list of classes>
  3228       {(target) <and-list of class target syntax>}+
  3229         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  3230 
  3231 code_instance and code_class only are effective to target Haskell.
  3232 
  3233 For example usage see src/HOL/ex/Codegenerator.thy and
  3234 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  3235 generation from Isabelle/HOL theories is available via "isatool doc
  3236 codegen".
  3237 
  3238 * Code generator: consts in 'consts_code' Isar commands are now
  3239 referred to by usual term syntax (including optional type
  3240 annotations).
  3241 
  3242 * Command 'no_translations' removes translation rules from theory
  3243 syntax.
  3244 
  3245 * Overloaded definitions are now actually checked for acyclic
  3246 dependencies.  The overloading scheme is slightly more general than
  3247 that of Haskell98, although Isabelle does not demand an exact
  3248 correspondence to type class and instance declarations.
  3249 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  3250 exotic versions of overloading -- at the discretion of the user!
  3251 
  3252 Polymorphic constants are represented via type arguments, i.e. the
  3253 instantiation that matches an instance against the most general
  3254 declaration given in the signature.  For example, with the declaration
  3255 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  3256 as c(nat).  Overloading is essentially simultaneous structural
  3257 recursion over such type arguments.  Incomplete specification patterns
  3258 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  3259 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  3260 Command 'print_theory' outputs the normalized system of recursive
  3261 equations, see section "definitions".
  3262 
  3263 * Configuration options are maintained within the theory or proof
  3264 context (with name and type bool/int/string), providing a very simple
  3265 interface to a poor-man's version of general context data.  Tools may
  3266 declare options in ML (e.g. using Attrib.config_int) and then refer to
  3267 these values using Config.get etc.  Users may change options via an
  3268 associated attribute of the same name.  This form of context
  3269 declaration works particularly well with commands 'declare' or
  3270 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  3271 very easy to avoid global references, which would not observe Isar
  3272 toplevel undo/redo and fail to work with multithreading.
  3273 
  3274 Various global ML references of Pure and HOL have been turned into
  3275 configuration options:
  3276 
  3277   Unify.search_bound		unify_search_bound
  3278   Unify.trace_bound		unify_trace_bound
  3279   Unify.trace_simp		unify_trace_simp
  3280   Unify.trace_types		unify_trace_types
  3281   Simplifier.simp_depth_limit	simp_depth_limit
  3282   Blast.depth_limit		blast_depth_limit
  3283   DatatypeProp.dtK		datatype_distinctness_limit
  3284   fast_arith_neq_limit  	fast_arith_neq_limit
  3285   fast_arith_split_limit	fast_arith_split_limit
  3286 
  3287 * Named collections of theorems may be easily installed as context
  3288 data using the functor NamedThmsFun (see also
  3289 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  3290 attributes; there is also a toplevel print command.  This facility is
  3291 just a common case of general context data, which is the preferred way
  3292 for anything more complex than just a list of facts in canonical
  3293 order.
  3294 
  3295 * Isar: command 'declaration' augments a local theory by generic
  3296 declaration functions written in ML.  This enables arbitrary content
  3297 being added to the context, depending on a morphism that tells the
  3298 difference of the original declaration context wrt. the application
  3299 context encountered later on.
  3300 
  3301 * Isar: proper interfaces for simplification procedures.  Command
  3302 'simproc_setup' declares named simprocs (with match patterns, and body
  3303 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  3304 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  3305 
  3306 * Isar: an extra pair of brackets around attribute declarations
  3307 abbreviates a theorem reference involving an internal dummy fact,
  3308 which will be ignored later --- only the effect of the attribute on
  3309 the background context will persist.  This form of in-place
  3310 declarations is particularly useful with commands like 'declare' and
  3311 'using', for example ``have A using [[simproc a]] by simp''.
  3312 
  3313 * Isar: method "assumption" (and implicit closing of subproofs) now
  3314 takes simple non-atomic goal assumptions into account: after applying
  3315 an assumption as a rule the resulting subgoals are solved by atomic
  3316 assumption steps.  This is particularly useful to finish 'obtain'
  3317 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  3318 without referring to the original premise "!!x. P x ==> thesis" in the
  3319 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  3320 more permissive.
  3321 
  3322 * Isar: implicit use of prems from the Isar proof context is
  3323 considered a legacy feature.  Common applications like ``have A .''
  3324 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  3325 referencing facts explicitly here improves readability and
  3326 maintainability of proof texts.
  3327 
  3328 * Isar: improper proof element 'guess' is like 'obtain', but derives
  3329 the obtained context from the course of reasoning!  For example:
  3330 
  3331   assume "EX x y. A x & B y"   -- "any previous fact"
  3332   then guess x and y by clarify
  3333 
  3334 This technique is potentially adventurous, depending on the facts and
  3335 proof tools being involved here.
  3336 
  3337 * Isar: known facts from the proof context may be specified as literal
  3338 propositions, using ASCII back-quote syntax.  This works wherever
  3339 named facts used to be allowed so far, in proof commands, proof
  3340 methods, attributes etc.  Literal facts are retrieved from the context
  3341 according to unification of type and term parameters.  For example,
  3342 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  3343 theorems in the current context, then these are valid literal facts:
  3344 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  3345 
  3346 There is also a proof method "fact" which does the same composition
  3347 for explicit goal states, e.g. the following proof texts coincide with
  3348 certain special cases of literal facts:
  3349 
  3350   have "A" by fact                 ==  note `A`
  3351   have "A ==> B" by fact           ==  note `A ==> B`
  3352   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  3353   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  3354 
  3355 * Isar: ":" (colon) is no longer a symbolic identifier character in
  3356 outer syntax.  Thus symbolic identifiers may be used without
  3357 additional white space in declarations like this: ``assume *: A''.
  3358 
  3359 * Isar: 'print_facts' prints all local facts of the current context,
  3360 both named and unnamed ones.
  3361 
  3362 * Isar: 'def' now admits simultaneous definitions, e.g.:
  3363 
  3364   def x == "t" and y == "u"
  3365 
  3366 * Isar: added command 'unfolding', which is structurally similar to
  3367 'using', but affects both the goal state and facts by unfolding given
  3368 rewrite rules.  Thus many occurrences of the 'unfold' method or
  3369 'unfolded' attribute may be replaced by first-class proof text.
  3370 
  3371 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  3372 and command 'unfolding' now all support object-level equalities
  3373 (potentially conditional).  The underlying notion of rewrite rule is
  3374 analogous to the 'rule_format' attribute, but *not* that of the
  3375 Simplifier (which is usually more generous).
  3376 
  3377 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  3378 premises of a theorem by n. Useful in conjunction with drule.
  3379 
  3380 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  3381 method expression within a sandbox consisting of the first N
  3382 sub-goals, which need to exist.  For example, ``simp_all [3]''
  3383 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  3384 simplifies all new goals that emerge from applying rule foo to the
  3385 originally first one.
  3386 
  3387 * Isar: schematic goals are no longer restricted to higher-order
  3388 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  3389 expected.
  3390 
  3391 * Isar: the conclusion of a long theorem statement is now either
  3392 'shows' (a simultaneous conjunction, as before), or 'obtains'
  3393 (essentially a disjunction of cases with local parameters and
  3394 assumptions).  The latter allows to express general elimination rules
  3395 adequately; in this notation common elimination rules look like this:
  3396 
  3397   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  3398     assumes "EX x. P x"
  3399     obtains x where "P x"
  3400 
  3401   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  3402     assumes "A & B"
  3403     obtains A and B
  3404 
  3405   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  3406     assumes "A | B"
  3407     obtains
  3408       A
  3409     | B
  3410 
  3411 The subsequent classical rules even refer to the formal "thesis"
  3412 explicitly:
  3413 
  3414   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  3415     obtains "~ thesis"
  3416 
  3417   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  3418     obtains "thesis ==> something"
  3419 
  3420 The actual proof of an 'obtains' statement is analogous to that of the
  3421 Isar proof element 'obtain', only that there may be several cases.
  3422 Optional case names may be specified in parentheses; these will be
  3423 available both in the present proof and as annotations in the
  3424 resulting rule, for later use with the 'cases' method (cf. attribute
  3425 case_names).
  3426 
  3427 * Isar: the assumptions of a long theorem statement are available as
  3428 "assms" fact in the proof context.  This is more appropriate than the
  3429 (historical) "prems", which refers to all assumptions of the current
  3430 context, including those from the target locale, proof body etc.
  3431 
  3432 * Isar: 'print_statement' prints theorems from the current theory or
  3433 proof context in long statement form, according to the syntax of a
  3434 top-level lemma.
  3435 
  3436 * Isar: 'obtain' takes an optional case name for the local context
  3437 introduction rule (default "that").
  3438 
  3439 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  3440 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  3441 to occur.
  3442 
  3443 * Pure: syntax "CONST name" produces a fully internalized constant
  3444 according to the current context.  This is particularly useful for
  3445 syntax translations that should refer to internal constant
  3446 representations independently of name spaces.
  3447 
  3448 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  3449 instead of "FOO ". This allows multiple binder declarations to coexist
  3450 in the same context.  INCOMPATIBILITY.
  3451 
  3452 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  3453 primitive that also works in a locale context (both for constants and
  3454 fixed variables). Type declaration and internal syntactic representation
  3455 of given constants retrieved from the context. Likewise, the
  3456 'no_notation' command allows to remove given syntax annotations from the
  3457 current context.
  3458 
  3459 * Isar/locales: new derived specification elements 'axiomatization',
  3460 'definition', 'abbreviation', which support type-inference, admit
  3461 object-level specifications (equality, equivalence).  See also the
  3462 isar-ref manual.  Examples:
  3463 
  3464   axiomatization
  3465     eq  (infix "===" 50) where
  3466     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  3467 
  3468   definition "f x y = x + y + 1"
  3469   definition g where "g x = f x x"
  3470 
  3471   abbreviation
  3472     neq  (infix "=!=" 50) where
  3473     "x =!= y == ~ (x === y)"
  3474 
  3475 These specifications may be also used in a locale context.  Then the
  3476 constants being introduced depend on certain fixed parameters, and the
  3477 constant name is qualified by the locale base name.  An internal
  3478 abbreviation takes care for convenient input and output, making the
  3479 parameters implicit and using the original short name.  See also
  3480 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  3481 entities from a monomorphic theory.
  3482 
  3483 Presently, abbreviations are only available 'in' a target locale, but
  3484 not inherited by general import expressions.  Also note that
  3485 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  3486 'translations' in common applications.  The "no_abbrevs" print mode
  3487 prevents folding of abbreviations in term output.
  3488 
  3489 Concrete syntax is attached to specified constants in internal form,
  3490 independently of name spaces.  The parse tree representation is
  3491 slightly different -- use 'notation' instead of raw 'syntax', and
  3492 'translations' with explicit "CONST" markup to accommodate this.
  3493 
  3494 * Pure/Isar: unified syntax for new-style specification mechanisms
  3495 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  3496 full type inference and dummy patterns ("_").  For example:
  3497 
  3498   definition "K x _ = x"
  3499 
  3500   inductive conj for A B
  3501   where "A ==> B ==> conj A B"
  3502 
  3503 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  3504 the current context.  Print mode "no_abbrevs" prevents inversion of
  3505 abbreviations on output.
  3506 
  3507 * Isar/locales: improved parameter handling: use of locales "var" and
  3508 "struct" no longer necessary; - parameter renamings are no longer
  3509 required to be injective.  For example, this allows to define
  3510 endomorphisms as locale endom = homom mult mult h.
  3511 
  3512 * Isar/locales: changed the way locales with predicates are defined.
  3513 Instead of accumulating the specification, the imported expression is
  3514 now an interpretation.  INCOMPATIBILITY: different normal form of
  3515 locale expressions.  In particular, in interpretations of locales with
  3516 predicates, goals repesenting already interpreted fragments are not
  3517 removed automatically.  Use methods `intro_locales' and
  3518 `unfold_locales'; see below.
  3519 
  3520 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  3521 provide backward reasoning on locales predicates.  The methods are
  3522 aware of interpretations and discharge corresponding goals.
  3523 `intro_locales' is less aggressive then `unfold_locales' and does not
  3524 unfold predicates to assumptions.
  3525 
  3526 * Isar/locales: the order in which locale fragments are accumulated
  3527 has changed.  This enables to override declarations from fragments due
  3528 to interpretations -- for example, unwanted simp rules.
  3529 
  3530 * Isar/locales: interpretation in theories and proof contexts has been
  3531 extended.  One may now specify (and prove) equations, which are
  3532 unfolded in interpreted theorems.  This is useful for replacing
  3533 defined concepts (constants depending on locale parameters) by
  3534 concepts already existing in the target context.  Example:
  3535 
  3536   interpretation partial_order ["op <= :: [int, int] => bool"]
  3537     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3538 
  3539 Typically, the constant `partial_order.less' is created by a
  3540 definition specification element in the context of locale
  3541 partial_order.
  3542 
  3543 * Method "induct": improved internal context management to support
  3544 local fixes and defines on-the-fly. Thus explicit meta-level
  3545 connectives !!  and ==> are rarely required anymore in inductive goals
  3546 (using object-logic connectives for this purpose has been long
  3547 obsolete anyway). Common proof patterns are explained in
  3548 src/HOL/Induct/Common_Patterns.thy, see also
  3549 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3550 examples.
  3551 
  3552 * Method "induct": improved handling of simultaneous goals. Instead of
  3553 introducing object-level conjunction, the statement is now split into
  3554 several conclusions, while the corresponding symbolic cases are nested
  3555 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3556 see src/HOL/Induct/Common_Patterns.thy, for example.
  3557 
  3558 * Method "induct": mutual induction rules are now specified as a list
  3559 of rule sharing the same induction cases. HOL packages usually provide
  3560 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3561 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3562 mutual induction rules differently, i.e. like this:
  3563 
  3564   (induct rule: foo_bar.inducts)
  3565   (induct set: foo bar)
  3566   (induct pred: foo bar)
  3567   (induct type: foo bar)
  3568 
  3569 The ML function ProjectRule.projections turns old-style rules into the
  3570 new format.
  3571 
  3572 * Method "coinduct": dual of induction, see
  3573 src/HOL/Library/Coinductive_List.thy for various examples.
  3574 
  3575 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3576 considered a legacy feature.
  3577 
  3578 * Attribute "symmetric" produces result with standardized schematic
  3579 variables (index 0).  Potential INCOMPATIBILITY.
  3580 
  3581 * Simplifier: by default the simplifier trace only shows top level
  3582 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3583 default. Thus there is less danger of being flooded by the trace. The
  3584 trace indicates where parts have been suppressed.
  3585   
  3586 * Provers/classical: removed obsolete classical version of elim_format
  3587 attribute; classical elim/dest rules are now treated uniformly when
  3588 manipulating the claset.
  3589 
  3590 * Provers/classical: stricter checks to ensure that supplied intro,
  3591 dest and elim rules are well-formed; dest and elim rules must have at
  3592 least one premise.
  3593 
  3594 * Provers/classical: attributes dest/elim/intro take an optional
  3595 weight argument for the rule (just as the Pure versions).  Weights are
  3596 ignored by automated tools, but determine the search order of single
  3597 rule steps.
  3598 
  3599 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3600 where the body does not mention the bound variable.  Note that dummy
  3601 patterns implicitly depend on their context of bounds, which makes
  3602 "{_. _}" match any set comprehension as expected.  Potential
  3603 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3604 constant "_idtdummy" in the binding position.
  3605 
  3606 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3607 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3608 for example "A -> B" => "Pi A (%_. B)".
  3609 
  3610 * Pure: 'class_deps' command visualizes the subclass relation, using
  3611 the graph browser tool.
  3612 
  3613 * Pure: 'print_theory' now suppresses certain internal declarations by
  3614 default; use '!' option for full details.
  3615 
  3616 
  3617 *** HOL ***
  3618 
  3619 * Method "metis" proves goals by applying the Metis general-purpose
  3620 resolution prover (see also http://gilith.com/software/metis/).
  3621 Examples are in the directory MetisExamples.  WARNING: the
  3622 Isabelle/HOL-Metis integration does not yet work properly with
  3623 multi-threading.
  3624   
  3625 * Command 'sledgehammer' invokes external automatic theorem provers as
  3626 background processes.  It generates calls to the "metis" method if
  3627 successful. These can be pasted into the proof.  Users do not have to
  3628 wait for the automatic provers to return.  WARNING: does not really
  3629 work with multi-threading.
  3630 
  3631 * New "auto_quickcheck" feature tests outermost goal statements for
  3632 potential counter-examples.  Controlled by ML references
  3633 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3634 5000 milliseconds).  Fails silently if statements is outside of
  3635 executable fragment, or any other codgenerator problem occurs.
  3636 
  3637 * New constant "undefined" with axiom "undefined x = undefined".
  3638 
  3639 * Added class "HOL.eq", allowing for code generation with polymorphic
  3640 equality.
  3641 
  3642 * Some renaming of class constants due to canonical name prefixing in
  3643 the new 'class' package:
  3644 
  3645     HOL.abs ~> HOL.abs_class.abs
  3646     HOL.divide ~> HOL.divide_class.divide
  3647     0 ~> HOL.zero_class.zero
  3648     1 ~> HOL.one_class.one
  3649     op + ~> HOL.plus_class.plus
  3650     op - ~> HOL.minus_class.minus
  3651     uminus ~> HOL.minus_class.uminus
  3652     op * ~> HOL.times_class.times
  3653     op < ~> HOL.ord_class.less
  3654     op <= > HOL.ord_class.less_eq
  3655     Nat.power ~> Power.power_class.power
  3656     Nat.size ~> Nat.size_class.size
  3657     Numeral.number_of ~> Numeral.number_class.number_of
  3658     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3659     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3660     Orderings.min ~> Orderings.ord_class.min
  3661     Orderings.max ~> Orderings.ord_class.max
  3662     Divides.op div ~> Divides.div_class.div
  3663     Divides.op mod ~> Divides.div_class.mod
  3664     Divides.op dvd ~> Divides.div_class.dvd
  3665 
  3666 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3667 
  3668 a) User-defined constants using any of the names "plus", "minus",
  3669 "times", "less" or "less_eq". The standard syntax translations for
  3670 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3671 names.
  3672 
  3673 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3674 INCOMPATIBILITY: use more specific names.
  3675 
  3676 c) Permutative equations (e.g. "a + b = b + a")
  3677 Since the change of names also changes the order of terms, permutative
  3678 rewrite rules may get applied in a different order. Experience shows
  3679 that this is rarely the case (only two adaptions in the whole Isabelle
  3680 distribution).  INCOMPATIBILITY: rewrite proofs
  3681 
  3682 d) ML code directly refering to constant names
  3683 This in general only affects hand-written proof tactics, simprocs and
  3684 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  3685 Consider using @{const_name} antiquotation.
  3686 
  3687 * New class "default" with associated constant "default".
  3688 
  3689 * Function "sgn" is now overloaded and available on int, real, complex
  3690 (and other numeric types), using class "sgn".  Two possible defs of
  3691 sgn are given as equational assumptions in the classes sgn_if and
  3692 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  3693 INCOMPATIBILITY.
  3694 
  3695 * Locale "partial_order" now unified with class "order" (cf. theory
  3696 Orderings), added parameter "less".  INCOMPATIBILITY.
  3697 
  3698 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  3699 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  3700 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  3701 
  3702 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  3703 changed order of proof goals in instance proofs.
  3704 
  3705 * The transitivity reasoner for partial and linear orders is set up
  3706 for classes "order" and "linorder".  Instances of the reasoner are available
  3707 in all contexts importing or interpreting the corresponding locales.
  3708 Method "order" invokes the reasoner separately; the reasoner
  3709 is also integrated with the Simplifier as a solver.  Diagnostic
  3710 command 'print_orders' shows the available instances of the reasoner
  3711 in the current context.
  3712 
  3713 * Localized monotonicity predicate in theory "Orderings"; integrated
  3714 lemmas max_of_mono and min_of_mono with this predicate.
  3715 INCOMPATIBILITY.
  3716 
  3717 * Formulation of theorem "dense" changed slightly due to integration
  3718 with new class dense_linear_order.
  3719 
  3720 * Uniform lattice theory development in HOL.
  3721 
  3722     constants "meet" and "join" now named "inf" and "sup"
  3723     constant "Meet" now named "Inf"
  3724 
  3725     classes "meet_semilorder" and "join_semilorder" now named
  3726       "lower_semilattice" and "upper_semilattice"
  3727     class "lorder" now named "lattice"
  3728     class "comp_lat" now named "complete_lattice"
  3729 
  3730     Instantiation of lattice classes allows explicit definitions
  3731     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  3732 
  3733   INCOMPATIBILITY.  Theorem renames:
  3734 
  3735     meet_left_le            ~> inf_le1
  3736     meet_right_le           ~> inf_le2
  3737     join_left_le            ~> sup_ge1
  3738     join_right_le           ~> sup_ge2
  3739     meet_join_le            ~> inf_sup_ord
  3740     le_meetI                ~> le_infI
  3741     join_leI                ~> le_supI
  3742     le_meet                 ~> le_inf_iff
  3743     le_join                 ~> ge_sup_conv
  3744     meet_idempotent         ~> inf_idem
  3745     join_idempotent         ~> sup_idem
  3746     meet_comm               ~> inf_commute
  3747     join_comm               ~> sup_commute
  3748     meet_leI1               ~> le_infI1
  3749     meet_leI2               ~> le_infI2
  3750     le_joinI1               ~> le_supI1
  3751     le_joinI2               ~> le_supI2
  3752     meet_assoc              ~> inf_assoc
  3753     join_assoc              ~> sup_assoc
  3754     meet_left_comm          ~> inf_left_commute
  3755     meet_left_idempotent    ~> inf_left_idem
  3756     join_left_comm          ~> sup_left_commute
  3757     join_left_idempotent    ~> sup_left_idem
  3758     meet_aci                ~> inf_aci
  3759     join_aci                ~> sup_aci
  3760     le_def_meet             ~> le_iff_inf
  3761     le_def_join             ~> le_iff_sup
  3762     join_absorp2            ~> sup_absorb2
  3763     join_absorp1            ~> sup_absorb1
  3764     meet_absorp1            ~> inf_absorb1
  3765     meet_absorp2            ~> inf_absorb2
  3766     meet_join_absorp        ~> inf_sup_absorb
  3767     join_meet_absorp        ~> sup_inf_absorb
  3768     distrib_join_le         ~> distrib_sup_le
  3769     distrib_meet_le         ~> distrib_inf_le
  3770 
  3771     add_meet_distrib_left   ~> add_inf_distrib_left
  3772     add_join_distrib_left   ~> add_sup_distrib_left
  3773     is_join_neg_meet        ~> is_join_neg_inf
  3774     is_meet_neg_join        ~> is_meet_neg_sup
  3775     add_meet_distrib_right  ~> add_inf_distrib_right
  3776     add_join_distrib_right  ~> add_sup_distrib_right
  3777     add_meet_join_distribs  ~> add_sup_inf_distribs
  3778     join_eq_neg_meet        ~> sup_eq_neg_inf
  3779     meet_eq_neg_join        ~> inf_eq_neg_sup
  3780     add_eq_meet_join        ~> add_eq_inf_sup
  3781     meet_0_imp_0            ~> inf_0_imp_0
  3782     join_0_imp_0            ~> sup_0_imp_0
  3783     meet_0_eq_0             ~> inf_0_eq_0
  3784     join_0_eq_0             ~> sup_0_eq_0
  3785     neg_meet_eq_join        ~> neg_inf_eq_sup
  3786     neg_join_eq_meet        ~> neg_sup_eq_inf
  3787     join_eq_if              ~> sup_eq_if
  3788 
  3789     mono_meet               ~> mono_inf
  3790     mono_join               ~> mono_sup
  3791     meet_bool_eq            ~> inf_bool_eq
  3792     join_bool_eq            ~> sup_bool_eq
  3793     meet_fun_eq             ~> inf_fun_eq
  3794     join_fun_eq             ~> sup_fun_eq
  3795     meet_set_eq             ~> inf_set_eq
  3796     join_set_eq             ~> sup_set_eq
  3797     meet1_iff               ~> inf1_iff
  3798     meet2_iff               ~> inf2_iff
  3799     meet1I                  ~> inf1I
  3800     meet2I                  ~> inf2I
  3801     meet1D1                 ~> inf1D1
  3802     meet2D1                 ~> inf2D1
  3803     meet1D2                 ~> inf1D2
  3804     meet2D2                 ~> inf2D2
  3805     meet1E                  ~> inf1E
  3806     meet2E                  ~> inf2E
  3807     join1_iff               ~> sup1_iff
  3808     join2_iff               ~> sup2_iff
  3809     join1I1                 ~> sup1I1
  3810     join2I1                 ~> sup2I1
  3811     join1I1                 ~> sup1I1
  3812     join2I2                 ~> sup1I2
  3813     join1CI                 ~> sup1CI
  3814     join2CI                 ~> sup2CI
  3815     join1E                  ~> sup1E
  3816     join2E                  ~> sup2E
  3817 
  3818     is_meet_Meet            ~> is_meet_Inf
  3819     Meet_bool_def           ~> Inf_bool_def
  3820     Meet_fun_def            ~> Inf_fun_def
  3821     Meet_greatest           ~> Inf_greatest
  3822     Meet_lower              ~> Inf_lower
  3823     Meet_set_def            ~> Inf_set_def
  3824 
  3825     Sup_def                 ~> Sup_Inf
  3826     Sup_bool_eq             ~> Sup_bool_def
  3827     Sup_fun_eq              ~> Sup_fun_def
  3828     Sup_set_eq              ~> Sup_set_def
  3829 
  3830     listsp_meetI            ~> listsp_infI
  3831     listsp_meet_eq          ~> listsp_inf_eq
  3832 
  3833     meet_min                ~> inf_min
  3834     join_max                ~> sup_max
  3835 
  3836 * Added syntactic class "size"; overloaded constant "size" now has
  3837 type "'a::size ==> bool"
  3838 
  3839 * Internal reorganisation of `size' of datatypes: size theorems
  3840 "foo.size" are no longer subsumed by "foo.simps" (but are still
  3841 simplification rules by default!); theorems "prod.size" now named
  3842 "*.size".
  3843 
  3844 * Class "div" now inherits from class "times" rather than "type".
  3845 INCOMPATIBILITY.
  3846 
  3847 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  3848 Linorder etc.  have disappeared; operations defined in terms of
  3849 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  3850 
  3851 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  3852 
  3853 * HOL-Word: New extensive library and type for generic, fixed size
  3854 machine words, with arithemtic, bit-wise, shifting and rotating
  3855 operations, reflection into int, nat, and bool lists, automation for
  3856 linear arithmetic (by automatic reflection into nat or int), including
  3857 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  3858 arithmetic type classes, supporting automatic simplification of
  3859 numerals on all operations.
  3860 
  3861 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  3862 
  3863 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  3864 
  3865 * Code generator library theories:
  3866   - Code_Integer represents HOL integers by big integer literals in target
  3867     languages.
  3868   - Code_Char represents HOL characters by character literals in target
  3869     languages.
  3870   - Code_Char_chr like Code_Char, but also offers treatment of character
  3871     codes; includes Code_Integer.
  3872   - Executable_Set allows to generate code for finite sets using lists.
  3873   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  3874     denominator).
  3875   - Executable_Real implements a subset of real numbers, namly those
  3876     representable by rational numbers.
  3877   - Efficient_Nat implements natural numbers by integers, which in general will
  3878     result in higher efficency; pattern matching with 0/Suc is eliminated;
  3879     includes Code_Integer.
  3880   - Code_Index provides an additional datatype index which is mapped to
  3881     target-language built-in integers.
  3882   - Code_Message provides an additional datatype message_string which is isomorphic to
  3883     strings; messages are mapped to target-language strings.
  3884 
  3885 * New package for inductive predicates
  3886 
  3887   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  3888 
  3889     inductive
  3890       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3891       for z_1 :: U_1 and ... and z_n :: U_m
  3892     where
  3893       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3894     | ...
  3895 
  3896   with full support for type-inference, rather than
  3897 
  3898     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3899 
  3900     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3901     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3902 
  3903     inductive "s z_1 ... z_m"
  3904     intros
  3905       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3906       ...
  3907 
  3908   For backward compatibility, there is a wrapper allowing inductive
  3909   sets to be defined with the new package via
  3910 
  3911     inductive_set
  3912       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3913       for z_1 :: U_1 and ... and z_n :: U_m
  3914     where
  3915       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  3916     | ...
  3917 
  3918   or
  3919 
  3920     inductive_set
  3921       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  3922       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  3923       for z_1 :: U_1 and ... and z_n :: U_m
  3924     where
  3925       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  3926     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  3927     | ...
  3928 
  3929   if the additional syntax "p ..." is required.
  3930 
  3931   Numerous examples can be found in the subdirectories src/HOL/Auth,
  3932   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  3933 
  3934   INCOMPATIBILITIES:
  3935 
  3936   - Since declaration and definition of inductive sets or predicates
  3937     is no longer separated, abbreviations involving the newly
  3938     introduced sets or predicates must be specified together with the
  3939     introduction rules after the 'where' keyword (see above), rather
  3940     than before the actual inductive definition.
  3941 
  3942   - The variables in induction and elimination rules are now
  3943     quantified in the order of their occurrence in the introduction
  3944     rules, rather than in alphabetical order. Since this may break
  3945     some proofs, these proofs either have to be repaired, e.g. by
  3946     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  3947     statements of the form
  3948 
  3949       case (rule_i a_i_1 ... a_i_{k_i})
  3950 
  3951     or the old order of quantification has to be restored by explicitly adding
  3952     meta-level quantifiers in the introduction rules, i.e.
  3953 
  3954       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  3955 
  3956   - The format of the elimination rules is now
  3957 
  3958       p z_1 ... z_m x_1 ... x_n ==>
  3959         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  3960         ==> ... ==> P
  3961 
  3962     for predicates and
  3963 
  3964       (x_1, ..., x_n) : s z_1 ... z_m ==>
  3965         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  3966         ==> ... ==> P
  3967 
  3968     for sets rather than
  3969 
  3970       x : s z_1 ... z_m ==>
  3971         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  3972         ==> ... ==> P
  3973 
  3974     This may require terms in goals to be expanded to n-tuples
  3975     (e.g. using case_tac or simplification with the split_paired_all
  3976     rule) before the above elimination rule is applicable.
  3977 
  3978   - The elimination or case analysis rules for (mutually) inductive
  3979     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  3980     list of rules "p_1_..._p_k.elims" is no longer available.
  3981 
  3982 * New package "function"/"fun" for general recursive functions,
  3983 supporting mutual and nested recursion, definitions in local contexts,
  3984 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  3985 for small examples, and the separate tutorial on the function
  3986 package. The old recdef "package" is still available as before, but
  3987 users are encouraged to use the new package.
  3988 
  3989 * Method "lexicographic_order" automatically synthesizes termination
  3990 relations as lexicographic combinations of size measures. 
  3991 
  3992 * Case-expressions allow arbitrary constructor-patterns (including
  3993 "_") and take their order into account, like in functional
  3994 programming.  Internally, this is translated into nested
  3995 case-expressions; missing cases are added and mapped to the predefined
  3996 constant "undefined". In complicated cases printing may no longer show
  3997 the original input but the internal form. Lambda-abstractions allow
  3998 the same form of pattern matching: "% pat1 => e1 | ..." is an
  3999 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  4000 variable.
  4001 
  4002 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  4003 is an abbreviation for "of_nat :: nat => int". The simplification
  4004 rules for "of_nat" have been changed to work like "int" did
  4005 previously.  Potential INCOMPATIBILITY:
  4006   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  4007   - of_nat_diff and of_nat_mult are no longer default simp rules
  4008 
  4009 * Method "algebra" solves polynomial equations over (semi)rings using
  4010 Groebner bases. The (semi)ring structure is defined by locales and the
  4011 tool setup depends on that generic context. Installing the method for
  4012 a specific type involves instantiating the locale and possibly adding
  4013 declarations for computation on the coefficients.  The method is
  4014 already instantiated for natural numbers and for the axiomatic class
  4015 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  4016 CALCULEMUS 2007 for the general principles underlying this
  4017 architecture of context-aware proof-tools.
  4018 
  4019 * Method "ferrack" implements quantifier elimination over
  4020 special-purpose dense linear orders using locales (analogous to
  4021 "algebra"). The method is already installed for class
  4022 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  4023 rat, etc.
  4024 
  4025 * Former constant "List.op @" now named "List.append".  Use ML
  4026 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  4027 circumvent possible incompatibilities when working on ML level.
  4028 
  4029 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  4030 
  4031 * New function listsum :: 'a list => 'a for arbitrary monoids.
  4032 Special syntax: "SUM x <- xs. f x" (and latex variants)
  4033 
  4034 * New syntax for Haskell-like list comprehension (input only), eg.
  4035 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  4036 
  4037 * The special syntax for function "filter" has changed from [x :
  4038 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  4039 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  4040 
  4041 * [a..b] is now defined for arbitrary linear orders.  It used to be
  4042 defined on nat only, as an abbreviation for [a..<Suc b]
  4043 INCOMPATIBILITY.
  4044 
  4045 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  4046 
  4047 * New functions "sorted" and "sort" in src/HOL/List.thy.
  4048 
  4049 * New lemma collection field_simps (an extension of ring_simps) for
  4050 manipulating (in)equations involving division. Multiplies with all
  4051 denominators that can be proved to be non-zero (in equations) or
  4052 positive/negative (in inequations).
  4053 
  4054 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  4055 have been improved and renamed to ring_simps, group_simps and
  4056 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  4057 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  4058 
  4059 * Theory Library/Commutative_Ring: switched from recdef to function
  4060 package; constants add, mul, pow now curried.  Infix syntax for
  4061 algebraic operations.
  4062 
  4063 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  4064 INCOMPATIBILITY.
  4065 
  4066 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  4067 INCOMPATIBILITY.
  4068 
  4069 * HOL/records: generalised field-update to take a function on the
  4070 field rather than the new value: r(|A := x|) is translated to A_update
  4071 (K x) r The K-combinator that is internally used is called K_record.
  4072 INCOMPATIBILITY: Usage of the plain update functions has to be
  4073 adapted.
  4074  
  4075 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  4076 * x = 0, which are required for a semiring.  Richer structures do not
  4077 inherit from semiring_0 anymore, because this property is a theorem
  4078 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  4079 there is more to prove, but this is mostly trivial.
  4080 
  4081 * Class "recpower" is generalized to arbitrary monoids, not just
  4082 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  4083 commutativity or semiring properties additionally.
  4084 
  4085 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  4086 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  4087 better use 'abbreviation'.
  4088 
  4089 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  4090 
  4091 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  4092 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  4093 significant changes for setting up numeral syntax for types:
  4094   - New constants Numeral.pred and Numeral.succ instead
  4095       of former Numeral.bin_pred and Numeral.bin_succ.
  4096   - Use integer operations instead of bin_add, bin_mult and so on.
  4097   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  4098   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  4099 
  4100 See src/HOL/Integ/IntArith.thy for an example setup.
  4101 
  4102 * Command 'normal_form' computes the normal form of a term that may
  4103 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  4104 produces ``[b, c, a]'' (without proof).  This command is suitable for
  4105 heavy-duty computations because the functions are compiled to ML
  4106 first.  Correspondingly, a method "normalization" is provided.  See
  4107 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  4108 
  4109 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  4110 25 like -->); output depends on the "iff" print_mode, the default is
  4111 "A = B" (with priority 50).
  4112 
  4113 * Relations less (<) and less_eq (<=) are also available on type bool.
  4114 Modified syntax to disallow nesting without explicit parentheses,
  4115 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  4116 INCOMPATIBILITY.
  4117 
  4118 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  4119 
  4120 * Relation composition operator "op O" now has precedence 75 and binds
  4121 stronger than union and intersection. INCOMPATIBILITY.
  4122 
  4123 * The old set interval syntax "{m..n(}" (and relatives) has been
  4124 removed.  Use "{m..<n}" (and relatives) instead.
  4125 
  4126 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  4127 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  4128 ``declare [[simproc del: neq]]''.
  4129 
  4130 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  4131 True/False.
  4132 
  4133 * Theorem Cons_eq_map_conv no longer declared as "simp".
  4134 
  4135 * Theorem setsum_mult renamed to setsum_right_distrib.
  4136 
  4137 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  4138 ``rule'' method.
  4139 
  4140 * Reimplemented methods "sat" and "satx", with several improvements:
  4141 goals no longer need to be stated as "<prems> ==> False", equivalences
  4142 (i.e. "=" on type bool) are handled, variable names of the form
  4143 "lit_<n>" are no longer reserved, significant speedup.
  4144 
  4145 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  4146 zChaff is still supported as well.
  4147 
  4148 * 'inductive' and 'datatype': provide projections of mutual rules,
  4149 bundled as foo_bar.inducts;
  4150 
  4151 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  4152 Library.
  4153 
  4154 * Library: moved theory Accessible_Part to main HOL.
  4155 
  4156 * Library: added theory Coinductive_List of potentially infinite lists
  4157 as greatest fixed-point.
  4158 
  4159 * Library: added theory AssocList which implements (finite) maps as
  4160 association lists.
  4161 
  4162 * Method "evaluation" solves goals (i.e. a boolean expression)
  4163 efficiently by compiling it to ML.  The goal is "proved" (via an
  4164 oracle) if it evaluates to True.
  4165 
  4166 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  4167 also when invoked by the simplifier.  This results in the Simplifier
  4168 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  4169 Configuration option fast_arith_split_limit=0 recovers the old
  4170 behavior.
  4171 
  4172 * Support for hex (0x20) and binary (0b1001) numerals.
  4173 
  4174 * New method: reify eqs (t), where eqs are equations for an
  4175 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  4176 parameter, computes a term s::'b and a list xs::'a list and proves the
  4177 theorem I xs s = t. This is also known as reification or quoting. The
  4178 resulting theorem is applied to the subgoal to substitute t with I xs
  4179 s.  If t is omitted, the subgoal itself is reified.
  4180 
  4181 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  4182 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  4183 where f is supposed to be a computable function (in the sense of code
  4184 generattion). The method uses reify to compute s and xs as above then
  4185 applies corr_thm and uses normalization by evaluation to "prove" f s =
  4186 r and finally gets the theorem t = r, which is again applied to the
  4187 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  4188 
  4189 * Reflection: Automatic reification now handels binding, an example is
  4190 available in src/HOL/ex/ReflectionEx.thy
  4191 
  4192 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  4193 command 'statespace' that is similar to 'record', but introduces an
  4194 abstract specification based on the locale infrastructure instead of
  4195 HOL types.  This leads to extra flexibility in composing state spaces,
  4196 in particular multiple inheritance and renaming of components.
  4197 
  4198 
  4199 *** HOL-Complex ***
  4200 
  4201 * Hyperreal: Functions root and sqrt are now defined on negative real
  4202 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  4203 Nonnegativity side conditions have been removed from many lemmas, so
  4204 that more subgoals may now be solved by simplification; potential
  4205 INCOMPATIBILITY.
  4206 
  4207 * Real: new type classes formalize real normed vector spaces and
  4208 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  4209 and norm :: 'a => real.
  4210 
  4211 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  4212 reals into other types. The overloaded constant Reals :: 'a set is now
  4213 defined as range of_real; potential INCOMPATIBILITY.
  4214 
  4215 * Real: proper support for ML code generation, including 'quickcheck'.
  4216 Reals are implemented as arbitrary precision rationals.
  4217 
  4218 * Hyperreal: Several constants that previously worked only for the
  4219 reals have been generalized, so they now work over arbitrary vector
  4220 spaces. Type annotations may need to be added in some cases; potential
  4221 INCOMPATIBILITY.
  4222 
  4223   Infinitesimal  :: ('a::real_normed_vector) star set
  4224   HFinite        :: ('a::real_normed_vector) star set
  4225   HInfinite      :: ('a::real_normed_vector) star set
  4226   approx         :: ('a::real_normed_vector) star => 'a star => bool
  4227   monad          :: ('a::real_normed_vector) star => 'a star set
  4228   galaxy         :: ('a::real_normed_vector) star => 'a star set
  4229   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  4230   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  4231   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  4232   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  4233   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  4234   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  4235   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  4236   sgn            :: 'a::real_normed_vector => 'a
  4237   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  4238 
  4239 * Complex: Some complex-specific constants are now abbreviations for
  4240 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  4241 hnorm.  Other constants have been entirely removed in favor of the
  4242 polymorphic versions (INCOMPATIBILITY):
  4243 
  4244   approx        <-- capprox
  4245   HFinite       <-- CFinite
  4246   HInfinite     <-- CInfinite
  4247   Infinitesimal <-- CInfinitesimal
  4248   monad         <-- cmonad
  4249   galaxy        <-- cgalaxy
  4250   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  4251   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  4252   (ns)deriv     <-- (ns)cderiv
  4253 
  4254 
  4255 *** HOL-Algebra ***
  4256 
  4257 * Formalisation of ideals and the quotient construction over rings.
  4258 
  4259 * Order and lattice theory no longer based on records.
  4260 INCOMPATIBILITY.
  4261 
  4262 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  4263 greatest_closed.  INCOMPATIBILITY.
  4264 
  4265 * Method algebra is now set up via an attribute.  For examples see
  4266 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  4267 of algebraic structures.
  4268 
  4269 * Renamed theory CRing to Ring.
  4270 
  4271 
  4272 *** HOL-Nominal ***
  4273 
  4274 * Substantial, yet incomplete support for nominal datatypes (binding
  4275 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  4276 src/HOL/Nominal/Examples.  Prospective users should consult
  4277 http://isabelle.in.tum.de/nominal/
  4278 
  4279 
  4280 *** ML ***
  4281 
  4282 * ML basics: just one true type int, which coincides with IntInf.int
  4283 (even on SML/NJ).
  4284 
  4285 * ML within Isar: antiquotations allow to embed statically-checked
  4286 formal entities in the source, referring to the context available at
  4287 compile-time.  For example:
  4288 
  4289 ML {* @{sort "{zero,one}"} *}
  4290 ML {* @{typ "'a => 'b"} *}
  4291 ML {* @{term "%x. x"} *}
  4292 ML {* @{prop "x == y"} *}
  4293 ML {* @{ctyp "'a => 'b"} *}
  4294 ML {* @{cterm "%x. x"} *}
  4295 ML {* @{cprop "x == y"} *}
  4296 ML {* @{thm asm_rl} *}
  4297 ML {* @{thms asm_rl} *}
  4298 ML {* @{type_name c} *}
  4299 ML {* @{type_syntax c} *}
  4300 ML {* @{const_name c} *}
  4301 ML {* @{const_syntax c} *}
  4302 ML {* @{context} *}
  4303 ML {* @{theory} *}
  4304 ML {* @{theory Pure} *}
  4305 ML {* @{theory_ref} *}
  4306 ML {* @{theory_ref Pure} *}
  4307 ML {* @{simpset} *}
  4308 ML {* @{claset} *}
  4309 ML {* @{clasimpset} *}
  4310 
  4311 The same works for sources being ``used'' within an Isar context.
  4312 
  4313 * ML in Isar: improved error reporting; extra verbosity with
  4314 ML_Context.trace enabled.
  4315 
  4316 * Pure/General/table.ML: the join operations now works via exceptions
  4317 DUP/SAME instead of type option. This is simpler in simple cases, and
  4318 admits slightly more efficient complex applications.
  4319 
  4320 * Pure: 'advanced' translation functions (parse_translation etc.) now
  4321 use Context.generic instead of just theory.
  4322 
  4323 * Pure: datatype Context.generic joins theory/Proof.context and
  4324 provides some facilities for code that works in either kind of
  4325 context, notably GenericDataFun for uniform theory and proof data.
  4326 
  4327 * Pure: simplified internal attribute type, which is now always
  4328 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  4329 local (Proof.context) attributes have been discontinued, while
  4330 minimizing code duplication. Thm.rule_attribute and
  4331 Thm.declaration_attribute build canonical attributes; see also structure
  4332 Context for further operations on Context.generic, notably
  4333 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  4334 declarations and definitions.
  4335 
  4336 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  4337 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  4338 init only required for impure data. INCOMPATIBILITY: empty really need
  4339 to be empty (no dependencies on theory content!)
  4340 
  4341 * Pure/kernel: consts certification ignores sort constraints given in
  4342 signature declarations. (This information is not relevant to the
  4343 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  4344 potential INCOMPATIBILITY.
  4345 
  4346 * Pure: axiomatic type classes are now purely definitional, with
  4347 explicit proofs of class axioms and super class relations performed
  4348 internally. See Pure/axclass.ML for the main internal interfaces --
  4349 notably AxClass.define_class supercedes AxClass.add_axclass, and
  4350 AxClass.axiomatize_class/classrel/arity supersede
  4351 Sign.add_classes/classrel/arities.
  4352 
  4353 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  4354 global/local versions on theory vs. Proof.context have been
  4355 discontinued; Attrib.syntax and Method.syntax have been adapted
  4356 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  4357 attributes, methods, etc.
  4358 
  4359 * Pure: several functions of signature "... -> theory -> theory * ..."
  4360 have been reoriented to "... -> theory -> ... * theory" in order to
  4361 allow natural usage in combination with the ||>, ||>>, |-> and
  4362 fold_map combinators.
  4363 
  4364 * Pure: official theorem names (closed derivations) and additional
  4365 comments (tags) are now strictly separate.  Name hints -- which are
  4366 maintained as tags -- may be attached any time without affecting the
  4367 derivation.
  4368 
  4369 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  4370 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  4371 achieve the old behaviour.
  4372 
  4373 * Pure: the "Goal" constant is now called "prop", supporting a
  4374 slightly more general idea of ``protecting'' meta-level rule
  4375 statements.
  4376 
  4377 * Pure: Logic.(un)varify only works in a global context, which is now
  4378 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  4379 Logic.legacy_(un)varify as temporary workaround.
  4380 
  4381 * Pure: structure Name provides scalable operations for generating
  4382 internal variable names, notably Name.variants etc.  This replaces
  4383 some popular functions from term.ML:
  4384 
  4385   Term.variant		->  Name.variant
  4386   Term.variantlist	->  Name.variant_list
  4387   Term.invent_names	->  Name.invent_list
  4388 
  4389 Note that low-level renaming rarely occurs in new code -- operations
  4390 from structure Variable are used instead (see below).
  4391 
  4392 * Pure: structure Variable provides fundamental operations for proper
  4393 treatment of fixed/schematic variables in a context.  For example,
  4394 Variable.import introduces fixes for schematics of given facts and
  4395 Variable.export reverses the effect (up to renaming) -- this replaces
  4396 various freeze_thaw operations.
  4397 
  4398 * Pure: structure Goal provides simple interfaces for
  4399 init/conclude/finish and tactical prove operations (replacing former
  4400 Tactic.prove).  Goal.prove is the canonical way to prove results
  4401 within a given context; Goal.prove_global is a degraded version for
  4402 theory level goals, including a global Drule.standard.  Note that
  4403 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  4404 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  4405 in a locale context).
  4406 
  4407 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  4408 and type checking (Syntax.check_term etc.), with common combinations
  4409 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  4410 which are considered legacy and await removal.
  4411 
  4412 * Pure/Syntax: generic interfaces for type unchecking
  4413 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  4414 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  4415 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  4416 available for convenience, but refer to the very same operations using
  4417 a mere theory instead of a full context.
  4418 
  4419 * Isar: simplified treatment of user-level errors, using exception
  4420 ERROR of string uniformly.  Function error now merely raises ERROR,
  4421 without any side effect on output channels.  The Isar toplevel takes
  4422 care of proper display of ERROR exceptions.  ML code may use plain
  4423 handle/can/try; cat_error may be used to concatenate errors like this:
  4424 
  4425   ... handle ERROR msg => cat_error msg "..."
  4426 
  4427 Toplevel ML code (run directly or through the Isar toplevel) may be
  4428 embedded into the Isar toplevel with exception display/debug like
  4429 this:
  4430 
  4431   Isar.toplevel (fn () => ...)
  4432 
  4433 INCOMPATIBILITY, removed special transform_error facilities, removed
  4434 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  4435 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  4436 -- use plain ERROR instead.
  4437 
  4438 * Isar: theory setup now has type (theory -> theory), instead of a
  4439 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  4440 
  4441 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  4442 ProofContext.debug/verbose flags.
  4443 
  4444 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  4445 theory before entering a proof state.  Transactions now always see a
  4446 quasi-functional intermediate checkpoint, both in interactive and
  4447 batch mode.
  4448 
  4449 * Isar: simplified interfaces for outer syntax.  Renamed
  4450 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  4451 OuterSyntax.add_parsers -- this functionality is now included in
  4452 OuterSyntax.command etc.  INCOMPATIBILITY.
  4453 
  4454 * Simplifier: the simpset of a running simplification process now
  4455 contains a proof context (cf. Simplifier.the_context), which is the
  4456 very context that the initial simpset has been retrieved from (by
  4457 simpset_of/local_simpset_of).  Consequently, all plug-in components
  4458 (solver, looper etc.) may depend on arbitrary proof data.
  4459 
  4460 * Simplifier.inherit_context inherits the proof context (plus the
  4461 local bounds) of the current simplification process; any simproc
  4462 etc. that calls the Simplifier recursively should do this!  Removed
  4463 former Simplifier.inherit_bounds, which is already included here --
  4464 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  4465 specify an explicit context using Simplifier.context/theory_context.
  4466 
  4467 * Simplifier/Classical Reasoner: more abstract interfaces
  4468 change_simpset/claset for modifying the simpset/claset reference of a
  4469 theory; raw versions simpset/claset_ref etc. have been discontinued --
  4470 INCOMPATIBILITY.
  4471 
  4472 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  4473 "Trueprop" etc.
  4474 
  4475 
  4476 *** System ***
  4477 
  4478 * settings: the default heap location within ISABELLE_HOME_USER now
  4479 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  4480 Isabelle installations.
  4481 
  4482 * isabelle-process: option -S (secure mode) disables some critical
  4483 operations, notably runtime compilation and evaluation of ML source
  4484 code.
  4485 
  4486 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  4487 
  4488 * Support for parallel execution, using native multicore support of
  4489 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  4490 independent theories, according to the given theory header
  4491 specifications. The maximum number of worker threads is specified via
  4492 usedir option -M or the "max-threads" setting in Proof General. A
  4493 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  4494 to 6 on a 8-core machine.  User-code needs to observe certain
  4495 guidelines for thread-safe programming, see appendix A in the Isar
  4496 Implementation manual.
  4497 
  4498 
  4499 
  4500 New in Isabelle2005 (October 2005)
  4501 ----------------------------------
  4502 
  4503 *** General ***
  4504 
  4505 * Theory headers: the new header syntax for Isar theories is
  4506 
  4507   theory <name>
  4508   imports <theory1> ... <theoryN>
  4509   uses <file1> ... <fileM>
  4510   begin
  4511 
  4512 where the 'uses' part is optional.  The previous syntax
  4513 
  4514   theory <name> = <theory1> + ... + <theoryN>:
  4515 
  4516 will disappear in the next release.  Use isatool fixheaders to convert
  4517 existing theory files.  Note that there is no change in ancient
  4518 non-Isar theories now, but these will disappear soon.
  4519 
  4520 * Theory loader: parent theories can now also be referred to via
  4521 relative and absolute paths.
  4522 
  4523 * Command 'find_theorems' searches for a list of criteria instead of a
  4524 list of constants. Known criteria are: intro, elim, dest, name:string,
  4525 simp:term, and any term. Criteria can be preceded by '-' to select
  4526 theorems that do not match. Intro, elim, dest select theorems that
  4527 match the current goal, name:s selects theorems whose fully qualified
  4528 name contain s, and simp:term selects all simplification rules whose
  4529 lhs match term.  Any other term is interpreted as pattern and selects
  4530 all theorems matching the pattern. Available in ProofGeneral under
  4531 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  4532 
  4533   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  4534 
  4535 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  4536 matching the current goal as introduction rule and not having "HOL."
  4537 in their name (i.e. not being defined in theory HOL).
  4538 
  4539 * Command 'thms_containing' has been discontinued in favour of
  4540 'find_theorems'; INCOMPATIBILITY.
  4541 
  4542 * Communication with Proof General is now 8bit clean, which means that
  4543 Unicode text in UTF-8 encoding may be used within theory texts (both
  4544 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4545 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4546 
  4547   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4548   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4549 
  4550 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4551 Classical Reasoner.  Typical big applications run around 2 times
  4552 faster.
  4553 
  4554 
  4555 *** Document preparation ***
  4556 
  4557 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4558 of raw sources.  Only those symbols that do not require additional
  4559 LaTeX packages (depending on comments in isabellesym.sty) are
  4560 displayed properly, everything else is left verbatim.  isatool display
  4561 and isatool print are used as front ends (these are subject to the
  4562 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4563 
  4564 * Command tags control specific markup of certain regions of text,
  4565 notably folding and hiding.  Predefined tags include "theory" (for
  4566 theory begin and end), "proof" for proof commands, and "ML" for
  4567 commands involving ML code; the additional tags "visible" and
  4568 "invisible" are unused by default.  Users may give explicit tag
  4569 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4570 interpretation of tags is determined by the LaTeX job during document
  4571 preparation: see option -V of isatool usedir, or options -n and -t of
  4572 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4573 \isadroptag.
  4574 
  4575 Several document versions may be produced at the same time via isatool
  4576 usedir (the generated index.html will link all of them).  Typical
  4577 specifications include ''-V document=theory,proof,ML'' to present
  4578 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4579 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4580 these parts without any formal replacement text.  The Isabelle site
  4581 default settings produce ''document'' and ''outline'' versions as
  4582 specified above.
  4583 
  4584 * Several new antiquotations:
  4585 
  4586   @{term_type term} prints a term with its type annotated;
  4587 
  4588   @{typeof term} prints the type of a term;
  4589 
  4590   @{const const} is the same as @{term const}, but checks that the
  4591   argument is a known logical constant;
  4592 
  4593   @{term_style style term} and @{thm_style style thm} print a term or
  4594   theorem applying a "style" to it
  4595 
  4596   @{ML text}
  4597 
  4598 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4599 definitions, equations, inequations etc., 'concl' printing only the
  4600 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4601 to print the specified premise.  TermStyle.add_style provides an ML
  4602 interface for introducing further styles.  See also the "LaTeX Sugar"
  4603 document practical applications.  The ML antiquotation prints
  4604 type-checked ML expressions verbatim.
  4605 
  4606 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4607 and 'text' support optional locale specification '(in loc)', which
  4608 specifies the default context for interpreting antiquotations.  For
  4609 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4610 
  4611 * Option 'locale=NAME' of antiquotations specifies an alternative
  4612 context interpreting the subsequent argument.  For example: @{thm
  4613 [locale=lattice] inf_assoc}.
  4614 
  4615 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4616 a proof context.
  4617 
  4618 * Proper output of antiquotations for theory commands involving a
  4619 proof context (such as 'locale' or 'theorem (in loc) ...').
  4620 
  4621 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4622 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4623 
  4624 * isatool usedir: new option -C (default true) controls whether option
  4625 -D should include a copy of the original document directory; -C false
  4626 prevents unwanted effects such as copying of administrative CVS data.
  4627 
  4628 
  4629 *** Pure ***
  4630 
  4631 * Considerably improved version of 'constdefs' command.  Now performs
  4632 automatic type-inference of declared constants; additional support for
  4633 local structure declarations (cf. locales and HOL records), see also
  4634 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4635 sequential dependencies of definitions within a single 'constdefs'
  4636 section; moreover, the declared name needs to be an identifier.  If
  4637 all fails, consider to fall back on 'consts' and 'defs' separately.
  4638 
  4639 * Improved indexed syntax and implicit structures.  First of all,
  4640 indexed syntax provides a notational device for subscripted
  4641 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4642 expressions.  Secondly, in a local context with structure
  4643 declarations, number indexes \<^sub>n or the empty index (default
  4644 number 1) refer to a certain fixed variable implicitly; option
  4645 show_structs controls printing of implicit structures.  Typical
  4646 applications of these concepts involve record types and locales.
  4647 
  4648 * New command 'no_syntax' removes grammar declarations (and
  4649 translations) resulting from the given syntax specification, which is
  4650 interpreted in the same manner as for the 'syntax' command.
  4651 
  4652 * 'Advanced' translation functions (parse_translation etc.) may depend
  4653 on the signature of the theory context being presently used for
  4654 parsing/printing, see also isar-ref manual.
  4655 
  4656 * Improved 'oracle' command provides a type-safe interface to turn an
  4657 ML expression of type theory -> T -> term into a primitive rule of
  4658 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4659 is already included here); see also FOL/ex/IffExample.thy;
  4660 INCOMPATIBILITY.
  4661 
  4662 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4663 before); "cI" is no longer bound, use "c.intro" instead.
  4664 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4665 axclasses vs. locales.
  4666 
  4667 * Improved internal renaming of symbolic identifiers -- attach primes
  4668 instead of base 26 numbers.
  4669 
  4670 * New flag show_question_marks controls printing of leading question
  4671 marks in schematic variable names.
  4672 
  4673 * In schematic variable names, *any* symbol following \<^isub> or
  4674 \<^isup> is now treated as part of the base name.  For example, the
  4675 following works without printing of awkward ".0" indexes:
  4676 
  4677   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  4678     by simp
  4679 
  4680 * Inner syntax includes (*(*nested*) comments*).
  4681 
  4682 * Pretty printer now supports unbreakable blocks, specified in mixfix
  4683 annotations as "(00...)".
  4684 
  4685 * Clear separation of logical types and nonterminals, where the latter
  4686 may only occur in 'syntax' specifications or type abbreviations.
  4687 Before that distinction was only partially implemented via type class
  4688 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  4689 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  4690 exotic syntax specifications may require further adaption
  4691 (e.g. Cube/Cube.thy).
  4692 
  4693 * Removed obsolete type class "logic", use the top sort {} instead.
  4694 Note that non-logical types should be declared as 'nonterminals'
  4695 rather than 'types'.  INCOMPATIBILITY for new object-logic
  4696 specifications.
  4697 
  4698 * Attributes 'induct' and 'cases': type or set names may now be
  4699 locally fixed variables as well.
  4700 
  4701 * Simplifier: can now control the depth to which conditional rewriting
  4702 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  4703 Limit.
  4704 
  4705 * Simplifier: simplification procedures may now take the current
  4706 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  4707 interface), which is very useful for calling the Simplifier
  4708 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  4709 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  4710 low-level mk_simproc no longer applies Logic.varify internally, to
  4711 allow for use in a context of fixed variables.
  4712 
  4713 * thin_tac now works even if the assumption being deleted contains !!
  4714 or ==>.  More generally, erule now works even if the major premise of
  4715 the elimination rule contains !! or ==>.
  4716 
  4717 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  4718 
  4719 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  4720 from Pure, which contains all common declarations already.  Both
  4721 theories are defined via plain Isabelle/Isar .thy files.
  4722 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  4723 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  4724 use isatool fixcpure to adapt your theory and ML sources.
  4725 
  4726 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  4727 selections of theorems in named facts via index ranges.
  4728 
  4729 * 'print_theorems': in theory mode, really print the difference
  4730 wrt. the last state (works for interactive theory development only),
  4731 in proof mode print all local facts (cf. 'print_facts');
  4732 
  4733 * 'hide': option '(open)' hides only base names.
  4734 
  4735 * More efficient treatment of intermediate checkpoints in interactive
  4736 theory development.
  4737 
  4738 * Code generator is now invoked via code_module (incremental code
  4739 generation) and code_library (modular code generation, ML structures
  4740 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  4741 must be quoted when used as identifiers.
  4742 
  4743 * New 'value' command for reading, evaluating and printing terms using
  4744 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  4745 quoted when used as identifier.
  4746 
  4747 
  4748 *** Locales ***
  4749 
  4750 * New commands for the interpretation of locale expressions in
  4751 theories (1), locales (2) and proof contexts (3).  These generate
  4752 proof obligations from the expression specification.  After the
  4753 obligations have been discharged, theorems of the expression are added
  4754 to the theory, target locale or proof context.  The synopsis of the
  4755 commands is a follows:
  4756 
  4757   (1) interpretation expr inst
  4758   (2) interpretation target < expr
  4759   (3) interpret expr inst
  4760 
  4761 Interpretation in theories and proof contexts require a parameter
  4762 instantiation of terms from the current context.  This is applied to
  4763 specifications and theorems of the interpreted expression.
  4764 Interpretation in locales only permits parameter renaming through the
  4765 locale expression.  Interpretation is smart in that interpretations
  4766 that are active already do not occur in proof obligations, neither are
  4767 instantiated theorems stored in duplicate.  Use 'print_interps' to
  4768 inspect active interpretations of a particular locale.  For details,
  4769 see the Isar Reference manual.  Examples can be found in
  4770 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  4771 
  4772 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  4773 'interpret' instead.
  4774 
  4775 * New context element 'constrains' for adding type constraints to
  4776 parameters.
  4777 
  4778 * Context expressions: renaming of parameters with syntax
  4779 redeclaration.
  4780 
  4781 * Locale declaration: 'includes' disallowed.
  4782 
  4783 * Proper static binding of attribute syntax -- i.e. types / terms /
  4784 facts mentioned as arguments are always those of the locale definition
  4785 context, independently of the context of later invocations.  Moreover,
  4786 locale operations (renaming and type / term instantiation) are applied
  4787 to attribute arguments as expected.
  4788 
  4789 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  4790 actual attributes; rare situations may require Attrib.attribute to
  4791 embed those attributes into Attrib.src that lack concrete syntax.
  4792 Attribute implementations need to cooperate properly with the static
  4793 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  4794 Attrib.XXX_thm etc. already do the right thing without further
  4795 intervention.  Only unusual applications -- such as "where" or "of"
  4796 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  4797 on the context and the facts involved -- may have to assign parsed
  4798 values to argument tokens explicitly.
  4799 
  4800 * Changed parameter management in theorem generation for long goal
  4801 statements with 'includes'.  INCOMPATIBILITY: produces a different
  4802 theorem statement in rare situations.
  4803 
  4804 * Locale inspection command 'print_locale' omits notes elements.  Use
  4805 'print_locale!' to have them included in the output.
  4806 
  4807 
  4808 *** Provers ***
  4809 
  4810 * Provers/hypsubst.ML: improved version of the subst method, for
  4811 single-step rewriting: it now works in bound variable contexts. New is
  4812 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  4813 rewrite a different subterm than the original subst method, which is
  4814 still available as 'simplesubst'.
  4815 
  4816 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  4817 and quasi orders.
  4818 
  4819 * Provers/trancl.ML: new transitivity reasoner for transitive and
  4820 reflexive-transitive closure of relations.
  4821 
  4822 * Provers/blast.ML: new reference depth_limit to make blast's depth
  4823 limit (previously hard-coded with a value of 20) user-definable.
  4824 
  4825 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  4826 is peformed already.  Object-logics merely need to finish their
  4827 initial simpset configuration as before.  INCOMPATIBILITY.
  4828 
  4829 
  4830 *** HOL ***
  4831 
  4832 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  4833 
  4834   syntax (epsilon)
  4835     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  4836 
  4837 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  4838 and x-symbol; use option '-m epsilon' to get it actually printed.
  4839 Moreover, the mathematically important symbolic identifier \<epsilon>
  4840 becomes available as variable, constant etc.  INCOMPATIBILITY,
  4841 
  4842 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  4843 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  4844 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  4845 support corresponding Isar calculations.
  4846 
  4847 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  4848 instead of ":".
  4849 
  4850 * theory SetInterval: changed the syntax for open intervals:
  4851 
  4852   Old       New
  4853   {..n(}    {..<n}
  4854   {)n..}    {n<..}
  4855   {m..n(}   {m..<n}
  4856   {)m..n}   {m<..n}
  4857   {)m..n(}  {m<..<n}
  4858 
  4859 The old syntax is still supported but will disappear in the next
  4860 release.  For conversion use the following Emacs search and replace
  4861 patterns (these are not perfect but work quite well):
  4862 
  4863   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  4864   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  4865 
  4866 * Theory Commutative_Ring (in Library): method comm_ring for proving
  4867 equalities in commutative rings; method 'algebra' provides a generic
  4868 interface.
  4869 
  4870 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  4871 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  4872 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  4873 be a tuple pattern.
  4874 
  4875 Some new syntax forms are available:
  4876 
  4877   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  4878   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  4879   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  4880   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  4881 
  4882 The latter form "\<Sum>x < k. e" used to be based on a separate
  4883 function "Summation", which has been discontinued.
  4884 
  4885 * theory Finite_Set: in structured induction proofs, the insert case
  4886 is now 'case (insert x F)' instead of the old counterintuitive 'case
  4887 (insert F x)'.
  4888 
  4889 * The 'refute' command has been extended to support a much larger
  4890 fragment of HOL, including axiomatic type classes, constdefs and
  4891 typedefs, inductive datatypes and recursion.
  4892 
  4893 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  4894 Requires zChaff with proof generation to be installed.  See
  4895 HOL/ex/SAT_Examples.thy for examples.
  4896 
  4897 * Datatype induction via method 'induct' now preserves the name of the
  4898 induction variable. For example, when proving P(xs::'a list) by
  4899 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  4900 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  4901 in unstructured proof scripts.
  4902 
  4903 * Reworked implementation of records.  Improved scalability for
  4904 records with many fields, avoiding performance problems for type
  4905 inference. Records are no longer composed of nested field types, but
  4906 of nested extension types. Therefore the record type only grows linear
  4907 in the number of extensions and not in the number of fields.  The
  4908 top-level (users) view on records is preserved.  Potential
  4909 INCOMPATIBILITY only in strange cases, where the theory depends on the
  4910 old record representation. The type generated for a record is called
  4911 <record_name>_ext_type.
  4912 
  4913 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  4914 proofs triggered by a record definition or a simproc (if
  4915 quick_and_dirty is enabled).  Definitions of large records can take
  4916 quite long.
  4917 
  4918 New simproc record_upd_simproc for simplification of multiple record
  4919 updates enabled by default.  Moreover, trivial updates are also
  4920 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  4921 occasionally, since simplification is more powerful by default.
  4922 
  4923 * typedef: proper support for polymorphic sets, which contain extra
  4924 type-variables in the term.
  4925 
  4926 * Simplifier: automatically reasons about transitivity chains
  4927 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  4928 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  4929 old proofs break occasionally as simplification may now solve more
  4930 goals than previously.
  4931 
  4932 * Simplifier: converts x <= y into x = y if assumption y <= x is
  4933 present.  Works for all partial orders (class "order"), in particular
  4934 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  4935 just like y <= x.
  4936 
  4937 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  4938 bound variable or a constant then the let is unfolded.  Otherwise
  4939 first a is simplified to b, and then f b is simplified to g. If
  4940 possible we abstract b from g arriving at "let x = b in h x",
  4941 otherwise we unfold the let and arrive at g.  The simproc can be
  4942 enabled/disabled by the reference use_let_simproc.  Potential
  4943 INCOMPATIBILITY since simplification is more powerful by default.
  4944 
  4945 * Classical reasoning: the meson method now accepts theorems as arguments.
  4946 
  4947 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  4948 jobs to provide advice on the provability of subgoals.
  4949 
  4950 * Theory OrderedGroup and Ring_and_Field: various additions and
  4951 improvements to faciliate calculations involving equalities and
  4952 inequalities.
  4953 
  4954 The following theorems have been eliminated or modified
  4955 (INCOMPATIBILITY):
  4956 
  4957   abs_eq             now named abs_of_nonneg
  4958   abs_of_ge_0        now named abs_of_nonneg
  4959   abs_minus_eq       now named abs_of_nonpos
  4960   imp_abs_id         now named abs_of_nonneg
  4961   imp_abs_neg_id     now named abs_of_nonpos
  4962   mult_pos           now named mult_pos_pos
  4963   mult_pos_le        now named mult_nonneg_nonneg
  4964   mult_pos_neg_le    now named mult_nonneg_nonpos
  4965   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  4966   mult_neg           now named mult_neg_neg
  4967   mult_neg_le        now named mult_nonpos_nonpos
  4968 
  4969 * The following lemmas in Ring_and_Field have been added to the simplifier:
  4970      
  4971      zero_le_square
  4972      not_square_less_zero 
  4973 
  4974   The following lemmas have been deleted from Real/RealPow:
  4975   
  4976      realpow_zero_zero
  4977      realpow_two
  4978      realpow_less
  4979      zero_le_power
  4980      realpow_two_le
  4981      abs_realpow_two
  4982      realpow_two_abs     
  4983 
  4984 * Theory Parity: added rules for simplifying exponents.
  4985 
  4986 * Theory List:
  4987 
  4988 The following theorems have been eliminated or modified
  4989 (INCOMPATIBILITY):
  4990 
  4991   list_all_Nil       now named list_all.simps(1)
  4992   list_all_Cons      now named list_all.simps(2)
  4993   list_all_conv      now named list_all_iff
  4994   set_mem_eq         now named mem_iff
  4995 
  4996 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  4997 asymptotic "big O" calculations.  See the notes in BigO.thy.
  4998 
  4999 
  5000 *** HOL-Complex ***
  5001 
  5002 * Theory RealDef: better support for embedding natural numbers and
  5003 integers in the reals.
  5004 
  5005 The following theorems have been eliminated or modified
  5006 (INCOMPATIBILITY):
  5007 
  5008   exp_ge_add_one_self  now requires no hypotheses
  5009   real_of_int_add      reversed direction of equality (use [symmetric])
  5010   real_of_int_minus    reversed direction of equality (use [symmetric])
  5011   real_of_int_diff     reversed direction of equality (use [symmetric])
  5012   real_of_int_mult     reversed direction of equality (use [symmetric])
  5013 
  5014 * Theory RComplete: expanded support for floor and ceiling functions.
  5015 
  5016 * Theory Ln is new, with properties of the natural logarithm
  5017 
  5018 * Hyperreal: There is a new type constructor "star" for making
  5019 nonstandard types.  The old type names are now type synonyms:
  5020 
  5021   hypreal = real star
  5022   hypnat = nat star
  5023   hcomplex = complex star
  5024 
  5025 * Hyperreal: Many groups of similarly-defined constants have been
  5026 replaced by polymorphic versions (INCOMPATIBILITY):
  5027 
  5028   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  5029 
  5030   starset      <-- starsetNat, starsetC
  5031   *s*          <-- *sNat*, *sc*
  5032   starset_n    <-- starsetNat_n, starsetC_n
  5033   *sn*         <-- *sNatn*, *scn*
  5034   InternalSets <-- InternalNatSets, InternalCSets
  5035 
  5036   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  5037   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  5038   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  5039   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  5040   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  5041 
  5042 * Hyperreal: Many type-specific theorems have been removed in favor of
  5043 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  5044 
  5045   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  5046   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  5047   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  5048   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  5049   right_minus <-- hypreal_add_minus
  5050   left_minus <-- {hypreal,hcomplex}_add_minus_left
  5051   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  5052   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  5053   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  5054   mult_1_right <-- hcomplex_mult_one_right
  5055   mult_zero_left <-- hcomplex_mult_zero_left
  5056   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  5057   right_distrib <-- hypnat_add_mult_distrib2
  5058   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  5059   right_inverse <-- hypreal_mult_inverse
  5060   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  5061   order_refl <-- {hypreal,hypnat}_le_refl
  5062   order_trans <-- {hypreal,hypnat}_le_trans
  5063   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  5064   order_less_le <-- {hypreal,hypnat}_less_le
  5065   linorder_linear <-- {hypreal,hypnat}_le_linear
  5066   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  5067   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  5068   add_nonneg_nonneg <-- hypreal_le_add_order
  5069 
  5070 * Hyperreal: Separate theorems having to do with type-specific
  5071 versions of constants have been merged into theorems that apply to the
  5072 new polymorphic constants (INCOMPATIBILITY):
  5073 
  5074   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  5075   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  5076   STAR_Un <-- {STAR,NatStar,STARC}_Un
  5077   STAR_Int <-- {STAR,NatStar,STARC}_Int
  5078   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  5079   STAR_subset <-- {STAR,NatStar,STARC}_subset
  5080   STAR_mem <-- {STAR,NatStar,STARC}_mem
  5081   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  5082   STAR_diff <-- {STAR,STARC}_diff
  5083   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  5084     STARC_hcomplex_of_complex}_image_subset
  5085   starset_n_Un <-- starset{Nat,C}_n_Un
  5086   starset_n_Int <-- starset{Nat,C}_n_Int
  5087   starset_n_Compl <-- starset{Nat,C}_n_Compl
  5088   starset_n_diff <-- starset{Nat,C}_n_diff
  5089   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  5090   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  5091   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  5092   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  5093   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  5094   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  5095   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  5096   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  5097   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  5098   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  5099   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  5100   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  5101   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  5102   starfun_diff <-- starfun{C,RC,CR}_diff
  5103   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  5104   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  5105   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  5106   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  5107   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  5108   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  5109   starfun_Id <-- starfunC_Id
  5110   starfun_approx <-- starfun{Nat,CR}_approx
  5111   starfun_capprox <-- starfun{C,RC}_capprox
  5112   starfun_abs <-- starfunNat_rabs
  5113   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  5114   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  5115   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  5116   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  5117   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  5118   starfun_add_approx <-- starfunCR_add_approx
  5119   starfun_inverse_inverse <-- starfunC_inverse_inverse
  5120   starfun_divide <-- starfun{C,CR,RC}_divide
  5121   starfun_n <-- starfun{Nat,C}_n
  5122   starfun_n_mult <-- starfun{Nat,C}_n_mult
  5123   starfun_n_add <-- starfun{Nat,C}_n_add
  5124   starfun_n_add_minus <-- starfunNat_n_add_minus
  5125   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  5126   starfun_n_minus <-- starfun{Nat,C}_n_minus
  5127   starfun_n_eq <-- starfun{Nat,C}_n_eq
  5128 
  5129   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  5130   star_n_minus <-- {hypreal,hcomplex}_minus
  5131   star_n_diff <-- {hypreal,hcomplex}_diff
  5132   star_n_mult <-- {hypreal,hcomplex}_mult
  5133   star_n_inverse <-- {hypreal,hcomplex}_inverse
  5134   star_n_le <-- {hypreal,hypnat}_le
  5135   star_n_less <-- {hypreal,hypnat}_less
  5136   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  5137   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  5138   star_n_abs <-- hypreal_hrabs
  5139   star_n_divide <-- hcomplex_divide
  5140 
  5141   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  5142   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  5143   star_of_diff <-- hypreal_of_real_diff
  5144   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  5145   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  5146   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  5147   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  5148   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  5149   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  5150   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  5151   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  5152   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  5153   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  5154   star_of_number_of <-- {hypreal,hcomplex}_number_of
  5155   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  5156   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  5157   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  5158   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  5159   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  5160   star_of_power <-- hypreal_of_real_power
  5161   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  5162 
  5163 * Hyperreal: new method "transfer" that implements the transfer
  5164 principle of nonstandard analysis. With a subgoal that mentions
  5165 nonstandard types like "'a star", the command "apply transfer"
  5166 replaces it with an equivalent one that mentions only standard types.
  5167 To be successful, all free variables must have standard types; non-
  5168 standard variables must have explicit universal quantifiers.
  5169 
  5170 * Hyperreal: A theory of Taylor series.
  5171 
  5172 
  5173 *** HOLCF ***
  5174 
  5175 * Discontinued special version of 'constdefs' (which used to support
  5176 continuous functions) in favor of the general Pure one with full
  5177 type-inference.
  5178 
  5179 * New simplification procedure for solving continuity conditions; it
  5180 is much faster on terms with many nested lambda abstractions (cubic
  5181 instead of exponential time).
  5182 
  5183 * New syntax for domain package: selector names are now optional.
  5184 Parentheses should be omitted unless argument is lazy, for example:
  5185 
  5186   domain 'a stream = cons "'a" (lazy "'a stream")
  5187 
  5188 * New command 'fixrec' for defining recursive functions with pattern
  5189 matching; defining multiple functions with mutual recursion is also
  5190 supported.  Patterns may include the constants cpair, spair, up, sinl,
  5191 sinr, or any data constructor defined by the domain package. The given
  5192 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  5193 syntax and examples.
  5194 
  5195 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  5196 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  5197 but the proof obligation additionally includes an admissibility
  5198 requirement. The packages generate instances of class cpo or pcpo,
  5199 with continuity and strictness theorems for Rep and Abs.
  5200 
  5201 * HOLCF: Many theorems have been renamed according to a more standard naming
  5202 scheme (INCOMPATIBILITY):
  5203 
  5204   foo_inject:  "foo$x = foo$y ==> x = y"
  5205   foo_eq:      "(foo$x = foo$y) = (x = y)"
  5206   foo_less:    "(foo$x << foo$y) = (x << y)"
  5207   foo_strict:  "foo$UU = UU"
  5208   foo_defined: "... ==> foo$x ~= UU"
  5209   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  5210 
  5211 
  5212 *** ZF ***
  5213 
  5214 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  5215 including the First Isomorphism Theorem (on quotienting by the kernel
  5216 of a homomorphism).
  5217 
  5218 * ZF/Simplifier: install second copy of type solver that actually
  5219 makes use of TC rules declared to Isar proof contexts (or locales);
  5220 the old version is still required for ML proof scripts.
  5221 
  5222 
  5223 *** Cube ***
  5224 
  5225 * Converted to Isar theory format; use locales instead of axiomatic
  5226 theories.
  5227 
  5228 
  5229 *** ML ***
  5230 
  5231 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  5232 for ||>, ||>>, |>>,
  5233 
  5234 * Pure/library.ML no longer defines its own option datatype, but uses
  5235 that of the SML basis, which has constructors NONE and SOME instead of
  5236 None and Some, as well as exception Option.Option instead of OPTION.
  5237 The functions the, if_none, is_some, is_none have been adapted
  5238 accordingly, while Option.map replaces apsome.
  5239 
  5240 * Pure/library.ML: the exception LIST has been given up in favour of
  5241 the standard exceptions Empty and Subscript, as well as
  5242 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  5243 superceded by the standard hd and tl functions etc.
  5244 
  5245 A number of basic list functions are no longer exported to the ML
  5246 toplevel, as they are variants of predefined functions.  The following
  5247 suggests how one can translate existing code:
  5248 
  5249     rev_append xs ys = List.revAppend (xs, ys)
  5250     nth_elem (i, xs) = List.nth (xs, i)
  5251     last_elem xs = List.last xs
  5252     flat xss = List.concat xss
  5253     seq fs = List.app fs
  5254     partition P xs = List.partition P xs
  5255     mapfilter f xs = List.mapPartial f xs
  5256 
  5257 * Pure/library.ML: several combinators for linear functional
  5258 transformations, notably reverse application and composition:
  5259 
  5260   x |> f                f #> g
  5261   (x, y) |-> f          f #-> g
  5262 
  5263 * Pure/library.ML: introduced/changed precedence of infix operators:
  5264 
  5265   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  5266   infix 2 ?;
  5267   infix 3 o oo ooo oooo;
  5268   infix 4 ~~ upto downto;
  5269 
  5270 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  5271 infix operators.
  5272 
  5273 * Pure/library.ML: natural list combinators fold, fold_rev, and
  5274 fold_map support linear functional transformations and nesting.  For
  5275 example:
  5276 
  5277   fold f [x1, ..., xN] y =
  5278     y |> f x1 |> ... |> f xN
  5279 
  5280   (fold o fold) f [xs1, ..., xsN] y =
  5281     y |> fold f xs1 |> ... |> fold f xsN
  5282 
  5283   fold f [x1, ..., xN] =
  5284     f x1 #> ... #> f xN
  5285 
  5286   (fold o fold) f [xs1, ..., xsN] =
  5287     fold f xs1 #> ... #> fold f xsN
  5288 
  5289 * Pure/library.ML: the following selectors on type 'a option are
  5290 available:
  5291 
  5292   the:               'a option -> 'a  (*partial*)
  5293   these:             'a option -> 'a  where 'a = 'b list
  5294   the_default: 'a -> 'a option -> 'a
  5295   the_list:          'a option -> 'a list
  5296 
  5297 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5298 basic operations for association lists, following natural argument
  5299 order; moreover the explicit equality predicate passed here avoids
  5300 potentially expensive polymorphic runtime equality checks.
  5301 The old functions may be expressed as follows:
  5302 
  5303   assoc = uncurry (AList.lookup (op =))
  5304   assocs = these oo AList.lookup (op =)
  5305   overwrite = uncurry (AList.update (op =)) o swap
  5306 
  5307 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5308 
  5309   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  5310   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  5311 
  5312 replacing make_keylist and keyfilter (occassionally used)
  5313 Naive rewrites:
  5314 
  5315   make_keylist = AList.make
  5316   keyfilter = AList.find (op =)
  5317 
  5318 * eq_fst and eq_snd now take explicit equality parameter, thus
  5319   avoiding eqtypes. Naive rewrites:
  5320 
  5321     eq_fst = eq_fst (op =)
  5322     eq_snd = eq_snd (op =)
  5323 
  5324 * Removed deprecated apl and apr (rarely used).
  5325   Naive rewrites:
  5326 
  5327     apl (n, op) =>>= curry op n
  5328     apr (op, m) =>>= fn n => op (n, m)
  5329 
  5330 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  5331 provides a reasonably efficient light-weight implementation of sets as
  5332 lists.
  5333 
  5334 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  5335 few new operations; existing lookup and update are now curried to
  5336 follow natural argument order (for use with fold etc.);
  5337 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  5338 
  5339 * Pure/General: output via the Isabelle channels of
  5340 writeln/warning/error etc. is now passed through Output.output, with a
  5341 hook for arbitrary transformations depending on the print_mode
  5342 (cf. Output.add_mode -- the first active mode that provides a output
  5343 function wins).  Already formatted output may be embedded into further
  5344 text via Output.raw; the result of Pretty.string_of/str_of and derived
  5345 functions (string_of_term/cterm/thm etc.) is already marked raw to
  5346 accommodate easy composition of diagnostic messages etc.  Programmers
  5347 rarely need to care about Output.output or Output.raw at all, with
  5348 some notable exceptions: Output.output is required when bypassing the
  5349 standard channels (writeln etc.), or in token translations to produce
  5350 properly formatted results; Output.raw is required when capturing
  5351 already output material that will eventually be presented to the user
  5352 a second time.  For the default print mode, both Output.output and
  5353 Output.raw have no effect.
  5354 
  5355 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  5356 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  5357 cumulative results are displayed at the end of a batch session.
  5358 
  5359 * Pure/General: File.sysify_path and File.quote_sysify path have been
  5360 replaced by File.platform_path and File.shell_path (with appropriate
  5361 hooks).  This provides a clean interface for unusual systems where the
  5362 internal and external process view of file names are different.
  5363 
  5364 * Pure: more efficient orders for basic syntactic entities: added
  5365 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  5366 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  5367 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  5368 orders now -- potential INCOMPATIBILITY for code that depends on a
  5369 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  5370 Library.sort_strings on result).
  5371 
  5372 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  5373 fold_types traverse types/terms from left to right, observing natural
  5374 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  5375 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  5376 
  5377 * Pure: name spaces have been refined, with significant changes of the
  5378 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  5379 to extern(_table).  The plain name entry path is superceded by a
  5380 general 'naming' context, which also includes the 'policy' to produce
  5381 a fully qualified name and external accesses of a fully qualified
  5382 name; NameSpace.extend is superceded by context dependent
  5383 Sign.declare_name.  Several theory and proof context operations modify
  5384 the naming context.  Especially note Theory.restore_naming and
  5385 ProofContext.restore_naming to get back to a sane state; note that
  5386 Theory.add_path is no longer sufficient to recover from
  5387 Theory.absolute_path in particular.
  5388 
  5389 * Pure: new flags short_names (default false) and unique_names
  5390 (default true) for controlling output of qualified names.  If
  5391 short_names is set, names are printed unqualified.  If unique_names is
  5392 reset, the name prefix is reduced to the minimum required to achieve
  5393 the original result when interning again, even if there is an overlap
  5394 with earlier declarations.
  5395 
  5396 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  5397 now 'extend', and 'merge' gets an additional Pretty.pp argument
  5398 (useful for printing error messages).  INCOMPATIBILITY.
  5399 
  5400 * Pure: major reorganization of the theory context.  Type Sign.sg and
  5401 Theory.theory are now identified, referring to the universal
  5402 Context.theory (see Pure/context.ML).  Actual signature and theory
  5403 content is managed as theory data.  The old code and interfaces were
  5404 spread over many files and structures; the new arrangement introduces
  5405 considerable INCOMPATIBILITY to gain more clarity:
  5406 
  5407   Context -- theory management operations (name, identity, inclusion,
  5408     parents, ancestors, merge, etc.), plus generic theory data;
  5409 
  5410   Sign -- logical signature and syntax operations (declaring consts,
  5411     types, etc.), plus certify/read for common entities;
  5412 
  5413   Theory -- logical theory operations (stating axioms, definitions,
  5414     oracles), plus a copy of logical signature operations (consts,
  5415     types, etc.); also a few basic management operations (Theory.copy,
  5416     Theory.merge, etc.)
  5417 
  5418 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  5419 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  5420 for convenience -- they merely return the theory.
  5421 
  5422 * Pure: type Type.tsig is superceded by theory in most interfaces.
  5423 
  5424 * Pure: the Isar proof context type is already defined early in Pure
  5425 as Context.proof (note that ProofContext.context and Proof.context are
  5426 aliases, where the latter is the preferred name).  This enables other
  5427 Isabelle components to refer to that type even before Isar is present.
  5428 
  5429 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  5430 typeK, constK, axiomK, oracleK), but provide explicit operations for
  5431 any of these kinds.  For example, Sign.intern typeK is now
  5432 Sign.intern_type, Theory.hide_space Sign.typeK is now
  5433 Theory.hide_types.  Also note that former
  5434 Theory.hide_classes/types/consts are now
  5435 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  5436 internalize their arguments!  INCOMPATIBILITY.
  5437 
  5438 * Pure: get_thm interface (of PureThy and ProofContext) expects
  5439 datatype thmref (with constructors Name and NameSelection) instead of
  5440 plain string -- INCOMPATIBILITY;
  5441 
  5442 * Pure: cases produced by proof methods specify options, where NONE
  5443 means to remove case bindings -- INCOMPATIBILITY in
  5444 (RAW_)METHOD_CASES.
  5445 
  5446 * Pure: the following operations retrieve axioms or theorems from a
  5447 theory node or theory hierarchy, respectively:
  5448 
  5449   Theory.axioms_of: theory -> (string * term) list
  5450   Theory.all_axioms_of: theory -> (string * term) list
  5451   PureThy.thms_of: theory -> (string * thm) list
  5452   PureThy.all_thms_of: theory -> (string * thm) list
  5453 
  5454 * Pure: print_tac now outputs the goal through the trace channel.
  5455 
  5456 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  5457 Reference Toplevel.debug (default false) controls detailed printing
  5458 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  5459 controls execution profiling -- set to 1 for time and 2 for space
  5460 (both increase the runtime).
  5461 
  5462 * Isar session: The initial use of ROOT.ML is now always timed,
  5463 i.e. the log will show the actual process times, in contrast to the
  5464 elapsed wall-clock time that the outer shell wrapper produces.
  5465 
  5466 * Simplifier: improved handling of bound variables (nameless
  5467 representation, avoid allocating new strings).  Simprocs that invoke
  5468 the Simplifier recursively should use Simplifier.inherit_bounds to
  5469 avoid local name clashes.  Failure to do so produces warnings
  5470 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  5471 for further details.
  5472 
  5473 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  5474 bindings for all theorems stored within a given theory; this may help
  5475 in porting non-Isar theories to Isar ones, while keeping ML proof
  5476 scripts for the time being.
  5477 
  5478 * ML operator HTML.with_charset specifies the charset begin used for
  5479 generated HTML files.  For example:
  5480 
  5481   HTML.with_charset "utf-8" use_thy "Hebrew";
  5482   HTML.with_charset "utf-8" use_thy "Chinese";
  5483 
  5484 
  5485 *** System ***
  5486 
  5487 * Allow symlinks to all proper Isabelle executables (Isabelle,
  5488 isabelle, isatool etc.).
  5489 
  5490 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  5491 isatool doc, isatool mkdir, display_drafts etc.).
  5492 
  5493 * isatool usedir: option -f allows specification of the ML file to be
  5494 used by Isabelle; default is ROOT.ML.
  5495 
  5496 * New isatool version outputs the version identifier of the Isabelle
  5497 distribution being used.
  5498 
  5499 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  5500 (containing Boolean satisfiability problems) into Isabelle/HOL
  5501 theories.
  5502 
  5503 
  5504 
  5505 New in Isabelle2004 (April 2004)
  5506 --------------------------------
  5507 
  5508 *** General ***
  5509 
  5510 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  5511   Replaces linorder.ML.
  5512 
  5513 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  5514   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  5515   (\<a>...\<z>), are now considered normal letters, and can therefore
  5516   be used anywhere where an ASCII letter (a...zA...Z) has until
  5517   now. COMPATIBILITY: This obviously changes the parsing of some
  5518   terms, especially where a symbol has been used as a binder, say
  5519   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  5520   as an identifier.  Fix it by inserting a space around former
  5521   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  5522   existing theory and ML files.
  5523 
  5524 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  5525 
  5526 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  5527   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  5528   a normal (but invisible) letter. For multiple letter subscripts repeat
  5529   \<^isub> like this: x\<^isub>1\<^isub>2.
  5530 
  5531 * Pure: There are now sub-/superscripts that can span more than one
  5532   character. Text between \<^bsub> and \<^esub> is set in subscript in
  5533   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  5534   superscript. The new control characters are not identifier parts.
  5535 
  5536 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5537   content of "..." to the latex file instead of \isacntrl... . The "..."
  5538   may consist of any printable characters excluding the end bracket >.
  5539 
  5540 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5541   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5542   declare constants "final", which prevents their being given a definition
  5543   later.  It is useful for constants whose behaviour is fixed axiomatically
  5544   rather than definitionally, such as the meta-logic connectives.
  5545 
  5546 * Pure: 'instance' now handles general arities with general sorts
  5547   (i.e. intersections of classes),
  5548 
  5549 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5550   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5551   It can be changed to alter the colors/layout of generated pages.
  5552 
  5553 
  5554 *** Isar ***
  5555 
  5556 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5557   cut_tac, subgoal_tac and thin_tac:
  5558   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5559     locales are no longer forced to write Isar proof scripts.
  5560     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5561     emulations.
  5562   - INCOMPATIBILITY: names of variables to be instantiated may no
  5563     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5564     This is consistent with the instantiation attribute "where".
  5565 
  5566 * Attributes "where" and "of":
  5567   - Now take type variables of instantiated theorem into account when reading
  5568     the instantiation string.  This fixes a bug that caused instantiated
  5569     theorems to have too special types in some circumstances.
  5570   - "where" permits explicit instantiations of type variables.
  5571 
  5572 * Calculation commands "moreover" and "also" no longer interfere with
  5573   current facts ("this"), admitting arbitrary combinations with "then"
  5574   and derived forms.
  5575 
  5576 * Locales:
  5577   - Goal statements involving the context element "includes" no longer
  5578     generate theorems with internal delta predicates (those ending on
  5579     "_axioms") in the premise.
  5580     Resolve particular premise with <locale>.intro to obtain old form.
  5581   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5582     specification and "includes" elements in goal statement.
  5583   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5584     [intro?] and [elim?] (respectively) by default.
  5585   - Experimental command for instantiation of locales in proof contexts:
  5586         instantiate <label>[<attrs>]: <loc>
  5587     Instantiates locale <loc> and adds all its theorems to the current context
  5588     taking into account their attributes.  Label and attrs are optional
  5589     modifiers, like in theorem declarations.  If present, names of
  5590     instantiated theorems are qualified with <label>, and the attributes
  5591     <attrs> are applied after any attributes these theorems might have already.
  5592       If the locale has assumptions, a chained fact of the form
  5593     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5594     are derived.  The command does not support old-style locales declared
  5595     with "locale (open)".
  5596       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5597 
  5598 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5599   (Isar) contexts.
  5600 
  5601 
  5602 *** HOL ***
  5603 
  5604 * Proof import: new image HOL4 contains the imported library from
  5605   the HOL4 system with about 2500 theorems. It is imported by
  5606   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5607   can be used like any other Isabelle image.  See
  5608   HOL/Import/HOL/README for more information.
  5609 
  5610 * Simplifier:
  5611   - Much improved handling of linear and partial orders.
  5612     Reasoners for linear and partial orders are set up for type classes
  5613     "linorder" and "order" respectively, and are added to the default simpset
  5614     as solvers.  This means that the simplifier can build transitivity chains
  5615     to solve goals from the assumptions.
  5616   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5617     of blast or auto after simplification become unnecessary because the goal
  5618     is solved by simplification already.
  5619 
  5620 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5621     all proved in axiomatic type classes for semirings, rings and fields.
  5622 
  5623 * Numerics:
  5624   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5625     now formalized using the Ring_and_Field theory mentioned above.
  5626   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5627     than before, because now they are set up once in a generic manner.
  5628   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5629     Look for the general versions in Ring_and_Field (and Power if they concern
  5630     exponentiation).
  5631 
  5632 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5633 
  5634 * Records:
  5635   - Record types are now by default printed with their type abbreviation
  5636     instead of the list of all field types. This can be configured via
  5637     the reference "print_record_type_abbr".
  5638   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5639     (not enabled by default).
  5640   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5641     EX x. x = sel r to True (not enabled by default).
  5642   - Tactic "record_split_simp_tac" to split and simplify records added.
  5643 
  5644 * 'specification' command added, allowing for definition by
  5645   specification.  There is also an 'ax_specification' command that
  5646   introduces the new constants axiomatically.
  5647 
  5648 * arith(_tac) is now able to generate counterexamples for reals as well.
  5649 
  5650 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5651 
  5652 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5653   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5654 
  5655 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5656   matrix theory to linear programming.
  5657 
  5658 * Unions and Intersections:
  5659   The latex output syntax of UN and INT has been changed
  5660   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5661   i.e. the index formulae has become a subscript.
  5662   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5663 
  5664 * Unions and Intersections over Intervals:
  5665   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5666   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5667   like in normal math, and corresponding versions for < and for intersection.
  5668 
  5669 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5670   lexicographic dictonary ordering has been added as "lexord".
  5671 
  5672 * ML: the legacy theory structures Int and List have been removed. They had
  5673   conflicted with ML Basis Library structures having the same names.
  5674 
  5675 * 'refute' command added to search for (finite) countermodels.  Only works
  5676   for a fragment of HOL.  The installation of an external SAT solver is
  5677   highly recommended.  See "HOL/Refute.thy" for details.
  5678 
  5679 * 'quickcheck' command: Allows to find counterexamples by evaluating
  5680   formulae under an assignment of free variables to random values.
  5681   In contrast to 'refute', it can deal with inductive datatypes,
  5682   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  5683   for examples.
  5684 
  5685 
  5686 *** HOLCF ***
  5687 
  5688 * Streams now come with concatenation and are part of the HOLCF image
  5689 
  5690 
  5691 
  5692 New in Isabelle2003 (May 2003)
  5693 ------------------------------
  5694 
  5695 *** General ***
  5696 
  5697 * Provers/simplifier:
  5698 
  5699   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  5700     Assumptions are now subject to complete mutual simplification,
  5701     not just from left to right. The simplifier now preserves
  5702     the order of assumptions.
  5703 
  5704     Potential INCOMPATIBILITY:
  5705 
  5706     -- simp sometimes diverges where the old version did
  5707        not, e.g. invoking simp on the goal
  5708 
  5709         [| P (f x); y = x; f x = f y |] ==> Q
  5710 
  5711        now gives rise to the infinite reduction sequence
  5712 
  5713         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  5714 
  5715        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  5716        kind of problem.
  5717 
  5718     -- Tactics combining classical reasoner and simplification (such as auto)
  5719        are also affected by this change, because many of them rely on
  5720        simp. They may sometimes diverge as well or yield a different numbers
  5721        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  5722        in case of problems. Sometimes subsequent calls to the classical
  5723        reasoner will fail because a preceeding call to the simplifier too
  5724        eagerly simplified the goal, e.g. deleted redundant premises.
  5725 
  5726   - The simplifier trace now shows the names of the applied rewrite rules
  5727 
  5728   - You can limit the number of recursive invocations of the simplifier
  5729     during conditional rewriting (where the simplifie tries to solve the
  5730     conditions before applying the rewrite rule):
  5731     ML "simp_depth_limit := n"
  5732     where n is an integer. Thus you can force termination where previously
  5733     the simplifier would diverge.
  5734 
  5735   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  5736 
  5737   - No longer aborts on failed congruence proof.  Instead, the
  5738     congruence is ignored.
  5739 
  5740 * Pure: New generic framework for extracting programs from constructive
  5741   proofs. See HOL/Extraction.thy for an example instantiation, as well
  5742   as HOL/Extraction for some case studies.
  5743 
  5744 * Pure: The main goal of the proof state is no longer shown by default, only
  5745 the subgoals. This behaviour is controlled by a new flag.
  5746    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  5747 (ML: Proof.show_main_goal).
  5748 
  5749 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  5750 rules whose conclusion matches subgoal 1:
  5751       PG menu: Isabelle/Isar -> Show me -> matching rules
  5752 The rules are ordered by how closely they match the subgoal.
  5753 In particular, rules that solve a subgoal outright are displayed first
  5754 (or rather last, the way they are printed).
  5755 (ML: ProofGeneral.print_intros())
  5756 
  5757 * Pure: New flag trace_unify_fail causes unification to print
  5758 diagnostic information (PG: in trace buffer) when it fails. This is
  5759 useful for figuring out why single step proofs like rule, erule or
  5760 assumption failed.
  5761 
  5762 * Pure: Locale specifications now produce predicate definitions
  5763 according to the body of text (covering assumptions modulo local
  5764 definitions); predicate "loc_axioms" covers newly introduced text,
  5765 while "loc" is cumulative wrt. all included locale expressions; the
  5766 latter view is presented only on export into the global theory
  5767 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  5768 on the old view without predicates;
  5769 
  5770 * Pure: predefined locales "var" and "struct" are useful for sharing
  5771 parameters (as in CASL, for example); just specify something like
  5772 ``var x + var y + struct M'' as import;
  5773 
  5774 * Pure: improved thms_containing: proper indexing of facts instead of
  5775 raw theorems; check validity of results wrt. current name space;
  5776 include local facts of proof configuration (also covers active
  5777 locales), cover fixed variables in index; may use "_" in term
  5778 specification; an optional limit for the number of printed facts may
  5779 be given (the default is 40);
  5780 
  5781 * Pure: disallow duplicate fact bindings within new-style theory files
  5782 (batch-mode only);
  5783 
  5784 * Provers: improved induct method: assumptions introduced by case
  5785 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  5786 the goal statement); "foo" still refers to all facts collectively;
  5787 
  5788 * Provers: the function blast.overloaded has been removed: all constants
  5789 are regarded as potentially overloaded, which improves robustness in exchange
  5790 for slight decrease in efficiency;
  5791 
  5792 * Provers/linorder: New generic prover for transitivity reasoning over
  5793 linear orders.  Note: this prover is not efficient!
  5794 
  5795 * Isar: preview of problems to finish 'show' now produce an error
  5796 rather than just a warning (in interactive mode);
  5797 
  5798 
  5799 *** HOL ***
  5800 
  5801 * arith(_tac)
  5802 
  5803  - Produces a counter example if it cannot prove a goal.
  5804    Note that the counter example may be spurious if the goal is not a formula
  5805    of quantifier-free linear arithmetic.
  5806    In ProofGeneral the counter example appears in the trace buffer.
  5807 
  5808  - Knows about div k and mod k where k is a numeral of type nat or int.
  5809 
  5810  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  5811    linear arithmetic fails. This takes account of quantifiers and divisibility.
  5812    Presburger arithmetic can also be called explicitly via presburger(_tac).
  5813 
  5814 * simp's arithmetic capabilities have been enhanced a bit: it now
  5815 takes ~= in premises into account (by performing a case split);
  5816 
  5817 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  5818 are distributed over a sum of terms;
  5819 
  5820 * New tactic "trans_tac" and method "trans" instantiate
  5821 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  5822 "<=", "<" and "=").
  5823 
  5824 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  5825 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  5826 
  5827 * 'typedef' command has new option "open" to suppress the set
  5828 definition;
  5829 
  5830 * functions Min and Max on finite sets have been introduced (theory
  5831 Finite_Set);
  5832 
  5833 * attribute [symmetric] now works for relations as well; it turns
  5834 (x,y) : R^-1 into (y,x) : R, and vice versa;
  5835 
  5836 * induct over a !!-quantified statement (say !!x1..xn):
  5837   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  5838 
  5839 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  5840 %x. None. Warning: empty_def now refers to the previously hidden definition
  5841 of the empty set.
  5842 
  5843 * Algebra: formalization of classical algebra.  Intended as base for
  5844 any algebraic development in Isabelle.  Currently covers group theory
  5845 (up to Sylow's theorem) and ring theory (Universal Property of
  5846 Univariate Polynomials).  Contributions welcome;
  5847 
  5848 * GroupTheory: deleted, since its material has been moved to Algebra;
  5849 
  5850 * Complex: new directory of the complex numbers with numeric constants,
  5851 nonstandard complex numbers, and some complex analysis, standard and
  5852 nonstandard (Jacques Fleuriot);
  5853 
  5854 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  5855 
  5856 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  5857 Fleuriot);
  5858 
  5859 * Real/HahnBanach: updated and adapted to locales;
  5860 
  5861 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  5862 Gray and Kramer);
  5863 
  5864 * UNITY: added the Meier-Sanders theory of progress sets;
  5865 
  5866 * MicroJava: bytecode verifier and lightweight bytecode verifier
  5867 as abstract algorithms, instantiated to the JVM;
  5868 
  5869 * Bali: Java source language formalization. Type system, operational
  5870 semantics, axiomatic semantics. Supported language features:
  5871 classes, interfaces, objects,virtual methods, static methods,
  5872 static/instance fields, arrays, access modifiers, definite
  5873 assignment, exceptions.
  5874 
  5875 
  5876 *** ZF ***
  5877 
  5878 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  5879 universe, etc.);
  5880 
  5881 * Main ZF: virtually all theories converted to new-style format;
  5882 
  5883 
  5884 *** ML ***
  5885 
  5886 * Pure: Tactic.prove provides sane interface for internal proofs;
  5887 omits the infamous "standard" operation, so this is more appropriate
  5888 than prove_goalw_cterm in many situations (e.g. in simprocs);
  5889 
  5890 * Pure: improved error reporting of simprocs;
  5891 
  5892 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  5893 up simprocs;
  5894 
  5895 
  5896 *** Document preparation ***
  5897 
  5898 * uses \par instead of \\ for line breaks in theory text. This may
  5899 shift some page breaks in large documents. To get the old behaviour
  5900 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  5901 
  5902 * minimized dependencies of isabelle.sty and isabellesym.sty on
  5903 other packages
  5904 
  5905 * \<euro> now needs package babel/greek instead of marvosym (which
  5906 broke \Rightarrow)
  5907 
  5908 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  5909 textcomp package)
  5910 
  5911 
  5912 
  5913 New in Isabelle2002 (March 2002)
  5914 --------------------------------
  5915 
  5916 *** Document preparation ***
  5917 
  5918 * greatly simplified document preparation setup, including more
  5919 graceful interpretation of isatool usedir -i/-d/-D options, and more
  5920 instructive isatool mkdir; users should basically be able to get
  5921 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  5922 users may run a separate document processing stage manually like this:
  5923 "isatool usedir -D output HOL Test && isatool document Test/output";
  5924 
  5925 * theory dependency graph may now be incorporated into documents;
  5926 isatool usedir -g true will produce session_graph.eps/.pdf for use
  5927 with \includegraphics of LaTeX;
  5928 
  5929 * proper spacing of consecutive markup elements, especially text
  5930 blocks after section headings;
  5931 
  5932 * support bold style (for single symbols only), input syntax is like
  5933 this: "\<^bold>\<alpha>" or "\<^bold>A";
  5934 
  5935 * \<bullet> is now output as bold \cdot by default, which looks much
  5936 better in printed text;
  5937 
  5938 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  5939 note that these symbols are currently unavailable in Proof General /
  5940 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  5941 
  5942 * isatool latex no longer depends on changed TEXINPUTS, instead
  5943 isatool document copies the Isabelle style files to the target
  5944 location;
  5945 
  5946 
  5947 *** Isar ***
  5948 
  5949 * Pure/Provers: improved proof by cases and induction;
  5950   - 'case' command admits impromptu naming of parameters (such as
  5951     "case (Suc n)");
  5952   - 'induct' method divinates rule instantiation from the inductive
  5953     claim; no longer requires excessive ?P bindings for proper
  5954     instantiation of cases;
  5955   - 'induct' method properly enumerates all possibilities of set/type
  5956     rules; as a consequence facts may be also passed through *type*
  5957     rules without further ado;
  5958   - 'induct' method now derives symbolic cases from the *rulified*
  5959     rule (before it used to rulify cases stemming from the internal
  5960     atomized version); this means that the context of a non-atomic
  5961     statement becomes is included in the hypothesis, avoiding the
  5962     slightly cumbersome show "PROP ?case" form;
  5963   - 'induct' may now use elim-style induction rules without chaining
  5964     facts, using ``missing'' premises from the goal state; this allows
  5965     rules stemming from inductive sets to be applied in unstructured
  5966     scripts, while still benefitting from proper handling of non-atomic
  5967     statements; NB: major inductive premises need to be put first, all
  5968     the rest of the goal is passed through the induction;
  5969   - 'induct' proper support for mutual induction involving non-atomic
  5970     rule statements (uses the new concept of simultaneous goals, see
  5971     below);
  5972   - append all possible rule selections, but only use the first
  5973     success (no backtracking);
  5974   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  5975   - undeclared rule case names default to numbers 1, 2, 3, ...;
  5976   - added 'print_induct_rules' (covered by help item in recent Proof
  5977     General versions);
  5978   - moved induct/cases attributes to Pure, methods to Provers;
  5979   - generic method setup instantiated for FOL and HOL;
  5980 
  5981 * Pure: support multiple simultaneous goal statements, for example
  5982 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  5983 meta-level mechanism, this acts as if several individual goals had
  5984 been stated separately; in particular common proof methods need to be
  5985 repeated in order to cover all claims; note that a single elimination
  5986 step is *not* sufficient to establish the two conjunctions, so this
  5987 fails:
  5988 
  5989   assume "A & B" then have A and B ..   (*".." fails*)
  5990 
  5991 better use "obtain" in situations as above; alternative refer to
  5992 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  5993 
  5994 * Pure: proper integration with ``locales''; unlike the original
  5995 version by Florian Kammller, Isar locales package high-level proof
  5996 contexts rather than raw logical ones (e.g. we admit to include
  5997 attributes everywhere); operations on locales include merge and
  5998 rename; support for implicit arguments (``structures''); simultaneous
  5999 type-inference over imports and text; see also HOL/ex/Locales.thy for
  6000 some examples;
  6001 
  6002 * Pure: the following commands have been ``localized'', supporting a
  6003 target locale specification "(in name)": 'lemma', 'theorem',
  6004 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  6005 stored both within the locale and at the theory level (exported and
  6006 qualified by the locale name);
  6007 
  6008 * Pure: theory goals may now be specified in ``long'' form, with
  6009 ad-hoc contexts consisting of arbitrary locale elements. for example
  6010 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  6011 definitions may be given, too); the result is a meta-level rule with
  6012 the context elements being discharged in the obvious way;
  6013 
  6014 * Pure: new proof command 'using' allows to augment currently used
  6015 facts after a goal statement ('using' is syntactically analogous to
  6016 'apply', but acts on the goal's facts only); this allows chained facts
  6017 to be separated into parts given before and after a claim, as in
  6018 ``from a and b have C using d and e <proof>'';
  6019 
  6020 * Pure: renamed "antecedent" case to "rule_context";
  6021 
  6022 * Pure: new 'judgment' command records explicit information about the
  6023 object-logic embedding (used by several tools internally); no longer
  6024 use hard-wired "Trueprop";
  6025 
  6026 * Pure: added 'corollary' command;
  6027 
  6028 * Pure: fixed 'token_translation' command;
  6029 
  6030 * Pure: removed obsolete 'exported' attribute;
  6031 
  6032 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  6033 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  6034 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  6035 
  6036 * Pure: method 'atomize' presents local goal premises as object-level
  6037 statements (atomic meta-level propositions); setup controlled via
  6038 rewrite rules declarations of 'atomize' attribute; example
  6039 application: 'induct' method with proper rule statements in improper
  6040 proof *scripts*;
  6041 
  6042 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  6043 now consider the syntactic context of assumptions, giving a better
  6044 chance to get type-inference of the arguments right (this is
  6045 especially important for locales);
  6046 
  6047 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  6048 mode;
  6049 
  6050 * Pure/obtain: the formal conclusion "thesis", being marked as
  6051 ``internal'', may no longer be reference directly in the text;
  6052 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  6053 situations;
  6054 
  6055 * Pure: generic 'sym' attribute which declares a rule both as pure
  6056 'elim?' and for the 'symmetric' operation;
  6057 
  6058 * Pure: marginal comments ``--'' may now occur just anywhere in the
  6059 text; the fixed correlation with particular command syntax has been
  6060 discontinued;
  6061 
  6062 * Pure: new method 'rules' is particularly well-suited for proof
  6063 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  6064 but often produces more compact proof terms with less detours;
  6065 
  6066 * Pure/Provers/classical: simplified integration with pure rule
  6067 attributes and methods; the classical "intro?/elim?/dest?"
  6068 declarations coincide with the pure ones; the "rule" method no longer
  6069 includes classically swapped intros; "intro" and "elim" methods no
  6070 longer pick rules from the context; also got rid of ML declarations
  6071 AddXIs/AddXEs/AddXDs; all of this has some potential for
  6072 INCOMPATIBILITY;
  6073 
  6074 * Provers/classical: attribute 'swapped' produces classical inversions
  6075 of introduction rules;
  6076 
  6077 * Provers/simplifier: 'simplified' attribute may refer to explicit
  6078 rules instead of full simplifier context; 'iff' attribute handles
  6079 conditional rules;
  6080 
  6081 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  6082 
  6083 * HOL: 'recdef' now fails on unfinished automated proofs, use
  6084 "(permissive)" option to recover old behavior;
  6085 
  6086 * HOL: 'inductive' no longer features separate (collective) attributes
  6087 for 'intros' (was found too confusing);
  6088 
  6089 * HOL: properly declared induction rules less_induct and
  6090 wf_induct_rule;
  6091 
  6092 
  6093 *** HOL ***
  6094 
  6095 * HOL: moved over to sane numeral syntax; the new policy is as
  6096 follows:
  6097 
  6098   - 0 and 1 are polymorphic constants, which are defined on any
  6099   numeric type (nat, int, real etc.);
  6100 
  6101   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  6102   binary representation internally;
  6103 
  6104   - type nat has special constructor Suc, and generally prefers Suc 0
  6105   over 1::nat and Suc (Suc 0) over 2::nat;
  6106 
  6107 This change may cause significant problems of INCOMPATIBILITY; here
  6108 are some hints on converting existing sources:
  6109 
  6110   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  6111   entities, so expressions involving "-" (unary or binary minus) need
  6112   to be spaced properly;
  6113 
  6114   - existing occurrences of "1" may need to be constraint "1::nat" or
  6115   even replaced by Suc 0; similar for old "2";
  6116 
  6117   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  6118 
  6119   - remove all special provisions on numerals in proofs;
  6120 
  6121 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  6122 representation (depends on bin_arith_simps in the default context);
  6123 
  6124 * HOL: symbolic syntax for x^2 (numeral 2);
  6125 
  6126 * HOL: the class of all HOL types is now called "type" rather than
  6127 "term"; INCOMPATIBILITY, need to adapt references to this type class
  6128 in axclass/classes, instance/arities, and (usually rare) occurrences
  6129 in typings (of consts etc.); internally the class is called
  6130 "HOL.type", ML programs should refer to HOLogic.typeS;
  6131 
  6132 * HOL/record package improvements:
  6133   - new derived operations "fields" to build a partial record section,
  6134     "extend" to promote a fixed record to a record scheme, and
  6135     "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*
  6136     declared as simp by default;
  6137   - shared operations ("more", "fields", etc.) now need to be always
  6138     qualified) --- potential INCOMPATIBILITY;
  6139   - removed "make_scheme" operations (use "make" with "extend") --
  6140     INCOMPATIBILITY;
  6141   - removed "more" class (simply use "term") -- INCOMPATIBILITY;
  6142   - provides cases/induct rules for use with corresponding Isar
  6143     methods (for concrete records, record schemes, concrete more
  6144     parts, and schematic more parts -- in that order);
  6145   - internal definitions directly based on a light-weight abstract
  6146     theory of product types over typedef rather than datatype;
  6147 
  6148 * HOL: generic code generator for generating executable ML code from
  6149 specifications; specific support for HOL constructs such as inductive
  6150 datatypes and sets, as well as recursive functions; can be invoked
  6151 via 'generate_code' theory section;
  6152 
  6153 * HOL: canonical cases/induct rules for n-tuples (n = 3..7);
  6154 
  6155 * HOL: consolidated and renamed several theories.  In particular:
  6156         Ord.thy has been absorbed into HOL.thy
  6157         String.thy has been absorbed into List.thy
  6158 
  6159 * HOL: concrete setsum syntax "\<Sum>i:A. b" == "setsum (%i. b) A"
  6160 (beware of argument permutation!);
  6161 
  6162 * HOL: linorder_less_split superseded by linorder_cases;
  6163 
  6164 * HOL/List: "nodups" renamed to "distinct";
  6165 
  6166 * HOL: added "The" definite description operator; move Hilbert's "Eps"
  6167 to peripheral theory "Hilbert_Choice"; some INCOMPATIBILITIES:
  6168   - Ex_def has changed, now need to use some_eq_ex
  6169 
  6170 * HOL: made split_all_tac safe; EXISTING PROOFS MAY FAIL OR LOOP, so
  6171 in this (rare) case use:
  6172 
  6173   delSWrapper "split_all_tac"
  6174   addSbefore ("unsafe_split_all_tac", unsafe_split_all_tac)
  6175 
  6176 * HOL: added safe wrapper "split_conv_tac" to claset; EXISTING PROOFS
  6177 MAY FAIL;
  6178 
  6179 * HOL: introduced f^n = f o ... o f; warning: due to the limits of
  6180 Isabelle's type classes, ^ on functions and relations has too general
  6181 a domain, namely ('a * 'b) set and 'a => 'b; this means that it may be
  6182 necessary to attach explicit type constraints;
  6183 
  6184 * HOL/Relation: the prefix name of the infix "O" has been changed from
  6185 "comp" to "rel_comp"; INCOMPATIBILITY: a few theorems have been
  6186 renamed accordingly (eg "compI" -> "rel_compI").
  6187 
  6188 * HOL: syntax translations now work properly with numerals and records
  6189 expressions;
  6190 
  6191 * HOL: bounded abstraction now uses syntax "%" / "\<lambda>" instead
  6192 of "lam" -- INCOMPATIBILITY;
  6193 
  6194 * HOL: got rid of some global declarations (potential INCOMPATIBILITY
  6195 for ML tools): const "()" renamed "Product_Type.Unity", type "unit"
  6196 renamed "Product_Type.unit";
  6197 
  6198 * HOL: renamed rtrancl_into_rtrancl2 to converse_rtrancl_into_rtrancl
  6199 
  6200 * HOL: removed obsolete theorem "optionE" (use "option.exhaust", or
  6201 the "cases" method);
  6202 
  6203 * HOL/GroupTheory: group theory examples including Sylow's theorem (by
  6204 Florian Kammller);
  6205 
  6206 * HOL/IMP: updated and converted to new-style theory format; several
  6207 parts turned into readable document, with proper Isar proof texts and
  6208 some explanations (by Gerwin Klein);
  6209 
  6210 * HOL-Real: added Complex_Numbers (by Gertrud Bauer);
  6211 
  6212 * HOL-Hyperreal is now a logic image;
  6213 
  6214 
  6215 *** HOLCF ***
  6216 
  6217 * Isar: consts/constdefs supports mixfix syntax for continuous
  6218 operations;
  6219 
  6220 * Isar: domain package adapted to new-style theory format, e.g. see
  6221 HOLCF/ex/Dnat.thy;
  6222 
  6223 * theory Lift: proper use of rep_datatype lift instead of ML hacks --
  6224 potential INCOMPATIBILITY; now use plain induct_tac instead of former
  6225 lift.induct_tac, always use UU instead of Undef;
  6226 
  6227 * HOLCF/IMP: updated and converted to new-style theory;
  6228 
  6229 
  6230 *** ZF ***
  6231 
  6232 * Isar: proper integration of logic-specific tools and packages,
  6233 including theory commands '(co)inductive', '(co)datatype',
  6234 'rep_datatype', 'inductive_cases', as well as methods 'ind_cases',
  6235 'induct_tac', 'case_tac', and 'typecheck' (with attribute 'TC');
  6236 
  6237 * theory Main no longer includes AC; for the Axiom of Choice, base
  6238 your theory on Main_ZFC;
  6239 
  6240 * the integer library now covers quotients and remainders, with many
  6241 laws relating division to addition, multiplication, etc.;
  6242 
  6243 * ZF/UNITY: Chandy and Misra's UNITY is now available in ZF, giving a
  6244 typeless version of the formalism;
  6245 
  6246 * ZF/AC, Coind, IMP, Resid: updated and converted to new-style theory
  6247 format;
  6248 
  6249 * ZF/Induct: new directory for examples of inductive definitions,
  6250 including theory Multiset for multiset orderings; converted to
  6251 new-style theory format;
  6252 
  6253 * ZF: many new theorems about lists, ordinals, etc.;
  6254 
  6255 
  6256 *** General ***
  6257 
  6258 * Pure/kernel: meta-level proof terms (by Stefan Berghofer); reference
  6259 variable proof controls level of detail: 0 = no proofs (only oracle
  6260 dependencies), 1 = lemma dependencies, 2 = compact proof terms; see
  6261 also ref manual for further ML interfaces;
  6262 
  6263 * Pure/axclass: removed obsolete ML interface
  6264 goal_subclass/goal_arity;
  6265 
  6266 * Pure/syntax: new token syntax "num" for plain numerals (without "#"
  6267 of "xnum"); potential INCOMPATIBILITY, since -0, -1 etc. are now
  6268 separate tokens, so expressions involving minus need to be spaced
  6269 properly;
  6270 
  6271 * Pure/syntax: support non-oriented infixes, using keyword "infix"
  6272 rather than "infixl" or "infixr";
  6273 
  6274 * Pure/syntax: concrete syntax for dummy type variables admits genuine
  6275 sort constraint specifications in type inference; e.g. "x::_::foo"
  6276 ensures that the type of "x" is of sort "foo" (but not necessarily a
  6277 type variable);
  6278 
  6279 * Pure/syntax: print modes "type_brackets" and "no_type_brackets"
  6280 control output of nested => (types); the default behavior is
  6281 "type_brackets";
  6282 
  6283 * Pure/syntax: builtin parse translation for "_constify" turns valued
  6284 tokens into AST constants;
  6285 
  6286 * Pure/syntax: prefer later declarations of translations and print
  6287 translation functions; potential INCOMPATIBILITY: need to reverse
  6288 multiple declarations for same syntax element constant;
  6289 
  6290 * Pure/show_hyps reset by default (in accordance to existing Isar
  6291 practice);
  6292 
  6293 * Provers/classical: renamed addaltern to addafter, addSaltern to
  6294 addSafter;
  6295 
  6296 * Provers/clasimp: ``iff'' declarations now handle conditional rules
  6297 as well;
  6298 
  6299 * system: tested support for MacOS X; should be able to get Isabelle +
  6300 Proof General to work in a plain Terminal after installing Poly/ML
  6301 (e.g. from the Isabelle distribution area) and GNU bash alone
  6302 (e.g. from http://www.apple.com); full X11, XEmacs and X-Symbol
  6303 support requires further installations, e.g. from
  6304 http://fink.sourceforge.net/);
  6305 
  6306 * system: support Poly/ML 4.1.1 (able to manage larger heaps);
  6307 
  6308 * system: reduced base memory usage by Poly/ML (approx. 20 MB instead
  6309 of 40 MB), cf. ML_OPTIONS;
  6310 
  6311 * system: Proof General keywords specification is now part of the
  6312 Isabelle distribution (see etc/isar-keywords.el);
  6313 
  6314 * system: support for persistent Proof General sessions (refrain from
  6315 outdating all loaded theories on startup); user may create writable
  6316 logic images like this: ``isabelle -q HOL Test'';
  6317 
  6318 * system: smart selection of Isabelle process versus Isabelle
  6319 interface, accommodates case-insensitive file systems (e.g. HFS+); may
  6320 run both "isabelle" and "Isabelle" even if file names are badly
  6321 damaged (executable inspects the case of the first letter of its own
  6322 name); added separate "isabelle-process" and "isabelle-interface";
  6323 
  6324 * system: refrain from any attempt at filtering input streams; no
  6325 longer support ``8bit'' encoding of old isabelle font, instead proper
  6326 iso-latin characters may now be used; the related isatools
  6327 "symbolinput" and "nonascii" have disappeared as well;
  6328 
  6329 * system: removed old "xterm" interface (the print modes "xterm" and
  6330 "xterm_color" are still available for direct use in a suitable
  6331 terminal);
  6332 
  6333 
  6334 
  6335 New in Isabelle99-2 (February 2001)
  6336 -----------------------------------
  6337 
  6338 *** Overview of INCOMPATIBILITIES ***
  6339 
  6340 * HOL: please note that theories in the Library and elsewhere often use the
  6341 new-style (Isar) format; to refer to their theorems in an ML script you must
  6342 bind them to ML identifers by e.g.      val thm_name = thm "thm_name";
  6343 
  6344 * HOL: inductive package no longer splits induction rule aggressively,
  6345 but only as far as specified by the introductions given; the old
  6346 format may be recovered via ML function complete_split_rule or attribute
  6347 'split_rule (complete)';
  6348 
  6349 * HOL: induct renamed to lfp_induct, lfp_Tarski to lfp_unfold,
  6350 gfp_Tarski to gfp_unfold;
  6351 
  6352 * HOL: contrapos, contrapos2 renamed to contrapos_nn, contrapos_pp;
  6353 
  6354 * HOL: infix "dvd" now has priority 50 rather than 70 (because it is a
  6355 relation); infix "^^" has been renamed "``"; infix "``" has been
  6356 renamed "`"; "univalent" has been renamed "single_valued";
  6357 
  6358 * HOL/Real: "rinv" and "hrinv" replaced by overloaded "inverse"
  6359 operation;
  6360 
  6361 * HOLCF: infix "`" has been renamed "$"; the symbol syntax is \<cdot>;
  6362 
  6363 * Isar: 'obtain' no longer declares "that" fact as simp/intro;
  6364 
  6365 * Isar/HOL: method 'induct' now handles non-atomic goals; as a
  6366 consequence, it is no longer monotonic wrt. the local goal context
  6367 (which is now passed through the inductive cases);
  6368 
  6369 * Document preparation: renamed standard symbols \<ll> to \<lless> and
  6370 \<gg> to \<ggreater>;
  6371 
  6372 
  6373 *** Document preparation ***
  6374 
  6375 * \isabellestyle{NAME} selects version of Isabelle output (currently
  6376 available: are "it" for near math-mode best-style output, "sl" for
  6377 slanted text style, and "tt" for plain type-writer; if no
  6378 \isabellestyle command is given, output is according to slanted
  6379 type-writer);
  6380 
  6381 * support sub/super scripts (for single symbols only), input syntax is
  6382 like this: "A\<^sup>*" or "A\<^sup>\<star>";
  6383 
  6384 * some more standard symbols; see Appendix A of the system manual for
  6385 the complete list of symbols defined in isabellesym.sty;
  6386 
  6387 * improved isabelle style files; more abstract symbol implementation
  6388 (should now use \isamath{...} and \isatext{...} in custom symbol
  6389 definitions);
  6390 
  6391 * antiquotation @{goals} and @{subgoals} for output of *dynamic* goals
  6392 state; Note that presentation of goal states does not conform to
  6393 actual human-readable proof documents.  Please do not include goal
  6394 states into document output unless you really know what you are doing!
  6395 
  6396 * proper indentation of antiquoted output with proportional LaTeX
  6397 fonts;
  6398 
  6399 * no_document ML operator temporarily disables LaTeX document
  6400 generation;
  6401 
  6402 * isatool unsymbolize tunes sources for plain ASCII communication;
  6403 
  6404 
  6405 *** Isar ***
  6406 
  6407 * Pure: Isar now suffers initial goal statements to contain unbound
  6408 schematic variables (this does not conform to actual readable proof
  6409 documents, due to unpredictable outcome and non-compositional proof
  6410 checking); users who know what they are doing may use schematic goals
  6411 for Prolog-style synthesis of proven results;
  6412 
  6413 * Pure: assumption method (an implicit finishing) now handles actual
  6414 rules as well;
  6415 
  6416 * Pure: improved 'obtain' --- moved to Pure, insert "that" into
  6417 initial goal, declare "that" only as Pure intro (only for single
  6418 steps); the "that" rule assumption may now be involved in implicit
  6419 finishing, thus ".." becomes a feasible for trivial obtains;
  6420 
  6421 * Pure: default proof step now includes 'intro_classes'; thus trivial
  6422 instance proofs may be performed by "..";
  6423 
  6424 * Pure: ?thesis / ?this / "..." now work for pure meta-level
  6425 statements as well;
  6426 
  6427 * Pure: more robust selection of calculational rules;
  6428 
  6429 * Pure: the builtin notion of 'finished' goal now includes the ==-refl
  6430 rule (as well as the assumption rule);
  6431 
  6432 * Pure: 'thm_deps' command visualizes dependencies of theorems and
  6433 lemmas, using the graph browser tool;
  6434 
  6435 * Pure: predict failure of "show" in interactive mode;
  6436 
  6437 * Pure: 'thms_containing' now takes actual terms as arguments;
  6438 
  6439 * HOL: improved method 'induct' --- now handles non-atomic goals
  6440 (potential INCOMPATIBILITY); tuned error handling;
  6441 
  6442 * HOL: cases and induct rules now provide explicit hints about the
  6443 number of facts to be consumed (0 for "type" and 1 for "set" rules);
  6444 any remaining facts are inserted into the goal verbatim;
  6445 
  6446 * HOL: local contexts (aka cases) may now contain term bindings as
  6447 well; the 'cases' and 'induct' methods new provide a ?case binding for
  6448 the result to be shown in each case;
  6449 
  6450 * HOL: added 'recdef_tc' command;
  6451 
  6452 * isatool convert assists in eliminating legacy ML scripts;
  6453 
  6454 
  6455 *** HOL ***
  6456 
  6457 * HOL/Library: a collection of generic theories to be used together
  6458 with main HOL; the theory loader path already includes this directory
  6459 by default; the following existing theories have been moved here:
  6460 HOL/Induct/Multiset, HOL/Induct/Acc (as Accessible_Part), HOL/While
  6461 (as While_Combinator), HOL/Lex/Prefix (as List_Prefix);
  6462 
  6463 * HOL/Unix: "Some aspects of Unix file-system security", a typical
  6464 modelling and verification task performed in Isabelle/HOL +
  6465 Isabelle/Isar + Isabelle document preparation (by Markus Wenzel).
  6466 
  6467 * HOL/Algebra: special summation operator SUM no longer exists, it has
  6468 been replaced by setsum; infix 'assoc' now has priority 50 (like
  6469 'dvd'); axiom 'one_not_zero' has been moved from axclass 'ring' to
  6470 'domain', this makes the theory consistent with mathematical
  6471 literature;
  6472 
  6473 * HOL basics: added overloaded operations "inverse" and "divide"
  6474 (infix "/"), syntax for generic "abs" operation, generic summation
  6475 operator \<Sum>;
  6476 
  6477 * HOL/typedef: simplified package, provide more useful rules (see also
  6478 HOL/subset.thy);
  6479 
  6480 * HOL/datatype: induction rule for arbitrarily branching datatypes is
  6481 now expressed as a proper nested rule (old-style tactic scripts may
  6482 require atomize_strip_tac to cope with non-atomic premises);
  6483 
  6484 * HOL: renamed theory "Prod" to "Product_Type", renamed "split" rule
  6485 to "split_conv" (old name still available for compatibility);
  6486 
  6487 * HOL: improved concrete syntax for strings (e.g. allows translation
  6488 rules with string literals);
  6489 
  6490 * HOL-Real-Hyperreal: this extends HOL-Real with the hyperreals
  6491  and Fleuriot's mechanization of analysis, including the transcendental
  6492  functions for the reals;
  6493 
  6494 * HOL/Real, HOL/Hyperreal: improved arithmetic simplification;
  6495 
  6496 
  6497 *** CTT ***
  6498 
  6499 * CTT: x-symbol support for Pi, Sigma, -->, : (membership); note that
  6500 "lam" is displayed as TWO lambda-symbols
  6501 
  6502 * CTT: theory Main now available, containing everything (that is, Bool
  6503 and Arith);
  6504 
  6505 
  6506 *** General ***
  6507 
  6508 * Pure: the Simplifier has been implemented properly as a derived rule
  6509 outside of the actual kernel (at last!); the overall performance
  6510 penalty in practical applications is about 50%, while reliability of
  6511 the Isabelle inference kernel has been greatly improved;
  6512 
  6513 * print modes "brackets" and "no_brackets" control output of nested =>
  6514 (types) and ==> (props); the default behaviour is "brackets";
  6515 
  6516 * Provers: fast_tac (and friends) now handle actual object-logic rules
  6517 as assumptions as well;
  6518 
  6519 * system: support Poly/ML 4.0;
  6520 
  6521 * system: isatool install handles KDE version 1 or 2;
  6522 
  6523 
  6524 
  6525 New in Isabelle99-1 (October 2000)
  6526 ----------------------------------
  6527 
  6528 *** Overview of INCOMPATIBILITIES ***
  6529 
  6530 * HOL: simplification of natural numbers is much changed; to partly
  6531 recover the old behaviour (e.g. to prevent n+n rewriting to #2*n)
  6532 issue the following ML commands:
  6533 
  6534   Delsimprocs Nat_Numeral_Simprocs.cancel_numerals;
  6535   Delsimprocs [Nat_Numeral_Simprocs.combine_numerals];
  6536 
  6537 * HOL: simplification no longer dives into case-expressions; this is
  6538 controlled by "t.weak_case_cong" for each datatype t;
  6539 
  6540 * HOL: nat_less_induct renamed to less_induct;
  6541 
  6542 * HOL: systematic renaming of the SOME (Eps) rules, may use isatool
  6543 fixsome to patch .thy and .ML sources automatically;
  6544 
  6545   select_equality  -> some_equality
  6546   select_eq_Ex     -> some_eq_ex
  6547   selectI2EX       -> someI2_ex
  6548   selectI2         -> someI2
  6549   selectI          -> someI
  6550   select1_equality -> some1_equality
  6551   Eps_sym_eq       -> some_sym_eq_trivial
  6552   Eps_eq           -> some_eq_trivial
  6553 
  6554 * HOL: exhaust_tac on datatypes superceded by new generic case_tac;
  6555 
  6556 * HOL: removed obsolete theorem binding expand_if (refer to split_if
  6557 instead);
  6558 
  6559 * HOL: the recursion equations generated by 'recdef' are now called
  6560 f.simps instead of f.rules;
  6561 
  6562 * HOL: qed_spec_mp now also handles bounded ALL as well;
  6563 
  6564 * HOL: 0 is now overloaded, so the type constraint ":: nat" may
  6565 sometimes be needed;
  6566 
  6567 * HOL: the constant for "f``x" is now "image" rather than "op ``";
  6568 
  6569 * HOL: the constant for "f-``x" is now "vimage" rather than "op -``";
  6570 
  6571 * HOL: the disjoint sum is now "<+>" instead of "Plus"; the cartesian
  6572 product is now "<*>" instead of "Times"; the lexicographic product is
  6573 now "<*lex*>" instead of "**";
  6574 
  6575 * HOL: theory Sexp is now in HOL/Induct examples (it used to be part
  6576 of main HOL, but was unused); better use HOL's datatype package;
  6577 
  6578 * HOL: removed "symbols" syntax for constant "override" of theory Map;
  6579 the old syntax may be recovered as follows:
  6580 
  6581   syntax (symbols)
  6582     override  :: "('a ~=> 'b) => ('a ~=> 'b) => ('a ~=> 'b)"
  6583       (infixl "\\<oplus>" 100)
  6584 
  6585 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  6586 
  6587 * HOL/ML: even fewer consts are declared as global (see theories Ord,
  6588 Lfp, Gfp, WF); this only affects ML packages that refer to const names
  6589 internally;
  6590 
  6591 * HOL and ZF: syntax for quotienting wrt an equivalence relation
  6592 changed from A/r to A//r;
  6593 
  6594 * ZF: new treatment of arithmetic (nat & int) may break some old
  6595 proofs;
  6596 
  6597 * Isar: renamed some attributes (RS -> THEN, simplify -> simplified,
  6598 rulify -> rule_format, elimify -> elim_format, ...);
  6599 
  6600 * Isar/Provers: intro/elim/dest attributes changed; renamed
  6601 intro/intro!/intro!! flags to intro!/intro/intro? (in most cases, one
  6602 should have to change intro!! to intro? only); replaced "delrule" by
  6603 "rule del";
  6604 
  6605 * Isar/HOL: renamed "intrs" to "intros" in inductive definitions;
  6606 
  6607 * Provers: strengthened force_tac by using new first_best_tac;
  6608 
  6609 * LaTeX document preparation: several changes of isabelle.sty (see
  6610 lib/texinputs);
  6611 
  6612 
  6613 *** Document preparation ***
  6614 
  6615 * formal comments (text blocks etc.) in new-style theories may now
  6616 contain antiquotations of thm/prop/term/typ/text to be presented
  6617 according to latex print mode; concrete syntax is like this:
  6618 @{term[show_types] "f(x) = a + x"};
  6619 
  6620 * isatool mkdir provides easy setup of Isabelle session directories,
  6621 including proper document sources;
  6622 
  6623 * generated LaTeX sources are now deleted after successful run
  6624 (isatool document -c); may retain a copy somewhere else via -D option
  6625 of isatool usedir;
  6626 
  6627 * isatool usedir -D now lets isatool latex -o sty update the Isabelle
  6628 style files, achieving self-contained LaTeX sources and simplifying
  6629 LaTeX debugging;
  6630 
  6631 * old-style theories now produce (crude) LaTeX output as well;
  6632 
  6633 * browser info session directories are now self-contained (may be put
  6634 on WWW server seperately); improved graphs of nested sessions; removed
  6635 graph for 'all sessions';
  6636 
  6637 * several improvements in isabelle style files; \isabellestyle{it}
  6638 produces fake math mode output; \isamarkupheader is now \section by
  6639 default; see lib/texinputs/isabelle.sty etc.;
  6640 
  6641 
  6642 *** Isar ***
  6643 
  6644 * Isar/Pure: local results and corresponding term bindings are now
  6645 subject to Hindley-Milner polymorphism (similar to ML); this
  6646 accommodates incremental type-inference very nicely;
  6647 
  6648 * Isar/Pure: new derived language element 'obtain' supports
  6649 generalized existence reasoning;
  6650 
  6651 * Isar/Pure: new calculational elements 'moreover' and 'ultimately'
  6652 support accumulation of results, without applying any rules yet;
  6653 useful to collect intermediate results without explicit name
  6654 references, and for use with transitivity rules with more than 2
  6655 premises;
  6656 
  6657 * Isar/Pure: scalable support for case-analysis type proofs: new
  6658 'case' language element refers to local contexts symbolically, as
  6659 produced by certain proof methods; internally, case names are attached
  6660 to theorems as "tags";
  6661 
  6662 * Isar/Pure: theory command 'hide' removes declarations from
  6663 class/type/const name spaces;
  6664 
  6665 * Isar/Pure: theory command 'defs' supports option "(overloaded)" to
  6666 indicate potential overloading;
  6667 
  6668 * Isar/Pure: changed syntax of local blocks from {{ }} to { };
  6669 
  6670 * Isar/Pure: syntax of sorts made 'inner', i.e. have to write
  6671 "{a,b,c}" instead of {a,b,c};
  6672 
  6673 * Isar/Pure now provides its own version of intro/elim/dest
  6674 attributes; useful for building new logics, but beware of confusion
  6675 with the version in Provers/classical;
  6676 
  6677 * Isar/Pure: the local context of (non-atomic) goals is provided via
  6678 case name 'antecedent';
  6679 
  6680 * Isar/Pure: removed obsolete 'transfer' attribute (transfer of thms
  6681 to the current context is now done automatically);
  6682 
  6683 * Isar/Pure: theory command 'method_setup' provides a simple interface
  6684 for definining proof methods in ML;
  6685 
  6686 * Isar/Provers: intro/elim/dest attributes changed; renamed
  6687 intro/intro!/intro!! flags to intro!/intro/intro? (INCOMPATIBILITY, in
  6688 most cases, one should have to change intro!! to intro? only);
  6689 replaced "delrule" by "rule del";
  6690 
  6691 * Isar/Provers: new 'hypsubst' method, plain 'subst' method and
  6692 'symmetric' attribute (the latter supercedes [RS sym]);
  6693 
  6694 * Isar/Provers: splitter support (via 'split' attribute and 'simp'
  6695 method modifier); 'simp' method: 'only:' modifier removes loopers as
  6696 well (including splits);
  6697 
  6698 * Isar/Provers: Simplifier and Classical methods now support all kind
  6699 of modifiers used in the past, including 'cong', 'iff', etc.
  6700 
  6701 * Isar/Provers: added 'fastsimp' and 'clarsimp' methods (combination
  6702 of Simplifier and Classical reasoner);
  6703 
  6704 * Isar/HOL: new proof method 'cases' and improved version of 'induct'
  6705 now support named cases; major packages (inductive, datatype, primrec,
  6706 recdef) support case names and properly name parameters;
  6707 
  6708 * Isar/HOL: new transitivity rules for substitution in inequalities --
  6709 monotonicity conditions are extracted to be proven at end of
  6710 calculations;
  6711 
  6712 * Isar/HOL: removed 'case_split' thm binding, should use 'cases' proof
  6713 method anyway;
  6714 
  6715 * Isar/HOL: removed old expand_if = split_if; theorems if_splits =
  6716 split_if split_if_asm; datatype package provides theorems foo.splits =
  6717 foo.split foo.split_asm for each datatype;
  6718 
  6719 * Isar/HOL: tuned inductive package, rename "intrs" to "intros"
  6720 (potential INCOMPATIBILITY), emulation of mk_cases feature for proof
  6721 scripts: new 'inductive_cases' command and 'ind_cases' method; (Note:
  6722 use "(cases (simplified))" method in proper proof texts);
  6723 
  6724 * Isar/HOL: added global 'arith_split' attribute for 'arith' method;
  6725 
  6726 * Isar: names of theorems etc. may be natural numbers as well;
  6727 
  6728 * Isar: 'pr' command: optional arguments for goals_limit and
  6729 ProofContext.prems_limit; no longer prints theory contexts, but only
  6730 proof states;
  6731 
  6732 * Isar: diagnostic commands 'pr', 'thm', 'prop', 'term', 'typ' admit
  6733 additional print modes to be specified; e.g. "pr(latex)" will print
  6734 proof state according to the Isabelle LaTeX style;
  6735 
  6736 * Isar: improved support for emulating tactic scripts, including proof
  6737 methods 'rule_tac' etc., 'cut_tac', 'thin_tac', 'subgoal_tac',
  6738 'rename_tac', 'rotate_tac', 'tactic', and 'case_tac' / 'induct_tac'
  6739 (for HOL datatypes);
  6740 
  6741 * Isar: simplified (more robust) goal selection of proof methods: 1st
  6742 goal, all goals, or explicit goal specifier (tactic emulation); thus
  6743 'proof method scripts' have to be in depth-first order;
  6744 
  6745 * Isar: tuned 'let' syntax: replaced 'as' keyword by 'and';
  6746 
  6747 * Isar: removed 'help' command, which hasn't been too helpful anyway;
  6748 should instead use individual commands for printing items
  6749 (print_commands, print_methods etc.);
  6750 
  6751 * Isar: added 'nothing' --- the empty list of theorems;
  6752 
  6753 
  6754 *** HOL ***
  6755 
  6756 * HOL/MicroJava: formalization of a fragment of Java, together with a
  6757 corresponding virtual machine and a specification of its bytecode
  6758 verifier and a lightweight bytecode verifier, including proofs of
  6759 type-safety; by Gerwin Klein, Tobias Nipkow, David von Oheimb, and
  6760 Cornelia Pusch (see also the homepage of project Bali at
  6761 http://isabelle.in.tum.de/Bali/);
  6762 
  6763 * HOL/Algebra: new theory of rings and univariate polynomials, by
  6764 Clemens Ballarin;
  6765 
  6766 * HOL/NumberTheory: fundamental Theorem of Arithmetic, Chinese
  6767 Remainder Theorem, Fermat/Euler Theorem, Wilson's Theorem, by Thomas M
  6768 Rasmussen;
  6769 
  6770 * HOL/Lattice: fundamental concepts of lattice theory and order
  6771 structures, including duals, properties of bounds versus algebraic
  6772 laws, lattice operations versus set-theoretic ones, the Knaster-Tarski
  6773 Theorem for complete lattices etc.; may also serve as a demonstration
  6774 for abstract algebraic reasoning using axiomatic type classes, and
  6775 mathematics-style proof in Isabelle/Isar; by Markus Wenzel;
  6776 
  6777 * HOL/Prolog: a (bare-bones) implementation of Lambda-Prolog, by David
  6778 von Oheimb;
  6779 
  6780 * HOL/IMPP: extension of IMP with local variables and mutually
  6781 recursive procedures, by David von Oheimb;
  6782 
  6783 * HOL/Lambda: converted into new-style theory and document;
  6784 
  6785 * HOL/ex/Multiquote: example of multiple nested quotations and
  6786 anti-quotations -- basically a generalized version of de-Bruijn
  6787 representation; very useful in avoiding lifting of operations;
  6788 
  6789 * HOL/record: added general record equality rule to simpset; fixed
  6790 select-update simplification procedure to handle extended records as
  6791 well; admit "r" as field name;
  6792 
  6793 * HOL: 0 is now overloaded over the new sort "zero", allowing its use with
  6794 other numeric types and also as the identity of groups, rings, etc.;
  6795 
  6796 * HOL: new axclass plus_ac0 for addition with the AC-laws and 0 as identity.
  6797 Types nat and int belong to this axclass;
  6798 
  6799 * HOL: greatly improved simplification involving numerals of type nat, int, real:
  6800    (i + #8 + j) = Suc k simplifies to  #7 + (i + j) = k
  6801    i*j + k + j*#3*i     simplifies to  #4*(i*j) + k
  6802   two terms #m*u and #n*u are replaced by #(m+n)*u
  6803     (where #m, #n and u can implicitly be 1; this is simproc combine_numerals)
  6804   and the term/formula #m*u+x ~~ #n*u+y simplifies simplifies to #(m-n)+x ~~ y
  6805     or x ~~ #(n-m)+y, where ~~ is one of = < <= or - (simproc cancel_numerals);
  6806 
  6807 * HOL: meson_tac is available (previously in ex/meson.ML); it is a
  6808 powerful prover for predicate logic but knows nothing of clasets; see
  6809 ex/mesontest.ML and ex/mesontest2.ML for example applications;
  6810 
  6811 * HOL: new version of "case_tac" subsumes both boolean case split and
  6812 "exhaust_tac" on datatypes; INCOMPATIBILITY: exhaust_tac no longer
  6813 exists, may define val exhaust_tac = case_tac for ad-hoc portability;
  6814 
  6815 * HOL: simplification no longer dives into case-expressions: only the
  6816 selector expression is simplified, but not the remaining arms; to
  6817 enable full simplification of case-expressions for datatype t, you may
  6818 remove t.weak_case_cong from the simpset, either globally (Delcongs
  6819 [thm"t.weak_case_cong"];) or locally (delcongs [...]).
  6820 
  6821 * HOL/recdef: the recursion equations generated by 'recdef' for
  6822 function 'f' are now called f.simps instead of f.rules; if all
  6823 termination conditions are proved automatically, these simplification
  6824 rules are added to the simpset, as in primrec; rules may be named
  6825 individually as well, resulting in a separate list of theorems for
  6826 each equation;
  6827 
  6828 * HOL/While is a new theory that provides a while-combinator. It
  6829 permits the definition of tail-recursive functions without the
  6830 provision of a termination measure. The latter is necessary once the
  6831 invariant proof rule for while is applied.
  6832 
  6833 * HOL: new (overloaded) notation for the set of elements below/above
  6834 some element: {..u}, {..u(}, {l..}, {)l..}. See theory SetInterval.
  6835 
  6836 * HOL: theorems impI, allI, ballI bound as "strip";
  6837 
  6838 * HOL: new tactic induct_thm_tac: thm -> string -> int -> tactic
  6839 induct_tac th "x1 ... xn" expects th to have a conclusion of the form
  6840 P v1 ... vn and abbreviates res_inst_tac [("v1","x1"),...,("vn","xn")] th;
  6841 
  6842 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  6843 
  6844 * HOL: theory Sexp now in HOL/Induct examples (it used to be part of
  6845 main HOL, but was unused);
  6846 
  6847 * HOL: fewer consts declared as global (e.g. have to refer to
  6848 "Lfp.lfp" instead of "lfp" internally; affects ML packages only);
  6849 
  6850 * HOL: tuned AST representation of nested pairs, avoiding bogus output
  6851 in case of overlap with user translations (e.g. judgements over
  6852 tuples); (note that the underlying logical represenation is still
  6853 bogus);
  6854 
  6855 
  6856 *** ZF ***
  6857 
  6858 * ZF: simplification automatically cancels common terms in arithmetic
  6859 expressions over nat and int;
  6860 
  6861 * ZF: new treatment of nat to minimize type-checking: all operators
  6862 coerce their operands to a natural number using the function natify,
  6863 making the algebraic laws unconditional;
  6864 
  6865 * ZF: as above, for int: operators coerce their operands to an integer
  6866 using the function intify;
  6867 
  6868 * ZF: the integer library now contains many of the usual laws for the
  6869 orderings, including $<=, and monotonicity laws for $+ and $*;
  6870 
  6871 * ZF: new example ZF/ex/NatSum to demonstrate integer arithmetic
  6872 simplification;
  6873 
  6874 * FOL and ZF: AddIffs now available, giving theorems of the form P<->Q
  6875 to the simplifier and classical reasoner simultaneously;
  6876 
  6877 
  6878 *** General ***
  6879 
  6880 * Provers: blast_tac now handles actual object-logic rules as
  6881 assumptions; note that auto_tac uses blast_tac internally as well;
  6882 
  6883 * Provers: new functions rulify/rulify_no_asm: thm -> thm for turning
  6884 outer -->/All/Ball into ==>/!!; qed_spec_mp now uses rulify_no_asm;
  6885 
  6886 * Provers: delrules now handles destruct rules as well (no longer need
  6887 explicit make_elim);
  6888 
  6889 * Provers: Blast_tac now warns of and ignores "weak elimination rules" e.g.
  6890   [| inj ?f;          ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
  6891 use instead the strong form,
  6892   [| inj ?f; ~ ?W ==> ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
  6893 in HOL, FOL and ZF the function cla_make_elim will create such rules
  6894 from destruct-rules;
  6895 
  6896 * Provers: Simplifier.easy_setup provides a fast path to basic
  6897 Simplifier setup for new object-logics;
  6898 
  6899 * Pure: AST translation rules no longer require constant head on LHS;
  6900 
  6901 * Pure: improved name spaces: ambiguous output is qualified; support
  6902 for hiding of names;
  6903 
  6904 * system: smart setup of canonical ML_HOME, ISABELLE_INTERFACE, and
  6905 XSYMBOL_HOME; no longer need to do manual configuration in most
  6906 situations;
  6907 
  6908 * system: compression of ML heaps images may now be controlled via -c
  6909 option of isabelle and isatool usedir (currently only observed by
  6910 Poly/ML);
  6911 
  6912 * system: isatool installfonts may handle X-Symbol fonts as well (very
  6913 useful for remote X11);
  6914 
  6915 * system: provide TAGS file for Isabelle sources;
  6916 
  6917 * ML: infix 'OF' is a version of 'MRS' with more appropriate argument
  6918 order;
  6919 
  6920 * ML: renamed flags Syntax.trace_norm_ast to Syntax.trace_ast; global
  6921 timing flag supersedes proof_timing and Toplevel.trace;
  6922 
  6923 * ML: new combinators |>> and |>>> for incremental transformations
  6924 with secondary results (e.g. certain theory extensions):
  6925 
  6926 * ML: PureThy.add_defs gets additional argument to indicate potential
  6927 overloading (usually false);
  6928 
  6929 * ML: PureThy.add_thms/add_axioms/add_defs now return theorems as
  6930 results;
  6931 
  6932 
  6933 
  6934 New in Isabelle99 (October 1999)
  6935 --------------------------------
  6936 
  6937 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  6938 
  6939 * HOL: The THEN and ELSE parts of conditional expressions (if P then x else y)
  6940 are no longer simplified.  (This allows the simplifier to unfold recursive
  6941 functional programs.)  To restore the old behaviour, declare
  6942 
  6943     Delcongs [if_weak_cong];
  6944 
  6945 * HOL: Removed the obsolete syntax "Compl A"; use -A for set
  6946 complement;
  6947 
  6948 * HOL: the predicate "inj" is now defined by translation to "inj_on";
  6949 
  6950 * HOL/datatype: mutual_induct_tac no longer exists --
  6951   use induct_tac "x_1 ... x_n" instead of mutual_induct_tac ["x_1", ..., "x_n"]
  6952 
  6953 * HOL/typedef: fixed type inference for representing set; type
  6954 arguments now have to occur explicitly on the rhs as type constraints;
  6955 
  6956 * ZF: The con_defs part of an inductive definition may no longer refer
  6957 to constants declared in the same theory;
  6958 
  6959 * HOL, ZF: the function mk_cases, generated by the inductive
  6960 definition package, has lost an argument.  To simplify its result, it
  6961 uses the default simpset instead of a supplied list of theorems.
  6962 
  6963 * HOL/List: the constructors of type list are now Nil and Cons;
  6964 
  6965 * Simplifier: the type of the infix ML functions
  6966         setSSolver addSSolver setSolver addSolver
  6967 is now  simpset * solver -> simpset  where `solver' is a new abstract type
  6968 for packaging solvers. A solver is created via
  6969         mk_solver: string -> (thm list -> int -> tactic) -> solver
  6970 where the string argument is only a comment.
  6971 
  6972 
  6973 *** Proof tools ***
  6974 
  6975 * Provers/Arith/fast_lin_arith.ML contains a functor for creating a
  6976 decision procedure for linear arithmetic. Currently it is used for
  6977 types `nat', `int', and `real' in HOL (see below); it can, should and
  6978 will be instantiated for other types and logics as well.
  6979 
  6980 * The simplifier now accepts rewrite rules with flexible heads, eg
  6981      hom ?f ==> ?f(?x+?y) = ?f ?x + ?f ?y
  6982   They are applied like any rule with a non-pattern lhs, i.e. by first-order
  6983   matching.
  6984 
  6985 
  6986 *** General ***
  6987 
  6988 * New Isabelle/Isar subsystem provides an alternative to traditional
  6989 tactical theorem proving; together with the ProofGeneral/isar user
  6990 interface it offers an interactive environment for developing human
  6991 readable proof documents (Isar == Intelligible semi-automated
  6992 reasoning); for further information see isatool doc isar-ref,
  6993 src/HOL/Isar_examples and http://isabelle.in.tum.de/Isar/
  6994 
  6995 * improved and simplified presentation of theories: better HTML markup
  6996 (including colors), graph views in several sizes; isatool usedir now
  6997 provides a proper interface for user theories (via -P option); actual
  6998 document preparation based on (PDF)LaTeX is available as well (for
  6999 new-style theories only); see isatool doc system for more information;
  7000 
  7001 * native support for Proof General, both for classic Isabelle and
  7002 Isabelle/Isar;
  7003 
  7004 * ML function thm_deps visualizes dependencies of theorems and lemmas,
  7005 using the graph browser tool;
  7006 
  7007 * Isabelle manuals now also available as PDF;
  7008 
  7009 * theory loader rewritten from scratch (may not be fully
  7010 bug-compatible); old loadpath variable has been replaced by show_path,
  7011 add_path, del_path, reset_path functions; new operations such as
  7012 update_thy, touch_thy, remove_thy, use/update_thy_only (see also
  7013 isatool doc ref);
  7014 
  7015 * improved isatool install: option -k creates KDE application icon,
  7016 option -p DIR installs standalone binaries;
  7017 
  7018 * added ML_PLATFORM setting (useful for cross-platform installations);
  7019 more robust handling of platform specific ML images for SML/NJ;
  7020 
  7021 * the settings environment is now statically scoped, i.e. it is never
  7022 created again in sub-processes invoked from isabelle, isatool, or
  7023 Isabelle;
  7024 
  7025 * path element specification '~~' refers to '$ISABELLE_HOME';
  7026 
  7027 * in locales, the "assumes" and "defines" parts may be omitted if
  7028 empty;
  7029 
  7030 * new print_mode "xsymbols" for extended symbol support (e.g. genuine
  7031 long arrows);
  7032 
  7033 * new print_mode "HTML";
  7034 
  7035 * new flag show_tags controls display of tags of theorems (which are
  7036 basically just comments that may be attached by some tools);
  7037 
  7038 * Isamode 2.6 requires patch to accomodate change of Isabelle font
  7039 mode and goal output format:
  7040 
  7041 diff -r Isamode-2.6/elisp/isa-load.el Isamode/elisp/isa-load.el
  7042 244c244
  7043 <       (list (isa-getenv "ISABELLE") "-msymbols" logic-name)
  7044 ---
  7045 >       (list (isa-getenv "ISABELLE") "-misabelle_font" "-msymbols" logic-name)
  7046 diff -r Isabelle-2.6/elisp/isa-proofstate.el Isamode/elisp/isa-proofstate.el
  7047 181c181
  7048 < (defconst proofstate-proofstart-regexp "^Level [0-9]+$"
  7049 ---
  7050 > (defconst proofstate-proofstart-regexp "^Level [0-9]+"
  7051 
  7052 * function bind_thms stores lists of theorems (cf. bind_thm);
  7053 
  7054 * new shorthand tactics ftac, eatac, datac, fatac;
  7055 
  7056 * qed (and friends) now accept "" as result name; in that case the
  7057 theorem is not stored, but proper checks and presentation of the
  7058 result still apply;
  7059 
  7060 * theorem database now also indexes constants "Trueprop", "all",
  7061 "==>", "=="; thus thms_containing, findI etc. may retrieve more rules;
  7062 
  7063 
  7064 *** HOL ***
  7065 
  7066 ** HOL arithmetic **
  7067 
  7068 * There are now decision procedures for linear arithmetic over nat and
  7069 int:
  7070 
  7071 1. arith_tac copes with arbitrary formulae involving `=', `<', `<=',
  7072 `+', `-', `Suc', `min', `max' and numerical constants; other subterms
  7073 are treated as atomic; subformulae not involving type `nat' or `int'
  7074 are ignored; quantified subformulae are ignored unless they are
  7075 positive universal or negative existential. The tactic has to be
  7076 invoked by hand and can be a little bit slow. In particular, the
  7077 running time is exponential in the number of occurrences of `min' and
  7078 `max', and `-' on `nat'.
  7079 
  7080 2. fast_arith_tac is a cut-down version of arith_tac: it only takes
  7081 (negated) (in)equalities among the premises and the conclusion into
  7082 account (i.e. no compound formulae) and does not know about `min' and
  7083 `max', and `-' on `nat'. It is fast and is used automatically by the
  7084 simplifier.
  7085 
  7086 NB: At the moment, these decision procedures do not cope with mixed
  7087 nat/int formulae where the two parts interact, such as `m < n ==>
  7088 int(m) < int(n)'.
  7089 
  7090 * HOL/Numeral provides a generic theory of numerals (encoded
  7091 efficiently as bit strings); setup for types nat/int/real is in place;
  7092 INCOMPATIBILITY: since numeral syntax is now polymorphic, rather than
  7093 int, existing theories and proof scripts may require a few additional
  7094 type constraints;
  7095 
  7096 * integer division and remainder can now be performed on constant
  7097 arguments;
  7098 
  7099 * many properties of integer multiplication, division and remainder
  7100 are now available;
  7101 
  7102 * An interface to the Stanford Validity Checker (SVC) is available through the
  7103 tactic svc_tac.  Propositional tautologies and theorems of linear arithmetic
  7104 are proved automatically.  SVC must be installed separately, and its results
  7105 must be TAKEN ON TRUST (Isabelle does not check the proofs, but tags any
  7106 invocation of the underlying oracle).  For SVC see
  7107   http://verify.stanford.edu/SVC
  7108 
  7109 * IsaMakefile: the HOL-Real target now builds an actual image;
  7110 
  7111 
  7112 ** HOL misc **
  7113 
  7114 * HOL/Real/HahnBanach: the Hahn-Banach theorem for real vector spaces
  7115 (in Isabelle/Isar) -- by Gertrud Bauer;
  7116 
  7117 * HOL/BCV: generic model of bytecode verification, i.e. data-flow
  7118 analysis for assembly languages with subtypes;
  7119 
  7120 * HOL/TLA (Lamport's Temporal Logic of Actions): major reorganization
  7121 -- avoids syntactic ambiguities and treats state, transition, and
  7122 temporal levels more uniformly; introduces INCOMPATIBILITIES due to
  7123 changed syntax and (many) tactics;
  7124 
  7125 * HOL/inductive: Now also handles more general introduction rules such
  7126   as "ALL y. (y, x) : r --> y : acc r ==> x : acc r"; monotonicity
  7127   theorems are now maintained within the theory (maintained via the
  7128   "mono" attribute);
  7129 
  7130 * HOL/datatype: Now also handles arbitrarily branching datatypes
  7131   (using function types) such as
  7132 
  7133   datatype 'a tree = Atom 'a | Branch "nat => 'a tree"
  7134 
  7135 * HOL/record: record_simproc (part of the default simpset) takes care
  7136 of selectors applied to updated records; record_split_tac is no longer
  7137 part of the default claset; update_defs may now be removed from the
  7138 simpset in many cases; COMPATIBILITY: old behavior achieved by
  7139 
  7140   claset_ref () := claset() addSWrapper record_split_wrapper;
  7141   Delsimprocs [record_simproc]
  7142 
  7143 * HOL/typedef: fixed type inference for representing set; type
  7144 arguments now have to occur explicitly on the rhs as type constraints;
  7145 
  7146 * HOL/recdef (TFL): 'congs' syntax now expects comma separated list of theorem
  7147 names rather than an ML expression;
  7148 
  7149 * HOL/defer_recdef (TFL): like recdef but the well-founded relation can be
  7150 supplied later.  Program schemes can be defined, such as
  7151     "While B C s = (if B s then While B C (C s) else s)"
  7152 where the well-founded relation can be chosen after B and C have been given.
  7153 
  7154 * HOL/List: the constructors of type list are now Nil and Cons;
  7155 INCOMPATIBILITY: while [] and infix # syntax is still there, of
  7156 course, ML tools referring to List.list.op # etc. have to be adapted;
  7157 
  7158 * HOL_quantifiers flag superseded by "HOL" print mode, which is
  7159 disabled by default; run isabelle with option -m HOL to get back to
  7160 the original Gordon/HOL-style output;
  7161 
  7162 * HOL/Ord.thy: new bounded quantifier syntax (input only): ALL x<y. P,
  7163 ALL x<=y. P, EX x<y. P, EX x<=y. P;
  7164 
  7165 * HOL basic syntax simplified (more orthogonal): all variants of
  7166 All/Ex now support plain / symbolic / HOL notation; plain syntax for
  7167 Eps operator is provided as well: "SOME x. P[x]";
  7168 
  7169 * HOL/Sum.thy: sum_case has been moved to HOL/Datatype;
  7170 
  7171 * HOL/Univ.thy: infix syntax <*>, <+>, <**>, <+> eliminated and made
  7172 thus available for user theories;
  7173 
  7174 * HOLCF/IOA/Sequents: renamed 'Cons' to 'Consq' to avoid clash with
  7175 HOL/List; hardly an INCOMPATIBILITY since '>>' syntax is used all the
  7176 time;
  7177 
  7178 * HOL: new tactic smp_tac: int -> int -> tactic, which applies spec
  7179 several times and then mp;
  7180 
  7181 
  7182 *** LK ***
  7183 
  7184 * the notation <<...>> is now available as a notation for sequences of
  7185 formulas;
  7186 
  7187 * the simplifier is now installed
  7188 
  7189 * the axiom system has been generalized (thanks to Soren Heilmann)
  7190 
  7191 * the classical reasoner now has a default rule database
  7192 
  7193 
  7194 *** ZF ***
  7195 
  7196 * new primrec section allows primitive recursive functions to be given
  7197 directly (as in HOL) over datatypes and the natural numbers;
  7198 
  7199 * new tactics induct_tac and exhaust_tac for induction (or case
  7200 analysis) over datatypes and the natural numbers;
  7201 
  7202 * the datatype declaration of type T now defines the recursor T_rec;
  7203 
  7204 * simplification automatically does freeness reasoning for datatype
  7205 constructors;
  7206 
  7207 * automatic type-inference, with AddTCs command to insert new
  7208 type-checking rules;
  7209 
  7210 * datatype introduction rules are now added as Safe Introduction rules
  7211 to the claset;
  7212 
  7213 * the syntax "if P then x else y" is now available in addition to
  7214 if(P,x,y);
  7215 
  7216 
  7217 *** Internal programming interfaces ***
  7218 
  7219 * tuned simplifier trace output; new flag debug_simp;
  7220 
  7221 * structures Vartab / Termtab (instances of TableFun) offer efficient
  7222 tables indexed by indexname_ord / term_ord (compatible with aconv);
  7223 
  7224 * AxClass.axclass_tac lost the theory argument;
  7225 
  7226 * tuned current_goals_markers semantics: begin / end goal avoids
  7227 printing empty lines;
  7228 
  7229 * removed prs and prs_fn hook, which was broken because it did not
  7230 include \n in its semantics, forcing writeln to add one
  7231 uncoditionally; replaced prs_fn by writeln_fn; consider std_output:
  7232 string -> unit if you really want to output text without newline;
  7233 
  7234 * Symbol.output subject to print mode; INCOMPATIBILITY: defaults to
  7235 plain output, interface builders may have to enable 'isabelle_font'
  7236 mode to get Isabelle font glyphs as before;
  7237 
  7238 * refined token_translation interface; INCOMPATIBILITY: output length
  7239 now of type real instead of int;
  7240 
  7241 * theory loader actions may be traced via new ThyInfo.add_hook
  7242 interface (see src/Pure/Thy/thy_info.ML); example application: keep
  7243 your own database of information attached to *whole* theories -- as
  7244 opposed to intra-theory data slots offered via TheoryDataFun;
  7245 
  7246 * proper handling of dangling sort hypotheses (at last!);
  7247 Thm.strip_shyps and Drule.strip_shyps_warning take care of removing
  7248 extra sort hypotheses that can be witnessed from the type signature;
  7249 the force_strip_shyps flag is gone, any remaining shyps are simply
  7250 left in the theorem (with a warning issued by strip_shyps_warning);
  7251 
  7252 
  7253 
  7254 New in Isabelle98-1 (October 1998)
  7255 ----------------------------------
  7256 
  7257 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  7258 
  7259 * several changes of automated proof tools;
  7260 
  7261 * HOL: major changes to the inductive and datatype packages, including
  7262 some minor incompatibilities of theory syntax;
  7263 
  7264 * HOL: renamed r^-1 to 'converse' from 'inverse'; 'inj_onto' is now
  7265 called `inj_on';
  7266 
  7267 * HOL: removed duplicate thms in Arith:
  7268   less_imp_add_less  should be replaced by  trans_less_add1
  7269   le_imp_add_le      should be replaced by  trans_le_add1
  7270 
  7271 * HOL: unary minus is now overloaded (new type constraints may be
  7272 required);
  7273 
  7274 * HOL and ZF: unary minus for integers is now #- instead of #~.  In
  7275 ZF, expressions such as n#-1 must be changed to n#- 1, since #-1 is
  7276 now taken as an integer constant.
  7277 
  7278 * Pure: ML function 'theory_of' renamed to 'theory';
  7279 
  7280 
  7281 *** Proof tools ***
  7282 
  7283 * Simplifier:
  7284   1. Asm_full_simp_tac is now more aggressive.
  7285      1. It will sometimes reorient premises if that increases their power to
  7286         simplify.
  7287      2. It does no longer proceed strictly from left to right but may also
  7288         rotate premises to achieve further simplification.
  7289      For compatibility reasons there is now Asm_lr_simp_tac which is like the
  7290      old Asm_full_simp_tac in that it does not rotate premises.
  7291   2. The simplifier now knows a little bit about nat-arithmetic.
  7292 
  7293 * Classical reasoner: wrapper mechanism for the classical reasoner now
  7294 allows for selected deletion of wrappers, by introduction of names for
  7295 wrapper functionals.  This implies that addbefore, addSbefore,
  7296 addaltern, and addSaltern now take a pair (name, tactic) as argument,
  7297 and that adding two tactics with the same name overwrites the first
  7298 one (emitting a warning).
  7299   type wrapper = (int -> tactic) -> (int -> tactic)
  7300   setWrapper, setSWrapper, compWrapper and compSWrapper are replaced by
  7301   addWrapper, addSWrapper: claset * (string * wrapper) -> claset
  7302   delWrapper, delSWrapper: claset *  string            -> claset
  7303   getWrapper is renamed to appWrappers, getSWrapper to appSWrappers;
  7304 
  7305 * Classical reasoner: addbefore/addSbefore now have APPEND/ORELSE
  7306 semantics; addbefore now affects only the unsafe part of step_tac
  7307 etc.; this affects addss/auto_tac/force_tac, so EXISTING PROOFS MAY
  7308 FAIL, but proofs should be fixable easily, e.g. by replacing Auto_tac
  7309 by Force_tac;
  7310 
  7311 * Classical reasoner: setwrapper to setWrapper and compwrapper to
  7312 compWrapper; added safe wrapper (and access functions for it);
  7313 
  7314 * HOL/split_all_tac is now much faster and fails if there is nothing
  7315 to split.  Some EXISTING PROOFS MAY REQUIRE ADAPTION because the order
  7316 and the names of the automatically generated variables have changed.
  7317 split_all_tac has moved within claset() from unsafe wrappers to safe
  7318 wrappers, which means that !!-bound variables are split much more
  7319 aggressively, and safe_tac and clarify_tac now split such variables.
  7320 If this splitting is not appropriate, use delSWrapper "split_all_tac".
  7321 Note: the same holds for record_split_tac, which does the job of
  7322 split_all_tac for record fields.
  7323 
  7324 * HOL/Simplifier: Rewrite rules for case distinctions can now be added
  7325 permanently to the default simpset using Addsplits just like
  7326 Addsimps. They can be removed via Delsplits just like
  7327 Delsimps. Lower-case versions are also available.
  7328 
  7329 * HOL/Simplifier: The rule split_if is now part of the default
  7330 simpset. This means that the simplifier will eliminate all occurrences
  7331 of if-then-else in the conclusion of a goal. To prevent this, you can
  7332 either remove split_if completely from the default simpset by
  7333 `Delsplits [split_if]' or remove it in a specific call of the
  7334 simplifier using `... delsplits [split_if]'.  You can also add/delete
  7335 other case splitting rules to/from the default simpset: every datatype
  7336 generates suitable rules `split_t_case' and `split_t_case_asm' (where
  7337 t is the name of the datatype).
  7338 
  7339 * Classical reasoner / Simplifier combination: new force_tac (and
  7340 derivatives Force_tac, force) combines rewriting and classical
  7341 reasoning (and whatever other tools) similarly to auto_tac, but is
  7342 aimed to solve the given subgoal completely.
  7343 
  7344 
  7345 *** General ***
  7346 
  7347 * new top-level commands `Goal' and `Goalw' that improve upon `goal'
  7348 and `goalw': the theory is no longer needed as an explicit argument -
  7349 the current theory context is used; assumptions are no longer returned
  7350 at the ML-level unless one of them starts with ==> or !!; it is
  7351 recommended to convert to these new commands using isatool fixgoal
  7352 (backup your sources first!);
  7353 
  7354 * new top-level commands 'thm' and 'thms' for retrieving theorems from
  7355 the current theory context, and 'theory' to lookup stored theories;
  7356 
  7357 * new theory section 'locale' for declaring constants, assumptions and
  7358 definitions that have local scope;
  7359 
  7360 * new theory section 'nonterminals' for purely syntactic types;
  7361 
  7362 * new theory section 'setup' for generic ML setup functions
  7363 (e.g. package initialization);
  7364 
  7365 * the distribution now includes Isabelle icons: see
  7366 lib/logo/isabelle-{small,tiny}.xpm;
  7367 
  7368 * isatool install - install binaries with absolute references to
  7369 ISABELLE_HOME/bin;
  7370 
  7371 * isatool logo -- create instances of the Isabelle logo (as EPS);
  7372 
  7373 * print mode 'emacs' reserved for Isamode;
  7374 
  7375 * support multiple print (ast) translations per constant name;
  7376 
  7377 * theorems involving oracles are now printed with a suffixed [!];
  7378 
  7379 
  7380 *** HOL ***
  7381 
  7382 * there is now a tutorial on Isabelle/HOL (do 'isatool doc tutorial');
  7383 
  7384 * HOL/inductive package reorganized and improved: now supports mutual
  7385 definitions such as
  7386 
  7387   inductive EVEN ODD
  7388     intrs
  7389       null "0 : EVEN"
  7390       oddI "n : EVEN ==> Suc n : ODD"
  7391       evenI "n : ODD ==> Suc n : EVEN"
  7392 
  7393 new theorem list "elims" contains an elimination rule for each of the
  7394 recursive sets; inductive definitions now handle disjunctive premises
  7395 correctly (also ZF);
  7396 
  7397 INCOMPATIBILITIES: requires Inductive as an ancestor; component
  7398 "mutual_induct" no longer exists - the induction rule is always
  7399 contained in "induct";
  7400 
  7401 
  7402 * HOL/datatype package re-implemented and greatly improved: now
  7403 supports mutually recursive datatypes such as
  7404 
  7405   datatype
  7406     'a aexp = IF_THEN_ELSE ('a bexp) ('a aexp) ('a aexp)
  7407             | SUM ('a aexp) ('a aexp)
  7408             | DIFF ('a aexp) ('a aexp)
  7409             | NUM 'a
  7410   and
  7411     'a bexp = LESS ('a aexp) ('a aexp)
  7412             | AND ('a bexp) ('a bexp)
  7413             | OR ('a bexp) ('a bexp)
  7414 
  7415 as well as indirectly recursive datatypes such as
  7416 
  7417   datatype
  7418     ('a, 'b) term = Var 'a
  7419                   | App 'b ((('a, 'b) term) list)
  7420 
  7421 The new tactic  mutual_induct_tac [<var_1>, ..., <var_n>] i  performs
  7422 induction on mutually / indirectly recursive datatypes.
  7423 
  7424 Primrec equations are now stored in theory and can be accessed via
  7425 <function_name>.simps.
  7426 
  7427 INCOMPATIBILITIES:
  7428 
  7429   - Theories using datatypes must now have theory Datatype as an
  7430     ancestor.
  7431   - The specific <typename>.induct_tac no longer exists - use the
  7432     generic induct_tac instead.
  7433   - natE has been renamed to nat.exhaust - use exhaust_tac
  7434     instead of res_inst_tac ... natE. Note that the variable
  7435     names in nat.exhaust differ from the names in natE, this
  7436     may cause some "fragile" proofs to fail.
  7437   - The theorems split_<typename>_case and split_<typename>_case_asm
  7438     have been renamed to <typename>.split and <typename>.split_asm.
  7439   - Since default sorts of type variables are now handled correctly,
  7440     some datatype definitions may have to be annotated with explicit
  7441     sort constraints.
  7442   - Primrec definitions no longer require function name and type
  7443     of recursive argument.
  7444 
  7445 Consider using isatool fixdatatype to adapt your theories and proof
  7446 scripts to the new package (backup your sources first!).
  7447 
  7448 
  7449 * HOL/record package: considerably improved implementation; now
  7450 includes concrete syntax for record types, terms, updates; theorems
  7451 for surjective pairing and splitting !!-bound record variables; proof
  7452 support is as follows:
  7453 
  7454   1) standard conversions (selectors or updates applied to record
  7455 constructor terms) are part of the standard simpset;
  7456 
  7457   2) inject equations of the form ((x, y) = (x', y')) == x=x' & y=y' are
  7458 made part of standard simpset and claset via addIffs;
  7459 
  7460   3) a tactic for record field splitting (record_split_tac) is part of
  7461 the standard claset (addSWrapper);
  7462 
  7463 To get a better idea about these rules you may retrieve them via
  7464 something like 'thms "foo.simps"' or 'thms "foo.iffs"', where "foo" is
  7465 the name of your record type.
  7466 
  7467 The split tactic 3) conceptually simplifies by the following rule:
  7468 
  7469   "(!!x. PROP ?P x) == (!!a b. PROP ?P (a, b))"
  7470 
  7471 Thus any record variable that is bound by meta-all will automatically
  7472 blow up into some record constructor term, consequently the
  7473 simplifications of 1), 2) apply.  Thus force_tac, auto_tac etc. shall
  7474 solve record problems automatically.
  7475 
  7476 
  7477 * reorganized the main HOL image: HOL/Integ and String loaded by
  7478 default; theory Main includes everything;
  7479 
  7480 * automatic simplification of integer sums and comparisons, using cancellation;
  7481 
  7482 * added option_map_eq_Some and not_Some_eq to the default simpset and claset;
  7483 
  7484 * added disj_not1 = "(~P | Q) = (P --> Q)" to the default simpset;
  7485 
  7486 * many new identities for unions, intersections, set difference, etc.;
  7487 
  7488 * expand_if, expand_split, expand_sum_case and expand_nat_case are now
  7489 called split_if, split_split, split_sum_case and split_nat_case (to go
  7490 with add/delsplits);
  7491 
  7492 * HOL/Prod introduces simplification procedure unit_eq_proc rewriting
  7493 (?x::unit) = (); this is made part of the default simpset, which COULD
  7494 MAKE EXISTING PROOFS FAIL under rare circumstances (consider
  7495 'Delsimprocs [unit_eq_proc];' as last resort); also note that
  7496 unit_abs_eta_conv is added in order to counter the effect of
  7497 unit_eq_proc on (%u::unit. f u), replacing it by f rather than by
  7498 %u.f();
  7499 
  7500 * HOL/Fun INCOMPATIBILITY: `inj_onto' is now called `inj_on' (which
  7501 makes more sense);
  7502 
  7503 * HOL/Set INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
  7504   It and 'sym RS equals0D' are now in the default  claset, giving automatic
  7505   disjointness reasoning but breaking a few old proofs.
  7506 
  7507 * HOL/Relation INCOMPATIBILITY: renamed the relational operator r^-1
  7508 to 'converse' from 'inverse' (for compatibility with ZF and some
  7509 literature);
  7510 
  7511 * HOL/recdef can now declare non-recursive functions, with {} supplied as
  7512 the well-founded relation;
  7513 
  7514 * HOL/Set INCOMPATIBILITY: the complement of set A is now written -A instead of
  7515     Compl A.  The "Compl" syntax remains available as input syntax for this
  7516     release ONLY.
  7517 
  7518 * HOL/Update: new theory of function updates:
  7519     f(a:=b) == %x. if x=a then b else f x
  7520 may also be iterated as in f(a:=b,c:=d,...);
  7521 
  7522 * HOL/Vimage: new theory for inverse image of a function, syntax f-``B;
  7523 
  7524 * HOL/List:
  7525   - new function list_update written xs[i:=v] that updates the i-th
  7526     list position. May also be iterated as in xs[i:=a,j:=b,...].
  7527   - new function `upt' written [i..j(] which generates the list
  7528     [i,i+1,...,j-1], i.e. the upper bound is excluded. To include the upper
  7529     bound write [i..j], which is a shorthand for [i..j+1(].
  7530   - new lexicographic orderings and corresponding wellfoundedness theorems.
  7531 
  7532 * HOL/Arith:
  7533   - removed 'pred' (predecessor) function;
  7534   - generalized some theorems about n-1;
  7535   - many new laws about "div" and "mod";
  7536   - new laws about greatest common divisors (see theory ex/Primes);
  7537 
  7538 * HOL/Relation: renamed the relational operator r^-1 "converse"
  7539 instead of "inverse";
  7540 
  7541 * HOL/Induct/Multiset: a theory of multisets, including the wellfoundedness
  7542   of the multiset ordering;
  7543 
  7544 * directory HOL/Real: a construction of the reals using Dedekind cuts
  7545   (not included by default);
  7546 
  7547 * directory HOL/UNITY: Chandy and Misra's UNITY formalism;
  7548 
  7549 * directory HOL/Hoare: a new version of Hoare logic which permits many-sorted
  7550   programs, i.e. different program variables may have different types.
  7551 
  7552 * calling (stac rew i) now fails if "rew" has no effect on the goal
  7553   [previously, this check worked only if the rewrite rule was unconditional]
  7554   Now rew can involve either definitions or equalities (either == or =).
  7555 
  7556 
  7557 *** ZF ***
  7558 
  7559 * theory Main includes everything; INCOMPATIBILITY: theory ZF.thy contains
  7560   only the theorems proved on ZF.ML;
  7561 
  7562 * ZF INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
  7563   It and 'sym RS equals0D' are now in the default  claset, giving automatic
  7564   disjointness reasoning but breaking a few old proofs.
  7565 
  7566 * ZF/Update: new theory of function updates
  7567     with default rewrite rule  f(x:=y) ` z = if(z=x, y, f`z)
  7568   may also be iterated as in f(a:=b,c:=d,...);
  7569 
  7570 * in  let x=t in u(x), neither t nor u(x) has to be an FOL term.
  7571 
  7572 * calling (stac rew i) now fails if "rew" has no effect on the goal
  7573   [previously, this check worked only if the rewrite rule was unconditional]
  7574   Now rew can involve either definitions or equalities (either == or =).
  7575 
  7576 * case_tac provided for compatibility with HOL
  7577     (like the old excluded_middle_tac, but with subgoals swapped)
  7578 
  7579 
  7580 *** Internal programming interfaces ***
  7581 
  7582 * Pure: several new basic modules made available for general use, see
  7583 also src/Pure/README;
  7584 
  7585 * improved the theory data mechanism to support encapsulation (data
  7586 kind name replaced by private Object.kind, acting as authorization
  7587 key); new type-safe user interface via functor TheoryDataFun; generic
  7588 print_data function becomes basically useless;
  7589 
  7590 * removed global_names compatibility flag -- all theory declarations
  7591 are qualified by default;
  7592 
  7593 * module Pure/Syntax now offers quote / antiquote translation
  7594 functions (useful for Hoare logic etc. with implicit dependencies);
  7595 see HOL/ex/Antiquote for an example use;
  7596 
  7597 * Simplifier now offers conversions (asm_)(full_)rewrite: simpset ->
  7598 cterm -> thm;
  7599 
  7600 * new tactical CHANGED_GOAL for checking that a tactic modifies a
  7601 subgoal;
  7602 
  7603 * Display.print_goals function moved to Locale.print_goals;
  7604 
  7605 * standard print function for goals supports current_goals_markers
  7606 variable for marking begin of proof, end of proof, start of goal; the
  7607 default is ("", "", ""); setting current_goals_markers := ("<proof>",
  7608 "</proof>", "<goal>") causes SGML like tagged proof state printing,
  7609 for example;
  7610 
  7611 
  7612 
  7613 New in Isabelle98 (January 1998)
  7614 --------------------------------
  7615 
  7616 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  7617 
  7618 * changed lexical syntax of terms / types: dots made part of long
  7619 identifiers, e.g. "%x.x" no longer possible, should be "%x. x";
  7620 
  7621 * simpset (and claset) reference variable replaced by functions
  7622 simpset / simpset_ref;
  7623 
  7624 * no longer supports theory aliases (via merge) and non-trivial
  7625 implicit merge of thms' signatures;
  7626 
  7627 * most internal names of constants changed due to qualified names;
  7628 
  7629 * changed Pure/Sequence interface (see Pure/seq.ML);
  7630 
  7631 
  7632 *** General Changes ***
  7633 
  7634 * hierachically structured name spaces (for consts, types, axms, thms
  7635 etc.); new lexical class 'longid' (e.g. Foo.bar.x) may render much of
  7636 old input syntactically incorrect (e.g. "%x.x"); COMPATIBILITY:
  7637 isatool fixdots ensures space after dots (e.g. "%x. x"); set
  7638 long_names for fully qualified output names; NOTE: ML programs
  7639 (special tactics, packages etc.) referring to internal names may have
  7640 to be adapted to cope with fully qualified names; in case of severe
  7641 backward campatibility problems try setting 'global_names' at compile
  7642 time to have enrything declared within a flat name space; one may also
  7643 fine tune name declarations in theories via the 'global' and 'local'
  7644 section;
  7645 
  7646 * reimplemented the implicit simpset and claset using the new anytype
  7647 data filed in signatures; references simpset:simpset ref etc. are
  7648 replaced by functions simpset:unit->simpset and
  7649 simpset_ref:unit->simpset ref; COMPATIBILITY: use isatool fixclasimp
  7650 to patch your ML files accordingly;
  7651 
  7652 * HTML output now includes theory graph data for display with Java
  7653 applet or isatool browser; data generated automatically via isatool
  7654 usedir (see -i option, ISABELLE_USEDIR_OPTIONS);
  7655 
  7656 * defs may now be conditional; improved rewrite_goals_tac to handle
  7657 conditional equations;
  7658 
  7659 * defs now admits additional type arguments, using TYPE('a) syntax;
  7660 
  7661 * theory aliases via merge (e.g. M=A+B+C) no longer supported, always
  7662 creates a new theory node; implicit merge of thms' signatures is
  7663 restricted to 'trivial' ones; COMPATIBILITY: one may have to use
  7664 transfer:theory->thm->thm in (rare) cases;
  7665 
  7666 * improved handling of draft signatures / theories; draft thms (and
  7667 ctyps, cterms) are automatically promoted to real ones;
  7668 
  7669 * slightly changed interfaces for oracles: admit many per theory, named
  7670 (e.g. oracle foo = mlfun), additional name argument for invoke_oracle;
  7671 
  7672 * print_goals: optional output of const types (set show_consts and
  7673 show_types);
  7674 
  7675 * improved output of warnings (###) and errors (***);
  7676 
  7677 * subgoal_tac displays a warning if the new subgoal has type variables;
  7678 
  7679 * removed old README and Makefiles;
  7680 
  7681 * replaced print_goals_ref hook by print_current_goals_fn and result_error_fn;
  7682 
  7683 * removed obsolete init_pps and init_database;
  7684 
  7685 * deleted the obsolete tactical STATE, which was declared by
  7686     fun STATE tacfun st = tacfun st st;
  7687 
  7688 * cd and use now support path variables, e.g. $ISABELLE_HOME, or ~
  7689 (which abbreviates $HOME);
  7690 
  7691 * changed Pure/Sequence interface (see Pure/seq.ML); COMPATIBILITY:
  7692 use isatool fixseq to adapt your ML programs (this works for fully
  7693 qualified references to the Sequence structure only!);
  7694 
  7695 * use_thy no longer requires writable current directory; it always
  7696 reloads .ML *and* .thy file, if either one is out of date;
  7697 
  7698 
  7699 *** Classical Reasoner ***
  7700 
  7701 * Clarify_tac, clarify_tac, clarify_step_tac, Clarify_step_tac: new
  7702 tactics that use classical reasoning to simplify a subgoal without
  7703 splitting it into several subgoals;
  7704 
  7705 * Safe_tac: like safe_tac but uses the default claset;
  7706 
  7707 
  7708 *** Simplifier ***
  7709 
  7710 * added simplification meta rules:
  7711     (asm_)(full_)simplify: simpset -> thm -> thm;
  7712 
  7713 * simplifier.ML no longer part of Pure -- has to be loaded by object
  7714 logics (again);
  7715 
  7716 * added prems argument to simplification procedures;
  7717 
  7718 * HOL, FOL, ZF: added infix function `addsplits':
  7719   instead of `<simpset> setloop (split_tac <thms>)'
  7720   you can simply write `<simpset> addsplits <thms>'
  7721 
  7722 
  7723 *** Syntax ***
  7724 
  7725 * TYPE('a) syntax for type reflection terms;
  7726 
  7727 * no longer handles consts with name "" -- declare as 'syntax' instead;
  7728 
  7729 * pretty printer: changed order of mixfix annotation preference (again!);
  7730 
  7731 * Pure: fixed idt/idts vs. pttrn/pttrns syntactic categories;
  7732 
  7733 
  7734 *** HOL ***
  7735 
  7736 * HOL: there is a new splitter `split_asm_tac' that can be used e.g.
  7737   with `addloop' of the simplifier to faciliate case splitting in premises.
  7738 
  7739 * HOL/TLA: Stephan Merz's formalization of Lamport's Temporal Logic of Actions;
  7740 
  7741 * HOL/Auth: new protocol proofs including some for the Internet
  7742   protocol TLS;
  7743 
  7744 * HOL/Map: new theory of `maps' a la VDM;
  7745 
  7746 * HOL/simplifier: simplification procedures nat_cancel_sums for
  7747 cancelling out common nat summands from =, <, <= (in)equalities, or
  7748 differences; simplification procedures nat_cancel_factor for
  7749 cancelling common factor from =, <, <= (in)equalities over natural
  7750 sums; nat_cancel contains both kinds of procedures, it is installed by
  7751 default in Arith.thy -- this COULD MAKE EXISTING PROOFS FAIL;
  7752 
  7753 * HOL/simplifier: terms of the form
  7754   `? x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x)'  (or t=x)
  7755   are rewritten to
  7756   `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t)',
  7757   and those of the form
  7758   `! x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x) --> R(x)'  (or t=x)
  7759   are rewritten to
  7760   `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t) --> R(t)',
  7761 
  7762 * HOL/datatype
  7763   Each datatype `t' now comes with a theorem `split_t_case' of the form
  7764 
  7765   P(t_case f1 ... fn x) =
  7766      ( (!y1 ... ym1. x = C1 y1 ... ym1 --> P(f1 y1 ... ym1)) &
  7767         ...
  7768        (!y1 ... ymn. x = Cn y1 ... ymn --> P(f1 y1 ... ymn))
  7769      )
  7770 
  7771   and a theorem `split_t_case_asm' of the form
  7772 
  7773   P(t_case f1 ... fn x) =
  7774     ~( (? y1 ... ym1. x = C1 y1 ... ym1 & ~P(f1 y1 ... ym1)) |
  7775         ...
  7776        (? y1 ... ymn. x = Cn y1 ... ymn & ~P(f1 y1 ... ymn))
  7777      )
  7778   which can be added to a simpset via `addsplits'. The existing theorems
  7779   expand_list_case and expand_option_case have been renamed to
  7780   split_list_case and split_option_case.
  7781 
  7782 * HOL/Arithmetic:
  7783   - `pred n' is automatically converted to `n-1'.
  7784     Users are strongly encouraged not to use `pred' any longer,
  7785     because it will disappear altogether at some point.
  7786   - Users are strongly encouraged to write "0 < n" rather than
  7787     "n ~= 0". Theorems and proof tools have been modified towards this
  7788     `standard'.
  7789 
  7790 * HOL/Lists:
  7791   the function "set_of_list" has been renamed "set" (and its theorems too);
  7792   the function "nth" now takes its arguments in the reverse order and
  7793   has acquired the infix notation "!" as in "xs!n".
  7794 
  7795 * HOL/Set: UNIV is now a constant and is no longer translated to Compl{};
  7796 
  7797 * HOL/Set: The operator (UN x.B x) now abbreviates (UN x:UNIV. B x) and its
  7798   specialist theorems (like UN1_I) are gone.  Similarly for (INT x.B x);
  7799 
  7800 * HOL/record: extensible records with schematic structural subtyping
  7801 (single inheritance); EXPERIMENTAL version demonstrating the encoding,
  7802 still lacks various theorems and concrete record syntax;
  7803 
  7804 
  7805 *** HOLCF ***
  7806 
  7807 * removed "axioms" and "generated by" sections;
  7808 
  7809 * replaced "ops" section by extended "consts" section, which is capable of
  7810   handling the continuous function space "->" directly;
  7811 
  7812 * domain package:
  7813   . proves theorems immediately and stores them in the theory,
  7814   . creates hierachical name space,
  7815   . now uses normal mixfix annotations (instead of cinfix...),
  7816   . minor changes to some names and values (for consistency),
  7817   . e.g. cases -> casedist, dists_eq -> dist_eqs, [take_lemma] -> take_lemmas,
  7818   . separator between mutual domain defs: changed "," to "and",
  7819   . improved handling of sort constraints;  now they have to
  7820     appear on the left-hand side of the equations only;
  7821 
  7822 * fixed LAM <x,y,zs>.b syntax;
  7823 
  7824 * added extended adm_tac to simplifier in HOLCF -- can now discharge
  7825 adm (%x. P (t x)), where P is chainfinite and t continuous;
  7826 
  7827 
  7828 *** FOL and ZF ***
  7829 
  7830 * FOL: there is a new splitter `split_asm_tac' that can be used e.g.
  7831   with `addloop' of the simplifier to faciliate case splitting in premises.
  7832 
  7833 * qed_spec_mp, qed_goal_spec_mp, qed_goalw_spec_mp are available, as
  7834 in HOL, they strip ALL and --> from proved theorems;
  7835 
  7836 
  7837 
  7838 New in Isabelle94-8 (May 1997)
  7839 ------------------------------
  7840 
  7841 *** General Changes ***
  7842 
  7843 * new utilities to build / run / maintain Isabelle etc. (in parts
  7844 still somewhat experimental); old Makefiles etc. still functional;
  7845 
  7846 * new 'Isabelle System Manual';
  7847 
  7848 * INSTALL text, together with ./configure and ./build scripts;
  7849 
  7850 * reimplemented type inference for greater efficiency, better error
  7851 messages and clean internal interface;
  7852 
  7853 * prlim command for dealing with lots of subgoals (an easier way of
  7854 setting goals_limit);
  7855 
  7856 
  7857 *** Syntax ***
  7858 
  7859 * supports alternative (named) syntax tables (parser and pretty
  7860 printer); internal interface is provided by add_modesyntax(_i);
  7861 
  7862 * Pure, FOL, ZF, HOL, HOLCF now support symbolic input and output; to
  7863 be used in conjunction with the Isabelle symbol font; uses the
  7864 "symbols" syntax table;
  7865 
  7866 * added token_translation interface (may translate name tokens in
  7867 arbitrary ways, dependent on their type (free, bound, tfree, ...) and
  7868 the current print_mode); IMPORTANT: user print translation functions
  7869 are responsible for marking newly introduced bounds
  7870 (Syntax.mark_boundT);
  7871 
  7872 * token translations for modes "xterm" and "xterm_color" that display
  7873 names in bold, underline etc. or colors (which requires a color
  7874 version of xterm);
  7875 
  7876 * infixes may now be declared with names independent of their syntax;
  7877 
  7878 * added typed_print_translation (like print_translation, but may
  7879 access type of constant);
  7880 
  7881 
  7882 *** Classical Reasoner ***
  7883 
  7884 Blast_tac: a new tactic!  It is often more powerful than fast_tac, but has
  7885 some limitations.  Blast_tac...
  7886   + ignores addss, addbefore, addafter; this restriction is intrinsic
  7887   + ignores elimination rules that don't have the correct format
  7888         (the conclusion MUST be a formula variable)
  7889   + ignores types, which can make HOL proofs fail
  7890   + rules must not require higher-order unification, e.g. apply_type in ZF
  7891     [message "Function Var's argument not a bound variable" relates to this]
  7892   + its proof strategy is more general but can actually be slower
  7893 
  7894 * substitution with equality assumptions no longer permutes other
  7895 assumptions;
  7896 
  7897 * minor changes in semantics of addafter (now called addaltern); renamed
  7898 setwrapper to setWrapper and compwrapper to compWrapper; added safe wrapper
  7899 (and access functions for it);
  7900 
  7901 * improved combination of classical reasoner and simplifier:
  7902   + functions for handling clasimpsets
  7903   + improvement of addss: now the simplifier is called _after_ the
  7904     safe steps.
  7905   + safe variant of addss called addSss: uses safe simplifications
  7906     _during_ the safe steps. It is more complete as it allows multiple
  7907     instantiations of unknowns (e.g. with slow_tac).
  7908 
  7909 *** Simplifier ***
  7910 
  7911 * added interface for simplification procedures (functions that
  7912 produce *proven* rewrite rules on the fly, depending on current
  7913 redex);
  7914 
  7915 * ordering on terms as parameter (used for ordered rewriting);
  7916 
  7917 * new functions delcongs, deleqcongs, and Delcongs. richer rep_ss;
  7918 
  7919 * the solver is now split into a safe and an unsafe part.
  7920 This should be invisible for the normal user, except that the
  7921 functions setsolver and addsolver have been renamed to setSolver and
  7922 addSolver; added safe_asm_full_simp_tac;
  7923 
  7924 
  7925 *** HOL ***
  7926 
  7927 * a generic induction tactic `induct_tac' which works for all datatypes and
  7928 also for type `nat';
  7929 
  7930 * a generic case distinction tactic `exhaust_tac' which works for all
  7931 datatypes and also for type `nat';
  7932 
  7933 * each datatype comes with a function `size';
  7934 
  7935 * patterns in case expressions allow tuple patterns as arguments to
  7936 constructors, for example `case x of [] => ... | (x,y,z)#ps => ...';
  7937 
  7938 * primrec now also works with type nat;
  7939 
  7940 * recdef: a new declaration form, allows general recursive functions to be
  7941 defined in theory files.  See HOL/ex/Fib, HOL/ex/Primes, HOL/Subst/Unify.
  7942 
  7943 * the constant for negation has been renamed from "not" to "Not" to
  7944 harmonize with FOL, ZF, LK, etc.;
  7945 
  7946 * HOL/ex/LFilter theory of a corecursive "filter" functional for
  7947 infinite lists;
  7948 
  7949 * HOL/Modelcheck demonstrates invocation of model checker oracle;
  7950 
  7951 * HOL/ex/Ring.thy declares cring_simp, which solves equational
  7952 problems in commutative rings, using axiomatic type classes for + and *;
  7953 
  7954 * more examples in HOL/MiniML and HOL/Auth;
  7955 
  7956 * more default rewrite rules for quantifiers, union/intersection;
  7957 
  7958 * a new constant `arbitrary == @x.False';
  7959 
  7960 * HOLCF/IOA replaces old HOL/IOA;
  7961 
  7962 * HOLCF changes: derived all rules and arities
  7963   + axiomatic type classes instead of classes
  7964   + typedef instead of faking type definitions
  7965   + eliminated the internal constants less_fun, less_cfun, UU_fun, UU_cfun etc.
  7966   + new axclasses cpo, chfin, flat with flat < chfin < pcpo < cpo < po
  7967   + eliminated the types void, one, tr
  7968   + use unit lift and bool lift (with translations) instead of one and tr
  7969   + eliminated blift from Lift3.thy (use Def instead of blift)
  7970   all eliminated rules are derived as theorems --> no visible changes ;
  7971 
  7972 
  7973 *** ZF ***
  7974 
  7975 * ZF now has Fast_tac, Simp_tac and Auto_tac.  Union_iff is a now a default
  7976 rewrite rule; this may affect some proofs.  eq_cs is gone but can be put back
  7977 as ZF_cs addSIs [equalityI];
  7978 
  7979 
  7980 
  7981 New in Isabelle94-7 (November 96)
  7982 ---------------------------------
  7983 
  7984 * allowing negative levels (as offsets) in prlev and choplev;
  7985 
  7986 * super-linear speedup for large simplifications;
  7987 
  7988 * FOL, ZF and HOL now use miniscoping: rewriting pushes
  7989 quantifications in as far as possible (COULD MAKE EXISTING PROOFS
  7990 FAIL); can suppress it using the command Delsimps (ex_simps @
  7991 all_simps); De Morgan laws are also now included, by default;
  7992 
  7993 * improved printing of ==>  :  ~:
  7994 
  7995 * new object-logic "Sequents" adds linear logic, while replacing LK
  7996 and Modal (thanks to Sara Kalvala);
  7997 
  7998 * HOL/Auth: correctness proofs for authentication protocols;
  7999 
  8000 * HOL: new auto_tac combines rewriting and classical reasoning (many
  8001 examples on HOL/Auth);
  8002 
  8003 * HOL: new command AddIffs for declaring theorems of the form P=Q to
  8004 the rewriter and classical reasoner simultaneously;
  8005 
  8006 * function uresult no longer returns theorems in "standard" format;
  8007 regain previous version by: val uresult = standard o uresult;
  8008 
  8009 
  8010 
  8011 New in Isabelle94-6
  8012 -------------------
  8013 
  8014 * oracles -- these establish an interface between Isabelle and trusted
  8015 external reasoners, which may deliver results as theorems;
  8016 
  8017 * proof objects (in particular record all uses of oracles);
  8018 
  8019 * Simp_tac, Fast_tac, etc. that refer to implicit simpset / claset;
  8020 
  8021 * "constdefs" section in theory files;
  8022 
  8023 * "primrec" section (HOL) no longer requires names;
  8024 
  8025 * internal type "tactic" now simply "thm -> thm Sequence.seq";
  8026 
  8027 
  8028 
  8029 New in Isabelle94-5
  8030 -------------------
  8031 
  8032 * reduced space requirements;
  8033 
  8034 * automatic HTML generation from theories;
  8035 
  8036 * theory files no longer require "..." (quotes) around most types;
  8037 
  8038 * new examples, including two proofs of the Church-Rosser theorem;
  8039 
  8040 * non-curried (1994) version of HOL is no longer distributed;
  8041 
  8042 
  8043 
  8044 New in Isabelle94-4
  8045 -------------------
  8046 
  8047 * greatly reduced space requirements;
  8048 
  8049 * theory files (.thy) no longer require \...\ escapes at line breaks;
  8050 
  8051 * searchable theorem database (see the section "Retrieving theorems" on
  8052 page 8 of the Reference Manual);
  8053 
  8054 * new examples, including Grabczewski's monumental case study of the
  8055 Axiom of Choice;
  8056 
  8057 * The previous version of HOL renamed to Old_HOL;
  8058 
  8059 * The new version of HOL (previously called CHOL) uses a curried syntax
  8060 for functions.  Application looks like f a b instead of f(a,b);
  8061 
  8062 * Mutually recursive inductive definitions finally work in HOL;
  8063 
  8064 * In ZF, pattern-matching on tuples is now available in all abstractions and
  8065 translates to the operator "split";
  8066 
  8067 
  8068 
  8069 New in Isabelle94-3
  8070 -------------------
  8071 
  8072 * new infix operator, addss, allowing the classical reasoner to
  8073 perform simplification at each step of its search.  Example:
  8074         fast_tac (cs addss ss)
  8075 
  8076 * a new logic, CHOL, the same as HOL, but with a curried syntax
  8077 for functions.  Application looks like f a b instead of f(a,b).  Also pairs
  8078 look like (a,b) instead of <a,b>;
  8079 
  8080 * PLEASE NOTE: CHOL will eventually replace HOL!
  8081 
  8082 * In CHOL, pattern-matching on tuples is now available in all abstractions.
  8083 It translates to the operator "split".  A new theory of integers is available;
  8084 
  8085 * In ZF, integer numerals now denote two's-complement binary integers.
  8086 Arithmetic operations can be performed by rewriting.  See ZF/ex/Bin.ML;
  8087 
  8088 * Many new examples: I/O automata, Church-Rosser theorem, equivalents
  8089 of the Axiom of Choice;
  8090 
  8091 
  8092 
  8093 New in Isabelle94-2
  8094 -------------------
  8095 
  8096 * Significantly faster resolution;
  8097 
  8098 * the different sections in a .thy file can now be mixed and repeated
  8099 freely;
  8100 
  8101 * Database of theorems for FOL, HOL and ZF.  New
  8102 commands including qed, qed_goal and bind_thm store theorems in the database.
  8103 
  8104 * Simple database queries: return a named theorem (get_thm) or all theorems of
  8105 a given theory (thms_of), or find out what theory a theorem was proved in
  8106 (theory_of_thm);
  8107 
  8108 * Bugs fixed in the inductive definition and datatype packages;
  8109 
  8110 * The classical reasoner provides deepen_tac and depth_tac, making FOL_dup_cs
  8111 and HOL_dup_cs obsolete;
  8112 
  8113 * Syntactic ambiguities caused by the new treatment of syntax in Isabelle94-1
  8114 have been removed;
  8115 
  8116 * Simpler definition of function space in ZF;
  8117 
  8118 * new results about cardinal and ordinal arithmetic in ZF;
  8119 
  8120 * 'subtype' facility in HOL for introducing new types as subsets of existing
  8121 types;
  8122 
  8123 :mode=text:wrap=hard:maxLineLen=72: